• Title/Summary/Keyword: mitigate

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Design and Control Strategy of Fuel Cell Hybrid Power System for Light Electric Railway Vehicles (경전철용 연료전지 하이브리드 동력시스템 설계 및 제어)

  • Kim, Young-Ryul;Park, Young-Won
    • Journal of the Korean Society for Railway
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    • v.12 no.5
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    • pp.772-777
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    • 2009
  • The development of fuel cell hybrid power system, as a next generation power system to promote clean energy which will mitigate the continued global warming, has demonstratd a significant progress in passenger vehicle applications. Also, in case of railway vehicles in non-electrified railway lines, the adoption of fuel cell hybrid power system is being studied among well-known manufacturers. This paper introduces both the configuration and the control strategy of fuel cell hybrid power system to apply to a light electronic railway vehicle having a repeated driving pattern of acceleration, coasting and deceleration. The simulation results demonstrate the viability of the proposed power system design and its control strategy.

MNE's Ability to Mitigate the FX Exposure: Subsidiary Network and Pass-through Ability

  • Cho, Hyejin
    • East Asian Journal of Business Economics (EAJBE)
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    • v.6 no.4
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    • pp.1-12
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    • 2018
  • Purpose - This paper tests the effect of the structure of manufacturing and marketing subsidiary network on FX exposure of Korean MNEs. Furthermore, the moderating effect of pass-through ability on the relationship between the subsidiary network and FX exposure is explored. Research design and methodology - This study utilizes a sample of 309 Korean MNEs constructed from database offered by KOTRA and KIS-VALUE. Results - As operational flexibility arising from having operations in multiple locations provides an option for firms to tackle FX exposure, greater breadth of manufacturing subsidiary network reduces FX exposure, and greater depth increases FX exposure. However, both the breadth and depth of marketing subsidiary network decrease FX exposure due to the firm's higher level of market presence and knowledge to devise an appropriate marketing strategy that can buffer adverse exchange rate movement. Such an effect is intensified when MNE's have FX exposure pass-through ability stemming from differentiated good. Conclusions - Empirical findings suggest that types and structure of Korean MNEs' foreign subsidiary network are closely related to the level of FX exposure they are experiencing. Also, they can utilize marketing subsidiary network more efficiently when having a higher R&D intensity.

New Direction of Pilot Rural Development -With Respect to Rural Settlement Zone Development Project- (새로운 시범(示範) 농촌(農村) 건설(建設) 방향(方向) - 농어촌정주생활권개발사업(農漁村定住生活圈開發事業)을 중심으로 -)

  • Lim, Jae Hwan
    • Korean Journal of Agricultural Science
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    • v.22 no.2
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    • pp.209-222
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    • 1995
  • To mitigate the development gap between urban and rural area, the government has implemented project planning as the Rural Integrated Development in each Gun level since 1986. On account of shortage of the development fund, the government had changed the Gun level development into Myeon level development so called the Rural Central Settlement Zone Development. The government had started nine pilot projects throughout Korea from 1990. This study is aimed at identifing problems that found in the course of implementation of the projects and recommending the new direction of the successful implementation of the projects in the future. The problems and directions found in the cource of project implementation were as follows: 1. Project implementation by investment priority considering economic and financial rate of return should be made. 2. Objective project planning should be made. 3. Equal allocation of the limited investment fund by group interest and egoism should be prohibited. 4. Enforcement of special man power should be taken into account. 5. Unification of the diversified existing terms and conditions of loans for house construction and improvement. 6. Road development oriented budget allocation should be improved. 7. Sufficient development fund should be procured considering the present rate of sufficiency of the project cost as 36%. 8. Sufficient supply of the credit loans for improvement of living environment of the farmers should be realized. 9. Rational implementation planning in connection with farm household income source development should be made.

