• 한국지열·수열에너지학회논문집
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• 제14권1호
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• pp.16-21
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• 2018

This work aims to develop a platform to investigate the effect of operation schedules on the building energy consumption and to derive a simulation model based optimal start and stop daily strategy. An open-source building energy simulation tool DOE2 is used for the engine, and the developed simulation model is validated using ASHRAE guideline 14. The effect of late-start/early-stop operation of HVAC system on the daily building energy consumption was analyzed using the developed simulation model. It was found that about 10% of energy consumption cut was possible using the control strategy for an hour of advance of the stop operation, and about 3% per an hour of delay of the start operation.

• 한국통신학회논문지
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• 제21권5호
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• pp.1345-1359
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• 1996

This paper presents a floating point arithmetic unit (FPAU) for supescalar microprocessor that executes fifteen operations such as addition, subtraction, data format converting, and compare operation using two pipelined arithmetic paths and new rounding and normalization scheme. By using two pipelined arithmetic paths, each aritchmetic operation can be assigned into appropriate arithmetic path which high speed operation is possible. The proposed normalization an rouding scheme enables the FPAU to execute roundig operation in parallel with normalization and to reduce timing delay of post-normalization. And by predicting leading one position of results using input operands, leading one detection(LOD) operation to normalize results in the conventional arithmetic unit can be eliminated. Because the FPAU can execuate fifteen single-precision or double-precision floating-point arithmetic operations through three-stage pipelined datapath and support IEEE standard 754, it has appropriate structure which can be ingegrated into superscalar microprocessor.

• 한국지역사회생활과학회지
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• 제26권4호
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• pp.683-696
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• 2015

This study measures patients' meal satisfaction according to the type of operation (self-operation and contract operation) and identifies improvement areas. A survey was conducted using 183 contract operation patients and 60 self-operation patients receiving general meals. The mean score for satisfaction for the whole sample was 3.42 (self-operation = 3.51; contract operation = 3.39), and self-operation satisfaction was significantly higher than contract operation satisfaction. Mean scores were 2.98 for food, 3.26 for menu composition, 3.57 for sanitation, 3.78 for distribution meal services, and 3.50 for menu information. Self-operation showed a higher satisfaction level than the contract operation in food and menu composition. The ccontract operation showed a higher level of satisfaction than self-operation in sanitation, distribution meal services, and menu information. In terms of feeling dissatisfaction with meal services, both groups showed the highest dissatisfaction with food and menus, and both groups agreed on food and menus that required the greatest improvement. Based on the results, contract operation managers should develop and apply menus considering their preferences. Dietitians of self-operation strengthen communication between meal service staff and patients by carrying out periodic and systematic service education on self-operation.

• 대한인간공학회지
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• 제36권1호
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• pp.9-21
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• 2017

Objective: The objective of this study is to understand the effect of angle and curvature of push-return switches, which are external factors in the operation environment inside the cars, on the feel of operation and to propose optimum alternatives. Background: Customers' needs for products are changing from functional and performance aspects to customer-led type where customers can reflect on their needs on the products. The operation inside cars is executed by HMI. The push-return switch is utilized as the most intuitive mode of HMI; therefore, this push-return switch, which is widely used, has to be developed by assessing the preference and satisfaction of the customer. Method: The angle and curvatures, which are external factors that affect the feel of operation, are drawn through surveying the preceding research literatures. The stages to construct alternatives in experiments are as follows: (1) the tactile switch is replaced after dismantling the switch assembly to evaluate the internal characteristics proposed by preceding researches, (2) a drawing is prepared by using a design software, is printed using 3D printer, and then it is attached on the switch assembly, and (3) evaluation for satisfaction of operation is carried out by using a driving simulator. Results: Both the angle and curvature that are external factors of switch significantly affect the feel of operation. However, interaction between the two factors is found insignificant. Therefore, an optimum alternative is proposed considering the experimental outcomes. Conclusion: This study evaluates the satisfaction in operation that affects the feel of operation environment inside the cars. Based on the study results, a guideline for switch design in the center fascia is proposed. Application: This study is expected to be used as basic data for designing automotive switches, as well as switches in the industries similar with the operation environments of cars.

