• Journal of Korea Society of Industrial Information Systems
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• v.5 no.4
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• pp.1-15
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• 2000

Information systems (IS) failures still continue and are prevalent everywhere. When considering an enormous amount of budget currently invested on IS technology in many organizations, these continuing failures can be critical culprits to failures of the organizations themselves. However, the meaning and definition of IS failures are not unified among IS researchers as well as IS practitioners although there have been a lot of conceptual research regarding the concept of IS failures. Previous empirical studies are not enough yet and thus we anticipate further empirical studies to be performed which will validate previous conceptual research. In this regards, by analyzing IS practitioners perception toward IS failures in a more detailed manner, this research extends conceptual and empirical research in the past which previously identified the structure of information systems (IS) failures. Further, this current study identified the interrelationships among the categories. The data was analyzed using a multidimensional scaling program and fourteen categories of problems were identified as to constitute the IS failure structure. It was found that about a half of categories identified were related to technical failures such as network and system infrastructure, costs, data/information, and program errors. The other remaining categories were related with organizational or social problems such as business success, human resources, relationships, communication, and user skills.

• Proceedings of the SAREK Conference
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• 2009.06a
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• pp.940-945
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• 2009

Energy planning for hybrid energy system is important to increase the flexibility in the urban community and national energy systems. Expected maximum loads, load profiles and yearly energy demands are important input parameters to plan for the technical and environmental optimal energy system for a planning area. The method for energy demand prediction has been based on artificial neural networks(ANN). The advantage of ANN with respect to the other method is their ability of modeling a multivariable problem given by the complex relationships between the variables. This method can produce 10% of errors hourly load profile from individual building to urban community. As the results of this paper, energy demand prediction system has been developed based on simulink.

• Korean Journal of Organic Agriculture
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• v.5 no.2
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• pp.13-36
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• 1997

This study aims to point out the basic strategy of agrotechnical and -political approaches toward successful settling for the environmental agriculture system in Korea. Although environmental agriculture & forestry strategy toward the 21st century and it's action program were released in 1996, some scientist from environmental agriculture and organic agriculture still argue on the errors of it's strategy and action program in terms of environmental sound functions. Especially it's strategy and action program of government did not focus the reduction of fertilizer and pesticide as the matters of weight and importance to reduction of fertilizer and pesticide as the matters of weight and importance to realize an environmental sound agriculture system. And korean organic agriculture gets a point in dispute, because 1) they do not practice of Basic Standard of IFOAM and FAO/WHO Codex draft, and 2) organic farming is defined quite differently from internationally recognized core aspects of organic agriculture. Organic farming, in Korea, is taken to mean the replacement of chemical fertilizer by organic manure and avoidance of agricultural chemicals. In the paper it is discussed the necessity, purpose, effect and consequence of basic standard for korean organic agriculture. The reformation of the certification system and t he direct payment system in environmental agriculture & forestry strategy toward the 21st century and it's action program by government, and on the need of the teaching program and curriculum in high education institution, the breeding program of resistant cultivars, the soil testing for optimum fertilization strategy, the nutrient management program, the declaration for 2020 environemntal agriculture are also discussed.

• Journal of Institute of Control, Robotics and Systems
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• v.16 no.10
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• pp.963-968
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• 2010

This paper handles ZMP based control that is inspired by neural networks for humanoid robot walking on varying sloped surfaces. Humanoid robots are currently one of the most exciting research topics in the field of robotics, and maintaining stability while they are standing, walking or moving is a key concern. To ensure a steady and smooth walking gait of such robots, a feedforward type of neural network architecture, trained by the back propagation algorithm is employed. The inputs and outputs of the neural network architecture are the ZMPx and ZMPy errors of the robot, and the x, y positions of the robot, respectively. The neural network developed allows the controller to generate the desired balance of the robot positions, resulting in a steady gait for the robot as it moves around on a flat floor, and when it is descending slope. In this paper, experiments of humanoid robot walking are carried out, in which the actual position data from a prototype robot are measured in real time situations, and fed into a neural network inspired controller designed for stable bipedal walking.

• Journal of Korean Institute of Industrial Engineers
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• v.31 no.3
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• pp.257-264
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• 2005

This paper suggests a heuristic algorithm for the clustering problem. Clustering involves grouping similar objects into a cluster. Clustering is used in a wide variety of fields including data mining, marketing, and biology. Until now there are a lot of approaches using Self-Organizing Feature Maps(SOFMs). But they have problems with a small output-layer nodes and initial weight. For example, one of them is a one-dimension map of k output-layer nodes, if they want to make k clusters. This approach has problems to classify elaboratively. This paper suggests one-dimensional output-layer nodes in SOFMs. The number of output-layer nodes is more than those of clusters intended to find and the order of output-layer nodes is ascending in the sum of the output-layer node's weight. We can find input data in SOFMs output node and classify input data in output nodes using Euclidean distance. We use the well known IRIS data as an experimental data. Unsupervised clustering of IRIS data typically results in 15 - 17 clustering error. However, the proposed algorithm has only six clustering errors.

