• Title/Summary/Keyword: Unit calculation

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Monitor Unit calculation through Excell program (Excell 프로그램을 통한 치료선량(M. U) 계산)

  • Lim, Guang-Chae;Cho, Eun-Ju;Cho, Sun-Hang
    • The Journal of Korean Society for Radiation Therapy
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    • v.11 no.1
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    • pp.28-32
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    • 1999
  • Verifying the treatment value(Monitor Unit) unnecessarily involves too many simple and repetitive calculation processes, that is, individual computation process using the data(PDD value, Scp Factor, SSD Factor, Tray Factor) on the data book. We intend to minimize the time required to check the Monitor Unit through computerized calculation. Using $^{\ast}(multiplication)$, /(division), +(sum), if function, among others, which are present in the Excell program, MS office program, the Monitor Unit was obtainable through A/P value, Scp Factor and PDD value, Wedge Factor. From the verification of the computations of Monitor Unit for 60 patients previously treated, we were able to obtain an error rate of ${\pm}0.028MU$. Computerized calculation of the Monitor Unit could save the burden of Technologist.

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Economic Dispatch Algorithm for Unit Commitment (기동정지계획을 위한 경제급전 알고리즘)

  • Park, Jeong-Do;Lee, Yong-Hoon;Kim, Ku-Han;Moon, Young-Hyun
    • Proceedings of the KIEE Conference
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    • 1999.07c
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    • pp.1506-1509
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    • 1999
  • This paper presents a new economic dispatch algorithm to improve the unit commitment solution while guaranteeing the near optimal solution without reducing calculation speed. The conventional economic dispatch algorithms have the problem that it is not applicable to the unit commitment formulation due to the frequent on/off state changes of units during the unit commitment calculation. Therefore, piecewise linear iterative method have generally been used for economic dispatch algorithm for unit commitment. In that method, the approximation of the generator cost function makes it hard to obtain the optimal economic dispatch solution. In this case, the solution can be improved by introducing a inverse of the incremental cost function. The proposed method is tested with sample system. The results are compared with the conventional piecewise linear iterative method. It is shown that the proposed algorithm yields more accurate and economical solution without calculation speed reduction.

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A design of transcendental function arithmetic unit for lighting operation of mobile 3D graphic processor (모바일 3차원 그래픽 프로세서의 조명처리 연산을 위한 초월함수 연산기 구현)

  • Lee, Sang-Hun;Lee, Chan-Ho
    • Proceedings of the IEEK Conference
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    • 2005.11a
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    • pp.715-718
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    • 2005
  • Mobile devices is getting to include more functions according to the demand of digital convergence. Applications based on 3D graphic calculation such as 3D games and navigation are one of the functions. 3D graphic calculation requires heavy calculation. Therefore, we need dedicated 3D graphic hardware unit with high performance. 3D graphic calculation needs a lot of complicated floating-point arithmetic operation. However, most of current mobile 3D graphics processors do not have efficient architecture for mobile devices because they are based on those for conventional computer systems. In this paper, we propose arithmetic units for special functions of lighting operation of 3D graphics. Transcendental arithmetic units are designed using approximation of logarithm function. Special function units for lighting operation such as reciprocal, square root, reciprocal of square root, and power can be obtained. The proposed arithmetic unit has lower error rate and smaller silicon area than conventional arithmetic architecture.

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Calculation of Pollutant Loadings from Stream Watershed Using Digital Elevation Model and Pollutant Load Unit Factors (발생부하원단위와 수치표고모형을 이용한 하천유역 오염부하량 산정)

