多目标进化算法中基于聚集距离调整的分布性保持方法

在经典的非支配排序遗传算法中,基于聚集距离的种群维护策略并不能很好地保持解集的分布性。提出一种改进的基于聚集距离调整的分布性维护策略,根据邻近个体的聚集距离大小关系,保留分布较好的个体。与经典算法NSGA-Ⅱ,PESA-Ⅱ和小生境方法进行比较,实验结果表明,提出的分布性维护策略能较大程度提高分布性,并保持较好的收敛性。     

Determinants of Mortgage Protection Insurance Take-up

The aim of this paper is to identify the factors which affect the take-up of Mortgage Payment Protection Insurance (MPPI), to estimate the sensitivity of take-up to changes in determinants. The paper finds that: (1) MPPI premiums have a negative but marginal effect on take-up; (2) the probability of being unemployed has a positive effect: a 10 per cent rise in the probability resulting in a 3 per cent increase in take-up; (3) the local male unemployment rate has a positive effect on take-up (around 1 per cent increase in take-up for every 10 per cent rise in the male unemployment rate); (4) there is likely to be a pro-cyclical element in the take-up rate, but the variation is substantially damped compared with the volatility of the unemployment cycle; and (5) ISMI cover was found to have a negligible negative effect on take-up (a 10 per cent fall in ISMI would cause a 0.3 per cent rise in take-up), an effect that could not be statistically distinguished from zero.     

Risk factors for mold in housing: a national survey

A national random telephone survey was undertaken to determine the prevalence of reported mold in New Zealand houses and the risk factors for it. A total of 613 households provided responses. Mold in one or more rooms was reported by 35.1% of respondents in the sample. House design and construction factors that were independently associated with reported mold in the multivariate analysis included: poorer house condition, older house age (>22 years), relative lack of sun exposure, and having no insulation (e.g. for poorer house condition: odds ratio=1.97, 95% CI=1.25, 3.11). Univariate analyses also showed increased risk associated with high locality rainfall, and living in the most northern part of the country. The number of residents was significantly associated with reported mold in the multivariate analysis as were various behaviors in the univariate analysis (i.e. frequency of baths, showering and clothes washing). The high prevalence of unflued gas heating (32.9%) found in this sample is of potential concern given the potential respiratory hazards. Although this survey has a number of limitations, it does suggest that there are a number of potentially modifiable risk factors for mold that could be reduced by a range of policy responses. PRACTICAL IMPLICATIONS: While further research is desirable, the available evidence associated with the health and other adverse impacts of both mold and dampness would favor additional policy responses by government. These could include changes to regulations around housing design including house position, access to sunlight, and level of insulation. The extension of low interest loans for insulation or subsidized installation can help to increase its level of use. Restrictions on the sales of unflued gas heaters could also be considered. A mass media campaign could also be used to inform the population of the readily modifiable risk factors for mold growth and dampness.     

Improvement of the catalytic performance of immobilized penicillin acylase through assembly of macromolecular reagents in nanopore to create a crowding environment

Macromolecular reagents were co-assembled with penicillin acylase (PA) and immobilized in mesocellular siliceous foams (MCFs) to resemble living cells. Types and concentrations of macromolecules were studied. The catalytic characteristic and stability of PA preparations were also investigated. PA assembled with dextran 10 k in MCFs showed maximum specific activity, 1.32-fold of that of the solely immobilized PA. The optimum pH of dextran and BSA derivatives shifted to neutrality, and the optimum temperature increased by 10 °C. Also, Km of BSA derivative of PA declined 56.7% compared to solely immobilized PA, while the Kcat/Km of PA assembled with BSA was enhanced to 147%. After incubation at 50 °C for 6 h, residual activity of PA assembled with BSA exhibited 53.0%. The ficoll derivative showed 82.8% of its initial activity at 4 °C after 8-week storage. The results indicated that macromolecular reagents assembled with PA in MCFs could dramatically improve the catalytic performance and stability of immobilized enzyme.     

Design of circulation axes in densely used polyclinic waiting halls

The purpose of this article is to explore whether spatial definition can affect the perceptual evaluations of users in highly dense conditions. The particular spatial definition studied in this research was the relationship between circulation axes and seating areas of a waiting hall. In crowded public interiors, it is generally assumed that users feel less comfortable and less safe. As suggested in this work, the disturbance is much higher even where there are less-defined boundaries (where people pass through from different directions) and the space is more likely to be perceived negatively. To research this, a study was carried out in three waiting halls of a large polyclinic building: a clinic waiting hall, a pharmacy waiting hall, and an X-ray waiting hall, spatially designed different from each other. Results from 240 patients showed that the least identifiable waiting hall design was perceived the most negatively. The effect of gender on performance appraisal task was also examined. Compared to females, male users perceived the space more positively than female users.     

Perceived crowding in a café/restaurant with different seating densities

In this study, the impact on the perception of the density of seating elements used in a café/restaurant has been examined. Spatial factors, like the density of seating, were assumed to influence the perceived crowding and perception of a space. A two-stage study was carried out in a café/restaurant where a dense amount of seating elements was later changed to less dense. Each situation was tested by using atmospheric attributes through the use of bipolar scales. Results from 465 participants showed that when the seating elements were less dense, respondents answered more positively. The effect of gender on performance appraisal task was also examined. Compared to female users, male users were more favorable to both moderate and high-density conditions.     

Fast Parallel Identification of Multi-peaks in Function Optimization

A class of hybrid niching evolutionary algorithms （HNE） using clustering crowding and parallel local searching is proposed. By analyzing topology of fitness landscape and extending the space for searching similar individual, HNE determines the locality of search space more accurately, and decreases the replacement errors of crowding and suppressing genetic drift of the population. The integration of deterministic and probabilistic crowding increases the capacity of both parallel local hill-climbing and maintaining multiple subpopulations. Parallel local search based on simplex method over disjoint subpopulations greatly speeds up the convergence of the population towards various optima simultaneously. Real coded representation and Gaussian mutation improve the precision of the solutions founded. The experimental results optimizing various multimodal functions show that, the performances of HNE such as the number of effective peaks generated and maintained, average peak ratio, global optimum ratio and CPU time consumed are uniformly superior to those of genetic algorithms using the sharing and deterministic crowding method.     

EFFICIENT MULTI-OBJECTIVE EVOLUTIONARY ALGORITHM FOR JOB SHOP SCHEDULING＊

A new representation method is first presented based on priority rules.According to this method,each entry in the chromosome indicates that in the procedure of the Giffler and Thompson (GT) algorithm,the conflict occurring in the corresponding machine is resolved by the corresponding priority rule.Then crowding-measure multi-objective evolutionary algorithm (CMOEA) is designed, in which both archive maintenance and fitness assignment use crowding measure.Finally the comparisons between CMOEA and SPEA in solving 15 scheduling problems demonstrate that CMOEA is suitable to job shop scheduling.     

颜料对太阳热反射涂层热反射性能的影响

在对太阳热反射涂层反射原理分析的基础上,研究了颜料粒子的形状、颜料作积分数以及颜料的聚集状态对太阳热反射率的影响。