A basic study with feasibility of applying clean development mechanism to the transport projects

In the transport sector, few projects applied Clean Development Mechanism (CDM) or Joint Implementation (JI) projects. This study will examine the feasibility of applying CDM to the transport sector from viewpoints of validation of processes and funding. A number of greenhouse gas emission reduction projects, as well as traffic management project within existing transport infrastructures, can be implemented as CDM projects. New transport infrastructure projects can be validated by transportdemand forecasting and traffic simulation methods, though application of Life Cycle Assessment (LCA) and Intelligent Transport Systems (ITS) technologies. This revised version was published online in August 2006 with corrections to the Cover Date.     

Bayesian Modeling of Enteric Virus Density in Wastewater Using Left-Censored Data

Stochastic models are used to express pathogen density in environmental samples for performing microbial risk assessment with quantitative uncertainty. However, enteric virus density in water often falls below the quantification limit (non-detect) of the analytical methods employed, and it is always difficult to apply stochastic models to a dataset with a substantially high number of non-detects, i.e., left-censored data. We applied a Bayesian model that is able to model both the detected data (detects) and non-detects to simulated left-censored datasets of enteric virus density in wastewater. One hundred paired datasets were generated for each of the 39 combinations of a sample size and the number of detects, in which three sample sizes (12, 24, and 48) and the number of detects from 1 to 12, 24 and 48 were employed. The simulated observation data were assigned to one of two groups, i.e., detects and non-detects, by setting values on the limit of quantification to obtain the assumed number of detects for creating censored datasets. Then, the Bayesian model was applied to the censored datasets, and the estimated mean and standard deviation were compared to the true values by root mean square deviation. The difference between the true distribution and posterior predictive distribution was evaluated by Kullback–Leibler (KL) divergence, and it was found that the estimation accuracy was strongly affected by the number of detects. It is difficult to describe universal criteria to decide which level of accuracy is enough, but eight or more detects are required to accurately estimate the posterior predictive distributions when the sample size is 12, 24, or 48. The posterior predictive distribution of virus removal efficiency with a wastewater treatment unit process was obtained as the log ratio posterior distributions between the posterior predictive distributions of enteric viruses in untreated wastewater and treated wastewater. The KL divergence between the true distribution and posterior predictive distribution of virus removal efficiency also depends on the number of detects, and eight or more detects in a dataset of treated wastewater are required for its accurate estimation.     

道路交通事故信息文本预处理技术研究与实践

文本预处理是文本挖掘的关键一步,建立与信息相匹配的标准语义集合能缩短信息处理的时间,提高信息的提取率和识别精度。根据国家交通事故信息采集规范要求,从国家公共安全行业标准中抽取相关交通事故基本信息的标准词汇及代码,构建了一套含有12个属性项目、185个标准词汇的交通事故信息文本预处理用标准化语义集合,并将其应用于国家安全生产监督管理总局的事故查询系统,对系统中2004—2014年期间所收集的8 156件重大道路交通事故信息中的文本数据进行分析。结果表明:利用这套语义集合能更多地提取交通事故信息,可为准确捕捉交通事故特征和研究交通事故发生机理提供重要依据,也为开发交通事故自动信息识别系统创造了重要的条件。     

Evaluating the relative importance of intrinsic and extrinsic factors on the foraging activity of top predators: a case study on female little penguins

A complex interaction of biotic and abiotic factors influences animal foraging activity. It is often difficult to understand which factors may affect animals’ foraging and how it is affected. For instance, whereas the effect of sexual dimorphism on foraging activity has been reported in several species, little is known of the complex interactions between variables acting at a finer scale, e.g. the variability of body mass within a sex. Evaluating the importance of these finer scale factors is also essential to the understanding of foraging behaviour. We propose here a simple approach by applying principal component analysis (PCA) in a novel way to examine relationships between biotic and abiotic factors affecting foraging behaviour of top predators. We studied female little penguins (Eudyptula minor) of known age, carrying miniature accelerometers during the guard stage of breeding. Surprisingly, the body mass of the females did not influence any of the foraging parameters, but females foraging later in the breeding season dived shallower and more often, showing a strong correlation with laying date. Similarly, the diving effort of females was greater with increasing chick age within the same breeding stage. These results indicate that for female little penguin, the relationship between changes in prey availability and hunting effort can change at a fine scale, within a breeding stage. Therefore, any analysis of little penguin foraging behaviour during breeding should consider the timing in relation to the breeding season. We encourage researchers to develop the use of this PCA approach as it could help clarify the complexity of the underlying mechanisms determining foraging activity and we propose that it should be used as a first step of foraging behaviour analysis, before examining a particular relationship.     