  • Yang, Hong-Mo;Kim, Hyuk
    • Journal of the Korean Institute of Landscape Architecture
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    • v.29 no.1
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    • pp.22-31
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    • 2001
  • The purpose of this study is to compare calculated pollutant loadings using pollutant load unit factors and vector type coverage, and expected mean concentration(EMC) and raster type of digital elevation model(DEM). This study is also focusing on comparison of the advantages and the disadvantages of the two methods, and seeking for a method of calculation of pollutant loadings using DEM. Estimation of pollutant inputs using pollutant load unit factors has limitations in identifying seasonal variations of pollutant loadings. Seasonal changes of runoffs should be considered in the calculation of pollutant loadings from catchments into reservoirs. Evaluation of pollutant inputs using runoff-coefficient and EMC can overcome these drawbacks. Proper EMC and runoff-coefficient values for the Koeup stream catchments of the Koheung estuarine lake were drawn from review of related papers. Arc/Info was employed to establish database of spatial and attribute data of point and non-point pollutant sources and characteristics of the catchments. ArcView was used to calculate point and non-point pollutant loadings. Pollutant loads estimated with either unit factors-coverages, i.e., pollutant load unit factors and vector coverages f point sources and land use, or EMC and digital elevation mode(DEM) were compared with stream monitoring loads. We have found that some differences were shown between monitoring results and estimated loads by Unit Factors-Coverage and EMC-DEM. Monthly variations of pollutant loads evaluated with EMC-DEM were similar to those with monitoring result. The method using EMC-DEM can calculate accumulated flows and pollutant loads and can be utilized to identify stream networks. A future research on correcting the difference between vector type stream using flow direction grid and digitalizing vector type should be conducted in order to obtain more exact calculation of pollutant loadings.

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A Study on the Cooling Load of South and East Facing Apartment Houses (남향과 동향 집합주택의 냉방부하에 관한 연구)

  • 박근우;이경희
    • Journal of the Korean housing association
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    • v.11 no.2
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    • pp.129-137
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    • 2000
  • This study is about the difference of South and East facing Cooling load of Apartment s Houses using Dynamic Heat-flow Calculation. Therefore, the purpose of this study is come in to use Material for the Thermal Environments of Apartment Houses. The results of the analysis are below. (1) For the peak load of degree hour; The highest is "I" unit and the next high load is H, F, E, C, B, G, D and A unit for the south facing Apartment houses. The higher load is "H" unit and the next high load is I, E, F, B, C, G, D, A Unit for the east facing Apartment houses. (2) For the total load of degree day; The highest load is "I" unit and the next high load is H, G, F, E, C, B, D and A Unit for the south facing Apartment houses. The highest load is "H" unit and the next high load is I, G, E, F, B, C, D, A Unit for the east facing Apartment houses. (3) For the total load of degree day; The highest load is "H" Unit for the east facing Apartment houses and the Lowest load is "A" Unit for the south facing Apartment houses.is "A" Unit for the south facing Apartment houses.nt houses.

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The position servo-loop in the robot control system must be processed every sampling period by real-time

  • Ha, Young-Youl;Lee, In-Ho;Kim, Min-Soo;Kim, Jae-Hoon
    • 제어로봇시스템학회:학술대회논문집
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    • 2002.10a
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    • pp.121.1-121
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    • 2002
  • Calculation unit and peripheral units that are used to make the position controller are embedded to one chip FPGA. $\textbullet$ Feed-forward PID controller and interpolator in the calculation unit mitigate frequent context switching. $\textbullet$ The peripheral units reduce the size of the joints position control board. $\textbullet$ Because the calculation unit is designed with pipeline structure, it has the advantages to apply to the multi joints.

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A Design of 24-bit Floating Point MAC Unit for Transformation of 3D Graphics (3차원 그래픽의 트랜스포메이션을 위한 24-bit 부동 소수점 MAC 연산기의 설계)

  • Lee, Jungwoo;Kim, Woojin;Kim, Kichul
    • IEMEK Journal of Embedded Systems and Applications
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    • v.4 no.1
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    • pp.1-8
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    • 2009
  • This paper proposes a 24-bit floating point multiply and accumulate(MAC) unit that can be used in geometry transformation process in 3D graphics. The MAC unit is composed of floating point multiplier and floating point accumulator. When separate multiplier and accumulator are used, matrix calculation, used in the transformation process, can't use continuous accumulation values. In the proposed MAC unit the accumulator can get continuous input from the multiplier and the calculation time is reduced. The MAC unit uses about 4,300 gates and can be operated at 150 MHz frequency.

