Objective:Pathologic complete response(pCR)following neoadjuvant therapy(NAT)for gastric cancer(GC)is rare but associated with a favorable prognosis.This study aims to reassess the optimal response population(ORP)foll...Objective:Pathologic complete response(pCR)following neoadjuvant therapy(NAT)for gastric cancer(GC)is rare but associated with a favorable prognosis.This study aims to reassess the optimal response population(ORP)following NAT by evaluating the prognostic outcomes associated with various T and N stages,utilizing multicenter data from China.Methods:Patients who underwent NAT following radical gastrectomy at 10 tertiary hospitals in China between2008 and 2021 were included.The ORP was introduced to explore the disease-free survival(DFS),overall survival(OS),recurrence patterns,and influencing factors following propensity score matching(PSM).Results:A total of 1,076 patients were enrolled in this study(median follow-up period:60 months).We defined ORP as a pCR or tumor infiltration of the mucosal or submucosal layer without lymph node metastasis(pCR or yp T1N0)after NAT.The ORP group comprised 136 patients(12.6%),while the non-ORP group comprised 940patients(87.4%).After applying a 1:4 PSM,we obtained an ORP group of 136 patients and non-ORP group of 544patients.Survival analysis demonstrated that both the 3-year OS(before PSM:89.0%vs.55.0%,P<0.001;after PSM:89.0%vs.55.4%,P<0.001)and DFS(before PSM:85.8%vs.49.7%,P<0.001;after PSM:85.8%vs.50.6%,P<0.001)were significantly superior in the ORP group compared to that in the non-ORP group.Remarkably,adjuvant chemotherapy did not impact the prognosis of patients in the ORP group(3-year OS:89.0%vs.89.7%,P=0.988;3-year DFS:84.9%vs.89.7%,P=0.700).Conclusions:This study reevaluates patients with ORP following NAT,providing a more comprehensive and accurate depiction of the potential beneficiary group and survival outcomes in patients with locally advanced GC.展开更多
Wireless sensor networks are extremely vulnerable to various security threats.The intrusion detection method based on game theory can effectively balance the detection rate and energy consumption of the system.The acc...Wireless sensor networks are extremely vulnerable to various security threats.The intrusion detection method based on game theory can effectively balance the detection rate and energy consumption of the system.The accurate analysis of the attack behavior of malicious sensor nodes can help to configure intrusion detection system,reduce unnecessary system consumption and improve detection efficiency.However,the completely rational assumption of the traditional game model will cause the established model to be inconsistent with the actual attack and defense scenario.In order to formulate a reasonable and effective intrusion detection strategy,we introduce evolutionary game theory to establish an attack evolution game model based on optimal response dynamics,and then analyze the attack behavior of malicious sensor nodes.Theoretical analysis and simulation results show that the evolution trend of attacks is closely related to the number of malicious sensors in the network and the initial state of the strategy,and the attacker can set the initial strategy so that all malicious sensor nodes will eventually launch attacks.Our work is of great significance to guide the development of defense strategies for intrusion detection systems.展开更多
The rapid urbanization underscores the urgency of efficient treatment and resource utilization of municipal sludge for environmental conservation.To address this,a novel pH-responsive dual network polyvinyl alcohol/so...The rapid urbanization underscores the urgency of efficient treatment and resource utilization of municipal sludge for environmental conservation.To address this,a novel pH-responsive dual network polyvinyl alcohol/sodium alginate sludge hydrogel was devised by integrating municipal sludge with acrylic acid monomers,ammonium persulphate initiator,N,N’-methylene bisacrylamide crosslinking agent,reinforced by polyvinyl alcohol and sodium alginate through free radical cross-linking polymerization.The hydrogel’s optimal formulation was identified by adjusting the monomer,crosslinking agent,and initiator dosage while assessing its swelling behavior across various pH environments.Results revealed excellent swelling capacity,notably exhibiting a remarkable swelling capacity of up to 7265.64% at pH 11.0,suggesting the hydrogel’s potential in environmental remediation and innovative material design.This research presents a pioneering approach to harnessing municipal sludge and developing intelligent hydrogels,fostering sustainable resource management.展开更多
The time-of-use(TOU)strategy can effectively improve the energy consumption mode of customers,reduce the peak-valley difference of load curve,and optimize the allocation of energy resources.This study presents an Opti...The time-of-use(TOU)strategy can effectively improve the energy consumption mode of customers,reduce the peak-valley difference of load curve,and optimize the allocation of energy resources.This study presents an Optimal guidance mechanism of the flexible load based on strategies of direct load control and time-of-use.First,this study proposes a period partitioning model,which is based on a moving boundary technique with constraint factors,and the Dunn Validity Index(DVI)is used as the objective to solve the period partitioning.Second,a control strategy for the curtailable flexible load is investigated,and a TOU strategy is utilized for further modifying load curve.Third,a price demand response strategy for adjusting transferable load is proposed in this paper.Finally,through the case study analysis of typical daily flexible load curve,the efficiency and correctness of the proposed method and model are validated and proved.展开更多
【Objective】To optimize the steam explosion process condition for extracting polysaccharides from Pseudostellaria heterophylla.【Method】The effects of steam pressure,pressure-maintaining time and material moisture c...【Objective】To optimize the steam explosion process condition for extracting polysaccharides from Pseudostellaria heterophylla.【Method】The effects of steam pressure,pressure-maintaining time and material moisture content on the extraction of polysaccharides from Pseudostellaria heterophylla were studied by response surface methodology based on Box-Behnken design.【Result】The findings showed that each factor could significantly affect the test index,and the optimum condition was as follows:steam pressure 1.50 Mpa,pressuremaintaining time 46 s and material moisture content 46%.Under this condition,the verified experimental value of polysaccharides from Pseudostellaria heterophylla was 39.32%,indicating a relative standard deviation of 2.73%from the predictive value.Meanwhile,scanning electron microcopy(SEM)images showed that the surface physical structure of Pseudostellaria heterophylla was irregularly broken and cracked,which means the physical structure of Pseudostellaria heterophylla was changed and destroyed at the cellular level.【Conclusion】This experiment provides a new approach for the extraction of polysaccharides from Pseudostellaria heterophylla,as well as a reference for the resource utilization of Pseudostellaria heterophylla.展开更多
