• Title/Summary/Keyword: Gravity system

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The effect of managerial characteristics of franchisor on the perceived justice of franchisee (가맹본부의 관리적 특성이 창업 가맹점주의 공정성 인지도에 미치는 효과)

  • Kim, Gil-Sun;Ahn, Kwan-Young
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.7 no.2
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    • pp.157-165
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    • 2012
  • The specific gravity is heavily focused on the service industry in the economic development of domestic and overseas in these days. This will be predicted to increase persistently in the future society. Therefore the franchise system has been diffused as one of a management methods for these service industry. The franchise system is an advanced country's circulation system which has been populated in an advanced country. After the opening of circulation market, rapid growing trend has been showing on foreign country's popular brands in the local domestic market. So the franchise system has been largely focused on among the domestic manufacturing and the circulation companies. This study is to review how the management characteristics(headquarters' supports, communication, menu development, compensation) will affect the fairness perception of franchisee owner. The results of my study are as follows; It appeared that communication, menu development and compensation affected all the distribution fairness and the procedure fairness affirmatively.

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An Experimental Study on Flow Distributor Performance with Single-Train Passive Safety System of SMART-ITL (SMART-ITL 1 계열 피동안전계통을 이용한 유동분사기 성능에 대한 실험연구)

  • Ryu, Sung Uk;Bae, Hwang;Yang, Jin Hwa;Jeon, Byong Guk;Yun, Eun Koo;Kim, Jaemin;Bang, Yoon Gon;Kim, Myung Joon;Yi, Sung-Jae;Park, Hyun-Sik
    • Journal of Energy Engineering
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    • v.25 no.4
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    • pp.124-132
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    • 2016
  • In order to estimate the effect of flow distributors connected to an upper nozzle of CMT(Core Makeup Tank) on the thermal-hydraulic characteristics in the tank, a simplified 2 inch Small Break Loss of Coolant Accident(SBLOCA) was simulated by skipping the decay power and Passive Residual Heat Removal System(PRHRS) actuation. The CMT is a part of safety injection systems in the SMART (System Integrated Modular Advanced Reactor). Each test was performed with reliable boundary conditions. It means that the pressure distribution is provided with repeatable and reproducible behavior during SBLOCA simulations. The maximum flow rates were achieved at around 350 seconds after the initial opening of the isolation valve installed in CMT. After a short period of decreased flow rate, it attained a steady injection flow rate after about 1,250 seconds. This unstable injection period of the CMT coolant is due to the condensation of steam injected into the upper part of CMT. The steady injection flow rate was about 8.4% higher with B-type distributor than that with A-type distributor. The gravity injection during hot condition tests were in good agreement with that during cold condition tests except for the early stages.

ECSS E70 Standard for developing common EGSE and MCS (전기지상지원장비 및 관제시스템 통합 개발을 위한 유럽 표준안 현황)

  • Huh, Yun-Goo;Choi, Jong-Yeoun
    • Current Industrial and Technological Trends in Aerospace
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    • v.6 no.1
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    • pp.56-64
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    • 2008
  • Although the EGSE (Electrical Ground Support Equipment) and MCS (Mission Control System) have many similar or even identical functions, the EGSE used for assembly, integration and validation phase and the MCS for the mission operations phase are normally developed separately and used by different groups of engineers. However, the common ground system for EGSE and MCS has developed and many space missions such as PROBA (PRoject for On-Board Autonomy), ROSETTA, MARS EXPRESS, CRYOSAT (Cryosphere Satellite), GOCE (Gravity field and steady state Ocean Circulation Explorer), and GALILEO have used or will use it to minimize risk, reduce cost and improve overall product quality. It is based on ECSS (European Cooperation for Space Standards) E70 which is the international standard for ground systems and operations published by ECSS E70 Working Group. The ECSS E70 contains the basic rules, principles and requirements applied to the engineering of the ground systems and the execution of mission operations. This paper introduces standardization policy, organization and standard documentation in ECSS. The overview of ECSS E70 such as status, purpose and contents is also described in this paper.

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Treatment Level and Reactions of a Treatment Pond System Purifying Sinyang Stream Water (신양천 하천수정화 연못시스템의 처리수준 및 연못반응)

