With the increasing integration of large-scale distributed energy resources into the grid,traditional distribution network optimization and dispatch methods struggle to address the challenges posed by both generation ...With the increasing integration of large-scale distributed energy resources into the grid,traditional distribution network optimization and dispatch methods struggle to address the challenges posed by both generation and load.Accounting for these issues,this paper proposes a multi-timescale coordinated optimization dispatch method for distribution networks.First,the probability box theory was employed to determine the uncertainty intervals of generation and load forecasts,based on which,the requirements for flexibility dispatch and capacity constraints of the grid were calculated and analyzed.Subsequently,a multi-timescale optimization framework was constructed,incorporating the generation and load forecast uncertainties.This framework included optimization models for dayahead scheduling,intra-day optimization,and real-time adjustments,aiming to meet flexibility needs across different timescales and improve the economic efficiency of the grid.Furthermore,an improved soft actor-critic algorithm was introduced to enhance the uncertainty exploration capability.Utilizing a centralized training and decentralized execution framework,a multi-agent SAC network model was developed to improve the decision-making efficiency of the agents.Finally,the effectiveness and superiority of the proposed method were validated using a modified IEEE-33 bus test system.展开更多
BACKGROUND Pepsinogen(PG)and the PG I/II ratio(PGR)are critical indicators for diagnosing Helicobacter pylori infection and chronic atrophic gastritis,and assessing gastric cancer risk.Existing reference intervals(RIs...BACKGROUND Pepsinogen(PG)and the PG I/II ratio(PGR)are critical indicators for diagnosing Helicobacter pylori infection and chronic atrophic gastritis,and assessing gastric cancer risk.Existing reference intervals(RIs)often overlook age,sex,and demographic variations.Partitioned RIs,while considering these factors,fail to capture the gradual age-related physiological changes.Next-generation RIs offer a solution to this limitation.AIM To investigate age-and sex-specific dynamics of PG and establish next-generation RIs for adults and the elderly in northern China.METHODS After screening,708 healthy individuals were included in this observational study.Serum PG was measured using chemiluminescence immunoassay.Age-and sex-related effects on PG were analyzed with a two-way analysis of variance.RI partitioning was determined by the standard deviation ratio(SDR).Traditional RIs were established using a non-parametric approach.Generalized Additive Models for Location,Scale,and Shape(GAMLSS)modeled age-related trends and continuous reference percentiles for PG I and PG II.Reference limit flagging rates for both RI types were compared.RESULTS PG I and PG II levels were influenced by age(P<0.001)and sex(P<0.001),while PGR remained stable.Age-specific RIs were required for PG I(SDR=0.366)and PG II(SDR=0.424).Partitioned RIs were established for PG I and PG II,with a single RI for PGR.GAMLSS modeling revealed distinct age-dependent trajectories:PG I increased from a median of 39.75μg/L at age 20 years to 49.75μg/L at age 60 years,a 25.16%increase,after which it plateaued through age 80 years.In contrast,PG II showed a continuous rise throughout the age range,with the median value increasing from 5.07μg/L at age 20 years to 8.36μg/L at age 80 years,corresponding to a 64.89%increase.Continuous reference percentiles intuitively reflected these trends and were detailed in this study.Next-generation RIs demonstrated superior accuracy compared to partitioned RIs when applied to specific age subgroups.CONCLUSION This study elucidates the age-and sex-specific dynamics of PG and,to our knowledge,is the first to establish next-generation RIs for PG,supporting more individualized interpretation in laboratory medicine.展开更多
Objectives:This study aimed to explore the perceptions and recommendations of multiparas and health-related professionals regarding appropriate birth intervals(Bis)and key determinants.Methods:In-depth semi-structured...Objectives:This study aimed to explore the perceptions and recommendations of multiparas and health-related professionals regarding appropriate birth intervals(Bis)and key determinants.Methods:In-depth semi-structured interviews were conducted between April 1 and June 30,2022.Nine multiparas and thirteen health-related professionals were purposefully sampled until data saturation was reached.A thematic analysis approach was applied to the interview transcripts,utilizing dual independent coding and consensus validation in NVivo 12.0.Results:The data generated two overarching categories:1)balanced decision-making on the appropriate birth intervals and 2)internal and external determinants integrated with health and societal considerations.Four key themes emerged following the two categories:1)consistency and discrepancy between the actual and recommended birth intervals of multiparas;2)health-and developmentoriented professional recommendations;3)internal determinants related to individual-level factors;and 4)external determinants related to child-related factors,family support,and social security.Weighing women's reproductive health and career development,multiparas and health-related professionals perceived a length between 18 and 36 months as the appropriate Bl.Conclusion:Multiparas and health-related professionals shaped their balanced recommendations on a relatively appropriate birth interval ranging from 18 to 36 months,which was influenced by women's individual-level factors,child-related factors,family support,and social security.Targeted social and healthcare services should be offered to women and their families during the Bls.展开更多
Objective:To evaluate the effectiveness of DTwP-HB-Hib vaccination dosing intervals at eight weeks versus four weeks on the immunogenicity of the diphtheria component.Methods:This is a randomized,open-label,parallel,c...Objective:To evaluate the effectiveness of DTwP-HB-Hib vaccination dosing intervals at eight weeks versus four weeks on the immunogenicity of the diphtheria component.Methods:This is a randomized,open-label,parallel,controlled trial on healthy two-month-old infants who had not received DTwP-HB-Hib vaccinations.The infants received three doses of the vaccine either at an eight-week or four-week interval.The anti-diphtheria toxoid IgG antibody levels before and after three doses of the vaccination were measured using ELISA.Results:Eighty infants were enrolled in this study,with 64 fulfilling the study requirements and randomized into two groups.All study participants exhibited uncertain protection against diphtheria antibodies(0.01-0.99 IU/mL)at the beginning of the study with an average of(0.023±0.009)IU/mL and(0.026±0.009)IU/mL in eight weeks and four weeks groups.Following three doses of the vaccination,the antibody level rose to an average of(1.320±0.234)IU/mL in the eight-week group and(1.307±0.186)IU/mL in the four-week group,with no statistically significant difference in the antibody levels observed(P=0.814).Conclusions:DTwP-HB-Hib vaccinations can be administered at an eight-week or four-week interval,as they do not significantly affect the level of anti-diphtheria IgG antibodies.展开更多
