Microstrainer 설계를 위한 개량여과 이론

김병조,Qasim,Syed R,Verma,Rameshwar D 한국화학공학회 1971 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.9 No.3

The use of microstrainers in the water and wastewater engineering field is expected to increase in the future. Currently employed design methods for microstrainers are based on Boucher's straining law which assumes a constant rate of flow. The assumption of a constant pressure head is more appropriate than that of a constant flow rate. Governing equations describing the hydraulics of filtration through microstrainers based on these two assumptions are analyzed and compared.

새로운 안보개념(安保槪念)에 따른 국민안보의식(國民安保意識) 분석(分析)

김병조 국방대학교 안보문제연구소 1994 국방연구 Vol.37 No.2

Coacervation-상분리법으로 만든 Ethyl Cellulose 마이크로캅셀의 Glibenclamide 방출특성 및 수용성 첨가제의 영향

김병조,장정수,이문주,김상헌,최영욱 중앙대학교 약학연구소 1996 약학 논총 Vol.10 No.-

Glibenclamide (GBC) is a well-known antidiabetic agent, which stimulates the secretion of endogenous insulin by pancreatic βcells. However, administration of GBC at a high dose can occasionally induced the fatal hypoglycemia, especially in the patients with impaired liver function. Therefore, in order to develop an oral sustained-release preparation which reduces the side effect, microcapsulation of GBC has been carried out in this experiment. Microcapsules of GBC were prepared by coacervation-phase separation method with ethylcellulose as a wall-forming material in cyclohexane, using polyisobutylene as a coacervation-inducing agent. Different amounts of hydrophilic additives. L-arginine(ARG) and polyethylene glycol 4000 (PEG), were added to the microcapsule wall, in order to alter the porosity of the wall and hence to enhance the release of the core material. The microcapsules prepared were examined for physical properties by scanning electron microscopy (SEM) and particle size analysis. The release of the poorly water-soluble GBC was found to be very slow from the microcapsules and strongly dependent on the core to wall ratio of the microcapsules, but it was accelerated considerably with increasing amount of PEG or ARG. In general, on the basis of dissolution kinetics, GBC releases from microcapsules were followed apparent first-order kinetics, while the dissolution data of GBC powder conformed to Hixon-Crowell's cube root law. Therefore, in conclusion, it might be possible to design the sustained-release formulation by the combination of both GBC powder and microcapsules of different core wall ratio with or without hydrophilic additives.

풍향에 따른 풍압적분법의 유효성 검증에 관한 연구

김병조,하영철 한국풍공학회 2012 한국풍공학회지 Vol.16 No.4

It is difficult to evaluate wind load of irregular shaped buildings and tall buildings by using multiple degrees of freedom. Because, in general wind loads of those were estimated based on the first mode of vibration. These problems can be solved by using the Pressure Integral Method (PIM). The PIM is a method to estimate wind force of floors and it can be able to analyze wind load of irregular buildings and multiple degrees of freedom. However, If analysis of multiple degrees of freedom has been done by using PIM, there is no way to directly test the validity of a PIM. In prior studies to validate the PIM analysis for a wind direction, the linear mode was adopted as the vibration mode of the building. The results of the PIM analysis were then compared to existing wind tunnel tests (High Frequency Force Balance, and the Aeroelastic Model Test). As the results of these studies, it shows that the linear responses using PIM and the other methods were similar. However, the validation of PIM in according to variation of wind directions has not been investigated. Thus, this study is to verify the validity of PIM for wind directions. The results of PIM were compared to those of High Frequency Force Balance test. 현행의 비정형 건축물과 고층 건축물의 풍하중 평가방법은 건축물의 진동모드로 선형모드를 사용하고, 1자유도 해석을 수행하기 때문에 고차모드 및 다자유도 해석에는 한계가 있다. 이러한 한계를 극복하기 위해 개발된 방법은 풍압적분법이다. 풍압적분법은 층별 풍력을 산출하는 방법으로 비정형 및 다자유도 해석을 가능하게 한다. 하지만 풍압적분법에 의해 다자유도 해석을 수행할 경우 그 유효성을 직접적으로 검증할 수 있는 방법이 없다. 따라서 선행연구에서는 풍압적분법의 유효성을 검증하기 위해 건축물의 진동모드로 선형모드를 선택하여 하나의 풍향에 대한 풍압적분법과 기존의 풍동실험방법(풍력실험, 공력진동실험)에 의해 산출된 풍응답을 비교하였고, 그 결과 각 실험에 의한 풍응답이 모두 유사하게 나타났다. 선행연구결과는 하나의 풍향에 대한 결과이므로, 본 연구에서는 풍압적분법의 적용성을 높이기 위해 풍향변화에 따른 풍압적분법의 유효성 검증연구를 수행하였다. 그 검증대상은 풍력실험에 의해 산출된 풍응답과 비교하였다.

