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141.
"90后"一代正处于15-24岁的青少年时期,是社会主义核心价值观培育与践行的重要人群。对上海、武汉和天津三地"90后"青少年的诚信观与友善观进行问卷调查结果表明,青少年对"友善"的认同显著高于对"诚信"的认同;随年级升高,诚信观趋向消极;女生对"诚信"和"友善"的认同均高于男生。家庭物质经济条件、生活安全感、亲子关系、同学关系、上网时间及青少年自我评价等对于社会主义核心价值观的认同影响显著。  相似文献   
142.
Several colorectal cancer (CRC) screening models have been developed describing the progression of adenomas to CRC. Currently, there is increasing evidence that serrated lesions can also develop into CRC. It is not clear whether screening tests have the same test characteristics for serrated lesions as for adenomas, but lower sensitivities have been suggested. Models that ignore this type of colorectal lesions may provide overly optimistic predictions of the screen‐induced reduction in CRC incidence. To address this issue, we have developed the Adenoma and Serrated pathway to Colorectal CAncer (ASCCA) model that includes the adenoma‐carcinoma pathway and the serrated pathway to CRC as well as characteristics of colorectal lesions. The model structure and the calibration procedure are described in detail. Calibration resulted in 19 parameter sets for the adenoma‐carcinoma pathway and 13 for the serrated pathway that match the age‐ and sex‐specific adenoma and serrated lesion prevalence in the COlonoscopy versus COlonography Screening (COCOS) trial, Dutch CRC incidence and mortality rates, and a number of other intermediate outcomes concerning characteristics of colorectal lesions. As an example, we simulated outcomes for a biennial fecal immunochemical test screening program and a hypothetical one‐time colonoscopy screening program. Inclusion of the serrated pathway influenced the predicted effectiveness of screening when serrated lesions are associated with lower screening test sensitivity or when they are not removed. To our knowledge, this is the first model that explicitly includes the serrated pathway and characteristics of colorectal lesions. It is suitable for the evaluation of the (cost)effectiveness of potential screening strategies for CRC.  相似文献   
143.
We study multiple-class classification problems. Both ordinal and categorical labeled cases are discussed. The common approaches for multiple-class classification are built on binary classifiers, in which one-versus-one and one-versus-rest are typical approaches. When the number of classes is large, then these binary-classifier-based methods may suffer from either computational costs or the highly imbalanced sample sizes in their training stage. In order to alleviate the computational burden and the imbalanced training data issue in multiple-class classification problems, we propose a method that has competitive performance and retains the ease of model interpretation, which is essential for a prognostic/predictive model.  相似文献   
144.
高旭 《今日辽宁》2014,(5):62-63
一项项民间技艺如一颗颗美丽的珍珠,散落在乡野间的每个角落,经过岁月的打磨,散发出温润的光泽.而作为非遗工作者,就是那些采撷珠宝的人,要将它们一一串联,使其绽放更为动人的夺目光彩.2013年的初夏,我和同事们来到朝阳,找寻那颗遗留在深山里的珍珠——朝阳民间刺绣.  相似文献   
145.
This study develops a robust automatic algorithm for clustering probability density functions based on the previous research. Unlike other existing methods that often pre-determine the number of clusters, this method can self-organize data groups based on the original data structure. The proposed clustering method is also robust in regards to noise. Three examples of synthetic data and a real-world COREL dataset are utilized to illustrate the accurateness and effectiveness of the proposed approach.  相似文献   
146.
