라즈베리파이를 이용한 IEEE 802.15.4와 IEC 61850 간의 브리지

황성호,Hwang, Sung-Ho 한국인터넷방송통신학회 2017 한국인터넷방송통신학회 논문지 Vol.17 No.5

IEC 61850은 전력 설비 자동화를 위한 표준안이다. 이더넷을 사용하는 IEC 61850을 사용하면, 소규모 배전 변전소인 경우 그 가치보다 자동화하는데 더 많은 비용이 소요될 수 있다. 따라서 소규모 배전 변전소 자동화에는 적은 비용과 간편한 설치가 요구된다. 본 논문에서는 저렴하고 설치가 간편한 IEEE 802.15.4를 사용하고, 기존의 IEC 61850 장비와 연결하기 위해 라즈베리파이를 이용한 IEC 61850과 IEEE 802.15.4간의 브리지를 구현하였다. IEEE 1588을 사용하여, SV, GOOSE와 MMS 같은 IEC 61850 트래픽 성능 평가를 수행하였다. IEC 61850 요구 사항과 성능 평가 결과를 분석하여, IEEE 802.15.4의 적용 범위를 결정하였다. IEC 61850 is a standard for power utility automation. Using IEC 61850 that uses ethernet may consume more costs for the automation than its value in small distribution substations. Thus, less expense and installation cost are required for the automation of small distribution substations. This study used inexpensive and easy-to-install IEEE 802.15.4 and implemented a bridge between IEC 61850 and IEEE 802.15.4, using Raspberry Pi to connect the existing IEC 61850. Using IEEE 1588, IEC 61850 traffic performances were evaluated, such as SV, GOOSE and MMS. Analyzing IEC 61850 requirements and performance evaluation results, the scope of application of IEEE 802.15.4 was decided.

수중 센서 네트워크에서 노드 그룹화를 통한 전송전력 절약 방안

황성호,조호신,Hwang, Sung-Ho,Cho, Ho-Shin 한국음향학회 2009 韓國音響學會誌 Vol.28 No.8

본 논문은 수중 센서 네트워크에서 송수신 노드간 거리가 증가함에 따라 통신을 위한 전송전력이 급격하게 증가하는 단점을 효과적으로 극복하여 보다 낮은 전송 전력으로 통신할 수 있도록 하기 위한 방안을 제안한다. 제안한 방식은 각 노드들을 싱크노드로부터의 거리에 따라 몇 개의 그룹으로 나누고, 해당 그룹에 지정된 대역을 활용하게 한다. 즉, 멀리 떨어져 있어 주파수 증가에 따른 감쇠가 큰 노드들은 저주파수를, 가까운 거리에 있어 주파수 증가에 따른 감쇠가 적은 노드들은 고주파수를 활용하여 전체 노드가 일정 수준 이상의 신호 대 잡음비를 유지함으로써 전송전력을 줄일 수 있게 된다. 각 센서노드들의 거리에 따른 주파수 별 신호 감쇠 특징을 활용하여 그룹의 크기에 따라 가변되는 전송전력을 최소화하는 최적 그룹의 크기를 찾고 그룹의 크기에 비례하여 그룹 별 대역을 할당하는 알고리즘을 제안한다. 제안한 방식은 기존의 그룹을 나누지 않는 방식에 비해 10 dB이상 감소된 전송 전력을 보였다. This paper proposes a transmitted power saving method for underwater acoustic sensors considering the acoustic wave propagation characteristic that propagation loss increases more rapidly in higher frequency band. In the proposed scheme, sensor nodes are divided into a few groups based on the distance between sink node and the sensor node, and each group uses its own frequency band. The node group with longer distance uses lower frequency and the node group with shorter distance uses higher frequency. By means of such a distance-dependent frequency allocation, all sensor nodes are able to maintain a certain target signal-to-noise ratio (SNR), but also save transmitted power. In addition, the optimum size of node group is obtained, and also a frequency allocation algorithm is proposed accordingly. Numerical results show that the proposed scheme saves transmitted power by more 10 dB comparing non-grouping methods.

