• 한국신재생에너지학회:학술대회논문집
• /
• 2008.05a
• /
• pp.642-645
• /
• 2008

A pin fin with variable fin base thickness is analysed by using the one dimensional analytic method. Heat loss and fin thermal resistance are presented as a function of the fin base thickness, pin fin outer radius and convection characteristic numbers ratio. The relationship between the fin outer radius and fin base thickness for the same amount of heat loss is shown. One of the results indicates the fin thermal resistance decreases as the fin outer radius and/or convection characteristic numbers ratio increase whereas the fin thermal resistance is independent on the variation of fin base thickness.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2005.06a
• /
• pp.1788-1792
• /
• 2005

Eddy current sensor is representative instrument measuring gap to base metal and sensing trouble in base metal. The existing eddy current sensor works as measuring variance of sensor coil's inductance. But, sensor coil have phenomenon that not only inductance but also real resistance varies in real action. Conductivity and Permeability are main variable in sensor coil's varying impedance(inductance, real resistance). By searching relationship between conductivity-permeability and sensor coil's impedance, eddy current sensor gain advantage of elevation of accuracy, removal of alignment to each base metal, and continuous sensing to varying base metal.

• Proceedings of the Korean Nuclear Society Conference
• /
• 1995.10a
• /
• pp.173-178
• /
• 1995

The verification phase of knowledge base is an important part for developing reliable expert systems, especially in nuclear industry. Although several strategies or tools have been developed to perform potential ewer checking, they often neglect the reliability of verification methods. Because a Petri net provides a uniform mathematical formalization of knowledge base, it has been employed for knowledge base verification. In this work, we devise and suggest an automated tool, called COKEP (Checker Of Knowledge base using Extended Petri net), for detecting incorrectness, inconsistency, and incompleteness in a knowledge base. The scope of the verification problem is expanded to chained errors, unlike previous studies that assumed error incidence to be limited to rule pairs only. In addition, we consider certainty factor in checking, because most of knowledge bases have certainty factors.

• Journal of the Korean Operations Research and Management Science Society
• /
• v.3 no.2
• /
• pp.47-74
• /
• 1978

This paper reviews the zero-base budgeting whose concept was developed in the late 1960's, and applied to the actual budgeting situations in the early 1970's. Since then, it has been expanded to become one of major tools in corporate planning and control system. The primary purpose of this review is to clarify the followings: 1) concept of zero-base budgeting and its history, 2) relationships among zero-base budgeting, planning and program evaluation, 3) comparison of zero-base budgeting with other budgeting techniques, and 4) implementation procedure. Some discussions are also provided with respect to the practical implications of zero-base budgeting, its advantages and disadvantages, and others. Finally, the possibility of actual application in a local setting is investigated.

• International Journal of Highway Engineering
• /
• v.6 no.2 s.20
• /
• pp.61-70
• /
• 2004

Cement treated Soil has superior characteristics as pavement-base including strength, curability, hardness, freezing resistance. However drying shrinkage of Cement treated base has been indicated as disadvantage, since reflection crack of surface layer is induced from drying shrinkage of cement treated base. This study propriety about low-shrinkage cement treated base that can control shrinkage of cement and control reflection crack at asphalt overlay & concrete slab.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
• /
• 2003.11a
• /
• pp.1351-1355
• /
• 2003

최근 의류용 감성소재가 다양해지면서 소재의 특성에 따른 최적 설계가 data-base에서 빨리 공급 될 수 있다면 시행착오에 따른 시간과 경비가 적게 소비되면서 소비자의 요구에 빨리 대응할 수 있는 소위 Q.R.도 가능하게 될 것이다. 이러한 감성 의류용 직물의 data base화를 위해서는 rapier, water-jet, air-jet 등 직기에 따른 소재의 설계분포 그리고 직기의 종류에 따라서 직물 설계 data의 분포가 어떠한지를 우선 조사하여야 한다. 본 연구에서는 국내 3개 업체의 실제 현장에서 생산되고 있는 PET 소재의 감성의류용 직물소재의 설계 Data를 직기별로 구분하고 직물 설계 조건들을 조사ㆍ분석하여 경사, 위사 번수별 조직계수를 계산하여 이들 data를 data-base화하고 도시하였다. 또한 이들 분석된 그래프에서 직기 종류별, 직물 조직별, 소재 item별 조직계수와 직물밀도를 예측할 수 있는 방법을 제시함과 더불어 조직에 따른 이들 직물의 설계조건을 제안함으로서 실제 현장에서 쉽게 사용할 수 있는 연구자료를 업체에 제공하고자 한다.

• Computers and Concrete
• /
• v.13 no.3
• /
• pp.377-387
• /
• 2014

This paper presents an experimental study on socket base connections of precast reinforced concrete columns. The main purpose of this study is to determine socket base connection which has the closest behavior to monolithic casted column-base joints. For this purpose, six specimens having different column-socket base connection details were tested under cyclic loading. For each test, strength, stiffness, ductility and drift ratios of the specimens were determined. Test results indicated that a suggested connection type is 10%-30% stronger than the other type of connections under lateral loading. The welded connection (PC-5) had better lateral load carrying capacity and ductility. On the other hand, performance of standard connection (PC-1) which is commonly used in construction was weaker than other connections. Thus, decision of connection type should be referred not only performance but also applicability.

• Earthquakes and Structures
• /
• v.19 no.2
• /
• pp.103-117
• /
• 2020

The effect of the foundation size on the efficiency of seismic base isolation using a layer of stone pebbles is experimentally investigated. Four scaled models of buildings with different stiffnesses (from very stiff to soft) were tested, each with the so-called small and large foundation, and exposed to four different accelerograms (different predominant periods and durations). Tests were conducted so that the strains in the model remained elastic and afterwards the models were tested until collapse. Each model was tested for the case of the foundation being supported on a rigid base and on an aseismic layer. Compared to the smaller foundation, the larger foundation results in a reduced rocking effect, higher earthquake forces and lower bearing capacity of the tested models, with respectable efficiency (reduced strain/stress, displacement and increase of the ultimate bearing capacity of the model) for the considered seismic base isolation compared to the foundation on a rigid base.

• Structural Engineering and Mechanics
• /
• v.39 no.3
• /
• pp.399-410
• /
• 2011

Base isolation, having quite simple contents, aims to protect the buildings from earthquake-induced damages by installing structural components having low horizontal stiffness between substructure and superstructure. In this study, an appropriate base isolation system for 2-D reinforced concrete frame is investigated. For different structural heights, the structural systems of 2, 3 and 4 bays are modeled by applying base isolation systems and results are compared with conventional structural systems. 1999 Marmara earthquake data is used for applying the model by time history method in SAP2000 package. Results of various parameters such as base shear force, structure drift ratio, structure period and superstructure acceleration are discussed for all models.

• Korean Journal of Mathematics
• /
• v.10 no.1
• /
• pp.5-10
• /
• 2002

In this paper, we investigate the prefilter base on a fuzzy set and fuzzy net ${\varphi}$ on the fuzzy topological space (X,${\delta}$). And we show that the prefilter base $\mathcal{B}({\varphi})$ determines by the fuzzy net ${\varphi}$ converge to a fuzzy point $p$ iff the fuzzy net ${\varphi}$ converge to a fuzzy point $p$. Also we prove that if the prefilter base $\mathcal{B}$ converge to a fuzzy point $p$, then the $\mathcal{B}$ has the cluster point $p$.