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Research on functional area-specific technologies application of future C4I system for efficient battlefield visualization (미래 지휘통제체계의 효율적 전장 가시화를 위한 기능 영역별 첨단기술 적용방안)

  • Sangjun Park;Jungho Kang;Yongjoon Lee;Jeewon Kim
    • Convergence Security Journal
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    • v.23 no.4
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    • pp.109-119
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    • 2023
  • C4I system is an integrated battlefield information system that automates the five elements of command, control, communications, computers, and information to efficiently manage the battlefield. C4I systems play an important role in collecting and analyzing enemy positions, situations, and operational results to ensure that all services have the same picture in real time and optimize command decisions and mission orders. However, the current C4I has limitations whenever a new weapon system is introduced, as it only provides battlefield visualization in a single area focusing on the battlefield situation for each military service. In a future battlefield that expands not only to land, sea, and air domains but also to cyber and space domains, improved command and control decisions will be possible if organic data from various weapon systems is gathered to quickly visualize the battlefield situation desired by the user. In this study, the visualization technology applicable to the future C4I system is divided into map area, situation map area, and display area. The technological implementation of this future C4I system is based on various data and communication means such as 5G networks, and is expected to enable hyper-connected battlefield visualization that utilizes a variety of high-quality information to enable realistic and efficient battlefield situation awareness.

Proposals to Revise the Occupational Exposure Limits for Aluminum in Korea (국내 크롬 및 그 화합물의 노출실태 및 노출기준 개정 제안)

  • Seung Won Kim;Young Gyu Phee;Yong-Joon Baek;Taejin Chung;Jeong-Hee Han
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.34 no.2
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    • pp.166-178
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    • 2024
  • Objectives: The 12 occupational exposure limits(OELs) for chromium and its compounds in Korea were set by applying the American Conference of Governmental Industrial Hygienists (ACGIH) Threshold Limit Values (TLVs). However, this is significantly different from the TLVs after the existing TLVs were integrated and withdrawn in 2018, so it is necessary to review the revision. Methods: Various documents related to chromium OELs were reviewed, including the ACGIH TLV Documentations for chromium and its compounds. A field survey was conducted targeting workplaces handling chromium and its compounds. Based on this, a revised OELs were proposed and a socio-economic evaluation was conducted. Results: The OELs for chromium compounds in Korea was first enacted in 2002, and in 2007, the OELs for chromium (hexavalent) compounds (insoluble) was lowered from 0.05 mg/m3 to 0.01 mg/m3. In 2008, the OELs for strontium chromate was newly established as 0.0005 mg/m3, and in 2018, the OELs for calcium chromate was newly established as 0.001 mg/m3. Total chromium and hexavalent chromium were measured for each of 6 samples at 2 welding sites, 4 plating sites, and 2 spray coating sites. When omparing the average of the results measured by ICP, a total chromium analysis method, and the analysis results by IC, a hexavalent chromium analysis method, only workplace 4 was the same, and total chromium was evaluated more, and total chromium was evaluated at 0.0004 to 0.0027 mg/m3. And hexavalent chromium was evaluated as non-detection ~ 0.0014 mg/m3. Amendment ①: The exposure standard for hexavalent chromium is not divided into water soluble, insoluble, chromium ore processing, and other hexavalent chromium compounds, and is integrated into 0.01 mg/m3, which is the level of chromium (hexavalent) compound (insoluble)., OELs for chromium (metal) and chromium (trivalent) compounds are integrated into chromium (trivalent) compounds, and the exposure level is maintained. Amendment ②: As in the amendment ①, the OELs are integrated, but the level is lowered to 0.005 mg/m3, which is the OELs of OSHA, and there is a grace period of 4 years. Amendment ③: As in the amendment ①, the OELs are integrated, but the level is lowered to 0.0002 mg/m3, which is the exposure standard of ACGIH, and there is a grace period of 5 years. Conclusions: Amendment ①: The change in the OELs is insignificant, so the cost required is small, and the benefit/cost ratio is greater than 1, so there is no problem in applying the amendment. Amendment ②: In all scenarios except chromium 6(insoluble), the benefit/cost ratio is greater than 1, so it is thought that there will be no major problem in applying the amendment. Amendment ③: Since the benefit/cost ratio is less than 1 in all scenarios, it is thought that the total social benefit that can be obtained when applying the amendment is not large.

