我国土壤质量及其评价研究的进展

在阐述了土壤质量的内涵基础上,分析了土壤质量和土壤健康、土地质量及土壤服务功能的联系。重点对我国土壤质量的评价研究进行了回顾和概述,从指标体系的选取和评价方法入手,探讨了评价的发展过程,分析了我国土壤评价指标体系因子选择的范围,在论述了国际土壤质量最新进展的基础上,指出了生物学指标研究是需要加强的方向;同时着重分析了我国土壤质量评价方法研究的进展,对我国土壤质量评价的方法进行了概括,指出了空间化,过程化,应用化和综合化的发展方向,并讨论了我国土壤评价研究的方向和趋势。     

土壤质量的酶学指标研究

土壤质量日益衰退,寻找能够准确标示其变化的敏感指标非常重要。土壤酶几乎参与了土壤中全部的生物化学反应,与土壤中多种生态过程密切相关。土壤酶的敏感性、专一性和综合性等特点使其可以作为一个反映土壤质量的生物学指标。本文在概述了土壤酶作为土壤质量指标可行性的基础上,综述了土壤肥力质量、环境质量等的土壤酶活性和酶动力学指标的研究,并对今后相关研究提出了几点建议。     

以中国土壤系统分类为基础的土壤参比

为了土壤信息交流、知识共享 ,作者首先阐述了与世界土壤分类发展相伴随的中国土壤系统分类的发展 ,进而对中国土壤系统分类与美国土壤分类和WRB方案进行了参比 ,然后着重讨论了它与土壤发生分类之间的参比。今后拟建立土壤参比信息系统以实现计算机自动参比     

土壤胶膜的研究进展

土壤胶膜是土壤中普遍存在的形成物,其性质与整个土体有较大的变异和不同,对土壤的物质流和能量流、生产力和植物营养以及土壤质量等有重要影响。本文从土壤胶膜的成因、分类、微形态特征、物质组成及其对土壤性质的影响,土壤胶膜与土壤发生与分类、古气候等的关系,探讨了土壤胶膜的研究进展,并展望了以后可能的研究趋势。     

土壤光学遥感研究进展

土壤是一个时空连续的变异体,传统土壤参数测定与监测方法难以揭示土壤的时空间异质性规律;土壤光学遥感可以实现土壤主要参数的快速、宏观测定。本文综合评述了土壤不同理化参数(有机质、土壤水分、矿物组成、土壤质地、土壤结皮)在光学波段的光谱特征与遥感反演,光学遥感在土壤分类与制图方面的应用;分析了土壤线的各种影响因素(外部因素及相关土壤理化参数),以及土壤线对植被指数定量监测植被状况的重要性;归纳了土壤光学遥感存在问题与发展趋势。     

秸秆深层覆盖对土壤水盐运移及小麦生长的影响

通过对秸秆不同覆盖方式的土柱模拟实验研究表明,秸秆深层覆盖在土壤中形成了一个毛细管障碍层,破坏了土壤毛细管的连续性,明显降低深层土壤水分蒸发,减少了深层土壤盐分向表层的运移;秸秆表层覆盖使土表与空气的接触面变小,利于土壤保水。深层秸秆结合表层秸秆覆盖对土壤的保水效果最好,而且抑制盐分的土壤表聚,减轻土壤盐分对作物生长的胁迫,降低土壤耕层的返盐,保证了作物正常生长。     

卫星遥感反演土壤有机质研究进展

土壤有机质是评价土壤质量的关键指标,了解土壤有机质含量及其空间分布,对实现土壤养分精准管理、促进农业可持续发展具有重要意义。近年来,遥感技术的迅猛发展为土壤属性定量化研究提供了丰富的数据源,卫星遥感反演土壤有机质逐渐吸引了更多的关注。文章针对土壤有机质反演的相关研究,阐述了土壤遥感及传感器发展历程、土壤有机质遥感反演机理;系统归纳了直接法、间接法以及实测高光谱与卫星遥感相结合3种反演方法的发展现状;将不同研究方法的优势及不足进行对比,并详细分析制约土壤有机质反演精度的关键因素,最后对卫星遥感反演土壤有机质的发展趋势进行展望。     

