• Title/Summary/Keyword: David operation

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A Survey of Energy Efficiency Optimization in Heterogeneous Cellular Networks

  • Abdulkafi, Ayad A.;Kiong, Tiong S.;Sileh, Ibrahim K.;Chieng, David;Ghaleb, Abdulaziz
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.10 no.2
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    • pp.462-483
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    • 2016
  • The research on optimization of cellular network's energy efficiency (EE) towards environmental and economic sustainability has attracted increasing attention recently. In this survey, we discuss the opportunities, trends and challenges of this challenging topic. Two major contributions are presented namely 1) survey of proposed energy efficiency metrics; 2) survey of proposed energy efficient solutions. We provide a broad overview of the state of-the-art energy efficient methods covering base station (BS) hardware design, network planning and deployment, and network management and operation stages. In order to further understand how EE is assessed and improved through the heterogeneous network (HetNet), BS's energy-awareness and several typical HetNet deployment scenarios such as macrocell-microcell and macrocell-picocell are presented. The analysis of different HetNet deployment scenarios gives insights towards a successful deployment of energy efficient cellular networks.

Efficient detectors for MIMO-OFDM systems under spatial correlation antenna arrays

  • Guerra, David William Marques;Fukuda, Rafael Masashi;Kobayashi, Ricardo Tadashi;Abrao, Taufik
    • ETRI Journal
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    • v.40 no.5
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    • pp.570-581
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    • 2018
  • This work analyzes the performance of implementable detectors for the multiple-input multiple-output (MIMO) orthogonal frequency division multiplexing (OFDM) technique under specific and realistic operation system conditions, including antenna correlation and array configuration. A time-domain channel model was used to evaluate the system performance under realistic communication channel and system scenarios, including different channel correlation, modulation order, and antenna array configurations. Several MIMO-OFDM detectors were analyzed for the purpose of achieving high performance combined with high capacity systems and manageable computational complexity. Numerical Monte Carlo simulations demonstrate the channel selectivity effect, while the impact of the number of antennas, adoption of linear against heuristic-based detection schemes, and the spatial correlation effect under linear and planar antenna arrays are analyzed in the MIMO-OFDM context.

Pulsed Actuator with Combined Plunger Made of Carbon Steel and Permanent Magnet

  • Dolezel, Ivo;Panek, David;Ulrych, Bohus
    • Journal of international Conference on Electrical Machines and Systems
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    • v.1 no.3
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    • pp.282-288
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    • 2012
  • A special pulsed electromagnetic actuator is presented whose plunger consists of two parts made of carbon steel and permanent magnet, respectively. The actuator exhibits a high holding force and small consumption of energy. The movement of the plunger is controlled by short current pulses. The static characteristics and other operation properties of the device are modeled numerically.

Control of Parallel Connected Three-Phase PWM Converters without Inter-Module Reactors

  • Jassim, Bassim M.H.;Zahawi, Bashar;Atkinson, David J.
    • Journal of Power Electronics
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    • v.15 no.1
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    • pp.116-122
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    • 2015
  • This paper presents a new current sharing control strategy for parallel-connected, synchronised three-phase DC-AC converters employing space vector pulse width modulation (SVPWM) without current sharing reactors. Unlike conventional control methods, the proposed method breaks the paths of the circulating current by dividing the switching cycle evenly between parallel connected equally rated converters. Accordingly, any inter-module reactors or circulating current control will be redundant, leading to reductions in system costs, size, and control algorithm complexity. Each converter in the new scheme employs a synchronous dq current regulator that uses only local information to attain a desired converter current. A stability analysis of the current controller is included together with a simulation of the converter and load current waveforms. Experimental results from a 2.5kVA test rig are included to verify the proposed control method.

A Study for the Possibility of Reducing the Size of Battery Position (포병진지 규모의 축소 가능성에 관한 연구)

  • Go Jae-Hong;Gang Seong-Jin
    • Journal of the military operations research society of Korea
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    • v.18 no.1
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    • pp.74-85
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    • 1992
  • Increasing the number of artillery units requires more deployment space in the field operation area. However, there is limited space available in FEBA due to mountainous terrains. Therefore most artillery units cannot occupy enough deployment space which is proposed in the field artillery mannual(FM) to maximize the firing-effectiveness and to minimize the enemy threat. This paper studies the problems of reducing the size of a battery deployment space being applied currently without decreasing the firing-effectiveness of the battery. The optimum size of a battery position is obtained by using Lemus and David's allocation model and Supper Quick II Model which produces the probability of kill data with various input data. The result shows that the battery deployment space can be reduced without decreasing the firing-effectiveness in the example problem.

