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51.
Concomitant to the liberalisation policy and market reforms in India has been the issue of declining budgetary support for public sector organisations. Hitherto, Indian Railways, the biggest publicly-owned enterprise, has largely been supported by the exchequer. Since the early 1990s, however, the Railways has had to operate increasingly as a commercial rather than a social organisation. One of the ways of improving efficiency is to introduce efficiency-enhancing technologies. This paper is a case study of the introduction of paging technology to the Ratlam Division of Indian Railways. It describes the process of planning and implementation, the HRM implications of the adoption and how the process was successfully managed. It aims at shedding further light on the nature and the processes whereby technologies eventually gain company recognition and acceptance. 相似文献
52.
Ajit Chaturvedi 《Microelectronics Reliability》1997,37(6):943-948
The sequential procedure developed by Govindarajulu and Sarkar [Sequential estimation of scale parameter in exponential distributions with unknown location. Utilitas Math.40, 161–178 (1991)] for estimating the scale parameter of an exponential distribution, when the location parameter is unknown, is further analyzed. Generalizing the results of Govindarajulu and Sarkar, the ‘asymptotic risk-efficiency’ of the sequential procedure is established for the general loss function. A simple method of obtaining the asymptotic distribution of the stopping time is given. For the case of quadratic loss function and linear cost of sampling, a much simpler proof for obtaining the second-order approximations for the risk is provided. 相似文献
53.
54.
Fei Yang Stella Raynova Ajit Singh Qinyang Zhao Carlos Romero Leandro Bolzoni 《JOM Journal of the Minerals, Metals and Materials Society》2018,70(5):632-637
Powder metallurgy is a very attractive method for producing titanium alloys, which can be near-net-shape formed and have freedom in composition selection. However, applications are still limited due to product affordability. In this paper, we will discuss a possible cost-effective route, combining fast heating and hot processing, to produce titanium alloys with similar or even better mechanical properties than that of ingot metallurgy titanium alloys. Two titanium alloys, Ti-5Al-5V-5Mo-3Cr (Ti-5553) and Ti-5Fe, were successfully produced from HDH titanium powder and other master alloy powders using the proposed processing route. The effect of the processing route on microstructural variation and mechanical properties have been discussed. 相似文献
55.
In wavelength routed optical networks, the number of wavelength channels is limited due to several constraints and each wavelength
as well as each lightpath support traffic in the Gbps range. On the other hand, the traffic requested by an individual connection
is still in the Mbps range. Therefore, to utilize the network resources (such as bandwidth and transceivers) effectively,
several low-speed traffic streams have to be efficiently groomed or multiplexed into one or more high-speed lightpaths. The
grooming problem of a static demand is considered as an optimization problem. In this work, we have investigated the traffic
grooming problem with the objective of maximizing the network throughput for wavelength-routed mesh networks and map this
problem to the clique partitioning problem. We have proposed an algorithm to handle general multi-hop static traffic grooming
based on the clique partitioning concept. The efficiency of our approach has been established through extensive simulation
on different sets of traffic demands with different bandwidth granularities for different network topologies and compared
the approach with existing algorithms. 相似文献
56.
Polyaniline salt was synthesized through the chemical oxidation of aniline with sodium persulfate as the oxidant and didecyl ester of 4‐sulfophthalic acid via three different polymerization pathways (aqueous, emulsion, and interfacial). In these polymerization processes, the ester acted as a novel plast dopant and as an emulsifier. The yield, conductivity, and number of ester units present in the polyaniline salts were determined. A polyaniline salt prepared by emulsion polymerization was soluble in chloroform and showed excellent solution‐processing properties. Polyaniline samples prepared by aqueous or interfacial polymerization were not soluble in chloroform. A soluble polyaniline salt was successfully synthesized through the washing of an organic layer containing the polyaniline salt with water in emulsion polymerization. X‐ray diffraction spectra of polyaniline salts prepared by the three different methods showed an ordered, layer‐type supramolecular structure. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 相似文献
57.
提出能够鉴别损伤位置和截面损伤严重程度的钢框架非比例破坏监测方法。所提出的方法由两部分组成,一是损伤识别,二是损伤严重程度分析。损伤识别和严重程度分析均以结构动力性质的变化作为损伤的判据,以此来确定损伤位置和严重程度。所提方法中损伤判别的重要特点是能够在损伤严重程度分析之前,精确地区分不同的损伤区域。与整个结构尺寸相比,损伤区域相对较小,因此,确定损伤严重程度的计算量更小。检测方法的另一个特点是有些特征值或振型对噪声相对不敏感。采用所提检测方法对几个框架进行验证,结果表明,该方法能够成功地检测及量化截面的损伤。 相似文献
58.
