• 제목/요약/키워드: Sectional size

검색결과 518건 처리시간 0.025초

한국상장기업 정보기술의 인력집중도 결정요인 (Determinants of Information Technology Personnel Size in Korean Listed Companies:A Cross-Sectional Analysis)

  • 홍창목;정진향
    • 한국IT서비스학회지
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    • 제12권4호
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    • pp.91-108
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    • 2013
  • In this study, we empirically examine cross-sectional determinants of IT personnel size of Korean listed companies from year 2004 to year 2009. Also, cross-sectional determinants of IT personnel size involved in managing internal control over financial reporting (hereafter, "ICFR") were examined. IT personnel or IT workers are recognized as critical intangible resources comprising firm's IT capability. Although IT personnel are regarded as important resources, there are not much information about factors explaining the size of firms' IT personnel. Fortunately, the Korean governmant regulates that every listed companies should dislclose the number of IT workers and ICFR-related IT personnel in their annual reports. This study utilizes the mandatorily disclosed IT personnel data to analyze cross-sectional determinants of korean listed companies' IT personnel size. Empirical results show that profitability, uncertainty, leverage, industry types are statistically significant factors associated with the size of IT personnel.

구간해석방법을 통한 새로운 비구형 입자성장해석 모델 (A New Model for the Analysis of Non-spherical Particle Growth Using the Sectional Method)

  • 정재인;최만수
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2000년도 춘계학술대회논문집B
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    • pp.416-421
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    • 2000
  • We have developed a simple model for describing the non-spherical particle growth phenomena using modified 1-dimensional sectional method. In this model, we solve simultaneously particle volume and surface area conservation sectional equations which consider particles' irregularities. From the correlation between two conserved properties of sections, we can predict the evolution of the aggregates' morphology. We compared this model with a simple monodisperse-assumed model and more rigorous two dimensional sectional model. For the comparison, we simulated silica and titania particle formation and growth in a constant temperature reactor environment. This new model shows a good agreement with the detailed two dimensional sectional model in total number concentration, primary particle size. The present model can also successfully predict particle size distribution and morphology without costing very heavy computation load and memory needed for the analysis of two dimensional aerosol dynamics.

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MRI 보어 구경에 따른 검사 시 실효 단면적 분석 (Analysis of Actual Cross-Sectional Area During Scanning According to MRI Bore Size)

  • 정현근;정현도;김성호;전민철;유세종;고현철;조용현
    • 대한의용생체공학회:의공학회지
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    • 제41권6호
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    • pp.219-227
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    • 2020
  • In this study, we tried to quantify the actual cross-sectional area inside the bore when scanning by the MRI system with various bore sizes. To this end, a comparative analysis was conducted by both of blueprint of each MRI equipment and actual measurement in the field. As a result of analysis, ACSA(Actual Cross-Sectional Area) in Ingenia CX, Elition X, uMR 780, Omega, Vida, Lumina, Architect, Premier is recorded as 171230, 232150, 242100, 309332, 230760, 230760, 229380 and 235990 ㎟, respectively ACSA% was 60.6, 60.3, 73.0, 70.0, 60.0, 60.0, 59.6, and 61,3%. In addition, DTB (Distance from Table top to Bore top) recorded 400, 407, 445, 495, 405, 405, 405, 403, and 412 mm. Through this study, it was confirmed that there is a difference between the bore size according to each MRI system and the actual cross-sectional area during MRI scanning. Accordingly, if we consider the internal actual area just not bore size at the clinical site, useful diagnostic images can be obtained in the end with better convenience.

새로운 비구형 입자 성장 해석 모델 (A New Model for the Analysis of Non-Spherical Particle Growth)

  • 정재인;최만수
    • 대한기계학회논문집B
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    • 제24권7호
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    • pp.1020-1027
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    • 2000
  • A simple model for describing the non-spherical particle growth phenomena has been developed. In this model, we solve simultaneously particle volume and surface area conservation sectional equations that consider particles' non-sphericity. From the correlation between two conserved properties of sections, we can predict the evolution of the aggregates' morphology. This model was compared with a simple monodisperse-assumed model and more rigorous two-dimensional sectional model. For comparison, formation and growth of silica particles have been simulated in a constant temperature reactor environment. This new model showed good agreement with the detailed two-dimensional sectional model in total number concentration and primary particle size. The present model successfully predicted particle size distribution and morphology without costing very heavy computation load and memory needed for the analysis of two dimensional aerosol dynamics.

Earnings Forecasts and Firm Characteristics in the Wholesale and Retail Industries

  • LIM, Seung-Yeon
    • 유통과학연구
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    • 제20권12호
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    • pp.117-123
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    • 2022
  • Purpose: This study investigates the relationship between earnings forecasts estimated from a cross-sectional earnings forecast model and firm characteristics such as firm size, sales volatility, and earnings volatility. Research design, data and methodology: The association between earnings forecasts and the aforementioned firm characteristics is examined using 214 firm-year observations with analyst following and 848 firm-year observations without analyst following for the period of 2011-2019. I estimate future earnings using a cross-sectional earnings forecast model, and then compare these model-based earnings forecasts with analysts' earnings forecasts in terms of forecast bias and forecast accuracy. The earnings forecast bias and accuracy are regressed on firm size, sales volatility, and earnings volatility. Results: For a sample with analyst following, I find that the model-based earnings forecasts are more accurate as the firm size is larger, whereas the analysts' earnings forecasts are less biased and more accurate as the firm size is larger. However, for a sample without analyst following, I find that the model-based earnings forecasts are more pessimistic and less accurate as firms' past earnings are more volatile. Conclusions: Although model-based earnings forecasts are useful for evaluating firms without analyst following, their accuracy depends on the firms' earnings volatility.