Taking refined flour,matsutake powder,and highland barley powder as main raw materials,this experiment studied the optimal formula of matsutake highland barley biscuit. Besides,single factor experiment was carried out...Taking refined flour,matsutake powder,and highland barley powder as main raw materials,this experiment studied the optimal formula of matsutake highland barley biscuit. Besides,single factor experiment was carried out for the amount of highland barley powder,white granulated sugar,and shortening. Then,the response surface optimization analysis was made on crispness and sensory score of the biscuit. The experiment indicates that taking the refined flour as the base 100 g( 100%),the formula of 20% highland barley powder,25% white granulated sugar,and 26% shortening can bake crisp biscuit with complete shape,pure flavor and high quality.展开更多
[Objectives] This study was conducted to optimize the extraction process of protocatechuic acid from Emilia sonchifolia DC. [Methods] The optimal extraction conditions were determined by single factor,response surface...[Objectives] This study was conducted to optimize the extraction process of protocatechuic acid from Emilia sonchifolia DC. [Methods] The optimal extraction conditions were determined by single factor,response surface analysis and variance analysis,and the content of protocatechuic acid was determined by HPLC. [Results] The protocatechuic acid standard curve equation was: y = 1 435 x + 8 403,R^2= 0. 999 8,indicating a good linear relationship. The optimal extraction conditions were as follows: a temperature at 80 ℃,an extraction time of 1 h,a material-to-liquid ratio at 1:10 and an ultrasonic power of 600 W,and the content of protocatechuic acid extracted was 1. 93 mg/g. The method showed a RSD of 0. 41%,less than 2%,and the detection limit was 0. 0000047261 g/ml.The experimental sample X1 was the low-level 0. 1 mg/ml standard solution,which showed recovery of protocatechuic acid between 100.8% and 105.2%,with a RSD of 0. 013%;and the sample X2 was the high-level 1. 0 mg/ml standard solution,which exhibited recovery between 100. 6% and 102. 2%,with a RSD of 0.076%. Thus,the recovery was high,and the requirements of the performance index were met. [Conclusions] The detection method is stable and reliable and can produce satisfactory results.展开更多
The colloidal properties of biogenic elemental sulfur（S^0）cause solid–liquid separation problems,such as poor settling and membrane fouling.In this study,the separation of S^0 from bulk liquids was performed using ...The colloidal properties of biogenic elemental sulfur（S^0）cause solid–liquid separation problems,such as poor settling and membrane fouling.In this study,the separation of S^0 from bulk liquids was performed using flocculation.Polyaluminum chloride（PAC）,polyacrylamide（PAM）and microbial flocculant（MBF）were compared to investigate their abilities to flocculate S^0 produced during the treatment of sulfate-containing wastewater.A novel approach with response surface methodology（RSM）was employed to evaluate the effects and interactions of flocculant dose,pH and stirring intensity,on the treatment efficiency in terms of the S^0 flocculation and the supernatant turbidity removal.The dose optimization results indicated that the S^0 flocculation efficiency decreased in the following order PAC〉MBF〉PAM.Optimum S^0 flocculation conditions were observed at pH 4.73,a stirring speed of 129 r/min and a flocculant dose of 2.42 mg PAC/mg S.During optimum flocculation conditions,the S^0f locculation rate reached 97.53%.Confirmation experiments demonstrated that employing PAC for S^0 flocculation is feasible and RSM is an efficient approach for optimizing the process of S^0 flocculation.The results provide basic parameters and conditions for recovering sulfur during the treatment of sulfate-laden wastewaters.展开更多
Estimation of lateral displacement and acceleration responses is essential to assess safety and serviceability of high-rise buildings under dynamic loadings including earthquake excitations. However, the measurement i...Estimation of lateral displacement and acceleration responses is essential to assess safety and serviceability of high-rise buildings under dynamic loadings including earthquake excitations. However, the measurement information from the limited number of sensors installed in a building structure is often insufficient for the complete structural performance assessment. An integrated multi-type sensor placement and response reconstruction method has thus been proposed by the authors to tackle this problem. To validate the feasibility and effectiveness of the proposed method, an experimental investigation using a cantilever beam with multi-type sensors is performed and reported in this paper. The experimental setup is first introduced. The finite element modelling and model updating of the cantilever beam are then performed. The optimal sensor placement for the best response reconstruction is determined by the proposed method based on the updated FE model of the beam. After the sensors are installed on the physical cantilever beam, a number of experiments are carried out. The responses at key locations are reconstructed and compared with the measured ones. The reconstructed responses achieve a good match with the measured ones, manifesting the feasibility and effectiveness of the proposed method. Besides, the proposed method is also examined for the cases of different excitations and unknown excitation, and the results prove the proposed method to be robust and effective. The superiority of the optimized sensor placement scheme is finally demonstrated through comparison with two other different sensor placement schemes： the accelerometer-only scheme and non-optimal sensor placement scheme. The proposed method can be applied to high-rise buildings for seismic performance assessment.展开更多
Background： Forest fertilization offers a means to increase the production of renewable resources.Nitrogen is the most common fertilizer in boreal upland forests.There is plenty of research on the effect of nitrogen ...Background： Forest fertilization offers a means to increase the production of renewable resources.Nitrogen is the most common fertilizer in boreal upland forests.There is plenty of research on the effect of nitrogen fertilization on volume growth, but less research on the optimal timing of fertilization and optimal management of fertilized stands.Methods： This study used simulation and optimization to analyze the profitability of fertilization, optimal management of fertilized stands and the effects of fertilization on cash flows and timber yields.The management of 100 stands representing the most common growing sites of Scots pine and Norway spruce was optimized.Results： Fertilization improved profitability in most of the analyzed stands.Profitability improved most in spruce stands growing on mesic site.Improving stem quality increased the economic benefit of fertilization.The timber yields of medium-aged conifer stands can be increased by almost 1 m^3·ha^（-1）·a^（-1）（15%） in sub-xeric pine and mesic spruce sites and about 0.5 m^3·ha^（-1）·a^（-1）（5%） in mesic pine and herb-rich spruce sites when the recommended nitrogen dose（150kg·ha^（-1）） is applied once in 30 years.Conclusions： Nitrogen fertilization of boreal conifer forest should be used mainly in spruce-dominated stands growing on medium sites.The gains are the highest in stands where the mean tree diameter is 16–20 cm and stand basal area is 14–20 m^2·ha^（-1）.展开更多
