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81.
This article examines the impact the UK regulatory model has had in developing and transition countries in the three decades since its inception. It presents data linked to three key features of the model, namely independent regulatory institutions; focus on competition; and greater efficiency in service delivery through incentive-based regulation. The difficulty of formulating statements valid for a very diverse set of countries is acknowledged. Nevertheless, the article argues that despite of the rapid spread of regulatory agencies across the world, the UK regulatory model has been only partially successful in middle- and low-income countries. The main explanation offered is that the ‘de-politization’ of regulatory institutions is more challenging to achieve in a context of below cost-recovery tariffs and continued state-ownership of utilities. But improving the technical soundness of decision making and introducing accountability for operators are key tasks that regulators can address even if the gap to the UK ideal remains in a number of countries. 相似文献
82.
《Measurement》2014
Display pixels of liquid-crystal-display televisions (LCD TVs) on thin-film-transistor (TFT) array are getting smaller. This paper introduced the method of voltage imaging technique, which developed and provides initial insight into the thin-film-transistor array flaw detection and measurement for ultra-high-definition (Ultra HD, UHD) LCD TV application. We proposed the measurement of flaw detection, based on TFT array testing and characterization with respect to opto-electric transformation measurement. 相似文献
83.
Little work has been reported in the literature to support k-nearest neighbor (k-NN) searches/queries in hybrid data spaces (HDS). An HDS is composed of a combination of continuous and non-ordered discrete dimensions. This combination presents new challenges in data organization and search ordering. In this paper, we present an algorithm for k-NN searches using a multidimensional index structure in hybrid data spaces. We examine the concept of search stages and use the properties of an HDS to derive a new search heuristic that greatly reduces the number of disk accesses in the initial stage of searching. Further, we present a performance model for our algorithm that estimates the cost of performing such searches. Our experimental results demonstrate the effectiveness of our algorithm and the accuracy of our performance estimation model. 相似文献
84.
近几年来,172t矿用汽车使用的K2000E发动机开始进入修理周期。白云鄂博铁矿汽修车间针对K2000E发动机与传统发动机检修方法不同,通过改进测功机与检修工具,以及管理制度改革等一系列方法,圆满的完成了对K2000E发动机的检修任务。 相似文献
85.
《低温学》2018
High-frequency pulse tube cryocooler (HPTC) has advantages of compact structure, low vibration, high reliability and long operation time. In this study, Theoretical analysis and experimental tests have been conducted in four aspects based on a developed 4 K HPTC. Firstly, a compressor with larger power output capability was employed and the impedance match between the cold head and the compressor was discussed. Secondly, simply using inertance tube configuration to replace the traditional inertance tube-gas reservoir structure. Then, the type and the size of the regenerator materials working at 4–20 K have been experimentally optimized. Finally, the performance of double-inlet working at as low as 20 K has also been tested for the first time for the HPTC. The present prototype achieved a no-load temperature of 3.6 K, which is the lowest temperature record ever reported for HPTC using helium-4 as working gas. A cooling power of 6 mW/4.2 K was also obtained with 250 W input power and a precooling power of 12.1 W/77 K. 相似文献
86.
Mette B. Petersen Jeanette Pedersen Dinah L. Holm Matthew Denwood Liza R. Nielsen 《Journal of dairy science》2018,101(8):7383-7396
Mycoplasma bovis is an important pathogen causing disease and substantial economic losses in cattle. However, knowledge of the dynamics of antibody responses in individual cows in the face of an outbreak is currently extremely limited. The use of commercial antibody tests to support clinical decision-making and for surveillance purposes is therefore challenging. Our objective was to describe the dynamics of M. bovis antibody responses in 4 Danish dairy herds experiencing an acute outbreak of M. bovis-associated disease, and to compare the antibody dynamics between dairy cows with different disease manifestations. A total of 120 cows were examined using a standardized clinical protocol and categorized into 4 disease groups: “mastitis,” “systemic,” “nonspecific,” and “none.” Paired blood and milk samples were collected and tested using a commercial M. bovis antibody–detecting ELISA. Plots of raw data and generalized additive mixed models with cow and herd as random effects were used to describe serum and milk antibody dynamics relative to the estimated time of onset of clinical disease. Cows with mastitis had high optical density measurement (ODC%) of antibodies in both milk and serum at disease onset. The estimated mean ODC% in milk was below the manufacturer's cut-off for the other groups for the entire study period. The estimated mean serum ODC% in the “systemic” group was high at onset of disease and stayed above the cut-off until 65 d after disease onset. However, the lower 95% confidence interval (CI) for the mean ODC% was only above the manufacturer's cut-off between 7 and 17 d after onset of disease. The CI of the “systemic” and “none” groups did not overlap at any time between the day of disease onset and 65 d after disease onset, and the estimated mean ODC% for both the “nonspecific” and “none” groups were generally below the cut-off for the majority of the study period. In conclusion, the serum antibody responses were highly dynamic and showed a high level of variation between individual cows. This strongly suggests that serology is unlikely to be useful for individual diagnosis of M. bovis-associated disease in dairy cows. However, it might still be useful for herd- or group-level diagnosis. Antibodies in milk were only increased in cows with M. bovis mastitis, indicating that milk antibody measurements only have diagnostic utility for cows with mastitis. 相似文献
87.
《Food Control》2016
The assessment of wine traceability and authenticity is a major concern that has gained a lot of interest internationally since the wine has always been subjected to various fraudulent practices. Practiced since ancient times, wine fraud has become more sophisticated in the present day, taking many forms. Consumers, regulatory bodies and manufacturers are all interested to have reliable analytical tools and information to allow the authentication and detection of wine adulteration or incorrect labelling. This research study evaluates and proposes a possible strategy for the detection of adulterated sweet or medium sweet red table wines using appropriate chemical parameters which can reveal prohibited practices in the winemaking process. The work is performed on 29 table wine samples, bought from the market, packed in PET bottles. Exogenous addition of sugar and water in the counterfeited table red wines was detected by the measurement of stable isotopes content (δ13C and δ18O) known as origin markers and supplementary confirmed by other classical parameters, as the alcoholic strength of the wines (‰ vol.) and the presence of 5-(hydroxymethyl)-2-furaldehyde (HMF) and of synthetic sweeteners or synthetic red dyes used to correct deficiencies of taste and colour. Additionally, the nature and profile of anthocyanins, as indicator of the red colour of wine, was investigated in the table wines and then compared with that of authentic wines obtained by microvinification of Vitis vinifera, in order to determine their authenticity. 相似文献
88.
本文从总体架构、业务流程、网络架构、关键点设计这几个建设要点进行阐述,介绍了贵州广播电视台的播出建设思路;同时通过引入4K播出、IP化、超融合架构、全媒体发布等前沿技术,进行对未来播出技术架构的展望。 相似文献
89.
K值是衡量建筑经济性的重要指标,整体化教学楼群的K值普遍偏低,需要进行优化研究.通过分析影响整体化教学楼群K值的因素,建立理论模型,对四类单元模式的K值进行量化分析,并提出了整体化教学楼群的K值优化策略及适宜范围. 相似文献
90.
《爱丽丝梦游仙境》采用了多种拍摄和制作技术,并且这些技术与技巧结合得非常好,给观众带来了一场非常完美的视听盛宴。本文主要介绍该片制作方案的确定、摄影器材的选择、为合成所作的准备、绿幕前拍摄和布光技巧、形象化预审视以及前后期如何完美结合实现2D转3D等制作技术与技巧等,并简要探讨现代电影制作中摄影师的职责和变化。 相似文献