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Study on Generation Cost Prediction Based on Coal Quality and Generating Unit Performance 被引量:6
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作者 ZHONG Wei LIU Chenggang ZHOU Yonggang WU Yanling ZHOU Yi LI Pei 《中国电机工程学报》 EI CSCD 北大核心 2013年第11期I0004-I0004,6,共1页
燃料变化条件下发电成本的预测是火电厂普遍关心的重要课题。分析了影响机组性能及发电电量成本的各种煤质指标,重点研究了基于结构参数及燃烧传热机理的锅炉稳态热力性能分析计算方法,讨论了制粉系统、风机、脱硫和脱硝装置性能随燃... 燃料变化条件下发电成本的预测是火电厂普遍关心的重要课题。分析了影响机组性能及发电电量成本的各种煤质指标,重点研究了基于结构参数及燃烧传热机理的锅炉稳态热力性能分析计算方法,讨论了制粉系统、风机、脱硫和脱硝装置性能随燃料等运行条件的变化关系,最终提出了基于煤质和机组性能分析计算的发电电量成本预测模型并研发了“煤炭选配与机组发电成本预测系统”。该系统在我国某600MW火电厂的实际应用经验表明:提出的电量成本分析预测模型合理,研发的软件系统有助于辅助火电厂的选煤和购煤决策,优化动力配煤方案,从而提高火电厂的运行经济性。 展开更多
关键词 成本预测 发电成本 机组性能 市场化改革 煤质 火电厂 电力 燃料
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The Two-Constant Cost Model and the Estimation of the Cost Performance Evolutions of the Proton Exchange Membrane Fuel Cell Power Generation
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作者 H. F. Zhang P. C. Pei 《Energy and Power Engineering》 2013年第2期1-10,共10页
This paper aims at formulization and overview of the cost performance evolutions of proton exchange membrane (PEM) fuel cell power generation along with load and time. For this purpose, electricity-cost ratio (ECR) is... This paper aims at formulization and overview of the cost performance evolutions of proton exchange membrane (PEM) fuel cell power generation along with load and time. For this purpose, electricity-cost ratio (ECR) is proposed as the measuring parameter for the cost performance and a two-constant cost model is proposed to concisely describe the cost characteristic of the power generation as the opposite of a multi-constant cost model. Combination of the two-constant cost model and the ideal cell model developed recently produces an inclusive ECR equation that has three analytical expressions and thus allows of straight overviews of the cost performance evolutions in the working zones of the cells. The applications to real cells confirm the validity of the equation for operation optimization and technique evaluation of PEM fuel cells. And more insights into the cost performance evolutions are inferred by means of the equation to help promote the commercialization of PEM fuel cells. 展开更多
关键词 FUEL Cell cost performance LIFETIME DEGRADATION Energy Efficiency Operation Optimization
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Discrimination and Estimation of the Maximum Cost Performance of Proton Exchange Membrane Fuel Cell Power Generation with Seven Constants
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作者 H. F. Zhang P. C. Pei 《Energy and Power Engineering》 2013年第2期55-75,共21页
This paper is dedicated to analytical expression of the maximum electricity-cost ratio (M-ECR) point of the proton exchange membrane (PEM) fuel cell power generation as the function of cell constants and cost constant... This paper is dedicated to analytical expression of the maximum electricity-cost ratio (M-ECR) point of the proton exchange membrane (PEM) fuel cell power generation as the function of cell constants and cost constants. That is to formulize the maximum cost performance (MCP) magnitude and the optimal final operating (OFO) location in the working zone based on the five-constant ideal cell model and the two-constant cost model. The issues are well resolved by introducing the concepts of economic voltage and cost factor and describing the movement of the M-ECR point with cost factor. According to mathematical derivations, the movement can be described in the form of MCP and OFO curves. The derivations lead to a complete set of discriminants and criteria of the M-ECR point of PEM fuel cells that theoretically cover all of cell specialties and all of cost specialties. The discriminants and criteria may act as a general tool for the operation optimization of a diversity of PEM fuel cells and the economic viability estimation of the power generation. 展开更多
关键词 Fuel Cell Working Zone ECONOMIC VIABILITY COMMERCIALIZATION cost performance Operation Optimization
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Effects of dietary protein/energy ratio on growth performance,carcass trait,meat quality,and plasma metabolites in pigs of different genotypes 被引量:40
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作者 Yingying Liu Xiangfeng Kong +6 位作者 Guoli Jiang Bi'e Tan Jinping Deng Xiaojian Yang Fengna Li Xia Xiong Yulong Yin 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2015年第4期435-444,共10页