BACKGROUND The reference ranges for biochemical parameters can fluctuate due to factors like altitude,age,gender,and socioeconomic conditions.These values are crucial for interpreting laboratory data and guide clinica...BACKGROUND The reference ranges for biochemical parameters can fluctuate due to factors like altitude,age,gender,and socioeconomic conditions.These values are crucial for interpreting laboratory data and guide clinical treatment decisions.Currently,there is no established set of reference intervals for cord blood biochemical parameters of newborns in India,particularly in Mumbai.AIM To create cord blood biochemical parameters reference intervals specifically for Mumbai,India.METHODS A cross-sectional study was conducted in an Indian tertiary care hospital.This study focused on healthy newborns with normal birth weight,born to pregnant mothers without health issues.Cord blood samples,approximately 2-3 mL in volume,were collected from 210 term neonates.These samples were divided into fluoride(glucose)and clot activator(serum)tubes and were subsequently analyzed in the institute's biochemical laboratory.The data obtained from the analysis was then subjected to statistical analysis.The result of the Shapiro-Wilk test suggested non-normality in the data distribution.Consequently,nonparametric statistics were utilized for analysis.The Mann-Whitney U test was utilized to compare parameter distributions among different factors,including the infant’s sex,delivery method,maternal age,and obstetric history.A significance level of P<0.05 was considered to indicate statistical significance.RESULTS The following represent the median figures and central 95 percentile reference intervals for biochemical parameters in umbilical cord blood of newborns:Serum direct bilirubin=(0.1-0.55)mg/dL,indirect bilirubin=(0.64-2.26)mg/dL,total bilirubin=(0.62-3.14)mg/dL,creatinine=(0.27-0.76)mg/dL,sodium=(128.19-143.26)mmol/L,chloride=(100.19-111.68)mmol/L,potassium=(1.62-9.98)mmol/L and plasma glucose=(24.75-94.23)mg/dL.Statistically significant differences were observed in serum sodium,potassium,and plasma glucose levels when comparing delivery modes.CONCLUSION This is the pioneering study in which first time,the biochemical reference intervals in cord blood for newborns are established in western India.The values are applicable for newborns from this area.Larger study throughout the country is required.展开更多
Most reliability studies assume large samples or independence among components,but these assump-tions often fail in practice,leading to imprecise inference.We address this issue by constructing confidence intervals(CI...Most reliability studies assume large samples or independence among components,but these assump-tions often fail in practice,leading to imprecise inference.We address this issue by constructing confidence intervals(CIs)for the reliability of two-component systems with Weibull distributed failure times under a copula-frailty framework.Our construction integrates gamma-distributed frailties to capture unobserved heterogeneity and a copula-based dependence structure for correlated failures.The main contribution of this work is to derive adjusted CIs that explicitly incorporate the copula parameter in the variance-covariance matrix,achieving near-nominal coverage probabilities even in small samples or highly dependent settings.Through simulation studies,we show that,although traditional methods may suffice with moderate dependence and large samples,the proposed CIs offer notable benefits when dependence is strong or data are sparse.We further illustrate our construction with a synthetic example illustrating how penalized estimation can mitigate the issue of a degenerate Hessian matrix under high dependence and limited observations,so enabling uncertainty quantification despite deviations from nominal assumptions.Overall,our results fill a gap in reliability modeling for systems prone to correlated failures,and contribute to more robust inference in engineering,industrial,and biomedical applications.展开更多
Purpose–The deformation of the roadbed is easily influenced by the external environment to improve the accuracy of high-speed railway subgrade settlement prediction.Design/methodology/approach–A high-speed railway s...Purpose–The deformation of the roadbed is easily influenced by the external environment to improve the accuracy of high-speed railway subgrade settlement prediction.Design/methodology/approach–A high-speed railway subgrade settlement interval prediction method using the secretary bird optimization(SBOA)algorithm to optimize the BP neural network under the premise of gray relational analysis is proposed.Findings–Using the SBOA algorithm to optimize the BP neural network,the optimal weights and thresholds are obtained,and the best parameter prediction model is combined.The data were collected from the sensors deployed through the subgrade settlement monitoring system,and the gray relational analysis is used to verify that all four influencing factors had a great correlation to the subgrade settlement,and the collected data are verified using the model.Originality/value–The experimental results show that the SBOA-BP model has higher prediction accuracy than the BP model,and the SBOA-BP model has a wider range of prediction intervals for a given confidence level,which can provide higher guiding value for practical engineering applications.展开更多
The distillation process is an important chemical process,and the application of data-driven modelling approach has the potential to reduce model complexity compared to mechanistic modelling,thus improving the efficie...The distillation process is an important chemical process,and the application of data-driven modelling approach has the potential to reduce model complexity compared to mechanistic modelling,thus improving the efficiency of process optimization or monitoring studies.However,the distillation process is highly nonlinear and has multiple uncertainty perturbation intervals,which brings challenges to accurate data-driven modelling of distillation processes.This paper proposes a systematic data-driven modelling framework to solve these problems.Firstly,data segment variance was introduced into the K-means algorithm to form K-means data interval(KMDI)clustering in order to cluster the data into perturbed and steady state intervals for steady-state data extraction.Secondly,maximal information coefficient(MIC)was employed to calculate the nonlinear correlation between variables for removing redundant features.Finally,extreme gradient boosting(XGBoost)was integrated as the basic learner into adaptive boosting(AdaBoost)with the error threshold(ET)set to improve weights update strategy to construct the new integrated learning algorithm,XGBoost-AdaBoost-ET.The superiority of the proposed framework is verified by applying this data-driven modelling framework to a real industrial process of propylene distillation.展开更多
Background Vibrotactile feedback systems are widely used in assistive technology,wearable devices,and virtual environments to deliver precise tactile information.The timing of interstimulus intervals(ISIs)plays a crit...Background Vibrotactile feedback systems are widely used in assistive technology,wearable devices,and virtual environments to deliver precise tactile information.The timing of interstimulus intervals(ISIs)plays a critical role in determining how accurately users perceive and interpret vibrotactile patterns.The optimal use of ISIs can increase the effectiveness of these systems,improve user interaction,and enable reliable,intuitive feedback in diverse applications.We examined how different interstimulus intervals ISIs impact the accuracy of vibrotactile pattern recognition.Methods Participants wore a forearm-mounted device with six voice coil actuators arranged in a 3×2 grid,delivering Braille-based vibrotactile patterns sequentially at ISIs ranging from 10 to 2500 ms.Eight participants performed identification tasks involving Icelandic Braille patterns categorized as either short(2-3 actuators)or long(4-5 actuators).A repeated measures ANOVA was conducted to assess the effects of ISI,pattern type,and practice(across two testing blocks)on pattern recognition accuracy.Results For short patterns,accuracy was highest(92%-98%)at ISIs of 50-700 ms,with peak performance at 300 ms.For long patterns,accuracy reached 86%-94%at ISIs of 100-500 ms,peaking at 400 ms.Participants were more accurate with short patterns,and performance improved significantly over time for both short and long patterns,highlighting the importance of training for vibrotactile pattern recognition.Conclusions These results underscore the importance of careful selection of ISIs in vibrotactile feedback systems for accurate pattern identification.The findings provide valuable insights for conveying tactile information using wearable devices,contributing to better tactile feedback and performance in applications requiring precise vibrotactile information delivery.展开更多
