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MULTIFRACTAL ANALYSIS OF CONVERGENCE EXPONENTS FOR PRODUCTS OF CONSECUTIVE PARTIAL QUOTIENTS IN CONTINUED FRACTIONS
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作者 Lulu FANG Jihua MA +1 位作者 Kunkun SONG Xin YANG 《Acta Mathematica Scientia》 SCIE CSCD 2024年第4期1594-1608,共15页
For each real number x∈(0,1),let[a_(1)(x),a_(2)(x),…,a_n(x),…]denote its continued fraction expansion.We study the convergence exponent defined byτ(x)=inf{s≥0:∞∑n=1(a_(n)(x)a_(n+1)(x))^(-s)<∞},which reflect... For each real number x∈(0,1),let[a_(1)(x),a_(2)(x),…,a_n(x),…]denote its continued fraction expansion.We study the convergence exponent defined byτ(x)=inf{s≥0:∞∑n=1(a_(n)(x)a_(n+1)(x))^(-s)<∞},which reflects the growth rate of the product of two consecutive partial quotients.As a main result,the Hausdorff dimensions of the level sets ofτ(x)are determined. 展开更多
关键词 continued fractions product of partial quotients Hausdorff dimension
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An improved cross entropy algorithm for steelmaking-continuous casting production scheduling with complicated technological routes 被引量:8
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作者 王桂荣 李歧强 王鲁浩 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第8期2998-3007,共10页
In order to increase productivity and reduce energy consumption of steelmaking-continuous casting(SCC) production process, especially with complicated technological routes, the cross entropy(CE) method was adopted to ... In order to increase productivity and reduce energy consumption of steelmaking-continuous casting(SCC) production process, especially with complicated technological routes, the cross entropy(CE) method was adopted to optimize the SCC production scheduling(SCCPS) problem. Based on the CE method, a matrix encoding scheme was proposed and a backward decoding method was used to generate a reasonable schedule. To describe the distribution of the solution space, a probability distribution model was built and used to generate individuals. In addition, the probability updating mechanism of the probability distribution model was proposed which helps to find the optimal individual gradually. Because of the poor stability and premature convergence of the standard cross entropy(SCE) algorithm, the improved cross entropy(ICE) algorithm was proposed with the following improvements: individual generation mechanism combined with heuristic rules, retention mechanism of the optimal individual, local search mechanism and dynamic parameters of the algorithm. Simulation experiments validate that the CE method is effective in solving the SCCPS problem with complicated technological routes and the ICE algorithm proposed has superior performance to the SCE algorithm and the genetic algorithm(GA). 展开更多
关键词 steelmaking continuous casting production scheduling complicated technological routes cross entropy powerconsumption
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Cleaner production for continuous digester processes based on hybrid Pareto genetic algorithm
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作者 JIN Fu\|jiang, WANG Hui, LI Ping (Institute of Industrial Process Control, Zhejiang University, Hangzhou 310027, China. 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2003年第1期129-135,共7页
Pulping production process produces a large amount of wastewater and pollutant emitted, which has become one of the main pollution sources in pulp and paper industry. To solve this problem, it is necessary to implemen... Pulping production process produces a large amount of wastewater and pollutant emitted, which has become one of the main pollution sources in pulp and paper industry. To solve this problem, it is necessary to implement cleaner production by using modeling and optimization technology. This paper studies the modeling and multi\|objective genetic algorithms for continuous digester process. First, model is established, in which environmental pollution and saving energy factors are considered. Then hybrid genetic algorithm based on Pareto stratum\|niche count is designed for finding near\|Pareto or Pareto optimal solutions in the problem and a new genetic evaluation and selection mechanism is proposed. Finally using the real data from a pulp mill shows the results of computer simulation. Through comparing with the practical curve of digester,this method can reduce the pollutant effectively and increase the profit while keeping the pulp quality unchanged. 展开更多
关键词 cleaner production multi\|objective optimization genetic algorithm Pareto stratum concentration of residual alkali Kamyr continuous digester
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The startup and production of the No.4 slab continuous caster at Baosteel
