• 한국화재소방학회:학술대회논문집
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• 한국화재소방학회 1997년도 International Symposium on Fire Science and Technology
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• pp.19-26
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• 1997

Firesafety design engineerings have been mainly derived from complicated rearrangement of descriptive specifications in codes or regulations through a great number of lessons from fire disasters. In this paper, the author refers to some recent developments in the field of building fire protection. At first, the author expresses his viewpoints concerning performance-based design codes, which have been popular throughout the world as a symbol of freedom from restricted usage of building materials and components prescrived in regulation or bylaws, in spite of some conflicts between objects-oriented design method and industrial mass production. Secondly, the author introduces several innovative fire protection methods adopted for large or void spaces in building complex. Finally, the author forcasts a next development of firesafety science and technology, aimed at securing personal safety in hyperscale urban areas.

• Journal of Biosystems Engineering
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• 제10권1호
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• pp.13-23
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• 1985

Spraying method from the paddy-field levee is known to give insufficient penetration of the spray droplets to the rice stem of the densely grown plants, which is generally encountered at the last stage of rice growth. This study was intended to investigate the spraying system to solve this existing problem. As an approach, it was attempted to develop the boom-with-nozzle, between-the-row application system. Several types of nozzles and their different arrangements in the boom were tested in the field to measure the penetration-reaching distance and the uniformity of spray droplet distribution. The results of the study are summarized as follows: 1. Field experiments by the spraying method from the paddy-field levee showed to have practically no penetration of the spray droplets to the portion of the plant stem with the normal flow volume generally applied and thus need for improving present spraying method. 2. It was found that, considering both the uniformity of the spray droplet distribution and performance rate, the most efficient type of nozzle in the between-the-row boom-type spraying system was one that has core-insert hollow-cone with some clearance between the cone and tip. 3. When tested by applying the spraying method of between-the-row, the nozzle pressure did not affect the uniformity of spray droplet distribution. However, the nozzle pressure had a positive effect on the penetrating-reaching distance of the facing side of the rice stem and did not affect much on that of the opposite face of the stem. It was also found that the maximum pressure to affect the penetration-reaching distance was about $10kg/cm^2$. 4. The uniformity of the spray droplet distribution in the between-the-row system was greatly affected by the height and orientation of the nozzles in the boom. Based on experimental work for the different type of the boom-with-nozzle arrangements, it is recommended that the position of nozzle is set at about 0.45 m above the ground and two nozzles in the boom are oriented to be faced with each other with some angle such that the droplet stream from the nozzle would not directly face with each other.

• Journal of Power Electronics
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• 제13권5호
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• pp.806-813
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• 2013

This paper aims to compare the performance of three phase induction motor drives using Five Leg Inverter (FLI) and Three Leg Inverter (TLI) configurations. An Indirect Field Oriented Control (IFOC) method using a TLI is well established and incorporated for high performance speed drives in various industries. The FLI dual motor drive system on the other hand shows good workability in the independent control of two induction motor drives simultaneously. In this experiment, the IFOC method is utilized for both drive systems, and Space Vector Pulse Width Modulation (SVPWM) is used to generate pulses for both inverters. For the FLI, the Double Zero Sequence (DZS) Injection technique is used to generate the modulation signal. The complete experiment setup is done by using a DSpace 1103 controller board. The individual motor performances are analyzed using similar schemes, equipment setups and controller parameter values. The results show similar speed performance response capability between the single motor operation using a TLI system and the two motor operation using a FLI system based on the variable speed range either in forward or reverse operation. They also show similar load rejection abilities. However, the single motor with a TLI has a better power quality aspect such as ripple current and total harmonics distortion (THD).

• 제어로봇시스템학회논문지
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• 제20권1호
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• pp.78-86
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• 2014

This paper proposes a method of tracking an object for a person-following mobile robot by combining a monocular camera and a laser scanner, where each sensor can supplement the weaknesses of the other sensor. For human-robot interaction, a mobile robot needs to maintain a distance between a moving person and itself. Maintaining distance consists of two parts: object tracking and person-following. Object tracking consists of particle filtering and online learning using shape features which are extracted from an image. A monocular camera easily fails to track a person due to a narrow field-of-view and influence of illumination changes, and has therefore been used together with a laser scanner. After constructing the geometric relation between the differently oriented sensors, the proposed method demonstrates its robustness in tracking and following a person with a success rate of 94.7% in indoor environments with varying lighting conditions and even when a moving object is located between the robot and the person.