缓释型保水剂对土壤物理性状作用及油菜增产效果的研究

田间小区试验对施用缓释型保水剂、保水剂、常规肥料下土壤物理性状及油菜生长进行了研究。结果表明,缓释型保水剂为植株提供适宜的水分条件,促进了作物生长,油菜产量增加;缓释型保水剂具有保水和持水性能,提高了土壤水分含量,同时改善了土壤物理性状,降低土壤容重,使土壤孔隙数量增加,提高了土壤总孔隙度,尤其增加了非毛管孔隙度,增强了土壤通气性能;缓释型保水剂增加了土壤中大于0.25mm团聚体的数量,从而提高了土壤通气性,同时也增加了土壤中2mm以上的团聚体数量,提高了土壤的抗蚀性。     

施肥对旱地土壤供水特征的影响

陕西渭北旱塬土壤剖面中不同土层土壤的供水能力不同,呈现出“波“状分布.施肥处理均表现为“低-高-低-高“形,CK在小于12.5%含水量时为“高-低-高-低“状,大于12.5%含水量时为“低-高-低-高“状.土壤剖面中有一水势最低的土层,该土层有随施肥量增加而下移的趋势,对旱农区有限水分的吸收和保持有重要作用,土壤剖面中不同土层土壤供水能力的“锯齿“状分布也很好地发挥了这种作用.施肥提高了土壤水势,降低了土壤的水容比,增强了土壤的供水能力,从而提高了土壤对干旱的适应性和抵抗力,土壤比水容量更好地反映了土壤的保水性能,而土壤水势和土壤水容比则更好地反映了土壤的供水性能,即土壤水对植物的有效性.     

盐分对土壤锰释放的影响

盐分能诱导土壤锰的释放.Na+和Ca2+的离子交换作用促进了土壤锰向水溶液中释放,提高了土壤锰的有效性;同时,盐分降低了土壤的pH值,并使土壤氧化还原电位发生变化,引起土壤中锰形态间的转化.NO3-离子对氧化还原电位影响显著,硝酸盐处理土壤中易还原态锰含量显著增加.     

Consumers’ post-adoption behaviour towards Internet banking: empirical evidence from Australia

This study sets out to investigate the factors that influence Australian consumers’ post-adoption behaviour towards Internet banking. By integrating the research streams of technology adoption, diffusion of innovations and continuance theory of information systems, technology factors, channel factors, social factors and value-for-money factors were hypothesised to exert an impact on consumers’ post-adoption behaviour towards Internet banking. Data were gathered from 372 Internet banking users through a cross-sectional mall intercept survey. The data were analysed using Partial Least Squares path modelling. The results show that technology factors, channel factors and value-for-money factors partially influence consumers’ post-adoption behaviour towards Internet banking. Social factors were found to be non-significant. The practical implications for retail bank managers in formulating effective service delivery channel management strategies were outlined. The practical, theoretical and methodological implications of the study were discussed, and limitations and avenues for future research were presented.     

Development of a usability evaluation framework with quality function deployment: From customer sensibility to product design

The aim of this research was to develop a usability evaluation model based on customer sensation using quality function deployment (QFD), which evaluates the relationship between consumer sensation and usability among the physical design factors of dishwashers. Four aspects of the evaluation model were analyzed with QFD: overall sensation factors, detail sensation factors, usability evaluation factors, and physical design factors of products in 3 sequential processes. The sensation evaluation factors and the usability evaluation factors were created from the results of the sensation and usability tests. Moreover, experts and manufacturers were involved in selecting the physical design factors. With the evaluation model using these 4 aspects, physical design factors influencing user sensation were generated. These factors were Label Icon, Rack Size, Shape of Knob, and LCD size. In addition, the degree of influences was tested and design guidelines derived from the final physical design factors were generated. © 2009 Wiley Periodicals, Inc.     