First Record of the Invasive Alien Mollusk Melanoides tuberculata (Müller, 1774) (Gastropoda, Thiaridae) in South Korea (침입성 외래연체동물 서양다슬기(Melanoides tuberculata)에 대한 국내 최초 기록)

  • Youngjun Park;Soon Jae Eum;Youngho Cho;Yonglak Jeon;Yungchul Jun;InChul Hwang;Soon Jik Kwon
    • Korean Journal of Ecology and Environment
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    • v.57 no.3
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    • pp.162-168
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    • 2024
  • The purpose of this study was to record for the first time in Korea the presence of Melanoides tuberculata (an invasive alien species), which was confirmed during the "National Survey on the Status of Alien Species" in Jukdang stream (also known as Guppy Stream, located in Icheon, Gyeonggi Province), which is affected by the year-round discharge of heated effluent from a large semiconductor factory and where various tropical organisms, including ornamental fish, appear due to artificial release. A Total of 52 specimens were collected, and they can be visually distinguished from native melanian snails by their reddish-brown flames and spots. Genetic analysis further confirmed the species as Melanoides tuberculate. Melanoides tuberculata typically inhabits tropical climates, but its presence has been confirmed in altered aquatic environments such as Jukdang stream, where the water temperature remains warm even in a temperate climate. This indicates the need for further monitoring of domestic streams with similar conditions, particularly those receiving heated effluent, like Jukdang stream. Additionally, due to its strong reproductive capacity, including parthenogenesis, and its adaptability to various environments, there have been cases where the populations of Pomacea lineata and Aylacostoma tenuilabris have declined. This suggests that Melanoides tuberculata may have a competitive advantage in interspecific competition, potentially suppressing native species populations if it spreads within the domestic ecosystem. Melanoides tuberculata serves as an intermediate host for parasites that can cause diseases in both humans and animals, raising public health concerns in many countries. There is also a significant risk that it could be mistaken for native melanian snail species and consumed, which necessitates a high level of caution.

The Study on well-aging using digital fitness technology (디지털피트니스 기술을 활용한 웰에이징에 관한 연구)

  • Seungae Kang
    • Convergence Security Journal
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    • v.24 no.3
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    • pp.231-237
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    • 2024
  • The rapid aging of the global population poses significant challenges to public health systems, as it often correlates with various physical, cognitive, and social declines among the elderly. Traditional approaches to promoting healthy aging emphasize the importance of physical activity, mental engagement, and social connectivity. However, factors such as mobility issues and resource constraints can limit the accessibility and effectiveness of these approaches. Digital fitness technologies, including wearable devices, mobile applications, virtual reality platforms, and AI-based feedback systems, present innovative solutions with the potential to enhance the physical, cognitive, and social well-being of older adults. This study analyzes the latest trends in digital fitness technologies and proposes strategies for effective utilization in promoting well-aging. Specifically, it addresses the need for improved technology accessibility through affordable devices and user-friendly interfaces, the development of personalized fitness programs, strategies to enhance ongoing participation such as social interaction and gamification, and solutions for data protection and ethical issues. Effective implementation of these strategies is expected to significantly improve the health and well-being of older adults. Future research and policy development should incorporate these elements to maximize the impact of digital fitness technologies and enhance the overall quality of life for the elderly.

Antibacterial and Therapeutic Effects of Houttuynia cordata Ethanol extract for Murine Salmonellosis (어성초 ethanol 추출물의 마우스 살모넬라 감염증에 대한 항균 및 치료효과 규명)

