In the assembly process of large volume product,engineering constraints limit the relative pose of components and serve as a standard for judging assembly quality.However,in the traditional process of target pose esti...In the assembly process of large volume product,engineering constraints limit the relative pose of components and serve as a standard for judging assembly quality.However,in the traditional process of target pose estimation,a general method is needed for establishing the correlation between engineering constraints and product pose,and it is difficult to evaluate pose by constraints comprehensively.Therefore,the process of target pose estimation and evaluation is separated.In this paper,a pose coordination model based on multi-constraints is proposed,which includes pre-processing,pose estimation,pose adjustment and evaluation.Firstly,engineering constraints are decoupled into 4 types of Minimum Geometrical Reference Constraints(MGRC),and the inequalities for solving target pose are formulated.Then the Constraint Coordination Index(CCI)is defined as the optimization objective to solve the target pose.Finally,with CCI as the numerical index,the target pose is evaluated to illustrate the quality of assembly.Taking the simulation experiment of wing-fuselage jointing as an example,the external and internal parameters of model are analyzed,and the pose estimation based on multi-constraints reduces the CCI by 12%,compared with the point-set-registration method.展开更多
We used data from the Xinjiang Digital Seismic Network and PSD( Power Spectral Density) method to perform noise level assessment for six stations. We calculated the median of the power spectral density to evaluate the...We used data from the Xinjiang Digital Seismic Network and PSD( Power Spectral Density) method to perform noise level assessment for six stations. We calculated the median of the power spectral density to evaluate the noise level of different stations. After the comparison of the power spectral density of different stations and the airgun signal recognition,we found that noise level of stations with recognizable airgun source signals is lower than that of stations without recognizable signals. The largest difference of the power spectral density is 40 d B,and the smallest is 15 d B. Finally,we found that the failure to recognize the signal of airgun sources at some stations is due to the noise level.展开更多
As this is the first time a large volume airgun has been excited in the "Yangtse River Geoscience Project",it is necessary to study the time-frequency characteristic based on the linear stacked seismic data ...As this is the first time a large volume airgun has been excited in the "Yangtse River Geoscience Project",it is necessary to study the time-frequency characteristic based on the linear stacked seismic data from records from portable stations near the fixed fields and seismic stations. Airgun signal propagation distances were detected using stacked seismic data to analyze the environmental impact on signal propagation distance. The results showed that:( 1) the airgun signal produced by bubble pulses,pressure pulses and the surface wave can be received by a portable station near the fixed field;( 2) the dominant frequency of a bubble at 5Hz or so can be received by both near-field stations and far-field stations,pressure pulses rapidly weaken and the dominant frequency bands get narrower as epicentral distance increases;( 3) the longest spread distance of signal is 260 km,the nearest is 180 km,and the signal can travel further in the evening.展开更多
With volume size increasing, it is necessary to develop a highly efficient compression algorithm, which is suitable for progressive refinement between the data server and the browsing client. For three-dimensional lar...With volume size increasing, it is necessary to develop a highly efficient compression algorithm, which is suitable for progressive refinement between the data server and the browsing client. For three-dimensional large volume data, an efficient hierarchical algorithm based on wavelet compression was presented, using intra-band dependencies of wavelet coefficients. Firstly, after applying blockwise hierarchical wavelet decomposition to large volume data, the block significance map was obtained by using one bit to indicate significance or insignificance of the block. Secondly, the coefficient block was further subdivided into eight sub-blocks if any significant coefficient existed in it, and the process was repeated, resulting in an incomplete octree. One bit was used to indicate significance or insignificance, and only significant coefficients were stored in the data stream. Finally, the significant coefficients were quantified and compressed by arithmetic coding. The experimental results show that the proposed algorithm achieves good compression ratios and is suited for random access of data blocks. The results also show that the proposed algorithm can be applied to progressive transmission of 3D volume data.展开更多
For samples in the gaseous state at room temperature and ambient pressure,mature technology has been developed to encapsulate them in a diamond anvil cell(DAC).However,the large volume press(LVP)can only treat samples...For samples in the gaseous state at room temperature and ambient pressure,mature technology has been developed to encapsulate them in a diamond anvil cell(DAC).However,the large volume press(LVP)can only treat samples with starting materials in solid or liquid form.We have achieved stable encapsulation and reaction treatment of carbon dioxide in a centimeter sized sample chamber for a long time(over 10 min)under conditions of temperature higher than 1200℃ and pressure over 5 GPa through the use of integrated low-temperature freezing and rapid compression sealing method for LVP cell assemblies.This technology can also be applied to the packaging of other gaseous or liquid samples,such as ammonia,sulfur dioxide,water,etc.in LVP devices.展开更多