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作者 Zhi Jianjun Yu Zuda Hou Angui Wang Hongbing Hu Huijun Zong Zhenyu 《Baosteel Technical Research》 CAS 2008年第3期60-64,共5页
In order to meet the developing requirements for the output and quality of the products of Baosteel, the No. 4 slab continuous caster designed by the Danieli Company of Italy was built. Since starting up in December, ... In order to meet the developing requirements for the output and quality of the products of Baosteel, the No. 4 slab continuous caster designed by the Danieli Company of Italy was built. Since starting up in December, 2006, the casting machine has run smoothly in the aspects of production and quality control. It is equipped with advanced apparatus and technology, such as electric magnetic braking (EMBR) and soft reduction. Some operation indices have been continually improved, in order to ensure that slab quality meets the requirements of downstream products. Its total output reached 2.17 Mt in 2007. This study analyzes the operational indices and the slab quality. 展开更多
关键词 SLAB continuous casting product variety QUALITY
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Study on the Effect of "Crayfish-Rice Continuous Cropping" on Grain Production:A Case Study of Hubei Province
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作者 Qifei TANG 《Asian Agricultural Research》 2019年第9期20-23,共4页
Taking Hubei Province as an example,starting with the present situation and existing problems of grain production,this paper expounds the great significance of"crayfish-rice continuous cropping"model in impr... Taking Hubei Province as an example,starting with the present situation and existing problems of grain production,this paper expounds the great significance of"crayfish-rice continuous cropping"model in improving grain quality,and analyzes the beneficial influence of"crayfish-rice continuous cropping"on grain production and the difficulties it faces.This paper also puts forward some measures and suggestions for the further popularization of"crayfish-rice continuous cropping"in order to maintain food security. 展开更多
关键词 Green agriculture Crayfish-rice continuous CROPPING GRAIN production HUBEI Province
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Improved Cross Entropy Algorithm for Steelmaking Continuous Casting Production Scheduling with Minimum Power Consumption
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作者 王桂荣 李歧强 杨凡 《Journal of Donghua University(English Edition)》 EI CAS 2015年第1期23-29,共7页
A matrix encoding scheme for the steelmaking continuous casting( SCC) production scheduling( SCCPS) problem and the corresponding decoding method are proposed. Based on it,a cross entropy( CE) method is adopted and an... A matrix encoding scheme for the steelmaking continuous casting( SCC) production scheduling( SCCPS) problem and the corresponding decoding method are proposed. Based on it,a cross entropy( CE) method is adopted and an improved cross entropy( ICE) algorithm is proposed to solve the SCCPS problem to minimize total power consumption. To describe the distribution of the solution space of the CE method,a probability model is built and used to generate individuals by sampling and a probability updating mechanism is introduced to trace the promising samples. For the ICE algorithm,some samples are generated by the heuristic rules for the shortest makespan due to the relation between the makespan and the total power consumption,which can reduce the search space greatly. The optimal sample in each iteration is retained through a retention mechanism to ensure that the historical optimal sample is not lost so as to improve the efficiency and global convergence. A local search procedure is carried out on a part of better samples so as to improve the local exploitation capability of the ICE algorithm and get a better result. The parameter setting is investigated by the Taguchi method of design-of-experiment. A number of simulation experiments are implemented to validate the effectiveness of the ICE algorithm in solving the SCCPS problem and also the superiority of the ICE algorithm is verified through the comparison with the standard cross entropy( SCE) algorithm. 展开更多
关键词 steelmaking continuous casting(SCC) production scheduling power consumption cross entropy(CE) PROBABILITY
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Effect of Interaction Intensity on Alignment and EFL Learners’ Oral Production in the ReadingSpeaking Integrated Continuation Task 被引量:4
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作者 Lin JIANG Yingxuan LUO Jianling ZHAN 《Chinese Journal of Applied Linguistics》 2021年第3期314-334,430,共22页
