• The Journal of Korea Robotics Society
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• v.18 no.3
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• pp.299-307
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• 2023

In the midst of accelerating wars around the world, unmanned robot technology that can guarantee the safety of human life is emerging. ERP-42 is a modular platform that can be used according to the application. In the field of defense, it can be used for transporting supplies, reconnaissance and surveillance, and medical evacuation in conflict areas. Due to the nature of the military environment, atypical environments are predominant, and in such environments, the platform's path followability is an important part of mission performance. This paper focuses on reducing the minimum turning radius in terms of improving path followability. The minimum turning radius of the existing 2WS/2WD in-wheel platform was reduced by increasing the torque of the independent driving in-wheel motor on the rear wheel to generate oversteer. To determine the degree of oversteer, two GPS were attached to the center of the front and rear wheelbases and measured. A closed-loop speed control method was used to maintain a constant rotational speed of each wheel despite changes in load or torque.

• Nuclear Engineering and Technology
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• v.56 no.3
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• pp.1116-1123
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• 2024

-In recent years, unmanned underwater vehicles (UUV) have been vigorously developed, and with the continuous deepening of marine exploration, traditional energy can no longer meet the energy supply. Nuclear energy can achieve a huge and sustainable energy supply. The heat pipe reactor has no flow system and related auxiliary systems, and the supporting mechanical moving parts are greatly reduced, the noise is relatively small, and the system is simpler and more reliable. It is more favorable for the control of unmanned systems. The use of heat pipe reactors in unmanned underwater vehicles can meet the needs for highly compact, long-life, unmanned, highly reliable, ultra-quiet power supplies. In this paper, a heat pipe reactor scheme named UPR-S that can be applied to unmanned underwater vehicles is designed. The reactor core can provide 1 MW of thermal power, and it can operate at full power for 5 years. UPR-S has negative reactive feedback, it has inherent safety. The temperature and stress of the reactor are within the limits of the material, and the core safety can still be guaranteed when the two heat pipes are failed.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.6
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• pp.70-77
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• 2020

Configuration management is an important project management method. Configuration management is increasing daily and improving defense power as a management tool for technical data of power support systems. Configuration management work must be carried out properly from the beginning of development to acquire an excellent weapon system. In procurement, configuration management is a vital factor that can determine the cost of maintaining operations during the transfer of military supplies and carry out systematic management among operational support. Countries are making changes to policies and systems to manage R&D, standards, and patents in conjunction with each other from the beginning of research and execution, and it is important to establish the concept of managing and controlling the configuration as an efficient means of managing military resources. To identify the activity details during the entire life cycle from the beginning of acquisition to the end of disposal by linking munitions configuration control with the total life cycle, and redefine the appropriate work system, this study investigated and analyzed the U.S. configuration control procedures to identify the activity details and present areas to develop.

• Journal of the Korea Organic Resources Recycling Association
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• v.20 no.3
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• pp.60-70
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• 2012

Zn, Cu, Fe, Al contents of sludges produced from sewage treatment plants and night soil treatment plant in Pocheon City, Gyeong-gi Province were investigated. And the accumulated contents of those metals in the earthworm Eisenia fetida were also investigated while 15, 30, 45, 60, 75, 90, 105 grams(dw) of sludges were cumulatively supplied to the earthworms. Zn contents of sludges were 75.1~196.1 mg/kg, Cu contents 3.74~76.1 mg/kg, Fe contents 219.9~857.8 mg/kg, Al contents 198.4~991.7 mg/kg, all of which would not cause acute toxicity to the earthworm, but could cause sublethal effects on earthworm and reduce the density of next generation's population. However, cumulative supplies of sludges didn't increase the bioaccumulation rates of metals in the earthworm body, and BAFs of those metals after 60g of sludge supply were 0.0~0.43, which meant that the accumulated Zn, Cu, Fe, Al contents in the earthworm were lower than those of sludges.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.3
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• pp.994-1001
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• 2012

The Automotive seat is the component related at passenger feeling and safety. It absorbs the impact or vibration and supplies the comfortableness. It must also have sufficient rigidity and strength to satisfy these given conditions. Two kinds of seat models are designed and studied by structural analysis. Seat back frame (b) has lower deformation and fatigue life than (a). Most deformation and damage possibility is shown at the waist, that is the middle of model. On the vibration analysis at which natural frequency is applied, model (a) has the deformation from outside to inside of model, but model (b) has the deformation from inside to outside of model. Model (b) is safer than model (a) structurally at most cases.

