• 제목/요약/키워드: Consumption utility

검색결과 228건 처리시간 0.029초

IEEE 802.11b Infrastructure 환경에서 저전력 통신을 위한 전송 전력 제어 기법 (A Transmit Power Control Method for Low-Power Communication in 802.11b Infrastructure Networks)

  • 권도한;정희록;박창윤;정충일
    • 한국정보과학회논문지:정보통신
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    • 제32권2호
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    • pp.180-189
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    • 2005
  • 본 논문에서는 802.11b 무선 LAN환경에서 전송 전력을 제어함으로써 통신에 소비되는 전력을 절약할 수 있는 방법을 제안한다. 먼저 실험을 통해 전송 전력의 조절이 성능과 전력 소비 면에서 미치는 영향을 조사하였다. 이를 기초로 하여 TCP의 혼잡 제어 기법과 유사하게 재전송 비율을 암시적인 피드백으로 사용하여 단계적으로 적정 전송 전력을 찾는 방법을 제안하였다. 제안한 방법은 리눅스 시스템에서 구현하여 실험을 하였으며, 실험 결과를 통해 제안한 전송 전력 제어 방법의 타당성 및 실효성을 보였다. 제안한 방법은 통신 성능의 저하 없이 전송 전력을 제어함으로써 전력 소비를 줄일 수 있었다

이부요금제하에서의 매몰비용오류에 관한 실증연구 (An Empirical Study on Sunk-Cost Fallacy under the Two-Part Tarriff)

  • 이상우;고창열;최선미;박준호
    • 한국통신학회논문지
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    • 제36권10B호
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    • pp.1192-1199
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    • 2011
  • 본 논문의 목적은 기본료와 통화료로 구성되어 있는 이동통신서비스의 이부요금제 (two-part tarriff) 방식에서 대표적인 인식편향(Cognitive Bias) 중 하나인 매몰비용오류(sunk cost fallacy) 행위의 발생 여부를 실증적으로 분석하고, 매몰비용오류 발생 최소화를 위한 바람직한 요금제 개선방안을 제시하는 것이다. 분석결과 이용자들은 매몰비용오류에 의해 기본료를 높게 지불할수록 자신의 최적소비량보다 많은 통화량을 발생시킴으로써 보다 많은 통신비를 지출한다. 따라서 기본료 인하는 매몰비용오류 효과를 감소시킴으로써 소비자들로 하여금 자신의 효용함수에 따라 최적 소비량에 근접한 통화량을 발생시키도록 유도할 수 있다.

Zigbee Protocol을 이용한 감시용 Camera Control System 설계 (Design of System for Control of Surveillance Camera with the Zigbee)

  • 민철;김영길
    • 한국정보통신학회:학술대회논문집
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    • 한국해양정보통신학회 2005년도 추계종합학술대회
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    • pp.939-942
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    • 2005
  • 감시용 카메라의 기능이 다양화 됨에 따라 컨트롤러나 PC로 통신을 이용하여 감시용 카메라를 제어할 필요가 생겼다. 이를 해결 할 수 있는 방안으로는 무선 통신과 유선 통신이 있다. 하지만 유선통신은 별도의 선을 사용해야 한다는 단점이 있다. 그리고 현재 많이 보편화된 Bluetooth를 이용한 무선 통신은 전력 소모가 크다는 단점이 있다 반면 Zigbee 프로토콜을 이용한 무선통신은 Bluetooth보다 전력 소모가 적고 데이터 전송의 신뢰성이 좋다는 장점을 가지고 있다. 이에 프로토콜을 이용한 감시용 카메라 제어 시스템을 설계하였다.

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Multi-homing in Heterogeneous Wireless Access Networks: A Stackelberg Game for Pricing

  • Lee, Joohyung
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제12권5호
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    • pp.1973-1991
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    • 2018
  • Multimedia applications over wireless networks have been evolving to augmented reality or virtual reality services. However, a rich data size compared to conventional multimedia services causes bandwidth bottlenecks over wireless networks, which is one of the main reasons why those applications are not used widely. To overcome this limitation, bandwidth aggregation techniques, which exploit a multi-path transmission, have been considered to maximize link utilization. Currently, most of the conventional researches have been focusing on the user end problems to improve the quality of service (QoS) through optimal load distribution. In this paper, we address the joint pricing and load distribution problem for multi-homing in heterogeneous wireless access networks (ANs), considering the interests of both the users and the service providers. Specifically, we consider profit from resource allocation and cost of power consumption expenditure for operation as an utility of each service provider. Here, users decide how much to request the resource and how to split the resource over heterogeneous wireless ANs to minimize their cost while supporting the required QoS. Then, service providers compete with each other by setting the price to maximize their utilities over user reactions. We study the behaviors of users and service providers by analyzing their hierarchical decision-making process as a multileader-, multifollower Stackelberg game. We show that both the user and service provider strategies are closed form solutions. Finally, we discuss how the proposed scheme is well converged to equilibrium points.

