供应链中物流及信息流管理

供应链管理使企业在变化的市场环境中有效地与其它企业合作 ,取得集体竞争优势。本文首先讨论了后勤学与供应链管理的定义和之间的关系。本文认为供应链管理的核心是物流与信息流的控制。物流控制决策主要包括操作层次的库存补充和运输路径规划 ,以及战略层次的设施地点规划。信息流管理跨越部门与企业的界限将相关的应用集成起来。动态联盟协调各企业内部的生产经营活动 ,战略性地决定物流与信息流的构形。

大城市内部商业环境满意度评价与消费区位决策研究-以北京市西城区和海淀区为例

Since 1990s, commercial conditions in China including commercial environment, retail types, scale of retail enterprises, spatial structure of retail and shopping decision making factors have changed. In order to keep up with these changes, commercial geography should set up new perspectives, theories and methods to analyze its internal mechanism and changing rules, and thus provide reasonable and practical scientific basis to commercial planning, location decision of retail enterprises and commercial environment construction. Taking Xicheng and Haidian District of Beijing as research case, which is a sector region from city center to rural region, this paper selects 12 commercial centers as most important study objects of this sector. This paper mainly makes use of the methods of Modeling, Pearson Bivaiiate Correlations Analysis, Factor Analysis and Logit model. Based on 1300 questionnaires and fieldwork, this paper focuses on modeling of Consumer Satisfaction of Commercial Environment (CSCE), evaluation of commercial environment and driving factors of consumers' shopping location decision. Firstly, this paper discusses the development of commercial geography and commercial environment evaluation, the new characteristics and trends of commercial development in Beijing and physical commercial environment of Xicheng and Haidian District of Beijing from chapter 1 to chapter 4. Secondly, this paper summarizes characteristics of residents' shopping behavior in chapter 5. Thirdly, this paper sets up an evaluative model of CSCE, and analyzes consumer satisfaction indexes of commercial environment and their spatial features in chapter 6. Fourthly, this paper infers how residents' attributes and shopping behaviors affect their preferences of shopping location and what are residents' shopping location decisions and their influencing factors in chapter 7. Fifthly, this paper constructs a significant index model and a pyramidal framework of CSCE, and further analyzes the diversity and competitive advantage of commercial environment in chapter 8. Finally, some conclusions are drawn as follows: 1. Characteristics of residents' shopping behavior mostly embody residents' time distance preference, commodity consumption preference, shopping time distribution and shopping activity characteristics. The important factors that influence shopping location choice of residents are distance, transportation, commodity price, commodity types and commodity quality. However, the important factors, which influence shopping location re-choice of residents, are commodity price, commodity quality, commodity types and transportation. 2. CSCE indexes of 12 commercial centers show us significant spatial characteristics, such as spatial differences of "Center-fringe region", spatial characteristics of axes, spatial diversity of ring roads and so on. 3. Influencing factors including factor endowments, relative establishment factor and location and transportation factor of commercial environment are of importance for CSCE. 4. Logit model 1 indicates that shopping behavior of residents is significantly and positively related to working in high-tech companies, high income and by car and positively related to high school diploma, by bus and subway. 5. Logit model 2 indicates that residents' shopping location decision is significantly and positively related to leisure establishment and relative restaurant and entertainment establishment and negatively related to commercial location, commodity price, service quality, parking site. 6. The significant index model and the pyramidal framework of CSCE indicate competitive advantages are crucial to attractive capability of commercial center, and competitive weakness limits development of commercial centers, in particular the weakness of service quality and parking site now is the chief factors restricting development of commercial centers

Competitive protein adsorption studied with atomic force microscopy and imaging ellipsometry

The adsorption and competitive adsorption of collagen and bovine serum albumin (BSA) were directly visualized and quantified using atomic force microscopy (AFM) and imaging ellipsometry. Chemically modified silicon surfaces were used as hydrophilic and hydrophobic substrates. The results showed that collagen and BSA in single component solution adsorbed onto a hydrophobic surface two times more than that onto a hydrophilic surface. The competitive adsorption between collagen and BSA showed that serum albumin preferentially adsorbed onto a hydrophobic surface, while collagen on a hydrophilic surface. In the binary solution of BSA (1 mg/ml BSA) and collagen (0.1 mg/ml), nearly 100% of the protein adsorbed onto the hydrophobic surface was BSA, but on the hydrophilic surface only about 6% was BSA. Surface affinity was the main factor controlling the competitive adsorption.

Competitive adsorption between bovine serum albumin and collagen observed by atomic force microscope

Atomic force microscopy (AFM) was used to study the competitive adsorption between bovine serum albumin (BSA) and type I collagen on hydrophilic and hydrophobic silicon wafers. BSA showed a grain shape and the type I collagen displayed fibril-like molecules with relatively homogeneous height and width, characterized with clear twisting (helical formation). These AFM images illustrated that quite a lot of type I collagen appeared in the adsorption layer on hydrophilic surface in a competitive adsorption state, but the adsorption of BSA was more preponderant than that of type I collagen on hydrophobic silicon wafer surface. The experiments showed that the influence of BSA on type I collagen adsorption on hydrophilic surface was less than that on hydrophobic surface.