In the present study, the effects of soybean biodiesel (SB)–diesel blends containing 1% strontium (Sr) doped zinc oxide (ZnO) nanoparticles (NPs) on the performance and emission parameters of a variable compression ratio (VCR) engine were investigated. To make the fuel blends, 25% soybean biodiesel (SB25) was added to the diesel. To improve the blend's stability, Sr/ZnO NP additions were blended with SB25 at 50 and 75 ppm utilizing an ultrasonication method and a surfactant at 2%. Various physicochemical techniques, such as X-ray diffraction, field-emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, and ultraviolet spectroscopy, were used to characterize the produced NPs. These blends improved overall engine characteristics when used with a VCR. In comparison to the absence of nanoadditives, the brake thermal efficiency increased by 10.37% and the brake-specific fuel consumption decreased by 16.76% while using 50 ppm Sr/ZnO NPs additive in SB25 (SB25Sr/ZnO50). In addition, the presence of Sr/ZnO in SB25 results in lower harmful emissions such as hydrocarbon, CO, CO2, and smoke, which are reduced by 11.20%, 13.81%, 41.43%, and 21.34%, respectively, when compared to SB25 fuel. The Sr/ZnO NPs in the blend are an excellent choice for improving engine emission and performance. 相似文献
59.
Phytoplankton as biomonitors: A study of Museum Lake in Government Botanical Garden and Museum,Thiruvananthapuram, Kerala India 下载免费PDF全文
An assessment of the pollution status of Museum Lake in the Thiruvananthapuram Botanical Garden and Museum was conducted. Analysis of different community structures of the planktonic taxa in the lake revealed it is organically polluted, attributable to the organic litter from riparian vegetation. A total of 30 most pollution‐tolerant phytoplankton genera and 24 pollution‐tolerant species were identified. Pollution‐tolerant phytoplankton genera in the lake included Chlorophyceae, Bacillariophyceae, Cyanophyceae and Euglenophyceae. Scenedesmus, Pinnularia, Euglena, Ankistrodesmus, Closterium, Crucigenia, Kirchneriella, Merismopedia and Oscillatoria were some of the phytoplankton pollution tolerant genera whereas, Nitzschia palea, Synedra acus, Scenedesmus quadricauda, Pandorina morum and Trachelomonas volvocina were some of the pollution tolerant species noted. Excessive nutrient loading from the surrounding area is definitely degrading the quality of this urban lake ecosystem. Detailed information regarding the pollution status of a waterbody is very important in this regard, noting it ultimately assists in undertaking proper management of a waterbody. The Palmer Algal Index score for Museum Lake was 37, indicating it is highly organic enriched. The results of different algal indices (e.g. Chlorophycean Index; Nygaard Index) indicated a eutrophic condition for Museum Lake, being attributed to its increased organic enrichment. Canonical correspondence analysis between environmental variables and the microalgal bioindicators also highlighted the influence of the physical and chemical parameters on phytoplankton abundance and distribution in Museum Lake. 相似文献
60.
Climate change impacts on natural resources and communities: A geospatial approach for management 下载免费PDF全文
Adikanda Ojha Ajit Kumar Pattnaik Jajnaseni Rout 《Lakes & Reservoirs: Research and Management》2018,23(1):34-42
Climate change causes environmental depletion, with threats to the global economy. The health and productivity of ecosystems underpin agriculture, with stable ecosystems being the foundation for economic livelihoods and food security. This study proposes adaptation measures, using geospatial technology, for conserving natural resources and improving livelihoods of the local community from climate change scenarios. Planning, policy decisions and resultant programmes are required for natural resource management, which must be based on broad citizen participation and the engagement of rural communities. The suggested adaptation measures will help the planning system to regulate development of natural resources and the socio‐economic environment. The major natural resources in the environment are land and water, both of which can be severely degraded by human interventions, as well as climate change. Various thematic maps are prepared with the use of geospatial technology, in order to be helpful for site‐suitability analysis directed to the preparation of land and water management action plans for socio‐economic development. The study area is a micro‐watershed of the catchment of Ansupa Lake in the Cuttack District of Odisha, India. To reduce climate change impacts on natural resources and economic livelihoods, some adaptation measures have been proposed (e.g., 68.9 ha for afforestation.; 13.94 ha for gap plantations and agro‐horticulture; 389.62 ha for farm ponds and renovation of existing ponds for pisciculture and duckery activities, etc.; 11.33 ha for land management, along with five bore wells, eight dug wells, 51 LBS/check dams, and four WHSs, etc., for water management for sustainable use). 相似文献