• 한국정보처리학회논문지
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• 제2권6호
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• pp.985-994
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• 1995

본 논문에서는 높은 시스템 가용성을 제공할 뿐만 아니라 고장 발생시 데이타 손실이 없는 두 가지 hot standby 구조를 제안한다. 제안된 hot standby 구조의 성능 을 평가하기 위해서 hot standby 구조로부터 동기 unit 만을 제거한 warm standby 구 조를 고려하였으며, 각 구조에 대한 시스템 불가동률을 마르코프 상태도를 이용하여 구한 후 서로 비교 평가하였다. 본 연구 결과, 대부분의 경우 hot standby 구조가 warm standby 구조보다 훨씬 높은 가동률을 제공하였으며, 외부 동기 unit로 구성된 hot standby 구조가 내부 동기 unit로 구성 된 hot standby 구조보다 향상 약간 높은 시스템 가동률을 유지하였다. 각 구조에 대한 active set time과 personnel recovery rate 는 시스템 가동률에 거의 영향을 미치지 않았다. 그러나 data recovery time 이 임계치 이상으로 증가하는 경우에는 hot standby 구조와 warm standby구조 모두 시스 템 가동률이 급격히 저하되었고 특히 hot standby 구조의 성능 저하가 심하여 궁극적으로 warm standby 구조보다 시스템 가동률이 떨어지는 현상을 보였다.

• 가정과삶의질연구
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• 제27권4호
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• pp.141-160
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• 2009

Recently, some policies for reducing standby power, which has quite an effect on electricity consumption, have been employed all over the world. This study surveys the present condition of standby power for major electric home appliances during three years and analyzes the result of technical development reducing standby power. It presents how the industry paid attention to applying the technique of reducing standby power to electric appliances and how it affects the product's energy efficiency. We survey the standby power's change for six items, which were selected from the major electric appliances available on the market. It analyzes the difference of standby power consumption between appliances with a standby power reducing technique and those without during the latest three years. The amount of the average standby power is also compared. The comparison data confirms that the industry's effort and application of reducing standby power contribution has contributed to increasing an appliance's energy efficiency. This study restricted the analyzed items to six appliances, which has been a low volunteered involvement in the standby power reducing program. It is important for reducing standby power consumption of appliances because it contributes to saving electric energy at home and abroad. The development of the standby power reducing technique is needed for more appliances. Along with the development of the standby power reducing technique in the industrial field, it also necessary for consumers to enlarge their understanding of standby power reduction for economic, social, and environmental values.

• 무역상무연구
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• 제12권
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• pp.495-518
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• 1999

Since the end of World War II, the standby letters of credit have been used as a surety device, serving as a performance bond and guarantee in the world. In Korea, the standby letters of credit have been also being used in international transactions. But there have been a few studies on the standby letters of credit. This study is carrying out to reveal the characteristics of the standby letters of credit and the documentary letters of credit and also between the standby letters of credit and guarantees. Secondly, this study is carrying out to indicate types of practical use of standby letters of credit in international transactions, i.e. bid bonds, performance bonds, advanced payment guarantees etc.. Finally, this study is carrying out to indicate governig rules regarding standby letters of credit, i.e. URCG, URDG, UCP, UN Convention on Independent Guarantees and Standby Letters of Credit, ISP etc..

• 한국통신학회논문지
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• 제21권8호
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• pp.1989-2002
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• 1996

In this paper, we describe several warm standby fault-tolerant models and their operation methods applicable to telephone switching control systems which have dual module structure and need high availability. Unavailabilities of the system implemented by four different methods for each model are computed by using the Markov state model, and then are compared for system performance evaluation. As the results ofsimulations, the warm standby model with triple processors is best in the aspect of data loss, while in most cases the warm standby model with doble processors based on no standby check method provides the highest system avaiability. Periodic changeover increases the system unavailability, but the preriodic standby check on standby module decreases the system unavailability of warm standby model with a single processor and with double processors. On the other hands, the variationas of warm standby model with a single processor and with double processors. On the other hand, the variations of data recovery time and personnel recovery rate have little effect on the system unavailtability.

• 대한전기학회논문지:전력기술부문A
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• 제53권8호
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• pp.472-476
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• 2004

Standby power is the electricity consumed in an electrical equipment when it is switched-off or not performing its main function. Due to the acceleration of digital electronics and home networking, standby power use tends to increase rapidly year by year. In this paper, standby power consumption in residential sector in Korea has been surveyed and reported for the first time. Totally 825 pieces of electrical equipments that consume standby power in 53 households were investigated. The average standby power per equipment and total standby power per household were 3.66W and 57.0W, respectively. Annual standby power consumption per household was estimated 306kWh; which means the standby power consumption in residential sector in Korea can be estimated 4.6TWh a year representing 1.67 percent of total electrical consumption (274TWh).