Preterm birth and suboptimal fetal growth remain significant perinatal challenges worldwide.Recent data indicate that China's perinatal profile has improved due to reductions in preterm birth rates.However,the cou...Preterm birth and suboptimal fetal growth remain significant perinatal challenges worldwide.Recent data indicate that China's perinatal profile has improved due to reductions in preterm birth rates.However,the country has a 6.5%prevalence of small-for-gestational-age(SGA),ranking fifth globally in total SGA birth numbers^([1,2]).展开更多
Objective： To evaluate the changes in Tp-e interval （an interval from the peak to the end of the T wave）, QT interval and Tp-e/QT ratio of the body surface ECG in patients with left ventricular hypertrophy （LVH）....Objective： To evaluate the changes in Tp-e interval （an interval from the peak to the end of the T wave）, QT interval and Tp-e/QT ratio of the body surface ECG in patients with left ventricular hypertrophy （LVH）. Methods： The Tp-e interval and QT interval were measured on body surface ECGs in 42 patients without either hypertension or LVH （control group）, 41 patients having hypertension but not LVH （non-LVH group）, and 38 patients with both hypertension and LVH （LVH group）. Results： The mean corrected QT （QTc） interval, and mean corrected Tp-e[T（p-e）c] interval were significantly longer in the LVH group （0.430±0.021s vs. 0.409±0.019s, p 〈 0.01; 0.098±0.013s vs. 0.088±0.011s, respectively） than those in the control group. The Tp-e/QT ratio was also amplified in LVH group （0.232± 0.028 vs.0.218± 0.027） （p 〈 0.05）. Conclusion： LVH increased the QT interval, Tp-e interval and Tp-e/QT ratio of the body surface ECG.展开更多
In the theory of belief functions, the measure of uncertainty is an important concept, which is used for representing some types of uncertainty incorporated in bodies of evidence such as the discord and the non-specif...In the theory of belief functions, the measure of uncertainty is an important concept, which is used for representing some types of uncertainty incorporated in bodies of evidence such as the discord and the non-specificity. For the non-specificity part, some traditional measures use for reference the Hartley measure in classical set theory; other traditional measures use the simple and heuristic function for joint use of mass assignments and the cardinality of focal elements. In this paper, a new non-specificity measure is proposed using lengths of belief intervals, which represent the degree of imprecision. Therefore, it has more intuitive physical meaning. It can be proved that our new measure can be rewritten in a general form for the non-specificity. Our new measure is also proved to be a strict non-specificity measure with some desired properties. Numerical examples, simulations, the related analyses and proofs are provided to show the characteristics and good properties of the new non-specificity definition. An example of an application of the new non- specificity measure is also presented.展开更多
Since the great 1303 Hongtong, Shanxi, earthquake of magnitude 8, 700 years have elapsed. To analyze the long-term seismic potential, this paper divides the Taiyuan-Linfen portion of the Shanxi graben system into 5 se...Since the great 1303 Hongtong, Shanxi, earthquake of magnitude 8, 700 years have elapsed. To analyze the long-term seismic potential, this paper divides the Taiyuan-Linfen portion of the Shanxi graben system into 5 seismogenic segments. Based on data of historical earthquakes and GPS observation, the authors estimate mean seismic-moment rates and average recurrence intervals of strong earthquakes for the individual segments, and fur-ther analyze relative levels of current stress cumulation on the segments based on mapping b-values along the gra-ben system by using the network seismic data for the recent over 30 years. The main result shows that the Linfen basin segment has an estimated mean seismic-moment rate of 2.211016 Nm/a to 3.031016 Nm/a, and its average recurrence interval for M=7.5 earthquake is estimated to be between 1 560 and 2 140 years. For the Ling-shi-Hongtong segment, the estimated average recurrence interval for M=8 earthquakes is between 4 300 and 5 100 years, equivalent to having a mean moment-rate of 2.581016 Nm/a to 3.101016 Nm/a. The contour map of b-values shows that the two segments of Lingshi-Hongtong and Linfen basin have been being at low or relatively low stress levels, reflecting that since the 1303 M=8 and the 1695 M=7.5 earthquake ruptures, the fault-planes strengths of the both segments have not been resumed yet. And the other two segments, the Houma and the Jiexiu-Fenyang, have relatively high stress levels, and have been already identified as potential risky segments for the coming earthquakes from the analysis combining with the estimated average recurrence intervals of earth-quakes on the both segments.展开更多
Objectives To assess the impacts of public health interventions on the outbreak of SARS in Beijing by analyzing the intervals between symptom onset, hospital admission and notification of its cases. Methods Data of SA...Objectives To assess the impacts of public health interventions on the outbreak of SARS in Beijing by analyzing the intervals between symptom onset, hospital admission and notification of its cases. Methods Data of SARS cases reported from the Beijing Municipal Centers for Disease Prevention and Control (BCDC) were collected and analyzed by descriptive epidemiology. Results In the early epidemic period, the intervals between the disease onset and the hospital admission seemed irregular, so was the intervals between the hospital admission and the notification. After the middle ten days of April, the intervals turned out to be more regular, and the disordered situation in terms of the hospital admission and the case notification was gradually brought under control. Conclusions Public health interventions against SARS has revealed positive impacts on SARS control program in Beijing. The timing and sensitivity of epidemic information reporting systems has been greatly improved in Beijing as a result of successful fight against this disease.展开更多
Methodologies have been developed for calculating cutoffs of reservoir intervals with production capacity （RIPC） and reservoir intervals with accumulation capacity （RIAC） according to the types of pore throat stru...Methodologies have been developed for calculating cutoffs of reservoir intervals with production capacity （RIPC） and reservoir intervals with accumulation capacity （RIAC） according to the types of pore throat structures and dynamic force by using data from petrophysical analysis, production tests and mercury injection. The data are from clastic reservoirs in the third member （Es3） and the fourth member （Es4） of the Shahejie Formation in the Shengtuo area on the North Slope of the Dongying Sag, Jiyang Depression, China. The method of calculating cutoffs of RIPC is summarized as follows： 1） determination of permeability cutoffs of RIPC; 2） classification of types of pore-throat structures according to mercury injection data and then relating porosity to permeability and determining the relationship between porosity and permeability according to each type of pore-throat structure; and 3） calculating porosity cutoffs of RIPC using established correlation between porosity and permeability according to the type of pore throat structure. The method of calculating cutoffs of RIAC includes： 1） establishing a functional relationship between oil-water interracial tension and formation temperature; 2） calculating limiting values of maximum connected pore-throat radii according to formation temperature and dynamic forces of each reservoir interval; 3） correlating permeability with maximum connected pore-throat radius and then obtaining permeability cutoffs of RIAC; and 4） calculating porosity cutoffs on the basis of permeability cutoffs according to specific correlations, suitable for the type of porethroat structure. The results of this study show that porosity and permeability cutoffs of clastic reservoirs decrease with depth. For a fixed permeability cutoff, the porosity cutoff of R1PC varies because the type of pore throat is different. At a fixed temperature, porosity and permeability cutoffs of RIAC decrease as dynamic force increases. For a fixed permeability cutoff of effective hydrocarbon accumulation, the porosity cutoff also varies with different types of pore throat.展开更多