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Roman Polansky's Tess: Aesthetics of Human Body and Capital (로만 폴란스키의 <테스>: 육체와 자본의 미학)

  • Kim, Bong Eun
    • English & American cultural studies
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    • v.9 no.1
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    • pp.71-90
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    • 2009
  • David Harris argues that mass media suppress counter-hegemonic factors in order to reach audience. According to Harris's theory, the success of the film "Tess" depends on its effective adaptation from Thomas Hardy's novel Tess of the D'Urbervilles (1891). Tess (1979), directed by Roman Polansky, casting Nastassia Kinski for Tess, was acclaimed as a professional and commercial success, awarded with various prizes. Hardy's aim at criticizing Victorian English social and moral standard through Tess appears obscure in Polansky's film which focuses on the aesthetics of human body and capital. Polanski's Tess with urban white beauty does not emerge victimized by poverty, which the late twentieth century audience under the capitalist umbrella may abhor. To examine his use of music, sound effect, visual images by means of camera operation—angles, distances, close-ups and frequent movements—light and color, and mythic elements in the film, show Polansky's sharp perception of his contemporary audience's desire and conscientious work upon it.

Cost-Effective Modular Electroeionization (EDI)

  • Tessier, David F.;Haas, William E.
    • Proceedings of the Membrane Society of Korea Conference
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    • 1997.06a
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    • pp.143-158
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    • 1997
  • Electrochemical deionization (EDI) offers continuous demineralization at higher water recovery rates (>90%), compared with mixed bed ion exchange, and without the use of chemical regenerants and the associated production of saline waste water. Although EDI technology has been used in some power generation applications, its wider application requires the satisfactory resolution of outstanding capital cost and performance issues. This paper reports on the field evaluation of a new cost-effective EDI technology in a power generation application. The E-Cell System$^{TM}$, which became commercially available in the fourth quarter of 1996, consists of a rugged, modular system, based on a new high-performance EDI stack. Starting in May 1996, a 100 gpm modular EDI pilot system, rated for operation at 100 psi, was evaluated at the TVA Brown's Ferry Nuclear Plant. The feed consisted of Reverse Osmosis (RO) permeate with a conductivity of 4-7 $\mu$S/cm. The pilot system reliably produced 17.8-18.0 M$\Omega$.cm water under design operating conditions, independent. Silica levels were reduced from ca. 50 ppb to 4 ppb, while TOC levels were reduced from ca. 120 ppb to 30 ppb.

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A Case Study of Shanghai Tang: How to Build a Chinese Luxury Brand