Atrazine, a widely used herbicide, is increasing the agricultural production effectively, while also causing great environmental concern. Efficient atrazine-degrading bacterium is necessary to removal atrazine rapidly...Atrazine, a widely used herbicide, is increasing the agricultural production effectively, while also causing great environmental concern. Efficient atrazine-degrading bacterium is necessary to removal atrazine rapidly to keep a safe environment. In the present study, a new atrazine-degrading strain ZXY-1, identified as Pseudomonas, was isolated. This new isolated strain has a strong ability to biodegrade atrazine with a high efficiency of 9.09 mg/L/hr.Temperature, p H, inoculum size and initial atrazine concentration were examined to further optimize the degradation of atrazine, and the synthetic effect of these factors were investigated by the response surface methodology. With a high quadratic polynomial mathematical model（R^2= 0.9821） being obtained, the highest biodegradation efficiency of 19.03 mg/L/hr was reached compared to previous reports under the optimal conditions（30.71°C, pH 7.14, 4.23%（V/V） inoculum size and 157.1 mg/L initial atrazine concentration）.Overall, this study provided an efficient bacterium and approach that could be potentially useful for the bioremediation of wastewater containing atrazine.展开更多
The China Infectious Disease Automated-alert and Response System（CIDARS） was successfully implemented and became operational nationwide in 2008. The CIDARS plays an important role in and has been integrated into the...The China Infectious Disease Automated-alert and Response System（CIDARS） was successfully implemented and became operational nationwide in 2008. The CIDARS plays an important role in and has been integrated into the routine outbreak monitoring efforts of the Center for Disease Control（CDC） at all levels in China. In the CIDARS, thresholds are determined using the ？Mean＋2SD？ in the early stage which have limitations. This study compared the performance of optimized thresholds defined using the ？Mean ＋2SD？ method to the performance of 5 novel algorithms to select optimal ？Outbreak Gold Standard（OGS）？ and corresponding thresholds for outbreak detection. Data for infectious disease were organized by calendar week and year. The ？Mean＋2 SD？, C1, C2, moving average（MA）, seasonal model（SM）, and cumulative sum（CUSUM） algorithms were applied. Outbreak signals for the predicted value（Px） were calculated using a percentile-based moving window. When the outbreak signals generated by an algorithm were in line with a Px generated outbreak signal for each week, this Px was then defined as the optimized threshold for that algorithm. In this study, six infectious diseases were selected and classified into TYPE A（chickenpox and mumps）, TYPE B（influenza and rubella） and TYPE C [hand foot and mouth disease（HFMD） and scarlet fever]. Optimized thresholds for chickenpox（P_（55））, mumps（P_（50））, influenza（P_（40）, P_（55）, and P_（75））, rubella（P_（45） and P_（75））, HFMD（P_（65） and P_（70））, and scarlet fever（P_（75） and P_（80）） were identified. The C1, C2, CUSUM, SM, and MA algorithms were appropriate for TYPE A. All 6 algorithms were appropriate for TYPE B. C1 and CUSUM algorithms were appropriate for TYPE C. It is critical to incorporate more flexible algorithms as OGS into the CIDRAS and to identify the proper OGS and corresponding recommended optimized threshold by different infectious disease types.展开更多
In this paper,the residue from bamboo factory has been used to design photo-Fenton catalyst,which has the advantages of low cost and magnetic recycling.The photo-Fenton catalytic performance of the biocarbon-based cat...In this paper,the residue from bamboo factory has been used to design photo-Fenton catalyst,which has the advantages of low cost and magnetic recycling.The photo-Fenton catalytic performance of the biocarbon-based catalyst was excellent and its optimal preparation process was also explored by response surface methodology.First,bamboo-carbon fiber was selected as the photo-Fenton catalyst carrier.Subsequently,the surface of the car-bon fiber was modified,with which dopamine,nano-Fe_(3)O_(4) and nano-TiO_(2) were successively loaded by hydro-thermal method.After the single factor tests,four factors including dopamine concentration,ferric chloride mass,P25 titanium dioxide mass and liquid-solid ratio were selected as the characteristic values.The degradation efficiency of photo-Fenton catalyst to methylene blue(MB)solution was treated as the response value.After the analysis of the response surface optimization,it was shown that the significance sequence of the selected 4 factors in terms of the MB degradation efficiency was arranged as follows:dopamine concentration>liquid-solid ratio>P25 titanium dioxide quality>ferric chloride quality.The optimal process parameters of fiber-carbon catalyst were affirmed as follows:the 1.7 mg/mL concentration of dopamine,the 1.2 g mass of ferric chloride,the 0.2 g mass of P25 titanium dioxide and the liquid-solid ratio of 170 mL/g.The experiment-measured average MB degra-dation efficiency performed by the optimized catalyst was 99.3%,which was nearly similar to the model-predicted value of 98.9%.It showed that the prediction model and response surface model were accurate and reliable.The results from response surface optimization could provide a good reference to design bamboo-based Fenton-like catalyst with excellent catalytic performance.展开更多
[Objectives]The ultrasound-assisted aqueous two-phase extraction of sweet potato leaf polysaccharides was studied.[Methods]With the yield of sweet potato leaf polysaccharides as the index,the aqueous two-phase extract...[Objectives]The ultrasound-assisted aqueous two-phase extraction of sweet potato leaf polysaccharides was studied.[Methods]With the yield of sweet potato leaf polysaccharides as the index,the aqueous two-phase extraction system was determined,and the optimal extraction conditions were optimized by single-factor experiments and response surface methodology.[Results]The optimal parameters were ethanol concentration 25.68%,liquid-to-material ratio 55.83,and ultrasonic treatment time 38.33 min.Under these conditions,the yield of sweet potato leaf polysaccharides could reach 20.646 mg/g.[Conclusions]The ethanol/ammonium sulfate aqueous system is a rapid and efficient method for extracting sweet potato leaf polysaccharides,which is of great significance for the application of sweet potato leaf extract as a natural food additive.展开更多
Background:In the visual system,one of the most explored neural behaviors is the response of cells to changes in visual contrast.This neural response to visual contrast,also known as the contrast response function(CRF...Background:In the visual system,one of the most explored neural behaviors is the response of cells to changes in visual contrast.This neural response to visual contrast,also known as the contrast response function(CRF),can be fitted with the Naka-Rushton equation(NRE).Assessing the CRF of many neurons at the same time is critical to establishing functional visual properties.However,maximizing the performance of neurons to fit the NRE,while minimizing their time acquisitions is a challenge.We present a method to accurately obtain reliable NRE fits from experimental data,that ensure a reasonable time of record acquisition.Methods:We simulated CRF of cortical neurons with a toy model based on the response of Poisson spike trains to varied levels of contrasts.We first tested whether mean values or the whole set of contrast responses fit better the NRE.Then,we analyzed what were the boundaries to optimize the fit of the NRE,and after we explore the consequences of fitting the NRE with single-or multi-units.With these outcomes,we varied experimental parameters such as the number of trials,number of input contrasts and length of time acquisition to calculate the errors of fitting CRFs.Those data sets that maximize the CRF fit but minimize the time of recording were selected.The selected data set was then evaluated in visual cortical neurons of anesthetized cats from areas 17,18 and 21a.Results:First,we found that is always better to fit the NRE with mean values rather than the whole set of points.Then,we noticed that either removing or imposing loose boundaries to the CRF parameters lead to an increase in the performance of the NRE fit.Afterward,we found that single units(SU)or assume multi-unit formed of several SUs(>30)adjusted considerably better the NRE fit.Finally,the experiments showed that specific sets of patterns(number of trials,number of input contrasts and length of time acquisition)satisfied our two constraints:minimize the error of the NRE fit while maximizing the acquisition time of recording.The most characteristic pattern was the one with 6 points,15 repetitions and 1 second of duration.However,cortical areas varied in the representation of the patterns.Conclusions:Theoretical simulations of many different sets of patterns and their following experimental validation suggest strongly that a particular set of patterns can satisfy the imposed constraints.With this approach,we provided a tool that allows an optimal design of stimuli to assess the CRF of large neuronal populations and guarantees the finest fit for each unit analyzed.展开更多
