Sampling from spatial databases

This paper deals with techniques for obtaining random point samples from spatial databases. We seek random points from a continuous domain (usually ²) which satisfy a spatial predicate that is represented in the database as a collection of polygons. Several applications of spatial sampling (e.g. environmental monitoring, agronomy, forestry, etc) are described. Sampling problems are characterized in terms of two key parameters: coverage (selectivity), and expected stabbing number (overlap). We discuss two fundamental approaches to sampling with spatial predicates, depending on whether we sample first or evaluate the predicate first. The approaches are described in the context of both quadtrees and R-trees, detailing the sample first, acceptance/rejection tree, and partial area tree algorithms. A sequential algorithm, the one-pass spatial reservoir algorithm is also described. The relative performance of the various sampling algorithms is compared and choice of preferred algorithms is suggested. We conclude with a short discussion of possible extensions.     

獭兔养殖综合技术研究

对獭兔的适应性、饲养管理、疾病防治、产品加工等养殖综合技术进行了研究,提出了獭兔的“三改、两杯、两早一分和两选两适”规范化饲养管理制度和疾病综合防治技术措施,探索出了优质獭兔毛皮和“富钙兔肉脯”的加工工艺以及獭兔良种推广的有效途径。     

空间OLAP 技术研究

针对决策支持系统中空间数据可视化应用趋势,研究基于空间数据仓库的一种决策分析 工具———在线分析处理,通过改进空间数据立方体的物化视图选择方法,并进行了实例分析, 验证该方法的有效性和优越性,更好地解决空间OLAP 响应时间延迟问题. 进而扩展空间OLAP 应用模型和模式,实现更加完备、灵活的空间OLAP 操作功能.     

销售商的努力影响需求变化的供应链的合约

本文首先重新考察报童模型,认识设计使供应链达到合作的合约的内在机制。在此基础上,提出一个设计供应链合约的一般模型,然后利用此模型分析在销售商的努力影响需求变化的情形下使供应链达到合作的合约的设计框架,同时提出一个在销售商的努力影响需求变化的情形下使供应链达到合作的合约。     

Agreement and discrepancy between children,parents, and social workers on school‐based effort avoidance in child welfare services

A multiperspective approach is beneficial for obtaining reliable and multifaceted pictures of child behaviour problems. The goal of the present study is to examine interrater agreement on school‐based effort avoidance between children receiving child welfare services, parents, and social workers. Given previous findings, interrater agreement is expected to be low. Self‐reported data on school‐based effort avoidance were gathered for children and adolescents in child welfare services. Additionally, social workers (using the Teacher‐Report Checklist for social and learning behaviour) and parents (using the parallel version of the self‐rating questionnaire on school‐based effort avoidance) were asked to complete an external assessment tool to compare children's perspectives with the ratings of significant adults. The results confirmed significant discrepancies between parents' and children's ratings on effort avoidance tendencies. Furthermore, there were only small to moderate correlations between children's self‐ratings and the adults' assessments; however, the consensus between adults was higher than the interrater agreement between children and social workers. Discrepancies in ratings from multiple informants underline the importance of integrating multiple perspectives, especially children's perspectives, in the diagnostic process in order to plan and adapt appropriate care and treatment.     

Does Iconicity in Pictographs Matter? The Influence of Iconicity and Numeracy on Information Processing,Decision Making,and Liking in an Eye‐Tracking Study

Researchers recommend the use of pictographs in medical risk communication to improve people's risk comprehension and decision making. However, it is not yet clear whether the iconicity used in pictographs to convey risk information influences individuals’ information processing and comprehension. In an eye‐tracking experiment with participants from the general population (N = 188), we examined whether specific types of pictograph icons influence the processing strategy viewers use to extract numerical information. In addition, we examined the effect of iconicity and numeracy on probability estimation, recall, and icon liking. This experiment used a 2 (iconicity: blocks vs. restroom icons) × 2 (scenario: medical vs. nonmedical) between‐subject design. Numeracy had a significant effect on information processing strategy, but we found no effect of iconicity or scenario. Results indicated that both icon types enabled high and low numerates to use their default way of processing and extracting the gist of the message from the pictorial risk communication format: high numerates counted icons, whereas low numerates used large‐area processing. There was no effect of iconicity in the probability estimation. However, people who saw restroom icons had a higher probability of correctly recalling the exact risk level. Iconicity had no effect on icon liking. Although the effects are small, our findings suggest that person‐like restroom icons in pictographs seem to have some advantages for risk communication. Specifically, in nonpersonalized prevention brochures, person‐like restroom icons may maintain reader motivation for processing the risk information.     

Why do participants in voluntary organizations leave? Exploring the relationship between value congruence and length of stay

Recognizing the importance of values and the specific characteristics of participants and situations in voluntary organizations, we examine how value congruence—the fit or compatibility of values between participants and the organization, or among participants—interacts with personal and situational factors to predict participants' length of stay in their organizations. Introducing the case of a voluntary organization that offers shared housing, we measure value congruence through textual similarity in the self‐introduction documents of 49 participants and the organization's mission statement. This approach differs from the self‐reported measures based on participants' perceptions or recalled interactions used in previous studies. In line with expectation‐disconfirmation theory, participants with the strongest beliefs in organizational values had shorter lengths of stay. The amount of intraorganizational communication also moderated the relationship between value congruence and length of stay. This study provides theoretical and methodological implications for nonprofit management by considering personal and situational factors and evaluating value congruence by textual similarity.     

数控加工与编程数字化教学资源建设

为培养高职数控技术专业学生的数控加工与编程能力,通过调研典型制造型企业,以其岗位能力需求为基础,以企业的实践过程为任务流程,规划了数控加工与编程课程的教学体系,并构建了基于网络化教学平台的数字化教学资源库。     

Longitudinal relations between behavioral inhibition and social information processing: Moderating role of maternal supportive reactions to children's emotions

Utilizing multiple measures of interpretive biases, the current study examined the roles of toddlers’ behavioral inhibition (BI) and maternal supportive reactions to children's negative emotions in relation to children's interpretive biases across middle to late childhood. Toddlers’ BI was measured during several laboratory tasks (n = 248) at 2 and 3 years of age. Mothers reported on their reactions to children's negative emotional expressions when children were 7 years old (n = 203), and children's interpretations of social cues were assessed at 7 and 10 years of age (n s = 179 and 161, respectively). Toddlers with high levels of BI expressed less positivity toward social engagement with unfamiliar peers during discussion of ambiguous social situations. Further, children with high BI were less likely to attribute the cause of negative social situations to external factors, particularly when mothers were less accepting of children's negative emotional displays. Findings are discussed in terms of cognition related to the interpretation of ambiguous and threat‐related social situations among temperamentally at‐risk children.     

社会网络、 先前经验与创业风险识别

无法识别创业风险是导致创业失败的主要原因之一,如何有效识别并管理创业风险是新创企业健康成长的关键.社会网络能够弥补创业者在识别风险过程中的信息劣势,但既有研究极少探索社会网络是否以及如何影响创业风险识别.为弥补这个研究空白,文章利用信息处理理论为研究框架,构建了创业风险识别模型.具体而言,结构洞和网络强度有利于创业者获取更多、高质量与风险相关的信息,进而识别更多的创业风险;获取信息的数量在网络强度与创业风险识别关系之间发挥完全中介作用;创业者的先前经验正向影响创业风险识别,并对结构洞与获取信息的数量之间关系起调节作用.文章讨论了研究结果的理论贡献与实践启发.