• 산업경영시스템학회지
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• 제40권3호
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• pp.138-147
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• 2017

As the functions and structure of the system are complicated and elaborated, various types of structures are emerging to increase reliability in order to cope with a system requiring higher reliability. Among these, standby systems with standby components for each major component are mainly used in aircraft or power plants requiring high reliability. In this study, we consider a standby system with a multi-functional standby component in which one standby component simultaneously performs the functions of several major components. The structure of a parallel system with multifunctional standby components can also be seen in real aircraft hydraulic pump systems and is very efficient in terms of weight, space, and cost as compared to a basic standby system. All components of the system have complete operation, complete failure, only two states, and the system has multiple states depending on the state of the component. At this time, the multi-functional standby component is assumed to be in a non-operating standby state (Cold Standby) when the main component fails. In addition, the failure rate of each part follows the Weibull distribution which can be expressed as increasing type, constant type, and decreasing type according to the shape parameter. If the Weibull distribution is used, it can be applied to various environments in a realistic manner compared to the exponential distribution that can be reflected only when the failure rate is constant. In this paper, Markov chain analysis method is applied to evaluate the reliability of multi-functional multi-state standby system. In order to verify the validity of the reliability, a graph was generated by applying arbitrary shape parameters and scale parameter values through Excel. In order to analyze the effect of multi-functional multi-state standby system using Weibull distribution, we compared the reliability based on the most basic parallel system and the standby system.

• 한국멀티미디어학회논문지
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• 제17권7호
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• pp.879-885
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• 2014

This paper designs and implements the 2 plug type standby power control outlet based on IEEE 802.15.4 using Zigbee and IPv6 network in order to reduce the standby power to the user. The standby power control system is consisted of direct power and standby power plug. Also this system can communicate bidirectionally in wireless because built-in wireless communication modules. One gateway is linked with many standby power control outlet in wireless. Each standby power control outlet executes the operation needed in power control independently. Also each standby power control outlet has its own power can be detected in real time independently of the power can be controlled.

• 무역상무연구
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• 제20권
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• pp.295-315
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• 2003

Since the end of World War II, the standby letters of credit have been used as a surety device, serving as a performance bond and guarantee in the world. UCP has been used a governing rule for standby letters of credit transactions in international commercial transactions. But the UCP may be sufficient for certain simple standbys, it is not fully applicable nor appropriate for standbys - as is recognized in UCP 500 Article 1. On the other hand, the International Standby Practices(ISP98) provide rules of practice drafted specifically for standby letters of credit intended as an alternative to UCP 500. It became effective on January 1, 1999. In addition to restating general rules applicable to all independent undertakings with greater precision than does UCP 500, thereby reducing the possibility of litigation, it addresses issues that commonly arise in standby practice not addressed in UCP 500. UCP 500 is valid and still applies to standby letter of credit "to the extent to which they may be applicable." Since ISP98 and UCP 500 coexist and may be applicable to standby letters of credit by incorporation, applicants, beneficiaries and issuers have a choice. This study will assist all interested parties in establishing the right rules for the right product, for the right standby letters of credit.

• 전기학회논문지
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• 제56권9호
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• pp.1589-1595
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• 2007

This paper suggests the advanced reliability assessment tool for railway signaling Hot-Standby sparing system. Existing reliability assessment for Hot-Standby sparing system controller is done by using single module mean failure rate based on approximated Hot standby sparing system function. Although approximated Hot standby sparing system function can be applied to various Hot standby sparing system, however, it is not able to reflect the exact system structure. In this paper, we suggest the advanced reliability function by identifying changeover-related failure factors and common failure mode which is not considered in existing approximated Hot standby sparing system reliability function via developing Hot standby sparing system model for railway signaling and applying FMECA to this model. Also. we compare reliability assessment results for model system to reliability assessment for existing system.

• 조명전기설비학회논문지
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• 제26권8호
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• pp.18-26
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• 2012

Recently, there have been suggestions that power factor should be considered to increase the efficiency of electric power supply when evaluating the performance of the electric appliances in standby mode and the related studies have been conducted to improve the efficiency standard of standby power. But, they lack the analysis of the standby power characteristics with the changes of power factor. This study is conducted to analyze the standby power characteristics of TV which is a typical home appliance and reaches a conclusion that the apparent power can be a more reasonable index which reflects the efficiency of electric power supply. It is also found that LED TVs show the best performance in standby mode. Moreover, an example to set standby power standards on TVs to be applied in the future is suggested, considering the energy efficiency policies for appliances.