In order to shorten the design period, the paper describes a new optimization strategy for computationally expensive design optimization of turbomachinery, combined with design of experiment (DOE), response surface mo...In order to shorten the design period, the paper describes a new optimization strategy for computationally expensive design optimization of turbomachinery, combined with design of experiment (DOE), response surface models (RSM), genetic algorithm (GA) and a 3-D Navier-Stokes solver(Numeca Fine). Data points for response evaluations were selected by improved distributed hypercube sampling (IHS) and the 3-D Navier-Stokes analysis was carried out at these sample points. The quadratic response surface model was used to approximate the relationships between the design variables and flow parameters. To maximize the adiabatic efficiency, the genetic algorithm was applied to the response surface model to perform global optimization to achieve the optimum design of NASA Stage 35. An optimum leading edge line was found, which produced a new 3-D rotor blade combined with sweep and lean, and a new stator one with skew. It is concluded that the proposed strategy can provide a reliable method for design optimization of turbomachinery blades at reasonable computing cost.展开更多
[Objectives]To explore the saponins resources in fibrous roots of Pseudostellaria heterophylla and optimize the SEP technology for extracting saponins.[Methods]Saponins contents in fibrous roots and root tubers of P.h...[Objectives]To explore the saponins resources in fibrous roots of Pseudostellaria heterophylla and optimize the SEP technology for extracting saponins.[Methods]Saponins contents in fibrous roots and root tubers of P.heterophylla were compared;with the fibrous roots as host materials,this experiment applied Box-Behnken design to analyze the influence of steam pressure,maintenance pressure time,moisture content of host materials on the content of saponins extracts.[Results]Saponins content was higher in fibrous roots than in tuberous roots of P.heterophylla;the response surface optimization showed that SEP(steam explosion pretreatment)promoted the contents of saponins and extracts in fibrous roots,and the optimal extracting conditions were stream pressure 1.50 Mpa,maintenance pressure time 54 s,and moisture content of host materials 30%.Under this extracting conditions,the verification value of saponins content experiment was 0.441%,36.53%higher than the untreated control group.[Conclusions]This research offered a new method of exploring saponins resources from fibrous roots of P.heterophylla,and provided a reference for developing new medicinal parts of P.heterophylla.展开更多
The optimized production of a novel bioflocculant M-C11 produced by Klebsiella sp. and its application in sludge dewatering were investigated. The optimal medium carbon source,nitrogen source, metal ion, initial pH an...The optimized production of a novel bioflocculant M-C11 produced by Klebsiella sp. and its application in sludge dewatering were investigated. The optimal medium carbon source,nitrogen source, metal ion, initial pH and culture temperature for the bioflocculant production were glucose, NaNO3, MgSO4, and pH 7.0 and 25°C, respectively. A compositional analysis indicated that the purified M-C11 consisted of 91.2% sugar, 4.6% protein and 3.9% nucleic acids（m/m）. A Fourier transform infrared spectrum confirmed the presence of carboxyl, hydroxyl,methoxyl and amino groups. The microbial flocculant exhibited excellent pH and thermal stability in a kaolin suspension over a pH range of 4.0 to 8.0 and a temperature range of 20 to 60°C.The optimum bioflocculating activity was observed as 92.37% for 2.56 mL M-C11 and 0.37 g/L CaCl2 dosages using response surface methodology. The sludge resistance in filtration（SRF）decreased from 11.6 × 1012 to 4.7 × 1012m/kg, which indicated that the sludge dewaterability was remarkably enhanced by the bioflocculant conditioning. The sludge dewatering performance conditioned by M-C11 was more efficient than that of inorganic flocculating reagents,such as aluminum sulfate and polymeric aluminum chloride. The bioflocculant has advantages over traditional sludge conditioners due to its lower cost, benign biodegradability and negligible secondary pollution. In addition, the bioflocculant was favorably adapted to the specific sludge pH and salinity.展开更多
In order to design the press bend forming path of aircraft integral panels,a novel optimization method was proposed, which integrates FEM equivalent model based on previous study,the artificial neural network response...In order to design the press bend forming path of aircraft integral panels,a novel optimization method was proposed, which integrates FEM equivalent model based on previous study,the artificial neural network response surface,and the genetic algorithm.First,a multi-step press bend forming FEM equivalent model was established,with which the FEM experiments designed with Taguchi method were performed.Then,the BP neural network response surface was developed with the sample data from the FEM experiments.Furthermore,genetic algorithm was applied with the neural network response surface as the objective function. Finally,verification was carried out on a simple curvature grid-type stiffened panel.The forming error of the panel formed with the optimal path is only 0.098 39 and the calculating efficiency has been improved by 77%.Therefore,this novel optimization method is quite efficient and indispensable for the press bend forming path designing.展开更多
Response surface (RSM) methodology based on a three-level three-factor Box-Behnkendesign of experiment was used to optimize the exopolysaccharide content (EPC) and themycelium biomass in submerged cultivation by Clito...Response surface (RSM) methodology based on a three-level three-factor Box-Behnkendesign of experiment was used to optimize the exopolysaccharide content (EPC) and themycelium biomass in submerged cultivation by Clitocybe sp. AS 5.112. The criticalfactors selected for the investigation were cultivation temperature, time and volume ofmedium, based on the results of previous Plackett-Burman design. By analyzing theresponse surface plots, the optimum ranges of cultivation temperature, time and mediumvolume for obtaining over 1 253.00gmL-1 of EPC lie in 24.325.8℃, 9.710.2d and 76.090.0mL, respectively. While for obtaining over 8.32 mg mL-1 of dry cell weight (DCW), theabove variables would be in the range of 23.824.8℃, 9.610.3d and 71.098.0mL,respectively. By solving the inverse matrix from the quadratic regression equations, theoptimal conditions to gain 1 265.45gmL-1 of EPC were 25.0℃, 9.9d and 83.4mL, to gain8.50mg mL-1 of DCW were 24.4℃, 9.9d and 87.1mL. In order to obtain the maximum yield ofEPC and DCW at the same time, the above conditions would be 24.5℃, 9.9d and 84.7mL,respectively, in this situation, the maximum predicted EPC and DCW were 1 261.60gmL-1and 8.47mgmL-1, respectively. The experimental data under various conditions have validatedthe theoretical values.展开更多