Comparison of logistic regression model and classification tree: An application to postpartum depression data

In this study, it is aimed that comparing logistic regression model with classification tree method in determining social-demographic risk factors which have effected depression status of 1447 women in separate postpartum periods. In determination of risk factors, data obtained from prevalence study of postpartum depression were used. Cut-off value of postpartum depression scores that calculated was taken as 13. Social and demographic risk factors were brought up by helping of the classification tree and logistic regression model. According to optimal classification tree total of six risk factors were determined, but in logistic regression model 3 of their effect were found significantly. In addition, during the relations among risk factors in tree structure were being evaluated, in logistic regression model corrected main effects belong to risk factors were calculated. In spite of, classification success of maximal tree was found better than both optimal tree and logistic regression model, it is seen that using this tree structure in practice is very difficult. But we say that the logistic regression model and optimal tree had the lower sensitivity, possibly due to the fact that numbers of the individuals in both two groups were not equal and clinical risk factors were not considered in this study. Classification tree method gives more information with detail on diagnosis by evaluating a lot of risk factors together than logistic regression model. But making correct selection through constructed tree structures is very important to increase the success of results and to reach information which can provide appropriate explanations.     

The influence of climatic factors on non-specific back and neck-shoulder disease

An epidemiological study was carried out to explore the relationship between climatic factors and non-specific low-back and neck-shoulder symptoms in working populations. In a review of published literature, 27 studies were found which related climatic factors to musculoskeletal symptoms, but none of these studies specifically addressed the subject. It can be concluded that a relationship between climatic factors and musculoskeletal symptoms is considered at least plausible by both researchers, workers and patients, but that the epidemiological evidence appearing from literature is very weak. Questionnaire data which were collected on musculoskeletal symptoms, workload and perceptions of climatic conditions of 2030 workers in 24 different occupations were analysed multivariately. About one-quarter of the workers related symptoms of the low back and neck-shoulders to climatic factors. They perceived climatic factors in most cases as aggravating factors for their symptoms. No seasonal influence on prevalence rates was reported. For low-back and neck-shoulder symptoms and for sick leave due to neck-shoulder symptoms, an association was found with climatic factors, and in particular with respect to draughts in relation to neck-shoulder symptoms. In addition, neck-shoulder symptoms were negatively related to frequent outdoor work. The findings suggest a relationship between climatic factors and musculoskeletal symptoms and call for further detailed investigations.     

Risk factors associated with online game addiction: A hierarchical model

Online gaming addiction has been increasingly recognized as a mental disorder. However, the predictive factors that lead to online gaming addiction are not well established. The aim of this study was to identify factors that may influence the development of online gaming addiction. A total of 263 patients with problematic online gaming addiction (255 males (97%) and 8 females (3%), age: mean = 20.4 ± 5.8 years) and153 healthy comparison subjects (118 males (77%) and 35 females (23%), age: 21.2 ± 5.5 years, range) were recruited for participation in the current study. Hierarchical logistic regression analyses among each set of variables were conducted. Individual factors (sex and age), cognitive factors (IQ and perseverative errors), psychopathological conditions (ADHD, depression, anxiety, and impulsivity), and social interaction factors (family environment, social anxiety, and self-esteem) were evaluated in a stepwise fashion. All four factors were associated with online gaming addiction, with psychopathological conditions being the strongest risk factors for the addiction. Individual factors, psychological factors, and social interactions were associated with the development of pure online gaming addiction. As before, psychological factors (attention, mood, anxiety and impulsivity) were the strongest risk factors for online gaming addiction in patients with pure online gaming addiction. Psychopathologies, including ADHD and depression, were the strongest factors associated with the development of online gaming addiction in individuals.     

