• International Journal of Advanced Culture Technology
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• 제10권4호
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• pp.470-477
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• 2022

EOTS for drones is showing another aspect of market expansion in detection and recognition areas previously occupied by artificial satellites. The two-axis EOTS for drones controls the vibration or disturbance caused by the drone during the mission so that EOTS can accurately recognize the goal. Vibration generated by drones is transmitted to EOTS. Therefore, it is essential to develop a stabilization controller that attenuates vibrations transmitted from drones so that EOTS can maintain the viewing angle. Therefore, it is necessary to standardize drone disturbance and secure the performance of EOTS disturbance attenuation controller optimized for disturbance level through this. In this paper, a method of standardizing drone disturbance applied to EOTS is studied, through which EOTS controller simulation is performed and stabilization controller shape is selected and designed.

• 기술혁신연구
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• 제12권3호
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• pp.97-109
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• 2004

According to "structure-conduct-performance" paradigm in IO, market structure (concentration) determines conduct (R&D investments), and conduct yields market performance (ratio of price to marginal cost). Previous empirical studies on Schumpeter Mark I, II assumed that the explanatory variable (market structure) and the disturbance are uncorrelated in the R&D equation. In this situation, Ordinary Least Squares (OLS) estimates of the structural parameters are inconsistent, because the endogeneous variables (R&D and market structure) can be determined simultaneously. So, in this study, full information (or system methods) estimation is used to test Schumpeter hypothesis since joint estimation can as well bring efficiency gains in the seemingly uncorrelated regressions (SUR) setting.

• The Journal of Asian Finance, Economics and Business
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• 제7권1호
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• pp.37-46
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• 2020

The paper examines the dynamic relationship of domestic credit and stock market liquidity on the economic growth of the Philippines from 1995 to 2018 applying the autoregressive distributed lag (ARDL) bounds testing approach to cointegration, together with Granger causality test based on vector error correction model (VECM). The ARDL model indicated a long-run relationship of domestic credit and stock market liquidity on GDP growth. When the GDP per capita is the dependent variable there is weak cointegration. Also, the Johansen cointegration test confirmed the existence of long-run relationship of domestic credit and stock market liquidity both on GDP growth and GDP per capita. The VECM concludes a long-run causality running from domestic credit and stock market liquidity to GDP growth. At levels, domestic credit has significant short-run causal relationship with GDP growth. As for stock market liquidity at first lag, has significant short-run causal relationship with GDP growth. With regards to VECM for GDP per capita, domestic credit and stock market liquidity indicates no significant dynamic adjustment to a new equilibrium if a disturbance occurs in the whole system. At levels, the results indicated the presence of short-run causality from stock market liquidity and GDP per capita. The CUSUMSQ plot complements the findings of the CUSUM plot that the estimated models for GDP growth and GDP per capita were stable.

• 재무관리연구
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• 제24권1호
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• pp.85-107
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• 2007

본 연구는 펀드의 수익률과 현금흐름 간에 관계를 분석함으로써, 펀드의 현금흐름에 의한 주식시장 교란이 있는지를 분석하였고, 주식형 펀드의 수익률에 영향을 줄 것으로 예상되는 결정요인들을 통계적으로 분석해 보았다. 본 연구의 표본기간은 2005년 4월부터 2006년 3월까지로 주가상승기라 펀드의 현금흐름이 뚜렷할 것으로 예상되어 설정하였다. 연구대상은 월별로 116개 펀드이며, 연구기간이 12개월이므로 최종 표본펀드는 1,392개가 된다. 먼저, 수익률과 결정요인 등과의 분석에서는 모든 펀드 유형에서 펀드의 성장성(GRW)이 증가할수록 펀드의 수익률과 초과수익률이 증가하는 것으로 나타났다. 그러나 수익률과 현금흐름과의 관계에서는 성장추구형 펀드만 현금흐름이 수익률에 대해 영향을 주었다. 이는 안정주식형 펀드는 주식편입비가 낮기 때문에 수익률이 현금흐름에 영향을 크게 안 받는 것으로 보이며, 고성장 추구형 펀드는 수익률에 미치는 현금흐름의 영향이 기대와 비기대의 혼재나 기간시차의 혼재로 인해 영향을 받지 않는 것으로 추론된다. 추가로 펀드수익률(FR)에 현금흐름 시차가 미치는 영향을 분석한 결과, 펀드의 전기 현금흐름이 펀드의 당기 수익률에는 영향을 미치지 않았다. 이는 아직까지 국내 펀드시장에서 펀드의 현금흐름에 의해 주식시장이 왜곡되어 펀드수익률의 상승으로 이어지지는 않는 것으로 보인다. 국내 펀드시장이 일천하여 향후 더 많은 표본으로 진보된 연구들이 수행됨으로써 펀드산업이 발전되어야 할 것이다.