Wearable device를 이용한 선원의 수면 시간과 효율성에 관한 기초연구

김병조,이정훈,이수경,권해연 한국항해항만학회 2018 한국항해항만학회 학술대회논문집 Vol.2018 No.추계

선원은 충분한 수면으로 신체적 정신적 피로를 완전히 회복하지 못한 수면부족 상태에서 재승선하여 장기간 항해와 흔들리는 선박 위에서 반복적인 작업 활동을 수행하므로 누적 피로도와 스트레스가 증가하는 악순환을 초래하며 이로 인한 해양 인적사고가 발생할 수있다. 따라서 사람의 주관적인 판단에 의한 자기평가방법으로 기입하는 설문지 분석이 아닌 선박에 승선하는 동안에 Wearable device를 착용한 상태에서 과학적이고 객관적인 선원의 수면 시간과 효율성을 분석하였다.

공업계 고등학교 학생들의 진로 및 직업교육의 문제점과 개선방안에 대한 연구

김병조,최병정,장준호 경기대학교 교육대학원 2008 경기교육논총 Vol.- No.17

Relational Assets, Interorganizational Mechanisms, and Alliance Performance of Venture Firms in Korea

김병조,조동성 한국전략경영학회 2009 전략경영연구 Vol.12 No.1

The field of interfirm cooperation in strategic management literature has been considered as the essential topic. Scholars, however, have argued that it is not fully understood what factors drive the superior alliance performance. Up to date, hundreds of researches have tried to reveal the performance drivers in various cooperative settings, using a diverse theoretical lens. Recently, many researchers are struggling for dealing with the process issues in alliance research, using the ‘dynamic view’ on firm’s strategic behavior. These endeavors are stem from the reflection on the bulk of researches represented by the ‘static’ views and/or ‘content-based’ researches on cooperative behavior. Based on the capability-based view, this paper examines the performance drivers of an alliances formed by 137 Korean technology-intensive ventures. The result, first, shows that the relation-specific investment in relational assets such as alliance function, manual, and training would be beneficial to a firm entering into cooperative relationships. Second, the result shows that the investment in and establishment of the interorganizational mechanisms for selecting partners, coordinating relational activities, and mutual learning also would be advantageous to the higher alliance performance.

선원의 누적 피로도와 스트레스에 영향을 미치는 요인분석에 관한 연구

김병조,이정훈,이수경,권해연 해양환경안전학회 2018 해양환경안전학회 학술발표대회 논문집 Vol.2018 No.06

Moyamoya병 1례

김병조,김성환,박용원,이기재 인제대학교 1993 仁濟醫學 Vol.14 No.4

저자들은 뇌혈관조영술로 확진된 Moyamoya병 1례를 경험하였기에 문헌고찰과 함께 보고하는 바이다. Moyamoya disease is a chronic, progressive vascular disorder, characterized by stenosis or occlusion of the supraclinoid portion of the internal carotid artery with extension Into the proximal portion of the anterior and middle cerebral arteries. There is an associated finding of collateral vascular networks(Moyamoya vessels, that is "something hazy, like a puff of smoke" appearance) in the region of the basal ganglia. We experienced a case of Moyamoya disease in a 11 year old girl who had frequent episodic transient weakness of the left lower extremity and headache, which was confirmed by four vessel angiogram.

전기화재 예방을 위한 배선용 차단기의 응동 특성에 관한 연구

김병조,김재호 大田大學校 産業技術硏究所 2014 산업기술연구소 論文集 Vol.25 No.1

The Molded Case Circuit Breaker (MCCB) is widely used for low voltage class electrical circuit prevention from the over and fault currents caused by over load and utility fault conditions, respectively. In the electrical circuit there is a certain possibility that a fault can occur, and it could cause electrical fire at electrical devices and cables. The over and fault currents are tripped by MCCB that disconnect the electrical equipments. In this study, the operational characteristics of MCCB was analyzed when the over current flow as well as the current ramping up rates for electrical fire prevention. The trip time was decreased according to increasing current and ramping up rates. Also the operational characteristics of the MCCB was shown the inversed definite time curve. 배선용 차단기는 과부하 및 계통 고장 등의 원인에 의해 발생되는 과전류 및 고장전류로부터 저전압 전기회로의 보호를 위해 다양하게 사용되고 있다. 전기회로에서는 고장이 발생하며, 이는 전기기기와 케이블에 화재를 야기 할 수 있다. 과전류 및 고장전류는 배선용 차단기에 의해서 차단되어 지며, 전기기기와 분리되어 진다. 본 연구에서는 전기화재 예방을 위해 과전류 및 전류증가율에 따른 배선용 차단기의 응동 특성을 분석하였다. 차단시간은 과전류 및 전류 증가율이 증가함에 따라 감소하였으며, 또한 배선용 차단기의 응동 특성은 반한시·정한시 곡선을 나타내었다.