基金supported by the construction funds for“high-level hospitals and clinical specialties”of Fujian Province(No.[2021]76)。
文摘Objective:Pathologic complete response(pCR)following neoadjuvant therapy(NAT)for gastric cancer(GC)is rare but associated with a favorable prognosis.This study aims to reassess the optimal response population(ORP)following NAT by evaluating the prognostic outcomes associated with various T and N stages,utilizing multicenter data from China.Methods:Patients who underwent NAT following radical gastrectomy at 10 tertiary hospitals in China between2008 and 2021 were included.The ORP was introduced to explore the disease-free survival(DFS),overall survival(OS),recurrence patterns,and influencing factors following propensity score matching(PSM).Results:A total of 1,076 patients were enrolled in this study(median follow-up period:60 months).We defined ORP as a pCR or tumor infiltration of the mucosal or submucosal layer without lymph node metastasis(pCR or yp T1N0)after NAT.The ORP group comprised 136 patients(12.6%),while the non-ORP group comprised 940patients(87.4%).After applying a 1:4 PSM,we obtained an ORP group of 136 patients and non-ORP group of 544patients.Survival analysis demonstrated that both the 3-year OS(before PSM:89.0%vs.55.0%,P<0.001;after PSM:89.0%vs.55.4%,P<0.001)and DFS(before PSM:85.8%vs.49.7%,P<0.001;after PSM:85.8%vs.50.6%,P<0.001)were significantly superior in the ORP group compared to that in the non-ORP group.Remarkably,adjuvant chemotherapy did not impact the prognosis of patients in the ORP group(3-year OS:89.0%vs.89.7%,P=0.988;3-year DFS:84.9%vs.89.7%,P=0.700).Conclusions:This study reevaluates patients with ORP following NAT,providing a more comprehensive and accurate depiction of the potential beneficiary group and survival outcomes in patients with locally advanced GC.
基金National Natural Science Foundation of China(No.61163009)。
文摘Wireless sensor networks are extremely vulnerable to various security threats.The intrusion detection method based on game theory can effectively balance the detection rate and energy consumption of the system.The accurate analysis of the attack behavior of malicious sensor nodes can help to configure intrusion detection system,reduce unnecessary system consumption and improve detection efficiency.However,the completely rational assumption of the traditional game model will cause the established model to be inconsistent with the actual attack and defense scenario.In order to formulate a reasonable and effective intrusion detection strategy,we introduce evolutionary game theory to establish an attack evolution game model based on optimal response dynamics,and then analyze the attack behavior of malicious sensor nodes.Theoretical analysis and simulation results show that the evolution trend of attacks is closely related to the number of malicious sensors in the network and the initial state of the strategy,and the attacker can set the initial strategy so that all malicious sensor nodes will eventually launch attacks.Our work is of great significance to guide the development of defense strategies for intrusion detection systems.
基金the Hubei Provincial Key Scientific Research Project on Water Resources“Study on the Distribution and Characteristics of Sediment Siltation in the Key Waters of Zhanghe Reservoir(HBSLKY202302)”Wuhan Municipal Bureau of Science and Technology 2023 Knowledge and Innovation Special Project,“Research on key technology for fine traceability of total phosphorus in urban lakes in Wuhan”(No.2023020201010119)+1 种基金the National Visiting Scholar Program for Key Young Teachers of Central and Western Universities,and the Ministry of Education(19042)Science and Technology Tackling Projects in Henan Province in 2025(Research on key technology for removing microdust from the surface of photovoltaic power generation panels by spray coating with high-efficiency hydrogel coatings prepared from multi-source solid wastes).
文摘The rapid urbanization underscores the urgency of efficient treatment and resource utilization of municipal sludge for environmental conservation.To address this,a novel pH-responsive dual network polyvinyl alcohol/sodium alginate sludge hydrogel was devised by integrating municipal sludge with acrylic acid monomers,ammonium persulphate initiator,N,N’-methylene bisacrylamide crosslinking agent,reinforced by polyvinyl alcohol and sodium alginate through free radical cross-linking polymerization.The hydrogel’s optimal formulation was identified by adjusting the monomer,crosslinking agent,and initiator dosage while assessing its swelling behavior across various pH environments.Results revealed excellent swelling capacity,notably exhibiting a remarkable swelling capacity of up to 7265.64% at pH 11.0,suggesting the hydrogel’s potential in environmental remediation and innovative material design.This research presents a pioneering approach to harnessing municipal sludge and developing intelligent hydrogels,fostering sustainable resource management.
基金supported by open fund of state key laboratory of operation and control of renewable energy&storage systems(China electric power research institute)(No.NYB51202201709).
文摘The time-of-use(TOU)strategy can effectively improve the energy consumption mode of customers,reduce the peak-valley difference of load curve,and optimize the allocation of energy resources.This study presents an Optimal guidance mechanism of the flexible load based on strategies of direct load control and time-of-use.First,this study proposes a period partitioning model,which is based on a moving boundary technique with constraint factors,and the Dunn Validity Index(DVI)is used as the objective to solve the period partitioning.Second,a control strategy for the curtailable flexible load is investigated,and a TOU strategy is utilized for further modifying load curve.Third,a price demand response strategy for adjusting transferable load is proposed in this paper.Finally,through the case study analysis of typical daily flexible load curve,the efficiency and correctness of the proposed method and model are validated and proved.
文摘【Objective】To optimize the steam explosion process condition for extracting polysaccharides from Pseudostellaria heterophylla.【Method】The effects of steam pressure,pressure-maintaining time and material moisture content on the extraction of polysaccharides from Pseudostellaria heterophylla were studied by response surface methodology based on Box-Behnken design.【Result】The findings showed that each factor could significantly affect the test index,and the optimum condition was as follows:steam pressure 1.50 Mpa,pressuremaintaining time 46 s and material moisture content 46%.Under this condition,the verified experimental value of polysaccharides from Pseudostellaria heterophylla was 39.32%,indicating a relative standard deviation of 2.73%from the predictive value.Meanwhile,scanning electron microcopy(SEM)images showed that the surface physical structure of Pseudostellaria heterophylla was irregularly broken and cracked,which means the physical structure of Pseudostellaria heterophylla was changed and destroyed at the cellular level.【Conclusion】This experiment provides a new approach for the extraction of polysaccharides from Pseudostellaria heterophylla,as well as a reference for the resource utilization of Pseudostellaria heterophylla.