• 국제학술발표논문집
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• The 6th International Conference on Construction Engineering and Project Management
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• pp.195-199
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• 2015

Many conventional management methods have emphasized the minimization of required resources along the supply chain. Accordingly, this paper presents a proposed method called the Virtual Design and Construction (VDC)-aided system. It is based on object-oriented resource control, in order to accomplish a feed-forward control monitoring supply chain logistics. The system is supported by two main parts: (1) IT-based Technologies; and (2) VDC Models. They enable the system to convey proactive information from the detection technology to its linked visualization. The paper includes a field study as the system's pre-test: the Scaffolding Works in a LNG Mega Project. The study demonstrates a system of real-time productivity monitoring by use of the RFIDbased Mobile Information Hub. The on-line 'productivity dashboard' provides an opportunity to display the continuing processes for each work-package. This research project offers the observed opportunities created by the developed system. Future work will entail research experiments aimed towards system validation.

• Journal of Power Electronics
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• 제17권1호
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• pp.136-148
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• 2017

In recent years, voltage source multilevel converters are very popular in medium/high-voltage industrial applications, among which the NPC/H-Bridge converter is a popular solution to the medium/high-voltage drive systems. The conventional finite control set model predictive control (FCS-MPC) strategy is not practical for multilevel converters due to their substantial calculation requirements, especially under high number of voltage levels. To solve this problem, a hierarchical model predictive voltage control (HMPVC) strategy with referring to the implementation of g-h coordinate space vector modulation (SVM) is proposed. By the hierarchical structure of different cost functions, load currents can be controlled well and common mode voltage can be maintained at low values. The proposed strategy could be easily expanded to the systems with high number of voltage levels while the amount of required calculation is significantly reduced and the advantages of the conventional FCS-MPC strategy are reserved. In addition, a HMPVC-based field oriented control scheme is applied to a drive system with the NPC/H-Bridge converter. Both steady-state and transient performances are evaluated by simulations and experiments with a down-scaled NPC/H-Bridge converter prototype under various conditions, which validate the proposed HMPVC strategy.

• Journal of Preventive Medicine and Public Health
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• 제13권1호
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• pp.53-66
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• 1980

The editorials of the leading newspapers may reflect as well as help formulate the public opinions to a significant degree. Bearing this in mind, this study was carried out to provide information useful in formulating such public health policies that could practically meet the social interests and demands in health appearing in the editorials of the newspapers. This analysis covered the editorials of 5 leading newspapers such as Donga Ilbo, Chungang Ilbo, Hankook Ilto, Chosun Ilbo and Seoul Shinmoon for about 10 years from Jan. 1st, 1970 through Oct. 31th, 1979. The major findings are as follows: 1. The total number of health-concerned editorials in the five daily papers for the period was 1,768 or occupied 6.4% of the total editorials of the same sources. The increasing trend of frequnecy of the health-concerned editorials since 1976 indicates the increment of social interests and demands in health. Analysing the contents, environmental pollution received the greatest attention in those editorials, which was followed by medical affairs, environmental sanitation, and disease control in order in terms of frequency of appearance. However, there was a tendency that the interests in the environmental pollution, medical affairs and social welfare tended to increase year by year, whereas those in environmental hygiene and disease control comparatively decreased. 2. Motives of dealing with the health-concerned editorials were provided by announcement of the governmental policies and implementation for 25.6% and by out-breaks of the relevant events for 23.9%. This tendency coincides with the general characteristics of the editorials that reflect the timely issues. Closely analysing, however, the fact that the motives engendered by the out-breaks of the relevant events or by the season concerned comparatively tended to decrease as years pass by, indicates that the editorials tend more to seek the future-oriented demands in health rather than the current issue-oriented. 3. The editorials appeared to be more concerned with the governmental policies. 95.7% of all the editorials analysed were addressed to the government. This signifies the role of government in the field of public health and medical affairs. Their attitudes toward health-related policies of the government were much more negative than the other editorials that were addressed to the government in other fields. This suggests that the governmental interests in health were neither sufficient nor fair. 4. What the editorials most stressed were; (1) increment of governmental interests in health, (2) improvement of the governmental health administration, (3) enriching the basic statistics, and (4) development of various technologies pertinent to health affairs and disease control, and so forth. However, must of their suggestions were not concrete but rather abstract and conceptual. 5. The editorials also expressed strong interests in research area. The areas of the needed research most suggested by items are; (1) development of effective health care delivery system, (2) establishment of more practical system of calculating medical cost, (3) implementation of effective policies to control degenerative diseases, (4) division of medical care services and pharmaceutical services systems, (5) effective ways to prevent Co poisoning accidents, (6) changing status of environmental pollution and its effects upon health, and (7) status of occupational diseases, and so forth. 6. There were some editorials -not small in quantity -that have risk to mislead the public opinions as well as the health policies due to lack of professional knowledge of the writers. It is desirable to establish some kind of mechanism that screens the erroneous contents of the editorials to help prevent misleading opinions.