This study aims to uncover the relationship between interaction and alignment in a readingspeaking integrated continuation task, especially focusing on whether an increase in interaction intensity can lead to stronger... This study aims to uncover the relationship between interaction and alignment in a readingspeaking integrated continuation task, especially focusing on whether an increase in interaction intensity can lead to stronger alignment and further generate positive effects on L2 learning. To this end, 31 participants were asked to perform reading-speaking integrated continuation tasks under three different conditions featuring low, medium and high interaction intensity respectively. The results showed that 1) alignment existed in the reading-speaking integrated continuation task;2)increasing interaction intensity generated stronger alignment at both linguistic and situational levels;3) growing interaction intensity contributed to more coherent and accurate L2 oral production. These findings not only proved the workings of mind-body-world alignment, but also testified that increasing interaction intensity could bring about a stronger alignment effect(Wang,2010), which then contributed to better L2 oral performance. These findings confirm again the role of interaction in L2 learning and suggest that alignment could possibly be a mediating factor that links interaction and L2 development. Pedagogical implications for teaching and learning L2 speaking are discussed. 展开更多
关键词 the continuation task ALIGNMENT interaction intensity oral production
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Structure of continuous matrix product operator for transverse field Ising model:An analytic and numerical study
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作者 Yueshui Zhang Lei Wang 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第11期121-142,共22页
We study the structure of the continuous matrix product operator(cMPO)^([1]) for the transverse field Ising model(TFIM).We prove TFIM’s cMPO is solvable and has the form T=e^(-1/2H_(F)).H_(F) is a non-local free ferm... We study the structure of the continuous matrix product operator(cMPO)^([1]) for the transverse field Ising model(TFIM).We prove TFIM’s cMPO is solvable and has the form T=e^(-1/2H_(F)).H_(F) is a non-local free fermionic Hamiltonian on a ring with circumferenceβ,whose ground state is gapped and non-degenerate even at the critical point.The full spectrum of H_(F) is determined analytically.At the critical point,our results verify the state–operator-correspondence^([2]) in the conformal field theory(CFT).We also design a numerical algorithm based on Bloch state ansatz to calculate the lowlying excited states of general(Hermitian)cMPO.Our numerical calculations coincide with the analytic results of TFIM.In the end,we give a short discussion about the entanglement entropy of cMPO’s ground state. 展开更多
关键词 continuous matrix product operator transverse field Ising model state-operator-correspondence
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Alumina Carbon Refractory Products for Continuous Casting
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作者 Zhang Xiaohui 《China's Refractories》 CAS 2008年第4期29-31,共3页
1 Scope :This standard specifies the classification, technical requirements, test methods, inspection rules, packing, marking, transportation, storage and quality certificate of alumina carbon refractory products fo... 1 Scope :This standard specifies the classification, technical requirements, test methods, inspection rules, packing, marking, transportation, storage and quality certificate of alumina carbon refractory products for continuous casting. 展开更多
关键词 Alumina Carbon Refractory products for continuous Casting
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Drought and Flood Analysis and Impact on Food Production in Fushun 被引量:3
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作者 李金义 银燕 +1 位作者 张影 迟贵富 《Meteorological and Environmental Research》 CAS 2010年第6期33-35,38,共4页
Based on monthly precipitation data during 1961-2008 in 50 stations in Fushun,drought and flood indicators of three counties were calculated with Z index method. The geographical and seasonal distribution characterist... Based on monthly precipitation data during 1961-2008 in 50 stations in Fushun,drought and flood indicators of three counties were calculated with Z index method. The geographical and seasonal distribution characteristics of Fushun were analyzed,and so was the impact of droughts and floods on food production. It shows that,since 1961,there are 7 poor harvest years in Fushun,with quadrennial caused by continuous seasonal floods or droughts,two years by year drought,one year by summer flood. 展开更多
关键词 Drought and flood indicators Food production Z index Droughts or floods in continuous seasons China
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Morphology and Precipitation Kinetics of MnS in Low-Carbon Steel During Thin Slab Continuous Casting Process 被引量:11