Background: The protein/energy ratio is important for the production performance and utilization of available feed resources by animals. Increased protein consumption by mammals leads to elevated feed costs and incre... Background: The protein/energy ratio is important for the production performance and utilization of available feed resources by animals. Increased protein consumption by mammals leads to elevated feed costs and increased nitrogen release into the environment. This study aimed to evaluate the effects of dietary protein/energy ratio on the growth performance, carcass traits, meat quality, and plasma metabolites of pigs of different genotypes. Methods: Bama mini-pigs and Landrace pigs were randomly assigned to two dietary treatment groups (Chinese conventional diet with low protein/energy ratio or National Research Council diet with high protein/energy ratio; n = 24 per treatment) in a 2 x 2 factorial arrangement. Blood and muscle samples were collected at the end of the nursery, growing, and finishing phases. Results: We observed significant interactions (P 〈 0.05) between breed and diet for total fat percentage, intramuscular fat (IMF) content, protein content in biceps femoris (BF) muscle, and plasma urea nitrogen (UN) concentration in the nursery phase; for average daily gain (ADG), average daily feed intake (ADFI), dry matter, IMF content in psoas major (PM) muscle, and plasma total protein and albumin concentrations in the growing phase; and for drip loss and plasma UN concentration in the finishing phase. Breed influenced (P 〈 0.05) growth performance, carcass traits, and meat quality, but not plasma metabolites. Throughout the trial, Landrace pigs showed significantly higher (P 〈 0.0_5) ADG, ADFI, dressing percentage, lean mass rate, and loin-eye area than did Bama mini-pigs, but significantly lower (P 〈 0.0.5) feed/gain ratio, fat percentage, backfat thickness, and IMF content. Dietary protein/energy ratio influenced the pH value, chemical composition of BF and PM muscles, and plasma activities of glutamic-pyruvic transaminase and gamma-glutamyl transpeptidase, and plasma concentration of UN. Conclusions: Compared with Landrace pigs, Bama mini-pigs showed slower growth and lower carcass performance, but had better meat quality. Moreover, unlike Landrace pigs, the dietary protein/energy ratio did not affect the growth performance of Bama mini-pigs. These results suggest that, in swine production, low dietary protein/energy ratio may be useful for reducing feed costs and minimizing the adverse effects of ammonia release into the environment. 展开更多
关键词 Dietary protein/energy ratio Growth performance Meat quality MINI-PIG Plasma metabolites
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Realization and Analysis of Good Fuel Economy and Kinetic Performance of a Low-cost Hybrid Electric Vehicle 被引量:7
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作者 WANG Lei ZHANG Jianlong YIN Chengliang ZHANG Yong WU Zhiwei 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2011年第5期774-789,共16页
By using high-power and high-efficiency propulsion systems,current hybrid electric vehicles(HEVs) in market can achieve excellent fuel economy and kinetic performance.However,it is the cost of current HEVs that hind... By using high-power and high-efficiency propulsion systems,current hybrid electric vehicles(HEVs) in market can achieve excellent fuel economy and kinetic performance.However,it is the cost of current HEVs that hinders HEVs coming into widespread use.A novel hybrid electric propulsion system is designed to balance HEV cost and performance for developing markets.A battery/supercapacitor-based hybrid energy storage system(HESS) is used to improve energy conversion efficiency and reduce battery size and cost.An all-in-one-controller(AIOC) which integrates engine electronic control unit(ECU),motor ECU,and HESS management system is developed to save materials and energy,and reduce the influence of distribution parameters on circuit.As for the powertrain configuration,four schemes are presented:belt-driven starter generator(BSG) scheme,four-wheel drive HEV scheme,full HEV scheme,and ranger-extender electric vehicle(EV) scheme.Component selection and parameter matching for the propulsion system are performed,and an energy management strategy is developed based on powertrain configuration and selected components.Forward-facing simulation models are built,comprehending the control strategy based on the optimal engine torque for the low-cost hybrid electric propulsion system.Co-simulation of AVL CRUISE and Matlab/Simulink is presented and the best scheme is selected.The simulation results indicate that,for the best design,fuel consumption in urban driving condition is 4.11 L/(100 km) and 0-50 km/h accelerating time is 10.95 s.The proposed research can realize low-cost concept for HEV while achieving satisfactory fuel economy and kinetic performance,and help to improve commercialization of HEVs. 展开更多
关键词 low-cost hybrid electric vehicle hybrid energy storage system(HESS) fuel economy kinetic performance co-simulation cost and performance tradeoff
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A novel model for cost performance evaluation of pulverized coal injected into blast furnace based on effective calorific value 被引量:4
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作者 徐润生 张建良 +3 位作者 左海滨 李克江 宋腾飞 邵久刚 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第10期3990-3998,共9页
