• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.39 no.12
• /
• pp.1237-1244
• /
• 2015

A gerotor can be manufactured in a miniature size because it has a high discharge per cycle and a simple structure. Gerotors are widely used for the lubrication oil of an engine and as the hydraulic source of an automatic transmission. Recently, improvements in fuel efficiency and noise reduction have come to the fore in the automobile industry, and it has been necessary for better fuel efficiency to continuously improve the flow rate and noise of internal gear pumps through the optimal design of the gerotor and port shape. In this study, gerotors were generated based on the equations derived for a lobe shape with multiple profiles (ellipse 1-elliptical involute-ellipse 2). The ranges of the design parameters were considered to prevent a cusp and loop. In addition, the optimal lobe shape was obtained by determining the influence of the lobe shape on the performances (flow rate, irregularity, etc.), according to the values of the design parameters.

• The Journal of the Korea Contents Association
• /
• v.9 no.12
• /
• pp.1-9
• /
• 2009

A doll created by various materials is a miniature based on human model, and it has been one of components in a puppet show to take some responsibility for human's culture activity. However, demand and supply keeps on the decrease in the puppet show industry, since professional puppeteer has been reduced rapidly, and also it is difficult to initiate into the skill. Therefore, many studies related Robotic Marionette for automation of puppet show have been internationally accompanied, and more efficient structure design and process development are required for better movement and express of puppet with motor based controller. In this research, we suggest the effective way to enable to express the marionette's motion using motion data based on motion capture and 3D graphic program, and through applying of 3D motion data and proposal of simulation process, it will be useful to save time and expenses when the Robotic Marionette System is practically built.

• International Commerce and Information Review
• /
• v.14 no.3
• /
• pp.209-227
• /
• 2012

Northeast Asia where is an epicenter of the global financial crisis's conquest is traditional imbalanced region of oil production and consumption. In recent years, the region has been suffered by the shortage of oil storage and transportation facilities due to surging oil trading and necessity in strategic reserves. Therefore, since independent petroleum logistics with the storage facilities and oil trading hub is required to form efficient oil market in this region. In this study, we analyzed the efficiency of refinery facilities by country that is of importance in being a logistics hub in Northeast Asia by employing non-static and dynamic efficiency analysis, which are a part of DEA(Data Envelopment Analysis) and then policy implications have been drawn. The result illustrates Korea's is the highest country in terms of efficiency of oil refining facilities in Northeast Asia. It implies that Korea has strong position to be the oil hub in Northeast Asia.

• Journal of Environmental Impact Assessment
• /
• v.12 no.3
• /
• pp.199-209
• /
• 2003

The withdrawal method for protecting the uncontaminated part from the spread of contaminants was suggested by a simultaneous equation. The formulation of them is based upon the build up of the ridge part between the contaminated and uncontaminated parts that resulted from the efficient use of barrier wells. The quality in the withdrawn groundwater depends upon the heads at wells no. 5 and 6. The determination of pumping rates and qualities with changing the heads at wells no. 5 and 6 should be given by considering the demand for water use and the capacity and cost for removing the contained contaminants. The results of this study should be used in taking a plan for supplying water use as well as preventing the spread of contaminants from some known contaminated sources.

• Proceedings of the Korean Society of Broadcast Engineers Conference
• /
• 2017.06a
• /
• pp.14-17
• /
• 2017

인터넷의 발달과 스마트 디바이스의 등장은 기존의 쇼핑구조 및 쇼핑방식에 큰 변화를 가지고 왔으며, 소비자의 일상생활에도 주목할 만한 질적 성장과 발전을 이루게 하였다. 특히, 쇼핑구조는 소매점에서 대형 쇼핑몰로 오프라인 구매에서 인터넷과 스마트 디바이스를 통한 온라인 구매로 변화하고 있고, 쇼핑방식도 오프라인 매장에서 인터넷, 모바일 등 복수 채널을 종합해 고객경험 관리를 최대화하기 위한 옴니 채널의 형태로 급격하게 변하고 있다. 그러나 기존의 옴니 채널은, 고객의 상품 구매 경험을 극대화 시키는 데 중점을 두었기 때문에, 고객 입장에서 보면 채널별 제품정보(가격, 환불정책, 배송정보, 공급점포의 위치 등)의 부족 및 일관성이 결여되어 있어 최종 구매결정까지는 시간이 걸리고, 구매한 제품에 대한 만족도가 낮아서 반품 비율이 상당히 높은 것이 현실이다. 마찬가지로, 유통업체 입장에서 보면 제품의 유효기간, 재고 관리 등 유통과정에 있어서의 제품정보의 일관성이 결여되어 있어, 완전하고 정확한 최신 제품정보의 제공을 통한 소비자의 구매 유도에 큰 어려움을 겪고 있다. 본 논문은 멀티미디어(영상 및 음성) 식별기술을 이용하여, 기존(고객중심)의 옴니 채널이 가지고 있는 문제점을 해결하여, 소비자 및 유통업체에게 구매 및 관리에 충분하고 일관성이 있는 "제품정보 중심의 옴니 채널" 유통모델 및 구현에 관한 방법을 설명한다.

