우선 순위를 이용한 셀룰러 이동국의 전송률 제어

정창규 한국교통대학교 2019 한국교통대학교 논문집 Vol.54 No.-

This paper propose the control method of throughputs for each mobile stations without changed total average throughputs. This method apply different priority parameter to each mobile station in cell. Normally the proportional fairness and priority of each mobile station is different according to channel circumstance and system for each mobile station in cell in order to maximize a average throughput. But, This scheduler make lower priority mobile station always have lower throughput. Therefore control of the priority of each mobile staion is needed to maintain the total throughput in system. Assuming the priority of one mobile station is lower 50% than the other mobile station, simulation results show that total throughput of a cell with a priority controlling of each mobiles is equal to total throughput without controlling.

CDMA2000 이동국의 단일톤 간섭억제와 수신기 차단 특성 분석

정창규 忠州大學校 2003 한국교통대학교 논문집 Vol.38 No.3

This paper shows that noise figure and selectivity of RF part depend on system parameters such as single tone desensitization and receiver blocking. Noise figure of system is choosed by 8dB that is recommanded by Qualcomm. Simulation proved that In case of spreading rate of SR1 and code rate of 1/3, attenuation are -73.2dB and -62.2dB respectively when interference powers are -30dBm and -40dBm, and In receiver blocking characteristic, if noise figure of mobile station is 8dB, spreading rate is SR1, and jamming power is -102dBm, attenuations at point seperated by ±5000KHz from center frequency are -46dB and -46.8dB while code rate are 1/3 and 1/2, respectively.

평면 MIMO 시스템의 수직 배열 안테나 채널 특성

정창규 韓國交通大學校 2013 한국교통대학교 논문집 Vol.48 No.-

In this paper, vertical wireless channel characteristics of planar MIMO system is analyzed by using 3D ray-tracing simulator, Wireless Insite in microcell environments. The analysis shows that increasing the height of transmit antennas results in the higher angular spread and direction of departure. On the other hand, increasing the distance between transmit antennas to receive antennas results in the smaller angular spread and direction of departure.

하향링크 조절을 위한 비례공정 계획 알고리듬의 일반화

정창규 한국교통대학교 2017 한국교통대학교 논문집 Vol.52 No.-

This paper propose the scheduling algorithm for a down link of cellular system that controls the fairness and link capacity between users using a fairness factor and user's weights. The adopted system model assume that each mobile station calculate a maximum rate of a down link and feedback it to base station. The scheduler of a base station decide the mobile station in service for next time slot according to a schedule algorithm based on feedback rate information. The generalized procedure is proved that induce a scheduling algorithm from a any utility function. The utility function is generated by parameter  which control a proportional fairness and user's priority, respectively. Finally, The proposed method obtains generalized proportional fairness scheduling algorithm.

협력 SDMA와 빔 성형기술의 주파수 효율성 분석

정창규 忠州大學校 2010 한국교통대학교 논문집 Vol.45 No.-

This paper propose a collaborative SDMA and collaborative beamforming technique suppressing adjacent cell interferences effectively induced by adjacent BTS, using partial channel information transferred by AT through a restricted feedback channel at reverse link in FDD collaborative wireless communication systems. Simulation shows that Channel capacity of collaborative-SDMA is superior to that of noncollaborative-SDMA.

제한된 부호행렬을 사용한 이동국 선택 기법

정창규 한국교통대학교 2020 한국교통대학교 논문집 Vol.55 No.-

This paper propose the method of providing high data rate to mobile in a service area using a restricted code matrix in a time division duplex system. Normally conventional methods dicide the channel circumstance of each mobile station at a base station. This method calculate the signal to interference plus noise ratio of a forward channel at each mobile station and each mobile station send he signal to interference plus noise ratio, the index of a restricted precode matrix and selected coulmn vector. the conventional method maximize signal power of mobile station in spite of not knowing the interference with adjacent mobile station. But a proposed method achieve high performance because of knowing the interference with adjacent mobile station. Simulation results show that the throughput of system increase with a highly correlated antena and increasing the number of mobile station makes a throughput increasing slightly. Also a highly correlated system provide 1.17 times higher throughput than a loosely correlated system.

Prevalence and Clinical Characteristics of Local Allergic Rhinitis to House Dust Mites

