• Title/Summary/Keyword: small field

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AR based Field Training System Algorithm for Small Units (증강현실 기반의 소부대 야외 전술훈련체계 알고리즘)

  • Park, Sangjun;Kim, Jee Won;Kim, Kyoung Min;Kim, Hoedong
    • Convergence Security Journal
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    • v.18 no.4
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    • pp.81-87
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    • 2018
  • Military training is being carried out to win the combats through the quick and accurate response exercise for changeable engagement situations on battle fields. However, practically, it is really difficult to do actual fight training. Even though ROK Army is doing effort for practical training in KCTC(Korea army advanced Combat Training Center) supplying such as MILES equipments but a single platoon is able to use KCTC facilities or MILES equipments only 10 days a year. In order to find solution on this problem many researches suggesting AR or VR technology are still on the way. Nevertheless these are not fully covered the training done in the real field. In this regard, this paper proposes how the AR technology algorithm to apply on small units during field training exercise.

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A Study on Controlling Efflux Sediment Diffusion by Jetty Construction at Small Estuary (소규모 하구에서 토사유출 확산제어에 관한 연구)

  • Park, Sang Kil;Park, Hyun Su;Yoon, Jong Su;Lee, Si Ho
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.29 no.5B
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    • pp.483-491
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    • 2009
  • In this study, a jetty construction is taken into account for the reduction of sediment diffusive concentration incoming from the upstream river due to the urbanization and industrial development and to minimize the effects on the coastal ecosystems. The field observation and numerical calculation are conducted to analyze the diffusion zone of sediment concentration in the small estuary and coastal area. The specification of the installed jetty which is able to control the sediment concentration was decided based on the prediction of the dispersion area changes in space and time. The selected size and layout for the jetty design were examined for the dispersion zone by numerical calculation and field observation. As a result, the jetties constructed in the estuary retarded the dispersion rate of sediment concentration, so that the effect area of sediment dispersion was obviously decreased. In addition, the measured field data indicated that the sediment deposition in the inside of dikes could be controlled and the right side area of jetties could be preserved without influx sediment diffusion.

Image Feature Extraction Using Energy field Analysis (에너지장 해석을 통한 영상 특징량 추출 방법 개발)

  • 김면희;이태영;이상룡
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2002.10a
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    • pp.404-406
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    • 2002
  • In this paper, the method of image feature extraction is proposed. This method employ the energy field analysis, outlier removal algorithm and ring projection. Using this algorithm, we achieve rotation-translation-scale invariant feature extraction. The force field are exploited to automatically locate the extrema of a small number of potential energy wells and associated potential channels. The image feature is acquired from relationship of local extrema using the ring projection method.

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A study on the sheet drawing using the Matrix method (Matrix법을 이용한 판재 인발에 관한 연구)

  • 유홍균;전병희
    • Journal of the korean Society of Automotive Engineers
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    • v.13 no.6
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    • pp.90-100
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    • 1991
  • This paper represents the analysis of the sheet drawing by applying the Matrix method to Hill's slip-line field for small reduction and indirect type slip-line field in case of large reduction. Results of the analysis represent the relation between the reduction ratio and the die wall pressure, mean drawing stress through rough die. The limitation on the use of this slip-line field is described. When the reduction ratio is given, the optimum die angle is analyzed in this paper.

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A Study on Dose Distribution of Small Irradiation Field in the Electron Therapy (전자선 치료에 있어서 작은 조사면적의 선량분포에 관한 고찰)

  • Kim, Sung-Kyu;Shin, Sei-One;Kim, Myung-Se
    • Journal of Yeungnam Medical Science
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    • v.8 no.2
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    • pp.114-120
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    • 1991
  • In electron therapy, low melting point alloy is used for shaping of the field. Electron field shaping material affect the output factor as well as the collimator system. The output factors of electron beams for shaped fields from NELAC-1018 were measured using ionization chamber of Farmer type in water phantom. The output factors of electron beams depend on the incident energy, inherent collimator system and the size of shaped field. Obtained results were followings. 1. In the smaller applicator, output varied extremely according to extent of collimator opening. 2. The higher energy, the output is less varied according to treatment field at small field.

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Effect of Rice-Bundle size the harvesting performance with binder and the threshing performance (볏단크기의 변화가 바인더에 의한 수확작업과 탈곡작업에 미치는 영향)

  • 김성래;안수봉;김기대
    • Journal of Biosystems Engineering
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    • v.5 no.1
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    • pp.51-57
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    • 1980
  • It is desirable to increase the diameter of rice bundle harvested by Japanese reaper binder recently introduced into Korean farmers , since it is too small for stalking in the field for preliminary drying prior to threshing operation which is dominant procedure in rice harvesting . Accordingly, this study was conducted to analyze the effect of the size of rice-bundle on the performance of binder and self-feeding thresher. The results are summarized as follows : 1. The diameter of rice-bundle could be increased from $\phi$80-98 to $\phi$105.0-125.4 while the number of rice bundles per 10 a were reduced to 1200 from 1600. The time required for harvesting 10 a of rice was 81 minutes in small size bundles and 84 minutes in large size bundles and no statistical difference was obtained. 2 .The grain loss due to discharge and cutting were slightly increased with large size bundle compared to the small size but no statistical difference was obtained. The precision of operation and drying rate was not significantly different between small and large size bundles. 3. The unthreshed losses were the same between large and small sizes of rice bundles when self-feeding thresher was used. When 8 PS engine was used , continuous operation was possible for small size bundles , but 1.5seconds of time interval was necessary for large size buldles. 4. The consumption of binding twine was reduced to 603 from 820 meters with the larger bundles , and the labour requirement for stalking rice bundles in the field was also reduced to 1.83 form 2.50 man-hour per 10 a Therefore, harvesting cost can be reduced up to 26.5 percent by increasing the bundle size.