  • Heine, Klaus;Phan, Michel
    • Asia Marketing Journal
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    • v.15 no.1
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    • pp.1-22
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    • 2013
  • This case focuses on Shanghai Tang, the first truly Chinese luxury brand that appeals to both Westerners and, more recently, to Chinese consumers worldwide. A visionary and wealthy businessman Sir David Tang created this company from scratch in 1994 in Hong Kong. Its story, spanned over almost two decades, has been fascinating. It went from what best a Chinese brand could be in the eyes of Westerners who love the Chinese culture, to a nearly-bankrupted company in 1998, before being acquired by Richemont, the second largest luxury group in the world. Since then, its turnaround has been spectacular with a growing appeal among Chinese luxury consumers who represent the core segment of the luxury industry today. The main objective of this case study is to formally examine how Shanghai Tang overcame its downfall and re-emerged as one the very few well- known Chinese luxury brands. More specifically, this case highlights the ways with which Shanghai Tang made a transitional change from a brand for Westerners who love the Chinese culture, to a brand for both, Westerners who love the Chinese culture and Chinese who love luxury. A close examination reveals that Shanghai Tang has followed the brand identity concept that consists of two major components: functional and emotional. The functional component for developing a luxury brand concerns all product characteristics that will make a product 'luxurious' in the eyes of the consumer, such as premium quality of cachemire from Mongolia, Chinese silk, lacquer, finest leather, porcelain, and jade in the case of Shanghai Tang. The emotional component consists of non-functional symbolic meanings of a brand. The symbolic meaning marks the major difference between a premium and a luxury brand. In the case of Shanghai Tang, its symbolic meaning refers to the Chinese culture and the brand aims to represent the best of Chinese traditions and establish itself as "the ambassador of modern Chinese style". It touches the Chinese heritage and emotions. Shanghai Tang has reinvented the modern Chinese chic by drawing back to the stylish decadence of Shanghai in the 1930s, which was then called the "Paris of the East", and this is where the brand finds inspiration to create its own myth. Once the functional and emotional components assured, Shanghai Tang has gone through a four-stage development to become the first global Chinese luxury brand: introduction, deepening, expansion, and revitalization. Introduction: David Tang discovered a market gap and had a vision to launch the first Chinese luxury brand to the world. The key success drivers for the introduction and management of a Chinese luxury brand are a solid brand identity and, above all, a creative mind, an inspired person. This was David Tang then, and this is now Raphael Le Masne de Chermont, the current Executive Chairman. Shanghai Tang combines Chinese and Western elements, which it finds to be the most sustainable platform for drawing consumers. Deepening: A major objective of the next phase is to become recognized as a luxury brand and a fashion or design authority. For this purpose, Shanghai Tang has cooperated with other well-regarded luxury and lifestyle brands such as Puma and Swarovski. It also expanded its product lines from high-end custom-made garments to music CDs and restaurant. Expansion: After the opening of his first store in Hong Kong in 1994, David Tang went on to open his second store in New York City three years later. However this New York retail operation was a financial disaster. Barely nineteen months after the opening, the store was shut down and quietly relocated to a cheaper location of Madison Avenue. Despite this failure, Shanghai Tang products found numerous followers especially among Western tourists and became "souvenir-like" must-haves. However, despite its strong brand DNA, the brand did not generate enough repeated sales and over the years the company cumulated heavy debts and became unprofitable. Revitalizing: After its purchase by Richemont in 1998, Le Masne de Chermont was appointed to lead the company, reposition the brand and undertake some major strategic changes such as revising the "Shanghai Tang" designs to appeal not only to Westerners but also to Chinese consumers, and to open new stores around the world. Since then, Shanghai Tang has become synonymous to a modern Chinese luxury lifestyle brand.

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A Study on Effective Menu Management Using David V Pavesic's Method (파베직 분석 방법을 이용한 효율적 메뉴관리에 관한 연구)

  • 고범석
    • Journal of Applied Tourism Food and Beverage Management and Research
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    • v.16 no.2
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    • pp.17-31
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    • 2005
  • Recently, hotel industry has realized the importance of food and beverage sales for the profit maximization, and the focuses on restaurant management has been growing. Accordingly, menu management in the F/B department is one of the most key factors determining the success or failure of business. Therefore, in this study, entree menu items of french restaurant in the deluxe hotel was analysed with presently theorized model of menu analysis, classified into four menu items. Also it was analyzed how those classified menu items influence on sales, number of sold, food cost percentage, contribution margin And, proper ways was presented to make restaurant managers and menu planner in order to increase food operation sales through proper modifications and methods on various menu analysis matrix. In Pavesic's menu analysis method, all of menu items have impact on the sales, number of sold, contribution margin and Primes, Sleepers do so on the food cost. The finding of this study was that Pavesic's menu analysis is superior to menu analysis in terms of the sales, number of sold, food cost percentage, contribution margin. Therefore, Pavesic's menu analysis is useful and efficient method in order to conduct menu engineering.

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Options Study for the Neutralization of Elemental Sodium During the Pyroprocessing of Used Nuclear Fuel

  • Westphal, Brian;Tolman, David;Tolman, Kevin;Frank, Steven;Herrmann, Steve;Warmann, Stephen;Marsden, Kenneth;Patterson, Michael
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.18 no.2
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    • pp.113-118
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    • 2020
  • An options study was performed for the treatment of residual elemental sodium in driver plenums following the chopping operation during the pyroprocessing of used nuclear fuel. Given the pending availability of a multi-function furnace for distillation and consolidation operations in the Fuel Conditioning Facility, the furnace was considered for the processing of driver plenums. Although two options (oxidation and distillation) could be performed in the multi-function furnace, neither option has been developed sufficiently to date to warrant the use of the furnace for treatment operations. Thus, it was decided to defer the treatment of elemental sodium from driver plenums in the multi-function furnace until more developed technologies and/or furnaces become available. In the interim, storage of the plenums and characterization efforts are recommended.