• 정보교육학회논문지
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• 제23권5호
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• pp.441-449
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• 2019

2015 개정 교육과정이 도입됨에 따라 초등학교에서도 소프트웨어 교육이 의무화되었다. 실과 교과의 한 단원으로 구성되는 소프트웨어 교육의 내용은, 정보 윤리, 알고리즘과 프로그래밍, 컴퓨터과학의 원리로 이루어져 있는데 교수 학습 방법으로 놀이 중심의 언플러그드 활동을 권장하고 있다. 하지만 현장 교사들은 적합한 언플러그드 활동 자료의 부재를 가장 큰 어려움으로 생각하고 있었으며, 기존 자료가 성취기준 달성에 적합하지 않다는 점, 단순한 놀이 교육이 많아 컴퓨팅 활동과 연계되지 않는 점 등을 해결해야 할 문제로 지적하였다. 이에 본 연구에서는 초등 소프트웨어 교육의 성취기준으로 제시된 기본 제어구조는 물론 센서를 활용한 다양한 활동을 통해 창의적 문제해결력을 키울 수 있는 언플러그드 활동 중심의 로봇을 개발하였고 이를 활용한 소프트웨어 수업을 통해 효과성을 검증하였다.

• 재활치료과학
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• 제10권2호
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• pp.53-74
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• 2021

목적 : 본 연구는 아동을 대상으로 하는 운동기능 평가 및 중재방법에 대한 국외 문헌들을 중심으로 분석하고자 하였다. 연구방법 : 본 연구는 2010년 1월부터 2020년 3월까지의 국외 학술지에 게재된 문헌을 PubMed, Cochrane library(Embase)를 통하여 검색하였으며, 주요 검색용어는 motor function test, motor function measure, movement assessment, motor proficiency test, motor scale, motor skill, children을 사용하여 검색하였다. 결과 : 총 37편의 연구 중 14편의 평가, 23편의 중재로 분석되었으며, 중재에 관한 연구 디자인은 모두 RCT design이었다. 운동기능 중재보다 평가 연구가 증가하는 추세를 보였다. 연구분야는 재활분야에서 가장 빈번하였으며, 평가에 관한 연구는 AIMS와 MABC-II, 중재에서는 GMFM이 가장 많이 사용되었다. 중재 종류는 Task-oriented training(6편)이 가장 많이 사용되었다. 결론 : 본 연구는 국외에서 실시된 아동의 운동기능 중재와 평가에 관련된 연구를 분석함으로써 국내 치료사들이 임상에서 효과적인 운동기능 평가와 중재를 선택할 수 있도록 근거를 제공하고자 하였다.

• 디지털콘텐츠학회 논문지
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• 제3권2호
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• pp.245-254
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• 2002

현재, 자동화 시스템을 위한 통신분야는 TCP/IP를 기반으로 하는 네트워크 기반 원격제어 부분과 시스템의 각 내부 장치들간의 통신을 위한 간단한 직렬통신으로 나뉠 수 있다. 네트워크의 비약적인 발전에도 불구하고 내부 제어를 위한 통신부분은 현재까지 간단한 RS232기반을 사용하고 있다. 또한, 시스템의 개발기법은 각 기능단위의 모듈러 프로그래밍 기법에서 객체지향 프로그램으로 발전하였으며, 현재는 소프트웨어의 부품단위인 컴포넌트 기반 개발기법으로 발전하였다. 이는, 비즈니스 로직을 포함하는 독립적인 운영단위를 조립하며 새로운 시스템의 개발로 이어지는 기법으로서 소프트웨어 개발기법의 새로운 대안으로 제시되고 있다. 따라서, 본 연구는 컴포넌트 기반의 개발 기법을 적용한 GUI기반의 RS232C에서의 내부통신 Emulate를 구현하였다. 이는, 수신부와 송신부로 나뉘어지는 통신 제어부분을 컴포넌트화 하였으며, 이를 합성함으로서 제어부에서는 송,수신 데이터의 핸들링을 담당하도록 하였다.