전기저항식 로드셀을 이용한 균등긴장시스템 개발 및 성능실험

박원태(Park Weon-Tae),천경식(Chun, Kyoung-Sik) 한국산학기술학회 2016 한국산학기술학회논문지 Vol.17 No.2

MS(Multi-Strand) 케이블은 여러 개의 강연선으로 이루어져있어, 케이블 시공시 각 강연선을 차례대로 개별적으로 긴장한다. 그리고 마지막 강연선이 정착되었을 때, 모든 강연선에 동일한 장력이 도입되어야하며, 이것이 MS 균등긴장의 핵심기술이다. 본 연구에서는 엑스트라도즈(Extradosed)교 및 사장교의 사재케이블(Stay Cable)에 적용되는 2,200MPa 초고강 도 강연선들을 균등하게 긴장, 제어할 수 있는 MS 케이블 균등긴장시스템을 개발하였다. 개발한 균등긴장시스템은 전기저항 식 로드셀, 유압잭, 유압펌프 그리고 통합제어기로 구성되며, Master 강연선과 Slave 강연선의 장력변화를 실시간으로 예측하 며 제어하는 알고리즘을 탑재하였다. 개발시스템의 기능과 성능을 검증하기 위해 균등긴장 실험을 수행한 후, 광양 태인2교 (ED교)의 사재케이블 가설긴장에 성공적으로 적용하였다. Because MS(Multi-Strand) cables consist of many strands, a jacking force is applied to each strand one by one for cable construction. All strands should have an equal tensile force when the last one is wedged. This is the core technology for MS iso-tensioning. In this study, a new MS cable iso-tensioning system was developed for controlling and jacking the high-strength strands, with an ultimate tensile strength of 2,200MPa, for a stay cable of extra-dosed/cable-stayed bridges. The newly developed iso-tensioning system consists of electrical resistance load cells, hydraulic jacking devices, hydraulic pumps, and integrated controllers. Moreover, it is embedded with an algorithm that can control and predict the variations in tensile forces of the Master and Slave strands in real time. Actual experiments were carried out to verify the function and performance of the newly developed system. This system was applied successfully to the stay cable construction of 2nd Tae-in extra-dosed bridge in Gwangyang.

시뮬레이션을 이용한 광주광역시 지하철 운영계획에 관한 연구

전태웅,박수희,이항진 조선대학교 환경공해연구소 1999 環境公害硏究 Vol.15 No.2

This study is concerned with the operation planning in Kwang-ju subway. The operation planning in subway that one is electronic car operating interval time, one other is the number of trailer car. The evaluation criteha of alternatives is average queue time of passenger and the degree of congestion in the trailer car. The alternatives of operating planning and the experiment of alternatives is presented in this paper by simulation with ARENA. The results of experiments, electronic car operating interval time is 3.5 minutes and the number of trailer car is four in 2004 year.

안성지역 대기중 미세입자에 포함된 음이온의 농도분포 특성

천만영,김태욱 안성산업대학교 1996 論文集 Vol.28 No.-

NO_3 and SO^2-_4 concentrations and distributions of airborne fine particles less than 2㎛ in Ansung atmosphere were determined from November 21 to December 2, 1996. The sampling was carried out using 8-stage Hering's low pressure impactor (LPI, aerodynamic cutoff diameters are 0.05, 0.075, 0.11, 0.26, 0.05, 1,0, 2,0 and 40㎛) at the top of a four storied building located at Ansung national university in Ansung. The average concentrations of NO_3 and SO^2-_4 were 9.0, and 84(㎍/㎥) respectively. The distributions of NO_3 concentrations were bimodal types which showed two peaks in the range of 0.075~0.12㎛ and 0.5~1.0㎛ in aerodynamic diameter. And the distributions of SO^-2_4 concentrations were bimodal types which showed two peaks in the range of 0.12~0.26㎛ and 0.5~1.0㎛.

동일하지 않는 병렬기계 시스템에서 지연작업수를 최소화하는 Tabu Search 방법

전태웅,강맹규 한국경영과학회 1995 經營 科學 Vol.12 No.3

This paper presents a Tabu Search method to minimize a number of tardy jobs in the nonidentical parallel machine scheduling. The Tabu Search method employs a restricted neighborhood for the reduction of computation time. In this paper, we use two different types of method for a single machine scheduling. One is Moore's algorithm and the other is insertion method. We discuss computational experiments on more than 1000 test problems.