Based on the steady-state seepage method, we used the Mechanical Testing and Simulation 815.02 System and a self-designed seepage instrument for over-broken stone to measure seepage properties of water flows in three ...Based on the steady-state seepage method, we used the Mechanical Testing and Simulation 815.02 System and a self-designed seepage instrument for over-broken stone to measure seepage properties of water flows in three types of crushed rock samples. Three methods of confidence interval in describing permeability coefficients are presented: the secure interval, the calculated interval and the systemic interval. The lower bound of the secure interval can be applied to water-inrush and the upper bound can solve the problem of connectivity. For the calculated interval, as the axial pressure increases, the length of confidence interval is shortened and the upper and lower bounds are reduced. For the systemic interval, the length of its confidence interval, as well as the upper and lower bounds, clearly vary under low axial pressure but are fairly similar under high axial pressure. These three methods provide useful information and references for analyzing the permeability coefficient of over-broken rock.展开更多
A novel adaptive sampling interval algorithm for multitarget tracking is presented. This algorithm which is based on interacting multiple models incorporates the grey relational grade （GRG） into the particle swarm o...A novel adaptive sampling interval algorithm for multitarget tracking is presented. This algorithm which is based on interacting multiple models incorporates the grey relational grade （GRG） into the particle swarm optimization （PSO）. Firstly, the desired tracking accuracy is set for each target. Secondly, sampling intervals are selected as particles, and then the advantage of the GRG is taken as the measurement function for resource management. Meanwhile, the fitness value of the PSO is used to measure the difference between desired tracking accuracy and estimated tracking accuracy. Finally, it is suggested that the radar should track the target whose prediction value of the next sampling interval is the smallest. Simulations show that the proposed method improves both the tracking accuracy and tracking efficiency of the phased-array radar.展开更多
Objectives:To assess whether the extension of the flushing interval will increase risks of complications associated with totally implantable venous access port(TIVAP)in the off-treatment period.Methods:A retrospective...Objectives:To assess whether the extension of the flushing interval will increase risks of complications associated with totally implantable venous access port(TIVAP)in the off-treatment period.Methods:A retrospective single-center observational study was performed.Patients with a TIVAP in the off-treatment period that underwent regular flushing in our clinic were included.Data concerning patients and their TIVAPs were recorded.Patient baseline characteristics and TIVAP-related complications were analyzed.Continuous variables were analyzed by ANOVA or the Kruskal-Wallis H test.To compare the occurrence of TIVAP-related complications,the chi-square test was used;if needed,Fisher’s exact test was used.Results:Totally 607 patients were reviewed,and 563 patients were finally included.Thirteen complications were recorded,including 11 cases of catheter occlusion(1.95%),one case of port cannula rotation(0.18%),and one case of catheter tip malposition(0.18%).No device-related infection or venous thrombosis was recorded.Among these patients,the average flushing interval was 35.27±13.09 days.Patients were divided into three groups according to the flushing interval:every 28 days or less(Group 1,n=133);every 29-44 days(Group 2,n=350);and every 45 days or more(Group 3,n=80).No significant difference in catheter-related complications was found among the three groups(P>0.05).Conclusions:In the TIVAP off-treatment period,patients without any history of TIVAP-related complications during approximately one year can attempt to prolong the flushing interval to more than 4 weeks;we further suggest that 5-6 weeks may be an appropriate option for these patients.展开更多
The non-stationary behavior, caused by the train rmverrent, is the rmin factor for the variation of high speed railway channel. To measure the tirce-variant effect, the parameter of stationarity interval, in which the...The non-stationary behavior, caused by the train rmverrent, is the rmin factor for the variation of high speed railway channel. To measure the tirce-variant effect, the parameter of stationarity interval, in which the channel keeps constant or has no great change, is adopted based on Zhengzfiou- Xi＇an （Zhengxi） passenger dedicated line measurement with different train speeds. The stationarity interval is calculated through the definition of Local Region of Stationarity （LRS） under three train ve- locities. Furthermore, the time non-stationary characteristic of high speed pared with five standard railway channel is corn- Multiple-Input MultipleOutput （MIMO） channel models, i.e. Spatial Channel Model （SCM）, extended version of SCM （SCME）, Wireless World Initiative New Radio Phase II （WINNERII）, International Mobile Teleconmnications-Advanced （IMT-Advanced） and WiMAX models which contain the high speed moving scenario. The stationarity interval of real channel is 9 ms in 80% of the cases, which is shorter than those of the standard models. Hence the real channel of high speed railway changes more rapidly. The stationarity intervals of standard models are different due to different modeling methods and scenario def- initions. And the compared results are instructive for wireless system design in high speed railway.展开更多
Background： Hematologic and biochemical reference intervals depend on many factors, including age. A review of the literature highlights the lack of reference intervals for 6-wk-old specific pathogen free （SPF） Ham...Background： Hematologic and biochemical reference intervals depend on many factors, including age. A review of the literature highlights the lack of reference intervals for 6-wk-old specific pathogen free （SPF） Hampshire-Yorkshire crossbred pigs. For translational research, 6-wk-old pigs represent an important animal model for both human juvenile colitis and diabetes mellitus type 2 given the similarities between the porcine and human gastrointestinal maturation process. The aim of this study was to determine reference intervals for hematological and biochemical parameters in healthy 6-wk-old crossbred pigs. Blood samples were collected from 66 clinically healthy Hampshire-Yorkshire pigs. The pigs were 6 wks old, represented both sexes, and were housed in a SPF facility. Automated hematological and biochemical analysis were performed using an ADVIA 120 Hematology System and a Cobas 6000 C501 Clinical Chemistry Analyzer. Results： Reference intervals were calculated using both parametric and nonparametric methods. The mean, median, minimum, and maximum values were calculated. Conclusion： As pigs are used more frequently as medical models of human disease, having reference intervals for commonly measured hematological and biochemical parameters in 6-wk-old pigs will be useful. The reference intervals calculated in this study will aid in the diagnosis and monitoring of both naturally occurring and experimentally induced disease. In comparison to published reference intervals for older non SPF pigs, notable differences in leukocyte populations, and in levels of sodium, potassium, glucose, protein, and alkaline phosphatase were observed.展开更多
基金funded by Jilin Province Science and Technology Development Plan Project,grant number 20220203163SF.