Studies on automated survey system of environmental chemicals by gas chromatography-mass spectrometry-computer III. Construction of an automated survey system and its application

An automated survey system on the chemicals in environments by a gas chromatography-mass spectrometry-computer system has been constructed of Three Dimensional Mass Chromatography, Modified Probability Based Matching method, and Self Training Interpretive and Retrieval method. And it was applied to analyze environmental materials, with interesting results.     

Heavy metals removal from aqueous solution using carbonaceous K_2S-impregnated adsorbent

A novel carbonaceous adsorbent for heavy metal removal was prepared from raw coal by one-step simple sulfur impregnation using K_2S. Raw coal was mixed with K_2S powder and then heated at 800℃ for 30 min in nitrogen to produce K_2S char. The sulfur content and form in K_2S char were determined, and the ability of K_2S char to adsorb Zn~(2+), Cd~(2+) and Pb~(2+) was examined. The K_2S impregnation was effective at impregnating sulfur into coal, especially in the form of elemental, thiophenic and sulfatic sulfur. The sulfur content of K_2S char was higher than those of raw coal and pyrolysis char. The Zn~(2+) removal in 2.4 mmol/L of Zn~(2+) solution by K_2S char was higher than raw coal with the removal rate of 100%. K_2S char adsorbed Pb~(2+) and Cd~(2+) in 24 mmol/L of Pb~(2+) and Cd~(2+) solution with the removal rate of 97 % and 35 %, respectively. The elution extents of adsorbed Pb~(2+) and Cd~(2+) were zero in distilled water and 27% in 0.1 mol/L HCl solution. These results indicated that an effective adsorbent for heavy metal ions was prepared from coal using K_2S sulfur impregnation, and that the adsorbed metals were strongly retained in K_2S char.     

Relationship between the growth and survival of larval Pacific bluefin tuna, Thunnus orientalis

We tested the hypothesis that a large body size and rapid growth rate affect the survival of larval Pacific bluefin tuna, Thunnus orientalis (PBT), and analyzed larval growth in relation to environmental conditions. Seven high density larval patches of PBT were tracked with reference buoys in the northwestern Pacific Ocean for 28–171 h in May–June from 2004 to 2008. The otolith radii and daily growth rates of the survivor larvae (collected on later tracking days of each tracking session) tended to be larger and more rapid, respectively, than those of original larvae (collected on earlier tracking days). A large body size was found to positively affect the survival of larval PBT, as did a rapid growth rate, even at an early larval stage (7 days after hatching). Generalized linear modeling showed that the otolith radius was influenced positively by the sea temperature, stratification parameter and food density, while the growth rate was influenced positively by the sea temperature and food density.     

Toxic elements in well water from Malaysia

Toxic elements present in well water that is used for drinking pose a threat to the human health in many countries. However, there are few reports on the toxic elements in well water in Malaysia. Since a native doctor informed us about the increasing number of patients with depigmented skin (vitiligo) in Rosob Village, Sabah State, Malaysia, the origin of diseases associated with well water was suspected. Thus, the concentrations of 15 toxic elements in 52 well water samples from Rosob (n = 21), and the control areas of Pitas (n = 8) and Telaga (n = 23) within the same state were measured. No toxic elements with levels exceeding that of the WHO health-based guidelines were detected in the well water samples from Pitas and Telaga. On the other hand, the concentration levels of arsenic (As), uranium (U), and manganese (Mn), independently found in 19% (4/21), 4.8% (1/21), and 19% (4/21), respectively, of the well water samples from Rosob, exceeded the levels given in the WHO health-based guidelines. In the well water samples from Rosob, the average concentration of Mn was found to be higher and its maximum value with levels up to 10-fold higher, respectively, than the value in the WHO health-based guidelines. Significant correlations between Mn and As and between Mn and U were noted. Thus, for the first time, the results of this pilot study showed that the levels of the toxic elements in 42.9% (9/21) of well water samples from Rosob in Malaysia were higher than the values in WHO health-based guidelines indicating the need for further studies.