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关键词： 分离式立交桥   拼宽设计   设计实例  

摘要： 以多例已经实施的工程设计为例,介绍改扩建工程中分离式立交桥的各种拼宽设计方法,提出设计过程中遇到的问题和解决方法。

关键词： AOA network   Crashing   Multi-objective problem   NSGA-II   Time value of money   Time–cost tradeoff  

摘要： The time-cost tradeoff problem is one of the most important and applicable problems in project scheduling area. There are many factors that force the mangers to crash the time. This factor could be early utilization, early commissioning and operation, improving the project cash flow, avoiding unfavorable weather conditions, compensating the delays, and so on. Since there is a need to allocate extra resources to short the finishing time of project and the project managers are intended to spend the lowest possible amount of money and achieve the maximum crashing time, as a result, both direct and indirect costs will be influenced in the project, and here, we are facing into the time value of money. It means that when we crash the starting activities in a project, the extra investment will be tied in until the end date of the project;however, when we crash the final activities, the extra investment will be tied in for a much shorter period. This study is presenting a two-objective mathematical model for balancing compressing the project time with activities delay to prepare a suitable tool for decision makers caught in available facilities and due to the time of projects. Also drawing the scheduling problem to real world conditions by considering nonlinear objective function and the time value of money are considered. The presented problem was solved using NSGA-II, and the effect of time compressing reports on the non-dominant set. © The Author(s) 2016.

关键词： CHRONIC kidney failure   HEMODIALYSIS   LONGITUDINAL method   PALLIATIVE treatment   T-test (Statistics)   ADVANCE directives (Medical care)   DATA analysis   DESCRIPTIVE statistics   PATIENT decision making  

摘要： Background: End-stage renal disease is a life-limiting illness associated with significant morbidity. Half of all individuals with end-stage renal disease are unable to participate in decision making at the end of life, which makes advance care planning critical in this population. Objective: We sought to determine the feasibility of embedding palliative medicine consultations in the hemodialysis unit during treatment runs and the impact of this intervention on advance care planning and symptom management. Design: Single-center, prospective cohort study. Setting/Subjects: Adults receiving in-center hemodialysis at a single outpatient unit were eligible. All consultations occurred during the patients' hemodialysis runs between January 1 and June 30, 2012. Measurement: Medical records were reviewed for documentation of advance directives, resuscitation status, and goals of care discussions before and after palliative medicine intervention. Symptom surveys with the Modified Edmonton Symptom Assessment Scale (validated for end-stage renal disease) were performed pre-intervention and postintervention. Results: Ninety-two patients were eligible;91 underwent palliative medicine consultation. Symptoms were well controlled at baseline prior to any intervention. After palliative medicine consultation, the prevalence of unknown code status decreased from 23% to 1% and goals of care documentation improved from 3% to 59%. Conclusion: Palliative medicine consultation during in-center outpatient hemodialysis was well received by patients and clinical staff. Patients' symptoms were well managed at baseline by the primary nephrology team. The frequency of goals of care documentation and clarification of code status improved significantly. Embedded palliative medicine specialists on the dialysis care team may be effective in improving multidisciplinary patient-centered care for patients with end-stage renal disease.

关键词： THIOLS   CLICK chemistry   NANOFABRICATION   CHEMICAL structure   CYCLODEXTRINS   SEPARATION (Technology)  

摘要： The preparation of two novel multifunctional cyclodextrin (CD) separation materials and their ultimate enantioseparation performances in high performance liquid chromatography are reported. A mild thiol-ene click reaction was used to anchor 1-allylimidazolium-per(p-methyl)-phenylcarbamoylated-beta-CD and 1-allylimidazolium-per(pchloride)phenylcarbamoylated-beta-CD onto thiol-modified porous silica giving structurally well-defined stable cationic multifunctional CD chiral stationary phases (CSP1 and CSP2 respectively). These covalently bonded CD phases have typical interaction modes such as H-bonding, pi-pi effect, electrostatic and dipole dipole interactions as well as steric effects which result in superior chiral resolution for a variety of chiral compounds in different separation modes. In a reverse-phase mode, both CSPs exhibited excellent separation abilities for isoxazolines, flavonoids, beta-blockers, and some other neutral and basic racemates. In a polar-organic mode, isoxazolines and flavonoids were well resolved. CSP1 with an electron-rich phenyl substitution on the CD rims gave a better resolution for isoxazolines whereas CSP2 with an electron-deficient phenyl substitution on the CD rims gave better resolution for flavonoids. Among isoxazolines, 4ClPh-OPr gained a high selectivity and resolution up to 18.6 and 38.7, respectively, which is an amazing result for CD enantioseparation materials.

关键词： 单通道盲源分离   挖掘机   振源贡献量分析   传递特性分析  

摘要： 研究一种新的单通道盲源分离方法,解决了传统盲源分离方法因传感器数量不足而无法有效分离源信号的问题,同时源信号幅值也得到了准确的恢复。首先利用集合经验模态分解方法将一维测量信号分解为具有不同尺度特征的本征模态函数,而后与原测量信号组成多个二维矩阵,通过稀疏分量算法得到各源信号的真实估计。利用仿真信号,与已有方法进行对比,验证了提出方法的有效性。将提出的方法应用在挖掘机动力源附近的振动分析中,成功分离出了多个振源信号。利用时频分析对源信号分别进行特征识别,并将分离结果用于振源的贡献度与声信号传递特性分析。得到各振源对于测试位置的贡献度排序,以及对于挖掘机噪声信号的传递规律,为挖掘机的减振降噪措施提供了可靠的依据。

关键词： Multiple-resources leveling   Scheduling   Symbiotic organisms search   Optimization   Construction management  

摘要： Resource leveling is used in project scheduling to reduce fluctuation in resource usage over the period of project implementation. Fluctuating resource usage frequently creates the untenable requirement of regularly hiring and firing temporary staff to meet short-term project needs. Construction project decision makers currently rely on experience-based methods to manage fluctuations. However, these methods lack consistency and may result in unnecessary waste of resources or costly schedule overruns. This research introduces a novel discrete symbiotic organisms search for optimizing multiple resources leveling in the multiple projects scheduling problem (DSOS-MRLMP). The optimization model proposed is based on a recently developed metaheuristic algorithm called symbiotic organisms search (SOS). SOS mimics the symbiotic relationship strategies that organisms use to survive in the ecosystem. Experimental results and statistical tests indicate that the proposed model obtains optimal results more reliably and efficiently than do the other optimization algorithms considered. The proposed optimization model is a promising alternative approach to assisting project managers in handling MRLMP effectively. (C) 2015 American Society of Civil Engineers.

关键词： Urban renewal   De facto segregation   Public-private sector cooperation   Public spaces   Cities & towns -- Brazil  

摘要： This article discusses the relationship between segregation and urban redevelopment projects through an analysis of Sao Paulo's metropolis. Our assumption is that segregation is one of the components of capitalist urban space, since it is produced as a commodity, which determines its fragmentation and hierarchy. In the peripheral countries, this condition prevents thousands of people to live with dignity. In recent decades, the space production has become a possibility of investment for the capital in crisis. This situation reveals the importance of the urban renewal projects, because they reinforce public and private investments in specific areas of the cities, increasing its valuation. In this article, the analysis of Nova Luz Project shows that the segregation is a content of contemporary urbanism and that the city's production process is increasingly tied to the private interests and to the capital. (C) 2015 Elsevier Ltd. All rights reserved.