Verification in biometric systems: problems and modern methods of their solution

The paper deals with the problem of electronic verification of people on the basis of measurement information of a fingerprint reader and new approaches to its solution. The offered method guaranties the restriction of error probabilities of both type at the desired level at making a decision about permitting or rejecting the request on service in the system. On the basis of investigation of real data obtained in the real biometrical system, the choice of distribution laws is substantiated and the proper estimations of their parameters are obtained. Using chosen distribution laws, the normal distribution for measurement results of characteristics of the people having access to the system and the beta distribution for the people having no such access, the optimal rule based on the Constrained Bayesian Method (CBM) of making a decision about giving a permission of access to the users of the system is justified. The CBM, the Neyman–Pearson and classical Bayes methods are investigated and their good and negative points are examined. Computation results obtained by direct computation, by simulation and using real data completely confirm the suppositions made and the high quality of verification results obtained on their basis.     

Too old to test? Prevalence and correlates of HIV testing among sexually active older adults

ABSTRACT

Older adults account for 17% of new HIV diagnoses in the US and are more likely to be diagnosed with HIV later in the course of the disease compared to younger people. We calculated the prevalence and associated factors of having ever been tested for HIV among sexually active older adults. We analyzed data from the 2008–2016 General Social Survey Limited to respondents ≥65 years of age who reported more than one sex partner(s) in past 12 months (n = 757). HIV testing prevalence, prevalence ratios, and 95% confidence intervals were calculated by demographic variables and HIV-related risk behaviors. An estimated 16.3% of sexually active older adults have tested for HIV, and 15.9% were at increased risk for HIV infection (reported injection drug and/or crack–cocaine use, exchanging money for sex, more than three sex partners in the past year, or men who reported having sex with another man). In the adjusted model, adults aged 65–70, not married, self-identified as gay/bisexual, and at increased risk for HIV infection were more likely to have tested for HIV. An estimated 83.7% of sexually active older adults never tested for HIV. Strategies are needed to increase HIV awareness and testing among potentially high-risk older adults.     

允许直达的混合轴辐式快递网络规划模型与算法研究

在快递企业的日常运营中,当两个城市之间的快递业务量达到一定规模之后会允许该城市对之间开展直达递送。但是这一规则通常仅在快递网络规划完成之后由相关子公司提请实施。为弥补这一实际规则的局部最优性缺陷,本论文将直达问题纳入网络规划决策,基于全局优化的视角构建了允许直达的混合轴幅式快递网络规划决策模型,设计了相应的求解流程,并对其中的指派关系决策构建了遗传算法。基于国内标杆企业的数值案例计算证明了该决策模型与求解方法的有效性,研究结果还说明,相对于纯轴辐式结构,允许直达的混合轴幅式网络结构有助于降低网络总成本,同时在直达线路上能够有效的降低迂回、提高服务时效性和服务水平。     

基于改进遗传算法的置换装配线调度问题研究

企业的置换装配线调度问题（Permutation Assembly-line Scheduling Problem,PASP）是一类典型的NP-hard型生产调度问题,是现代集成制造系统CIMS极为关心的问题。该问题可以具体描述为n个工件要在m台机器上加工,每个工件需要经过m道工序,每道工序要求不同的机器,这n个工件通过m台机器的顺序相同,它们在每台机器上的加工顺序也相同,问题的主要目标是找到n个工件在每台机器上的最优加工顺序,使得最大完工时间最小。由于PASP问题的NP-hard性质,本文使用遗传算法对其进行求解。尽管遗传算法常用以求解调度问题,但其选择与交叉机制易导致局部最优及收敛慢。因此,本文提出基于区块挖掘与重组的改进遗传算法用于求解置换装配线调度问题。首先通过关联规则挖掘出不同的优秀基因,然后将具有较优结果的基因组合为优势区块,产生具优势的人工解,并引入高收敛性的局部搜索方法,提高搜索到最优解的机会与收敛效率。本文以OR-Library中Taillard标准测试例来验证改进遗传算法的求解质量与效率,结果证明：本文所提算法与其它求解调度问题的现有5种知名算法相比,不仅收敛速度较快,同时求解质量优于它们。     

体外胚胎的基因遗传权保护问题探析————兼评“江苏无锡冷冻胚胎案”