農業所得 決定要因 分析 : 康津郡의 營農實態를 中心으로 Focused on the Farming Presentation in Kang-Jin County,Chollanamdo

全太甲,張東燮,金映秀 全南大學校 農漁村開發硏究所 1976 農業科學技術硏究 Vol.11 No.-

Its characteristics of Korean agriculture are small scale of arable land, intensive cultivates of ice paddy and barley crop, and family labour agriculture, etc. Korean farmers who inherited agricultural production system and production methods from their ancester's are working on their farm lands without knowledge how much income they made and with the thought that is ought to do. But now is the time when they must count their income whether they have earned the money by farming or not and improve their agricultural system into a scientific farm management from their ancester's simple farming. A good farmer must/can compare his farm management with others and analyze his earning from his farming through a concrete and scientific data, but till now there was almost no one to do that in Korea. This study is focused on the analysis of the co-relation between the agricultural income and its factors affecting to the agricultural income. I classified and intrepreted the farm achievement by gross agricultural income, agricultural income, and farm operating cost and also its factors are as follows; farm management system, farm management intensity, farmers capital condition, efficiency of arable land and labour, and farm capital. According to this results the farm achievement at every management scale and every farm region relies on not only its natural surroundings or farm management conditions but also their using of such conditions. I can say that there are some difference in agricultural income level of each farm management scale and can assure that the most effective farm management level at this research is the middle scale farms, ones who have 1~2 chung bo arable land. Small farmers can cultivate the land per acre most effectively, but it cannot be a economic arable land use because of its small scale. Large farmers introduce the low level of the efficiency of cultivating land capital and intensity, so there are possibilities that can hob' up their farm incomes. I hop this data can be use as a actual proof of real farmers by the other farmers, government officers and relative researchers.

마이크로제어기를 사용한 아크 용접기의 제어 시스템 구현

전태원,김무경 울산대학교 2001 공학연구논문집 Vol.32 No.1

본 논문은 아날로그회로의 오차를 제거하면서 부품 수를 줄이기 위하여 싸이리스터 제어형 아크용접기의 제어시스템을 디지털화 하는 방법을 제시하였다. EPLD로 3상 컨버터의 싸이리스터 게이트 발생회로를 구현하였으며, 실험을 통하여 본 논문에서 제시한 방법의 타당성을 확인하였다. This paper proposes the digitalization method for control system in thyristor controlled arc welding machine in order to delete offsets in analog circuit and reduce the number of devices. The algorithm to generate gating pulses of thyristor at 3-phase controlled rectifier with EPLD is suggested, and the proposed method is verifier with experimental results.

데치는 시간에 따른 침투성 및 비침투성 농약 처리 엽채류의 비타민 및 무기질의 함량 변화

전혜경,안태현,홍정진 한국조리과학회 2005 한국식품조리과학회지 Vol.21 No.1

The present study was conducted to investigate effect of blanching time on changes in vitamin and mineral contents in leafy vegetables treated by different pesticides. Vitamin A content of fresh leafy vegetables was high whorled mallow > chard > spinach hi order and vitamin C content of those was high spinach > whorled mallow > chard in order. Vitamin A and C contents of leafy vegetables treated by non-systemic pesticide were higher than those of leafy vegetables treated by systemic pesticide. Changes in vitamin A and C contents of leafy vegetables treated by systemic pesticide and non-systemic pesticide showed a similar trend. Vitamin A content significantly increased, while vitamin C content significantly decreased by conventional blanching. Changes in mineral contents in leafy vegetables treated by systemic pesticide and non-systemic pesticide showed a similar tread. Upon conventional blanching, Mg in spinach, Mg and Ca in chard and whorled mallow slightly increased, while K in all leafy vegetables remarkably decreased, and Se in spinach slightly decreased and Se in other vegetables remarkably decreased. On the other hand, Na, P, Fe, Cu and Zn in all leafy vegetables slightly decreased or did not show any change.

