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91.
The research analyses decisions as evaluative outcomes regarding project value. The UK-French Hinkley Point C Nuclear Power Station provides the case study. Value is traditionally assessed as inputs and outputs. Here, value is conceptualized as a co-created value proposition at the front-end with implications for realization post-completion. Service-dominant logic (SDL) provides the theoretical lens and contributes to a methodological approach for examining projects. Decision-making outcomes provide the evidence from a range of data sources, including reports and commentaries. The methods are interpretative. The findings show that decision-making extends beyond the time-cost-quality/scope dimensions. The long-term issues regarding value realized are often overlooked. Stakeholders and individual actors have mainly focused upon managing political and financial risks, especially time and cost. The research poses challenges to project management analysis, SDL and research design in assessing evidence. Addressing these issues facilitates a knowledge contribution to SDL theorization and the field of project management.  相似文献   
92.
Sebastian Biba 《国际水》2018,43(5):622-641
This article analyzes China’s Mekong River politics before and after the establishment of the Lancang-Mekong Cooperation (LMC) from a comparative benefit-sharing perspective. China’s pre-LMC approach focused too much on the creation of economic benefits from and beyond the river while neglecting ecological benefits to the river. Moreover, despite the problems this ‘old’ approach caused for China and its downstream neighbours, China’s current LMC strategy seems to essentially replicate its former approach. While sustainable water resources management is identified as a priority area, actual cooperation and benefit sharing in this field remain insufficient.  相似文献   
93.
We define the emerging research field of applied data science as the knowledge discovery process in which analytic systems are designed and evaluated to improve the daily practices of domain experts. We investigate adaptive analytic systems as a novel research perspective of the three intertwining aspects within the knowledge discovery process in healthcare: domain and data understanding for physician- and patient-centric healthcare, data preprocessing and modelling using natural language processing and (big) data analytic techniques, and model evaluation and knowledge deployment through information infrastructures. We align these knowledge discovery aspects with the design science research steps of problem investigation, treatment design, and treatment validation, respectively. We note that the adaptive component in healthcare system prototypes may translate to data-driven personalisation aspects including personalised medicine. We explore how applied data science for patient-centric healthcare can thus empower physicians and patients to more effectively and efficiently improve healthcare. We propose meta-algorithmic modelling as a solution-oriented design science research framework in alignment with the knowledge discovery process to address the three key dilemmas in the emerging “post-algorithmic era” of data science: depth versus breadth, selection versus configuration, and accuracy versus transparency.  相似文献   
94.
The article analyses and compares some free-to-use patent search services which are not managed by patent authorities but which may offer unique selling propositions (USPs) beyond the expected, standard, search functions. Those services selected for this study are Google Patents, Lens, Patent Inspiration, Free Patents Online, SureChEMBL and Octimine. For this comparative study a total set of 66 criteria were analysed for each of the six search services. Furthermore the USPs and perceived advantages and disadvantages were identified. The study concluded that some of these search services are better suited for general prior art searches or patent analysis while others are applicable for patent searches in specific fields like biotechnology or pharmaceuticals.  相似文献   
95.
96.
ABSTRACT

The main contribution of this paper is a new definition of expected value of belief functions in the Dempster–Shafer (D–S) theory of evidence. Our definition shares many of the properties of the expectation operator in probability theory. Also, for Bayesian belief functions, our definition provides the same expected value as the probabilistic expectation operator. A traditional method of computing expected of real-valued functions is to first transform a D–S belief function to a corresponding probability mass function, and then use the expectation operator for probability mass functions. Transforming a belief function to a probability function involves loss of information. Our expectation operator works directly with D–S belief functions. Another definition is using Choquet integration, which assumes belief functions are credal sets, i.e. convex sets of probability mass functions. Credal sets semantics are incompatible with Dempster's combination rule, the center-piece of the D–S theory. In general, our definition provides different expected values than, e.g. if we use probabilistic expectation using the pignistic transform or the plausibility transform of a belief function. Using our definition of expectation, we provide new definitions of variance, covariance, correlation, and other higher moments and describe their properties.  相似文献   
97.