• 조명전기설비학회논문지
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• 제18권5호
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• pp.174-182
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• 2004

높은 생산성, 시스템 설계의 단순화 및 미래 확장에 대비한 여분의 전원 확보 등의 병렬운전 방법의 장점으로 인해 대전력 전원장치에 있어 컨버터 시스템의 병렬운전에 대한 요구가 점점 증가되어 왔다. DC-DC 컨버터의 소신호 모델을 토대로 하여, 병렬운전 시스템의 모델을 제안하였으며 각 컨버터 모듈간의 균일한 전류분배를 위해 제안된 균등 전류 분배법을 사용한 병렬운전 시스템에 대하여 논의하였다. 모의실험 프로그램을 사용하여, 서로 특성이 다른 컨버터 모듈로 구성된 병렬운전 시스템에서 마스터와 슬레이브 모듈의 위치가 자동적으로 변하면서 전류분배 오차는 제한 값 이내로 유지됨을 확인하였다. 병렬운전을 위한 제안된 컨버터 시스템의 운전 특성을 확인하기 위하여 1[kW]의 DC-DC 컨버터 모듈 2대를 제작 실험하였으며 모의실험 결과는 과도특성 및 기동특성에 있어 실험 결과와 잘 일치됨을 확인하였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 합동 추계학술대회 논문집 정보 및 제어부문
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• pp.268-273
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• 2002

In this paper, a new parallel multiplier circuit over $GF(2^m)$ has been proposed. The new multiplier is composed of polynomial multiplicative operation part and modular arithmetic operation part, irreducible polynomial operation part. And each operation has modular circuit block. For design the new proposed circuit, it develop generalized equations using frame each operation idea and show a example for $GF(2^m)$.

• Journal of Biosystems Engineering
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• 제23권1호
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• pp.75-82
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• 1998

Autonomous speedsprayer operation was conducted using a fuzzy controller combined with a DGPS. The signal of DGPS receiver and signals of four ultrasonic sensors were processed in real time. The speedsprayer was steered with two levers controlled by two hydraulic cylinders. The fuzzy controller has two inputs; direction of running obtained from the DGPS receiver and distance from trees measured by ultrasonic sensors. The operation times of the hydraulic cylinders were inferred as outputs of the fuzzy controller. Field test results showed that the speedsprayer could be autonomously operated by the developed fuzzy controller including turning operation in the end of the tree row. The ultrasonic sensors contributed a little to performance of the autonomous operation, but the speedsprayer could avoid trees or obstacles in emergent situations with them.

• Journal of Computational Design and Engineering
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• 제1권4호
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• pp.233-242
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• 2014

A magnetically levitated vehicle (Maglev) system is under commercialization as a new transportation system in Korea. The Maglev is operated by an unmanned automatic control system. Therefore, the plan of train operation should be carefully established and validated in advance. In general, when making a train operation plan, statistically predicted traffic data is used. However, a traffic wave often occurs in real train service, and demand-driven simulation technology is required to review a train operation plan and service quality considering traffic waves. We propose a method and model to simulate Maglev operation considering continuous demand changes. For this purpose, we employed a discrete event model that is suitable for modeling the behavior of railway passenger transportation. We modeled the system hierarchically using discrete event system specification (DEVS) formalism. In addition, through implementation and an experiment using the DEVSim++ simulation environment, we tested the feasibility of the proposed model. Our experimental results also verified that our demand-driven simulation technology can be used for a priori review of train operation plans and strategies.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2012년도 춘계 학술논문 발표대회
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• pp.341-343
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• 2012

This study introduces a method for computation of process and operation gap in the specific construction operation(i.e., RC frame construction applying a block-grouping scheme) using CYCLONE-based simulation modeling and analysis technique. Since uncertainty of construction environment exists, a thoughtful production planning is required to effectively deal with a risk resulting in schedule delay in advance. This study presents the concepts of a time delay occurred in a process level and operation level in a operation model, and a method of measuring gap-times in each level while the simulation progresses. It helps a site manager to decide how many segmentation in a construction block is suitable for eliminating unproductive time-delays under the constrained resources (e.g., laborer, equipment). A case study presents a network model representing a three segmented RC frame work, and result obtained from the simulation experiment.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2003년도 추계학술대회 논문집(III)
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• pp.145-150
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• 2003

The national subway went under construction in 1971, and after three years of endeavor, Seoul subway line number one opened for traffic in 1974. Line number two went under construction in 1978 and it opened for traffic in 1984. With the use of safety operation for more than 20 years, the life cycle nearly came to an end. Therefore the improvements for the safety operation are unavoidable. The total system should not be affected when the new and conventional systems are overlapped, the system operation is in the initial stage, and it confronts the situation of abnormal operation. However, there is a total lack of experience in construction and improvement for the trains that are in the use of large transport and density headway. In this paper, we propose an improvement method of the subway signalling system using ATO (Automatic Train Operation control scheme) to which the latest Digital ATC is applied, and examine the first application model of ATO system.