文摘With the increasing integration of large-scale distributed energy resources into the grid,traditional distribution network optimization and dispatch methods struggle to address the challenges posed by both generation and load.Accounting for these issues,this paper proposes a multi-timescale coordinated optimization dispatch method for distribution networks.First,the probability box theory was employed to determine the uncertainty intervals of generation and load forecasts,based on which,the requirements for flexibility dispatch and capacity constraints of the grid were calculated and analyzed.Subsequently,a multi-timescale optimization framework was constructed,incorporating the generation and load forecast uncertainties.This framework included optimization models for dayahead scheduling,intra-day optimization,and real-time adjustments,aiming to meet flexibility needs across different timescales and improve the economic efficiency of the grid.Furthermore,an improved soft actor-critic algorithm was introduced to enhance the uncertainty exploration capability.Utilizing a centralized training and decentralized execution framework,a multi-agent SAC network model was developed to improve the decision-making efficiency of the agents.Finally,the effectiveness and superiority of the proposed method were validated using a modified IEEE-33 bus test system.
文摘BACKGROUND Pepsinogen(PG)and the PG I/II ratio(PGR)are critical indicators for diagnosing Helicobacter pylori infection and chronic atrophic gastritis,and assessing gastric cancer risk.Existing reference intervals(RIs)often overlook age,sex,and demographic variations.Partitioned RIs,while considering these factors,fail to capture the gradual age-related physiological changes.Next-generation RIs offer a solution to this limitation.AIM To investigate age-and sex-specific dynamics of PG and establish next-generation RIs for adults and the elderly in northern China.METHODS After screening,708 healthy individuals were included in this observational study.Serum PG was measured using chemiluminescence immunoassay.Age-and sex-related effects on PG were analyzed with a two-way analysis of variance.RI partitioning was determined by the standard deviation ratio(SDR).Traditional RIs were established using a non-parametric approach.Generalized Additive Models for Location,Scale,and Shape(GAMLSS)modeled age-related trends and continuous reference percentiles for PG I and PG II.Reference limit flagging rates for both RI types were compared.RESULTS PG I and PG II levels were influenced by age(P<0.001)and sex(P<0.001),while PGR remained stable.Age-specific RIs were required for PG I(SDR=0.366)and PG II(SDR=0.424).Partitioned RIs were established for PG I and PG II,with a single RI for PGR.GAMLSS modeling revealed distinct age-dependent trajectories:PG I increased from a median of 39.75μg/L at age 20 years to 49.75μg/L at age 60 years,a 25.16%increase,after which it plateaued through age 80 years.In contrast,PG II showed a continuous rise throughout the age range,with the median value increasing from 5.07μg/L at age 20 years to 8.36μg/L at age 80 years,corresponding to a 64.89%increase.Continuous reference percentiles intuitively reflected these trends and were detailed in this study.Next-generation RIs demonstrated superior accuracy compared to partitioned RIs when applied to specific age subgroups.CONCLUSION This study elucidates the age-and sex-specific dynamics of PG and,to our knowledge,is the first to establish next-generation RIs for PG,supporting more individualized interpretation in laboratory medicine.
基金supported by the Key Discipline Program of the Fifth Round of the Three-Year Public Health Action Plan(2020-2022 Year)of Shanghai,China(GWV-10.1-XK08).
文摘Objectives:This study aimed to explore the perceptions and recommendations of multiparas and health-related professionals regarding appropriate birth intervals(Bis)and key determinants.Methods:In-depth semi-structured interviews were conducted between April 1 and June 30,2022.Nine multiparas and thirteen health-related professionals were purposefully sampled until data saturation was reached.A thematic analysis approach was applied to the interview transcripts,utilizing dual independent coding and consensus validation in NVivo 12.0.Results:The data generated two overarching categories:1)balanced decision-making on the appropriate birth intervals and 2)internal and external determinants integrated with health and societal considerations.Four key themes emerged following the two categories:1)consistency and discrepancy between the actual and recommended birth intervals of multiparas;2)health-and developmentoriented professional recommendations;3)internal determinants related to individual-level factors;and 4)external determinants related to child-related factors,family support,and social security.Weighing women's reproductive health and career development,multiparas and health-related professionals perceived a length between 18 and 36 months as the appropriate Bl.Conclusion:Multiparas and health-related professionals shaped their balanced recommendations on a relatively appropriate birth interval ranging from 18 to 36 months,which was influenced by women's individual-level factors,child-related factors,family support,and social security.Targeted social and healthcare services should be offered to women and their families during the Bls.
文摘Objective:To evaluate the effectiveness of DTwP-HB-Hib vaccination dosing intervals at eight weeks versus four weeks on the immunogenicity of the diphtheria component.Methods:This is a randomized,open-label,parallel,controlled trial on healthy two-month-old infants who had not received DTwP-HB-Hib vaccinations.The infants received three doses of the vaccine either at an eight-week or four-week interval.The anti-diphtheria toxoid IgG antibody levels before and after three doses of the vaccination were measured using ELISA.Results:Eighty infants were enrolled in this study,with 64 fulfilling the study requirements and randomized into two groups.All study participants exhibited uncertain protection against diphtheria antibodies(0.01-0.99 IU/mL)at the beginning of the study with an average of(0.023±0.009)IU/mL and(0.026±0.009)IU/mL in eight weeks and four weeks groups.Following three doses of the vaccination,the antibody level rose to an average of(1.320±0.234)IU/mL in the eight-week group and(1.307±0.186)IU/mL in the four-week group,with no statistically significant difference in the antibody levels observed(P=0.814).Conclusions:DTwP-HB-Hib vaccinations can be administered at an eight-week or four-week interval,as they do not significantly affect the level of anti-diphtheria IgG antibodies.
