• Proceedings of the Safety Management and Science Conference
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• 2011.11a
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• pp.593-618
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• 2011

Development of the economy and the growing income of people interested in the leisure and health has been focused. Past the town common wells and groundwater around the water, but health is a priority these days to solve the drinking water directly from tap water, but most people work from home, through the water purifier has been resolved. Depending on seasonal changes and personal taste of coffee, if you can enjoy a snack and water purifier is a restaurant, lounge, public areas and focusing on the rapid spread of the fire, water purifier as compared to the total number of fires increased by 0.03% per year trend on, but the washrooms fire and fire-related research data and case studies with analysis of the exact cause lack of proper preventive measures are insufficient reality. In this study, focusing on electrical energy using a water cooler to understand the structure and principles of fire, the fire revealed the mechanism is vulnerable to the consideration of factors, the exact cause of the fire investigation and the Assistant, manufacturing defects, and to contribute to fire prevention review should.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.13 no.1
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• pp.54-62
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• 1988

For code division multiple access, a frequency synthesizer of elementary components is necessary in the system application of frequency hopped spread spectrum communication. This paper proposes the model of N-loop PLL frequency synthesizer to be adaptied for generating the output frequency resultes in the frequency hopping pattern and to be easy in practical application of the system. It was analyzed how the frequency divider ratio distribute, what the method to decide frequency divider ratio is and what relationship of bandwidth of BPF and degree of multiple have is also analyzed in order to hop the desired frequency output.

• Proceedings of the Korea Water Resources Association Conference
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• 2015.05a
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• pp.116-116
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• 2015

국내 수도사업은 국가 경제 성장과 함께 괄목할만하게 발전하여, 2013년 기준 상수도 보급률은 98.5%로 선진국 수준이다. 하지만 국내 물 소비자의 음용형태를 살펴보면 전체 소비자의 절반 이상이 물을 끊여서 음용하며, 정수기를 사용하여 음용하는 경우도 수돗물 이용 가정의 48.9%나 된다(수돗물홍보협회, 2012). 또한 수돗물에 대한 음용률은 매년 감소, 2009년 56%이었던 음용률이 2012년 53.1%까지 하락하였다. 이렇듯 국내 수돗물의 음용수율이 낮아지는 이유는 '막연한 불신'과 함께 '물탱트와 수도관', 그리고 '냄새와 물맛' 등이다. 이에 K-water에서는 고양, 문산 등을 대상으로 "건강한 물 공급을 위한 스마트 워터 시티" 사업을 시범추진하였다. 추진 목적은 취수원에서 수도꼭지까지 수돗물 공급 全 과정에 ICT를 접목, 수량과 수질을 과학적으로 관리하고, 그 결과 "소비자가 신뢰하는 건강한 수돗물"을 제공하는 물의 도시 구현이다. 본 논고에서는 현재 K-water에서 추진하고 있는 "스마트 워터 시티" 사업의 현황 및 기대효과, 나아가 향후 계획을 소개하고자 한다.

• The monthly packaging world
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• s.354
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• pp.106-117
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• 2022

환경부는 지난 5월 3일 '자원의 절약과 재활용촉진에 관한 법률 시행령(약칭 : 자원재활용법 시행령)'을 일부 개정했다. 합성수지재질 제품의 회수와 재활용을 촉진하기 위해 제품·포장재의 제조업자나 수입업자가 제품·포장재의 제조 또는 수입으로 발생한 폐기물을 회수해 재활용해야 하는 재활용의무 대상 제품·포장재에 합성수지재질의 제품 중 산업용 필름, 교체용 정수기 필터, 어망, 폴리프로필렌 재질의 생활용품 등 15개 품목을 추가한 것이다. 다만 사업자의 급격한 부담 증가를 방지하기 위해 전년도 연간 매출액이 10억 원 미만인 제조업자 등은 2025년까지 재활용의무를 면제받을 수 있다. 다음에 그 상세한 내용을 지난호에 이어서 살펴보도록 한다. 재활용의무를 면제받을 수 있다. 다음에 그 상세한 내용을 지난호에 이어서 살펴보도록 한다.

• Journal of Food Hygiene and Safety
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• v.14 no.4
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• pp.433-435
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• 1999

The number of viable microorganism in drinking water was monitored according to storage temperature and storage period. The number of general bacteria in underground water was 10$^2$~10$^{5}$ CFU/ml and that of coliform group was decreased after 7days. The number of general bacteria in bottle water was increased until 7days but decreased after that day. Coliform group in bottle water were detected only 1 sample. The number of general bacteria in purified water was 10$^3$~10$^4$CFU/ml and 10$^2$~10$^4$CFU/m1 at 8$^{\circ}C$ and $25^{\circ}C$, respectively. Coliform group were not detected in purified water.