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AEBS Algorithm with Tire-Road Friction Coefficient Estimation (타이어-노면 마찰계수 추정을 이용한 AEBS 알고리즘)

  • Han, Seungjae;Lee, Taeyoung;Yi, Kyongsu
    • Journal of Auto-vehicle Safety Association
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    • v.5 no.2
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    • pp.17-23
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    • 2013
  • This paper describes an algorithm for Advanced Emergency Braking(AEB) with tire-road friction coefficient estimation. The AEB is a system to avoid a collision or mitigate a collision impact by decelerating the car automatically when forward collision is imminent. Typical AEB system is operated by Time-to-collision(TTC), which considers only relative velocity and clearance from control vehicle to preceding vehicle. AEB operation by TTC has a limit that tire-road friction coefficient is not considered. In this paper, Tire-road friction coefficient is also considered to achieve more safe operation of AEB. Interacting Multiple Model method(IMM) is used for Tire-road friction coefficient estimation. The AEB algorithm consists of friction coefficient estimator and upper level controller and lower level controller. The numerical simulation has been conducted to demonstrate the control performance of the proposed AEB algorithm. The simulation study has been conducted with a closed-loop driver-controller-vehicle system using using MATLAB-Simulink software and CarSim Vehicle model.

Design of Electronic Drum Using Computer Communication Based on Arduino (아두이노에 기반한 컴퓨터 통신을 이용한 전자드럼 설계)

  • Kim, Seungmin;Yang, Jisoo;Lee, Seungjae;Kim, Jung Tae
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2013.10a
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    • pp.489-491
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    • 2013
  • In this paper, Electronic Drum based on Arduino and Processing language to communicate with a computer is implemented. First, we made a drum pad by using piezoelectric sensors. The drum pads prevent damage to the sensor and new mechanism was fabricated to mitigate the impact structure. Arduino connected to the pad, the sensor detects a signal when the shock sends it to Arduino. The received signal of Arduino sends a signal to the computer, and the signal received is stored in the computer to output sound of the drum. Through this structure, the micro-controller, the computer and communications technology can be combined and applicable to a many system.

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CURRENT RESEARCH AND DEVELOPMENT ACTIVITIES ON FISSION PRODUCTS AND HYDROGEN RISK AFTER THE ACCIDENT AT FUKUSHIMA DAIICHI NUCLEAR POWER STATION

  • NISHIMURA, TAKESHI;HOSHI, HARUTAKA;HOTTA, AKITOSHI
    • Nuclear Engineering and Technology
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    • v.47 no.1
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    • pp.1-10
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    • 2015
  • After the Fukushima Daiichi nuclear power plant (NPP) accident, new regulatory requirements were enforced in July 2013 and a backfit was required for all existing nuclear power plants. It is required to take measures to prevent severe accidents and mitigate their radiological consequences. The Regulatory Standard and Research Department, Secretariat of Nuclear Regulation Authority (S/NRA/R) has been conducting numerical studies and experimental studies on relevant severe accident phenomena and countermeasures. This article highlights fission product (FP) release and hydrogen risk as two major areas. Relevant activities in the S/NRA/R are briefly introduced, as follows: 1. For FP release: Identifying the source terms and leak mechanisms is a key issue from the viewpoint of understanding the progression of accident phenomena and planning effective countermeasures that take into account vulnerabilities of containment under severe accident conditions. To resolve these issues, the activities focus on wet well venting, pool scrubbing, iodine chemistry (in-vessel and ex-vessel), containment failure mode, and treatment of radioactive liquid effluent. 2. For hydrogen risk: because of three incidents of hydrogen explosion in reactor buildings, a comprehensive reinforcement of the hydrogen risk management has been a high priority topic. Therefore, the activities in evaluation methods focus on hydrogen generation, hydrogen distribution, and hydrogen combustion.

Design of an Organic Simplified Nuclear Reactor

  • Shirvan, Koroush;Forrest, Eric
    • Nuclear Engineering and Technology
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    • v.48 no.4
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    • pp.893-905
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    • 2016
  • Numerous advanced reactor concepts have been proposed to replace light water reactors ever since their establishment as the dominant technology for nuclear energy production. While most designs seek to improve cost competitiveness and safety, the implausibility of doing so with affordable materials or existing nuclear fuel infrastructure reduces the possibility of near-term deployment, especially in developing countries. The organic nuclear concept, first explored in the 1950s, offers an attractive alternative to advanced reactor designs being considered. The advent of high temperature fluids, along with advances in hydrocracking and reforming technologies driven by the oil and gas industries, make the organic concept even more viable today. We present a simple, cost-effective, and safe small modular nuclear reactor for offshore underwater deployment. The core is moderated by graphite, zirconium hydride, and organic fluid while cooled by the organic fluid. The organic coolant enables operation near atmospheric pressure and use of plain carbon steel for the reactor tank and primary coolant piping system. The core is designed to mitigate the coolant degradation seen in early organic reactors. Overall, the design provides a power density of 40 kW/L, while reducing the reactor hull size by 40% compared with a pressurized water reactor while significantly reducing capital plant costs.

