• Journal of the Korea Institute of Military Science and Technology
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• v.20 no.2
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• pp.264-271
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• 2017

Link-K message is the Tactical Data Link message standard developed by the Agency for Defense Development which is optimized for the Joint Operation of ROK Armed Force. KMTF message is the standard message format of Battle Management Information System. Interconversion and propagation between these messages are definitely needed to have efficient warfare such as situation data propagation using network, the convergence of collected situation data, common situational awareness, cooperative engagement. Therefore, this study suggests a way of rule and process for format conversion between Link-K and KMTF messages.

• Journal of Ecology and Environment
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• v.36 no.3
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• pp.193-204
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• 2013

Altitudinal patterns of plant species richness and the effects of area, the mid-domain effect, climatic variables, net primary productivity and latitude on observed richness patterns along the ridge of the Baekdudaegan Mountains, South Korea were studied. Data were collected from 1,100 plots along a 200 to 1,900 m altitudinal gradient on the ridge. A total of 802 plant species from 97 families and 342 genera were recorded. Common and rare species accounted for 91% and 9%, respectively, of the total plant species. The altitudinal patterns of species richness for total, common and rare plants showed distinctly hump-shaped patterns, although the absolute altitudes of the richness peaks varied somewhat among plant groups. The mid-domain effect was the most powerful explanatory variable for total and common species richness, whereas climatic variables were better predictors for rare plant richness. No effect of latitude on species richness was observed. Our study suggests that the mid-domain effect is a better predictor for wide-ranging species such as common species, whereas climatic variables are more important factors for range-restricted species such as rare species. The mechanisms underlying these richness patterns may reflect fundamental differences in the biology and ecology of different plant groups.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.49 no.3
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• pp.167-174
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• 2021

Computational Fluid Dynamics (CFD) was performed under low-speed wind tunnel test conditions using a 29.7% scale model of the NASA common research model. A wind tunnel test was conducted to measure the aerodynamic coefficient of the CRM with Belly sting model support configuration at a low Reynolds number of 0.3×106 and it was compared with the aerodynamic coefficient of CFD analysis. In order to verify the validation of the analysis, a computational analysis under the conditions of the advance research was performed and compared. The interference effect of the Belly sting model support affected not only the fuselage but also the main and tail wings.

• Journal of Korean Institute of Industrial Engineers
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• v.43 no.2
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• pp.120-126
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• 2017

This paper has proposed the development direction and R&D analysis approach that the diversity of defense R&D process and product should be mainly under consideration. It has shown that there is a fair possibility of the various quality assess to meet the R&D requirements in defense-based. Thus, the analysis on multiple quality elements is carried out with defense R&D characteristics. Especially, a quality management master planning based on the quality model of establishing defense R&D policy has proposed, identifying relevant quality characteristics on the R&D of weapon system and the R&D of core technology. That is, this paper is not only interested in determining an appropriate model for improving the quality of a R&D weapon system but also argued efforts in order to reap the best possible outcome and process on both the R&D of weapon system and quality of the R&D of core technology including present R&D activities.

• Korean Journal of Veterinary Research
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• v.60 no.1
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• pp.9-14
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• 2020

This study describes pathological, immunohistochemical, and bacteriological findings in adult dogs and fetuses naturally infected with Brucella (B.) canis. A total of 42 dogs including 40 dogs and 2 aborted fetuses were examined. The most common gross lesions in infected dogs were swelling of lymph nodes and spleen. The testes showed marked swelling with multifocal to diffuse reddish discoloration. The most significant histopathological lesions were observed in the placenta. Placental trophoblasts were markedly hypertrophied due to the accumulation of intra-cellular gram-negative bacteria. Lymphocytic inflammation of varying severity was observed in the reproductive organs such as male testis, epididymis, and prostate gland and female uterus. Strong immunolabelling was observed in the cytoplasm of most trophoblasts in the placental tissues using immunohistochemistry. However, immunohistochemical staining did not demonstrate any organisms in other organs of dogs and fetuses. B. canis isolates were most frequently obtained from the whole blood (82.5%) and superficial inguinal lymph node (77.5%) in both sexes. In addition, the isolation rate was higher in male genital organs than in those of females. Hence, management of male dogs is most important because infected dogs can play a role as carriers.