• 한국생산제조학회지
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• 제18권6호
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• pp.565-575
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• 2009

A forklift (also called a lift truck) is a powered industrial truck that is used to lift and transport materials. It has become an indispensable piece of equipment in manufacturing and warehousing operations. The modem forklift is equipped with automatic transmission to meet the requirement of loading and easy operation of the vehicle. This paper proposes the design of TECU(Transmission Electronic Control Unit) which is applied to PSD322-Axle transmission. Garofalo's control technique is generally used to the automatic transmission. We consider the work quality and market requirement that does not want to control engine throttle. This paper proposes new controller system which guarantees efficient speed changes with simple system. This new system does not control the engine throttle spontaneously. But it has the load of engine and vehicle as a maximum disturbance. The scope of the disturbance is limited to the stoll area of the torque converter. This paper proposes a ideal control commander that converges relative velocity of the input and ouput of a clutch into a zero. We design linear controller to execute the idea control commander. We applied the control algorithm to the forklift of PSD322-Axle type and the performance of this controller was verified.

• 한국산림과학회지
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• 제95권6호
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• pp.778-783
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• 2006

표고버섯의 재배와 출하 결정에서 단기 가격의 예측은 매우 중요하다. 표고버섯 가격의 형성에는 많은 요인들이 작용하고 있기 때문에 이를 구조모형으로 예측하는 것은 어려운 일이다. Box-Jenkins 방법을 이용한 표고버섯과 모형선정 과정에서 발생할 수 있는 오류를 줄이고 경우에 따라서는 더 높은 예측력을 가지기도 한다. 이 연구는 1992~2005년의 가락시장 표고버섯 중품 가격자료를 이용하여 시계열 분석 모형을 구축하고 단기 가격을 예측한 것이다. 그리고 분석에 포함되지 않은 2006년의 실제가격과 예측결과를 비교하였다. 분석 결과는 날씨 변화의 영향으로 시장에 교란이 발생하였던 시기를 제외하면 비교적 높은 정확도를 보여 주어 모형의 유용성을 시사한다.

• 현장농수산연구지
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• 제25권4호
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• pp.78-83
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• 2024

본 연구는 일조방해에 의한 광 환경의 변화가 스프레이 국화의 생육과 개화, 절화 품질에 미치는 영향에 대해 분석하기 위해 수행하였다. 이를 위해 절화용 스프레이 국화 '옐로우캡'과 '피치팡팡' 품종을 인위적으로 차광 처리하여 무차광 대비 66% 정도의 일조를 방해하였고, 이에 따른 국화의 생육 및 개화 특성, 채화량 등을 조사하였다. 일조방해에 따른 국화의 단위면적당 채화량은 차광과 무차광 처리구에서 유의미한 차이는 없었으나, 개화소요일수는 차광 처리에서 '옐로우캡' 품종은 72.1일, '피치팡팡' 품종은 65.2일로 무차광에 비해 각각 14.1일과 8.9일 정도 개화가 지연되었다. 꽃의 크기와 꽃 수 역시 차광 처리에서 '옐로우캡'과 '피치팡팡' 두 품종 모두 각각 10%와 15%, 30%와 28% 정도 감소하였으며, 화경장은 품종별로 각각 10%와 20%, 줄기의 굵기는 23%와 37%, 절화 생체중은 32%와 33% 정도 감소하여 절화 국화의 품질이 크게 저하되었다. 본 연구의 결과에서 차광 처리한 국화의 개화가 지연됨은 물론 꽃의 크기와 꽃 수가 감소하고 절화의 길이와 생체중 등이 모두 감소한 것으로 볼 때, 인공 건축물 등에 의한 일조방해는 국화의 생장과 화아분화, 화아발달에 필요한 광량을 제한함으로써 절화의 생산성과 품질을 저하시킬 것으로 판단된다. 따라서 일조방해로 인한 국화 재배농가의 피해 구제를 위해 차광 정도에 따른 수확량 감소율 및 상품성 가치 하락률 등에 대한 추가적인 연구가 필요하다.

