지게차용 LPG엔진의 회전수 변환에 의한 토크 증가 방안의 연구(2)

김봉현(Bonghyun Kim),신한길(Hangil Sin),박정배(Jeongbae Park),이충근(Chunggeun Lee),이대엽(Daeyup Lee) 한국자동차공학회 2019 한국자동차공학회 학술대회 및 전시회 Vol.2019 No.11

LPG having low carbon atoms can contribute to improve air quality by less emitting CO2 and lower pollutant emissions. If it is available to connect a LPG engine having a high rpm characteristic with a diesel engine transmission having a low rpm characteristics, LPG engine can be installed on a construction machine such as a forklift. An adapter that reduces the speed between the LPG engine and the forklift’s transmission can increase the torque due to the speed reduction while maintaining the high power of the LPG engine. A reduction adapter is composed of planetary gear of which reduction ratio is designed with 1.7 (input: ring gear, output: carrier), number of planetary gears. When the reduction gear adapter is applied to the forklift, the engine speed in the idling and low speed ranges cannot meet the performance requirements of the forklift because the engine speed is lowered. Therefore, there is a need for a converter capable of increasing the engine speed in the idling and low speed regions. For this purpose, an embedded system is designed and installed between the acceleration pedal and the transmission of the forklift truck to increase the speed of the accelerator pedal by increasing the signal of the accelerator pedal in the low speed region.

지게차용 LPG 엔진의 회전수 변환에 의한 토크 증가 방안의 연구

김봉현(Bonghyun Kim),정윤동(Yoondong Jeong),박정배(Jeongbae Park),이대엽(Daeyup Lee) 한국자동차공학회 2019 한국자동차공학회 부문종합 학술대회 Vol.2019 No.5

In order for a forklift to use the LPG engine of a passenger car having a large number of production, there is a problem that the range of the engine speed is too high and the torque is low. Therefore, in this study, it is aimed to develop an adapter capable of reducing the number of revolutions between the LPG engine with high rated output characteristics and the existing transmission. When the converter is used for LPG engine of a passenger car using such a converter to decelerate the rotation speed, the LPG engine having high rotation speed characteristics and high power can be used as it is, and the rotation speed range can be reduced while increasing the torque. Therefore, when a forklift using a diesel engine is replaced with a power train equipped with an LPG engine and an adapter, the power performance can be improved while increasing the torque.

전통탑에 대한 실감형 3D 웹서비스에 관한 연구

이병권(ByongKwon Lee),김봉현(Bonghyun Kim) 한국컴퓨터정보학회 2024 한국컴퓨터정보학회 학술발표논문집 Vol.32 No.1

개별기업 주식의 거래량과 주가 간의 인과관계 검증: 한국주식시장을 중심으로

류형선 ( Hyungseon Ryu ),양성국 ( Sungkuk Yang ),김봉현 ( Bonghyun Kim ) 아시아.유럽미래학회 2013 유라시아연구 Vol.10 No.1

Stock price is affected by various elements: economic factors such as the domestic or global economic trend, non-economic factors like labor dispute or war, and internal factors in company including change of major shareholders, development of new product, M&A, or capital increase with consideration. In this sense, stock price is a final result reflecting all the political, economic, and social context which is associated with the company. The relation between trading volume and stock return has been long discussed by the scholars and the financial professionals. Many researches have been tried to figure out the systematic and universal relation between those two in theoretical aspect, but it has never reached any consensus. The preceding empirical studies on the relation have shown the different conclusion depending on the sample period or the sample market. The study on the trading volume is the most active and animated field of research among the precedent studies on the determinant of stock prices. That is because trading volume and stock prices are one of the easiest information for the investors to access, and it also means that trading volume are usually assumed as an influential factor to affect the stock price or to get affected by the stock price. Trading volume helps to predict the future flow of the stock price in advance, but it also grants credibility for the flow. If the amount of trade increases and the price also increases, then it could be quite surely presumed that the price is going to rise constantly. However, if the price goes up but the trading volume goes down, then it never be accepted that the stock price will continuously rise. Rather, in most cases, the stock price stops to rise, and falls. Likewise, it is a widely accepted that trading volume is interrelated with the fluctuation in stock price. Many researchers has tried to account the relationship between trading volume and stock price from theoretical perspective in various ways, and this long concern has focused on how to gain a distinguished performance with the interest in market efficiency and the use of trading volume information. However, though there is no unanimous conclusion which accounts the relationship, most investors take it as a generalized fact that trading volume causes a change in price in such cases as trading volume increases when stock price increases, and trading volume decreases when stock price decreases. Thus, this study has a purpose on analyzing the relationship between stock prices and trading volume which are widely used as information for investment. In other words, it is for figuring out whether the trading volume has an effect on the stock price, or vice versa. Therefore, the study aims to find out the effect of the investment strategy using the trading volume information when investing the individual companies. In this paper, analysis period was taken from the daily data of 10 years which is 2,482 days from 2nd January, 2002 to 29th December, 2011 from KOSPI, and also from the daily data of 6 years which is 1,489 days from 2nd January, 2006 to 29th December, 2011 from KOSDAQ. As an analysis method, unit root test was used to distinguish whether the time series data is normal or not, and Granger Causality test also was applied to look at the causal relationship between trading volume and stock prices. The differences of this study from the precedent ones are as in this following. First, the analysis in this paper includes the top five types of market capitalization in the KOSPI market and KOSDAQ market during the sample period so as to figure out the causal relationship between trading volume and stock prices. Second, the study uses average daily trading volume which is mainly used in the preceding studies as well as 5-day, 20-day, 60-day, and 120-day average trading volume. Those various sorts of trading volumes are for finding out which type is the most suitable information to account for the reality. The results from the study are as follows. First, the stock price often has a significant effect on the trading volume, especially when it comes to average daily trading volume, 5-day and 60-day average trading volume. It is as same consequence as the previous studies. Second, the trading volume also often has a considerable effect on the stock prices. It was observed especially in average daily trading volume, 5-day and 60-day average trading volume. It is slightly different result, comparing with the preceding studies that the stock prices affects the trading volume. Third, 5-day average trading volume exerts more substantial influence on the stock prices than any other sorts of trading volumes. In particular case of Daum Communications Corp., 5-day average trading volume has a noticeable influence on the stock prices. Fourth, those significant relations are usually observed in KOSDAQ market more than in KOSPI. It means that the more successful performances are expected in KOSDAQ market when the investment strategy is established using the trading volume information.

질소화합물 처리 효율 향상을 위해 개발된 미생물을 이용한 수처리공법 적용에 관한 연구

박배성(Baesung Park),이재민(Jaemin Lee),최병욱(Byeongwook Choi),황상연(Sangyeon Hwang),이정준(Jungjun Lee),김봉현(Bonghyun Kim),김진동(Jindong Kim),연승준(Seungjun Yeon),김정민(Jungmin Kim),허희승(Heeseung Heo),최진영(Jinyoung Choi) 대한환경공학회 2022 대한환경공학회 학술발표논문집 Vol.2022 No.11