기계공학에서의 PBL적용 교과과정 개발: 제품해체 설계추론

황성호,권오채,김용세,Hwang Sung-Ho,Kwon Oh-Chae,Kim Yong-Se 한국공학교육학회 2005 공학교육연구 Vol.8 No.1

최근 들어 '학습자 중심의 자기주도 학습' 이라는 새로운 교육패러다임에 대한 관심이 집중되면서, 문제중심학습(Problem-Based Learning; PBL)이 학생의 과학적 사고능력 및 지식의 확장, 적용력, 비판적 지식창출 능력, 창의적 문제해결 능력을 향상시킬 수 있는 방법으로 주목받고 있다. 기계공학 분야에서도 이러한 PBL교육기법을 적용한 교과과정 개발에 대한 노력들이 활발히 전개되고 있으며, 본 논문에서 제시하는 '제품해체 설계추론'교과목도 그러한 교육방법을 적용한 한 예시라 할 수 있다. 제품해체 설계추론은 제품개발에 있어서 그 기여도가 가장 높은 기초물리학이 실제 제품에 어떻게 응용되고 있는가를 학생들이 직접 참여하여 체험할 수 있게 하는 제품해체 학습법 (product dissection)을 도입하여, 설계추론(design reasoning)에 있어서 기초물리학의 중요성을 인식시키는 한편, 다양한 기초과학에 대한 흥미를 유발할 수 있는 실습위주의 교과목이라 할 수 있다. 이러한 교과목을 통하여 창의적 설계 인력 양성에 큰 역할을 할 수 있을 것으로 기대한다. Recently, a new education paradigm 'Self-directed Learning' has attracted considerable attention. Problem-Based Learning (PBL) has been recognized as methodology to help students expand scientific thinking and knowledge. improve applicability, develope critical knowledge, and creatively solve problems. There have been significant efforts to develope PBL-based courses in mechanical engineering. A new PBL-based, multi-disciplinary course 'Product Dissection and Design Reasoning' has been developed in this paper. The course examines the way in which products and machines work and is intended to show freshman or sophomore level students how fundamental physical principles relate to engineering practice through hands-on dissection experience : thus, the course emphasizes the importance of knowledge of the fundamental physics for design reasoning. The primary role of this course is to develop creative design manpower. This paper describes the philosophy and content of this course and presents results from one year of development.

무선 센서 네트워크에서 IEEE 802.15.4 MAC의 이동성 지원

황성호,Hwang, Sung-Ho 한국정보통신학회 2007 한국정보통신학회논문지 Vol.11 No.11

전통적인 센서 네트워크는 고가의 센서와 케이블로 연결되어 있어, 센싱 데이터를 수집할 때 유연성이 떨어지는 단점을 가지고 있다. WSN은 저가의 장비를 사용하고, 임무를 여러 노드에서 나누어서 수행하기 때문에 다각도에서 세밀한 데이터를 수집할 수 있다. 본 논문에서는 대한석탄공사의 작업현장에서 IEEE802.15.4 MAC을 이용하여, 채탄 작업환경을 그대로 적용한 채탄토폴로지를 구성하였다. 채탄 작업시에 작업 관리자의 이동성 지원을 위한 모델들을 제안하였고, 시뮬레이션을 수행하여 최적의 모델을 선정하였다. 본 논문의 결과는 대한석탄공사와 다른 광업소에서 WSN을 적용할 때 중요 자료로 사용할 수 있을 것이다. The traditional sensor network is composed of the cable and the sensor of high price, when collecting a sensing data, there is a weak point which is not pliability. WSN uses the equipment of low price, it will be able to collect the data which is diverse from various node. In this paper we composed coal mining topology which used IEEE802.15.4 MAC in Korea Coal Corporation site. We proposed models for the mobility support of the work manager from the coal mining, we selected the optimum model through simulation experiments. When applying the WSN in the Korea Coal Corporation and other mines, this result can be used as a basis.