BACKGROUND Refractory ascites has a 1-year survival rate of 50%.In selected patients,treatment options include liver transplantation(LT)or transjugular intrahepatic portosystemic stent shunt(TIPSS).AIM To assess the o...BACKGROUND Refractory ascites has a 1-year survival rate of 50%.In selected patients,treatment options include liver transplantation(LT)or transjugular intrahepatic portosystemic stent shunt(TIPSS).AIM To assess the outcomes of patients who underwent a TIPSS compared to large volume paracentesis(LVP).METHODS Retrospective study of patients who underwent a covered TIPSS or LVP for refractory or recurrent ascites over 7 years.Primary outcome was transplant-free survival(TFS).Further analysis was done with propensity score matching(PSM).RESULTS There were 150 patients[TIPSS group(n=75),LVP group(n=75)].Seven patients in the TIPSS group underwent LT vs 22 patients in the LVP group.Overall median follow up,20(0.47-179.53)mo.In the whole cohort,there was no difference in TFS[hazard ratio(HR):0.80,95%confidence interval(CI):0.54-1.21];but lower de novo hepatic encephalopathy with LVP(HR:95%CI:0.20-0.96).These findings were confirmed following PSM analysis.On multivariate analysis albumin and hepatocellular carcinoma at baseline were associated with TFS.CONCLUSION Covered TIPSS results in similar TFS compared to LVP in cirrhotic patients with advanced liver failure.Liver transplant assessment should be considered in all potential candidates for TIPSS.Further controlled studies are recommended to select appropriate patients for TIPSS.展开更多
in this paper,we prove that a complete n-dimensional Riemannian manifold with nonnegative kth-Ricci curvature, large volume growth has finite topological type provided that lim r→∞{（vol[B（p.r]/ωnrn-αM）rk（n-1...in this paper,we prove that a complete n-dimensional Riemannian manifold with nonnegative kth-Ricci curvature, large volume growth has finite topological type provided that lim r→∞{（vol[B（p.r]/ωnrn-αM）rk（n-1）/k＋1（1-α/2）}≤for some COllstant ε〉0 We also prove that a conlplete Riemannian manifold with nonnegative kth-Ricci curvature and undler some pinching conditions is diffeomorphic to R^n.展开更多
Construction of mass concrete structures face more challenges in temperature difference and complex stress under low temperature than the ambient temperature. It has been proved by the practice that, not only improvin...Construction of mass concrete structures face more challenges in temperature difference and complex stress under low temperature than the ambient temperature. It has been proved by the practice that, not only improving tensile strength of structural concrete as soon as possible and removing of constrain as much as possible, but also calculation of the thermal stress in the process of construction and maintenance, controlling structure of concrete tensile strength and temperature difference stress ratio can ensure the safety and defect-free.展开更多
Objective: to explore the application value of whole-course nursing in the treatment of pneumoconiosis patients with whole lung lavage by bronchoscope. Methods: 30 patients with pneumoconiosis admitted to our hospital...Objective: to explore the application value of whole-course nursing in the treatment of pneumoconiosis patients with whole lung lavage by bronchoscope. Methods: 30 patients with pneumoconiosis admitted to our hospital from January 2017 to January 2022 were selected as the research object. According to the implementation of the nursing plan, they were divided into the whole-course group and the routine group, with 15 patients in each group. The lung function, arterial blood oxygen partial pressure index, postoperative recovery and psychological state of the two groups were compared. Results: the comparison of pulmonary function and arterial oxygen partial pressure index before treatment between the whole course group and the conventional group had statistical significance (P > 0.05). After treatment, it was better than before, and the whole course group was better than the control group (p < 0.05). Compared with the control group, the ambulation time, extubation time and hospitalization time of the whole group were lower. Compared with the conventional group, the pain score was higher (p < 0.05). Compared with the normal group, the psychological state score was higher (p < 0.05). Conclusion: during the period of treating pneumoconiosis with bronchoscope whole lung large volume lavage, complete nursing can improve the disease index of patients, accelerate the recovery of patients' symptoms, and reduce patients' negative emotions.展开更多
Large volume airgun arrays have been widely used in exploring and monitoring underground structures for nearly a decade.Nowadays,large volume airgun arrays adopt the synchronous excitation mode,and source characterist...Large volume airgun arrays have been widely used in exploring and monitoring underground structures for nearly a decade.Nowadays,large volume airgun arrays adopt the synchronous excitation mode,and source characteristics are controlled by the source signal of a single airgun,which to some extent limits its application.In order to realize the asynchronous excitation of the airgun array,we developed a new firing system for the airgun array,and carried out a field experiment in the Binchuan Fixed Airgun Signal Transmission station to study the influences of the asynchronous excitation on the source signal.The experimental results show that:the newly developed airgun array firing system can ignite the airguns according to the setting time series with high precision.By designing the excitation time series,the asynchronous excitation can enhance the energy of airgun source signal at 3-5 Hz,and reduce the energy of pressure pulse wave at 6-18 Hz.The signal detection capability of the asynchronous excitation with time series mode is equivalent to the synchronous excitation.展开更多
The ability to generate high pressures in a large-volume press(LVP)is crucial for the study of matter under extreme conditions.Here,we have achieved ultrahigh pressures of and 50 GPa,respectively,at room temperature a...The ability to generate high pressures in a large-volume press(LVP)is crucial for the study of matter under extreme conditions.Here,we have achieved ultrahigh pressures of and 50 GPa,respectively,at room temperature and a high temperature of 1900 K∼60within a millimeter-sized sample volume in a Kawai-type LVP(KLVP)using hard tungsten carbide(WC)and newly designed assem-blies.The introduction of electroconductive polycrystalline boron-doped diamond and dense alumina wrapped with Cu foils into a large conventional cell assembly enables the detection of resistance variations in the Fe_(2)O_(3) pressure standard upon compression.The efficiency of pressure generation in the newly developed cell assembly equipped with conventional ZK10F WC anvils is significantly higher than that of conventional assemblies with some ultrahard or tapered WC anvils.Our study has enabled the routine gener-ation of pressures exceeding 50 GPa within a millimeter-sized sample chamber that have been inaccessible with traditional KLVPs.This advance in high-pressure technology not only breaks a record for pressure generation in traditional KLVPs,but also opens up new avenues for exploration of the properties of the Earth’s deep interior and for the synthesis of novel materials at extreme high pressures.展开更多