  • Kim, Dong-Hyeok;Lim, Jung-Ju;Lee, Jin-Ju;Jung, Won-Chul;Shin, Hyeon-Jin;Lee, Hu-Jang;Kim, Gon-Sup;Kim, Suk
    • Korean Journal of Environmental Agriculture
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    • v.27 no.2
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    • pp.156-162
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    • 2008
  • Salmonellosis is a major bacterial zoonosis that causes a variety of disease syndromes, self-limited enteritis to fatal infection in animals and food-borne infection and typhoid fever in humans. Recently, the emergence of multidrug resistant strains of Salmonella spp. causes more serious problems in environment and public health. The present study was investigated the antibacterial effect of Houttuynia cordata ethanol extract(HCEE) for murine salmonellosis. In the cytotoxic effect of HCEE on RAW 264.7 cells, there was no detectable effect with any concentrations between 25 and 100 ${\mu}g/ml$ after 8 h incubation. The bacteriocidal effect of HCEE was not showed on a Salmonella enterica serovar Typhimurium(S. typhimurium). HCEE makes morphological change of the RAW 264.7 cells, and there was significant decreased bacterial uptake and intracellular replication within Salmonella infected cells. And further nitric oxide(NO) production of Salmonella infected RAW 264.7 cells with HCEE was decreased comparing to RAW 264.7 cells without HCEE until 8 h post infection. Oral administration of HCEE showed a therapeutic effect for S. typhimurium infected BALB/c mice. The mortality of HCEE treated mouse was 80% until 12 days, while that of HCEE untreated mouse was 100 % until 8 days after lethal dose of S. typhimurium infection. These data suggested that HCEE has a potency treatment for intracellular replicative pathogen including salmonellosis, brucellosis, tuberculosis, listeriosis etc., and the application of HCEE makes new strategies for safety medicine development without antibiotic resistance bacterial appearance and residue problem in food and solves the public health problem from antibiotic mis- and over use.

Microbiological Hazard Analysis for HACCP System Application to Vinegared Pickle Radishes (식초절임 무의 HACCP 시스템 적용을 위한 미생물학적 위해 분석)

  • Kwon, Sang-Chul
    • Journal of Food Hygiene and Safety
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    • v.28 no.1
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    • pp.69-74
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    • 2013
  • This study has been performed for 150 days from February 1 - June 31, 2012 aiming at analyzing biologically hazardous factors in order to develop HACCP system for the vinegared pickle radishes. A process chart was prepared as shown on Fig. 1 by referring to manufacturing process of manufacturer of general vinegared pickle radishes regarding process of raw agricultural products of vinegared pickle radishes, used water, warehousing of additives and packing material, storage, careful selection, washing, peeling off, cutting, sorting out, stuffing (filling), internal packing, metal detection, external packing, storage and consignment (delivery). As a result of measuring Coliform group, Staphylococcus aureus, Salmonella spp., Bacillus cereus, Listeria Monocytogenes, E. coli O157:H7, Clostridium perfringens, Yeast and Mold before and after washing raw radishes, Bacillus cereus was $5.00{\times}10$ CFU/g before washing but it was not detected after washing and Yeast and Mold was $3.80{\times}10^2$ CFU/g before washing but it was reduced to 10 CFU/g after washing and other pathogenic bacteria was not detected. As a result of testing microorganism variation depending on pH (2-5) of seasoning fluid (condiment), pH 3-4 was determined as pH of seasoning fluid as all the bacteria was not detected in pH3-4. As a result of testing air-borne bacteria (number of general bacteria, colon bacillus, fungus) depending on each workplace, number of microorganism of internal packing room, seasoning fluid processing room, washing room and storage room was detected to be 10 CFU/Plate, 2 CFU/Plate, 60 CFU/Plate and 20 CFU/Plate, respectively. As a result of testing palm condition of workers, as number of general bacteria and colon bacillus was represented to be high as 346 $CFU/Cm^2$ and 23 $CFU/Cm^2$, respectively, an education and training for individual sanitation control was considered to be required. As a result of inspecting surface pollution level of manufacturing facility and devices, colon bacillus was not detected in all the specimen but general bacteria was most dominantly detected in PP Packing machine and Siuping machine (PE Bulk) as $4.2{\times}10^3CFU/Cm^2$, $2.6{\times}10^3CFU/Cm^2$, respectively. As a result of analyzing above hazardous factors, processing process of seasoning fluid where pathogenic bacteria may be prevented, reduced or removed is required to be controlled by CCP-B (Biological) and threshold level (critical control point) was set at pH 3-4. Therefore, it is considered that thorough HACCP control plan including control criteria (point) of seasoning fluid processing process, countermeasures in case of its deviation, its verification method, education/training and record control would be required.