염화암모늄 영향에 따른 혼합종 메탄산화균의 종조성 변화 및 메탄올 대사 특성 (Effect of Ammonium Chloride on the Mixed Methanotrophs Species Composition and Methanol Metabolism)

  • 김이태;윤영한
    • 한국수처리학회지
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    • 제26권6호
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    • pp.27-42
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    • 2018
  • This study analyzed the utility of ammonium chloride ($NH_4Cl$) as a nitrogen source for methanotroph communities. When cultured in nitrate mineral salt (NMS) medium, the methanotroph community we identified four families, seven genera, and 16 type I and type II species of methanotrophs. Among species in the Methylobacter genus, Methylobacter marinus could be actively cultured in NMS medium without NaCl addition. Following the addition of 25 mM $NH_4Cl$, the numbers of the type I genera Methylomonas, Methylococcus, and Methylobacter were increased, whereas the numbers of the type II genera Methylocystis and Methylosinus were decreased after 5 days. In methanotroph communities, certain concentrations of $NH_4Cl$ affected methane consumption and growth of methanotrophs at the community level. $NH_4Cl$ caused a considerable decrease in the methane consumption rate and the expression of soluble methane monooxygenases (sMMOs) but did not inhibit the growth of Methylomonas methanica expressing sMMO. These results could be attributed to competitive antagonism of MMOs due to their direct involvement in ammonia oxidation.

Digital Twin based Household Water Consumption Forecasting using Agent Based Modeling

  • Sultan Alamri;Muhammad Saad Qaisar Alvi;Imran Usman;Adnan Idris
    • International Journal of Computer Science & Network Security
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    • 제24권4호
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    • pp.147-154
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    • 2024
  • The continuous increase in urban population due to migration of mases from rural areas to big cities has set urban water supply under serious stress. Urban water resources face scarcity of available water quantity, which ultimately effects the water supply. It is high time to address this challenging problem by taking appropriate measures for the improvement of water utility services linked with better understanding of demand side management (DSM), which leads to an effective state of water supply governance. We propose a dynamic framework for preventive DSM that results in optimization of water resource management. This paper uses Agent Based Modeling (ABM) with Digital Twin (DT) to model water consumption behavior of a population and consequently forecast water demand. DT creates a digital clone of the system using physical model, sensors, and data analytics to integrate multi-physical quantities. By doing so, the proposed model replicates the physical settings to perform the remote monitoring and controlling jobs on the digital format, whilst offering support in decision making to the relevant authorities.

SUV 차량 리어 스포일러 최적 형상에 관한 연구 (A Study on the Optimum Design of SUV Rear Spoiler)

  • 박동규
    • 한국산학기술학회논문지
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    • 제19권2호
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    • pp.689-694
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    • 2018
  • 최근 친환경 자동차 개발과 함께 대기 오염 문제 대응을 위해서 자동차 연비 개선은 차량 개발에 있어서 매우 중요하다. 개발 차량의 연비 향상을 위한 요소 중 차량 외관을 타고 흐르는 공기 흐름과 차량 후부에서의 공기 유동 현상은 중요한 요소이다. 특별히 SUV(Sports Utility Vehicle) 차량의 차량 후부 공기 유동은 리어 스포일러 설계 시 고려해야 하는 중요한 설계 항목 중 하나이다. 본 연구에서는 차량의 공기 유동에 영향을 주는 리어 스포일러의 제어 인자를 정하고 각 제어 인자의 공기 유동 특성에 대한 민감도를 시험을 통하여 비교 분석하고, 유동 저항력을 감소시킬 수 있는 스포일러의 최적 제어 인자를 결정하였다. 결정된 최적 제어 인자를 이용한 시험 모델을 만들어 시험평가하고 그 결과 값에 대한 S/N비와 평균값을 분석하여 제어 인자 값을 변경하였다. 변경된 최적 제어 인자 값을 이용한 개선 모델을 다시 제작하고 유동 시험을 실시하여 공기 저항력 감소 효과와 원가절감 효과를 확인하였다.

