• 한국자동차공학회논문집
• /
• 제16권4호
• /
• pp.75-80
• /
• 2008

Biodiesel fuel(BDF) can be effectively used as an alternative fuel in diesel engine. However, BDF may affect the performance and exhaust emissions in diesel engine because it has different physical and chemical properties from diesel fuel such as viscosity, compressibility and so on. To investigate the effect of injection timing on the characteristics of performance and exhaust emissions with BDF in IDI diesel engine, it was applied the BDF derived from soybean oil in this study. The engine was operated at seven different injection timings from TDC to BTDC $12^{\circ}CA$ and six loads at a single engine speed of 1500rpm. When the fuel injection timing was retarded, better results were showed, which may confirm the advantages of BDF. The simultaneous reduction of smoke and NOx was achieved at some fixed fuel injection timings of an IDI diesel engine.

• 무역상무연구
• /
• 제16권
• /
• pp.117-154
• /
• 2001

The objective of the study is to propose to the strategy to make korean main ports to international logistics center in Northeast Asia. so this study's construction is constructed four steps. First, analysis the environment of economy, business and logistics industry in Northeast Asia. Second, analysis the constructions and characters of Free Zone Act. Third, analysis of Korean Government's policy about Free Zone. Forth, propose the growing strategy of Free Zone. In 1999 Northeast Asia was adopted in Korea, which will facilitate the process and strengthen the international logistics capability as a international logistics hub in Northeast Asia. But only adoption in the point of law is not enough to growing korean main seaport and airport to a international logistics hub. so various strategies are needed. In this study, we propose the growing strategies that are to establish and manage the free zone of ports and its hinterland are: the establishment of a long-term vision of international logistics complexes, the improvement of the proximity to markets/customers by way of linkage of global networks, the activation of the industrial complex in hinterland, the development of the skilled labor and the labor climate, the cooperation between governmental bodies and government/provincial bodies, continuous development of logistics infrastructure and so on.

• Journal of Multimedia Information System
• /
• 제6권4호
• /
• pp.225-234
• /
• 2019

Deep learning has become increasingly popular in both academic and industrial areas nowadays. Various domains including pattern recognition, Computer vision have witnessed the great power of deep neural networks. However, current studies on deep learning mainly focus on quality data sets with balanced class labels, while training on bad and imbalanced data set have been providing great challenges for classification tasks. We propose in this paper a method of data analysis-based data reduction techniques for selecting good and diversity data samples from a large dataset for a deep learning model. Furthermore, data sampling techniques could be applied to decrease the large size of raw data by retrieving its useful knowledge as representatives. Therefore, instead of dealing with large size of raw data, we can use some data reduction techniques to sample data without losing important information. We group PCB characters in classes and train deep learning on the ResNet56 v2 and SENet model in order to improve the classification performance of optical character recognition (OCR) character classifier.

• 한국정밀공학회:학술대회논문집
• /
• 한국정밀공학회 2001년도 춘계학술대회 논문집
• /
• pp.566-569
• /
• 2001

Hot Plate is the major unit that it used to remove damp of wafer surface, to strength adhesion of photoresist(PR) and to bake coated PR in FAB process of semiconductor. It is necessary to guarantee the performance of Hot Plate(HP). Therefore, in this study designed and developed the reliability system of HP to measure and estimated thermal uniformity and flatness in temperature setting amplitude $0~250^{\circ}C$. We developed the techniques that measures and analyzes thermal uniformity using infrared thermal vision, and compensates measuring error of flatness using laser displacement sensor. For measuring flatness, we specially makes the measurement stage of 3 axes which adopts the precision encoder. The allowable error of measuring technique is less than thermal uniformity, $\pm 0.1^{\circ}C$ and flatness, $\pm 1mm$. It is expected that the developed system can measure from $\Phi$210(wafer 8") to $\Phi$356(wafer 12") and also can be used in performance test of the Cool Plate and industrial heater, etc.

• International Journal of Fuzzy Logic and Intelligent Systems
• /
• 제6권2호
• /
• pp.161-166
• /
• 2006

Localization of mobile agent within a sensing network is a fundamental requirement for many applications, using networked navigating systems such as the sonar-sensing system or the visual-sensing system. To fully utilize the strengths of both the sonar and visual sensing systems, This paper describes a networked sensor-based navigation method in an indoor environment for an autonomous mobile robot which can navigate and avoid obstacle. In this method, the self-localization of the robot is done with a model-based vision system using networked sensors, and nonstop navigation is realized by a Kalman filter-based STSF(Space and Time Sensor Fusion) method. Stationary obstacles and moving obstacles are avoided with networked sensor data such as CCD camera and sonar ring. We will report on experiments in a hallway using the Pioneer-DX robot. In addition to that, the localization has inevitable uncertainties in the features and in the robot position estimation. Kalman filter scheme is used for the estimation of the mobile robot localization. And Extensive experiments with a robot and a sensor network confirm the validity of the approach.

