• Journal of Sensor Science and Technology
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• v.9 no.3
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• pp.203-207
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• 2000

The sensitivity of ISFET glucose sensor is improved by employing amperometric actuation method. However, this method takes long time to recover the primary output voltage after measurement because of slow migration of the hydrogen ion between internal and external sensing membranes. Consequently, such a recovery-time delaying problem is one of obstacles to a practical use. In this paper, a new method is proposed to control the concentration of hydrogen ion in internal membrane, which applies a reduction potential to the working electrode for supplying hydroxide ion. Experimental results show that the recovery-time was reduced within 2 minute against decades minute of conventional method.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.36 no.5
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• pp.497-506
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• 2008

The purpose of this study was is leading landmark efforts to prevent the major causes of commercial-aviation fatalities about controlled flight into terrain(CFIT) in approach-and-landing accidents. The paper of major analysis for controlled flight into terrain(CFIT) was Guam accident, Mokpo accident and Gimhae accident in commercial transport-aircraft accidents from 1993 through 2002.CFIT occurs when an airworthy aircraft under the control of the flight crew is flown unintentionally into terrain, obstacles or water, usually with no prior awareness by the crew. This type of accident can occur during most phases of flight, but CFIT is more common during the approach-and-landing phase.The paper believed that prevention for CFIT accident was education and training for flying crew and upgrade for equipment such as EGPWS, and need more research for professional organizations of airlines.

• Fire Science and Engineering
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• v.32 no.2
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• pp.82-91
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• 2018

This study analyzed the working conditions and problems of screen fire shutters in the Goyang Bus Terminal fire based on the fire investigation results. At that time, screen fire shutters in the 1st basement, which was under construction, did not work because the power was shut off. Four screen fire shutters in the 1st and 3rd floor did not work despite the power not being shut off. The following problems related to a screen fire shutter were found: shutting off the power to screen fire shutters for the fire compartment on each floor, even when the fire compartments were changed in each area; installing an integral type screen fire shutter without any regulations, installing a two-stage screen fire shutter in a place not related to obstacles during evacuation; stopping the function of the screen fire shutters for a fire compartment on each floor after a combustible sandwich panel was comparted; installing a screen fire shutter over 10 meters in width, in which its performance was not verified; and no safety control standards for reinstalling or maintaining a screen fire shutter.

• Korean Journal of Weed Science
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• v.4 no.1
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• pp.96-106
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• 1984

Changes in weed floras and development of plant resistance to herbicides seemed to be closely related with increased and repeated use of herbicides. Herbicide use increased from 5% of the total consumption of pesticide in 1950 to 45% in 1976 in world basis. About 200 herbicides have been introduced to agriculture so as to control about 206 weed species which have been recorded important to human beings. In Korea, there was about 351 times in increased use of herbicides from 1966 to 1982. Interspecific selection by herbicide is mainly responsible for changes in weed floras and resulted in varying tolerance or susceptibility to herbicides, together with the changes of agricultural practices. The present trend toward continuous cereal cultivation throughout world will lead to type of changes in weed floras favorable to therophyte which can survive under unfavorable conditions as seeds rather than the types of geophyte which can survive unfavorable seasons as buds placed below soil surface. However, geophyte such as Sagitaria pygmaea, and Scirpus jurtcoides, and Cyperus rotundus and Cynodon dactylon in temperate warm climate become severe paddy weeds, presumably because of the removal of annual weeds by herbicides. Since differential tolerance to 2,4-D was firstly reported in Agrostis stolofera, about 30 species of weeds in 18 genera are presently known to have developed resistance to triazine herbicides. Resistance of weed biotypes to triazine herbicide is not mainly due to limited absorption and translocation or to the difference in metabolism, but is the result of biochemical changes at the site of metabolic activity, such as a loss of herbicide affinity for triazine binding site in the photosystem II complex of the chloroplast membrane. Genetical study showed that plastid resistance to triazine was wholly inherited through cytoplasmic DNA in the case of Brassica campestris. Plant tissue culture method can be utilized as an alternate mean of herbicide screening and development of resistance variants to herbicides as suggested by Chaleff and Parsons. In this purpose, one should be certain that the primary target process is operational in cell culture. Further, there are a variety of obstacles in doing this type of research, particularly development of resistance source and it's regeneration because cultured cells and whole plants represent different developmental state.