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作者 YU Hao KANG Yong-lin +1 位作者 ZHAO Zheng-zhi SUN Hao 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2006年第5期30-36,共7页
The morphology of manganese sulfide formed during thin slab continuous casting process in low-carbon steel produced by compact strip production (CSP) technique was investigated. Using transmission electron microscop... The morphology of manganese sulfide formed during thin slab continuous casting process in low-carbon steel produced by compact strip production (CSP) technique was investigated. Using transmission electron microscopy analysis, it was seen that a majority of manganese sulfides precipitated at austenite grain boundaries, the morphologies of which were spherical or close to the spherical shape and the size of MnS precipitates ranged from 30 nm to 100 nm. A mathematical model of the manganese sulfide precipitation in this process was developed based on classical nucleation theory. Under the given conditions, the starting and finishing precipitation temperatures of MnS in the continuous casting thin slab of the studied low-carbon steel are 1 189 ℃ and 1 171 ℃, respectively, and the average diameter of MnS precipitates is about 48 nm within this precipitation temperature range. The influences of chemical components and thermo-mechanical processing conditions on the precipitation behavior of MnS in the same process were also discussed. 展开更多
关键词 MORPHOLOGY thin slab continuous casting precipitation kinetics compact strip production TEM
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Anaerobic hydrogen production of molasses from mixed microbial communities immobilized by activated granular carbon 被引量:2
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作者 李永峰 赵倩 《化工进展》 EI CAS CSCD 北大核心 2012年第S1期384-392,共9页
Molasses wastewater was evaluated as substrate for biohydrogen production by anaerobic fermentation in a novel continuous mixed attached growth reactor ( CMAGR ) with aeration pretreated sludge attached onto granular ... Molasses wastewater was evaluated as substrate for biohydrogen production by anaerobic fermentation in a novel continuous mixed attached growth reactor ( CMAGR ) with aeration pretreated sludge attached onto granular activated carbon under continuous flow condition.It was indicated that the CMAGR system was operated at the conditions of influent COD of 2000~6000mg / L , hydraulic retention time ( HRT ) of 6hand temperature of 35 ℃ , when the pH value and oxidation-reduction potential ( ORP ) ranged from 4.16and-434 mV respectively , stable ethanol-type fermentation was formed with the sum of ethanol and acetate concentration ratio of 89.3%to the total liquid products after 40days operation.The H 2 content in biogas and chemical oxygen demand ( COD ) removal were estimated to be 46.6% and 13% , respectively.It was also investigated that the effects of organic loading rates ( OLRs ) on CMAGR hydrogen production system.It was found that hydrogen production yield increased from 3.72 mmol / hL to 12.51 mmol / hL as OLRs increased from 8 kg / m 3 d to 32 kg / m 3 d.The maximum hydrogen production rate of 12.51mmol / hL at a OLR of 32kg / m 3 d and the maximum hydrogen yield by substrate consumed was 130.57 mmol / mol happened at OLR of 16 kg / m 3 d.Greater pHs appeared to be favour to butyrate production and the maximum of 0.51mol / mol was obtained at pH of 4.14.However , ethanol / acetate ratio was greater than 1.1at pH fluctuated between 3.4 - 3.6and 4.1 - 4.4which indicated that these pHs were favour to ethanol type fermentation.Therefore , the continuous mixed attached growth reactor ( CMAGR ) could be a promising attached growth system for biohydrogen fermentation. 展开更多
关键词 BIOHYDROGEN production continuous MIXED ATTACHED growth reactor molasess WASTEWATER ACTIVATED granular carbon WASTEWATER treatment
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Hydrogen Production with High Evolution Rate and High Yield by Immobilized Cells of Hydrogen-producing Bacteria Strain B49 in a Column Reactor 被引量:6
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作者 任南琪 Wang Xiangjing +3 位作者 Xiang Wensheng Lin Ming Li Jianzheng Guo Wanqian 《High Technology Letters》 EI CAS 2002年第4期21-25,共5页