文摘BACKGROUND The reference ranges for biochemical parameters can fluctuate due to factors like altitude,age,gender,and socioeconomic conditions.These values are crucial for interpreting laboratory data and guide clinical treatment decisions.Currently,there is no established set of reference intervals for cord blood biochemical parameters of newborns in India,particularly in Mumbai.AIM To create cord blood biochemical parameters reference intervals specifically for Mumbai,India.METHODS A cross-sectional study was conducted in an Indian tertiary care hospital.This study focused on healthy newborns with normal birth weight,born to pregnant mothers without health issues.Cord blood samples,approximately 2-3 mL in volume,were collected from 210 term neonates.These samples were divided into fluoride(glucose)and clot activator(serum)tubes and were subsequently analyzed in the institute's biochemical laboratory.The data obtained from the analysis was then subjected to statistical analysis.The result of the Shapiro-Wilk test suggested non-normality in the data distribution.Consequently,nonparametric statistics were utilized for analysis.The Mann-Whitney U test was utilized to compare parameter distributions among different factors,including the infant’s sex,delivery method,maternal age,and obstetric history.A significance level of P<0.05 was considered to indicate statistical significance.RESULTS The following represent the median figures and central 95 percentile reference intervals for biochemical parameters in umbilical cord blood of newborns:Serum direct bilirubin=(0.1-0.55)mg/dL,indirect bilirubin=(0.64-2.26)mg/dL,total bilirubin=(0.62-3.14)mg/dL,creatinine=(0.27-0.76)mg/dL,sodium=(128.19-143.26)mmol/L,chloride=(100.19-111.68)mmol/L,potassium=(1.62-9.98)mmol/L and plasma glucose=(24.75-94.23)mg/dL.Statistically significant differences were observed in serum sodium,potassium,and plasma glucose levels when comparing delivery modes.CONCLUSION This is the pioneering study in which first time,the biochemical reference intervals in cord blood for newborns are established in western India.The values are applicable for newborns from this area.Larger study throughout the country is required.
基金supported by the Colombian government through COLCIENCIA scholarships,National Doctoral Program,Call 727 of 2015C.Castro gratefully acknowledges partial financial support from the Centro de Matematica da Universidade do Minho(CMAT/UM),through UID/00013V.Leiva acknowledges funding from the Agencia Nacional de Investigacion y Desarrollo(ANID)of the Chilean Ministry of Science,Technology,Knowledge and Innovation,through FONDECYT project grant 1200525.
文摘Most reliability studies assume large samples or independence among components,but these assump-tions often fail in practice,leading to imprecise inference.We address this issue by constructing confidence intervals(CIs)for the reliability of two-component systems with Weibull distributed failure times under a copula-frailty framework.Our construction integrates gamma-distributed frailties to capture unobserved heterogeneity and a copula-based dependence structure for correlated failures.The main contribution of this work is to derive adjusted CIs that explicitly incorporate the copula parameter in the variance-covariance matrix,achieving near-nominal coverage probabilities even in small samples or highly dependent settings.Through simulation studies,we show that,although traditional methods may suffice with moderate dependence and large samples,the proposed CIs offer notable benefits when dependence is strong or data are sparse.We further illustrate our construction with a synthetic example illustrating how penalized estimation can mitigate the issue of a degenerate Hessian matrix under high dependence and limited observations,so enabling uncertainty quantification despite deviations from nominal assumptions.Overall,our results fill a gap in reliability modeling for systems prone to correlated failures,and contribute to more robust inference in engineering,industrial,and biomedical applications.
文摘Purpose–The deformation of the roadbed is easily influenced by the external environment to improve the accuracy of high-speed railway subgrade settlement prediction.Design/methodology/approach–A high-speed railway subgrade settlement interval prediction method using the secretary bird optimization(SBOA)algorithm to optimize the BP neural network under the premise of gray relational analysis is proposed.Findings–Using the SBOA algorithm to optimize the BP neural network,the optimal weights and thresholds are obtained,and the best parameter prediction model is combined.The data were collected from the sensors deployed through the subgrade settlement monitoring system,and the gray relational analysis is used to verify that all four influencing factors had a great correlation to the subgrade settlement,and the collected data are verified using the model.Originality/value–The experimental results show that the SBOA-BP model has higher prediction accuracy than the BP model,and the SBOA-BP model has a wider range of prediction intervals for a given confidence level,which can provide higher guiding value for practical engineering applications.
基金supported by the National Key Research and Development Program of China(2023YFB3307801)the National Natural Science Foundation of China(62394343,62373155,62073142)+3 种基金Major Science and Technology Project of Xinjiang(No.2022A01006-4)the Programme of Introducing Talents of Discipline to Universities(the 111 Project)under Grant B17017the Fundamental Research Funds for the Central Universities,Science Foundation of China University of Petroleum,Beijing(No.2462024YJRC011)the Open Research Project of the State Key Laboratory of Industrial Control Technology,China(Grant No.ICT2024B70).
文摘The distillation process is an important chemical process,and the application of data-driven modelling approach has the potential to reduce model complexity compared to mechanistic modelling,thus improving the efficiency of process optimization or monitoring studies.However,the distillation process is highly nonlinear and has multiple uncertainty perturbation intervals,which brings challenges to accurate data-driven modelling of distillation processes.This paper proposes a systematic data-driven modelling framework to solve these problems.Firstly,data segment variance was introduced into the K-means algorithm to form K-means data interval(KMDI)clustering in order to cluster the data into perturbed and steady state intervals for steady-state data extraction.Secondly,maximal information coefficient(MIC)was employed to calculate the nonlinear correlation between variables for removing redundant features.Finally,extreme gradient boosting(XGBoost)was integrated as the basic learner into adaptive boosting(AdaBoost)with the error threshold(ET)set to improve weights update strategy to construct the new integrated learning algorithm,XGBoost-AdaBoost-ET.The superiority of the proposed framework is verified by applying this data-driven modelling framework to a real industrial process of propylene distillation.
基金Supported by the Icelandic Technological Development Fund(Project No.1910271).
文摘Background Vibrotactile feedback systems are widely used in assistive technology,wearable devices,and virtual environments to deliver precise tactile information.The timing of interstimulus intervals(ISIs)plays a critical role in determining how accurately users perceive and interpret vibrotactile patterns.The optimal use of ISIs can increase the effectiveness of these systems,improve user interaction,and enable reliable,intuitive feedback in diverse applications.We examined how different interstimulus intervals ISIs impact the accuracy of vibrotactile pattern recognition.Methods Participants wore a forearm-mounted device with six voice coil actuators arranged in a 3×2 grid,delivering Braille-based vibrotactile patterns sequentially at ISIs ranging from 10 to 2500 ms.Eight participants performed identification tasks involving Icelandic Braille patterns categorized as either short(2-3 actuators)or long(4-5 actuators).A repeated measures ANOVA was conducted to assess the effects of ISI,pattern type,and practice(across two testing blocks)on pattern recognition accuracy.Results For short patterns,accuracy was highest(92%-98%)at ISIs of 50-700 ms,with peak performance at 300 ms.For long patterns,accuracy reached 86%-94%at ISIs of 100-500 ms,peaking at 400 ms.Participants were more accurate with short patterns,and performance improved significantly over time for both short and long patterns,highlighting the importance of training for vibrotactile pattern recognition.Conclusions These results underscore the importance of careful selection of ISIs in vibrotactile feedback systems for accurate pattern identification.The findings provide valuable insights for conveying tactile information using wearable devices,contributing to better tactile feedback and performance in applications requiring precise vibrotactile information delivery.
