• Title/Summary/Keyword: DTA

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Estimation of the Sound Radiation Efficiency of the Hull Considering the Type and Natural Frequency of Plates of It (선체 구성 강판의 종류 및 고유진동수를 고려한 선체의 음향방사효율 추정)

  • Han, HyungSuk;Lee, KyungHyun;Park, SungHo
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.23 no.12
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    • pp.1073-1081
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    • 2013
  • The definition of the radiation efficiency is very important to estimated underwater radiated noise of a ship. Considering the structure of the ship, it can be found that the hull of a ship consists of a lot of plates supporting by longitudinal and transverse stiffener. Therefore, various modes of the hull vibration occur related to the combination of these plates including stiffeners. In this paper, the method to define the radiation efficiency is suggested considering the vibration mode of the hull based on Uchida's experimental equation of the radiation efficiency. The suggested method is verified by the experiments with various kinds of naval vessels.

Development of a CDMA Field Engineering System (CDMA 필드 엔지니어링 시스템 개발)

  • Lee, Chan-Su;Im, Hui-Gyeong;Hong, Seong-Cheol;Im, Jae-Bong;Seong, Yeong-Rak;O, Ha-Ryeong
    • The Transactions of the Korea Information Processing Society
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    • v.7 no.5
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    • pp.1500-1510
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    • 2000
  • In this paper, a CDMA (Code Division Multiple Access) field engineering system is designed and implemented for managing cellular telecommunication base stations. For high quality of CDMA service, optimized cell planning is crucial. For such cell planning, base stations must be managed based on analysis of CDMA field dta. The proposed system consists of two modules: a measurement module and au analysis of CDMA field dta. eh proposed system consists of tow modules; a measurement module and an analysis module. The measurement module collects various CDMA field dta and displays them on a vector map in a real-time manner. The analysis module associates measured data with various related information, e.g. base station information, and process them statistically. The proposed system can drastically reduce base station management cost.

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Estimation of Uncertainty in Vibration Measurement of Shipboard Equipment (함정탑재장비 진동 측정불확도 추정)

  • Park, Sungho;Lee, KyungHyun;Han, HyungSuk
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.24 no.7
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    • pp.509-516
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    • 2014
  • This paper proposes estimation model of uncertainty in vibration measurement of shipboard equipment and analyzes the result of uncertainty estimation. Vibration of shipboard equipments affects underwater radiated noise that is important performance related to stealth of the naval vessel. Acceptance testing for shipboard equipment is required to guarantee the stealth performance of naval vessel. In measuring, detailed uncertainty estimation is essential to improve measuring reliability. Acceptance testing result of structure-borne noise and vibration is used to analyze uncertainty in vibration measurement of shipboard equipment.

A Study on Process Control Modeling for Precision Guided Munitions Quality Control (정밀유도무기 품질관리를 위한 공정관리 수행모델에 관한 연구)

  • Kim, Si-Ok;Lee, Chang-Woo;Cha, Sung-Hee
    • Journal of Korean Society for Quality Management
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    • v.41 no.3
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    • pp.487-494
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    • 2013
  • Purpose: In this study, we propose the precision guided munitions verification methodology using the statistical analysis method has been proposed. and it can be applied to the precision guided munitions quality assurance work. Methods: This modeling is based on Failure Mode and Effects Analysis, Statistical Process Control, Defense Quality Managerment System, Production Readiness Review, Manufacturing Readiness Assesment and so on. Results: The Process Control Modeling that has the following procedures ; searching the critical to quality, statistical analysis by process, verify process. Moreover, the effectiveness of the methodology is verified by applying to the precision guided munitions. Conclusion: To achieve a analysis methods of statistical process control and verify process for precision guided munitions.

High Occurrence Conditions of Hollow Heart and Internal Brown Spot in Potatoes (Solanum tuberosum L.) (내부갈색반점(內部褐色斑點)과 내부공동(內部空洞) 저항성(抵抗性) 감자 계통 선발을 위한 다발성(多發生) 조건 구명(究明))

  • Lim, Hak-Tae;Khu, Dong-Man;Chun, Ik-Jo;Yang, Sung-Ji
    • Horticultural Science & Technology
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    • v.19 no.4
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    • pp.455-458
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    • 2001
  • To screen potato clones with high resistance to hollow heart (HH) and internal brown spot (IBS), field conditions were set up to induce high frequencies of physiological disorders in 'Atlantic' potato through various treatments of mulching, periodic shadings, and plant growth regulators such as trinexapac-ethyl (Tr-E) and dicloprop-triethanol mine (DTA). IBS occurrence was as high as 67.5% in the field plot mulched with transparent film and shaded for 10 days beginning at 80 days after planting. The highest level of HH was 22.9% in the plot mulched with transparent film and shaded for 10 days beginning at 60 days after planting. Very high level of IBS (66.3%) also occurred in the plot treated with 1500 mg/L of Tr-E 40 days after planting, while HH occurred by 21.3% in the plot treated with 1000 mg/L of DTA 70 days after planting. In the plots which were treated with 1,500 mg/L of Tr-E after 40 days of planting and 1000 mg/L of DTA after 70 days of planting, 'Superior' (moderately highly resistant) and 'Atlantic' (very susceptible) could be clearly distinguished to be resistant and susceptible. High occurrence condition set up in this study could be applied for the potato breeding program to screen potato clones with high resistance to HH and IBS.

