• Title/Summary/Keyword: confined system

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A Development of Evaluation System on Technological Information Analysis by Retired Scientists & Engineers (고경력/퇴직 과학기술자의 기술정보분석 실적평가 방안)

  • 김석진;조흥곤;유영복;민완기
    • Journal of Korea Technology Innovation Society
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    • v.5 no.3
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    • pp.307-320
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    • 2002
  • The purpose of this paper was to design evaluation process on technological information analysis done by re-tired scientists and engineers. Existing studies on evaluation system and methodology were analyzed and their implications are as follows. To provide useful feedback to the retired scientists, indicators of evaluation should be simplified and method of evaluation confined to the quantitative one. And the results of evaluation need to be utilized in direction to encourage the old scientists and engineers.

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Parameters Estimation and Analysis for Leaky Aquifer System (누수대수층에 대한 수리상수 추정과 해석)

  • 김민환
    • Journal of the Korean Society of Groundwater Environment
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    • v.5 no.3
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    • pp.123-128
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    • 1998
  • Leaky aquifer (two-aquifer) system in this study consist of an upper unconfined and a lower confined aquifer with a leaky layer between them. It is assumed that water is withdrawn from the confined aquifer of the aquifer system, the upper unconfined aquifer will be affected by the leaky aquifer separating the upper and lower aquifer. In order to analyze the leaky aquifer, the determination of hydraulic parameters is needed. In this paper, hydraulic parameters are suggested by improved SM (slope-matching) method. To know variation of groundwater head in leaky aquifer systems, an numerical scheme is made using the finite difference method. To verify the numerical scheme, its solution is compared to analytical one. The solution of them agrees well in one-dimensional system at steady-state condition. And heads of groundwader are computed upper and lower aquifer in two-dimensional system.

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Effects of confinement on physiological and psychological responses and expression of interleukin 6 and brain derived neurotrophic factor mRNA in primiparous and multiparous weaning sows

  • Zhang, Mingyue;Li, Xiang;Li, Jianhong;Sun, Hanqing;Zhang, Xiaohui;Bao, Jun
    • Asian-Australasian Journal of Animal Sciences
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    • v.30 no.9
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    • pp.1350-1357
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    • 2017
  • Objective: The present study aimed to investigate whether the long-lasting, recurrent restricting of sows leads to the physiological and psychological reaction of discomfort. Methods: Sows (Large White) that had experienced restricting for about 0.5 or 3 years and agematched sows kept in a group housing system (loose sows) were compared. Pupillary light reflex parameters were measured at the weaning stage. Immediately after slaughter, blood samples were taken to measure serum cortisol levels, and the brain was dissected, gene expression in the hippo-campus, frontal cortex and hypothalamus was analyzed. Results: The serum cortisol levels were higher in the confined sows than in the loose sows. The full maturity, but not the young adolescent, confined sows had longer latency time in the onset of pupil constriction than their loose counterparts. Real-time polymerase chain reaction analyses revealed an increased expression of interleukin 6 mRNA in the hippocampus and decreased expression of brain derived neurotrophic factor mRNA in hippocampus and hypothalamus and to a lesser extent in the frontal cortex of the full maturity confined sows, compared with the full maturity loose sows. Conclusion: Taken together, these data indicated that recurrent restricting stress in full maturity sows leads to the physiological and psychological reaction of discomfort.

Experimental Study of Water Penetration Rate Via Graphene Oxide Membrane According to Driven Pressure Difference (산화 그래핀 맴브레인의 물투과 속도와 차압 조건 간 상관관계에 대한 실험적 연구)

  • Kim, Ji-Min
    • Journal of the Korean Society of Mechanical Technology
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    • v.20 no.6
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    • pp.858-864
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    • 2018
  • Graphene oxide (GO) laminate is a new promising material for water purification system, which has extraordinary permeability only for water molecule. It consists of numerous nano-channels, in which water molecules could be nano-confined, resulting in slip of the molecules for very fast transportation speed. In this study, water penetration rate via different thickness of GO membrane according to driven pressures are measured experimentally, so that speed of water molecules and permeability are evaluated. Generally, water penetration rate via a membrane with macroscopic-sized channel increases linearly with pressure difference between up and bottom side of the membrane, but that via GO membrane approaches asymptotic value (i.e. saturation) as like a log function. Moreover, the permeability of GO membrane was observed in inverse proportion to its thickness. Based on the experimental observations, a correlation for volume flux via GO membrane was suggested with respect to its thickness and external pressure difference.