Competitive adsorption of collagen and bovine serum albumin - effect of the surface wettability

The competitive adsorption of collagen and bovine serum albumin (BSA) on surfaces with varied wettability was investigated with imaging ellipsometry, and ellipsometry. Silane modified silicon surfaces were used as substrates. The results showed that surface wettability had an important effect on protein competitive adsorption. With the decrease of surface wettability, the adsorption of collagen from the mixture solution of collagen and BSA decreased, while the adsorption of BSA increased. (C) 2003 Elsevier B.V. All rights reserved.

Dual-wavelength competitive output in Nd:Y3Sc1.5Al3.5O12 ceramic disk laser

In this paper, we demonstrated a dual-wavelength competitive output in Nd:Y3SC1.5Al3.5O12 ceramic disk laser. Different dual-wavelength output behaviors for Nd:YSAG and Nd:YAG ceramic disk laser were investigated and discussed. By applying the energy transfer model, we suggested the reasonable explanation for this new phenomenon as the disordered replacing of Al3+ ions by Sc3+ ions. The main advantage of the dual-wavelength ceramic laser is the possibility to serve as the seed source to generate Terahertz radiation. (C) 2008 Elsevier B.V. All rights reserved.

Physiological advantages may contribute to successful invasion of the exotic Cyprinus carpio into the Xingyun Lake, China

Feeding and growth traits of Cyprinus carpio and Cyprinus pellegrini (both at age-0) were compared in three experiment, in an attempt to analyze potential causes for the displacement of the native C. pellegrini in the Xingyun Lake, Yuxi, Yunan, China. Experiment I was conducted in water which fluctuated between 15 and 20 degrees C. Experiment II and III were conducted in a laboratory and water temperature was maintained between 20 degrees C and 25 degrees C, respectively. Three common trends were noted for all three experiments: (1) feeding rate of C. carpio was lower than that of C. pellegrini, and this difference was found to be significant in experiment I; (2) growth rate of C. carpio was higher than C. pellegrini, and the difference was found to be significant in experiment II; (3) food conversion efficiency and energy retention efficiency for C. carpio were higher than those of C. pellegrini, and significant differences were noted in experiment I and II. Since the growth period for fish in the Xingyun Lake generally occurs when water temperatures are between 15 and 25 degrees C, it can be suggested that C. carpio has advantages over C. pellegrini in growth and food utilization efficiency, and lower food consumption than C. pellegrini. These physiological traits of C. carpio might allow this species to be more resistant to food shortage and predation, and may be partially responsible for the displacement of C. pellegrini by C. carpio.

Studies on advantages of heavy ions in radiotherapy compared with gamma-rays

Hepatoma and melanoma cells were exposed to C-12(6+) beams generated by HIRFL facility and gamma-rays and the cell response was studied by colony assays as well as the analysis of RBE of carbon ions was evolved. The survival curves of cells irradiated by heavy ions were different from those of cells irradiated by gamma-rays. And two kinds of cell showed the obvious discrepancy in response to the photon and ion irradiation. The results showed that heavy ions have special physical properties and mighty potency to kill cell in both single and fractional irradiation meanwhile it can kill tumor cells with high radioresistance more efficiently. When involved in clinical therapy, heavy ions will enhance the therapy efficiency and decrease the suffering of patients because it can impair the repair for sublethal damage of cells which can lead to fewer irradiation fractions.

Study of competitive binding of enantiomers to protein by affinity capillary electrochromatography

Affinity capillary electrochromatography (CEC) with zonal elution method was used to probe the competitive interactions of enantiomers with protein. In this approach, a known concentration of a competing agent is continuously applied to a CEC column with bovine serum albumin (BSA) physically adsorbed on SAX packing while injections of a small amount of analyte are made. The binding sites of solutes on the BSA molecule were determined by the changes in the retention factors of the solutes resulted from the addition of competitive agent. By using D- or L-tryptophan as competitive agents and D-, L-tryptophan and benzoin enantiomers as injected analytes showed that BSA molecule has a primary site to strongly bind L-tryptophan, but D-tryptophan dose not bind at this site; D- and L-tryptophan share a weak binding site on the BSA molecule. Benzoin enantiomers do not share any binding sites with either D- or L-tryptophan. Non-chiral compounds of trichloroacetic acid and n-hexanoic acid were applied as the competitive agents to study the binding of warfarin enantiomers to BSA, it was observed that trichloroacetic acid and n-hexanoic acid had a same binding site for warfarin enantiomers binding to BSA molecule. (C) 2002 Elsevier Science B.V. All rights reserved.

Kinetic characteristics of the interaction between morphine and its antibody by SPR competitive immunoassay

It is impossible for surface plasmon resonance to measure directly the binding kinetics between a low-molecular-weight analyte interacting and its immobilized binding partner. Solution competition method was applied to the kinetic study of the interaction between morphine and its antibody. The affinity constant between the antibody of morphine and morphine-BSA immobilized on the sensor chip was also obtained. The result showed that the affinity of polyclonal antibody is stronger than that of monoclonal antibody. And it also indicated that the protein combined with the analyte affected the binding of antibody to antigen.