The combustion process of pulverized coal injected into blast furnace involves a lot of physical and chemical reactions. Based on the combustion behaviors of pulverized coal, the conception of coal effective calorific... The combustion process of pulverized coal injected into blast furnace involves a lot of physical and chemical reactions. Based on the combustion behaviors of pulverized coal, the conception of coal effective calorific value representing the actual thermal energy provided for blast furnace was proposed. A cost performance evaluation model of coal injection was built up for the optimal selection of various kinds of coal based on effective calorific value. The model contains two indicators: coal effective calorific value which has eight sub-indicators and coal injection cost which includes four sub-indicators. In addition, the calculation principle and application of cost performance evaluation model in a Chinese large-scale iron and steel company were comprehensively introduced. The evaluation results finally confirm that this novel model is of great significance to the optimal selection of blast furnace pulverized coal. 展开更多
关键词 blast furnace pulverized coal injection effective calorific value cost performance evaluation model
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Low cost, high performance supercapacitor electrode using coconut wastes: eco-friendly approach 被引量:1
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作者 Divyashree A. Shoriya Aruni Bt Abdul Manaf +3 位作者 Yallappa S. Chaitra K. Kathyayini N. Gurumurthy Hegde 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2016年第5期880-887,共8页
Low cost, high performance supercapacitor electrodes were fabricated using coconut waste as precursor. Simple one step pyrolysis is adopted to get the spherical shaped particle where lignocellulosic nature of carbon c... Low cost, high performance supercapacitor electrodes were fabricated using coconut waste as precursor. Simple one step pyrolysis is adopted to get the spherical shaped particle where lignocellulosic nature of carbon converts into porous carbon nanospheres. Three types of coconut wastes, namely, coconut fiber(CF), coconut leaves(CL) and coconut stick(CS) have been studied and compared for their application in supercapacitors. Uniform spherical shape with particle size ranging from 30 to 60 nm for leaves and sticks and20 nm for fibers was obtained. The electrochemical properties of the porous carbon nanospheres were studied using cyclic voltammetry(CV), chronopotentiometry(CP) and electrochemical impedance spectroscopy(EIS). The porous carbon nanospheres derived from all the three biowaste samples show good electrochemical performance for supercapacitor application. Porous carbon nanospheres derived from coconut fiber exhibited maximum specific capacitance of 236 F/g followed by coconut stick and coconut leaves with 208 and 116 F/g respectively at a scan rate of 2 m V/s. Further impedance studies showed a charge transfer resistance of 4.9 for the porous carbon nanospheres derived from coconut fiber, while those from coconut leaves and coconut stick exhibited a slightly higher resistance of 6 and14.2, respectively. The simple eco-friendly approach we have demonstrated for synthesizing coconut waste based carbon nanospheres makes them excellent candidates for future, low-cost, energy storage devices. 展开更多
关键词 Low cost Coconut waste BIOWASTE High performance SUPERCAPACITOR Energy storage
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Effects of Dietary Concentrate to Forage Ratios on Production Performance and Serum Biochemical Indicators in Post-fattening Hainan Yellow Cattle 被引量:4
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作者 Wang Feng Wei Limin +6 位作者 Zheng Xinli Liu Hailong Sun Ruiping Chao Zhe Huang Lili Fu Liang Liu Quanwei 《Animal Husbandry and Feed Science》 CAS 2020年第1期17-20,35,共5页
[Objective]The paper was to investigate the effects of dietary concentrate to forage ratios on production performance and serum bio-chemical indicators of post-fattening Hainan Yellow Cattle.[Method]Sixteen Hainan Yel... [Objective]The paper was to investigate the effects of dietary concentrate to forage ratios on production performance and serum bio-chemical indicators of post-fattening Hainan Yellow Cattle.[Method]Sixteen Hainan Yellow Cattles with the same genetic backgrounds and similar initial weight of(242.22 ±0.71 kg) were randomly divided into four treatments.Cattles were fed with diets of different concentrate to forage ratios(20:80, group Ⅰ;30:70, Group Ⅱ;40:60, group Ⅲ;50:50, group Ⅳ).The trial lasted 62 d.[Result]The daily gain in experimental group Ⅳ was significantly higher than that in experimental group Ⅱ(P<0.05), but the feed gain ratio in experimental group Ⅳ was lower than those in other ex-perimental groups(P>0.05).The feed intake in experimental group Ⅳ was also markedly higher than those in experimental groups Ⅰ and Ⅱ(P<0.05).Compared with the experimental group Ⅱ, the gross profit of experimental group Ⅳ was significantly promoted(P<0.05).The alanine aminotransferase and aspartate aminotransferase activities in experimental group Ⅱ were markedly higher than those in experimental groups Ⅰ, Ⅲ and Ⅳ.[Conclusion]When the dietary concentrate to forage ratios was 50∶50, the production performance of post-fattening Hainan Yellow Cattle was better. 展开更多
