• Journal of The Korean Society of Agricultural Engineers
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• v.58 no.4
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• pp.1-8
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• 2016

In 2008, 17, 596 dams and reservoirs are scattered across South Korea, and 17, 505 of them (99.5 %) are used for agriculture and 99.3 % are fill dam types. This study aimed to review literature related to the precise safety diagnosis system for agricultural reservoirs established by Korea Rural Community Corporation (KRCC) and analyze problems of its evaluation method. And then, it proposed ways to improve the system including a modified diagnosis system, which was applied to pilot districts in order to verify the utility. For assessment model development of agricultural reservoir, we reviewed status of precision safety inspections systems of agricultural reservoir. There are many problems such as assess agricultural reservoir not by sheet which used in fill dam but by block which used in concrete dam construction and diversion tunnel which main element in reservoir levee is treated as water intake facility. For considering diversion tunnel in reservoir levee, previous precision safety inspection systems which summed in separated phenomenon, separated element, separated site, separated facility was change to new systems which summed in site, phenomenon, element, and facility. Compared results of previous inspection system calculated total assessment index (Ec) with new system calculated total assessment index (Ec) are not show statistical difference.

• Journal of the Architectural Institute of Korea Planning & Design
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• v.35 no.7
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• pp.45-52
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• 2019

In recent years, there has been a demand for a residential supply model that can actively and flexibly cope with various housing demands in the changing paradigm of public rental housing. This study focuses on the two-step supply system that has been studied in Japan. It was used to examine and analyze cases to recommend a supply plan that can be used for domestic public rental housing. In more detail, the literature review of the two-step supply system discloses that four types by supply methods (A-1, A-2, B-2, and C-2) and four types of relationship (construction and management combine entities type, management entity type, construction entity type, a separated entity type) can be categorized. In addition, from the actual case study, it revealed that the way of linking and supplying activities among the entity can have a great influence on "ease of supply (supply)", "diversity of housing demand (diversity)," and "quality of construction (construction)". "Ease of supply (supply)" refers to whether the construction entity is separated, and the owner is a manager. "Diversity" refers to whether the management subject is separated, and if the owner is also the constructor or the manager. "Construction" is whether the management entity is connected and managed by the management entity and can be evaluated in "Good", "Middle", and "Bad" level. As a summary, even if the existing public rental housing in Korea can be separated into a skeleton and infill system, the result suggested that it has a limitation on response to residential demand. In addition, the paper was able to propose an improved plan to make the infill as a secondary operator.

• Journal of Korean Society for Atmospheric Environment
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• v.13 no.1
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• pp.65-77
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• 1997

A theoretical and numerical investigation on the boundary-layer flow over a two- or three-dimensional hill is presented. The numerical model is based on the finite volume method with boundary-fitted coordinates. The k-$\varepsilon$ turbulence model with modified wall function and the low-Reynolds-number model are employed. The hypothesis of Reynolds number independency for the atmospheric boundary-layer flow over aerodynamically rough terrain is confirmed by the numerical simulation. Comparisons of the mean velocity profiles and surface pressure distributions between the numerical predictions and the wind-tunnel experiments on the flow over a hill show good agreement. The linear theory provides generally good prediction of speed-up characteristics for the gentle-sloped hills. The flow separation occurs in the hill slope of 0.5 and the measured reattachment points are compared with the numerical prediction. It is found that the k- $\varepsilon$ turbulence model is reasonably accurate in predicting the attached flow, while the low- Reynolds-number model is more suitable to simulate the separated flows.ows.

• Journal of Electrical Engineering and Technology
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• v.6 no.1
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• pp.94-103
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• 2011

This paper presents a novel bearingless switched reluctance motor (BLSRM) with decoupled torque and suspending stator poles. BLSRM is different from conventional bearingless switched reluctance motors (SRMs) because its suspending poles are separated from the torque poles. Perpendicularly placed suspending poles are designed to produce a continuous radial force to suspend the rotor. Due to the independent suspending and torque poles, BLSRM produces a suspending force with excellent linearity according to the rotor position and independent characteristics of the torque current. The air-gap is easier to control than in conventional SRMs with their linear and independent characteristics. Furthermore, to verify the proposed structure, a mathematical model for the suspending force is derived. Finite element analysis is also employed to compare BLSRM and conventional SRMs expressions of suspending force. A prototype motoris designed and manufactured to verify the effectiveness of the proposed bearingless structure.

