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排序方式: 共有691条查询结果,搜索用时 15 毫秒
111.
Ankur Chaudha Rajeev Jain A. R. Singh P. K. Mishra 《The International Journal of Advanced Manufacturing Technology》2011,53(5-8):689-698
Viability of a product or service in the market depends upon the satisfaction that it can extend to its customers through quality. Quality function deployment (QFD) is a tool that gathers voice of customer (VoC) and inducting the expected features in the final product. It is also desirable that the practitioners of QFD must extend due importance to latent expectations of the customers, which in turn may fulfill overall customer satisfaction for a product or service. Kano et al. (J Jpn Soc Qual Control, 14:39–48, 1984; 1996) and Kano (2001) have suggested a method to identify the different categories of requirements through customer responses. Based on the QFD and Kano model analysis, a function has been proposed to adjust the traditional improvement ratio (Tan and Shen, Total Qual Manag 11:1141–1151, 2000) for each product or service attribute to recognize the importance of a attribute, which can be helpful in developing a product or service in such a manner that maximum customer satisfaction can be achieved. The proposed methodology has been illustrated using customer survey data. 相似文献
112.
Richa Mishra Vivekanand Jha Rajeev K. Tripathi Ajay K. Sharma 《Wireless Personal Communications》2018,99(2):651-680
Energy consumption is one of the important issues in wireless sensor network that rely on non chargeable batteries for power. Also, the sensor network has to maintain a desired sensing coverage area along with periodically sending of the sensed data to the base station. Therefore, coverage and the lifetime are the two important issues that need to be addressed. Effective deployment of wireless sensors is a major concern as the coverage and lifetime of any wireless sensor network depends on it. In this paper, we propose the design of a Probability Density Function (PDF) targeting the desired coverage, and energy efficient node deployment scheme. The suitability of the proposed PDF based node distribution to model the network architecture considered in this work has been analyzed. The PDF divides the deployment area into concentric coronas and provides a probability of occurrence of a node within any corona. Further, the performance of the proposed PDF is evaluated in terms of the coverage, the number of transmissions of packets and the lifetime of the network. The scheme is compared with the existing node deployment schemes based on various distributions. The percentage gain of the proposed PDF based node deployment is 32\(\%\) more than that when compared with the existing schemes. Thus, the simulation results obtained confirm the schemes superiority over the other existing schemes. 相似文献
113.
Rajeev Kumar Ranjan Kaushik Mazumdar Ratnadeep Pal Satish Chandra 《Analog Integrated Circuits and Signal Processing》2017,92(1):15-27
This paper presents a self-generating square/triangular wave generator using only the CMOS Operational Transconductance Amplifiers (OTAs) and a grounded capacitor. The output frequency and amplitude of the proposed circuit can be independently and electronically adjusted. The proposed circuit validates its advantage by consuming less amount of power, which is about 71.3 µW. The theoretical aspects are authentically showcased using the PSPICE simulation results. The performance of the proposed circuit is also verified through pre layout and post layout simulation results using the 90 nm GPDK CMOS parameters. A prototype of this circuit has been made using commercially available IC CA3080 for experimental verification. Experimentation also gives the similar output as per the theoretical proposition. The designed circuit is also made applicable to perform pulse width modulation (PWM). 相似文献
114.
Adsorptive studies of hazardous dye Tropaeoline 000 from an aqueous phase on to coconut-husk 总被引:1,自引:0,他引:1
This contribution presents result pertaining to the adsorptive removal of water-soluble hazardous dye Tropaeoline 000, on to a low cost adsorbent-coconut-husk and its efficiency in the dye colour sorption was compared with activated carbon (AC). The results obtained from the batch experiments revealed the ability of the coconut-husk to remove the Tropaeoline 000 dye. The adsorption of dye was carried out at different pH, temperatures, amount of adsorbent, contact time, concentration of adsorbate (initial dye concentration) and particle size. The adsorption studies revealed that the ongoing adsorption validates both Langmuir and Freundlich adsorption isotherm at temperatures 30, 40 and 50 degrees C. The adsorption isotherm data was also employed to calculate thermodynamic parameters like DeltaG degrees , DeltaH degrees and DeltaS degrees . The negative values of DeltaG degrees indicate that the dye adsorption process is a spontaneous in nature. The positive value of DeltaH degrees shows the endothermic nature of AC/coconut-husk system whereas negative value of DeltaH degrees indicates that the exothermic nature of AC/coconut-husk. The adsorption was found to undergo via a pseudo-second order adsorption kinetics and the results revealed that coconut-husk, an agricultural waste, proved to be an excellent low cost adsorbent. 相似文献
115.