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Radioactivity Calculation Considering Kori Unit 1 Operation History for the Defected Baffle Former Bolts (고리1호기 가동이력을 고려한 손상 배플포머볼트 방사화 계산)

  • Young Jae Maeng;Hyun Chul Lee;Myeong Ho Lee;Seong Sik Hwang;Seung Jin Oh;Yun Suk Jang
    • Transactions of the Korean Society of Pressure Vessels and Piping
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    • v.19 no.1
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    • pp.20-26
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    • 2023
  • The defected baffle former bolts of Kori unit 1 were withdrawn to analyze the cause of damage and gamma-ray measurement is being scheduled. Prior to that, in order to calculate the specific radioactivity value of the baffle former bolt, a radioactivity calculation method considering the actual operation history of the nuclear power plant is introduced and the calculation results are shown. In particular, the radioactivity calculation method considering the operation history is obtained by defining the monthly contribution factor from the actual monthly operation history. As a result, the results considering operation history are 16-28% lower than the general radioactivity calculation results. These results can contribute to establish a reasonable but economical strategy when planning nuclear power plant decommissioning.

A Monitor Unit Verification Calculation in IMRT as a Dosimetry QA

  • Kung, J.H.;Chen, G.T.Y.;Kuchnir, F.T.
    • Proceedings of the Korean Society of Medical Physics Conference
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    • 2002.09a
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    • pp.68-73
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    • 2002
  • In standard teletherapy, a treatment plan is generated with the aid of a treatment planning system, but it is common to perform an independent monitor unit verification calculation (MUVC). In exact analogy, we propose and demonstrate that a simple and accurate MUVC in Intensity Modulated Radiotherapy (IMRT) is possible. We introduce a concept of Modified Clarkson Integration (MCI). In MCI, we exploit the rotational symmetry of scattering to simplify the dose calculation. For dose calculation along a central axis (CAX), we first replace the incident IMRT fluence by an azimuthally averaged fluence. Second, the Clarkson Integration is carried over annular sectors instead of over pie sectors. We wrote a computer code, implementing the MCI technique, in order to perform a MUVC for IMRT purposes. We applied the code to IMRT plans generated by CORVUS. The input to the code consists of CORVUS plan data (e.g., DMLC files, jaw settings, MU for each IMRT field, depth to isocenter for each IMRT field), and the output is dose contribution by individual IMRT field to the isocenter. The code uses measured beam data for Sc, Sp, TPR, (D/Mu)$\_$ref/ and includes effects from MLC transmission, and radiation field offset. On a 266 MHZ desktop computer, the code takes less than 15 sec to calculate a dose. The doses calculated with MCI algorithm agreed within +/- 3% with the doses calculated by CORVUS, which uses a 1cm x 1cm pencil beam in dose calculation. In the present version of MCI, skin contour variations and inhomogeneities were neglected.

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Calculation of Reactor Pressure Vessel Fluence Using TORT Code

  • Shin, Chul-Ho;Kim, Jong kyung
    • Proceedings of the Korean Nuclear Society Conference
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    • 1998.05b
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    • pp.771-776
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    • 1998
  • TORT is employed for fast neutron fluence calculation at the reactor pressure vessel. KORI Unit 1 reactor at cycle 1 is modeled for this calculation. Three-dimensional cycle averaged assembly power distributions for KORI Vnit 1 at cycle 1 are calculated by using the core physics code, NESTLE 5.0. The root mean square error is within 4.3% compared with NDR (Nuclear Design Report) far all burnup steps. The C/E (Calculated/Experimental) values for the in-vessel dosimeters distribute between 0.98 and 1.36. The most updated cross-section library. BUGLE-96 based on ENDF/B-VI is used for the neutron fluence calculation. The makimum fast neutron nun calculated on reactor pressure vessel for KORI Unit 1 operated for 411.41 effgctive full power days is 1.784x10$^{18}$ n/$\textrm{cm}^2$. The position of the maximum neutron fluence in RPV wall 1/4 T is nearby 60cm below the midplane at zero degree.

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