• Proceedings of the Korea Water Resources Association Conference
• /
• 2006.05a
• /
• pp.1098-1101
• /
• 2006

최근 3대강특별법에 의하여 시행되고 있는 환경부의 수질오염총량관리를 위해 서낙동강 유역인 낙본N 단위유역에 대한 해당 지자체의 기본계획과 시행계획이 수립된 바 있다. 낙본N 단위유역은 서낙동강을 중심으로 좌측의 대부분이 경상남도 김해시이고, 우측과 하류부는 부산광역시 강서구이다. 서낙동강은 평상시에는 주요 농업용수 공급원과 철새도래지로서 홍수시에는 거대한 유수지 역할을 하고 있다. 서낙동강 유역내에는 분뇨처리장, 하수처리장, 농업 및 축산활동, 내수면 양식어업, 오염원 배출공장 등의 점, 비점오염원이 있으며 대저수문과 녹산수문에 의해 조절되는 정체수역으로서 오염부하강도가 높은 유입지천들로 인하여 상습적인 녹조 발생수역으로 수질개선의 필요성이 매우 높은 지역이다. 본 연구에서는 대표 유역으로 낙본N유역의 소유역 중 배출부하량이 가장 큰 지류에 해당하는 조만강 유역인 낙본N06 소유역의 오염원 조사결과를 이용하여 오염부하량 산정기법을 검토하였다. 장래 오염부하량 예측은 자연증가, 개발계획, 삭감계획에 의해 산정하는데, 이와 같은 과정에서 과거 오염원조사, 부하량산정, 폐수 배출부하량 모니터링 과정에서의 불확실성이 따르게 된다. 본 연구에서는 이와 같은 오염부하량산정 과정에서의 정확도를 높이고자 오염원 자료의 증감에 따른 오염부하량 산정결과의 민감도 분석을 통하여 신뢰도 평가를 수행하였다. 방대한 오염원자료를 이용한 오염부하량 산정은 한국환경정책평가연구원(KEI)에서 개발한 데이터베이스관리 프로그램(Access Program)을 이용하였으며, 각 오염원별 오염원 현황 및 전망 결과와 환경부의 수계오염총량관리기술지침에서 제시한 각 오염원별 오.폐수발생원단위, 배출원단위, 전환계수, 배출계수 등을 이용하여 각 오염원별 배출부하량을 산정하였다. 본 연구에서는 오염원 조사나 장래 오염원 예측에서 있을 수 있는 오차에 대한 전체 배출부하량의 변화를 살펴봄으로써 방대한 양의 오염원 조사시에 정확성 및 효율성을 높이고자 하였다. 본 연구의 결과를 통해 할당부하량을 개별 오염원별로 할당하고 적정한 개발계획과 실현가능한 삭감계획 및 이행방안을 수립하기 위한 오염원조사를 수행함에 있어 기초자료의 효율적인 관리를 통해 오염부하량 산정의 정확성을 높이고자 한다.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.38 no.1
• /
• pp.80-86
• /
• 2010

This paper describes the development result of S-band Transmitter of STSAT-3 by satellite research center(SaTReC), KAIST. STSAT-3 has two kinds of communication channels, S- band for Telemetry & Command and X-band for mission payload. S-band Transmiiter(STX) consist of modulator, frequency synthesizer, power amp and DC/DC converter. The modulation scheme of STX is FSK(Frequency Shift Keying). The interface between spacecraft OBC and STX is RS-422. The STX is based on modular design. The RF output power of STX is 1.5W(31.7dBm) and BER of STX is under 1E-5. The Test of STX is completed successfully such as functional Test and environmental(vibration, thermal vacuum) Test.

• The Korean Journal of Pesticide Science
• /
• v.4 no.4
• /
• pp.31-34
• /
• 2000

The contents of hexachlorobenzene (HCB), a hazardous impurity, in chlorothalonil were monitored through 1996 to 2000. The number of samples were 32 from three different sources. The contents determined by GLC/ECD were ranged from 0.0036% to 0.0330% with average content of 0.0219%. All the samples were recorded below 0.05%, which is the regulation standard of HCB in the technical. The total input of HCB in Korean agriculture was calculated to be approximately 77 kg a year.

• Journal of the Korean Society of Propulsion Engineers
• /
• v.19 no.1
• /
• pp.76-86
• /
• 2015

KSLV-II, a new launch vehicle of Korea, requires a new launch complex(LC) for its own and proper launch operations. The new launch complex will be constructed in NARO Space Center neighboring KSLV-I launch complex for maximizing operation efficiency and economic matters. The launch complex consists of three ground support equipments, i.e., mechanical, electrical, and fuel in general. The fuel ground support equipment could be defined as a combination of systems for storage and supply of propellants and gases which are required by a launch vehicle. The compositions, functions and capabilities of fuel ground support equipment are introduced in this paper. In addition, basic design results of flame deflector configurations are included.

• Journal of the Institute of Electronics and Information Engineers
• /
• v.50 no.7
• /
• pp.149-156
• /
• 2013

This paper presents a hardware edge detector of image signal at pixel level of CMOS image sensor (CIS). The circuit detects edges of an image based on a bump circuit combining with the pixels. The APS converts light into electrical signals and the bump circuit compares the brightness between the target pixel and its neighbor pixels. Each column on CIS 64 by 64 pixels array shares a comparator. The comparator decides a peak level of the target pixel comparing with a reference voltage. The proposed edge detector is implemented using 0.18um CMOS technology. The circuit shows higher fill factor 34% and power dissipation by 0.9uW per pixel at 1.8V supply.