Model evaluation using benchmark datasets is an important method to measure the capability of large language models(LLMs)in specific domains,and it is mainly used to assess the knowledge and reasoning abilities of LLM...Model evaluation using benchmark datasets is an important method to measure the capability of large language models(LLMs)in specific domains,and it is mainly used to assess the knowledge and reasoning abilities of LLMs.Therefore,in order to better assess the capability of LLMs in the agricultural domain,Agri-Eval was proposed as a benchmark for assessing the knowledge and reasoning ability of LLMs in agriculture.The assessment dataset used in Agri-Eval covered seven major disciplines in the agricultural domain:crop science,horticulture,plant protection,animal husbandry,forest science,aquaculture science,and grass science,and contained a total of 2283 questions.Among domestic general-purpose LLMs,DeepSeek R1 performed best with an accuracy rate of 75.49%.In the realm of international general-purpose LLMs,Gemini 2.0 pro exp 0205 standed out as the top performer,achieving an accuracy rate of 74.28%.As an LLMs in agriculture vertical,Shennong V2.0 outperformed all the LLMs in China,and the answer accuracy rate of agricultural knowledge exceeded that of all the existing general-purpose LLMs.The launch of Agri-Eval helped the LLM developers to comprehensively evaluate the model's capability in the field of agriculture through a variety of tasks and tests to promote the development of the LLMs in the field of agriculture.展开更多
This study demonstrates a novel integration of large language models,machine learning,and multicriteria decision-making to investigate self-moderation in small online communities,a topic under-explored compared to use...This study demonstrates a novel integration of large language models,machine learning,and multicriteria decision-making to investigate self-moderation in small online communities,a topic under-explored compared to user behavior and platform-driven moderation on social media.The proposed methodological framework(1)utilizes large language models for social media post analysis and categorization,(2)employs k-means clustering for content characterization,and(3)incorporates the TODIM(Tomada de Decisão Interativa Multicritério)method to determine moderation strategies based on expert judgments.In general,the fully integrated framework leverages the strengths of these intelligent systems in a more systematic evaluation of large-scale decision problems.When applied in social media moderation,this approach promotes nuanced and context-sensitive self-moderation by taking into account factors such as cultural background and geographic location.The application of this framework is demonstrated within Facebook groups.Eight distinct content clusters encompassing safety,harassment,diversity,and misinformation are identified.Analysis revealed a preference for content removal across all clusters,suggesting a cautious approach towards potentially harmful content.However,the framework also highlights the use of other moderation actions,like account suspension,depending on the content category.These findings contribute to the growing body of research on self-moderation and offer valuable insights for creating safer and more inclusive online spaces within smaller communities.展开更多
AIM:To investigate the clinical characteristics and treatment outcomes,including visual function and overall survival(OS)of patients with ocular adnexal diffuse large B-cell lymphoma(OA-DLBCL).METHODS:This retrospecti...AIM:To investigate the clinical characteristics and treatment outcomes,including visual function and overall survival(OS)of patients with ocular adnexal diffuse large B-cell lymphoma(OA-DLBCL).METHODS:This retrospective cohort study enrolled 29 patients diagnosed with OA-DLBCL based on histopathological biopsy between 2006 and 2023.Patients were stratified into two subgroups:primary OA-DLBCL(no prior history of lymphoma)and secondary OA-DLBCL(history of DLBCL at non-ocular adnexal sites).OS was defined as the time interval from OA-DLBCL diagnosis to death from any cause.Survival analysis was performed using the Kaplan–Meier method,and prognostic factors affecting OS were identified using multivariate Cox proportional hazards regression with a stepwise selection approach.RESULTS:The cohort included 24 patients with primary OA-DLBCL(13 males,11 females;mean age:61.36±18.29y)and 5 patients with secondary OA-DLBCL(2 males,3 females;mean age:50.94±18.17y).Among the primary OA-DLBCL subgroup,12 patients(50%)presented with advanced disease(Ann Arbor stage IIIE–IV),and 16 patients(66%)were classified as T4 disease according to the tumor-node-metastasis(TNM)staging system.The mean final visual acuity was 1.72±1.10 in the primary group and 0.90±1.18 in the secondary group.The 5-year OS rate for the entire cohort was 27.7%.Multivariate analysis identified five factors significantly associated with poor survival outcomes:epiphora[adjusted hazard ratio(aHR),36.95],atherosclerotic cardiovascular disease(aHR,10.08),human immunodeficiency virus(HIV)infection(aHR,12.47),M1 stage(aHR,6.99),and secondary OA-DLBCL(aHR,6.03;all P<0.05).The median OS was 1.68y for primary OA-DLBCL and 1.12y for secondary OA-DLBCL.CONCLUSION:A substantial proportion of patients with primary OA-DLBCL present with advanced-stage disease at diagnosis.Epiphora,atherosclerotic cardiovascular disease,HIV infection,M1 stage,and secondary OA-DLBCL are independent prognostic factors for poor survival outcomes.These findings emphasize the urgent need for optimized therapeutic strategies and early screening protocols to improve the management of OA-DLBCL,particularly in developing countries.展开更多
The 2024 MRE HP Special Volume selects papers on new theoretical and experimental developments in the use of static largevolume presses(LVPs)1–3 and dynamic compression4,5 for studies under extreme high-pressure and ...The 2024 MRE HP Special Volume selects papers on new theoretical and experimental developments in the use of static largevolume presses(LVPs)1–3 and dynamic compression4,5 for studies under extreme high-pressure and high-temperature(HPHT)conditions.It also continues the previous year’s6 contemporary focus on superhydrides7–11 with extremely high superconducting temperatures Tc and addresses some controversial issues.12–14 In addition,it explores unconventional pressure-induced chemistry,particularly novel chemical stoichiometry and its impact on geochemistry and cosmochemistry in the deep interiors of Earth and other planets.18–21.展开更多