Optimal Design of Reporting Cell Location Management System using Ranking Ant Colony System (랭킹개미군전략을 이용한 리포팅셀 위치관리시스템 최적 설계)

  • Kim, Sung-Soo;Kim, Geun-Bae
    • IE interfaces
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    • v.19 no.2
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    • pp.168-173
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    • 2006
  • In the Reporting Cell Location Management (RCLM) system, a subset of cells in the network is designated as the reporting cells. Each mobile terminal performs location update only when it enters one of these reporting cells. When a call arrives, the paging is confined to the reporting cell the user last reported and the neighboring bounded non-reporting cells. Frequent location update may result in degradation of quality of service due to interference. Miss on the location of a mobile terminal will necessitate a search operation on the network when a call comes in. We must decide the number of reporting cells and which cell should be reporting cell to balance the registration (location update) and search (paging) operations to minimize the cost of RCLM system. This paper proposes a ranking ant colony system (RACS) for optimization of RCLM system.

Interfacial Charge and Mass Transfer at Graphene-SiO2 Substrates: Raman Spectroscopic Studies

  • Ryu, Sun-Min
    • Proceedings of the Korean Vacuum Society Conference
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    • 2014.02a
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    • pp.115.1-115.1
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    • 2014
  • Atom-thick 2-dimensional materials such as graphene, h-BN and MoS2 hold substantial potential for applications in future molecular-scale integrated electronics, transparent conducting membranes, nanocomposites, etc. From a fundamental point of view, 2-dim crystal-solid substrates can also serve as a unique system to study various physicochemical phenomena occurring at low dimensions or interfaces. In this talk, I will present our recent Raman spectroscopy studies on the surface science problems of graphene: interfacial charge transfer, molecular diffusion in confined space and structural deformation.

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고에너지원을 이용한 폭발 현상 모델링

  • Lee, Gyeong-Cheol;Yoh, Jai-Ick
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2007.04a
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    • pp.349-352
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    • 2007
  • In this paper, we describe the modeling of ablation based laser applications for innovative use in the military In the laser ignition system, a metal confinement is ablated with the high intensity pulsed energy, triggering a thermal ignition of the confined high explosives. The constitutive equations for the laser source, deformation of metals, and explosion of energetic materials are described.

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On the Size of Quantum Dots with Bound Hydrogenic Impurity States

  • Sun, Ho-Sung
    • Bulletin of the Korean Chemical Society
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    • v.30 no.2
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    • pp.315-318
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    • 2009
  • Some particular bound state energies of an electron, under Coulomb potential field, confined in a two-dimensional circle and a three-dimensional sphere are analytically derived. The derivation shows that the electron cannot be bound in a negative energy state when the circle (or sphere) is smaller than a certain critical size. The critical size dependency on the strength of Coulomb potential and the angular momentum of the electron is also analytically derived. This system mimics quantum dots. Therefore the derivation provides new information on a minimum critical size of quantum dots with hydrogenic impurity.

Optimal Design of Reporting Cell Location Management System using Simulated annealing System (시뮬레이티드어닐링을 이용한 리포팅셀 위치관리시스템 최적 설계)

  • Kim, Sung-Soo;Moon, Jae-Ki
    • Journal of Industrial Technology
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    • v.28 no.B
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    • pp.9-14
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    • 2008
  • In the Reporting Cell Location Management (RCLM) system, a subset of cells in the network is designated as the reporting cells. Each mobile terminal performs location update only when it enters one of these reporting cells. When a call arrives, the paging is confined to the reporting cell the user last reported and the neighboring bounded non-reporting cells. Frequent location update may result in degradation of quality of service due to interference. Miss on the location of a mobile terminal will necessitate a search operation on the network when a call comes in. We must decide the number of reporting cells and which cell should be reporting cell to balance the registration (location update) and search (paging) operations to minimize the cost of RCLM system. This paper proposes a simulated annealing (SA) for optimization of RCLM system.

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A Study on Implementation of Hydroponics Automation System using Adaptive Fuzzy Control (적응 퍼지 제어기를 이용한 수경재배 자동화를 위한 연구)

  • 노명균;김승우;홍상은
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 1996.10a
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    • pp.111-114
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    • 1996
  • Hydroponics is to grow plants, not in soil but in water which the quantity of necessary chemical food can be controlled. In this paper, this is designed in the automatic system. The closed culture reduces cost of production and produces a many kinds of agricultural products in a confined place. An adaptive fuzzy control in the best method to solve and to overcome parametric uncertainties and non-linearity of the controlled system. A hydroponics automation system which is able to overcome these control problems. It is used in implementation of the hydroponics automation system. The performance is analyzed through an experiment in which the new adaptive fuzzy control method is applied to the automatic control of tomato hydroponics.

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