• Title/Summary/Keyword: and system dynamics

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US, China and the Russo-Ukraine War: The Conditions for Generating a Mutually Perceived Hurting Stalemate and Consequent Ceasefire In Moscow and Kyiv

  • Benedict E. DeDominicis
    • International Journal of Advanced Culture Technology
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    • v.11 no.4
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    • pp.177-192
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    • 2023
  • A prerequisite for a lasting ceasefire is the emergence of a prevailing view in Moscow and Kyiv that the fighting has reached a hurting stalemate. In sum, they both lose more through continuing warfare than by a ceasefire. This study applies social identity dynamics of nationalism to this escalatory conflict. It generates findings that imply that China as a third-party great power intervening mediator can potentially play a pivotal role. Shifting the respective prevailing views in Moscow and Kyiv of their interaction from a zero-sum foundation requires proffering powerful economic and political third-party incentives. Effective inducement would facilitate national defense, development and prestige for Moscow as well as Kyiv. China arguably has the underutilized potential power capabilities necessary to alter the respective prevailing views of strategic relationships among the great powers within Moscow, Brussels and Washington. A prerequisite for success in striving effectively towards this strategic goal is cooperation with the Beijing despite skepticism from Washington. This study utilizes a process tracing methodological approach. It highlights that the foundations of the Russo-Ukraine war lie in the institutionalization within Euro-Atlantic integration of the Cold War assumption that the USSR was an imperialist revisionist actor. Russia is the USSR's successor state. Moscow's prevailing view is that Russian national self-determination was unjustly circumscribed in the multinational Soviet totalitarian Communist system. The Euro-Atlantic community is perceived as a neocolonial imperial threat by allying with post-1991 Ukrainian nationalism at Russia's expense. The study finds that acknowledging Eurasian regional multipolarity is necessary, if not sufficient, to coopt Beijing into a global political stabilization strategy. It functionally aims to promote international balancing to lessen potentials for horizontal as well as vertical escalation of the Russo-Ukrainian conflict.

Standard Strategies for Convergence Industries: A Case of Clash between Electric Vehicle Charging Standards and Smart Grid Communication Standards (미래 융합산업 표준 전략: 전기 자동차 충전 표준과 스마트그리드 통신 표준 충돌 사례)

  • Huh, Joon;Lee, Heejin
    • Journal of Technology Innovation
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    • v.23 no.3
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    • pp.137-167
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    • 2015
  • Based on the stakeholder theory, this paper analyzes a clash of standards in Korea's Electric Vehicle(EV) market, particularly between an EV charging standard and a smart grid communication standard in 2012~2013. For charging, EV is connected with the electric power grid and simultaneously exchanges data regarding the charging status. When EV is connected with the power grid, a clash between two standards may arise. It actually happened when BMW entered into the Korean EV market with the DC Combo charging system. In that course, the frequency interference occurred between the EV data communication technology adopted by BMW and the AMI(Advanced Metering Infrastructure) for the smart grid system in Korea. Standardization of Korea's EV charging systems was required to solve this problem. However, it had been delayed due to the confrontation between various stakeholders involved in the process of standardization. It lasted until the DC combo was accepted as one of the Korea EV charging standards(KSAE SAE 1772-2040, 2014.1) by KSAE(The Korea Society of Automotive Engineers) in January 2014. This is an interesting case in the age of convergence. As it deals with the standard competition not among EV standards, but a clash between the EV industry and the smart grid, i.e. electric power industry, it addresses the necessity to consider standardization processes between different industries. This study draws on the stakeholder theory to analyse the dynamics of the standard clash between EV charging systems and the smart grid system, which is a unique example of standard clash between different industries. We expect such clashes to increase in the age of convergence.

A Numerical Calculation for the Optimum Operation of Cyclone-based Combustion System (선회류 방식 연소시스템의 최적 조업을 위한 수치해석)

  • Kim, Min-Choul;Lee, Jae-Jeong;Lee, Gang-Woo;Kim, Ji-Won;Shon, Byung-Hyun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.12 no.2
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    • pp.1005-1012
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    • 2011
  • This research carried out a 3-dimensional simulation using computerized fluid dynamics (CFD) for the flow characteristics, temperature distribution, velocity distribution and residence time, etc. in a reactor in order to derive the optimal combustion conditions of an innovative combustion system. The area-weighted average temperature of the outlet of a furnace during combustion at a condition of fuel input rate 1.5 ton/hr, residence time 1.25 sec and air/fuel ratio 2.1 was $1,077^{\circ}C$, which is a suitable temperature for energy recovery and treatment of air pollutants. Exhaust gas is discharged through a duct at a 40~50 m/s maximum speed along strong vortexes at the center of a combustion chamber, so strong turbulence is created at the center of a combustion chamber to enhance the combustion speed and combustion efficiency. In this system, the optimum operation conditions to prevent incomplete combustion and suppress the formation of thermal NOx were air/fuel ratio 1.9~2.1 and fuel input rate 1.25~1.5 ton/hr.