体外胚胎作为现代医疗科学技术发展的产物,在改变人类生殖体系的同时,引发了一系列亟待解决的相关法律问题。通过对目前国内相关学者所提出的“主体说”“客体说”和“中介说”等学说的批判性思考,揭示其在理论层面的局限性,从而得以否定以上三种学说的合理性。而后从伦理学、法理以及比较法等角度对该问题进行系统性的论述,揭示体外胚胎的法律地位,即人格利益属性。在该定性的基础之上,借助于有关学者提出的基因权理论,最终将体外胚胎界定为基因遗传权的客体。因此,有必要对江苏无锡冷冻胚胎案的裁判结果予以重新审视。同时,建议在立法层面建立起体外胚胎基因遗传权的法律保护体系,完善侵害基因遗传权的救济措施,以实现对体外胚胎基因遗传权的法律保护。     

Estimation of Stratified Mark‐Specific Proportional Hazards Models with Missing Marks

Abstract. An objective of randomized placebo‐controlled preventive HIV vaccine efficacy trials is to assess the relationship between the vaccine effect to prevent infection and the genetic distance of the exposing HIV to the HIV strain represented in the vaccine construct. Motivated by this objective, recently a mark‐specific proportional hazards (PH) model with a continuum of competing risks has been studied, where the genetic distance of the transmitting strain is the continuous ‘mark’ defined and observable only in failures. A high percentage of genetic marks of interest may be missing for a variety of reasons, predominantly because rapid evolution of HIV sequences after transmission before a blood sample is drawn from which HIV sequences are measured. This research investigates the stratified mark‐specific PH model with missing marks where the baseline functions may vary with strata. We develop two consistent estimation approaches, the first based on the inverse probability weighted complete‐case (IPW) technique, and the second based on augmenting the IPW estimator by incorporating auxiliary information predictive of the mark. We investigate the asymptotic properties and finite‐sample performance of the two estimators, and show that the augmented IPW estimator, which satisfies a double robustness property, is more efficient.     

Estimating the Conditional Error Distribution in Non‐parametric Regression

Abstract. We consider a general non‐parametric regression model, where the distribution of the error, given the covariate, is modelled by a conditional distribution function. For the estimation, a kernel approach as well as the (kernel based) empirical likelihood method are discussed. The latter method allows for incorporation of additional information on the error distribution into the estimation. We show weak convergence of the corresponding empirical processes to Gaussian processes and compare both approaches in asymptotic theory and by means of a simulation study.     

存在自相关时检验和估计方法的改进——基于自回归分布滞后模型的自相关检验和参数估计

存在自相关时的自相关检验和参数估计是基础计量经济学的一个重要内容,并且存在自相关时的原模型已转化为自回归分布滞后模型。讨论存在自相关时的自相关检验和参数估计问题,提出了一种基于自回归分布滞后模型的自相关检验法,并同时给出了相应的参数估计。     

中国区域环境库兹涅茨曲线的稳定性检验——基于省际面板数据

在运用F和Hausman统计检验识别环境库兹涅茨面板模型形式的基础上,选择合理的面板模型估计、检验中国30个省份环境库兹涅茨曲线的稳定性.研究结果表明:环境库兹涅茨曲线的稳定性与经济发展水平较高的地区相关性较强,与经济发展水平较低的地区相关性较弱.工业粉尘、烟尘、二氧化硫排放量估计的环境库兹涅茨曲线稳定性相对较好,工业废水、固体废物排放量估计的环境库兹涅茨曲线稳定性相对较差.在环境保护政策的约束下,除北京、上海以外,其他地区环境库兹涅茨曲线的拐点时间具有刚性特征.     

通货膨胀下的联合库存选址模型研究

研究了通货膨胀对涉及一个供应商、多个候选配送中心和零售商的三级分销网络设计的影响.不同于传统的联合库存选址模型,所研究的模型考虑了整个系统的相关成本的时间价值,其目标是使在一定的通货膨胀率下总的选址、运输和库存成本之和的现值最小.为此,建立了一个非线性的整数规划模型,该模型为无容量约束问题的扩展模型,属于NP-hard问题.提出了3种基于不同编码形式的遗传算法用于求解该模型,并通过不同规模的算例对3种算法进行了有效性的分析和对比.最后,通过对各算例的计算结果的分析,发现随着通货膨胀率的增长,为了使这个分析网络的总成本现值最小,需要增加建立的DC的数量.