• Health Policy and Management
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• v.1 no.1
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• pp.3-18
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• 1991

On the stage of transition from highly centralized government to local self-government in Korea, administrating practice characteristics of the directors of Health Centers is essentially required to be found. This study was conducted in order to find the administration patte군 of the directors of Health Centers in Korea and their opinion on the environment of health administration including personnel management regime for them. The materials were collected from 149 directors of Health Centers with a structured questionaire by mailing. The major findings of this study were as follows. 1. About two-thirds of the directors(69.1%) make plan through the consensus between public service perosonnel in programme department and them in budgt control department. And 75.0% of the directors maintain the planed by the predecessor. 2. More than two-thirds of the directors (71.1%) take subordinates opinion into consideration in case of the programmes facing objections. 3. When the directors face obstacles in pursuing health programmes they usually consult other public service personnel than inhabitants. 4. Only 10.8% of the directors were satisfied with the support of the Ministry of Internal Affairs for health administration while more than half of them were satisfied with the support of health institution in higher level. 5. The directors evaluated the job attitude of the public service personnel in low level as more favorable than that of there higher level public service personnel who work for central government. 6. Only 18.1% of the idrectors were satisfied with their saley. And more than half of them expect the promotion of their position. On the ground of this result the administration attitude of the directors of Health Centers would be evaluated as improved and as more positive than that of other public service personnel in health authorities. However, they are required to consult the inhabitants more frequently for health administration. An the public service personnel in high level who work for central government are required to improve their job attitude.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.17 no.6
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• pp.130-137
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• 2003

Because of falling-off in power quality by harmonics, obstacles like lowering of capability, noise, vibration of power facilities and so on are occurred. Also generation of harmonics is inevitable and the point at harmonics is seriously gathering strength because energy saving installation using semiconductor circuit as countermeasures to enhance energy efficiency will be broadly spread and the use of energy conversion equipment like motor speed control contrivance, energy keeping installation and so on will increase, in the future. In order to eliminate harmonics obstacle, precision measurement and analysis on voltage, current, power factor, the each ingredient of harmonic order, the percentage of total harmonic distortion, and so forth are needed. In this paper, we developed low-cost measurement system to measure and analyze power quality connected with harmonics and verified it's performance by measuring and analyzing power quality in the three-phase and four-wire system.

• Journal of KIISE:Information Networking
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• v.31 no.6
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• pp.556-565
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• 2004

A Sandbox has been widely used to prevent damages caused by running of unknown malicious codes. It prevents damages by containing running environment of a program. There is a trade-off in using sandbox, between configurability and ease-of-use. MAPbox, an instance system of sandbox, had employed sandbox classification technique to satisfy both configurability and ease-of-use [1]. However, the configurability of MAPbox can be improved further. In this paper, we introduce a technique to attach dynamic class facility to MAPbox and implement MAPbox-advanced one. Newly generated class in our system has an access control with proper privileges. We show an example for improvements which denote our system have increased the configurability of MAPbox. It was determined as abnormal by MAPbox although is not. Our system could determine it as normal. We also show our techniques to overcome obstacles to implement the system.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.2
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• pp.696-702
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• 2010

In many industrial applications, it is very important to control the temperature of the controlled object to the target temperature as closely as possible. Although it is apparent that the great obstacles in controller design are time-delay of the thermal responses of the controlled object and the effect of thermal interference between neighboring heating zones, one more fundamental obstacle is a very large amount of time which is required during repeated experiments in controller design process. Therefore, a convenient simulation environment, which can represent thermal behavior accurately within appropriate time, is needed. In this paper, a prototype of 2D FEM (finite element method) heat transfer simulation environment using MATLAB is constructed to be usefully adopted into industrial applications with temperature controller design.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.13 no.11
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• pp.2349-2354
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• 2009

Due to growth of electronics and control devices, automation and situational awareness systems have been applied by automobile. Vision systems with the introduction of unmanned system being actively developed, but are still high price and visual information is passed through the cable, because of cars are difficult to install. In this paper, can be installed inside the car at low-cost, simple image processing device through a wireless communication know the obstacles and the alarm system based on Zigbee wireless communication, infrared and ultrasonic sensors to monitor the situation through with easy parking cars outside the system design was implemented.

• Industry Promotion Research
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• v.3 no.2
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• pp.87-94
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• 2018

This study suggests that lifelong education is regarded as a support system for lifelong learning, which includes all activities of educational characteristics, which ultimately has the goal of universalization of self - education. The goal is to successfully adapt to life. Statements supporting the need for lifelong learning have been found to be based primarily on the impossibility of this system to provide sufficient education to accelerate social change and to last a lifetime. The obstacles to implementation included inertia, resistance to change, motivation and cost. Opponents are likely to regard lifelong education as an attempt to expand compulsory education for exploitation and control purposes. This study found that there is an important consensus among supporters, but many questions remain. The full feasibility of lifelong education is considered to be far removed, and lifelong education should be interpreted as a source of direction and purpose, and ideals that society should aim for.