Why Genuine Luxury Brands Are Consumed? Counterfeits? Examining Consumer Identification

  • Suh, Hyunsuk
    • Asia Marketing Journal
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    • 제14권3호
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    • pp.69-102
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    • 2012
  • Owing to increased number of luxury brand users, both genuine and counterfeit luxury product consumption continues to increase every year. Luxury brand is defined as use or display of a particular branded products which brings the ownership prestige apart from its functional utility(Grossmand and Shapiro 1988). Some luxury brands have imitations sold in marketplace due to their popularity. These imitations or counterfeits have been jumping on the bandwagon of the upturn in sales of their originals. The purpose of our study is to understand consumer's underlying motives to consume luxury brands, genuine and or counterfeits. To do this, we propose functional theories of attitudes, decision-making styles, and life attitudes to form the determining causes for different consumption choices of luxury brands: genuine brands, counterfeit brands, both genuine and counterfeit brands, and no consumption on luxury brands types. In proposed causal pathways, we examine moderated effects of socio-psychological factors to further investigate if consumer profiles would exert influences in causal relationships. From the existing theories of functional attitudes: value-expressive and social-adjustive attitudes, we developed and introduced a new measure of rationality-consumptive attitude. From the existing eight decision-making characteristics of consumer styles inventory(CSI), three measures of high-quality, hedonic-shopping, and price-shopping styles were primarily applied in the study along with newly introduced measure of 'high-price' being added, which makes four total. Seven life attitude measures of life purpose, life control, will to meaning, goal seeking, future mean to fulfill, life satisfaction, and religiosity were applied. Finally, such socio-psychological measures as age, gender, marital status, income, and age-gap between couples were assumed to function as moderators. With 430 valid study samples, ages from 20s to 50s, with more females(316) than males(114), with average personal possessions of 5 genuine and 9 counterfeit luxury brands, we conducted questionnaire survey. Results indicated that social-adjustive function is totally disappeared in the relationship due to current social trend of widespread consumptions on both genuine and counterfeit brands which in turn, make consumers feel less special on wearing or carrying them unlike in the past. Self-expressive function and rationality-consumptive functions act as strong catalysts for genuine brand consumption and counterfeit brand consumption, respectively. On consumers' decision-making styles, high-price sublation is the most powerful indicator anticipating counterfeit consumption, even more powerful than personal incomes. In life attitude, the overall model fit was not validated, and only life control and life satisfaction are proven to be significant on both genuine and counterfeit product consumptions. Employment of socio-psychological factors in the model improved understanding of users further. Young consumers tend to go for genuine products over counterfeits. Consumers in different income groups; low, medium and high, all significantly consume genuine products for reasons of different decision-making styles. The results indicated that consumers whose personal disposition is predisposed to consume products in the form of reflection of his or her personality, go only for genuine brands for quality reason, while consumers who rationally consume products for its function or usability, go only for counterfeits for high-price sublation reason. Meanwhile, both product users support for high-price orientation who are not well off.

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Photovoltaic Micro Converter Operated in Boundary Conduction Mode Interfaced with DC Distribution System

  • Seo, Gab-Su;Shin, Jong-Won;Cho, Bo-Hyung;Lee, Kyu-Chan
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2011년도 추계학술대회
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    • pp.44-45
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    • 2011
  • Research on photovoltaic (PV) generation is taking a lot of attention due to its infinity and environment-friendliness with decrease of price per PV cell. While central inverters connect group of PV modules to utility grid in which maximum power point tracking (MPPT) for each module is difficult, micro inverter is attached on each module so that MPPT for individual modules can be easily achieved. Moreover, energy generation and consumption efficiency can be much improved by employing direct current (DC) distribution system. In this paper, a digitally controlled PV micro converter interfacing PV to DC distribution system is proposed. Boundary conduction mode (BCM) is utilized to achieve zero voltage switching (ZVS) of active switch and eliminate reverse recovery problem of passive switch. A 120W prototype boost PV micro converter is implemented to verify the feasibility and experimental results show higher than 98% efficiency at peak power and 97.29% of European efficiency.

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대구시 하수처리장 운전실태에 따른 중수도 도입 방안 연구 (A Research for Introduction of Graywater Facility on Analysis of Actual Conditions of Sewage Treatment Plant in Daegu City)

  • 최미영;나욱호;홍원화;김삼열
    • 한국주거학회논문집
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    • 제16권1호
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    • pp.27-35
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    • 2005
  • It has seen the significant increase of water consumption rate due to rapid industrialization, high-densities of city, and increasing the population; thereby leads further water resource required in near future. In order to solve this deficit there are one of solution that gray water method demonstrates advantages regarding the questions of optimal water utility and thereby master plan of water. The method of study is analysis of investigation data through interview and research of sewage treatment plants in Daegu City. Through these analysis, this paper examines the capacity of graywater and optimal graywater facility.