基金funded by the Natural Science Foundation of Hunan Province(grant number 2024JJ5283 to XH)。
文摘Preterm birth and suboptimal fetal growth remain significant perinatal challenges worldwide.Recent data indicate that China's perinatal profile has improved due to reductions in preterm birth rates.However,the country has a 6.5%prevalence of small-for-gestational-age(SGA),ranking fifth globally in total SGA birth numbers^([1,2]).
文摘Objective： To evaluate the changes in Tp-e interval （an interval from the peak to the end of the T wave）, QT interval and Tp-e/QT ratio of the body surface ECG in patients with left ventricular hypertrophy （LVH）. Methods： The Tp-e interval and QT interval were measured on body surface ECGs in 42 patients without either hypertension or LVH （control group）, 41 patients having hypertension but not LVH （non-LVH group）, and 38 patients with both hypertension and LVH （LVH group）. Results： The mean corrected QT （QTc） interval, and mean corrected Tp-e[T（p-e）c] interval were significantly longer in the LVH group （0.430±0.021s vs. 0.409±0.019s, p 〈 0.01; 0.098±0.013s vs. 0.088±0.011s, respectively） than those in the control group. The Tp-e/QT ratio was also amplified in LVH group （0.232± 0.028 vs.0.218± 0.027） （p 〈 0.05）. Conclusion： LVH increased the QT interval, Tp-e interval and Tp-e/QT ratio of the body surface ECG.
基金supported by the Grant for State Key Program for Basic Research of China(No.2013CB329405)National Natural Science Foundation of China(No.61573275)+3 种基金Foundation for Innovative Research Groups of the National Natural Science Foundation of China(No.61221063)Science and Technology Project of Shaanxi Province of China(No.2013KJXX-46)Specialized Research Fund for the Doctoral Program of Higher Education of China(20120201120036)Fundamental Research Funds for the Central Universities of China(No.xjj2014122)
文摘In the theory of belief functions, the measure of uncertainty is an important concept, which is used for representing some types of uncertainty incorporated in bodies of evidence such as the discord and the non-specificity. For the non-specificity part, some traditional measures use for reference the Hartley measure in classical set theory; other traditional measures use the simple and heuristic function for joint use of mass assignments and the cardinality of focal elements. In this paper, a new non-specificity measure is proposed using lengths of belief intervals, which represent the degree of imprecision. Therefore, it has more intuitive physical meaning. It can be proved that our new measure can be rewritten in a general form for the non-specificity. Our new measure is also proved to be a strict non-specificity measure with some desired properties. Numerical examples, simulations, the related analyses and proofs are provided to show the characteristics and good properties of the new non-specificity definition. An example of an application of the new non- specificity measure is also presented.
文摘Since the great 1303 Hongtong, Shanxi, earthquake of magnitude 8, 700 years have elapsed. To analyze the long-term seismic potential, this paper divides the Taiyuan-Linfen portion of the Shanxi graben system into 5 seismogenic segments. Based on data of historical earthquakes and GPS observation, the authors estimate mean seismic-moment rates and average recurrence intervals of strong earthquakes for the individual segments, and fur-ther analyze relative levels of current stress cumulation on the segments based on mapping b-values along the gra-ben system by using the network seismic data for the recent over 30 years. The main result shows that the Linfen basin segment has an estimated mean seismic-moment rate of 2.211016 Nm/a to 3.031016 Nm/a, and its average recurrence interval for M=7.5 earthquake is estimated to be between 1 560 and 2 140 years. For the Ling-shi-Hongtong segment, the estimated average recurrence interval for M=8 earthquakes is between 4 300 and 5 100 years, equivalent to having a mean moment-rate of 2.581016 Nm/a to 3.101016 Nm/a. The contour map of b-values shows that the two segments of Lingshi-Hongtong and Linfen basin have been being at low or relatively low stress levels, reflecting that since the 1303 M=8 and the 1695 M=7.5 earthquake ruptures, the fault-planes strengths of the both segments have not been resumed yet. And the other two segments, the Houma and the Jiexiu-Fenyang, have relatively high stress levels, and have been already identified as potential risky segments for the coming earthquakes from the analysis combining with the estimated average recurrence intervals of earth-quakes on the both segments.
文摘Objectives To assess the impacts of public health interventions on the outbreak of SARS in Beijing by analyzing the intervals between symptom onset, hospital admission and notification of its cases. Methods Data of SARS cases reported from the Beijing Municipal Centers for Disease Prevention and Control (BCDC) were collected and analyzed by descriptive epidemiology. Results In the early epidemic period, the intervals between the disease onset and the hospital admission seemed irregular, so was the intervals between the hospital admission and the notification. After the middle ten days of April, the intervals turned out to be more regular, and the disordered situation in terms of the hospital admission and the case notification was gradually brought under control. Conclusions Public health interventions against SARS has revealed positive impacts on SARS control program in Beijing. The timing and sensitivity of epidemic information reporting systems has been greatly improved in Beijing as a result of successful fight against this disease.
基金co-funded by National Natura Science Foundation of China (Grant No. 41102058 Gran No. U1262203)+4 种基金the National Science and Technology Special Grant (No. 2011ZX05006-003)Shandong Natura Science Foundation (Grant No. ZR2011DQ017)the Fundamental Research Funds for the Central Universities (No. 12CX04001A No. 13CX02035A No. 13CX02036A)
文摘Methodologies have been developed for calculating cutoffs of reservoir intervals with production capacity （RIPC） and reservoir intervals with accumulation capacity （RIAC） according to the types of pore throat structures and dynamic force by using data from petrophysical analysis, production tests and mercury injection. The data are from clastic reservoirs in the third member （Es3） and the fourth member （Es4） of the Shahejie Formation in the Shengtuo area on the North Slope of the Dongying Sag, Jiyang Depression, China. The method of calculating cutoffs of RIPC is summarized as follows： 1） determination of permeability cutoffs of RIPC; 2） classification of types of pore-throat structures according to mercury injection data and then relating porosity to permeability and determining the relationship between porosity and permeability according to each type of pore-throat structure; and 3） calculating porosity cutoffs of RIPC using established correlation between porosity and permeability according to the type of pore throat structure. The method of calculating cutoffs of RIAC includes： 1） establishing a functional relationship between oil-water interracial tension and formation temperature; 2） calculating limiting values of maximum connected pore-throat radii according to formation temperature and dynamic forces of each reservoir interval; 3） correlating permeability with maximum connected pore-throat radius and then obtaining permeability cutoffs of RIAC; and 4） calculating porosity cutoffs on the basis of permeability cutoffs according to specific correlations, suitable for the type of porethroat structure. The results of this study show that porosity and permeability cutoffs of clastic reservoirs decrease with depth. For a fixed permeability cutoff, the porosity cutoff of R1PC varies because the type of pore throat is different. At a fixed temperature, porosity and permeability cutoffs of RIAC decrease as dynamic force increases. For a fixed permeability cutoff of effective hydrocarbon accumulation, the porosity cutoff also varies with different types of pore throat.