Through improving the aging process during synthesis of the support, γ-Al2O3 with large pore volume and high surface area was synthesized by a facile secondary reforming method. The synthesis parameters, such as the ...Through improving the aging process during synthesis of the support, γ-Al2O3 with large pore volume and high surface area was synthesized by a facile secondary reforming method. The synthesis parameters, such as the reaction temperature, the first aging temperature and the second aging temperature, were investigated. The textural properties of γ-Al2O3 were characterized by means of N2 adsorption-desorption isotherms, X-ray powder diffractometry （XRD）, scanning electron microscopy （SEM）, Fourier transform infrared （FTIR） spectroscopy and thermogravimetry （TG）. The experimental results indicated that AACH and amorphous A1OOH were the precursors of alumina, which were formed via precipitation from solutions after reaction of aluminum sulphate with ammonium hydrogen carbonate. The precursor nanocrystallites grew and re-assembled during the secondary reforming process, which resulted in an increased pore size and pore volume and a decreased bulk density. The as-synthesized γ-Al2O3 materials featured meso/macroporosity, large pore volume （2.175 cm^3/g）, high surface area （237.8 m^2/g）, and low bulk density （0.284 g/mL）.展开更多
This paper studies the imminent anomalies observed by the Sacks volume strainmeter in Erzhangying station and Tiantanghe station before 80 earthquakes with Ms≥ 7. 0 which took place from January 2011 to April 2014 al...This paper studies the imminent anomalies observed by the Sacks volume strainmeter in Erzhangying station and Tiantanghe station before 80 earthquakes with Ms≥ 7. 0 which took place from January 2011 to April 2014 all over the world. Then, preconditions for anomaly identification are put forward for complex earthquake cases. Statistical results show that volume strain observation has a better earthquake reflecting ability for earthquakes with magnitudes larger than 7. 0 and epicentral distance within 8000kin. In addition, these results also reflect that the volume strain observation can better reflect precursory anomalies of such earthquakes. Based on categorization and description of those anomalies, we divide the anomalies into three types, that is, earth tide distortion type, abrupt change type and slow earthquake type. Furthermore, the paper makes a statistical analysis of these types and preliminarily discusses their mechanical properties as well. According to research, volume strain anomaly has an indicative significance to future strong earthquakes in the world.展开更多
Rheological properties of large particulate-liquid model food systems were studied by using the BMS （ball measuring system）. The model food systems were composed of alginate gel particles （-10mm） and a gelatinised...Rheological properties of large particulate-liquid model food systems were studied by using the BMS （ball measuring system）. The model food systems were composed of alginate gel particles （-10mm） and a gelatinised starch solution with 1% w/w sodium chloride as a liquid phase. The effects of particle phase volume （Ф, 0-0.60）, particle shapes （cube, sphere, rod and disc） and starch concentrations （3% and 5% w/w starch） were investigated. The power law model was successfully applied to characterize the flow properties of each system and the consistency K and power law index n were obtained. The K increased and n decreased with increasing # for samples at all particle shapes at 3% w/w starch in the liquid phase. The particle effect on the viscosity is further analysed by means of the Krieger-Dougherty model and the maximum packing fraction #,, and the intrinsic viscosity [η] were obtained in each system. The Фm, depended on the particle shape, as expected. The [7] value depended on particle shape and was largely in the order of 4.04 （cube）, 3.28 （disc）, 2.56 （sphere） and 2.32 （rod） at 3% w/w starch. The [η] also depended on starch concentration and was 1.1 at 5%,6 w/w starch in the liquid phase with spherical particles. The present results show successful application of BMS to study the rheological properties of large particulate liquid food systems at relatively small scale experiment （-0.5 L） and also that existing models for suspension rheology are applicable for such food systems to a great extend.展开更多
Correlation analysis between the hematological parameters mean corpuscular hemoglobin (MCH) and mean corpuscular volume (MCV) for thalassemia screening in large population was discussed. A total of 4920 peripheral blo...Correlation analysis between the hematological parameters mean corpuscular hemoglobin (MCH) and mean corpuscular volume (MCV) for thalassemia screening in large population was discussed. A total of 4920 peripheral blood samples of reproductive age persons were collected from Guangdong province of China. The hematological parameters MCH and MCV values of samples were first measured, and then the DNA analyses for thalassemia were conducted. All samples were composed by 4463 non-thalassemia and 457 thalassemia, and among 457 thalassemia samples, 311 were α-thalassemia, 133 were β-thalassemia, and 13 were α & β-thalassemia. In accordance with non-thalassemia, thalassemia, α-thalassemia, β-thalassemia, α & β-thalassemia and the entire group itself, a total of six sample groups were divided. The corresponding correlation coefficients between the measured MCH and MCV values for the six sample groups were 0.880, 0.968, 0.966, 0.962, 0.980 and 0.965 respectively. For the thalassemia carriers, highly significant correlation between MCH and MCV were observed. The fitting equations between MCH and MCV values were also obtained. The results indicated that the feasibility for thalassemia screening using MCV or MCH independently as parameter, and provided suitable strategy to select parameters and models for thalassemia screening in large population.展开更多