• Journal of the Korean Professional Engineers Association
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• v.18 no.2
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• pp.1-5
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• 1985

In the flood prediction research, it is pointed out that the difficulty of flood prediction is the frequently experienced overestimation of flood peak. That is caused by the rainfall prediction difficulty and the nonlinearity of hydrological phenomena. Even though the former reason will remain still unsolved, but the latter one can be possibly resolved the method of the AMRA (Auto Regressive Moving Average) model for each runoff component as developed by Dr. Hino and Dr. Hasebe. The principle of the method consists of separating though the numerical filters the total runoff time series into long-term, intermediate and short-term components, or ground water flow, interflow, and surface flow components. As a total system, a hydrological system is a non-linear one. However, once it is separated into two or three subsystems, each subsystem may be treated as a linear system. Also the rainfall components into each subsystem a estimated inversely from the runoff component which is separated from the observed flood. That is why flood prediction can be done without rainfall data. In the prediction of surface flow, the Kalman filter will be applicable but this paper shows only impulse function method.

• Tunnel and Underground Space
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• v.12 no.3
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• pp.210-219
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• 2002

In the ground vibration due to demolition blasting vibration and impact vibration of collapsed structure are separated. In this paper, model structures were collapsed by blasting with different charge locations. Ground vibrations were measured and separated as blasting and impact vibrations by waveform and dominant frequency. Vibration characteristics of different charge locations were examined.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.28 no.1C
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• pp.37-46
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• 2003

As Information Security Technology has become rather transparent, wide, and integrated than in part, exclusive, and separated, A necessity of the study about integrating the separated distributed security systems into one module, has grown However, there is no integrated framework which can manage all separate security systems as one integrated one yet. Accordingly, we propose a new policy based network admirustrative model in this paper which can integrate individual security systems and distributed control way into one effectively.

• Journal of applied mathematics & informatics
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• v.11 no.1_2
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• pp.291-304
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• 2003

Inventory of differential (both good And defective) items purchased in a lot for two shops under a single management is considered here. In the primary shop, the lot is received and separated, only good units are sold and shortages are allowed which are backlogged from the good units specially purchased at the beginning of the next cycle. The separated defective units are continuously transferred and sold at a reduced price from the secondary shop. This inventory model is formulated and illustrated numerically for three scenarios depending upon the time periods of the shops. Inventory, deterioration, two shops.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.21 no.45
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• pp.201-213
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• 1998

We address the problem of choosing the most economic mean value for an automatic filling operation on a production line through the sampling inspection. If quality characteristic of a unit is less than inspection specification then the goods is not accepted. Otherwise, it is accepted. The lots that the numbers of non-conforming units in a sample are larger than the allowable number of non-conforming units are rejected. The non-conforming units in the rejected lots are separated by the screening inspection. The non-conforming units separated are sold in discount price. We assume that quality characteristic is larger-the-better characteristic, the distribution of quality characteristic is normal distribution, and the standard deviation of the distribution is known. This paper presents total expected profit function model considering sales revenue, inspection costs, and material costs. The manufacturing process mean value maximizing total expected profit is determined, and the results of the process target value and total expected profit is analyzed as coefficients change.

• 제어로봇시스템학회:학술대회논문집
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• 1992.10b
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• pp.446-451
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• 1992

In this paper, we propose a method to manage production system easily for operators when either equipments or products are changed. And we explain the scheduling AI tool which realizes the proposal method. The tool's knowledge expression consists of models, rules, mathematical expression and fuzzy logic. The model expresses the relations between products and manufacture, and properties of products. The models are separated into three type, equipment model, operation model, and product model. These models are classified by applicable fields as the assembly process or continuous plant process, The model expression of each type is based on object oriented paradigm. We report systems utilizing our approach.