To improve the hydrogen evolution rate in continuous hydrogen production of a fermentative hydrogen-producing bacteria strain B49 (AF481148 in EMBL), 4% immobilized cells by polyvinyl alcohol-boric acid method, with t... To improve the hydrogen evolution rate in continuous hydrogen production of a fermentative hydrogen-producing bacteria strain B49 (AF481148 in EMBL), 4% immobilized cells by polyvinyl alcohol-boric acid method, with the addition of a small amount of calcium alginate in a column reactor obtain hydrogen yield of 2.31 mol H2/mol glucose and hydrogen evolution rate of 1435.4 ml/L culture&middoth respectively at medium retention time of 2 h with a medium containing l0 g glucose/L. As the cell density in gel beads is increased to 8%, hydrogen yield and hydrogen evolution rate for l0 g glucose/L are 2.34 mol H2/mol glucose and 2912.4 ml/L culture &middot h respectively at medium retention time of 1 h, and for molasses wastewater COD of 7505.9 mg/L hydrogen production potential of 205.6 ml/g COD and hydrogen evolution rate of 2057.7 ml/L culture&middoth at hydraulic retention time of 0.75 h are observed. In the continuous culture pH value keeps around 3.9 by self regulation. 展开更多
关键词 hydrogen-producing BACTERIA STRAIN B49 immobilized cells continuous hydrogen production
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ENTROPY PRODUCTION RATE OF THE MINIMAL DIFFUSION PROCESS 被引量:1
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作者 章复熹 钱敏 《Acta Mathematica Scientia》 SCIE CSCD 2007年第1期145-152,共8页
The entropy production rate of stationary minimal diffusion processes with smooth coefficients is calculated. As a byproduct, the continuity of paths of the minimal diffusion processes is discussed, and that the point... The entropy production rate of stationary minimal diffusion processes with smooth coefficients is calculated. As a byproduct, the continuity of paths of the minimal diffusion processes is discussed, and that the point at infinity is absorbing is proved. 展开更多
关键词 Minimal diffusion process entropy production rate continuous path
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Effect of Copper (II) Ions on Quality of Struvite Produced in Continuous Reaction Crystallization Process at the Magnesium Ions Excess 被引量:1
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作者 Nina Hutnik Boguslawa Wierzbowska +1 位作者 Krzysztof Piotrowski Andrzej Matynia 《Advances in Chemical Engineering and Science》 2013年第4期1-6,共6页
The research results concerning continuous removal of phosphate (V) ions from solutions containing 1.0 or 0.20 mass % of phosphate (V) ions and 0.2 or 0.5 mg/kg of copper (II) ions using magnesium and ammonium ions ad... The research results concerning continuous removal of phosphate (V) ions from solutions containing 1.0 or 0.20 mass % of phosphate (V) ions and 0.2 or 0.5 mg/kg of copper (II) ions using magnesium and ammonium ions addition are presented. Continuous reaction crystallization of struvite MgNH4PO4 × 6H2O ran both under stoichiometric conditions and at 20% excess of magnesium ions (pH 9, t 900 s). It was concluded, that presence of copper (II) ions in a process system influenced product quality moderately advantageously. Mean size of struvite crystals enlarged by ca. 6% only. Lower concentration of phosphate (V) ions and excess of magnesium ions caused, that products of ca. 9% - 13% larger crystal mean size (up to ca.40mm) were removed from the crystallizer. Presence of struvite crystals and copper (II) hydroxide were detected analytically in the products (Cu in a product varied from 6 to 90 mg/kg). Presence of copper (II) ions favored crystallization of struvite in the form of tubular crystals. 展开更多
关键词 Struvite Phosphate(V) IONS COPPER IONS continuous REACTION Crystallization DT MSMPR CRYSTALLIZER Crystal Size Distribution product QUALITY
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Slab Storage Calculation Method for Continuous Casting-Hot Rolling
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作者 PENGQi-chun LIUQing TIANNai-yuan 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2004年第1期33-36,共4页
Based on load-oriented manufacturing control theory,different combining modes and slab storage calculation method for continuous casting and hot rolling were discussed.The buffer capacity index of continuous casting-r... Based on load-oriented manufacturing control theory,different combining modes and slab storage calculation method for continuous casting and hot rolling were discussed.The buffer capacity index of continuous casting-rolling was introduced,and the reasonable slab storage under different combining modes was calculated with buffer capacity index of 120.00 hfor CCR,79.20 hfor HCR,19.68 hfor DHCR and 3.84 hfor DR.Thin slab is 1.20 h,and the strip is zero.Theory gist was provided for steel enterprise to decrease storage. 展开更多
关键词 continuous casting hot rolling production control SLAB STORAGE
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Control strategy and methods for continuous direct compression processes
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作者 Yasuhiro Suzuki Hirokazu Sugiyama +14 位作者 Manabu Kano Ryutaro Shimono Gosuke Shimada Ryoichi Furukawa Eichi Mano Keiichi Motoyama Tatsuo Koide Yasuhiro Matsui Kazuki Kurasaki Issei Takayama Shunin Hikage Noriko Katori Masahiko Kikuchi Hiroshi Sakai Yoshihiro Matsuda 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2021年第2期253-262,共10页