압축을 받는 강관의 단면보강에 따른 좌굴특성 검토 (The Study on the Buckling Characteristics of Partially Increased Sectional Area for Compressed Circular Steel Tube)

  • 권영환;정환목;박상훈;석창목
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 1999년도 가을 학술발표회 논문집
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    • pp.187-193
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    • 1999
  • As the slenderness ratio increases, it is necessary to examine the increased sectional area of member by means of increasing buckling strength because the sectional area of compressive member is designed in accordance with buckling. In this reason tn reinforce insufficient strength it don not have to reinforce the whole sectional area of member. Force of member can be increased in a way to restrict buckling mode by means of the partially increased sectional area of member. Therefore, in this study, we put emphasis on compressive members among many members that constitute space frame and try to get basic data about the reinforcement of space frame by means of investigating the bucking characteristic according to the size and length of partially increased sectional area of member.

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열교환기 브레이징 결함의 유형 분류 및 형상 디스플레이 (Type Classification and Shape Display of Brazing Defect in Heat Exchanger)

  • 김진영
    • 제어로봇시스템학회논문지
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    • 제19권2호
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    • pp.171-176
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    • 2013
  • X-ray cross-sectional image-based inspection technique is one of the most useful methods to inspect the brazing joints of heat exchanger. Through X-ray cross-sectional image acquisition, image processing, and defect inspection, the defects of brazing joints can be detected. This paper presents a method to judge the type of detected defects automatically, and to display them three-dimensionally. The defect type is classified as unconnected defect, void, and so on, based on location, size, and shape information of defect. Three-dimensional display which is realized using OpenGL (Open Graphics Library) will be helpful to understand the overall situation including location, size, shape of the defects in a test object.

변동구간분할법을 이용한 흡습성 에어로졸의 거동 해석 (An Analysis of the Hygroscopic Aerosol Behavior Using the Moving Sectional Method)

  • 박재우;김희동
    • 한국분무공학회지
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    • 제3권4호
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    • pp.25-34
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    • 1998
  • Hygroscopic aerosols can rapidly grow in size by steam condensation even under subsaturated steam conditions. Much efforts have been made to handle this process, but there have been computational difficulties in handling the condensational growth of hygroscopic aerosols by contentional methods. A recently released computer code, CONTAIN 2.0, employs a new technique called Moving Sectional Method(MSM) to handle the growth of hygroscopic aerosols. As a part of the model verification efforts, we have used the code to simulate the VANAM M3U hygroscopic aerosol experiment. We assess the accuracies of the new MSM and the conventional Fixed Sectional Method(ESM) based on the simulation results. Also presented are discussions about the robustness of the MSM.

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Prediction Model of the Exit Cross Scetional Shape in Round-Oval -round Pass Rolling

  • Lee, Young seog;Gert Goldhahn
    • International Journal of Precision Engineering and Manufacturing
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    • 제2권1호
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    • pp.87-93
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    • 2001
  • A reliable analytic model that determines the exit cross sectional shape a workpiece(material) in round-oval (oroval-round) pass sequence has been developed. The exit cross sectional shape of an outgoing workpiece is predicted by using the linear interpolation of the radius of curvature of an incoming workpiece and that of roll groovw to the roll axis direction. The requirements placed on the choice of the weighting function were to ensure boundary conditions specified. The validity of the analytic model has been examined by not rod rolling experiment with the roll gap and specimen size changed. The exit cross sectional shape and area of the workpiece predicted by the proposed analytic model were good agreement with those obtained experimentally. We found that the analytic model has not only simplicity and accuracy for practical usage but also save a large amount of computational time compared with finite element method.

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선재압연공정의 소재 자유표면 형상예측 (Prediction of Stress Free Surface Profile of Wrokpiece in Rod Rolling Process)

  • 이영석;김영호;진영은
    • 한국정밀공학회지
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    • 제17권9호
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    • pp.174-180
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    • 2000
  • A reliable analytic model that determines the cross sectional shape of a workpiece(material) in round-oval(or oval-round) pass sequence has been developed. the cross sectional shape of an outgoing workpiece is predicted by using the linear interpolation of the radius of curvature of an incoming workpiece and that of roll groove to the roll axis direction. The requirements we placed on the choice of the weighting function were to ensure boundary conditions specified. The validity of the analytic model has been examined by hot rod rolling experiment with the roll gap and specimen size changed. The cross sectional shape and area of a workpiece predicted by the proposed analytic model were good agreement with those obtained experimentally. It was found that the analytic model has not only simplicity and accuracy for practical usage but also save a large amount of computational time compared with finite element method.

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