정창규,신유섭,이지호,반가영,박해심 연세대학교의과대학 2017 Yonsei medical journal Vol.58 No.5

Local allergic rhinitis (LAR) is a localized nasal allergic response in the absence of systemic atopy. The aim of this study was to evaluate the prevalence and clinical characteristics of LAR in Korean rhinitis patients compared to allergic rhinitis (AR) and non-allergic rhinitis (NAR). A total of 304 rhinitis patients were enrolled from November 2014 to March 2016. A skin prick test, serum total and specific immunoglobulin E, and a nasal provocation test (NPT) with house dust mite (HDM) were performed on all patients. Subjects also documented changes in rhinitis symptoms before and after NPT. Seventy-four patients with nasal hyper-reactivityand 80 patients with subclinical allergy were excluded. AR was diagnosed in 69 (46.0%) patients, NAR in 75 (50.0%) patients,and LAR to HDM in 6 (4.0%) patients. The average medication score and disease duration of each group were 14.5 points and 77.6 months in AR, 12.1 point and 51.1 months in NAR, and 17.7 point and 106.0 months in LAR, respectively. There were no significant differences in the baseline nasal symptom score of the three groups. However, after NPT with HDM, the score of rhinitis,itching, and obstructive were 4.83±1.47 vs. 1.95±2.53, 3.00±2.10 vs. 1.45±2.06, and 5.50±1.38 vs. 2.57±2.84 in LAR and NAR, respectively(p<0.05). LAR patients had longer duration of disease and tended to be older and have higher medication score than other rhinitis patients.

환경에 따른 MIMO 모드 선택 알고리듬

정창규 한국교통대학교 2016 한국교통대학교 논문집 Vol.51 No.-

This paper analyze the performance of Multi-Input Mult-Output Technologies according to the velocity, geometry, spatial correlation and number of a moblile station in a same cell. In case of each mobile station's being active, Initial MIMO mode selection algorithm is proposed that provides maximum channel capacity in each channel circumstance. And a modified algorithm also show that each mobile station whose initial MIMO mode is selective mode choose either space division multiple access technology or spatial multiplexing technology owing to the number of that mobile station.

이동 WiMAX 시스템 레벨 시뮬레이터 구현

정창규 忠州大學校 2012 한국교통대학교 논문집 Vol.47 No.-

In this paper the system level simulator(SLS) of a Mobile Wimax system is realized. A SLS analyze a lot of performance of MIMO(Multiple-Input Multiple Output) mode 0, MIMO mode 1, MIMO mode 2, MIMO mode 4 in lots of circumstance. Simulation results show that capacity of mode 4 is more reduced than mode 2 according to a reduced number of feedback CQI(Channel Quality Indicator).

지속가능발전교육 관점에 입각한 웹기반 기후변화 환경교육이 초등학생의 환경 인식 및 태도에 미치는 영향

정창규,이상원 이화여자대학교 사범대학 교과교육연구소 2010 교과교육학연구 Vol.14 No.3

본 연구는 웹기반을 활용한 기후변화 환경교육이 초등학생의 환경 인식과 태도에 어떠한 영향을 미치는지 알아보고자 하였다. 이를 위해 선행연구 고찰을 통하여 웹기반을 활용한 기후변화교육에 관한 교수·학습 모형 및 프로그램을 개발하고, 학습 현장에 적용하였다. 그 효과를 검증하기 위한 검사지는 황수정(2009)이 개발한 설문지를 재구성하였으며, 연구과정에서 얻어진 정량적 자료는 SPSS 12.0 프로그램을 이용하여 분석하고, 정량적 분석의 한계를 보완하기 위하여 정성적 분석을 실시하였다. 본 연구의 결과는 첫째, 지속가능발전 관점에서 바라본 기후변화에 관련된 내용을 추출 및 재구성하여 웹기반을 활용한 기후변화 환경교육을 위한 교수·학습 모형을 개발하고, 이를 바탕으로 환경교육 프로그램을 구안 및 적용시켰다. 둘째, 웹기반을 활용한 기후변화 환경교육 프로그램이 초등학생의 환경 인식 및 태도에 긍정적 영향을 미쳤다. 셋째, 웹기반을 활용한 기후변화 환경교육 프로그램의 적용은 지식적 측면에서는 차이를 보이진 않았다. 넷째, 웹기반을 활용한 기후변화 환경교육 프로그램을 적용한 후에 환경 인식이 높은 학생일수록 환경태도가 높게 나타났다. 결론적으로 웹기반을 활용한 기후변화 환경교육 프로그램은 초등학교 학교현장에 적용 가능하며, 다양한 환경교육 방법이 요구되고 있는 시점에서 새로운 교육방법으로써 그 가치가 크다고 할 수 있다. 차후 이와 관련된 심층적인 연구와 교수ㆍ학습 활동에 관한 후속 연구가 필요하다고 본다. The purpose of this study was to investigate the influence of the web-based climate change educational program on environmental awareness and attitudes of 5th grade elementary school students in Gyeonggi-Do. The students were divided into an experiment group and a control group. A reconstructed questionnaire through Hwang(2009)`s test tool was used to survey the affects of web-based climate change educational programs. The SPSS 12.0 program was used to analyze the results. The major results of this study were as follows: First, the researcher was able to develop and apply a professor-learning model for web-based climate change environmental education by extracting and recreating the climate change-related contents from 5th and 6th grader curriculum. Second, the web-based climate change educational program had a positive effect on elementary school students’ environmental awareness and attitude. Third, after implementing the web-based climate change educational program, the students with higher environmental awareness showed a higher regard for the environment. In conclusion, the web-based climate change educational program was effectively used on elementary school students and the program proved to have a positive affect on 5th graders’ environmental awareness and attitude. Therefore, in-depth study and follow-up research on teaching and learning activities should be highly considered.