• 한국대기환경학회지
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• 제28권5호
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• pp.527-537
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• 2012

The increasing consumption of pseudo-petroleum products (PPP) has been disturbing the national petroleum market. The use of PPP lead to tax evasion, disturbance of sound trading principles, component corrosion of cars, and explosion accident. Also, PPP have emitted hazardous air pollutants (HAP) including the carcinogenic aromatic hydrocarbons, PAHs and aldehydes more than regular-petroleum products. It thus has potentials to cause many environmental and health care problems. In this study, benzene, toluene and xylene emissions from road transport vehicles due to the use of pseudo-gasoline are estimated for the year 2008. The results of our study provide emission estimates of benzene, toluene and xylene for the year as 405, 1,711, 717 tonne/yr, respectively for regular-gasoline. BTX emissions are calculated as 452~515, 1,882~2,264 and 732~752 tonne/yr when the amount of pseudo-gasoline is estimated to account for 6~13% for regular-gasoline consumption. BTX emissions increased as much as 12~27, 10~32, 2~5% by using pseudo-gasoline. It is found that the pseudo-gasoline should be the key component to produce HAP in urban area.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2007년도 추계학술대회 논문집
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• pp.345-351
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• 2007

The research which it sees will confront to the coating with paint material and a coating with paint public law application of the river bridge and it will present it will sleep and it will execute, it will reach and a comparison - an analysis from the research which it tries to respect middle of special environment the polyurethane system which is a method coating with paint system and fluorine resin system, against a ceramic system it executed more an objectivity and rational fundamental data. With research method against each coating with paint evening sunlight a research investigation material and structure, it separated with spatial-temporal characteristic and economic viewpoint it executed. When considering overview from material viewpoint, fluorine resin system ceramic system polyurethane system pure with it is judged with the fact that it is excellent. There is a possibility of saying that the coefficient of friction of the fluorine resin system which uses the weapon quality zinc end coating compound ever so hard and polyurethane system is excellent ceramic system than from structure viewpoint. That fluorine resin system = polyurethane system ceramic system pure with it is excellent, it is judged from spatial-temporal characteristic viewpoint. It measures but it considered an internal troubles year grudge in the standard which becomes disturbance the place where it executes the market the expectation life person of the general bridge against 100 years the result fluorine resin system polyurethane system ceramic system which compares a materials unit cost pure with it appeared.

• 대한전기학회논문지:전력기술부문A
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• 제55권12호
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• pp.505-513
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• 2006

One of the major reasons for recent blackout, like August 14, 2003 blackout in the US and Canada has been insufficient voltage/reactive power support. For the stable reactive power management, a new approach for the voltage monitoring and control structure is required in the market environment. This paper proposes the effective localized-voltage control scheme using the information from pilot buses at each zone. In this paper, the steady state voltage monitoring and control (SSVMC) is adopted and illustrated for the voltage control scheme during steady state because it is thought as the systemic algorithm to explain voltage profile phenomenon before and after contingencies. And the concept of electrical distance is applied to simultaneously achieve both clustering the voltage control zone, and selecting the pilot bus as the representative node at each control zone. Applying SSVMC based on the structure with clustering and pilot bus enables system operators to monitor and understand the system condition much more easily, to monitor and control the voltage in real-time more manageably, and to respond quickly to a disturbance. The proposed voltage control scheme has been tested on the IEEE 14-bus system with the numerical analysis to examine the system reliability and structure efficiency.