关键词 Concentrate to FORAGE ratios HAINAN YELLOW CATTLE Growth performance Economic benefits SERUM biochemical indicator
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Effects of Diets with Different Corn-to-Soybean Ratios on Performance of Lactational Rex Rabbits 被引量:1
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作者 SUN Li-na GU Zi-lin LIU Ya-juan LI Su-min 《Animal Husbandry and Feed Science》 CAS 2010年第1期24-26,31,共4页
[ Objective] To study the effects of diets with different com-to-soybean ratios on production performance of lactational Rex rabbits and select the best feed formula. [Method] A total of 80 lactational healthy Rex rab... [ Objective] To study the effects of diets with different com-to-soybean ratios on production performance of lactational Rex rabbits and select the best feed formula. [Method] A total of 80 lactational healthy Rex rabbits (similar age, body weight and delivery time) were randomly divided into five groups, 16 in each group. The Rex rabbits in group I were fed with corn-based meal diet, group II with soybean-based meal diet, group III with the developed corn-soybean meal diet, group IV with corn-soybean meal free diet, and group CK with conventional corn-soybean meal diet. During the lactation period, the changes in the lactation performance, growth rate of baby rabbits, weight and feed costs were observed. [ Result] The lactation performance of mother rabbits and the growth rate of baby rabbits in the experimental groups were similar to that in the control group. The weaning survival rate of the group III was the highest, but it was not significantly higher than that of the control group. The weaning survival rate of the other three groups was lower than that of the control group (P〈0.05). The weight loss of mother rabbits in the group I, II and III was not significantly different from that of the control group, but the weight loss of the group IV was higher than that of the control group ( P 〈 0.01 ). [ Conclusion] Diets with appropriate corn-to-soybean ratios not only reduce feed costs but also give the best feeding effects. 展开更多
关键词 Lactational Rex rabbits Lactation performance Growth rate WEIGHT Feed costs
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Investigation of short-channel design on performance optimization effect of Hall thruster with large height–radius ratio 被引量:1
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作者 Haotian FAN Yongjie DING +3 位作者 Chunjin MO Liqiu WEI Hong LI Daren YU 《Plasma Science and Technology》 SCIE EI CAS CSCD 2022年第2期1-9,共9页
In this study,the neutral gas distribution and steady-state discharge under different discharge channel lengths were studied via numerical simulations.The results show that the channel with a length of 22 mm has the a... In this study,the neutral gas distribution and steady-state discharge under different discharge channel lengths were studied via numerical simulations.The results show that the channel with a length of 22 mm has the advantage of comprehensive discharge performance.At this time,the magnetic field intensity at the anode surface is 10%of the peak magnetic field intensity.Further analysis shows that the high-gas-density zone moves outward due to the shortening of the channel length,which optimizes the matching between the gas flow field and the magnetic field,and thus increases the ionization rate.The outward movement of the main ionization zone also reduces the ion loss on the wall surface.Thus,the propellant utilization efficiency can reach a maximum of 96.8%.Moreover,the plasma potential in the main ionization zone will decrease with the shortening of the channel.The excessively short-channel will greatly reduce the voltage utilization efficiency.The thrust is reduced to a minimum of 46.1 m N.Meanwhile,because the anode surface is excessively close to the main ionization zone,the discharge reliability is also difficult to guarantee.It was proved that the performance of Hall thrusters can be optimized by shortening the discharge channel appropriately,and the specific design scheme of short-channel of HEP-1350 PM was defined,which serves as a reference for the optimization design of Hall thruster with large height–radius ratio.The shortchannel design also helps to reduce the thruster axial dimension,further consolidating the advantages of lightweight and large thrust-to-weight ratio of the Hall thruster with large height–radius ratio. 展开更多
关键词 Hall thruster large height-radius ratio short-channel design discharge performance numerical simulation
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The Influence of Blocking Mass Parameters on the Vibration Isolation Performance of a Power Cabin 被引量:1
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作者 计方 姚熊亮 叶曦 《Journal of Marine Science and Application》 2011年第1期25-32,共8页