采动覆岩卸荷膨胀累积效应   总被引:2,自引:0,他引:2  
地下煤层开采引起的岩层运动是一系列安全和环境问题的根源,研究采动岩层运动规律是安全、高效、绿色开采的重要基础。通过对岩层运动过程的研究,揭示了采动覆岩卸荷膨胀累积效应及其对岩层运动规律的影响机制。研究表明:采动覆岩经历了卸荷膨胀与再压实的动态过程。受关键层结构控制,上覆岩层由下向上成组破断运动,关键层破断前,阻断了上覆载荷向下方岩层的传递,导致其因卸荷而产生膨胀,包括碎胀与弹性膨胀。随着关键层破断高度增加,覆岩卸荷高度同步增大,因卸荷而膨胀的岩层总厚度不断增大;同时卸荷煤岩也受到已破断关键层载荷的压实作用,从而造成覆岩卸荷膨胀总量的不断变化。将这种覆岩卸荷膨胀总量随覆岩卸荷高度动态变化的现象定义为采动覆岩卸荷膨胀累积效应,进而建立了理论模型,并通过淮北海孜煤矿巨厚火成岩下采煤覆岩裂隙实测进行了验证。结果表明,采动覆岩卸荷膨胀累积效应对采动岩层运动规律产生了重要影响,如影响覆岩关键层下离层量,影响覆岩关键层贯通破断的高度,影响不同开采条件的地表下沉系数等。采动覆岩卸荷膨胀累积效应改变了对离层存在形式的传统认识,该效应的存在导致关键层下最大离层量一般小于采高的10%,覆岩可注浆充填空间并非传统认识上的“离层区”,而主要是注浆充填压力“压实”作用下将覆岩卸荷累积膨胀所转化出的那部分空间,该发现指导了覆岩隔离注浆充填绿色开采技术的创新研发及其在建筑物压煤开采中的成功实践。  相似文献   
98.
Telomere length (TL) influences the development of lifestyle-related diseases, and neonatal TL may influence their prevalence. Various factors have been reported to affect neonatal TL. Although the fetus is exposed to multiple conditions in utero, the main factors affecting the shortening of neonatal TL are still not known. In this study, we sought to identify factors that influence fetal TL. A total of 578 mother-newborn pairs were included for TL analysis. TL was measured in genomic DNA extracted from cord blood samples using quantitative PCR. The clinical factors examined at enrollment included the following intrauterine environmental factors: maternal age, assisted reproductive technology (ART) used, body mass index (BMI), gestational diabetes mellitus (GDM), maternal stress, smoking, alcohol consumption, preterm delivery, small-for-gestational-age, neonatal sex, and placental weight. Univariate and multivariate regression analyses were used to verify the relationship between neonatal TL and these clinical factors. The median neonatal TL to single-copy gene ratio was 1.0. Pregnancy with ART was among the 11 factors associated with shorter neonatal TL. From multiple regression analysis, we determined that neonatal TL was significantly shorter for pregnancies in the ART group than in the other groups. We conclude that pregnancy with ART is associated with shorter neonatal TL.  相似文献   
99.
黄伟 《金属热处理》2020,45(5):266-271
针对氧化铝行业中常用的Cr28和Cr20高铬铸铁伞帽在相同工况条件下的磨损机理进行分析,并对比研究了实际生产中两种失效材料的成分、组织及性能。结果表明,伞帽部件在高温强碱腐蚀条件下受到外界冲刷时,磨损量由微切削磨损与变形磨损这两种机制共同决定。含铬量较高的Cr28高铬铸铁,其冲刷和抗腐蚀磨损性能均优于Cr20高铬铸铁。伞帽服役寿命主要受浆料和表层的铸铁材料两大因素影响。两种试验材料经淬火+回火处理后,基体组织中主要为回火马氏体+M7C3型碳化物+少量残留奥氏体,其中含铬量较高的Cr28高铬铸铁中共晶碳化物含量更高,且分布更加弥散,其平均硬度值为64.0 HRC,高于Cr20高铬铸铁的60.2 HRC。最终确定Cr28高铬铸铁作为伞帽材质更能满足氧化铝生产及设备检修周期的需要。  相似文献   
100.
张庄铁矿设计采矿方法为大直径深孔阶段空场嗣后充填法。为了最大化发挥采矿设备性能,降低采切工程量,提高回采效率,通过实施一系列技术攻关,实现了将采矿阶段高度由原来的60 m提高到90 m。而作为最初爆破回采的自由面及爆破补偿空间,切割天井施工工艺为影响高阶段矿房爆破回采效果的关键因素,施工质量的优劣,直接影响矿房爆破回采生产作业能否顺利进行,而二次处理在增加施工成本的同时将带来安全隐患。张庄铁矿在面临可参考的成熟经验较少的情况下,结合现场可用的作业条件采取了对比试验的方法,在安全、技术及经济多方面综合分析比较下,确定了最终方案,为张庄铁矿安全稳定生产奠定了基础,同时研究成果可为大型地下矿山生产实践提供一定的参考。  相似文献   
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