• 대한전자공학회논문지
• /
• 제26권1호
• /
• pp.20-28
• /
• 1989

부분적으로 가려진 물체의 인식은 공장자동화를 위한 실제 문제를 해결하는 비젼 응용 분야에서 중요한 문제가 되고 있다. 본 논문에서는 부분적으로 가려진 2차원 물체의 인식 문제를 해결하는 한 기법에 대하여 서술한다. 이러한 기법은 3단계로 구성된다. 즉, 1) 경계점 추적, 2) 선형선소의 추출, 3) 정합확률에 의한 정합벡타의 결정으로 구성된다. 80개의 모델을 포함하고 있는 20개의 영상화면에서 시험해 본 결과는 평균적으로 95%의 인식율을 나타내었다.

• 수산해양교육연구
• /
• 제18권1호
• /
• pp.39-48
• /
• 2006

This study is supposed to grasp how The Entrepreneurship education(BizCool) that has been set as an example since April, 2002 has changed the Vocational high school students' perception of values or courses and then as the result of it, to get the early outcome of The Bizcool. The extent of the model schools mainly concentrated in the industrial and commercial department has to be spreaded to the students of various departments. In addition, diversification of the teaching material would be able to support the accomplishment of the suitable The Bizcool. The effectiveness of The Bizcool has been proven in various parts today, so its application is being magnified gradually. Also it is expected that many schools will adopt this program from now on. The Bizcool that has been executed to enhance the vision and self-confidence of the vocational high school students for their foundation, needs first of all, persistent support, investment and administration, and through these processes it will contribute to change the awareness about social unemployment problems and the vocational high schools.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• 제9권1호
• /
• pp.190-207
• /
• 2015

In the combustion engineering, to decrease pollution and increase production efficiency, and to optimally keep solid burning material amount constant in a burner online, it needs a smart method to detect the amount variation of the burning materials in a high temperature environment. This paper presents an online machine vision system for automatically measuring and detecting the burning material amount inside a burner or a boiler. In the camera-protecting box of the system, a sub-system for cooling is constructed by using the cooling water circulation techqique. In addition, the key and intelligent step in the system is to detect the pile profile of the variable burning material, and the algorithm for the pile profile tracing was studied based on the combination of the gey level (color) discontinuity and similarity based image segmentation methods, the discontinuity based sub-algorithm is made on the quaternion convolution, and the similarity based sub-algorithm is designed according to the region growing with multi-scale clustering. The results of the two sub-algoritms are fused to delineate the final pile profile, and the algorithm has been tested and applied in different industrial burners and boilers. The experiements show that the proposed algorithm works satisfactorily.

• 공학교육연구
• /
• 제23권4호
• /
• pp.3-13
• /
• 2020

The purpose of this study is to analyze the differences in the perception and education requirements between industry and engineering students on engineering convergence competency, and to suggest implications for fostering engineers suitable to industry demand and direction of focus improvement in the current engineering education field. To this end, 73 industrial representatives and 104 engineering students are surveyed the engineering convergence competency and educational needs. The results of this analysis are as follows: first, the difference in engineering convergence competency by background variable was significantly different in gender of engineering students. Second, it is found that there is a significant difference between the current level and the required level of engineering convergence competency from an industry perspective. In the IPA results, it shows that new knowledge generation and future-oriented vision skills are urgently needed to be improved. And it is showed that the creative thinking, knowledge utilization, communication, and cooperation capabilities skills need to be maintained continuously. Third, as a result of the analysis of the differences in recognition of the current competency levels between industry and engineering students, there is statistically significant differences in systemic thinking, communication and cooperation, understanding of other academic fields, humanities, and future-oriented perspectives. Therefore, it is necessary to specific plans and efforts to reduce this perception gap should be prepared at the university.

• 제어로봇시스템학회논문지
• /
• 제19권11호
• /
• pp.960-967
• /
• 2013

Shape recognition of solder ball bumps in a BGA (Ball Grid Array) is an important issue in flip chip bonding technology. In particular, the semiconductor industry has required faster and more accurate inspection of micron-size solder bumps in flip chip bonding as the density of balls has increased dramatically. The difficulty of this issue comes from specular reflection on the metal ball. Shape recognition of a metal ball is a very realproblem for computer vision systems. Specular reflection of the metal ball appears, disappears, or changes its image abruptly due to tiny movementson behalf of the viewer. This paper presents a practical shape recognition method for three dimensional (3-D) inspection of a BGA using a 5-step ring illumination device. When the ring light illuminates the balls, distinctive specularity images of the balls, which are referred to as "iso-slope contours" in this paper, are shown. By using a mathematical reflectance model, we can drive the 3-D shape information of the ball in aquantitative manner. The experimental results show the usefulness of the method for industrial application in terms of time and accuracy.