군대 소총사격장에서 군인들의 주야간 소음노출평가

황성호,박재범,Hwang, Sung Ho,Park, Jae Bum 한국환경보건학회 2013 한국환경보건학회지 Vol.39 No.4

Objectives: The purpose of this study was to investigate exposure levels to K2 rifle noise at a military rifle range among soldiers in training, the left and right ears of shooters, and control managers in the day and night times. Methods: For this study, we visited military rifle ranges and measured the noise of a K2 rifle with a sound level meter (3M Quest SoundPro$^{TM}$) at four different locations with values of Peak (dB(A)) and Max (dB(A)). Results: The highest peak value of impulse noise level averaged 150.4 dB(A), ranging from 149.7 to 150.5 dB(A) at the left-ear side. Impulse noise levels in the daytime were also recorded as higher than during the night. This result was significantly different between daytime and nighttime locations, such as soldier training, right ear of shooter, and control manager (P < 0.001). Conclusion: This study confirmed that there is a need for proper management of impulse noise at military rifle ranges.

서울지하철 일부 역사 내 부유 곰팡이 농도 및 환경요인

황성호,안재경,박재범,Hwang, Sung Ho,Ahn, Jae Kyoung,Park, Jae Bum 한국환경보건학회 2014 한국환경보건학회지 Vol.40 No.2

Objectives: We measured the concentrations of culturable airborne fungi (CAF) in enclosed environments at 16 underground subway stations of the Seoul Metro in 2013, and investigated the effect of environmental factors, including temperature, relative humidity, the number of passengers, and distance from the platform. Methods: The cultured fungi were identified by the lactophenol cotton blue (LPCB) staining method and were classified by observing the form, shape, and color of colony. A nonparametric analysis was used to determine if the differences in the concentrations of CAF were statistically significant. Results: The concentrations of CAF at the stations were the highest in station p ($367CFU/m^3$) with arange between 3 and $437CFU/m^3$. There was a significant correlation between CAF concentration and the distance from platform (r = 0.544, p < 0.01). Geotrichum spp. and Penicillium spp. were the predominant species. Conclusion: It is recommended that special attention be given during rush hour, which is in the morning (08:00-10:00) and in the early evening (18:00-19:00) to improve the indoor air quality of the subway stations.

대학스포츠 동아리 참여자의 참여 동기가 운동 지속 및 대학 생활 만족에 미치는 영향

황성호 ( Hwang Sung-ho ),이동희 ( Lee Dong-hee ) 대한체육학회(구 한국유산소운동과학회) 2020 대한스포츠융합학회지 (jcses) Vol.18 No.2

This study investigates the effect of participation motivation of university sports club participants on exercise continuation and university life satisfaction to further revitalize university sports clubs. And further, suggests the ultimate way for university students to expand into lifelong sports through participation in sports clubs in order to lead a pleasant school life. For this study, 253 university students(male 172, female 81) participating in sports clubs at universities located in Gyeonggi-do were selected, and data analysis was performed by using SPSS 20.0 for frequency analysis, Cronbach's alpha reliability analysis, and descriptive analysis. Correlation analysis, t-test and multiple regression analysis were performed. The result is as follows. Firstly, there were significant differences in participation motivation (gender, participation motivation), exercise continuation (gender, participation frequency), and university life satisfaction (participation period, participation time) according to the general characteristics of university sports club participants. Secondly, it was found that participation motivation has a positive (+) effect on exercise continuation. Thirdly, participation motivation was found to have a positive (+) effect on life satisfaction at university. Fourthly, it was seen that exercise continuation has a positive (+) effect on life satisfaction at university. As suggested in this study, participation motivation, exercise continuation, and satisfaction with university life had a significant effect on university sports club participants.

