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51.
This research challenges the presumption that reading online reviews solely affect reader attitudes toward a prospective decision. Instead, readers may strategically select and read reviews after a decision. This research advances and tests hypotheses proposing that: (1) post-decision readers select decision-supportive reviews earlier and more frequently; and (2) the reviews they read affect the subsequent cognitive dissonance they experienced. Two studies employed an original post-decision experiment and demonstrated that readers expressed biased review selection. Interestingly, the reviews they read affected and increased their cognitive dissonance. The findings contributed to understanding the complex dynamic of online reviews in a post-decision context. 相似文献
52.
Scientific publications on ozone decay kinetics in water report very wide result variations, depending on a multiplicity of factors, such as ozone concentration, pH, temperature, alkalinity, fluid-dynamic conditions, presence of UV radiations, and concentration of organic and inorganic carbon. This paper intends to provide an engineering-oriented review that summarizes and compares the main results reported in the recent literature so that the condensed information can guide the reader in getting operational indications to assist applications and research. 相似文献
53.
The ocean waves are an important renewable energy resource that, if extensively exploited, may contribute significantly to the electrical energy supply of countries with coasts facing the sea. A wide variety of technologies has been proposed, studied, and in some cases tested at full size in real ocean conditions. Oscillating-water-column (OWC) devices, of fixed structure or floating, are an important class of wave energy devices. A large part of wave energy converter prototypes deployed so far into the sea are of OWC type. In an OWC, there is a fixed or floating hollow structure, open to the sea below the water surface, that traps air above the inner free-surface. Wave action alternately compresses and decompresses the trapped air which is forced to flow through a turbine coupled to a generator. The paper presents a comprehensive review of OWC technologies and air turbines. This is followed by a survey of theoretical, numerical and experimental modelling techniques of OWC converters. Reactive phase control and phase control by latching are important issues that are addressed, together with turbine rotational speed control. 相似文献
54.
Natural products have been in use long before the introduction of modern drug therapies and are still used in various communities worldwide for the treatment of anterior eye disease. The aim of this review is to look at the current non-pharmaceutical modalities that have been tried and assess the body of existing evidence behind them. This includes alternative medicine, existing non-pharmaceutical therapy and more recent low and high tech solutions.A detailed search of all available databases including MEDLINE, Pubmed and Google was made to look for English-language studies for complementary and alternative treatment modalities (CAM), natural therapies and new modalities for anterior eye disease such as blepharitis, dry eye and microbial keratitis. We have included a broad discussion ranging from traditional treatments like honey and aloe vera which have been used for centuries, to the more recent technological advances like Intense Pulsed Light (IPL), LipiFlow and photoactivated chromophore for corneal cross linking in infectious keratitis (PACK-CXL).Alternative management strategies may have a role in anterior eye diseases and have a potential in changing the way we currently approach them. Some of the available CAM could play a role if incorporated in to current management practices of not only chronic diseases like blepharitis and dry eye, but also acute conditions with significant morbidity like microbial keratitis. Further large-scale randomized control trials stratified by disease severity are required to improve our understanding and to evaluate the use of non-pharmaceutical therapy against current practice. 相似文献
55.
Understanding industries in terms of the concepts of chains, clusters and networks is becoming increasingly important in economies around the world. Supply chain management for an individual organization is an emerging field of research in the construction management discipline, but less attention has been devoted to investigating the nature of the construction supply chains and their industrial organizational economic environment. This selected review of construction and mainstream management supply chain literature is organized around four themes; distribution, production, strategic procurement management and industrial organization economics, and highlights the need to develop an industrial organization economic supply chain framework for construction. The merging of the supply chain concept with the industrial organization model as a methodology for understanding firm conduct and industry structure and performance is an important contribution to both construction supply chain and construction economic theory. Much of the industrial organization supply chain literature has tended to focus upon manufacturing industries, where typically firms are permanent organizations. This raises issues as to the differences between industries founded upon temporary compared with permanent organizations. There is potential for the development of an industrial organization methodology applicable to the project based industry. Ultimately industrial organization research seeks to have direct implications for industry performance and government policies. 相似文献
56.
57.
地下无轨矿山辅助设备(车辆)综述 总被引:2,自引:0,他引:2
论述了辅助设备通用底盘、井下装药车、撬毛台车、锚杆台车、混凝土喷射机和其他无轨辅助车辆的使用现状及其今后发展趋势。 相似文献
58.
茂锆羧酸类配合物由于具有潜在的超强酸催化性能而备受关注。本文对其合成及晶体结构等在近些年的研究进展进行了综述。 相似文献
59.
Poly (lactic acid) or polylactide (PLA) is an aliphatic thermoplastic polyester produced from renewable resources and is compostable in the environment. Because of the massive use of foamed products of petroleum-based polymers, PLA foams have been considered as substitutes for some of these products. Specifically, because of PLA's competitive material and processing costs, and its comparable mechanical properties, PLA foams could potentially replace polystyrene (PS) foam products in a wide array of applications such as packaging, cushioning, construction, thermal and sound insulation, and plastic utensils. Due to their biocompatibility, PLA foams can also be used in such biomedical applications as scaffolding and tissue engineering. But PLA has several inherent drawbacks, which inhibit the production of low-density foams with uniform cell morphology. These drawbacks are mainly the PLA's low melt strength and its slow crystallization kinetics. During the last two decades, researchers have investigated the fundamentals of PLA/gas mixtures, PLA foaming mechanisms, and the effects of material modification on PLA's foaming behavior through various manufacturing technologies. This article reviews these investigations and compares the developments made thus far in PLA foaming. 相似文献
60.
发动机气门成形加工发展综述 总被引:1,自引:0,他引:1
叙述了发动机气门成形加工的生产现状和发展趋势:气门材料的高合金化加大了成形加工的难度;挤压成形、剪裁拼接毛坯等新技术正在气门成形中得到日益广泛的应用,焊接和热处理新技术对提高气门质量和使用寿命起着重要的作用;信息化管理,成形过程自动化、智能化,新工艺的开发应用将是气门成形加工的进一步发展方向. 相似文献