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Evaluation of Results in Pesticide Residues on Incongruity Commercial Agricultural Commodities using Network Analysis Method (네트워크 분석을 활용한 유통농산물 잔류농약 부적합 현황 분석)

  • Park, Jae Woo;Seo, Jun Ho;Lee, Dong Hun;Na, Kang In;Cho, Sung Yong;Bae, Man Jae
    • Journal of Food Hygiene and Safety
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    • v.33 no.1
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    • pp.23-30
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    • 2018
  • The purpose of this research was to introduce network analysis method for analyzing pesticide residues in incongruity commercial agricultural commodities. Based on the "results in pesticide residues on incongruity commercial agricultural commodities" on "Guidelines for food safety management 2017", we used centrality analysis for pesticide residues via degree, closeness and betweenness centrality measurement. In case of degree centrality result, chlorpyrifos and diazinon were the most highly "connected node" in pesticide network. For the closeness centrality result, the most pesticides showed the similar closeness trend except for 19 species of pesticides. Fludioxonil and chlorpyrifos are recognized as the "bridge" of pesticides network with their high betweenness centrality. The results of network analysis show the "relation" data, which could not represent through out the conventional statistical analysis, among the pesticide residues. We hope that the network analysis method will be appropriate and precise tool for analyzing pesticide residues via elaboration and optimization.

A Study on the Evaluation for Performance of Body Armor Vest using ANOVA (분산분석을 이용한 방탄조끼의 방탄성능 평가에 관한 연구)

  • Park, Jae Woo;Byun, Kisik;Cho, Sung-Yong;Kim, Suk Ki;Yeo, Yongheon;Kwon, Jae Wook
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.22 no.1
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    • pp.372-378
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    • 2021
  • A body armor vest is a form of munition related directly to the safety and life of combatants. Therefore, it must meet the requirements for ballistic resistance. The ROK demands the performance of body armor vest meet the Level IIIA specified by the NIJ STD-0101.06 published by the US National Institute of Justice. This study performed acceptance tests on body armor vests. The factors for evaluating the ballistic resistance evaluated were not only whether it penetrates when shooting but also whether the BFS (Backface Signature) depth does not exceed 44 mm when it does not penetrate. The factors were assessed to determine if they were consistent or not. The BFS depth is affected by various test factors, such as the physical properties of the backing material and the changes in the amount of impact with the bullet velocity. In this study, an analysis of the bulletproof performance was performed by extracting the data with the same conditions using ANOVA to remove the influence of these external factors. The analysis revealed a correlation between the BFS depth, bullet velocity, vest conditions, and protection area. The mass production process was analyzed by estimating the Interval of BFS on each lot. Through this, a new methodology for ballistic resistance evaluation and paradigm for future quality assurance is suggested.

석탄회를 이용한 요오드화세슘의 포집특성 분석

  • 박장진;신진명;전관식;김연구;박현수
    • Proceedings of the Korean Nuclear Society Conference
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    • 1996.05c
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    • pp.403-408
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    • 1996
  • 석탄화력발전소 폐기물인 석탄회와 요오드화 세슘의 반응특성을 DTA(Differential Thermal Analysis), TGA(Thermo-Gravimetric Analysis) 장치를 이용하여 분석하였다. 본연구에 사용된 석탄회는 85%의 실리카와 알루미나를 함유하고 있으며 Si/Al 몰비는 2.1 이었다. DTA와 TGA의 열분석 결과 CsI의 분해, 석탄회와 기체상 세슘의 반응 등으로 이루어져 있다. 석탄회와 CsI의 혼합물은 94$0^{\circ}C$ 이상에서 Pollucite 가 형성되었다. 반응생성물들의 SEM 분석결과 표면이 거칠며 bulky한 crystal 형태로서 구형의 석탄회와는 매우 다른 형상을 보였다. 석탄회는 요오드화세슘의 고정화를 위해서 적합한 알루미노규산염 원료물질들 중의 하나임을 확인하였다.

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스마트폰의 기술동향 및 군적용 방안

  • Jeon, Su-Yong;Park, Yeong-Su
    • Information and Communications Magazine
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    • v.28 no.4
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    • pp.28-34
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    • 2011
  • 스마트폰은 최근 일반 대중에 빠르게 확산되며 정보이용과 소통방식의 변화를 견인하고 있다. 이러한 변화에 발맞추어 정보화된 미래전장에서 스마트폰의 국방분야 적용 방안에 대한 관심이 증폭되고 있다. 본고에서는 스마트폰의 기술동향 및 해외 국방분야 스마트폰 사용 사례에 대해 살펴보고 이를 바탕으로 스마트폰을 국방분야에 적용할 경우 고려할 점과 군용 스마트폰 개발 방안을 제시하고자한다.

Dissolution and Transformation of Crystal Forms of Piroxicam (피록시캄 결정형의 용출과 형전환)

  • Son, Yeong-Taek
    • YAKHAK HOEJI
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    • v.40 no.5
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    • pp.513-521
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    • 1996
  • The polymorphism of piroxicam was studied. Form I, II, III and monohydrate designated as Form IX were prepared by recrystallization from different solvents. Depending on the coo ling rate of the piroxicam melt, Form IV, V, VI, VII and VIII were prepared. The crystal forms were characterized by DTA, TGA and UV spectroscopy. Their dissolution patterns were also investigated. During storage at ambient condition. Form VIII was transformed into Form I and it was accelerated by milling. The other crystal forms were also transformed into Form I by milling. Form I and Form IX were very stable.

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