표준대퇴골 모델 종류에 따른 측면 낙상충격 해석

황성호(Sung-Ho Hwang),박지수(Ji Su Park),김태호(Tae-Ho Kim),구상모(Sang-Mo Koo),김충현(Choong Hyun Kim) 한국트라이볼로지학회 2015 한국트라이볼로지학회 학술대회 Vol.2015 No.10

대학실험실과 병원진단검사실에서의 부유진균 농도와 환경영향인자

황성호 ( Sung Ho Hwang ),박동욱 ( Dong Uk Park ),하권철 ( Kwon Chul Ha ),박현희 ( Hyun Hee Park ),주세익 ( Se Ik Joo ),윤충식 ( Chung Sik Yoon ) 한국산업위생학회 2010 한국산업보건학회지 Vol.20 No.4

This study evaluated the airborne concentrations of fungi in university laboratories, hospital diagnostic laboratories in Seoul. The incubated fungi was identified by lactophenol cotton blue(LPCB) staining method. Variables such as types of ventilation, temperature and relative humidity were investigated to explain laboratory airborne fungal concentrations. A total of 97 air samples were collected from 10 facilities in two institutions. Aspergilus spp., including Aspergilus niger, Aspergillius flavos and Penicillium spp. were found as predominant species. Airborne fungal concentrations ranged from not detected (ND) to 1,890 CFU/㎥. Airborne fungal concentrations were high in general-ventilated facilities and in laboratories where relative humidity (>60%) were high (p<0.001). Therefore, we suggest that relative humidity should be maintained to properly reduce the concentration of fungal in university and hospital laboratories.

무선센서네트워크를 이용한 애완동물 위치추적 및 원격모니터링 시스템

황성호(Hwang, Sung-Ho),박재춘(Park, Jae-Choon),권기현(Kwon, Ki-Hyeon),최신형(Choi Shin-Hyeong) 한국산학기술학회 2011 한국산학기술학회논문지 Vol.12 No.1

본 논문에서는 애완동물의 생활 패턴과 습성을 연구하기 위해, 초음파, 온도, 습도와 조도 센서를 이용한 애 완동물 위치추적 및 원격모니터링 시스템을 설계하였다. 애완동물의 위치를 파악하기 위해 초음파를 사용하여 거리 계산을 하였고, WSN(Wireless Sensor Network)을 이용하여 애완동물이 위치하는 장소의 온도, 습도와 조도 같은 센 싱데이터들은 싱크모트로 전송하였다. 애완동물 모니터링 시스템에서는 수신된 센싱데이터들을 실시간으로 데이터베 이스에 저장하고, 실제 공간에서 애완동물의 위치를 파악하였다. 송신모트들 사이의 간섭(interference) 문제는, 싱크모 트의 비콘을 기준으로 송신모트들 간에 순차적으로 전송함으로써 해결하였다. 탐색된 위치를 시간별로 분석하여 애 완동물의 이동패턴과 이동영역, 온도, 습도와 조도 등을 GUI(Graphical User Interface) 형태로 나타내는 애완동물 모 니터링 시스템을 실험실 모델로 구현 및 실험하였다. In this paper, we design a pet location tracking and remote monitoring system that uses ultrasonic, temperature, humidity and illumination sensors to study behavioral patterns and habits. Using ultrasonic waves to calculate distances, a WSN(Wireless Sensor Network) was constructed to transmit data at pet's location, such as temperature, humidity and illumination, to a sink mote. Data received by the system are stored in the database in real time to trace pet's location. Interference among transmitting motes was eliminated by sequentially transmitting RF beacons using sink mote's beacon as the reference signal. Experiments were performed with the laboratory prototype of a pet animal monitoring system implemented for this study. The system analyzes locations of a pet and displays movement patterns, areas of movement, temperature, humidity and illumination using a GUI (graphical user interface).