• Journal of Korean Institute of Industrial Engineers
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• v.13 no.1
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• pp.11-24
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• 1987

Automatic Guided Vehicle Systems feature battery powered driverless vehicles with programming capabilities for path selection and positoning. Vehicles serve the machines in shop, following a guide path system installed on the shop floor. The basic problem in the system is to determine a fixed set of vehicle routes of minimal total distance(time) while keeping capacity and distance(time) constraints. In this paper, a heuristic algorithm is presented for scheduling the automatic guided vehicles. The algorithm routes the machines based on their distances and polor coordinate angles, taking into account the structural feature of the system. Computational experiments are performed on several test problems in order to evaluate the proposed algorithm. Finally, a framework for dealing with the case where supplies from the machines are probabilistic is described.

• The Journal of Korea Robotics Society
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• v.17 no.4
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• pp.493-499
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• 2022

This paper presents the design for the kinematic structure of a system for an automatically moored 6000 ton autonomous ship in a port, and the process and results of optimal design for the link cross-sectional shape. We propose an automatic mooring system with a PPP type serial manipulator structure capable of linear motion in the XYZ axis. The mooring force applied by the mooring system was derived with dynamics simulation tool "ADAMS". The design goal is the minimization of the cross-sectional area of the link. Constrains include compressive stress and shear stress. The optimization problems were solved by using the sequential quadratic programing method implemented in the fmincon package. The shape of the cross section was assumed to be rectangle. Through future research, we plan to manufacture automatic mooring system for 6000ton class autonomous ship.

• Journal of Practical Engineering Education
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• v.15 no.1
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• pp.193-198
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• 2023

This paper analyzed the validity of exercise problems for each unit in Python programming education. Practice questions presented for each unit are presented through an online learning system, and each student uploads an answer code and is automatically graded. Data such as students' mid-term exam scores, final exam scores, and practice questions scores for each unit are collected through Python lecture that lasts for one semester. Through the collected data, it is possible to improve the exercise problems for each unit by analyzing the validity of the automatic scoring exercise problems. In this paper, Orange machine learning tool was used to analyze the validity of automatic scoring exercises. The data collected in the Python subject are analyzed and compared comprehensively by total, top, and bottom groups. From the prediction accuracy of the machine learning model that predicts the student's final grade from the Python unit-by-unit practice problem scores, the validity of the automatic scoring exercises for each unit was analyzed.

• Journal of Navigation and Port Research
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• v.30 no.9
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• pp.773-777
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• 2006

Significant increase of container flows in the marine terminals requires more efficient port equipments such as logistic and transfer systems. This paper presents collision avoidance and routing approach based on dynamic programming (DP) algorithm for a linear motor based shuttle car which is considered as a new transfer system in the port terminals. Most of routing problems are focused on automatic guided vehicle (AGV) systems, but its solutions are hardly utilized for LM based shuttle cars since both are mechanically different. Our proposed DP is implemented for real-time searching of an optimal path for each shuttle car in the Agile port terminal located at California in USA.

• 제어로봇시스템학회:학술대회논문집
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• 2004.08a
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• pp.1870-1873
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• 2004

The objective of this study is to investigate the possibility of chemical process synthesis purely based on mathematical programming when given an objective, feed conditions, product specifications, and model equations for available process units. A method based on a state space approach is proposed, and applied to an example problem with a reactor, a heat exchanger, and a separator. The results indicate that a computer can automatically synthesize an optimal process without any heuristics or expertise in process design provided that global optimization techniques are improved to be suitable for large problems.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.397-402
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• 2005

In this paper, to improve the efficiency of welding and user convenience in the shipbuilding industry, a PC-based off-line programming (OLP) technique and the development of a robot transfer unit are presented. The developed OLP system is capable of not only robot motion simulations but also automatic generations of a series of robot programs. The strength of the developed OLP system lies in its flexibility in handling the changes of the welding robot's target objects. Moreover, for a precise transfer of the robot to a desired location, an auxiliary mobile platform named a robot-origin-transfer-unit (ROTU) was developed. To enhance the cornering capability of the platform in a narrow area, the developed ROTU is equipped with 2 steering wheels and 1 driving wheel. Both the OLP and the ROTU were field-tested and their performances were proven successful.

• Proceedings of the Korean Information Science Society Conference
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• 2011.06c
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• pp.466-469
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• 2011

단계가 없는 고차원 프로그램(higher-order program)을 다단계 프로그램(multi-staged program)으로 타입의 도움을 받아 변환하는 방법을 제시한다. 이 방법은 최첨단의 다단계 프로그램 타입시스템에 기반했기에 직관적으로 이해가 쉽고, 열린 코드(open code)를 지원한다. 변환의 결과 나올 수 있는 열린 코드는 자유 변수(free variable)을 허용하여 나중에 사용자의 의도대로 자유롭게 묶이게 할 수 있다. 우리의 변환은 기존의 타입의 도움을 받아 특화시키는 Linger와 Sheard[2,3]의 방법에 비해 더 효율적이고, 더 많은 종류의 다단계 프로그램을 만들어 낼 수 있다.

• International Journal of Computer Science & Network Security
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• v.21 no.4
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• pp.131-139
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• 2021

In current time, anomaly detection is the primary concern of the administrative authorities. Suspicious activity identification is shifting from a human operator to a machine-assisted monitoring in order to assist the human operator and react to an unexpected incident quickly. These automatic surveillance systems face many challenges due to the intrinsic complex characteristics of video sequences and foreground human motion patterns. In this paper, we propose a novel approach to detect anomalous human activity using a hybrid approach of statistical model and Genetic Programming. The feature-set of local motion patterns is generated by a statistical model from the video data in an unsupervised way. This features set is inserted to an enhanced Genetic Programming based classifier to classify normal and abnormal patterns. The experiments are performed using publicly available benchmark datasets under different real-life scenarios. Results show that the proposed methodology is capable to detect and locate the anomalous activity in the real time. The accuracy of the proposed scheme exceeds those of the existing state of the art in term of anomalous activity detection.

• The Journal of Economics, Marketing and Management
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• v.4 no.1
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• pp.1-8
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• 2016

The purpose of this paper is to discuss the methodology of optimizing delivery route scheduling using a capacity integer linear programming problem model developed to a previous case study. The methodology suggests a two-stage decision: the first, automatic, where the manager will obtain guidance generated by the solution of the linear programming model, later they could use post-optimization techniques to fine tune to the best operational solution. This study has the goal to reduce the size of service companies' ground transportation fleets, aiming not only to reduce costs and increase competitive advantages but also to lower levels of air pollution and its consequences, traffic and, therefore, the levels of carbon dioxide, allowing for a reduction in envir onmental disasters.

• Journal of Internet Computing and Services
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• v.8 no.6
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• pp.75-85
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• 2007

One of important factors for improving the learning achievement of students in computer programming education is to provide plenty of opportunities of problem-solving experiences through variety forms of assignments, However, for the most cases, evaluation of programming assignments is performed manually by instructors and automated tools for the accurate evaluation are not equipped at the present time. Under this restricted environment instructors need much work and time to grade assignments so that instructors could not deliver sufficient programming assignments to students, In order to overcome this problem. au automated programming assignment evaluation system is needed that would enable instructors to evaluate assignments easily in an effective and consistent way and also to detect any plagiarism activities among students in program source codes readily, Accordingly, in this paper we design and implement a Web-based programming assignment grading system that allows instructors to evaluate program performance automatically as well as to evaluate program styles and piagiarism easily with appropriate feedback.