• Journal of the Institute of Electronics and Information Engineers
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• v.51 no.6
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• pp.290-297
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• 2014

The synchronization of OFDM receiver is consisted of symbol timing offset(STO) estimation in time domain and carrier frequency offset(CFO) estimation in frequency domain. This paper proposes new algorithm for correcting the integer CFO after we have done correcting the STO and partial CFO. ICFO must be corrected, since the ICFO lead to degrade bit error rate(BER) of demodulation performance. The PN sequence has information which is subcarrier order since the modified PN sequence, length is same subcarrier, is used in this paper and is modulated each subcarrier by each chip. Thus the receiver track phase of PN sequence after FFTin order to find the subcarrier frequency offset. The proposed algorithm is faster and more simple than convenient methode as measuring carrier energy.

• Journal of the Korea Organic Resources Recycling Association
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• v.8 no.1
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• pp.103-108
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• 2000

As it is forbidden to landfill the organic sludge generated in water treatment plant from 2001, disposal coast of the sludge will be highly incersed. Therefore, This Study was conducted to recyle the sludge of water supply plant as inorganic fertilizer for agricultural areas and forests using the Chemical and the Hydrothermal methods. As the result, we could manufacture sutiable inorganic fertilizer, removing organics and harmful heavy metals by the Chemical and the Hydrothermal method.

• The Transactions of the Korean Institute of Power Electronics
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• v.15 no.2
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• pp.142-149
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• 2010

Interior Permanent Magnet Synchronous Motor(IPMSM) have gained an increasing popularity in recent years for a variety of industrial applications, because of their high power density, high efficiency and possibility of flux weakening operation. Because the efficiency of IPMSM is one of the important performance characteristic, the Maximum Torque Per Ampere(MTPA) operating method has been indispensible. In theory, MTPA operating point can be calculated using the exact values of the machine parameters. However, the values of the IPMSM parameters are known to vary widely according to the operating condition. Therefore, to operate the IPMSM in the MTPA operating point, the machine parameters should be estimated in real-time. In this paper, the new MTPA operating method based on the signal injection is presented. By injecting the high frequency current signal, the MTPA operating criteria can be calculated by measuring the input power to IPMSM. The proposed method can find the MTPA operating point with simple signal processing regardless of the parameter variation.

• Proceedings of the Korean Information Science Society Conference
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• 2006.06a
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• pp.319-321
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• 2006

본 논문에서는 다양한 캐리 전달 방식(carry propagation scheme)이 단일 가산기 설계를 위하여 복합적으로 사용되는 가산기 구조물 제안하며. 이를 통하여 보다 향상된 delay-area trade-off 점들을 갖는 설계공간을 생성한다. 제안된 구조의 가산기는 각기 다른 캐리전달 방식의 하부 가산기 블록들을 캐리 입/출력 신호를 선형으로 연결한 구조이며, 기존의 단일 캐리전달 방식의 가산기와 달리, 다양한 delay-area trade-off 특성을 갖는 여러 종류의 캐리전달 방식을 비트 수준에서 조합하여 사용함으로써 보다 섬세한 delay-area 설계공간을 생성해낼 수 있다. 그러나, 제안된 가산기 구조의 설계공간은 다양한 캐리전달 방식이 비트 수준에서 할당되므로, 할당가능한 설계 조합은 설계하고자 하는 가산기의 비트 폭과 고려하는 캐리전달 방식의 수에 비례하여 폭발적으로 증가하게 된다. 따라서, 제안된 가산기의 효율적이며, 자동화된 설계공간 탐색 방범이 요구된다. 본 논문에서는 이를 해결하기 위하여 정수 선형 프로그래밍 (Integer Linear Programming, ILP) 방법을 이용하여 제안한 가산기의 최적화 문제를 형식화함으로써 효과적인 설계공간의 탐색 방법을 제안하였다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.12 no.1
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• pp.1-8
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• 1987

In this paper, resonance frequencies of a reentrant cavity are computed by the mode matching method and the mode orthogonality. The reentrant cavity is composed of a coaxial cable and a cylindrical waveguide, so that resonance frequencies of the resonator can be varied by adjusting the length of the inner conductor of a coaxial cable. The result can be applied to numerous microwave devices such as klystron, wavemeter and resonant circuits of a amplifier and to the measurement of dielectric parameters.