• 한국지진공학회:학술대회논문집
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• 한국지진공학회 1999년도 춘계 학술발표회 논문집 Proceedings of EESK Conference-Spring
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• pp.85-92
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• 1999

Blasting induced damage boundary was determined by measuring vibrations adjacent to charging holes. the criterion adopted to define damages is that blasting-induced strains exceeding tension-crack strain level cause damages. The blasting vibrations were measured in terms of acceleration and converted to strains. The tension-crack strain level was determined with tensile strengths and elastic moduli of rock cores. The damage zone was found to be extended radially about 1 meter from the blasthole detonated with 250 to 700 grams of explosives. The comparison of shear wave velocity profiles before and after blasting shows that the damage boundary of 1 meter seems to be reliable.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2022년도 학술발표회
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• pp.138-138
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• 2022

Understanding a stream's or river's discharge is essential for a variety of hydrological and geomorphological applications at various sizes. However, depending on the stream environment and flow conditions, it is crucial to use the appropriate techniques and instruments. This will ensure that discharge estimations are as reliable as possible. This study presents developed smart system for continuous measurement of open channel discharge and evaluate streamflow measurement over various techniques. This includes developed smart flow meter as flow point measurements, smart water level sensor (installed on Hydraulic Structure ? Weir) and current meters. Advantages and disadvantages of each equipment are presented to ensure that the most appropriate method can be selected. we found that smart water level sensor is more prominent once used during flood event as compared to smart flow meter and current meters, while current meters seems to show better accuracy once applied for open channel.

• 한국조경학회지
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• 제23권1호
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• pp.123-139
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• 1995

The megalopolis citizens are reevaluating the expectant value and the perception of leisure aceording to increasing the level of their incomes, The leisure of citizens is increasing in the aspect of quantity and quality of life nowadays In the site planning of leisure, the concrete understanding about people's choice of a leisure site will be the most important thing, not only for the aspect of improvement of the quality of life but also efficiencies of the land use The purposes of chi study are firstly, to find out the factors which are influenced on a choice of Outdoor leisure facilities in neighbourhood unit and to Compare the Characteristics Of Choice models between the three metropolitan areas, secondly, to predict a limitation of use areal according to the change of a needed time based on the metropolitan's standard choice model For the choice model establishment this research used Logit Model which has been used in the field of the traffic, the tourism and the economics. This research made the results which find out the influencing variables with needed times, the accessibility and the percentage of facilities. The lindtations of use areas come out the results which are predicted according to the change of needed times as a most influencing factors. The range of each preferred leisure facility is about 956 meter distant in the neighbourhood park about 644 meter distant in the pocket park about 604 meter distant in the recreation center, about 628 meter distant in the tennis court about 974 meter distant in the private hob by facility and about 528 meter distant in the library from the apartment unit The recreation center and the library are nearer facilities than the other facilities. But these facilities are surveyed to be more or less influenced by an interesting progran, a context of events and the level of useful facilities, etc.

• 한국위성정보통신학회논문지
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• 제9권2호
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• pp.38-44
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• 2014

본 논문은 FMCW(Frequency Modulated Continuous Wave) 레이더 레벨 측정기 설계와 시뮬레이션을 통한 성능분석에 대하여 기술한다. 설계된 레벨미터는 FMCW radar를 이용하여 최대 20m 거리를 측정하며, 거리 계산을 위한 비트신호 분석기법으로 FFT(Fast Fourier Transform)와 Zoom-FFT를 적용하였다. 성능 분석을 위해 시뮬레이션을 통하여 두가지 기법을 비교 분석한 결과, 측정오류를 최소화하고 측정의 분해능을 향상시키기 위해서는 Zoom-FFT 기법이 보다 적절한 기법임을 확인하였다. 시뮬레이션은 주파수 분해능과 측정거리 분해능의 최적 값을 얻기 위해 다양한 조건에서 분석하였고, 1.024GHz 주파수 조건에서 2.2mm의 측정 분해능을 확인하였다.

• 한국인터넷방송통신학회논문지
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• 제20권5호
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• pp.51-56
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• 2020

측정 명령어에 따른 정확도와 소요시간은 효율적인 Ka 밴드용 자동 시험 장비(ATE)를 구축하는데 중요한 요소이다. 이에 따라 본 논문에서는 RF 대표 계측기 Power Meter의 측정 명령어에 대해 연구하였다. 30 G ~ 31 GHz에서 Power Meter의 측정 명령어 FETCH와 MEASURE의 각 측정 레벨에 따른 정확도와 소요시간을 비교하였으며, -70 ~ +20 dBm 영역을 2가지 Power Sensor로 측정하였다. 측정 결과 신속하게 데이터를 불러오는 FETCH 명령어는 잡음 레벨보다 높은 선형 구간에서 비교적 정확한 데이터를 얻을 수 있었다. 가장 정확한 데이터를 얻을 수 있는 MEASURE 명령어는 FETCH 대비 시간이 많이 소요 되었으며, 최대 13.2초가 소요 되었다. 이를 통해 30 G ~ 31 GHz에서 Power Meter 측정 명령어의 정확도와 측정 소요시간을 확인할 수 있었고, 해당 연구 결과는 효율적인 Ka 밴드용 ATE를 구축하는데 기준을 제시할 수 있을 것으로 기대된다.