Effect of Inlet Shape on Thermal Flow Characteristics for Waste Gas in a Thermal Decomposition Reactor of Scrubber System (반도체 폐가스 처리용 열분해반응기의 입구형상이 열유동 특성에 미치는 영향에 관한 수치해석 연구)

  • Yoon, Jonghyuk;Kim, Youngbae;Song, Hyungwoon
    • Applied Chemistry for Engineering
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    • v.29 no.5
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    • pp.510-518
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    • 2018
  • Recently, lots of interests have been concentrated on the scrubber system that abates waste gases produced from semiconductor manufacturing processes. An effective design of the thermal decomposition reactor inside a scrubber system is significantly important since it is directly related to the removal performance of pollutants and overall stabilities. In the present study, a computational fluid dynamics (CFD) analysis was conducted to figure out the thermal and flow characteristics inside the reactor of wet scrubber. In order to verify the numerical method, the temperature at several monitoring points was compared to that of experimental results. Average error rates of 1.27~2.27% between both the results were achieved, and numerical results of the temperature distribution were in good agreement with the experimental data. By using the validated numerical method, the effect of the reactor geometry on the heat transfer rate was also taken into consideration. From the result, it was observed that the flow and temperature uniformity were significantly improved. Overall, our current study could provide useful information to identify the fluid behavior and thermal performance for various scrubber systems.

Dynamics of Total Phosphorus and Attached Bacteria in a Porous Medium Concentrating Nutrients from Low-Nutrient Water (저농도 영양염류를 농축하는 여재에서 총인과 부착세균의 변화)

  • Kim, Ju-Young;Nam, Jong-Hyun;Jung, Da-Woon;Cho, Ahn-Na;Choi, Seung-Ik;Ahn, Tae-Seok
    • Korean Journal of Microbiology
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    • v.45 no.2
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    • pp.133-139
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    • 2009
  • A nutrient-concentrating system was operated to retrieve total phosphorus efficiently from a non-point pollution source. Attached bacteria were expected to play an important role in the system. Phosphorous was concentrated by formation of bacterial biofilms on rubberized coconut fiber media of the system. While concentration of total phosphorus (TP) ranged merely 0.12~0.35 mg/L in the stream water, TP levels in pore water and the media were 0.45~0.86 mg/L and 40.91~242.71 mg/kg, respectively. Total bacterial number (TBN) ranged $0.3\sim2.3\times10^6$ cells/ml in stream water, $0.4\sim4.4\times10^6$ cells/ml in pore water and $0.8\sim1.9\times10^9$ cells/g in media. There was a close correlation between TP and TBN. Based on band profiles in DGGE analyses, bacterial communities in the media were different from that in the stream water. Clostridium spp. were abundant in the stream water while Aquabacterium spp. were dominant species in early stages of biofilm formation in the media. The genera predominant in matured biofilms of the media were Clostridium and Enterococcus.

Sex Steroid Hormone and Ophthalmic Disease (성호르몬과 안질환)

  • Kim, Jin-Ju;Yu, Hyeong-Gon;Ku, Seung-Yup
    • Clinical and Experimental Reproductive Medicine
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    • v.37 no.2
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    • pp.89-98
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    • 2010
  • Sex and its tropic hormones influence the lacrimal system, corneal anatomy and disease, aqueous humor dynamics and glaucoma, crystalline lens and cataract, and retinal disease. Dry eye occurs especially frequently during pregnancy, oral contraceptive use, and after menopause, during which androgen levels decrease. Androgen control development, differentiation, and lipid production of sebaceous glands throughout the body, and androgen deficiency also leads to meibomian gland dysfunction and evaporative dry eye. On the other hand, estrogen causes a reduction in size, activity, and lipid production of sebaceous glands. Sex and its tropic hormones also influence the corneal anatomy and disease, and corneal thickening occurred on the second day of the menstrual cycle and around the time of ovulation and appeared to be related to estrogen levels. Fuchs' dystrophy is more commonly seen in postmenopausal women than men and may be linked to hormonal changes that occur with aging. In addition, overexpression of estrogen and progesterone receptors in the conjunctiva of vernal keratoconjunctivitis patients. Serum progesterone levels also may be associated with intraocular pressure especially in pregnant women, and for the women. For women with cataracts, hormone levels were typical of menopause, and there was a significant negative correlation between estradiol and follicular stimulating hormone levels. In addition, serum testosterone levels are associated with the development of diabetic retinopathy. Although the role of sex hormones on the eye is largely unknown, and the results should be interpreted with caution until replicated, the functions of sex hormones in ocular disease remains to be investigated, because they may be involved in structure and function of the ocular components, which are important in the pathogenesis of ocular disease.