Study on the Silicone Contact Lens Using AA and BMA (AA(Acrylic acid)와 BMA(Butyl methacrylate)를 이용한 실리콘 콘택트렌즈에 관한 연구)

  • Kim, Tae-Hun;Yae, Ki-Hun;Kweon, Young-Seok;Sung, A-Young
    • Journal of Korean Ophthalmic Optics Society
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    • v.11 no.3
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    • pp.259-265
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    • 2006
  • We polymerized material of AA(Acrylic acid) and BMA(butyl methacrylate) to make up for the weak points of hydrogel contact lens. The synthesis process of silicone synthesis is as follows. Acrylate-PDMS(Polydimethylsiloxane)-Urethane prepolymer was composed after Diisocynate reacted with HEMA(2-hydroxyethylmethacrylate) under the catalyst and it reacted again with bis(hydroxyalkyl) terminated poly(dimethylsiloxane) with high oxygen transmissibility characteristics. HEMA(2-hydroxyethylmethacrylate) was used to make prepolymer that can be polymerized and the urethane was used to improve elasticity and oxygen transmissibility, copolymerization was performed with conventional hydrogel contact lens materials to make silicone hydrogel contact lens with higher oxygen transmissibility. For manufacturing of contact lens, We added BMA(Butyl methacrylate) with better elasticity and flexibility, and AA(Acrylic acid) with higher moisturizing to used contact lens materials. AIBN (Azobis2-methylpropionitrile) as initiator and EGDMA(Ethylene Glycol Dimethacrylat) as crosslinking agent were used and the lens with higher oxygen transmissibility and better moisturizing were manufactured complying with basic contact lens properties, which have several combination trial of each monomer characteristics. Compounding SN which included SILICONE, HEMA, NVP and EGDMA etc was showed by swelling ratio of 9.38% and water content of 23.7%. SN was showed by swelling ratio of 9.38%, water content of 23.7% and a visible ray transmissibility of 89%. SB which added BMA in the SN was showed by swelling ratio of 12.50%, water content of 18.56% and a visible ray transmissibility of 88%. SAB which added both AA and BMA in the SN was showed by swelling ratio of 8.33%, water content of 12.93% and a visible ray transmissibility of 88%.

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Characteristics of Breeding Birds Community in Relation to the Forest Environment in Deogyusan National Park (덕유산국립공원의 산림환경에 따른 번식기 조류군집 특성)

  • Yu, Jae-Pyoung;Jin, Seon-Deok;Kim, Hyoun-Sook;Lee, Joon-Woo;Paek, Woon-Kee;Song, Ho-Kyung
    • Korean Journal of Environment and Ecology
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    • v.25 no.2
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    • pp.132-144
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    • 2011
  • We studied the forest environment and characteristics of bird community between April and September of 2010 on the Hyangjeokbong area(A), Baekryunsa area(B) and Anseong area(C), all in the Deogyusan National Park. Hyangjeokbong area of the high latitude ridge was characterized by the Taxus cuspidata and Abies koreana etc., and deciduous broadleaf forest species, such as the Quercus mongolica, with abundance of subalpine zone coniferous trees, the Hemerocallis fulva and the Rhododendron schlippenbachii, while the areas Baekryunsa and Anseong were primarily characterized by deciduous broadleaf forests, with the valleys showing Fraxinus mandshurica colonies. In terms of the DBH(diameter at breast height) of trees, between 11 and 20cm showed the highest frequencies, while over 30cm was the highest in Baekryunsa area and the lowest in Hyangjeokbong area. Furthermore, in terms of coverage in relation to layers, in Hyangjeokbong area, the coverage volume of the lower layer was very high, in Baekryunsa area, the coverage volume of the middle layer between 8 and 12m was the highest, and in Anseong area, the coverage volume of the upper layer over 18m was the highest. A total of 53 bird species were observed during the study period at the Deogyusan National Park. The numbers of species and density of areas were 25 species and 45.20 Ind./km for Hyangjeokbong area, 50 species and 58.63 Ind./km for Baekryunsa area and 35 species and 66.89 Ind./km for Anseong area, with Baekryunsa area showing the highest number of species and Anseong area showing the highest level of density. In terms of dominant species, in Hyangjeokbong area, Cettia diphone, along with species which inhabit in grassland and shrubs, were the dominant species, and species which live in the canopy layer, including the Aegithalos caudatus, were found to be dominant in Baekryunsa and Anseong areas. For guild structure, bush nesting guild and bush foraging guild species were the highest in all areas, and the hole nesting guild and the air foraging guild species showed the lowest proportion. This seems to be the result of the low number of trees with diameter at breast height of over 30cm, which results in the lack of nesting grounds for hole nesting guild species.