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A Study on Real-time Data Preprocessing Technique for Small Millimeter Wave Radar (소형 밀리미터파 레이더를 위한 실시간 데이터 전처리 방법 연구)

  • Choi, Jinkyu;Shin, Youngcheol;Hong, Soonil;Park, Changhyun;Kim, Younjin;Kim, Hongrak;Kwon, Junbeom
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.19 no.6
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    • pp.79-85
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    • 2019
  • Recently, small radar require the development of small millimeter wave radar with high distance resolution to disable the target's system with a single strike. Small millimeter wave radar with high distance resolution need to process large amounts of data in real time to acquire and track target. In this paper, we summarized the real-time data preprocessing method to process the large amount of data required for small millimeter wave radar. In addition, the digital IF(Intermediate Frequency) receiver, Window processing, and, DFT(Discrete Fourier Transform) functions presented by real-time data preprocessing are implemented using FPGA(Field Programmable Gate Array). Finally the implemented real-time data preprocessing module was applied to the signal processor for small millimeter wave radar and verified by performance test related to the real-time preprocessing function.

A Suggest on the Reclassification and Performance Criteria of Construction Material in Korean Public Procurement - Based on the Law of Purchasing Policy for Market Support of Small and Medium Business - (공공공사 직접구매 조달품목 재분류 및 성능기준 제안)

  • Yang, Jinkook;Choi, Yongho;Lee, Eunha;Lee, Sangbeom
    • Korean Journal of Construction Engineering and Management
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    • v.15 no.3
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    • pp.31-37
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    • 2014
  • "The Law of purchasing policy for market support of small and medium business" was legislated to support small and medium industry by expanding purchase and revised consistently for the activation. And then the government made the public construction direct purchase compulsory about design items designated by president on small and medium business based on this law. However, secureing quality, tardiness and field material staff's heavy duty were arisen from approximately 120 direct market purchase items. The legislative intent of law is in accord with Win-Win growth between major company and small and medium business. However material staff who works in the field based on this law has difficulties with material securing quality, JIT(Just In Time), cost push. This study reclassified procurement items of "the direct market purchase system" reasonably and then suggested performance criteria for evaluation. The suggested result will contribute to vatalize the direct market purchase system.

Harvesting Performance of the Prototype Small Combine for Buckwheat and Adlay

  • Yoo, Soonam;Lee, Changhoon;Lee, Beom Seob;Yun, Young Tae
    • Journal of Biosystems Engineering
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    • v.43 no.4
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    • pp.320-330
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    • 2018
  • Purpose: The aim of this study was to investigate the harvesting performance of a prototype small combine for buckwheat and adlay. Methods: The prototype small combine was designed and constructed. Its ratio of grain loss, ratio of output components in the grain outlet, and field capacity for harvesting buckwheat and adlay were analyzed through field tests. Results: The prototype small combine required a working width of about 0.6 to 0.7 m to harvest buckwheat. The maximum travel speed was about 0.36 m/. The total ratio of grain loss was about 21.6%, which consisted of 8.8% at the header and 12.8% at the dust outlet. The grain and the material other than grain (MOG) ratios at the grain outlet were 94.1% and 5.9% respectively. In the case of adlay harvest, the maximum working width was about 1.2 m, that is, two rows. The range of maximum travel speed was about 0.45 to 0.46 m/s. When adlay was harvested in one row, the total ratio of grain loss ranged from 36.3 to 42.8% according to the cutting height. The cutting height of 30 cm resulted in a higher total ratio of grain loss than 60 cm and 90 cm. When the cutting height was 60 cm, there was no significant change in the total ratio of grain loss according to the number of working rows and the stage of the primary transmission shift. The total ratio of grain loss ranged from 35.2 to 37.7%. The grain and the MOG ratios at the grain outlet ranged from 93.1 to 95.8% and from 4.2 to 6.9%, respectively. No significant difference was observed in relation to cutting height, number of working rows, and the stage of the primary transmission shift. Conclusions: The prototype small combine for harvesting miscellaneous cereal crops showed good potential for the efficient harvesting of buckwheat and adlay. However, to improve the harvesting performance, there seems to be a need to develop new crop varieties suitable for machine-based harvesting and improve the transmissions, reels, separation/cleaning systems.

Calculation of depth dose for irregularly shaped electron fields (부정형 전자선 조사면의 심부선량과 출력비의 계산)

  • Lee, Byoung-Koo;Lee, Sang-Rok;Kwon, Young-Ho
    • The Journal of Korean Society for Radiation Therapy
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    • v.14 no.1
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    • pp.79-84
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    • 2002
  • The main cause factor for effective the output, especially in small & irregular shaped field of electron beam therapy, are collimation system, insert block diameter and energy. In the absorption deose of treatment fields, we should consider the lateral build-up ratio (LBR), which the ratio of dose at a point at depth for a given circular field to the dose at the same point for a 'broad-field', for the same incident fluence and profile. The LBR data for a small circular field are used to extract radial spread of the pencil beam, ${\sigma}$, as a function of depth and energy. It's based on elementary pencil beam. We consider availability of the factor, ${\sigma}$, in the small & irregular fields electron beam treatment.

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