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51.
The complex microwave impedance at 11.5 GHz was measured in the superconducting state of two well characterized heavy fermion single crystals, UPt 3 and UBe 13 . This microwave photon energy is about 30% and 20% of the zero-temperature energy gap, respectively, and is higher than previous measurements. The results for UBe 13 seem to be well described by the Mattis-Bardeen theory in the dirty-limit for a conventional superconductor. However, the behavior in UPt 3 deviates from this conventional theory even when paramagnetic impurity scattering effects are taken into account.  相似文献   
52.
Decades of anthropogenic pressure have harmed riverscapes throughout North America by degrading habitats and water quality and can result in the extirpation of sensitive aquatic taxa. Local stream restoration projects have increased in frequency, but monitoring is still infrequent. In 2010, Kickapoo Creek in East Central Illinois was subjected to a stream restoration project that included implementation of artificial riffles, riprap, scouring keys, and riparian vegetation. We monitored the restoration efforts for 6 years after the restoration through annual sampling efforts at restored and reference sites to determine changes in habitat and fish assemblage using standard habitat sampling and electrofishing techniques. We observed distinct temporal and spatial shifts in physico‐chemical parameters along with changes in fish community structure. Although biotic integrity remained moderately low in reference assemblages, restored reaches showed 3‐year delay in response to restoration, with biotic integrity positively linked to additional instream habitat and altered channel morphology. Larger substrate sizes, submerged terrestrial vegetation, and newly formed scour pools along with reduced siltation were found in the restored sites, in contrast to the reference sites. These changes resulted in increased species diversity, reduced number of opportunistic species and consequently an overall increase in health of fish communities. We also observed recruitment of habitat specialists and increase in species with reproductive strategies that rely on complex substrates. The results of this study highlight some of the complex dynamics driving reach‐scale restoration projects. We demonstrate the usefulness of structural restoration as a management tool to increase biotic integrity through long‐term alteration of critical habitat. The delay in the response of species to the restoration efforts emphasizes the need for long‐term continuous temporal and spatial monitoring.  相似文献   
53.
The Indus, Ganges and Brahmaputra river basins support 700 million people in Asia. The water resources are used for irrigation, drinking, industry, navigation and hydropower. This paper reviews the literature on the impact of climate change on the hydrological regime of these river basins and suggests that the different basins are likely to be affected in different ways. Climate change will have a marked affect on meltwater in the Indus Basin and may result in increased flood risk in the Brahmaputra Basin. The overall impact on annual discharge is likely to be low, but more studies are required to understand intra-annual changes and the impact of extreme events.  相似文献   
54.
The speed control of a three-phase squirrel cage induction motor by employing triacs in the lines which operate in the normal phase control mode is described. The inherent limitation of low circuit commutated (dv/dt), which makes the triac circuit somewhat unreliable, has been overcome by suitably designing the snubber circuit. The closed-loop speed regulation of the system is then investigated by employing digital phase-locked loop scheme. Compared to the conventional method with antiparallel SCR's and analog servo, the present scheme is somewhat simpler, more economical, and extreme precision in speed control is possible. A complete model of the speed control system has been designed and experimentally evaluated in the laboratory.  相似文献   
55.
The design and testing of a microcomputer-controlled powertrain for a hybrid (heat engine/electric) vehicle are described in this paper. The detailed control strategy used and its software implementation on the Intel 8086 microcomputer are discussed. The powertrain is made up of an electric motor, gasoline engine, automatic transmission with the torque converter removed, engine and electric motor clutches, and Hy-Vo transfer chains. The drive system has been installed in vehicles and tested on a chassis dynamometer. Test results show smooth shifting of the transmission and sequencing of the clutches in the different hybrid operating modes. The overall performance of the hybrid car is good, and driveability is comparable to a conventional automobile.  相似文献   
56.
Nepal's Ministry of Health began offering free lifetime hemodialysis (HD) in 2016. There has been a large growth in renal replacement therapy (RRT) services offered in Nepal since 2010, when the last known data on the subject was published. In 2016, 42 HD centers existed (223% increase since 2010) serving 1975 end stage renal disease patients (303% increase since 2010); 36 nephrologists were registered (200% increase since 2010), 12 were trained in transplantation, and 790 transplants had been performed to date. We estimate the incidence of end stage renal disease to be 2900 patients (100 per million population). With an annual cost of approximately US$2300 per dialysis patient, offering free dialysis could potentially cost the government US$6.7 million per year, suggesting that 2.1% of the annual health budget would be allocated to 0.01% of the population. The geographic zone surrounding the capital city, Kathmandu, contains 50% of HD centers, but only 14.5% of Nepal's population. Forty‐eight percent of the population lives within zones without HD service, therefore infrastructure challenges exist in providing equitable access to RRT. The aim of this article is to summarize the current statistics of RRT in Nepal.  相似文献   
57.
The preliminary analysis of agricultural water productivity (AWP) over India using satellite data were investigated through productivity mapping, water use (actual evapotranspiration (ETa)/effective rainfall (Reff) mapping and water productivity mapping. Moderate Resolution Imaging Spectroradiometer data was used for generating agricultural land cover (MCD12Q1 at 500 m), gross primary productivity (GPP; MOD17A2 at 1 km), and ETa (MOD16A2 at 1 km). Reff was estimated at 10 km using the United States Department of Agriculture soil conservation service method from daily National Oceanic and Atmospheric Administration Climate Prediction Center rainfall data. Six years’ (2007–2012) data were analysed from June to October. The seasonal AWP and rainwater productivity (RWP) were estimated using the ratios of seasonal GPP (kg C m?2) and water use (mm) maps. The average AWP and RWP ranges from 1.10–1.30 kg Cm?3 and 0.94–1.0 kg C m?3, respectively, with no significant annual variability but a wide spatial variability over India. The highest AWP was observed in northern India (1.22–1.80 kg C m?3) and lowest in western India (0.81–1.0 kg C m?3). Large variations in AWP (0.69–1.80 kg C m?3) were observed in Himachal Pradesh, Jammu and Kashmir, northeastern states (except Assam), Kerala, and Uttaranchal. The low GPP of these areas (0.0013–0.13 kg C m?2) with low seasonal total ETa (<101 mm) and Reff (<72 mm) making the AWP high that do not correspond to high productivity but possible water stress. Gujarat, Rajasthan, Maharashtra, Madhya Pradesh, Jharkhand, and Karnataka showed low AWP (0.73–1.13 kg C m?3) despite having high ETa (261–558 mm) and high Reff (287–469 mm), indicating significant scope for improving productivity. The highest RWP was observed in northern parts and Indo-Gangetic plains (0.80–1.6 kg C m?3). The 6 years’ analysis reveals the status of AWP, leading to appropriate interventions to better manage land and water resources, which have great importance in global food security analysis.  相似文献   
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Abstract:

This article extends the new product development (NPD) literature by presenting a case study of a lean product development (LPD) transformation framework implemented at a U.S. based manufacturing firm. In a departure from typical LPD methods, in this article the design structure matrix and the cause and effect matrix are integrated into the lean transformation framework, allowing analysis of the underlying complexity of a product development (PD) system, and thus facilitating determination of the root causes of wasteful reworks. Several strategies to transform the current PD process into a lean process are discussed. Besides the two-phase improvement plan, a new organizational structure roadmap and a human resources plan are also suggested to support the recommended changes in the NPD process. The results of the first phase show a 32% reduction in PD cycle time due to the proposed NPD process. The article concludes with lessons learned and implications for engineering managers based on the case study.  相似文献   
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