  • Yang, Hongmo
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.8 no.6
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    • pp.1-12
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    • 2005
  • Treatment level and pond reactions of a pond system were examined from May to October 2002. The system was constructed in July 2000 for purifying water of Sinyang stream that flows into Koheung Estuarine Lake located in the southern part of the Korean Peninsula. The system was composed of a primary and a secondary pond in series and established on the rice field near the lake. Water pumped from the stream was funneled into the primary pond, whose effluent was discharged into the secondary pond by gravity flow. Effluent from the secondary pond was funneled into wetlands. About 130 $m^3$/day of water was pumped into the primary pond and detention time of the primary and secondary pond was about 2 days. DO from the surface to the 1.0 m depth of the primary and secondary pond was in the rage of 5.2 to 11.0 mg/L and 4.3 to 0.7 mg/L, respectively. DO at the bottom layer of the primary pond was 0 mg/L and that of the secondary pond ranged 3.0~4.7 mg/L. The primary pond functioned as a facultative pond and the secondary as an aerobic one. The temperature difference between the surface and bottom layers of the ponds in August was about $2.5^{\circ}C$ and that in May and October was about $1.0^{\circ}C$. Thermocline was observed in the primary pond during the high ambient temperature of August. The sludge depth of the primary pond in May, August, and October was 2.4, 1.9, and 2.2 cm, respectively. That of the secondary pond was 1.2, 1.0, and 1.1 cm, respectively. SS, $BOD_5$, T-N, and T-P concentrations in influent averaged 16.64, 6.71, 6.21, and 0.23 mg/L and those in effluent from the primary pond averaged 11.48, 4.97, 4.81, and 0.17 mg/L, respectively. The removal rates of the primary pond for SS, $BOD_5$, T-N and T-P were 31%, 26%, 22%, and 24%, respectively. Average concentrations of SS, $BOD_5$, T-N, and T-P in effluent from the secondary pond were 9.81, 4.07, 4.03, and 0.14 mg/L, respectively and the abatement rates of the secondary pond for SS, $BOD_5$, T-N and T-P were 20%, 12%, 13%, and 15%, respectively. SS, $BOD_5$, T-N and T-P concentrations in effluent from the primary pond were significantly low(p=0.001) when compared with those from the secondary one.

Whole Structure of the Photoreceptors in the Ascidian Larva Visualized by an Antibody Against Arrestin (Ci-Arr)

  • Horie, Takeo;Nakagawa, Masashi;Orii, Hidefumi;Tsuda, Motoyuki
    • Journal of Photoscience
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    • v.9 no.2
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    • pp.272-274
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    • 2002
  • The anterior brain vesicle of ascidian larvae contains two distinct pigment cells. Ultrastructure of these pigment cells has been shown that the anterior pigment cell is an otolith for perception of gravity and the posterior pigment cell is an ocellus for light reception. The larva has remarkably simple central nervous system (CNS) composed of about 330 cells. We focused to study neural networks of visual systems. In the present paper, we report the whole structure of the photoreceptors of the ascidian larva visualized by an antibody against arrestin. Visual arrestin is the key protein for the termination of phototransduction and one of the abundant proteins in photoreceptors. Recently, we cloned an arrestin homologue gene, Ci-arr and the expression of Ci-arr was found to be restricted to the photoreceptors in the ocellus. To study the whole structure of the photoreceptors in the larva, we prepared an antibody against Ci-Arr. It is found that anti Ci-Arr antibody specifically stains the photoreceptors, including the cell bodies, the axons, and the nerve terminals. The photoreceptor cell bodies lies in row outside the pigment cup which penetrate the pigment cell and is continuous with the outer segments of the photoreceptor cell, inside the concavity of the pigments. The axons form bundle into a single tract. The tract extends toward the midline, where the nerve terminals diverge and seem to form synapses

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An assessment on feasibility of flotation as a secondary clarifier of an activated sludge process (생물반응공정에 대한 고액분리조로서 부상공정의 적용성 평가)

  • Chung, Chong Min;Kim, Yun Jung;Cho, Kang Woo;Lee, Sang Hyup;Hong, Seok Won;Chung, Tai Hak
    • Journal of Korean Society of Water and Wastewater
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    • v.22 no.5
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    • pp.551-559
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    • 2008
  • An experimental study was carried out to evaluate the potential of flotation process for the secondary clarifier of an activated sludge process. Flotation techniques, applied in this study, include electrofloation (EF) which generated fine bubbles smaller than $35{\mu}m$ in average and diffuser flotation (DF) which generated fine bubbles smaller than $55{\mu}m$ in average. The batch experiments were done with activated sludge displaying various characteristics. It was shown that the efficiency of solids/liquid separation was reduced as the diluted sludge volume index ($DSVI_{30}$) of activated sludge increased. The dependency, however, gradually decreased as the gas to solids (G/S) ratio increased. Thickening efficiency of EF was more than 2~10 times and DF process was more than 1.5~5 times as compared with gravity sedimentation (GS). Stable sludge blanket was maintained regardless of sludge settleability when the G/S ratio was 0.019 in the EF. On the other hand, Serious deterioration in the sludge blanket was observed in the DF depends on G/S ratio and sludge settleability. And For EF and DF, the suspended solids concentration of effluent was not nearly influenced on settleability of activated sludge and more clear than GS. A biological nutrient removal (BNR) process, combined with EF as a secondary clarifier was operated for three months. The mean MLSS (mixed liquid suspended solids) concentration in the reactor and mean solids concentration of return sludge were estimated to be 5,340 mg/L and 16,770 mg/L, respectively. The water quality of effluent was considerably stable and low value was accomplished, that was, standard suspended solids concentration $0.07{\pm}0.51mg/L$ and standard turbidity $1.44{\pm}0.56NTU$. The EF could be applicable for enhancement of efficiency of activated sludge system as well as improvement of the water quality of effluent.