We presented a control strategy for tablet manufacturing processes based on continuous direct compression.The work was conducted by the experts of pharmaceutical companies,machine suppliers,academia,and regulatory aut... We presented a control strategy for tablet manufacturing processes based on continuous direct compression.The work was conducted by the experts of pharmaceutical companies,machine suppliers,academia,and regulatory authority in Japan.Among different items in the process,the component ratio and blended powder content were selected as the items requiring the control method specific to continuous manufacturing different from the conventional batch manufacturing.The control and management of the Loss in Weight(LIW)feeder were deemed the most important,and the Residence Time Distribution(RTD)model were regarded effective for setting the control range and for controlling of the LIW feeder.Based on these ideas,the concept of process control using RTD was summarized. 展开更多
关键词 continuous manufacturing Solid drug products Process control Residence time distribution Loss in weight feeder Regulatory science
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Analysis of Waste in the Production of Concrete Blocks---A Case Study in the Goias Industry
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作者 Tatiana Gondim do Amaral Weslley M. Cruz Jose R. Perim 《Journal of Civil Engineering and Architecture》 2015年第8期926-937,共12页
An ever more demanding consumer market and the need for companies to be more competitive have led organizations to try to eliminate waste. This research is a case study which presents a proposal for intervention in or... An ever more demanding consumer market and the need for companies to be more competitive have led organizations to try to eliminate waste. This research is a case study which presents a proposal for intervention in order to improve performance of a pre-cast concrete block factory in outer Goihnia. As a first step, waste in the production process was identified through analysis of data on time involved in each step of the process. Then, applying the concepts of lean production, a list of activities was drawn up with a view to eliminating non-value-added work, identifying waste, decreasing cycle time, streamlining the production process and increasing the flexibility and transparency of the process. From the results, it was possible to identify the sources of waste and provide management with information for strategic decisions about production. Finally, various suggestions were made with a view to eliminating or mitigating bottlenecks in the production process. 展开更多
关键词 Lean production WASTE concrete blocks continuous improvement.
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A Basic Method of Constructing Production Functions
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作者 Guo Yaohuang Wang Yaping Zhang Wel(School of Economics and Management,Soultwest Jiaotong University), Chengdu 610031,China 《Journal of Modern Transportation》 1995年第2期127-132,共6页
In this paper,a new basic method of constructing smooth production functions isgiven,and many ordinary production functions are drawn. It is obvious thatsome more production functions can be obtained from the method.
关键词 production function continuously differentiable function homogeneousfunction
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Research for the steelmaking and continuous-casting scheduling model algorithm and system
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作者 SUN Ling and XU Jian Information Department,Soft Management Group,Beijing 100041,China 《Baosteel Technical Research》 CAS 2010年第S1期98-,共1页
In this paper,a steelmaking and continuous-casting production scheduling model is established according to the practical background of the Shou Gang-Qian Gang steel enterprise and then an algorithm is designed to solv... In this paper,a steelmaking and continuous-casting production scheduling model is established according to the practical background of the Shou Gang-Qian Gang steel enterprise and then an algorithm is designed to solve it.A steelmaking and continuous casting production scheduling system is developed based on the optimization model and algorithm.This system combines the optimization model,algorithm and human experience together.By using the human-machine interaction functions,the operator can modify this scheduling with his experience in the form of GANTT graph to get a schedule with high quality. 展开更多
关键词 steelmaking and continuous-casting production scheduling system GANTT
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