• The Journal of Dong Guk Oriental Medicine
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• v.1
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• pp.1-13
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• 1992

Practical science means open and objective attitude as a new scholarly tone which gets out of Confucianism tradition and its closeness. It is concerned about practical aspect and its thought prevailed from the mid-16th century to the mid-19th century in feudal system. It is, also, the attitude seeking truth based on the facts, which is removed from the falsehood in politics, economics and social life. It is regarded as a social revolution which governs tile country economically and is utilized to stabilize and enrich a human living life. The new academic tradition appeared in the process of development of modernization proclaimed it to be utilized in modern-oriented independency. Modern historians have greatly studied the knowledge of early philosophy, while Korean oriental medicine has developed, basing on the cultivation of the mind, virtue, and benevolence through Han Bak-Keun(who showed much interest in realistic, economic and social system) and Jung Yak-Youg(who compiled all available data into one book). From Ko-Ryo dynasty to the mid-Yi dynasty Korean oriental medicine scholars struggled to develop oriental medicine in an attitude searching truth based on the facts. Among them Huh Jun's achievements and the content of his writings suggest any things with a view of practical science. These are neglected by most scholars so far, but I have surveyed as follows : 1) the revolution in oriental medical science system 2) the standardization of pharmacy appliance 3) the popularization of medicine supplies 4) cooperation of industry and academy in medical science field From the above I concluded as follows : practical science in Korean medical science began from Ko-Ryo dynasty and compiled in Ku Am Huh Jun in the period of King Sun-Jo of Li dynasty. With this repect, the pioneer in practical science in Korea is Ku Am Huh Jun. To search tile pioneer in practical science rightly we should study the history of Korean medical science.

• Molecules and Cells
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• v.37 no.2
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• pp.100-108
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• 2014

Salmonella enterica serovar Typhimurium (S. Typhimurium) is an intracellular pathogen that has evolved to survive in the phagosome of macrophages. The periplasmic copper-binding protein CueP was initially known to confer copper resistance to S. Typhimurium. Crystal structure and biochemical studies on CueP revealed a putative copper binding site surrounded by the conserved cysteine and histidine residues. A recent study reported that CueP supplies copper ions to periplasmic Cu,Zn-superoxide dismutase (SodCII) at a low copper concentration and thus enables the sustained SodCII activity in the periplasm. In this study, we investigated the role of CueP in copper resistance at a high copper concentration. We observed that the survival of a cueP-deleted strain of Salmonella in macrophage phagosome was significantly reduced. Subsequent biochemical experiments revealed that CueP specifically mediates the reduction of copper ion using electrons released during the formation of the disulfide bond. We observed that the copper ion-mediated Fenton reaction in the presence of hydrogen peroxide was blocked by CueP. This study provides insight into how CueP confers copper resistance to S. Typhimurium in copper-rich environments such as the phagosome of macrophages.

• Journal of Life Science
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• v.10 no.1
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• pp.14-21
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• 2000

The experiments were performed using both batch and continuous column reactors. Batch biodegradation studies were performed under aerobic conditions to determine the biodegradable fraction of the natural organic matter (NOM) source. NOM source was evaluated for its biodegradability at three different UV irradiation conditions and compared to its biodegradability without UV irradiation. In continuous experiments, system operating parameters of empty bed contact time (EBCT), recycle ratio, and influent concentration affected the extent of biofiltration in the biofilters. The effluent UV254/DOC ratios fro the biologically active columns were consistently lower than the influent values, which indicated that the dissolved organic carbon (DOC) removed by biodegradation was not a significant part of the UV-absorbable material. The increase in UV254/DOC ratio was caused by the DOC decrease across the biofilter because there was essentially no difference between the feed and effluent UV254 absorbance values over time. The results of this research showed that biofiltration was an effective method for removing the biodegradable fraction of NOM from water supplies.

• Journal of Digital Convergence
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• v.19 no.3
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• pp.363-369
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• 2021

This study improves the design of electric pot and cup that can safely pour and drink hot beverages among daily necessities for the blind and the elderly. It looks at the electric pot and cup that people with visual impairments usually use through their use perspective and studies and improves the safety problems that arise when using them based on the principle of universal design. Through this prior study, we study designs that can be used and shared by all disabled and socially disadvantaged people together and improve the design of household goods to expand the scope of use of general products and create new social values. In addition, through this design improvement process, everyone pursues an equal and virtuous life together, forms a well-off inclusive society, and takes advantage of the current position of the disabled and value of life once again.

• The Transactions of the Korean Institute of Power Electronics
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• v.27 no.5
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• pp.376-383
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• 2022

The improved performance of computer parts, such as graphic card, CPU, and main board, has led to the need for power supplies with a high power output. The dynamic load profile rapidly changes the usage of power consumption depending on load operations, such as PC power and air conditioner. Under dynamic load profile conditions, power consumption can be classified into maximum, normal, and standby power. Several problems arise in the case of maximum power. Peak power is generated at the system power source in the maximum-power situation. Frequent generation of peak power can cause high-frequency problems and reduce the life of high-pressure parts (especially high-pressure capacitors). For example, when a plurality of PCs are used, system overload occurs due to peak power generation and causes problems, such as power failure and increase in electricity bills due to exceeded contract power. To solve this problem, a system peak power limit/compensation power circuit is proposed for a power supply under dynamic load profile conditions. The proposed circuit detects the system current to determine the power situation of the load. When the system current is higher than the set level, the circuit recognizes that the system current generates peak power and compensates for the load power through a converter using a super capacitor as the power source. Thus, the peak power of loads with a dynamic load profile is limited and compensated for, and problems, such as high-frequency issues, are solved. In addition, the life of high-pressure parts is increased.