The storage, longitudinal distribution and recruitment processes of in-stream large wood (LW) were studied comparing channel segments draining four Chilean mountain catchments with different land use. The segments wer...The storage, longitudinal distribution and recruitment processes of in-stream large wood (LW) were studied comparing channel segments draining four Chilean mountain catchments with different land use. The segments were divided into relatively uniform reaches of different lengths and surveyed for LW (piece dimensions, position in the channel, orientation to flow and aggregation) and stream morphology (slope and bank full channel width and depth) characterizations. LW volume stored in the Pichun, El Toro and Vuelta de Zorra study channels are within the range informed in international researches from streams draining catchments with similar forest covers. However, the 1057 m3/ha of LW stored in Tres Arroyos is extremely high and in the same order of magnitude than the reports from old-growth forests in the Pacific Northwest of USA. The size of the area that can potentially provide wood to streams depends on the wood supply mechanisms within any catchment, and the LW stored in the study segments increases as the size of this area increases. This study aims to contribute to the knowledge on the effects of LW in mountain channels, gathering new information and expanding investigations developed in Chile since 2008. This research was carried out within the framework of Project FONDECYT 11106209.展开更多
基金supported by the Special Research on Civil Aircraft of China(No.MJZ-2017-J-96)the Equipment Pre-research Project of China(No.41423010401)。
文摘In the assembly process of large volume product,engineering constraints limit the relative pose of components and serve as a standard for judging assembly quality.However,in the traditional process of target pose estimation,a general method is needed for establishing the correlation between engineering constraints and product pose,and it is difficult to evaluate pose by constraints comprehensively.Therefore,the process of target pose estimation and evaluation is separated.In this paper,a pose coordination model based on multi-constraints is proposed,which includes pre-processing,pose estimation,pose adjustment and evaluation.Firstly,engineering constraints are decoupled into 4 types of Minimum Geometrical Reference Constraints(MGRC),and the inequalities for solving target pose are formulated.Then the Constraint Coordination Index(CCI)is defined as the optimization objective to solve the target pose.Finally,with CCI as the numerical index,the target pose is evaluated to illustrate the quality of assembly.Taking the simulation experiment of wing-fuselage jointing as an example,the external and internal parameters of model are analyzed,and the pose estimation based on multi-constraints reduces the CCI by 12%,compared with the point-set-registration method.
基金jointly funded by the Special Fund of Earthquake Industry(201508008)National Natural Science Foundation of China(41474051)Scientific Institution Innovation and Development Fund of Xinjiang Uygur Autonomous Region(201316)
文摘We used data from the Xinjiang Digital Seismic Network and PSD( Power Spectral Density) method to perform noise level assessment for six stations. We calculated the median of the power spectral density to evaluate the noise level of different stations. After the comparison of the power spectral density of different stations and the airgun signal recognition,we found that noise level of stations with recognizable airgun source signals is lower than that of stations without recognizable signals. The largest difference of the power spectral density is 40 d B,and the smallest is 15 d B. Finally,we found that the failure to recognize the signal of airgun sources at some stations is due to the noise level.
基金jointly sponsored by the Special Fund for Earthquake Scientific Research in the Public Welfare of China Earthquake Administration(2015419015)the National Natural Science Foundation of China(41474071)
文摘As this is the first time a large volume airgun has been excited in the "Yangtse River Geoscience Project",it is necessary to study the time-frequency characteristic based on the linear stacked seismic data from records from portable stations near the fixed fields and seismic stations. Airgun signal propagation distances were detected using stacked seismic data to analyze the environmental impact on signal propagation distance. The results showed that:( 1) the airgun signal produced by bubble pulses,pressure pulses and the surface wave can be received by a portable station near the fixed field;( 2) the dominant frequency of a bubble at 5Hz or so can be received by both near-field stations and far-field stations,pressure pulses rapidly weaken and the dominant frequency bands get narrower as epicentral distance increases;( 3) the longest spread distance of signal is 260 km,the nearest is 180 km,and the signal can travel further in the evening.
基金Supported by Natural Science Foundation of China (No. 60373061).
文摘With volume size increasing, it is necessary to develop a highly efficient compression algorithm, which is suitable for progressive refinement between the data server and the browsing client. For three-dimensional large volume data, an efficient hierarchical algorithm based on wavelet compression was presented, using intra-band dependencies of wavelet coefficients. Firstly, after applying blockwise hierarchical wavelet decomposition to large volume data, the block significance map was obtained by using one bit to indicate significance or insignificance of the block. Secondly, the coefficient block was further subdivided into eight sub-blocks if any significant coefficient existed in it, and the process was repeated, resulting in an incomplete octree. One bit was used to indicate significance or insignificance, and only significant coefficients were stored in the data stream. Finally, the significant coefficients were quantified and compressed by arithmetic coding. The experimental results show that the proposed algorithm achieves good compression ratios and is suited for random access of data blocks. The results also show that the proposed algorithm can be applied to progressive transmission of 3D volume data.
基金supported by the National Key R&D Program of China(Grant No.2023YFA1406200).
文摘For samples in the gaseous state at room temperature and ambient pressure,mature technology has been developed to encapsulate them in a diamond anvil cell(DAC).However,the large volume press(LVP)can only treat samples with starting materials in solid or liquid form.We have achieved stable encapsulation and reaction treatment of carbon dioxide in a centimeter sized sample chamber for a long time(over 10 min)under conditions of temperature higher than 1200℃ and pressure over 5 GPa through the use of integrated low-temperature freezing and rapid compression sealing method for LVP cell assemblies.This technology can also be applied to the packaging of other gaseous or liquid samples,such as ammonia,sulfur dioxide,water,etc.in LVP devices.