A Study on the Changes in Characteristics of Trade Freights and the Status as a Gateway of Busan Port between 1991 and 2010 (수출입 화물 특성과 무역관문의 위상에서 본 부산항의 변화, 1991~2010년)

  • Lee, Jung-Yoon
    • Journal of the Korean association of regional geographers
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    • v.18 no.1
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    • pp.55-70
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    • 2012
  • Busan port has played a part as the main trade gateway in Korea for several decades. However, due to the rapid integration of China into the global economy and the grand changes in global trade structures, the trade gateway system in Korea and the status of Busan port have been transformed. Busan port's role as a trade gateway toward Japan and U.S. has increased during last two decades but, in cases of China, its importance has relatively decreased. Moreover, Busan port's competitiveness has been undermined in the most part of commodity trade. These phenomena reflect the high competition among trade ports which tend to increase the effectiveness of supply chains. Based on the geographical research tradition which has understood a port as a nexus between hinterland and foreland, this study focuses the changes in characteristics of trade freights and the status as a gateway of Busan port. This approach will contribute to the understandings of dynamics in the comtemporary international logistics.

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A Numerical Study on the Factors of the Flow Hunting in a Orifice Meter (오리피스 유량계의 유동헌팅 영향인자에 관한 전산유체역학적 연구)

  • Shin, Chang-Hoon
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.36 no.4
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    • pp.449-455
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    • 2012
  • During the measurement of the flow rate of gases such as natural gas, flow hunting is observed in most orifice meters but the intensity of flow hunting at each metering system shows different characteristics. In order to investigate why such a difference occurs and whether the difference actually influences metering error, pipeline network analysis on the main factors and characteristics of flow hunting was carried out in a previous study. Following this, in this study, computational fluid dynamics (CFD) analysis was carried out to clarify the relation between flow instability and flow hunting and determine the factors influencing the orifice meter depending on the intensity of upward pressure fluctuation, time interval, and flow rate. Finally, we showed that the pressure hunting rate is a function of the ratio of the pressure difference before and after an orifice meter. On the basis of CFD analysis results, we also presented some major factors and relations influencing flow hunting.

Ontology-Based Dynamic Context Management and Spatio-Temporal Reasoning for Intelligent Service Robots (지능형 서비스 로봇을 위한 온톨로지 기반의 동적 상황 관리 및 시-공간 추론)

  • Kim, Jonghoon;Lee, Seokjun;Kim, Dongha;Kim, Incheol
    • Journal of KIISE
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    • v.43 no.12
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    • pp.1365-1375
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    • 2016
  • One of the most important capabilities for autonomous service robots working in living environments is to recognize and understand the correct context in dynamically changing environment. To generate high-level context knowledge for decision-making from multiple sensory data streams, many technical problems such as multi-modal sensory data fusion, uncertainty handling, symbolic knowledge grounding, time dependency, dynamics, and time-constrained spatio-temporal reasoning should be solved. Considering these problems, this paper proposes an effective dynamic context management and spatio-temporal reasoning method for intelligent service robots. In order to guarantee efficient context management and reasoning, our algorithm was designed to generate low-level context knowledge reactively for every input sensory or perception data, while postponing high-level context knowledge generation until it was demanded by the decision-making module. When high-level context knowledge is demanded, it is derived through backward spatio-temporal reasoning. In experiments with Turtlebot using Kinect visual sensor, the dynamic context management and spatio-temporal reasoning system based on the proposed method showed high performance.

A Numerical Study of the Effect of Sprinkler Spray on the Flow Characteristics Induced by Fire (스프링클러 분무가 화재유동특성에 미치는 영향에 관한 수치해석 연구)

  • Kim, Sung-Chan
    • Fire Science and Engineering
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    • v.26 no.5
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    • pp.105-110
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    • 2012
  • The present study investigates the effects of sprinkler spray on fire driven flow characteristics in a compartment based on numerical approach. The FDS (Fire Dynamics Simulator), a widely used fire field model, was used to simulate the fire induced flow and sprinkler spray and a series of grid independence tests have been performed to obtain the optimal grid size. In order to validate the result predicted by FDS model, the calculated results were compared with experimental results of Magnone et al.. The FDS model matches quite well to experiments in temperature profile and mass flux through doorway, however, the discrepancy between the FDS model and experiments increases with increasing water discharge rate. As with previous study, the FDS calculation also shows a decrease of mass flow rate of combustion products through doorway due to the sprinkler spray. This study can contribute to optimize the sprinkler system design and verify the validity of the fire field model with sprinkler spray.