基金Supported by Agricultural Product Processing Technology and Product Development Project of the 13th Five-Year Plan of Tibet
文摘Taking refined flour,matsutake powder,and highland barley powder as main raw materials,this experiment studied the optimal formula of matsutake highland barley biscuit. Besides,single factor experiment was carried out for the amount of highland barley powder,white granulated sugar,and shortening. Then,the response surface optimization analysis was made on crispness and sensory score of the biscuit. The experiment indicates that taking the refined flour as the base 100 g( 100%),the formula of 20% highland barley powder,25% white granulated sugar,and 26% shortening can bake crisp biscuit with complete shape,pure flavor and high quality.
基金Supported by Basic and Applied Basic Research Plan of Hainan Province in2019 (2019RC245)Natural Science Foundation of Hainan Province in 2017(217157)。
文摘[Objectives] This study was conducted to optimize the extraction process of protocatechuic acid from Emilia sonchifolia DC. [Methods] The optimal extraction conditions were determined by single factor,response surface analysis and variance analysis,and the content of protocatechuic acid was determined by HPLC. [Results] The protocatechuic acid standard curve equation was: y = 1 435 x + 8 403,R^2= 0. 999 8,indicating a good linear relationship. The optimal extraction conditions were as follows: a temperature at 80 ℃,an extraction time of 1 h,a material-to-liquid ratio at 1:10 and an ultrasonic power of 600 W,and the content of protocatechuic acid extracted was 1. 93 mg/g. The method showed a RSD of 0. 41%,less than 2%,and the detection limit was 0. 0000047261 g/ml.The experimental sample X1 was the low-level 0. 1 mg/ml standard solution,which showed recovery of protocatechuic acid between 100.8% and 105.2%,with a RSD of 0. 013%;and the sample X2 was the high-level 1. 0 mg/ml standard solution,which exhibited recovery between 100. 6% and 102. 2%,with a RSD of 0.076%. Thus,the recovery was high,and the requirements of the performance index were met. [Conclusions] The detection method is stable and reliable and can produce satisfactory results.
基金supported by the National High-Tech Research and Development Program(863)of China(No.2011AA060904)the National Science Foundation for Distinguished Young Scholars(No.51225802)+3 种基金the Science Fund for Creative Research Groups of the National Natural Science Foundation of China(No.51121062)the National Key Technology Research and Development Program of the Ministry of Science and Technology of China(No.2010BAC67B02)the Fundamental Research Funds for Central Universities(No.AUGA5710055514)the National Natural Science Foundation of China(Nos.51176037,1308147,51308147 and 51408591)
文摘The colloidal properties of biogenic elemental sulfur（S^0）cause solid–liquid separation problems,such as poor settling and membrane fouling.In this study,the separation of S^0 from bulk liquids was performed using flocculation.Polyaluminum chloride（PAC）,polyacrylamide（PAM）and microbial flocculant（MBF）were compared to investigate their abilities to flocculate S^0 produced during the treatment of sulfate-containing wastewater.A novel approach with response surface methodology（RSM）was employed to evaluate the effects and interactions of flocculant dose,pH and stirring intensity,on the treatment efficiency in terms of the S^0 flocculation and the supernatant turbidity removal.The dose optimization results indicated that the S^0 flocculation efficiency decreased in the following order PAC〉MBF〉PAM.Optimum S^0 flocculation conditions were observed at pH 4.73,a stirring speed of 129 r/min and a flocculant dose of 2.42 mg PAC/mg S.During optimum flocculation conditions,the S^0f locculation rate reached 97.53%.Confirmation experiments demonstrated that employing PAC for S^0 flocculation is feasible and RSM is an efficient approach for optimizing the process of S^0 flocculation.The results provide basic parameters and conditions for recovering sulfur during the treatment of sulfate-laden wastewaters.
基金The Hong Kong Polytechnic University through the group project "Fundamentals of Earthquake Engineering for Hong Kong"(4-ZZCD)the collaborative research project with Beijing University of Technology(4-ZZGD)
文摘Estimation of lateral displacement and acceleration responses is essential to assess safety and serviceability of high-rise buildings under dynamic loadings including earthquake excitations. However, the measurement information from the limited number of sensors installed in a building structure is often insufficient for the complete structural performance assessment. An integrated multi-type sensor placement and response reconstruction method has thus been proposed by the authors to tackle this problem. To validate the feasibility and effectiveness of the proposed method, an experimental investigation using a cantilever beam with multi-type sensors is performed and reported in this paper. The experimental setup is first introduced. The finite element modelling and model updating of the cantilever beam are then performed. The optimal sensor placement for the best response reconstruction is determined by the proposed method based on the updated FE model of the beam. After the sensors are installed on the physical cantilever beam, a number of experiments are carried out. The responses at key locations are reconstructed and compared with the measured ones. The reconstructed responses achieve a good match with the measured ones, manifesting the feasibility and effectiveness of the proposed method. Besides, the proposed method is also examined for the cases of different excitations and unknown excitation, and the results prove the proposed method to be robust and effective. The superiority of the optimized sensor placement scheme is finally demonstrated through comparison with two other different sensor placement schemes： the accelerometer-only scheme and non-optimal sensor placement scheme. The proposed method can be applied to high-rise buildings for seismic performance assessment.
文摘Background： Forest fertilization offers a means to increase the production of renewable resources.Nitrogen is the most common fertilizer in boreal upland forests.There is plenty of research on the effect of nitrogen fertilization on volume growth, but less research on the optimal timing of fertilization and optimal management of fertilized stands.Methods： This study used simulation and optimization to analyze the profitability of fertilization, optimal management of fertilized stands and the effects of fertilization on cash flows and timber yields.The management of 100 stands representing the most common growing sites of Scots pine and Norway spruce was optimized.Results： Fertilization improved profitability in most of the analyzed stands.Profitability improved most in spruce stands growing on mesic site.Improving stem quality increased the economic benefit of fertilization.The timber yields of medium-aged conifer stands can be increased by almost 1 m^3·ha^（-1）·a^（-1）（15%） in sub-xeric pine and mesic spruce sites and about 0.5 m^3·ha^（-1）·a^（-1）（5%） in mesic pine and herb-rich spruce sites when the recommended nitrogen dose（150kg·ha^（-1）） is applied once in 30 years.Conclusions： Nitrogen fertilization of boreal conifer forest should be used mainly in spruce-dominated stands growing on medium sites.The gains are the highest in stands where the mean tree diameter is 16–20 cm and stand basal area is 14–20 m^2·ha^（-1）.