Fish Safety and Antimicrobial Activity of Natural Sulfur Solution on Aquatic Microorganisms (Saprolegnia parasitica) Isolated from Misgurnus mizolepis (미꾸라지(Misgurnus mizolepis)에서 분리된 수생균 (Saprolegnia parasitica)에 대한 천연유황수의 항균 활성 및 처리에 대한 어류 안전성)

  • Yi, Seung-Won;Lee, Seung-Hyeop;Lee, Sang-Jong;Kim, Mi-Hee;Lee, Hye-Hyun;Chu, Saet-Byul;Kim, Kyung-Hee;Lee, Hee Jung
    • Korean Journal of Environmental Biology
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    • v.35 no.2
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    • pp.116-122
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    • 2017
  • Basic dyes such as malachite green and methylene blue have been used as disinfectants to control water fungal infections since the 1930s. However, after succeeding reports of carcinogenicity and bioaccumulation of the dye, their use was forbidden in lieu of public health. This study undertook to evaluate the therapeutic effect of sulfur solution processed by effective microorganisms (EM-PSS) against Saprolegnia parasitica infection, and its safety in fish. In vitro antifungal evaluation of EM-PSS inhibited the growth of S. parasitica mycelia at concentrations of 50 ppm or higher. The acute toxicity test of EM-PSS to the mud fish (Misgurnus mizolepis) measured a no effect concentration (NOEC) at 100 ppm, the lowest effect concentration (LOEC) at 125 ppm, and the half-lethal concentration ($LC_{50}$) at 125 ppm in juvenile and 250 ppm in the immature stage. In addition, the ecotoxicity test of EM-PSS using Daphnia magna inhibited swimming of D. magna at concentrations of 100 ppm or less. Lastly, the EM-PSS prevented infection of S. parasitica to mud fish, at concentrations of 50 ppm. Furthermore, at 100 ppm concentration, the EM-PSS showed no acute toxicity on mud fish, nor any eco-toxic effects on D. magnano. Therefore, we conclude that carcinogenic disinfectants such as malachite green and methylene blue could be replaced by EM-PSS to remove S. parasitica in mud fish farming, and might be a potential eco-friendly disinfectant in aquaculture.

A Study of the Real Conditions of the Management of Dental Hygienists' Self-Oral Health (치과위생사의 자기구강건강관리에 관한 연구)

  • Lee, Kyung-Ae
    • Journal of dental hygiene science
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    • v.5 no.2
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    • pp.45-49
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    • 2005
  • This study is designed to present basic materials necessary for offering the more effective way of dental hygienists, or those who are in charge of the education of Oral health, the treatment and prevention of dental problems, educating Oral health by stage by dint of determining the actual condition of the knowledge and management of dental hygiene, or prevention of the basic dental disease except the professional methods of dental management and evaluating their abilities to manage dental hygienes. In terms of the real conditions of the management of dental hygienes, the majority of the subjects said, "not bad" or "healthy". Most of them (62.1%) said that they brush their teeth three times a day, and most of them (85.2%) depend on rolling methods. 69.2% of them used brushes that are neither hard nor soft, and 28.4% of them use soft brushes and 49.7% of them brush their teeth for about 3 minutes. In terms of brushing time, 27.8% of them brush their teeth after lunch, while 23.8% of them brush their teeth after breakfast. 66.3% of them use fluoric tooth pastes while 19.5 percent of them said, "I have no idea." and 14.2% of them said, "No." In terms of complementary dental hygiene goods, dental goggles are used by 23% of them, and dental threads are used by 78.1% and tooth brushes are used by 78.1% of them, and 42.4% of the subjects use the instruments one to twice a day, and 53.8% of them use them for less than one minute a time. In terms of dental health care, 17.2% of them have a chew of gum and 8.3% of them pay a regular visit to dental clinics and 5.3% of them don't smoke.

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