Density functional theory is used to show that the adhesion between single-walled carbon nanotubes (SWNTs) and the catalyst particles from which they grow needs to be strong to support nanotube growth. It is found that Fe, Co, and Ni, commonly used to catalyze SWNT growth, have larger adhesion strengths to SWNTs than Cu, Pd, and Au and are therefore likely to be more efficient for supporting growth. The calculations also show that to maintain an open end of the SWNT it is necessary that the SWNT adhesion strength to the metal particle is comparable to the cap formation energy of the SWNT end. This implies that the difference between continued and discontinued SWNT growth to a large extent depends on the carbon-metal binding strength, which we demonstrate by molecular dynamics (MD) simulations. The results highlight that first principles computations are vital for the understanding of the binding strength's role in the SWNT growth mechanism and are needed to get accurate force field parameters for MD. 相似文献
116.
Chris P. Pantelides Rajeev Surapaneni Lawrence D. Reaveley 《Canadian Metallurgical Quarterly》2008,12(5):570-576
Precast/prestressed concrete sandwich panels consist of two concrete wythes separated by a rigid insulation foam layer and are generally used as walls or slabs in thermal insulation applications. Commonly used connectors between the two wythes, such as steel trusses or concrete stems, penetrate the insulation layer causing a thermal bridge effect, which reduces thermal efficiency. Glass fiber-reinforced polymer (GFRP) composite shell connectors between the two concrete wythes are used in this research as horizontal shear transfer reinforcement. The design criterion is to establish composite action, in which both wythes resist flexural loads as one unit, while maintaining insulation across the two concrete wythes of the panel. The experiments carried out in this research show that hybrid GFRP/steel reinforced sandwich panels can withstand out-of-plane loads while providing resistance to horizontal shear between the two concrete wythes. An analytical method is developed for modeling the horizontal shear transfer enhancement using a shear flow approach. In addition, a truss model is built, which predicts the panel deflections observed in the experiments with reasonable accuracy. 相似文献
117.
Deepankar Choudhury Rajeev Kumar Bharti Siddharth Chauhan Buddhima Indraratna 《Canadian Metallurgical Quarterly》2008,134(10):1558-1563
For an efficient and economical design of a railway track system, it is necessary to understand the behavior of each track component with special reference to ballast and subgrade, which play a pivotal role in distributing the large, cyclic wheel loads longitudinally, laterally, and vertically away from the wheel contact area on the rail surface to the underlying soil strata. This paper presents an analytical model of a track-ballast-subgrade system with different formation soils such as dense uniform sand, stiff clay, loose sand, and soft clay modeled by using a mass-spring dashpot system with two degrees of freedom. This represents the varying energy distribution through ballast and subgrade in the vertical direction. Results are presented in the form of time-displacement response profiles for both the ballast and subgrade layers. In addition, the magnification factors for displacements with variation in subgrade soils for cyclic loading frequencies are reported. It is observed that the results obtained from the present analysis follow the experimentally observed trends already available in the literature. 相似文献
118.
Ramchand Rajeev; Marshall Grant N.; Schell Terry L.; Jaycox Lisa H. 《Canadian Metallurgical Quarterly》2008,76(4):668
This study examines the cross-lagged relationships between posttraumatic distress symptoms and physical functioning, using a sample of 413 persons who were hospitalized for injuries resulting from community violence. Posttraumatic distress was assessed at 1 week, 3 months, and 12 months postinjury, and posttraumatic physical functioning was assessed at 3 months and 12 months. Structural equation modeling was used to assess the prospective relationship between posttraumatic distress symptoms and physical functioning while controlling for demographic characteristics and objective measures of injury severity. Results indicate that posttraumatic distress and physical functioning are reciprocally related. Individuals with high levels of psychological distress at 1 week posttrauma have worse physical functioning at 3 months. Psychological distress at 3 months was not significantly associated with subsequent change in physical functioning at 12 months. Individuals with poor physical functioning at 3 months had higher than expected levels of psychological distress at 12 months. These findings demonstrate a reciprocal relationship between physical and mental health following traumatic injury. Interventions targeting physical recovery may influence subsequent mental health, and therapies aimed at improving early mental health may also have long-term benefits for physical recovery. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
119.
120.
Intikhab A. Ansari V. P. S. Awana Rajeev Rawat M. Shahabuddin M. Husain H. Kishan A. V. Narlikar 《Journal of Materials Science》2007,42(15):6306-6309
We report fluctuation-induced conductivity (FIC) of the polycrystalline MgB2 superconductor in the presence of magnetic field. The results are described in terms of the temperature derivative of the resistivity, dρ/dT. The dρ/dT peak temperature observed for H = 0 Tesla at 39 K remains very distinct under applied fields of 6 Tesla and 8 Tesla at 22 and 20 K respectively. Aslamazov and Larkin (AL) equations are used to explain the anisotropic nature of the polycrystalline MgB2. The effective coherence length, ξ p (0) determined experimentally is 55.17 Å, which roughly matches with previously reported experimental work. 相似文献