基金supported by the Major Science and Technology Program for Water Pollution Control and Treatment(No.2012ZX07212001)the National Natural Science Foundation of China(No.31570505)the State Key Laboratory of Urban Water Resource and Environment,Harbin Institute of Technology(No.2014TS05)
文摘Atrazine, a widely used herbicide, is increasing the agricultural production effectively, while also causing great environmental concern. Efficient atrazine-degrading bacterium is necessary to removal atrazine rapidly to keep a safe environment. In the present study, a new atrazine-degrading strain ZXY-1, identified as Pseudomonas, was isolated. This new isolated strain has a strong ability to biodegrade atrazine with a high efficiency of 9.09 mg/L/hr.Temperature, p H, inoculum size and initial atrazine concentration were examined to further optimize the degradation of atrazine, and the synthetic effect of these factors were investigated by the response surface methodology. With a high quadratic polynomial mathematical model（R^2= 0.9821） being obtained, the highest biodegradation efficiency of 19.03 mg/L/hr was reached compared to previous reports under the optimal conditions（30.71°C, pH 7.14, 4.23%（V/V） inoculum size and 157.1 mg/L initial atrazine concentration）.Overall, this study provided an efficient bacterium and approach that could be potentially useful for the bioremediation of wastewater containing atrazine.
基金supported by the Key Laboratory of Public Health Safety of the Ministry of Education,Fudan University,China(No.GW2015-1)
文摘The China Infectious Disease Automated-alert and Response System（CIDARS） was successfully implemented and became operational nationwide in 2008. The CIDARS plays an important role in and has been integrated into the routine outbreak monitoring efforts of the Center for Disease Control（CDC） at all levels in China. In the CIDARS, thresholds are determined using the ？Mean＋2SD？ in the early stage which have limitations. This study compared the performance of optimized thresholds defined using the ？Mean ＋2SD？ method to the performance of 5 novel algorithms to select optimal ？Outbreak Gold Standard（OGS）？ and corresponding thresholds for outbreak detection. Data for infectious disease were organized by calendar week and year. The ？Mean＋2 SD？, C1, C2, moving average（MA）, seasonal model（SM）, and cumulative sum（CUSUM） algorithms were applied. Outbreak signals for the predicted value（Px） were calculated using a percentile-based moving window. When the outbreak signals generated by an algorithm were in line with a Px generated outbreak signal for each week, this Px was then defined as the optimized threshold for that algorithm. In this study, six infectious diseases were selected and classified into TYPE A（chickenpox and mumps）, TYPE B（influenza and rubella） and TYPE C [hand foot and mouth disease（HFMD） and scarlet fever]. Optimized thresholds for chickenpox（P_（55））, mumps（P_（50））, influenza（P_（40）, P_（55）, and P_（75））, rubella（P_（45） and P_（75））, HFMD（P_（65） and P_（70））, and scarlet fever（P_（75） and P_（80）） were identified. The C1, C2, CUSUM, SM, and MA algorithms were appropriate for TYPE A. All 6 algorithms were appropriate for TYPE B. C1 and CUSUM algorithms were appropriate for TYPE C. It is critical to incorporate more flexible algorithms as OGS into the CIDRAS and to identify the proper OGS and corresponding recommended optimized threshold by different infectious disease types.
基金funding from Hunan Provincial Key Research and Development Program(2020WK2018)Hunan Provincial Forestry Technological Innovation Funds(XLK202107-3)+2 种基金Scientific Research Project of Hunan Education Department(19A505,21B0242)National Natural Science Foundation of China(No.21908251)Hunan Provincial Natural Science Foundation of China(No.2020JJ2058).
文摘In this paper,the residue from bamboo factory has been used to design photo-Fenton catalyst,which has the advantages of low cost and magnetic recycling.The photo-Fenton catalytic performance of the biocarbon-based catalyst was excellent and its optimal preparation process was also explored by response surface methodology.First,bamboo-carbon fiber was selected as the photo-Fenton catalyst carrier.Subsequently,the surface of the car-bon fiber was modified,with which dopamine,nano-Fe_(3)O_(4) and nano-TiO_(2) were successively loaded by hydro-thermal method.After the single factor tests,four factors including dopamine concentration,ferric chloride mass,P25 titanium dioxide mass and liquid-solid ratio were selected as the characteristic values.The degradation efficiency of photo-Fenton catalyst to methylene blue(MB)solution was treated as the response value.After the analysis of the response surface optimization,it was shown that the significance sequence of the selected 4 factors in terms of the MB degradation efficiency was arranged as follows:dopamine concentration>liquid-solid ratio>P25 titanium dioxide quality>ferric chloride quality.The optimal process parameters of fiber-carbon catalyst were affirmed as follows:the 1.7 mg/mL concentration of dopamine,the 1.2 g mass of ferric chloride,the 0.2 g mass of P25 titanium dioxide and the liquid-solid ratio of 170 mL/g.The experiment-measured average MB degra-dation efficiency performed by the optimized catalyst was 99.3%,which was nearly similar to the model-predicted value of 98.9%.It showed that the prediction model and response surface model were accurate and reliable.The results from response surface optimization could provide a good reference to design bamboo-based Fenton-like catalyst with excellent catalytic performance.
文摘[Objectives]The ultrasound-assisted aqueous two-phase extraction of sweet potato leaf polysaccharides was studied.[Methods]With the yield of sweet potato leaf polysaccharides as the index,the aqueous two-phase extraction system was determined,and the optimal extraction conditions were optimized by single-factor experiments and response surface methodology.[Results]The optimal parameters were ethanol concentration 25.68%,liquid-to-material ratio 55.83,and ultrasonic treatment time 38.33 min.Under these conditions,the yield of sweet potato leaf polysaccharides could reach 20.646 mg/g.[Conclusions]The ethanol/ammonium sulfate aqueous system is a rapid and efficient method for extracting sweet potato leaf polysaccharides,which is of great significance for the application of sweet potato leaf extract as a natural food additive.
文摘Background:In the visual system,one of the most explored neural behaviors is the response of cells to changes in visual contrast.This neural response to visual contrast,also known as the contrast response function(CRF),can be fitted with the Naka-Rushton equation(NRE).Assessing the CRF of many neurons at the same time is critical to establishing functional visual properties.However,maximizing the performance of neurons to fit the NRE,while minimizing their time acquisitions is a challenge.We present a method to accurately obtain reliable NRE fits from experimental data,that ensure a reasonable time of record acquisition.Methods:We simulated CRF of cortical neurons with a toy model based on the response of Poisson spike trains to varied levels of contrasts.We first tested whether mean values or the whole set of contrast responses fit better the NRE.Then,we analyzed what were the boundaries to optimize the fit of the NRE,and after we explore the consequences of fitting the NRE with single-or multi-units.With these outcomes,we varied experimental parameters such as the number of trials,number of input contrasts and length of time acquisition to calculate the errors of fitting CRFs.Those data sets that maximize the CRF fit but minimize the time of recording were selected.The selected data set was then evaluated in visual cortical neurons of anesthetized cats from areas 17,18 and 21a.Results:First,we found that is always better to fit the NRE with mean values rather than the whole set of points.Then,we noticed that either removing or imposing loose boundaries to the CRF parameters lead to an increase in the performance of the NRE fit.Afterward,we found that single units(SU)or assume multi-unit formed of several SUs(>30)adjusted considerably better the NRE fit.Finally,the experiments showed that specific sets of patterns(number of trials,number of input contrasts and length of time acquisition)satisfied our two constraints:minimize the error of the NRE fit while maximizing the acquisition time of recording.The most characteristic pattern was the one with 6 points,15 repetitions and 1 second of duration.However,cortical areas varied in the representation of the patterns.Conclusions:Theoretical simulations of many different sets of patterns and their following experimental validation suggest strongly that a particular set of patterns can satisfy the imposed constraints.With this approach,we provided a tool that allows an optimal design of stimuli to assess the CRF of large neuronal populations and guarantees the finest fit for each unit analyzed.