• 문화기술의 융합
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• 제6권4호
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• pp.435-443
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• 2020

이 연구는 블루투스 염도계 사용이 어린이집에서 제공하는 국의 적정 염도 수준을 조절하는 데 영향을 미칠 수 있는지 확인하고자, 2019년 1월부터 12월까지 안양시 어린이급식관리지원센터에 등록된 어린이집 중 나트륨 저감화 특화사업에 참여를 희망하는 어린이집(블루투스 염도계 사용 군, BG)과 참여하지 않은 어린이집(블루투스 염도계 미사용군, NG)을 대상으로 실시하였다. 연구 결과, 블루투스 염도계 사용 여부에 따라 국의 염도와 나트륨양을 비교하였을 때, BG의 값이 NG보다 유의하게 낮았으며, 블루투스 염도계의 사용 횟수가 증가함에 따라 염도와 나트륨양이 감소하였다. 결론적으로, 블루투스 염도계는 어린이집에서의 나트륨 저감화 교육과 관련하여 조리원들의 자발적인 염도 조절을 유도하는 수단으로 활용 가능할 것으로 사료된다.

• 한국컴퓨터정보학회논문지
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• 제19권7호
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• pp.47-57
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• 2014

정보보안 (인터넷 혹은 사이버) 위협 레벨을 공지하기 위해 많은 정보보안 회사들은 위협 계수기(Threat Meter)를 개발하였다. 본 논문에서는 물리보안 장치들이 지능화되고 네트워크를 통해 감시 및 제어가 가능함에 따라 물리보안의 현재 위협 수준을 결정하는 물리보안 위협 계수기(PSTM: Physical Security Threat Meter)를 제안한다. 따라서 PSTM은 정보보안에서 사용하는 위협 계수기와 유사하다. 이러한 목적을 위해 물리보안 이벤트를 분석하고 가중치를 결정하였으며 복수의 보안이벤트 발생에 따른 이벤트 간 시간 연관성 영향을 고려하였다. 또한 위협 레벨을 결정하기 위한 기준 값 설정 방법과 이들 기준 값을 이용한 실용적인 PSTM을 제안하였다. 특히 출입문 제어기와 CCTV(비디오 분석기 포함)로 구성된 실험환경에서 PSTM을 제작하기 위한 구체적인 블록도와 구현과정을 보임으로써 제안된 기법이 실현 가능함을 보였다. 마지막으로 몇몇 실험 시나리오를 대상으로 실시한 시뮬레이션 결과를 통해 제안된 PSTM이 물리보안 위협레벨을 적절히 공지함을 검증하였다.

• 대한임베디드공학회논문지
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• 제15권4호
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• pp.167-175
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• 2020

A blood-glucose meter is one of the in vitro diagnostic devices to measure and control the glucose concentration of diabetics. In order to measure the glucose level in the blood, the common method is to measure the amount of electrons, that is, the output current generated by glucose oxidation after a blood sample is inserted into the test strip containing an enzyme. The hematocrit is an obstacle in measuring accurate blood glucose concentration. This paper deals with the design and implementation of a blood-glucose meter to correct the hematocrit interference. We propose a sequential method which measures impedance using the alternating current and then measures glucose in the blood using the direct current. In addition, this paper introduces how to use commercial glucose strips based on the proposed system. Finally, we conducted the performance evaluation of the proposed system by comparing the measured current and impedance with those of the references. As a result, the standard deviation of the current measurement is approximately 0.6nA and the impedance measurement error for measuring the hematocrit is approximately within 1%. The proposed system will improve the accuracy of the conventional blood-glucose meter by reducing the hematocrit interference.

• 한국의류학회지
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• 제46권5호
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• pp.723-740
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• 2022

This study aimed to develop an Arduino-based garment pressure device (APD) on the basis of using Single-Tact sensor by suggesting the reliable clothing pressure range and coefficient of selected sensors through the APD calibration process. Once the APD was validated, the pressure of the experimental men's lower body compression wears was measured using the APD and was compared to the pressure measured using the existing air-pack type pressure meter. The subjects were one mannequin and eight men in their 20's, and the trial compression wears were calf sleeves and pants. Clothing pressures were measured in hip, mid-thigh, calf, and ankle. In terms of the 99% confidence level, the experimental clothing pressure measured at the designated measuring points using the APD was considered identical to the one measured using an existing clothing pressure meter. Therefore, on the basis of the experiment results, this study demonstrated that the APD is as reliable as the existing clothing pressure meter within the pressure ranges of 0.54-16.79 kPa and 0.18-25.47 kPa as provided by the SingleTact sensor supplier's data on the basis of using an external ADC (Analog to Digital Converter) module.

• Journal of Advanced Marine Engineering and Technology
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• 제25권2호
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• pp.338-344
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• 2001

According to the MARPOL 73/78 of Convention, all ships should have oil filtering equipment and 15 ppm bilge which satisfy Requirements of MARPOL 73/78. This study is concerned with designing and manufacturing a prototype Oil content Meter(OCM) used in machinery area of ship. The prototype OCM is composed of two parts which are oil content sensing module and data processing unit. The oil content sensing module consists of infra-red light source, photo-diode light receivers, and a glass tube for bilge water sample. The data processing unit has a micro-processor as hard core and peripheral devices. The experimental results of prototype OCM and analysis of collected data reveal linear property between transmitted light and scattered light as long as the bilge water has low level content of oil. And this linear property leads to a oil content detecting method which is programmed and loaded into the data processing unit. The performance of the prototype OCM is compared with that of the commercial OCM in the market.