회전자 저항제어에 의한 권선형 유도전동기 구동 시스템의 소프트 제동

전태원,최명규 울산대학교 1999 공학연구논문집 Vol.30 No.1

회전자 저항제어에 의한 권선형 유도전동기 구동 시스템은 정밀한 속도 또는 위치제어가 필요 없는 응용분야에 적합하다. 본 논문은 이 구동 시스템에서 외부 회전자 저항제어와 함께 발전제동과 직류제동 방식을 적용하여 기계적인 충격 없이 제동되는 기법을 제시하였다. Matlab의 simulink로 시뮬레이션을 수행하여, 이 소프트 제동기법에 대한 타당성을 확인한다. The rotor resistance controlled wound-rotor induction motor drive system is suitable for applications not requiring precise speed and position regulation. In this paper, the soft braking method without mechanical shock is proposed using both the dynamic braking and the dc braking with a external rotor resistance control. The braking method is verified with the simulation results using a MATLAB/SIMULINK.

유도가열용 전류형 인버터의 콘덴서 초기 충전회로 설계

전태원,최명규 울산대학교 1997 공학연구논문집 Vol.28 No.2

유도가열용 병렬공진형 전류형인버터의 싸이리스터를 역방향 걸어주기 위하여 초기 콘덴서전압이 반드시 필요하다. 본 연구에서는 유도가열용 전류형인버터의 초기 콘덴서전압의 충전 장치를 설계하고자 한다. 접합변압기 및 전달선을 포함한 전체 유도가열 부하를 등가 저항 및 인덕턴스 값으로 표시하고, 병렬공진형 전류형인버터에 적당한 초기 충전장치를 구성한다. 시뮬레이션을 통하여 유도가열 부하에 대한 가장 적합한 초기 충전장치의 인덕터 및 커페시터 값을 구한다. The parallel resonant current source inverter for the induction heating requires the initial capacitor voltage in order to apply the reverse voltage to thyristor. This paper presents the design of the initial capacitor charge circuit in the current source inverter for the induction heating. The overall induction heating load including the matching transformer and transmission line is represented by the equivalent resistance and inductance, and then the charge system is constructed, which is proper circuit for the parallel resonant current source inverter. Through simulation results, the best values of indictor and capacitor in the charge system are derived with the impedance of induction heating load.

朝鮮後期 가체와 후계에 관한 硏究 : 北學者 文集을 中心으로 with a Collection of Pukhakja's Works as the Central Focus

전혜숙,김태영 東亞大學校 附設 生活科學硏究所 2002 생활과학연구 논문집 Vol.10 No.-

Pukhak in as the concept indicating the new study tendency which became a prominent figure in the later Chosun period, while going through Imjin, Byungja war, social and economic order was broken down, and Jujahak showed its limit. With the repulsion of this social status, Pukhak was formed from the influence of western study and practical science in Chung period, and it means learning the civilization of the north, also comprehends the significant meaning that the people living in undeveloped culture go and learn developed culture. The society of the later Chosun period is as the most dynamic era which showed the whole change in the society at large with radical change in the inside and outside of the country, and this social character was well reflected in the change of hairstyle. So, ga-che, as the biggest and the most huge hairstyle which can not be found in any other period, became popular. This study has the purpose to criticize the prohibition against ga-che, and its side-effect in society of the latter Chosun period which indicated in collection of Pukhakja, and also to analyze the society of the later Chosun period, by analyzing the views on its hairstyle. In the 18th century when Pukhakpa took an active part in that society, the development of currency economy·growth of commercial capital·merchants or the merchandised public's entry into the society which were accomplished in the process of overcoming the social and economic problems in that era were exerting influence on not only economy but also the society at large. Regarding this, the result of considering the comprehensive significance on the view of the criticism against ga-che in fashion and its extravagant phenomenon and prohibition of ga-che, as well as the assertion of hu -gae, chokduri and hwagwan as the substitute for ga-che which could not but appear as one of social phenomenon in the dynamic change of social and economic structure caused by pukhak movement in the later chosun period is as follows. First, even though pukhakja took an initiative on pukhak movement by asserting the acceptance of pukhak so as to overcome the limitation of chosun-sinocentrism, nevertheless, what they contended prohibition of ga-che on the ground that it was originated from the customs of barbarians, not chinese rules, seems resulted from the influence of chosun-sinocentrism, we can see the ideological conflict and contradictory aspects of pukhakja in this period. Second, from the viewpoint that pukhakja prohibited ga-che as the symbol of extravagance, instead, recommended hu-gae which the political authority selected to be operated in the public, we can see the diligent and frugal as well as practical aspects of pukhak ideology, at the same time, from the viewpoint that chokduri and hwagwan as the substitute for ga-che were used only on necessary occasion, we can also see the practical use and frugality which pukhak pursued.