• Fashion & Textile Research Journal
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• v.13 no.4
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• pp.624-634
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• 2011

The purpose of this study is to develop the pattern of safety clothes used at flat or mountainous areas and to identify the pattern of safety clothes by conducting experimental evaluation of virtual wear. Three subjects were selected, based on fire fighters' physical constitution. A prototype design for safety clothing was determined after in-depth interviewing of professionals and surveying of Forest service staff and related agency. Wearing test should be carried out in the order of pattern making, virtual and real wearing evaluation. For data analysis, technical statistical values should be obtained by using body measurements of subject, frequency analysis and T-test. The jacket is designed to have a front extension and the entire length of clothing enough for wearer to put on it over ordinary shirts or sweater. The collar of jacket is of round type. Cyber reality enables to identify the movement and activity of virtual fitting model and to find out errors or problems in safety clothing prior to on-the-spot wear test, thus raising the precision level of pattern. There was significant difference between real and virtual fit preference. The results show that the virtual try-on system need the development of a specific style.

• International Commerce and Information Review
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• v.7 no.3
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• pp.27-51
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• 2005

Todays, computers in business world are potent facilitators that most companies could not without them, while they are only tools. They offer extremely efficient means of communication, particularly when connected to Internet. What I stress in this article is the risks accompanied by e-commerce rather than the advantages of Internet or e-commerce. The management of e-commerce companies, therefore, should keep in mind that the benefit of e-commerce through the Internet are accompanied by enhanced and new risks, cyber risks or e-commerce risks. For example, companies are exposed to computer system breakdown and business interruption risks owing to traditional and physical risks such as theft and fire etc, computer programming errors and defect softwares and outsider's attack such as hacking and virus. E-commerce companies are also exposed to tort liabilities owing to defamation, the infringement of intellectual property such as copyright, trademark and patent right, negligent misrepresent and breach of confidential information or privacy infringement. In this article, I would like to suggest e-commerce insurance or cyber liability insurance as a means of risk management rather than some technical devices, because there is not technically perfect defence against cyber risks. But e-commerce insurance has some gaps between risks confronted by companies and coverage needed by them, because it is at most 6 or 7 years since it has been introduced to market. Nevertheless, in my opinion, e-commerce insurance has offered the most perfect defence against cyber risks to e-commerce companies up to now.

• Journal of Korean Neurosurgical Society
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• v.50 no.1
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• pp.23-29
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• 2011

Objective : The aim of the study is to determine the efficacy of indocyanine green (ICG) videoangiography for confirmation of vascular anastomosis patency in both extracranial-intracranial and intracranial-intracranial bypasses. Methods : Intraoperative ICG videoangiography was used as a surgical adjunct for 56 bypasses in 47 patients to assay the patency of intracranial vascular anastomosis. These patients underwent a bypass for cerebral ischemia in 31 instances and as an adjunct to intracranial aneurysm surgery in 25. After completion of the bypass, ICG was administered to assess the patency of the graft. The findings on ICG videoangiography were then compared to intraoperative and/or postoperative imaging. Results : ICG provided an excellent visualization of all cerebral arteries and grafts at the time of surgery. Four grafts were determined to be suboptimal and were revised at the time of surgery. Findings on ICG videoangiography correlated with intraoperative and/or postoperative imaging. Conclusion : ICG videoangiography is rapid, effective, and reliable in determining the intraoperative patency of bypass grafts. It provides intraoperative information allowing revision to reduce the incidence of technical errors that may lead to early graft thrombosis.

• Journal of Advanced Marine Engineering and Technology
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• v.38 no.5
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• pp.566-572
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• 2014

Recently, indoor navigation has been applied in large convention centers by using wireless sensor networks (WSNs), which provide not only a user's path to be traveled but also orientation and shopping information to increase user's convenience. This paper presents the localization system for estimating relative coordinates without pre-deployment of the reference node based on ultra wide band (UWB) ranging system, which is relatively suitable for indoor localization compared to other wireless communications, and azimuth sensor. The proposed localization system which consists of an azimuth sensor and a mobile node composed of three nodes estimates relative coordinates of the reference node without applying any recursive and time consumption algorithms. Also, in the process of estimating relative coordinates of the reference node, ranging errors are minimized through the proposed technique and the number of nodes can be reduced. Experimental results show the feasibility and validity of the proposed system.

• Proceedings of the KIPE Conference
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• 1998.10a
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• pp.774-779
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• 1998

For the speed control of motors, the position or speed sensors are necessary to obtain the position information of the rotor. Specially, SRM(Switched Reluctance Motor) needs an accurate rotor position data because both the rotor and the stator have a salient pole structure. High functional sensors like resolver or encoder are expensive and have complex connecting lines to the controller so the pure signals are apt to be mixed with noised. In the sight of SRM drives, the high temperature, heavy dust, and the EMI surroundings reduce the reliability of speed and position sensors. Therefore, the speed and position sensorless control algorithms using observer have been accepted widely. In this paper An adaptive sliding observer is described to control the SRM without speed or position sensors. The adaptive sliding observer is set on the basis of variable structure control theory. The sliding surface is constructed by current error terms and this surface guarantees the errors converge to "zero". The stability of observer is affirmed by Lyapunov stability analysis and popov's hyper stability theory.ty theory.