文摘BACKGROUND Refractory ascites has a 1-year survival rate of 50%.In selected patients,treatment options include liver transplantation(LT)or transjugular intrahepatic portosystemic stent shunt(TIPSS).AIM To assess the outcomes of patients who underwent a TIPSS compared to large volume paracentesis(LVP).METHODS Retrospective study of patients who underwent a covered TIPSS or LVP for refractory or recurrent ascites over 7 years.Primary outcome was transplant-free survival(TFS).Further analysis was done with propensity score matching(PSM).RESULTS There were 150 patients[TIPSS group(n=75),LVP group(n=75)].Seven patients in the TIPSS group underwent LT vs 22 patients in the LVP group.Overall median follow up,20(0.47-179.53)mo.In the whole cohort,there was no difference in TFS[hazard ratio(HR):0.80,95%confidence interval(CI):0.54-1.21];but lower de novo hepatic encephalopathy with LVP(HR:95%CI:0.20-0.96).These findings were confirmed following PSM analysis.On multivariate analysis albumin and hepatocellular carcinoma at baseline were associated with TFS.CONCLUSION Covered TIPSS results in similar TFS compared to LVP in cirrhotic patients with advanced liver failure.Liver transplant assessment should be considered in all potential candidates for TIPSS.Further controlled studies are recommended to select appropriate patients for TIPSS.
文摘in this paper,we prove that a complete n-dimensional Riemannian manifold with nonnegative kth-Ricci curvature, large volume growth has finite topological type provided that lim r→∞{（vol[B（p.r]/ωnrn-αM）rk（n-1）/k＋1（1-α/2）}≤for some COllstant ε〉0 We also prove that a conlplete Riemannian manifold with nonnegative kth-Ricci curvature and undler some pinching conditions is diffeomorphic to R^n.
文摘Construction of mass concrete structures face more challenges in temperature difference and complex stress under low temperature than the ambient temperature. It has been proved by the practice that, not only improving tensile strength of structural concrete as soon as possible and removing of constrain as much as possible, but also calculation of the thermal stress in the process of construction and maintenance, controlling structure of concrete tensile strength and temperature difference stress ratio can ensure the safety and defect-free.
文摘Objective: to explore the application value of whole-course nursing in the treatment of pneumoconiosis patients with whole lung lavage by bronchoscope. Methods: 30 patients with pneumoconiosis admitted to our hospital from January 2017 to January 2022 were selected as the research object. According to the implementation of the nursing plan, they were divided into the whole-course group and the routine group, with 15 patients in each group. The lung function, arterial blood oxygen partial pressure index, postoperative recovery and psychological state of the two groups were compared. Results: the comparison of pulmonary function and arterial oxygen partial pressure index before treatment between the whole course group and the conventional group had statistical significance (P > 0.05). After treatment, it was better than before, and the whole course group was better than the control group (p < 0.05). Compared with the control group, the ambulation time, extubation time and hospitalization time of the whole group were lower. Compared with the conventional group, the pain score was higher (p < 0.05). Compared with the normal group, the psychological state score was higher (p < 0.05). Conclusion: during the period of treating pneumoconiosis with bronchoscope whole lung large volume lavage, complete nursing can improve the disease index of patients, accelerate the recovery of patients' symptoms, and reduce patients' negative emotions.
基金sponsored by the National Key R&D Program of China(2018YFC1503202)the National Natural Science Foundation of China(41574052,41790463)
文摘Large volume airgun arrays have been widely used in exploring and monitoring underground structures for nearly a decade.Nowadays,large volume airgun arrays adopt the synchronous excitation mode,and source characteristics are controlled by the source signal of a single airgun,which to some extent limits its application.In order to realize the asynchronous excitation of the airgun array,we developed a new firing system for the airgun array,and carried out a field experiment in the Binchuan Fixed Airgun Signal Transmission station to study the influences of the asynchronous excitation on the source signal.The experimental results show that:the newly developed airgun array firing system can ignite the airguns according to the setting time series with high precision.By designing the excitation time series,the asynchronous excitation can enhance the energy of airgun source signal at 3-5 Hz,and reduce the energy of pressure pulse wave at 6-18 Hz.The signal detection capability of the asynchronous excitation with time series mode is equivalent to the synchronous excitation.
基金supported by the National Key R&D Program of China(Grant No.2023YFA1406200)the National Natural Science Foundation of China(Grant Nos.42272041 and 52302043)+2 种基金the National Natural Science Foundation of China(Grant No.U23A20561)the Jilin University High-level Innovation Team Foundation(Grant No.2021TD–05)the Shanghai Synchrotron Radiation Facility(Grant Nos.2024-SSRF-PT-510031 and 505511).
文摘The ability to generate high pressures in a large-volume press(LVP)is crucial for the study of matter under extreme conditions.Here,we have achieved ultrahigh pressures of and 50 GPa,respectively,at room temperature and a high temperature of 1900 K∼60within a millimeter-sized sample volume in a Kawai-type LVP(KLVP)using hard tungsten carbide(WC)and newly designed assem-blies.The introduction of electroconductive polycrystalline boron-doped diamond and dense alumina wrapped with Cu foils into a large conventional cell assembly enables the detection of resistance variations in the Fe_(2)O_(3) pressure standard upon compression.The efficiency of pressure generation in the newly developed cell assembly equipped with conventional ZK10F WC anvils is significantly higher than that of conventional assemblies with some ultrahard or tapered WC anvils.Our study has enabled the routine gener-ation of pressures exceeding 50 GPa within a millimeter-sized sample chamber that have been inaccessible with traditional KLVPs.This advance in high-pressure technology not only breaks a record for pressure generation in traditional KLVPs,but also opens up new avenues for exploration of the properties of the Earth’s deep interior and for the synthesis of novel materials at extreme high pressures.