Rigid blocking masses are located in the typical base structure of a power cabin based on the impedance mismatch principle.By combining the acoustic-structural coupling method and statistical energy analysis,the full-... Rigid blocking masses are located in the typical base structure of a power cabin based on the impedance mismatch principle.By combining the acoustic-structural coupling method and statistical energy analysis,the full-band vibration and sound radiation reduction effect of vibration isolation masses located in a base structure was researched.The influence of the blocking mass’ cross-section size and shape parameters and the layout location of the base isolation performance was discussed.Furthermore,the effectiveness of rigid vibration isolation design of the base structure was validated.The results show that the medium and high frequency vibration and sound radiation of a power cabin are effectively reduced by a blocking mass.Concerning weight increment and section requirement,suitably increasing the blocking mass size and section height and reducing section width can result in an efficiency-cost ratio. 展开更多
关键词 rigid isolation blocking mass parameters power cabin vibration isolation performance efficiency-cost ratio
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Study on Filtration Performance of Silica/ Alumina Slurry in the Process of Recycling Mother Liquor of NaY Zeolite 被引量:1
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作者 Guo Yaoqing Ma Yuelong Deng Jinghui(Research Institute of Petroleum Processing, Beijing 100083) 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2004年第1期49-54,共6页
In order to recover the SiO_2 contained in the mother liquor in the course ofNaY zeolite synthesis to minimize pollution, the influence of various preparation conditions on thefiltering velocity of gel slurry was stud... In order to recover the SiO_2 contained in the mother liquor in the course ofNaY zeolite synthesis to minimize pollution, the influence of various preparation conditions on thefiltering velocity of gel slurry was studied using the SiO_2/Al_2O_3 gel recovered from the NaYmother liquor in the laboratory. The results of study had shown that at a SiO_2/Al_2O_3 ratio in thefeed equating to 9∶1 the SiO_2 recovery rate and Al_2O_3 utilization rate were high with a fasterflow velocity of the filtrate. The pH value of the system had great impact on the flow velocity offiltrate. Between the two methods for regulating the pH value, the one for formation ofsilica/alumina gel slurry by addition of sulfuric acid prior to adding aluminium sulfate in thesolution could secure a faster filtration velocity. The filtration velocity was decreased in tandemwith increasing SiO_2 concentration in mother liquor, meanwhile an increase in dry filter cakeyield. 展开更多
关键词 NaY zeolite mother liquor filtration performance Si/Al ratio GEL wasteutilization laboratory scale
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Quantitative Comparative Study of the Performance of Lossless Compression Methods Based on a Text Data Model
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作者 Namogo Silué Sié Ouattara +1 位作者 Mouhamadou Dosso Alain Clément 《Open Journal of Applied Sciences》 2024年第7期1944-1962,共19页
Data compression plays a key role in optimizing the use of memory storage space and also reducing latency in data transmission. In this paper, we are interested in lossless compression techniques because their perform... Data compression plays a key role in optimizing the use of memory storage space and also reducing latency in data transmission. In this paper, we are interested in lossless compression techniques because their performance is exploited with lossy compression techniques for images and videos generally using a mixed approach. To achieve our intended objective, which is to study the performance of lossless compression methods, we first carried out a literature review, a summary of which enabled us to select the most relevant, namely the following: arithmetic coding, LZW, Tunstall’s algorithm, RLE, BWT, Huffman coding and Shannon-Fano. Secondly, we designed a purposive text dataset with a repeating pattern in order to test the behavior and effectiveness of the selected compression techniques. Thirdly, we designed the compression algorithms and developed the programs (scripts) in Matlab in order to test their performance. Finally, following the tests conducted on relevant data that we constructed according to a deliberate model, the results show that these methods presented in order of performance are very satisfactory:- LZW- Arithmetic coding- Tunstall algorithm- BWT + RLELikewise, it appears that on the one hand, the performance of certain techniques relative to others is strongly linked to the sequencing and/or recurrence of symbols that make up the message, and on the other hand, to the cumulative time of encoding and decoding. 展开更多
关键词 Arithmetic Coding BWT Compression ratio Comparative Study Compression Techniques Shannon-Fano HUFFMAN Lossless Compression LZW performance REDUNDANCY RLE Text Data Tunstall
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Research on the Impact of Digital Transformation on the Performance of Manufacturing Enterprises
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作者 Longfei Ma Thanaphon Ratchatakulpat Gumporn Supasettaysa 《Proceedings of Business and Economic Studies》 2024年第4期16-22,共7页