吴璟  徐曼迪 《统计研究》2021,38(9):75-88
本文围绕城镇家庭户自然增长、城镇家庭户机械增长和城镇存量住房拆除三项需求来源,设计了基于人口普查等公开统计数据定量测算城镇新增住房需求规模的系统性方法,对2001—2010年和2011—2015年间全国和各省份城镇新增住房需求规模进行测算与分析。在此期间新增住房供需关系经历了从基本均衡向供过于求的变化,同时存量住房拆除引致的被动需求取代城镇家庭户自然增长和机械增长引致的主动需求,成为新增住房需求的最主要来源。东、中、西部省份在新增需求规模、新增供需比、需求结构等方面表现出明显差异。本文还进一步对2021—2030年的发展趋 势进行了定量预测。由于三项需求来源均趋于下降,2021—2025年和2026—2030年间全国年均城镇新增住房需求规模预计将较2011—2015年间分别下降33%和53%。本文设计的城镇新增住房需求规模测算方法和预测思路能够为各级政府“十四五”住房发展规划编制、房地产企业战略制定等提供参考。  相似文献   
147.
This study employs a qualitative multiple-case study to explore relational management mechanisms for strategic nonprofit alliances (NPAs) formed by at least 3 nonprofit organizations by examining collaborative relationships among farmers associations in Taiwan. We explore these mechanisms by analyzing case data from four strategic cooperation characteristics, which can best explain NPAs. To effectively sustain partnerships, our findings suggest that an NPA applies acceptable collaborative rules and regulations, common standard procedures, symmetric information and communication, and capability building and corrective measures when cooperation involves high input commonality. The results also suggest empowerment for partners with deeper input commitment to direct decisions on resource distribution and utilization when collaborative ties involve low input measurability. Regarding high output commonality, we advise NPAs to enforce common output quality control, efficient substandard-output treatment, and external incentives as mechanisms to encourage partners for continued commitment. If relationships involve low output measurability, our findings suggest that NPAs heighten partners’ voluntary motivation for the common good, with goal-achievement assessment measures, professional certification by external experts, and acceptable and reasonable benefit-sharing methods  相似文献   
148.
信息化建设是医联体建设的重要内容和重点领域。现阶段的医联体信息化建设存在着医疗信息数据难共享、医疗隐私数据易泄露、医疗数据质量难改观等问题。文章通过梳理区块链的技术原理,发现区块链技术同医联体信息化建设有着高度的契合性并能以智能化的应对方式密切医患互动关系、保障数据高效共享、加强数据安全治理以及提升数据准确性、一致性、时效性和规整性,因此,区块链技术嵌入医联体信息化建设具有可行性。但区块链技术应用于医联体信息化建设在技术、理念、监管等方面还存在诸多挑战,未来仍需提升技术应用手段、转变医方观念体系、健全法规监管模式。  相似文献   
149.
The goal of this study was to examine child and parent predictors of children's hostile attribution bias (HAB) with a particular focus on exploring the associations between parents’ early attribution of child misbehavior and children's HAB in the transition to school age. Participants were 241 children (118 girls) of middle‐income families who were at risk for school‐age conduct problems. Multi‐method, multi‐informant data were collected on maternal attributions of child misbehavior, parental use of corporal punishment, and child attributes (i.e., verbal IQ, effortful control, theory of mind, and emotional understanding) at 3 years, and child HAB in ambiguous situations at 6 years. Results indicated that mothers’ internal explanations for children's misconduct may either reduce or increase children's later HAB depending on the specific content of attributions, such that mothers’ belief that children misbehave because of their internal state (i.e., emotional state or temperament) was associated with lower levels of child HAB, whereas attributing power‐based motives (i.e., manipulative, controlling intentions) in children was associated with higher levels of HAB. The findings are discussed with respect to appreciating the complexity of parents’ explanations for children's behavior, and considering parental cognition as a potential target for early identification and prevention of child HAB and related problems.  相似文献   
150.
This study investigates causal structure among daily Chicago Board of Trade corn futures prices and seven regional cash series from Iowa, Illinois, Indiana, Ohio, Minnesota, Nebraska, and Kansas for January 2006–March 2011. Their wavelet transformed series are further analyzed for causal relationships at different time scales. Empirical results indicate no causality among states or between the futures and a cash series for time scales shorter than one month. As scales increase but do not exceed a year, bidirectional causal flows are determined among all prices. The information leadership role of the futures against a cash price is identified for the scale longer than one year and raw series, at which no interstate causality is found.  相似文献   
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