文摘Model evaluation using benchmark datasets is an important method to measure the capability of large language models(LLMs)in specific domains,and it is mainly used to assess the knowledge and reasoning abilities of LLMs.Therefore,in order to better assess the capability of LLMs in the agricultural domain,Agri-Eval was proposed as a benchmark for assessing the knowledge and reasoning ability of LLMs in agriculture.The assessment dataset used in Agri-Eval covered seven major disciplines in the agricultural domain:crop science,horticulture,plant protection,animal husbandry,forest science,aquaculture science,and grass science,and contained a total of 2283 questions.Among domestic general-purpose LLMs,DeepSeek R1 performed best with an accuracy rate of 75.49%.In the realm of international general-purpose LLMs,Gemini 2.0 pro exp 0205 standed out as the top performer,achieving an accuracy rate of 74.28%.As an LLMs in agriculture vertical,Shennong V2.0 outperformed all the LLMs in China,and the answer accuracy rate of agricultural knowledge exceeded that of all the existing general-purpose LLMs.The launch of Agri-Eval helped the LLM developers to comprehensively evaluate the model's capability in the field of agriculture through a variety of tasks and tests to promote the development of the LLMs in the field of agriculture.
基金funded by the Office of the Vice-President for Research and Development of Cebu Technological University.
文摘This study demonstrates a novel integration of large language models,machine learning,and multicriteria decision-making to investigate self-moderation in small online communities,a topic under-explored compared to user behavior and platform-driven moderation on social media.The proposed methodological framework(1)utilizes large language models for social media post analysis and categorization,(2)employs k-means clustering for content characterization,and(3)incorporates the TODIM(Tomada de Decisão Interativa Multicritério)method to determine moderation strategies based on expert judgments.In general,the fully integrated framework leverages the strengths of these intelligent systems in a more systematic evaluation of large-scale decision problems.When applied in social media moderation,this approach promotes nuanced and context-sensitive self-moderation by taking into account factors such as cultural background and geographic location.The application of this framework is demonstrated within Facebook groups.Eight distinct content clusters encompassing safety,harassment,diversity,and misinformation are identified.Analysis revealed a preference for content removal across all clusters,suggesting a cautious approach towards potentially harmful content.However,the framework also highlights the use of other moderation actions,like account suspension,depending on the content category.These findings contribute to the growing body of research on self-moderation and offer valuable insights for creating safer and more inclusive online spaces within smaller communities.
基金Supported by the Faculty of Medicine,Prince of Songkla University.Wainipitapong S has received grants from the Faculty of Medicine,Prince of Songkla University。
文摘AIM:To investigate the clinical characteristics and treatment outcomes,including visual function and overall survival(OS)of patients with ocular adnexal diffuse large B-cell lymphoma(OA-DLBCL).METHODS:This retrospective cohort study enrolled 29 patients diagnosed with OA-DLBCL based on histopathological biopsy between 2006 and 2023.Patients were stratified into two subgroups:primary OA-DLBCL(no prior history of lymphoma)and secondary OA-DLBCL(history of DLBCL at non-ocular adnexal sites).OS was defined as the time interval from OA-DLBCL diagnosis to death from any cause.Survival analysis was performed using the Kaplan–Meier method,and prognostic factors affecting OS were identified using multivariate Cox proportional hazards regression with a stepwise selection approach.RESULTS:The cohort included 24 patients with primary OA-DLBCL(13 males,11 females;mean age:61.36±18.29y)and 5 patients with secondary OA-DLBCL(2 males,3 females;mean age:50.94±18.17y).Among the primary OA-DLBCL subgroup,12 patients(50%)presented with advanced disease(Ann Arbor stage IIIE–IV),and 16 patients(66%)were classified as T4 disease according to the tumor-node-metastasis(TNM)staging system.The mean final visual acuity was 1.72±1.10 in the primary group and 0.90±1.18 in the secondary group.The 5-year OS rate for the entire cohort was 27.7%.Multivariate analysis identified five factors significantly associated with poor survival outcomes:epiphora[adjusted hazard ratio(aHR),36.95],atherosclerotic cardiovascular disease(aHR,10.08),human immunodeficiency virus(HIV)infection(aHR,12.47),M1 stage(aHR,6.99),and secondary OA-DLBCL(aHR,6.03;all P<0.05).The median OS was 1.68y for primary OA-DLBCL and 1.12y for secondary OA-DLBCL.CONCLUSION:A substantial proportion of patients with primary OA-DLBCL present with advanced-stage disease at diagnosis.Epiphora,atherosclerotic cardiovascular disease,HIV infection,M1 stage,and secondary OA-DLBCL are independent prognostic factors for poor survival outcomes.These findings emphasize the urgent need for optimized therapeutic strategies and early screening protocols to improve the management of OA-DLBCL,particularly in developing countries.
基金financial support from the Shanghai Key Laboratory of MFree,China(Grant No.22dz2260800)the Shanghai Science and Technology Committee,China(Grant No.22JC1410300).
文摘The 2024 MRE HP Special Volume selects papers on new theoretical and experimental developments in the use of static largevolume presses(LVPs)1–3 and dynamic compression4,5 for studies under extreme high-pressure and high-temperature(HPHT)conditions.It also continues the previous year’s6 contemporary focus on superhydrides7–11 with extremely high superconducting temperatures Tc and addresses some controversial issues.12–14 In addition,it explores unconventional pressure-induced chemistry,particularly novel chemical stoichiometry and its impact on geochemistry and cosmochemistry in the deep interiors of Earth and other planets.18–21.