To address the challenges faced by manufacturing enterprises in digital transformation,this paper analyzes the relationship between digital transformation and enterprise performance.Using panel data from domestic A-sh... To address the challenges faced by manufacturing enterprises in digital transformation,this paper analyzes the relationship between digital transformation and enterprise performance.Using panel data from domestic A-share-listed manufacturing enterprises from 2012 to 2022,two hypotheses were proposed.The analysis and verification revealed that digital transformation in manufacturing enterprises can enhance performance and reduce costs.Based on the impact of digital transformation on manufacturing enterprise performance,optimization suggestions are proposed to guide future digital transformation and performance improvement efforts in these enterprises. 展开更多
关键词 Digital transformation Manufacturing enterprise performance costS
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Different dietary methionine to lysine ratios in the lactation diet:effects on the performance of sows and their offspring and methionine metabolism in lactating sows
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作者 Hongkui Wei Xichen Zhao +5 位作者 Mao Xia Chengquan Tan Jun Gao John KHtoo Chuanhui Xu Jian Peng 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2020年第1期121-131,共11页
Background:Over the last decade,the nutritional requirements of lactating modern genotype sows have increased.The current nutritional recommendations might be unable to meet the needs of increased litter size and milk... Background:Over the last decade,the nutritional requirements of lactating modern genotype sows have increased.The current nutritional recommendations might be unable to meet the needs of increased litter size and milk production,and thus the nutritional requirements need to be re-evaluated.The current study was conducted to investigate the effects of dietary methionine to lysine(Met:Lys)ratios on the performance of and methionine metabolism in lactating sows.Results:During the 1st week of lactation,piglets reared on sows in the 0.37 to 0.57 Met:Lys ratio groups grew faster than those reared on sows in the control group(0.27)(P<0.01).The 0.37-ratio group showed increased levels of GSHPx in plasma during lactation(P<0.01)and decreased concentrations of urea nitrogen in the plasma of sows(P<0.05).Compared with the 0.27-ratio group,the levels of T-AOC and GSH-Px in the plasma and homocysteine in the milk of lactating sows were significantly increased in sows in the 0.47-ratio group(P<0.01).In sows fed a 0.57-ratio diet,the levels of glutathione and taurine in the plasma and milk were improved significantly during lactation.However,the content of TBARS in the blood(P<0.05 at day 7 and P=0.06 at weaning day)was increased(P<0.01).Moreover,there were linear increases in the levels of homocysteine in the blood and milk of sows during the lactation period(P<0.01)with increased dietary Met:Lys ratios in the lactation diet.Conclusions:The current study indicated that increasing the dietary Met:Lys ratio(0.37~0.57)in the lactation diet had no significant effect on the overall performance of sows or the colostrum and milk composition,but it increased piglet mean BW and piglet ADG during the first week of lactation.Increasing dietary methionine levels had no significant effect on antioxidant function in lactation sows,even though it increased levels of GSH and GSH-Px in the plasma of sows during lactation.However,the content of homocysteine in the plasma and milk increased during lactation due to a high level of dietary methionine. 展开更多
关键词 LACTATION METHIONINE Met to Lys ratios Oxidative stress PIGLET growth performance SOW performance
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Effects of Feeding Time on the Growth Performance and Variation of RNA/DNA Ratio of the Chinese Soft-shelled Turtle, Pelodiscus sinensis
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作者 Yingguang jI Haiyan LIU +1 位作者 Zhe SONG Zhencai YANG 《Asian Herpetological Research》 SCIE CSCD 2016年第4期271-277,共7页
The present study was to investigate the effects of feeding time on growth of the Chinese soft-shelled turtle. The experiment was carried out with a photoperiod of 12L (light): 12D (dark) with lights on at 06:00... The present study was to investigate the effects of feeding time on growth of the Chinese soft-shelled turtle. The experiment was carried out with a photoperiod of 12L (light): 12D (dark) with lights on at 06:00 and off at 18:00. Turtles were maintained at a temperature of 32 - 0.2 ℃ in tanks throughout the length of the experiment. The turtles in group 1 to group 6 were fed respectively at 00:00, 04:00, 08:00, 12:00, 16:00 and 20:00 with 60 turtles each (Initial body weight 88.27 - 0.09 g). Acrophases of postprandial RNA/DNA ratio in liver in each group was shown between 5h and 7h after feeding. A positive linear correlation could be seen between specific growth rate (SGR) and RNA/ DNA:SGR=t.1586RNA/DNA-0.7097 (r = 0.9328, P = 0.0066). The results indicated that the values at the acrophases of about 6h after feeding might be used as an instantaneous growth index in the Chinese soft-shelled turtle. The turtles in group 1 grew better than group 3, group 4, group 5, group 6, because they ate more, but they ate more and grew slower than group 2, whose feed conversion rate was also higher. Meanwhile, the SGR and feeding rate of turtles fed at 12:00 were the lowest from the six groups (P 〈 0.05). Turtles fed in group 1, group 2 and group 6 developed more heavy final body weight (FBW), higher feeding rate and SGR than the other three groups. This probably suggested that turtles fed in scotophase grew better than that fed at photophase in total. 展开更多
