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

A novel technique for predicting ionizing radiation effects of commercial MOS devices

A nondestructive selection technique for predicting ionizing radiation effects of commercial metal-oxide-semiconductor (MOS) devices has been put forward. The basic principle and application details of this technique have been discussed. Practical application for the 54HC04 and 54HC08 circuits has shown that the predicted radiation-sensitive parameters such as threshold voltage, static power supply current and radiation failure total dose are consistent with the experimental results obtained only by measuring original electrical parameters. It is important and necessary to choose suitable information parameters. This novel technique can be used for initial radiation selection of some commercial MOS devices.

Effect of gamma-radiation on the thermal and mechanical properties of a commercial poly(butylene adipate-co-terephthalate)

BACKGROUND: Poly(butylene adipate-co-terephthalate) (PBAT) has attracted wide interest as a biodegradable polymer. However, its use is restricted in certain applications due to its low melting point.RESULTS: PBAT was treated using gamma-radiation. The radiation features were analyzed using Soxhlet extraction, and the ratio of chain scission and crosslinking and gelation dose were determined using the classical Charlesby-Pinner equation. The results showed that PBAT is a radiation-crosslinkable polymer. The degree of crosslinking increased with increasing radiation dose; the relation between sol fraction and dose followed the Charlesby-Pinner equation. Differential scanning calorimetry analyses showed that the melting temperature (T-m) and the heat of fusion (Delta H-m) of PBAT exhibited almost no change in the first scan. The second scan, however, showed a decrease in T-m and Delta H-m. The glass transition temperature of irradiated PBAT increased with increasing radiation dose.

Cultivation of the intertidal brown alga Hizikia fusiformis (Harvey) Okamura: mass production of zygote-derived seedlings under commercial cultivation conditions, a case study experience

Mariculture of the brown alga Hizikia fusiformis (Harvey) Okamura as an export-oriented human food has been there more for than 20 years in China. It is now one of the five major farmed algal species along the Chinese coast. Stable and sufficient supply of young seedlings for scaling up the cultivation has been a problem throughout the farming history of this species due to the unique dioecious life cycle and relatively short time window of sexual reproduction in nature. These two factors led to a practical difficulty in obtaining zygotes at identical developmental stage in viable amounts for seedling production. A key solution to this problem is to control the synchronization of the receptacle development and to realize the simultaneous discharge of male and female gametes, such that the fertilization rate could be greatly enhanced. Focusing on one of the farmed populations in this report, we present our results on mass production of seedlings using the synchronization technique on a large scale performed in 2007. Totally 5.5 hundred million embryos were obtained from 100 kg female sporophytes. The seedlings were raised up to 3.5 mm in length in greenhouse tanks over a month and were further grown in open sea for over 3 months at two experimental sites. The success of mass production of seedlings in this alga helped to lay the basis for future trials in other species in the genus of Sargassum that have identical life cycle.