• Safety and Health at Work
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• v.4 no.4
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• pp.177-186
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• 2013

The use of nanoparticles (NPs) in industry is increasing, bringing with it a number of adverse health effects on workers. Like other chemical carcinogens, NPs can cause cancer via oxidative DNA damage. Of all the molecules vulnerable to oxidative modification by NPs, DNA has received the greatest attention, and biomarkers of exposure and effect are nearing validation. This review concentrates on studies published between 2000 and 2012 that attempted to detect oxidative DNA damage in humans, laboratory animals, and cell lines. It is important to review these studies to improve the current understanding of the oxidative DNA damage caused by NP exposure in the workplace. In addition to examining studies on oxidative damage, this review briefly describes NPs, giving some examples of their adverse effects, and reviews occupational exposure assessments and approaches to minimizing exposure (e.g., personal protective equipment and engineering controls such as fume hoods). Current recommendations to minimize exposure are largely based on common sense, analogy to ultrafine material toxicity, and general health and safety recommendations.

• Parasites, Hosts and Diseases
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• v.53 no.4
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• pp.501-506
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• 2015

Biting midges belonging to the genus Culicoides (Diptera: Ceratopogonidae) were collected by Mosquito $Magnet^{(R)}$ and black light traps at 5 sites on Jeju-do, Republic of Korea (Korea), from May-November 2013 to determine species diversity and seasonal distribution. A total of 4,267 specimens were collected, of which 99.9% were female. The most common species was Culicoides tainanus (91.8%), followed by C. lungchiensis (7.2%) and C. punctatus (0.6%), while the remaining 4 species accounted for <0.5% of all Culicoides spp. that were collected. High numbers of C. tainanus were collected in May, followed by decreasing numbers through August, and then increasing numbers through November when surveillance was terminated. Peak numbers of C. lungchiensis were collected during September, with low numbers collected from May-August and October-November. The presence of C. lungchiensis in Korea was confirmed by morphological and molecular analyses.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.29 no.10
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• pp.791-798
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• 2018

The CFAR algorithm is mainly used for target detection in radar systems. In particular, OS CFAR is used in a non-uniform noise environment. However, it requires a large amount of computation, because it should sort reference cells in ascending order. This makes it difficult to apply the radar system in real time. In this paper, we describe how to reduce the computational burden of OS CFAR. We compared the power of the test cell and reference cell to determine only the presence or absence of target detection. The common reference cells overlapping in the reference cells of the three test cells are obtained. We first compare the test cell with the highest power value among the three test cells to the common reference cells. Next, we compare each test cell to general reference cells, excluding the common reference cells. The computation time is shortened by reducing the power comparison computation amounts.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.17 no.3
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• pp.254-260
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• 2007

Trichloroethylene(TCE) is widely used as a degreasing solvent in workplaces. TCE is primarily toxic to the nervous system, however, systemic disorder like Stevens-Johnson syndrome has been recently reported in small-scale factories, where the government has had limited information of chemical use. A survey was performed to investigate the actual condition of using TCE and to provide practical information to occupational health service agencies and professionals. This survey was carried out on 103 factories out of 430 factories which were conducted periodic work environment measurement for TCE. Degreasing was the most popular reason for using TCE in Korea, which reached to 94%. TCE was also used as a solvent for rubber in the coating or molding process, and adhesives in the bonding process. Metal fabrication was the most common as 23%, followed by assembling automobile parts (17%), and machinery (12%). Workers exposed to TCE during full-shift were 52% while 48% were exposed during short period of the shift or intermittently. Manual or semi-automatic work occupied 87% while automatic work was just 13%. Though automatic work by a closed system was generally lower exposed to TCE, compared to manual work, it can cause a high exposure when the maintenance system is improper. Semi-automatic work especially like open-top degreasing process can cause a high exposure when local exhaust system with condensing and refrigerating coils in the degreaser does not work well. In conclusion, the survey showed nationwide status of TCE exposure in various aspects. It can be used to monitor workplaces and workers exposed to TCE to prevent occupational diseases.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.41 no.11
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• pp.1528-1538
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• 2016

Common data link systems are designed to transmit the imaginary and signal intelligence data at long distance air-ground line of sight(LOS) link. In this paper, we analyze the received power variation according to the communication distance of the common data link using curved earth 2-Ray model suitable for received signal power analysis of long distance air-ground wireless channel. We propose optimal elevation angle control method of the receiving antenna to reduce a power variation caused by ground-reflected wave. Proposed method can get additional link margin compared to the conventional method without any additional hardware performance enhancement.