Simulation of Multiple Steam Generator Tube Rupture (SGTR) Event Scenario

  • Seul Kwang Won;Bang Young Seok;Kim In Goo;Yonomoto Taisuke;Anoda Yoshinari
    • Nuclear Engineering and Technology
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    • v.35 no.3
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    • pp.179-190
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    • 2003
  • The multiple steam generator tube rupture (SGTR) event scenario with available safety systems was experimentally and analytically evaluated. The experiment was conducted on the large scaled test facility to simulate the multiple SGTR event and investigate the effectiveness of operator actions. As a result, it indicated that the opening of pressurizer power operated relief valve was significantly effective in quickly terminating the primary-to-secondary break flow even for the 6.5 tubes rupture. In the analysis, the recent version of RELAP5 code was assessed with the test data. It indicated that the calculations agreed well with the measured data and that the plant responses such as the water level and relief valve cycling in the damaged steam generator were reasonably predicted. Finally, sensitivity study on the number of ruptured tubes up to 10 tubes was performed to investigate the coolant release into atmosphere. It indicated that the integrated steam mass released was not significantly varied with the number of ruptured tubes although the damaged steam generator was overfilled for more than 3 tubes rupture. These findings are expected to provide useful information in understanding and evaluating the plant ability to mitigate the consequence of multiple SGTR event.

Long-Term Follow Up of Refractory Myotonia Associated with Hyperadrenocorticism in a Maltese Dog

  • Nam, Sookin;Kang, Byeong-Teck;Song, Kun-ho;Seo, Kyoung-won
    • Journal of Veterinary Clinics
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    • v.37 no.5
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    • pp.273-277
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    • 2020
  • A 12-year-old, female Maltese was referred with uncontrolled hyperadrenocorticism (HAC). Despite well management of HAC through treatment with trilostane and serial monitoring with ACTH stimulation tests for over three years, stiffness of the neck and limbs progressively worsened over time. Neurological test was performed, which showed no abnormalities of cranial nerves. Proprioception was delayed but the cause appeared to be due to stiffness of limb muscles. Muscle tone had increased over time and stiffness had worsened to the extent where it made walking difficult. MRI scans showed no orthopedic or spinal diseases, and pituitary microadenoma was confirmed with pituitary gland measurement of 6 × 6.4 × 4.5 mm (H × W × L). Electromyography presented random discharges with fluctuating amplitude and frequency, which were consistent with myotonic discharges. There were no improvements of myotonic signs despite treatment for HAC with trilostane. Supplementation of L-carnitine and coenzyme Q-10 to mitigate muscle stiffness, following diazepam and methocarbamol to help with muscle rigidity, failed to show any positive effect and the dog died a sudden death, 1,182 days after the initial visit.

Operational Improvement of Small Urban Storm Water Pumping Station (2) - Comparative Study to Reduce the Flooding Problems using Flood Simulation Model (도시 소유역 배수펌프장 운영개선 방안 연구 (2) - 침수범람모의에 의한 침수방지 방안 비교 연구)

  • Gil, Kyung-Ik;Han, Jong-Ok;Kim, Goo-Hyun
    • Journal of Korean Society on Water Environment
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    • v.22 no.1
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    • pp.110-115
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    • 2006
  • Flooding situation of Sutak basin was simulated and simulation seemed to be consistent with the real flooding situation in terms of high water levels and timings of flooding. The flood simulation model was used to evaluate alternatives to mitigate flooding problems in Sutak basin. From the evaluation of flood mitigation plans, it was found that combined operation of Sutak and Inchang pumping stations through partial diversion of inflow of Sutak pumping station to Inchang pumping station was the most effective one among the suggested mitigation plans. About 500 meter diversion channel will be needed to send 30% of Sutak pumping station inflow to Inchang pumping station. This will reduce overload of Sutak pumping station and the storage capacity of Inchang pumping station will be more efficiently utilized.