Vision based Fast Hand Motion Recognition Method for an Untouchable User Interface of Smart Devices (스마트 기기의 비 접촉 사용자 인터페이스를 위한 비전 기반 고속 손동작 인식 기법)

  • Park, Jae Byung
    • Journal of the Institute of Electronics and Information Engineers
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    • v.49 no.9
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    • pp.300-306
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    • 2012
  • In this paper, we propose a vision based hand motion recognition method for an untouchable user interface of smart devices. First, an original color image is converted into a gray scaled image and its spacial resolution is reduced, taking the small memory and low computational power of smart devices into consideration. For robust recognition of hand motions through separation of horizontal and vertical motions, the horizontal principal area (HPA) and the vertical principal area (VPA) are defined respectively. From the difference images of the consecutively obtained images, the center of gravity (CoG) of the significantly changed pixels caused by hand motions is obtained, and the direction of hand motion is detected by defining the least mean squared line for the CoG in time. For verifying the feasibility of the proposed method, the experiments are carried out with a vision system.

Estimation of Safety Area for Intercept Debris by Using Modeling and Simulation (탄도탄 요격시험 안전구역 산출을 위한 모델링 및 시뮬레이션)

  • Lee, Sungkyun;Go, Jinyong;Han, Yongsu;Kim, Changhwan
    • Journal of the Korea Society for Simulation
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    • v.29 no.1
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    • pp.1-9
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    • 2020
  • The ballistic missile threat continues to increase with the proliferation of missile technology. In response to this threat, many kinds of interceptors have been emphasized over the years. For development of interceptor, systematic flight tests are essential. Flight tests provide valuable data that can be used to verify performance and confirm the technological progress of ballistic missile defense system including interceptor. However, during flight tests, civilians near the test region could be risk due to a lot of intercept debris. For this reason, reliable estimate of safety area for the flight tests should be preceded. In this study, prediction of safety area is performed through modeling and simulation. Firstly, behaviors of ballistic missile and interceptor are simulated for those entire phase including interception to obtain the relative intercept velocity and the relative impact angle. By using obtained data of kinetic energy, the fragment ejection velocity is calculated and fragment trajectories are simulated by considering drag, gravity and wind effects. Based on the debris field formation and hazard evaluation of debris, final safety area is calculated.

Assessment of damages on a RC building after a big fire

  • Ada, Mehmet;Sevim, Baris;Yuzer, Nabi;Ayvaz, Yusuf
    • Advances in concrete construction
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    • v.6 no.2
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    • pp.177-197
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    • 2018
  • This paper presents a case study about the damages on the structural elements of a cast in place reinforced concrete (RC) building after a big fire which was able to be controlled after six hours. The fire broke off at the $2^{nd}$ basement floor of the building, which has five basements, one ground, and two normal floors. As a result of intensely stocked ignitable materials, it spread out to the all of the upstairs. In visual inspection, most of the typical fire damages were observed (such as spalling, net-like cracks, crumbled plasters, bared or visible reinforcement). Also, failures of the $2^{nd}$ basement columns were encountered. It has been concluded that the severity failures of the columns at the $2^{nd}$ basement caused utterly deformation of the building, which is responsible for the massive damages on the beam-column connections. All of the observed damages were categorized related to the types and presented separated regarding the floors. Besides to the visual inspection, the numerical analysis was run to verify the observed damaged on the building for columns, beams, and the connection regions. It is concluded from the study that several parameters such as duration of the fire, level of the temperature influence on the damages to the RC building. Also, it is highlighted by the study that if the damaged building is considered on the overall structural system, it is not able to satisfy the minimum service requirements neither gravity loads nor earthquake conditions.

A 5-DOF Ground Testbed for Developing Rendezvous/Docking Algorithm of a Nano-satellite (초소형 위성의 랑데부/도킹 알고리즘 개발을 위한 5자유도 지상 테스트베드)

  • Choi, Won-Sub;Cho, Dong-Hyun;Song, Ha-Ryong;Kim, Jong-Hak;Ko, Su-Jeong;Kim, Hae-Dong
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.43 no.12
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    • pp.1124-1131
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    • 2015
  • This paper describes a 5-dof ground testbed which emulates micro-gravity environment for developing Rendezvous/docking algorithm of a nano-satellite. The testbed consists of two parts, the low part which eliminates friction force with ground and the upper part which has 3-dof rotational motion with respect to the low part. For Vison-based autonomous navigation algorithm, we use camera, LIDAR and AHRS as sensors and eight cold gas thrusters and three axis directional reaction wheels as actuators. All system software are implemented with C++ based on on-board computer and Linux OS.