关键词 Feeding time Growth performance Pelodiscus sinensis RNA/DNA ratio
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Experimental Investigation on Combustion Performance of Solid Propellant Subjected to Erosion of Particles with Different Concentrations
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作者 卢明章 赵志博 +1 位作者 何国强 刘佩进 《Defence Technology(防务技术)》 SCIE EI CAS 2011年第2期87-92,共6页
A test device with rectangular channel is developed to study the combustion performance of solid propellant in high temperature particles erosion.The flowfields in this newdevice and a test device with circular channe... A test device with rectangular channel is developed to study the combustion performance of solid propellant in high temperature particles erosion.The flowfields in this newdevice and a test device with circular channels are simulated numerically.The particle erosion experiments in these two devices are carried out under different particle concentrations.The results showthat the test device with rectangular channel can effectively improve the clarity and precision of combustion diagnosis image and can be used for research on combustion performance of solid propellant under lowconcentration particle erosion;the circular channel device has good particle convergent effect,provides high concentration particle erosion,and can be used for research on the combustion performance of solid propellant under high concentration particle erosion.The experiment data indicates that the propellant burning rate does not change obviously in lower particle concentration;the propellant with lower static burning rate increases remarkably under particle erosion,while the propellant with high static burning rate is not sensitive to the particle erosion. 展开更多
关键词 propulsion system of aviation &aerospace solid propellant particle erosion combustion performance maximum burning rate increment ratio
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Effect of Pelleted Total Mixed Ration with Different Concentrate-roughage Ratios on Production Performance and Serum Biochemical Parameters of Fattening Hainan Black Goats
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作者 Liu Quanwei Wang Feng +5 位作者 Wei Limin Tan Shuyi Sun Ruiping Huang Lili Xing Manping Zheng Xinli 《Animal Husbandry and Feed Science》 CAS 2019年第1期4-8,共5页
[Objective] This paper was to study effects of pelleted total mixed ration with different concentrate-roughage ratios on production performance and serum biochemical parameters of fattening Hainan black goats.[Method]... [Objective] This paper was to study effects of pelleted total mixed ration with different concentrate-roughage ratios on production performance and serum biochemical parameters of fattening Hainan black goats.[Method] Thirty-six fattening Hainan black goats with the same genetic background and similar initial weight of(14.08±0.13) kg were randomly assigned into three treatments. Goats were fed with Juncao + concentrate(control group), pelleted total mixed ration I(concentrate: roughage 50 ∶50, group Ⅰ) and Ⅱ(concentrate: roughage 45∶55, group Ⅱ), respectively. The test lasted 45 d.[Result] The final weight, daily gain and feed intake of rams in experimental group Ⅰ were significantly higher than those of control group and experimental group Ⅱ(P<0.05);the final weight and daily gain of rams in experimental group Ⅰ were also markedly higher than those of experimental group Ⅱ(P<0.05);the feed/gain of rams in experimental group Ⅰ was significantly lower than those in control group and experimental group Ⅱ(P<0.05). The feed gain cost of rams in experimental group Ⅰ was markedly lower than that in experimental group Ⅱ( P<0.05), but was significantly higher than that in experimental group Ⅰ(P<0.05);the gross profit of rams in experimental group Ⅰ was significantly higher than those in control group and experimental group Ⅱ(P<0.05). Compared with control group and experimental group Ⅱ, the serum total protein and glucose lev-els in experimental group Ⅱ increased significantly(P<0.05), but the urea nitrogen content reduced(P>0.05).[Conclusion] When the concentrateroughage ratio of pelleted total mixed ration was 50∶50, the fattening effect of Hainan black goat was better, and the serum total protein and glucose levels were evidently improved. 展开更多
关键词 FATTENING HAINAN black GOAT Pelleted total mixed ration Concentrate-roughage ratio Production performance SERUM BIOCHEMICAL parameters