基金Financial support for this work, provided by the National Natural Science Foundation of China (Nos. 50774083 and 41074040)the Program for New Century Excellent Talents in University (No. NCET-07-0803)the National Key Basic Research Program (No. 2009CB219605)
文摘Based on the steady-state seepage method, we used the Mechanical Testing and Simulation 815.02 System and a self-designed seepage instrument for over-broken stone to measure seepage properties of water flows in three types of crushed rock samples. Three methods of confidence interval in describing permeability coefficients are presented: the secure interval, the calculated interval and the systemic interval. The lower bound of the secure interval can be applied to water-inrush and the upper bound can solve the problem of connectivity. For the calculated interval, as the axial pressure increases, the length of confidence interval is shortened and the upper and lower bounds are reduced. For the systemic interval, the length of its confidence interval, as well as the upper and lower bounds, clearly vary under low axial pressure but are fairly similar under high axial pressure. These three methods provide useful information and references for analyzing the permeability coefficient of over-broken rock.
基金supported by the Pre-research Fund (N0901-041)the Funding of Jiangsu Innovation Program for Graduate Education(CX09B 081Z CX10B 110Z)
文摘A novel adaptive sampling interval algorithm for multitarget tracking is presented. This algorithm which is based on interacting multiple models incorporates the grey relational grade （GRG） into the particle swarm optimization （PSO）. Firstly, the desired tracking accuracy is set for each target. Secondly, sampling intervals are selected as particles, and then the advantage of the GRG is taken as the measurement function for resource management. Meanwhile, the fitness value of the PSO is used to measure the difference between desired tracking accuracy and estimated tracking accuracy. Finally, it is suggested that the radar should track the target whose prediction value of the next sampling interval is the smallest. Simulations show that the proposed method improves both the tracking accuracy and tracking efficiency of the phased-array radar.
文摘Objectives:To assess whether the extension of the flushing interval will increase risks of complications associated with totally implantable venous access port(TIVAP)in the off-treatment period.Methods:A retrospective single-center observational study was performed.Patients with a TIVAP in the off-treatment period that underwent regular flushing in our clinic were included.Data concerning patients and their TIVAPs were recorded.Patient baseline characteristics and TIVAP-related complications were analyzed.Continuous variables were analyzed by ANOVA or the Kruskal-Wallis H test.To compare the occurrence of TIVAP-related complications,the chi-square test was used;if needed,Fisher’s exact test was used.Results:Totally 607 patients were reviewed,and 563 patients were finally included.Thirteen complications were recorded,including 11 cases of catheter occlusion(1.95%),one case of port cannula rotation(0.18%),and one case of catheter tip malposition(0.18%).No device-related infection or venous thrombosis was recorded.Among these patients,the average flushing interval was 35.27±13.09 days.Patients were divided into three groups according to the flushing interval:every 28 days or less(Group 1,n=133);every 29-44 days(Group 2,n=350);and every 45 days or more(Group 3,n=80).No significant difference in catheter-related complications was found among the three groups(P>0.05).Conclusions:In the TIVAP off-treatment period,patients without any history of TIVAP-related complications during approximately one year can attempt to prolong the flushing interval to more than 4 weeks;we further suggest that 5-6 weeks may be an appropriate option for these patients.
基金Acknowledgements This work was supported partially by the Beijing Natural Science Foundation under Crant No. 4112048 the Program for New Century Excellent Talents in University under Gant No. NCET-09-0206+4 种基金 the National Natural Science Foundation of China under Crant No. 60830001 the Key Project of State Key Laboratory of Rail Traffic Control and Safety under Crants No. RCS2008ZZ006, No. RCS2011ZZ008 the Program for Changjiang Scholars and Innovative Research Team in University under Crant No. IRT0949 the Project of State Key kab. of Rail Traffic Control and Safety under C~ants No. RCS2008ZT005, No. RCS2010ZT012 the Fundamental Research Funds for the Central Universities under Crants No. 2010JBZ（~8, No. 2011YJS010.
文摘The non-stationary behavior, caused by the train rmverrent, is the rmin factor for the variation of high speed railway channel. To measure the tirce-variant effect, the parameter of stationarity interval, in which the channel keeps constant or has no great change, is adopted based on Zhengzfiou- Xi＇an （Zhengxi） passenger dedicated line measurement with different train speeds. The stationarity interval is calculated through the definition of Local Region of Stationarity （LRS） under three train ve- locities. Furthermore, the time non-stationary characteristic of high speed pared with five standard railway channel is corn- Multiple-Input MultipleOutput （MIMO） channel models, i.e. Spatial Channel Model （SCM）, extended version of SCM （SCME）, Wireless World Initiative New Radio Phase II （WINNERII）, International Mobile Teleconmnications-Advanced （IMT-Advanced） and WiMAX models which contain the high speed moving scenario. The stationarity interval of real channel is 9 ms in 80% of the cases, which is shorter than those of the standard models. Hence the real channel of high speed railway changes more rapidly. The stationarity intervals of standard models are different due to different modeling methods and scenario def- initions. And the compared results are instructive for wireless system design in high speed railway.
文摘Background： Hematologic and biochemical reference intervals depend on many factors, including age. A review of the literature highlights the lack of reference intervals for 6-wk-old specific pathogen free （SPF） Hampshire-Yorkshire crossbred pigs. For translational research, 6-wk-old pigs represent an important animal model for both human juvenile colitis and diabetes mellitus type 2 given the similarities between the porcine and human gastrointestinal maturation process. The aim of this study was to determine reference intervals for hematological and biochemical parameters in healthy 6-wk-old crossbred pigs. Blood samples were collected from 66 clinically healthy Hampshire-Yorkshire pigs. The pigs were 6 wks old, represented both sexes, and were housed in a SPF facility. Automated hematological and biochemical analysis were performed using an ADVIA 120 Hematology System and a Cobas 6000 C501 Clinical Chemistry Analyzer. Results： Reference intervals were calculated using both parametric and nonparametric methods. The mean, median, minimum, and maximum values were calculated. Conclusion： As pigs are used more frequently as medical models of human disease, having reference intervals for commonly measured hematological and biochemical parameters in 6-wk-old pigs will be useful. The reference intervals calculated in this study will aid in the diagnosis and monitoring of both naturally occurring and experimentally induced disease. In comparison to published reference intervals for older non SPF pigs, notable differences in leukocyte populations, and in levels of sodium, potassium, glucose, protein, and alkaline phosphatase were observed.