Requirements Determination: An Information Systems Specialist Perspective of Process Quality

An empirical study was performed to identify, elucidate and judge factors that affect the quality of the information requirements determination process. These quality factors were determined using a series of nominal group processes involving information systems specialists from various organisations and projects. The results indicate that there exists a set of factors that IS specialists from different organisations and with different systems experience agree upon as being critical to ensuring the quality of the requirements determination process, and that these factors appear to fall into six categories: IS specialist factors, user factors, project team factors, project factors, application factors and environmental/organisational factors.     

辽宁省种植冬麦的农业气候指标研究

本文通过对可能影响冬麦生育过程的若干因子的分析，筛选出４个主要气候因子，作为辽宁省种植冬麦的农业气候指标。这４个农业气候指标是：越冬前活动积温为４２０～５４０℃，越冬前降水１２０～１７０ｍｍ，抽穗到成熟期降水 １１０～ １５０ｍｍ，越冬期可耐一 ８００ ℃负积温及一２４～一２６℃的极端最低气温。由此，以农业气候相似论为依据，可以实现以沈阳为中心的辽宁省部分地区冬麦北移种植的构想。     

E-Commerce Infrastructure Success Factors for Small Companies in Developing Economies

This paper looks into the key infrastructure factors affecting the success of small companies in developing economies that are establishing B2B e-commerce ventures. The factors were identified through a literature review and a pilot study carried out in two organizations. The results of the pilot study and literature review reveal five factors that contribute to the success of B2B e-commerce. These factors were later assessed for importance using a survey. The outcome of our analysis reveals that workers' skills, client interface, and technical infrastructure are the most important factors to the success of a B2B e-commerce relationship.     

The influence of climatic factors on non-specific back and neck-shoulder disease

An epidemiological study was carried out to explore the relationship between climatic factors and non-specific low-back and neck-shoulder symptoms in working populations. In a review of published literature, 27 studies were found which related climatic factors to musculoskeletal symptoms, but none of these studies specifically addressed the subject. It can be concluded that a relationship between climatic factors and musculoskeletal symptoms is considered at least plausible by both researchers, workers and patients, but that the epidemiological evidence appearing from literature is very weak. Questionnaire data which were collected on musculoskeletal symptoms, workload and perceptions of climatic conditions of 2030 workers in 24 different occupations were analysed multi-variately. About one-quarter of the workers related symptoms of the low back and neck-shoulders to climatic factors. They perceived climatic factors in most cases as aggravating factors for their symptoms. No seasonal influence on prevalence rates was reported. For low-back and neck-shoulder symptoms and for sick leave due to neck-shoulder symptoms, an association was found with climatic factors, and in particular with respect to draughts in relation to neck-shoulder symptoms. In addition, neck-shoulder symptoms were negatively related to frequent outdoor work. The findings suggest a relationship between climatic factors and musculoskeletal symptoms and call for further detailed investigations.     

An assessment system for rating scientific journals in the field of ergonomics and human factors

A method for selecting and rating scientific and professional journals representing the discipline of ergonomics and human factors is proposed. The method is based upon the journal list, impact factors and citations provided by the Institute of Scientific Information (ISI), and the journal list published in the Ergonomics Abstracts. Three groups of journals were distinguished. The 'ergonomics journals' focus exclusively on ergonomics and human factors. The 'related journals' focus on other disciplines than ergonomics and human factors, but regularly publish ergonomics/human factors papers. The 'basic journals' focus on other technical, medical or social sciences than ergonomics, but are important for the development of ergonomics/human factors. Journal quality was rated using a maximum of four categories: top quality (A-level), high quality (B-level), good quality (C-level)) and professional (P-level). The above methods were applied to develop the Ergonomics Journal List 2004. A total of 25 'ergonomics journals', 58 'related journals' and 142 'basic journals' were classified.