Poverty and Material Hardship in Grandparent‐Headed Households

Using the 2001 Survey of Income and Program Participation, the current study examines poverty and material hardship among children living in 3‐generation (n = 486), skipped‐generation (n = 238), single‐parent (n = 2,076), and 2‐parent (n = 6,061) households. Multinomial and logistic regression models indicated that children living in grandparent‐headed households experience elevated risk of health insecurity (as measured by receipt of public insurance and uninsurance)—a disproportionate risk given rates of poverty within those households. Children living with single parents did not share this substantial risk. Risk of food and housing insecurity did not differ significantly from 2‐parent households once characteristics of the household and caregivers were taken into account.     

空气冲旋钻头牙齿失效分析与新材料实验研究

针对目前空气冲旋钻头钻进中牙齿频繁断裂、脱落以及磨损严重，导致破岩效率低、使用寿命短等问题，采用纳米改型技术，在硬质合金中掺杂纳米Al₂O₃制备出Al₂O₃/WC Co纳米/微米复合材料，对其性能、组织结构进行分析，对其耐磨性、耐冲击性进行实验研究，结果表明：加入3%的纳米Al₂O₃并添加适量的抑制剂和稀土元素能明显改善Al₂O₃/WC Co纳米/微米复合材料的组织结构、细化晶粒，复合材料的耐磨性和耐冲击性能得到大幅提高，较硬质合金YG8提高4～8倍。为大幅度提高钻头破岩效率，延长钻头使用寿命提供了可能性。     

网络故障实时监测实现技术

通过分析TCP/IP协议中的ICMP特殊报文机制 ,提出利用Delphi编程调用Windows/WindowsNT自带的Ping程序 ,巧妙而可靠的解决了网络故障的实时监测问题 ,并应用于我校校园网     

HIV/AIDS stigma in Chinese Internet forums: a content analysis approach

This study examines the stigmatization of HIV/AIDS and people living with HIV/AIDS (PLHA) on three popular Chinese Internet forums. A corpus of 275 entries discussing AIDS and PLHA was coded, based on a scheme of five stigmatizing behaviors. A high percentage of postings showed at least one and often several stigmatizing behaviors. These findings suggest that participants openly revealed their fears and biases about AIDS and PLHA online. In addition, when sexual behaviors were identified in the entries, a higher likelihood to stigmatize, a greater absence of empathy, and more intense negative emotions were shown. Further investigation of the five variables of stigmatization shows that labeling, negative attribution, and responsibility were the most frequent stigmatizing behaviors in these messages. Implications of this tendency to feel free to stigmatize HIV/AIDS and PLHA in online forums are discussed. The study also provides suggestions to health practitioners and policy makers for how to address online AIDS stigmatizing behavior.     

光伏发电在电动阀门中的应用

为了克服电动阀门在沙漠和其他地区供电难的问题,提出了用光伏电池为蓄电池充电,用蓄电池的电能为电动阀控制系统供电,并用DSP实现全数字软件锁相环(DSPLL)控制直流电机可逆调速的脉冲宽度调节(PWM)。试验证明光伏电池能满足电动阀门的开、关所需要的电能,该方法不仅能实现整个系统的功能,而且其性能稳定可靠,减少系统的谐波和纹波成分,使整个控制系统能实时地遥控、数据采集和传输、液晶显示电机转矩,使直流电机稳速高精度控制阀门的流量。     

Marriage Expectations Among African American Couples in Early Adulthood: A Dyadic Analysis

Using Family and Community Health Study data consisting of 168 unmarried, primarily African American couples, the current study sought to understand the dyadic interplay among school, work, and partner-specific marriage expectations in early adulthood. Drawing on the economic prospects, adult transitions, and work - family literatures, the authors hypothesized and found ample support that expectations to marry a romantic partner were linked not only to one's own school and work-related experiences but also to those of a partner. These associations held while controlling for relationship satisfaction, general views of marriage, and other covariates that have been posited to explain racial inequalities in relationship and marriage patterns. Furthermore, the authors found that actor covariates of marital expectations differed from partner covariates, a finding that highlights the advantages of dyadic analyses in helping researchers understand marriage as both a developmental and interpersonal process.     

IT security planning under uncertainty for high-impact events

While many IT security incidents result in relatively minor operational disruptions or minimal recovery costs, occasionally high-impact security breaches can have catastrophic effects on the firm. Unfortunately, measuring security risk and planning for countermeasures or mitigation is a difficult task. Past research has suggested risk metrics which may be beneficial in understanding and planning for security incidents, but most of these metrics are aimed at identifying expected overall loss and do not directly address the identification of, or planning for, sparse events which might result in high-impact loss. The use of an upper percentile value or some other worst-case measure has been widely discussed in the literature as a means of stochastic optimization, but has not been applied to this decision domain. A key requirement in security planning for any threat scenario, expected or otherwise, is the ability to choose countermeasures optimally with regard to tradeoffs between countermeasure cost and remaining risk. Most of the planning models in the literature are qualitative, and none that we are aware of allow for the optimal determination of these tradeoffs. Therefore, we develop a model for optimally choosing countermeasures to block or mitigate security attacks in the presence of a given threat level profile. We utilize this model to examine scenarios under both expected threat levels and worst-case levels, and develop budget-dependent risk curves. These curves demonstrate the tradeoffs which occur if decision makers divert budgets away from planning for ordinary risk in an effort to mitigate the effects of potential high-impact outcomes.     

Variance reduction for kernel estimators in clustered/longitudinal data analysis

We develop a variance reduction method for the seemingly unrelated (SUR) kernel estimator of Wang (2003). We show that the quadratic interpolation method introduced in Cheng et al. (2007) works for the SUR kernel estimator. For a given point of estimation, Cheng et al. (2007) define a variance reduced local linear estimate as a linear combination of classical estimates at three nearby points. We develop an analogous variance reduction method for SUR kernel estimators in clustered/longitudinal models and perform simulation studies which demonstrate the efficacy of our variance reduction method in finite sample settings.     

居民消费价格指数的季节调整及短期预测

文章首先论述了季节调整方法的发展过程;然后把居民消费价格指数的同比数据转换为定基比数据.运用国际上最新流行的X-12-ARIMA程序对我国居民消费价格指数时间序列进行季节调整:再运用TRAMO/SEATS方法剔除中国特有的春节假日因素;最后对CPI进行短期预测,得出了我国的通货膨胀可能还会持续一段时间的结论.