文摘In order to shorten the design period, the paper describes a new optimization strategy for computationally expensive design optimization of turbomachinery, combined with design of experiment (DOE), response surface models (RSM), genetic algorithm (GA) and a 3-D Navier-Stokes solver(Numeca Fine). Data points for response evaluations were selected by improved distributed hypercube sampling (IHS) and the 3-D Navier-Stokes analysis was carried out at these sample points. The quadratic response surface model was used to approximate the relationships between the design variables and flow parameters. To maximize the adiabatic efficiency, the genetic algorithm was applied to the response surface model to perform global optimization to achieve the optimum design of NASA Stage 35. An optimum leading edge line was found, which produced a new 3-D rotor blade combined with sweep and lean, and a new stator one with skew. It is concluded that the proposed strategy can provide a reliable method for design optimization of turbomachinery blades at reasonable computing cost.
基金Instructive Project of Fujian Provincial Science and Technology Plan(2019Y6005)Innovation Funding Program of Fujian Provincial Department of Science and Technology。
文摘[Objectives]To explore the saponins resources in fibrous roots of Pseudostellaria heterophylla and optimize the SEP technology for extracting saponins.[Methods]Saponins contents in fibrous roots and root tubers of P.heterophylla were compared;with the fibrous roots as host materials,this experiment applied Box-Behnken design to analyze the influence of steam pressure,maintenance pressure time,moisture content of host materials on the content of saponins extracts.[Results]Saponins content was higher in fibrous roots than in tuberous roots of P.heterophylla;the response surface optimization showed that SEP(steam explosion pretreatment)promoted the contents of saponins and extracts in fibrous roots,and the optimal extracting conditions were stream pressure 1.50 Mpa,maintenance pressure time 54 s,and moisture content of host materials 30%.Under this extracting conditions,the verification value of saponins content experiment was 0.441%,36.53%higher than the untreated control group.[Conclusions]This research offered a new method of exploring saponins resources from fibrous roots of P.heterophylla,and provided a reference for developing new medicinal parts of P.heterophylla.
基金supported by the National Water Pollution Control Program (No. 2008ZX07313-002)
文摘The optimized production of a novel bioflocculant M-C11 produced by Klebsiella sp. and its application in sludge dewatering were investigated. The optimal medium carbon source,nitrogen source, metal ion, initial pH and culture temperature for the bioflocculant production were glucose, NaNO3, MgSO4, and pH 7.0 and 25°C, respectively. A compositional analysis indicated that the purified M-C11 consisted of 91.2% sugar, 4.6% protein and 3.9% nucleic acids（m/m）. A Fourier transform infrared spectrum confirmed the presence of carboxyl, hydroxyl,methoxyl and amino groups. The microbial flocculant exhibited excellent pH and thermal stability in a kaolin suspension over a pH range of 4.0 to 8.0 and a temperature range of 20 to 60°C.The optimum bioflocculating activity was observed as 92.37% for 2.56 mL M-C11 and 0.37 g/L CaCl2 dosages using response surface methodology. The sludge resistance in filtration（SRF）decreased from 11.6 × 1012 to 4.7 × 1012m/kg, which indicated that the sludge dewaterability was remarkably enhanced by the bioflocculant conditioning. The sludge dewatering performance conditioned by M-C11 was more efficient than that of inorganic flocculating reagents,such as aluminum sulfate and polymeric aluminum chloride. The bioflocculant has advantages over traditional sludge conditioners due to its lower cost, benign biodegradability and negligible secondary pollution. In addition, the bioflocculant was favorably adapted to the specific sludge pH and salinity.
基金Project(20091102110021)supported by the Specialized Research Fund for the Doctoral Program of Higher Education of China
文摘In order to design the press bend forming path of aircraft integral panels,a novel optimization method was proposed, which integrates FEM equivalent model based on previous study,the artificial neural network response surface,and the genetic algorithm.First,a multi-step press bend forming FEM equivalent model was established,with which the FEM experiments designed with Taguchi method were performed.Then,the BP neural network response surface was developed with the sample data from the FEM experiments.Furthermore,genetic algorithm was applied with the neural network response surface as the objective function. Finally,verification was carried out on a simple curvature grid-type stiffened panel.The forming error of the panel formed with the optimal path is only 0.098 39 and the calculating efficiency has been improved by 77%.Therefore,this novel optimization method is quite efficient and indispensable for the press bend forming path designing.
文摘Response surface (RSM) methodology based on a three-level three-factor Box-Behnkendesign of experiment was used to optimize the exopolysaccharide content (EPC) and themycelium biomass in submerged cultivation by Clitocybe sp. AS 5.112. The criticalfactors selected for the investigation were cultivation temperature, time and volume ofmedium, based on the results of previous Plackett-Burman design. By analyzing theresponse surface plots, the optimum ranges of cultivation temperature, time and mediumvolume for obtaining over 1 253.00gmL-1 of EPC lie in 24.325.8℃, 9.710.2d and 76.090.0mL, respectively. While for obtaining over 8.32 mg mL-1 of dry cell weight (DCW), theabove variables would be in the range of 23.824.8℃, 9.610.3d and 71.098.0mL,respectively. By solving the inverse matrix from the quadratic regression equations, theoptimal conditions to gain 1 265.45gmL-1 of EPC were 25.0℃, 9.9d and 83.4mL, to gain8.50mg mL-1 of DCW were 24.4℃, 9.9d and 87.1mL. In order to obtain the maximum yield ofEPC and DCW at the same time, the above conditions would be 24.5℃, 9.9d and 84.7mL,respectively, in this situation, the maximum predicted EPC and DCW were 1 261.60gmL-1and 8.47mgmL-1, respectively. The experimental data under various conditions have validatedthe theoretical values.