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Performance Framework for Virtual Machine Migration in Cloud Computing
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作者 Tahir Alyas Taher M.Ghazal +4 位作者 Badria Sulaiman Alfurhood Munir Ahmad Ossma Ali Thawabeh Khalid Alissa Qaiser Abbas 《Computers, Materials & Continua》 SCIE EI 2023年第3期6289-6305,共17页
In the cloud environment,the transfer of data from one cloud server to another cloud server is called migration.Data can be delivered in various ways,from one data centre to another.This research aims to increase the ... In the cloud environment,the transfer of data from one cloud server to another cloud server is called migration.Data can be delivered in various ways,from one data centre to another.This research aims to increase the migration performance of the virtual machine(VM)in the cloud environment.VMs allow cloud customers to store essential data and resources.However,server usage has grown dramatically due to the virtualization of computer systems,resulting in higher data centre power consumption,storage needs,and operating expenses.Multiple VMs on one data centre manage share resources like central processing unit(CPU)cache,network bandwidth,memory,and application bandwidth.Inmulti-cloud,VMmigration addresses the performance degradation due to cloud server configuration,unbalanced traffic load,resource load management,and fault situations during data transfer.VMmigration speed is influenced by the size of the VM,the dirty rate of the running application,and the latency ofmigration iterations.As a result,evaluating VM migration performance while considering all of these factors becomes a difficult task.Themain effort of this research is to assess migration problems on performance.The simulation results in Matlab show that if the VMsize grows,themigration time of VMs and the downtime can be impacted by three orders ofmagnitude.The dirty page rate decreases,themigration time and the downtime grow,and the latency time decreases as network bandwidth increases during the migration time and post-migration overhead calculation when the VMtransfer is completed.All the simulated cases of VMs migration were performed in a fuzzy inference system with performance graphs. 展开更多
关键词 LATENCY cloud computing dirty page ratio storage migration performance
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Growth Performance, Feed Conversion Ratio and Economics of Production of Native and Crossbred (Local x Holstein Friesian) Bulls for Fattening under Different Improved Feeding
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作者 Mohammad Abu Bakkur Siddque Nathu Ram Sarker +2 位作者 Mohammad Abdul Hamid Mohammad Nurul Amin Monira Sultana 《Journal of Agricultural Science and Technology(A)》 2015年第9期770-781,共12页
An experiment was conducted to evaluate the growth performance and cost per gain of indigenous and crossbred (local x Holstein Friesian (L x HF)) bulls under four different improved feed treatments to determine th... An experiment was conducted to evaluate the growth performance and cost per gain of indigenous and crossbred (local x Holstein Friesian (L x HF)) bulls under four different improved feed treatments to determine the appropriate ration for economic organic beef production in Bangladesh. Twenty indigenous bulls (average body weight 208.08 ± 13.98 kg) and 20 crossbred (L x l-IF) bulls (average body weight 256.26 ± 26.85 kg) of 24 months age were divided into four equal groups and fed on four diets (T0, T1, T2 and T3) up to 120 d, where To referred to the conventional diet, and T1, T2 and T3 referred as improved organic diets. Required dry matter for individual animal was supplied by roughage and concentrate sources of the ration in the ratio of 2:1. Local grass and paddy straw were supplied to group T0 and T1, Napier grass and straw to group T2, and Napier grass (Pennisetum purpureum), straw and Ipil-ipil leaf (Leuceana leucucephala) to group Ts as roughage; whereas, the concentrate was supplied as 1.5% of live weight. The results revealed that total dry matter intake (DMI), total DMI as percent live weight (%LW), feed conversion ratio (FCR) and average daily gain (ADG) varied significantly (P 〈 0.01) among different treatment groups. Breed also had significant (P 〈 0.01) effect on total DMI, FCR and ADG, but total DMI (%LW) was not affected by breed type. Feed cost expressed as per kg live weight gain (LWG) (BDT/kg LWG; 1USD = 78.95 BDT), were also affected (P 〈 0.01) by feed treatments and breed type. Indigenous and crossbred bulls fed diet T3 had higher ADG (0.49 kg and 1.17 kg, respectively) and comparatively lower feed costs (156 BDT/kg LWG and 96.78 BDT/kg LWG, respectively). But crossbred (L × HF) bulls showed the highest ADG (1.17 kg) and the lowest feed cost (96.78 BDT/kg LWG). Therefore, considering the growth performance and cost per kg gain of the experimental animals, it may be concluded that the crossbred (Lx HF) bulls treated with T3 diet may be used for economic organic beef production in Bangladesh. 展开更多
关键词 Feed treatment growth performance FCR cost per gain.
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