基金the financial support by the Natural Science Foundation of Liaoning Province of China (Grant No. 2013020122)the National Natural Science Foundationof China (Grant No. 21076100 and 51308045)the financial support by the PetroChina Company Limited (Grant No. 10-01A-01-01-01)
文摘Through improving the aging process during synthesis of the support, γ-Al2O3 with large pore volume and high surface area was synthesized by a facile secondary reforming method. The synthesis parameters, such as the reaction temperature, the first aging temperature and the second aging temperature, were investigated. The textural properties of γ-Al2O3 were characterized by means of N2 adsorption-desorption isotherms, X-ray powder diffractometry （XRD）, scanning electron microscopy （SEM）, Fourier transform infrared （FTIR） spectroscopy and thermogravimetry （TG）. The experimental results indicated that AACH and amorphous A1OOH were the precursors of alumina, which were formed via precipitation from solutions after reaction of aluminum sulphate with ammonium hydrogen carbonate. The precursor nanocrystallites grew and re-assembled during the secondary reforming process, which resulted in an increased pore size and pore volume and a decreased bulk density. The as-synthesized γ-Al2O3 materials featured meso/macroporosity, large pore volume （2.175 cm^3/g）, high surface area （237.8 m^2/g）, and low bulk density （0.284 g/mL）.
基金Combined project of monitoring,prediction and research of China Earthquake Administration entitled "Statistical study on the earthquake cases of imminent anomaly in Sacks volume strain measurements(154201)""Special Fund for Basic Scientific Research of Institute of Earthquake Science,CEA(2012IES010202)""Research on Regional Tectonic Stability for the Dateng Gorge Water Conservancy Hub Project Site(880456)"
文摘This paper studies the imminent anomalies observed by the Sacks volume strainmeter in Erzhangying station and Tiantanghe station before 80 earthquakes with Ms≥ 7. 0 which took place from January 2011 to April 2014 all over the world. Then, preconditions for anomaly identification are put forward for complex earthquake cases. Statistical results show that volume strain observation has a better earthquake reflecting ability for earthquakes with magnitudes larger than 7. 0 and epicentral distance within 8000kin. In addition, these results also reflect that the volume strain observation can better reflect precursory anomalies of such earthquakes. Based on categorization and description of those anomalies, we divide the anomalies into three types, that is, earth tide distortion type, abrupt change type and slow earthquake type. Furthermore, the paper makes a statistical analysis of these types and preliminarily discusses their mechanical properties as well. According to research, volume strain anomaly has an indicative significance to future strong earthquakes in the world.
文摘Rheological properties of large particulate-liquid model food systems were studied by using the BMS （ball measuring system）. The model food systems were composed of alginate gel particles （-10mm） and a gelatinised starch solution with 1% w/w sodium chloride as a liquid phase. The effects of particle phase volume （Ф, 0-0.60）, particle shapes （cube, sphere, rod and disc） and starch concentrations （3% and 5% w/w starch） were investigated. The power law model was successfully applied to characterize the flow properties of each system and the consistency K and power law index n were obtained. The K increased and n decreased with increasing # for samples at all particle shapes at 3% w/w starch in the liquid phase. The particle effect on the viscosity is further analysed by means of the Krieger-Dougherty model and the maximum packing fraction #,, and the intrinsic viscosity [η] were obtained in each system. The Фm, depended on the particle shape, as expected. The [7] value depended on particle shape and was largely in the order of 4.04 （cube）, 3.28 （disc）, 2.56 （sphere） and 2.32 （rod） at 3% w/w starch. The [η] also depended on starch concentration and was 1.1 at 5%,6 w/w starch in the liquid phase with spherical particles. The present results show successful application of BMS to study the rheological properties of large particulate liquid food systems at relatively small scale experiment （-0.5 L） and also that existing models for suspension rheology are applicable for such food systems to a great extend.
文摘Correlation analysis between the hematological parameters mean corpuscular hemoglobin (MCH) and mean corpuscular volume (MCV) for thalassemia screening in large population was discussed. A total of 4920 peripheral blood samples of reproductive age persons were collected from Guangdong province of China. The hematological parameters MCH and MCV values of samples were first measured, and then the DNA analyses for thalassemia were conducted. All samples were composed by 4463 non-thalassemia and 457 thalassemia, and among 457 thalassemia samples, 311 were α-thalassemia, 133 were β-thalassemia, and 13 were α & β-thalassemia. In accordance with non-thalassemia, thalassemia, α-thalassemia, β-thalassemia, α & β-thalassemia and the entire group itself, a total of six sample groups were divided. The corresponding correlation coefficients between the measured MCH and MCV values for the six sample groups were 0.880, 0.968, 0.966, 0.962, 0.980 and 0.965 respectively. For the thalassemia carriers, highly significant correlation between MCH and MCV were observed. The fitting equations between MCH and MCV values were also obtained. The results indicated that the feasibility for thalassemia screening using MCV or MCH independently as parameter, and provided suitable strategy to select parameters and models for thalassemia screening in large population.
文摘The storage, longitudinal distribution and recruitment processes of in-stream large wood (LW) were studied comparing channel segments draining four Chilean mountain catchments with different land use. The segments were divided into relatively uniform reaches of different lengths and surveyed for LW (piece dimensions, position in the channel, orientation to flow and aggregation) and stream morphology (slope and bank full channel width and depth) characterizations. LW volume stored in the Pichun, El Toro and Vuelta de Zorra study channels are within the range informed in international researches from streams draining catchments with similar forest covers. However, the 1057 m3/ha of LW stored in Tres Arroyos is extremely high and in the same order of magnitude than the reports from old-growth forests in the Pacific Northwest of USA. The size of the area that can potentially provide wood to streams depends on the wood supply mechanisms within any catchment, and the LW stored in the study segments increases as the size of this area increases. This study aims to contribute to the knowledge on the effects of LW in mountain channels, gathering new information and expanding investigations developed in Chile since 2008. This research was carried out within the framework of Project FONDECYT 11106209.
