• Title/Summary/Keyword: Recalculation

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Recalculation of Monthly Weather Table for Construction Standard Cost Estimating on Aerial Photogrammetry (항공사진측량 품셈 개정을 위한 월별천후표 재계산)

  • Song, DongSeob
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.37 no.6
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    • pp.571-577
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    • 2019
  • Since the introduction of digital cameras in an aerial-photogrammetry field on 2006, the technological paradigm related to the photogrammetry has been shifting from the analog types to digital types. However, current construction standard cost for the aerial-photogrammetry and the digital mapping are being mixed with analog-based concepts and digital-based methods. In the current standard cost, the monthly weather table is closely related to the calculation of the number of flying days in a taking of aerial photograph. The current monthly weather table uses the results calculated from the observation data of total cloud amount from 1999 to 2007. In this study, the monthly weather table was calculated using the total cloud data during ten years from 2009 to 2018. As a result, the newly calculated number of clear days for 29 stations was analyzed as 44 days decreased by 6 days. The maximum number of clear days decreased in Jinju as 23 days, and the highest decreased clearing days was February.

A Study on the Design of OSPF Area and Data Flow in the Tactical Data Networks (전술 데이터망에서 OSPF Area 설정과 데이터 흐름에 관한 연구)

  • Kwon, Soo-Gab;Jeong, Kyu-Young;Kim, Jeong-Ho
    • The KIPS Transactions:PartC
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    • v.14C no.3 s.113
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    • pp.267-276
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    • 2007
  • In OSPF, the larger and more unstable the area, the greater the likelihood for performance problems associated with routing protocol recalculation. Generally, an area should have no more than 50 routers. Areas with unstable links should be smaller. Military tactical data network is used for military operations during war-time. It consists of wireless network for mobility of node. Thus, it has low-bandwidth and unstable property. In addition, it is expected that many kinds of router-failure, Link-failure and recovery at emergency period. However, Military tactical data network is designed with about one and half times the number of recommendation. This paper proves that the traffic is limited by the increase of re-calculation of area.

Development of an Object-oriented Finite Element Model through Iterative Method Ensuring Independency of Elements (요소 독립성이 유지되는 반복해법에 의한 객체지향 유한요소모델 개발)

  • Lee, Han-Ki;Kim, Tae-Gon;Lee, Jeong-Jae
    • Journal of The Korean Society of Agricultural Engineers
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    • v.54 no.2
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    • pp.115-125
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    • 2012
  • Application of the Object-oriented Programming (OOP) method to the Finite Element Model (FEM) program has various strengths including the features of encapsulation, polymorphism and inheritance. However, this technique should be based upon a premise that the independency of the object method and data to be used is guaranteed. By attempting to apply the OOP to the FEM, existing researches go against the independency of the OOP which is an essential feature of the method. The reason is this: existing researches apply the OOP to modules in accordance with analysis procedures, although the data to be used is classified as an element unit in the FEM. Therefore, the required independency cannot be maintained as whole stiffness matrices and boundary conditions are combined together. Also, solutions are sought from analysis module after data is regrouped at the pre-processor, and their results are analyzed during the post-processor. As this is similar to a batch processing, it cannot use data at analysis, and recalculation should be done from the beginning if any condition is changed after the analysis is complete, which are limitations of the existing researches. This research implemented the Object-orientation of elements so that the three features of the OOP (i.e. encapsulation, polymorphism and inheritance) can be guaranteed and their independency maintained as a result. For this purpose, a model called 'Object-oriented Finite element Model ensuring the Independency of Elements (OFMIE)', which enables the analysis of targets through mutual data exchanges within instance, was developed. In conclusion, the required independency was achieved in the instance of the objected elements and the analysis results of previous conditions could be used for the analysis after changes. The number of repetitive calculations was reduced by 75 per cent through this gradual analysis processes.

Recommended Intake and Dietary Intake of Vitamin A for Koreans by Unit of Retinol Activity Equivalent (RAE(레틴올활성당량) 단위로 환산한 한국인의 비타민 A 권장섭취량 및 식이 섭취량 변화)

  • Kim, Youngnam
    • Korean Journal of Community Nutrition
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    • v.21 no.4
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    • pp.344-353
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    • 2016
  • Objectives: New retinol activity equivalent (RAE) was introduced as vitamin A unit in Dietary Reference Intake (DRI) for Koreans 2015. The purpose of this study was to evaluate the adequacy of 2015 reference intake (RI) of vitamin A in RAE unit by the comparison with RI and dietary intake of vitamin A. Methods: Analyses on RI of vitamin A were based on the Recommended Dietary Allowances (RDA) for Koreans (1962~2000) and DRIs for Koreans (2005~2015). Analyses on Koreans dietary intake of vitamin A were based on the Korea National Health and Nutrition Examination Survey (KNHNES) reports (1969-2014). For recalculation of RI and dietary intake of vitamin A in RE to RAE, 2013 Koreans intake of retinol: carotenoids ratio of 13: 87 was applied. Results: RI of vitamin A was 600~750 RE for Korean adult, and 339~425 RAE when calculated by applying the retinol and carotenoids intake ratio. Vitamin A intakes of Koreans were <100% RI, 267~668 RE from 1969 to 2001. From 2005, vitamin A intake had increased to >700 RE, >100% RI. When vitamin A intake was converted from RE to RAE (2005~2014), 718~864 RE became 405.8~488.1 RAE, decreased to 56.5% level. The recent 2015 RI of vitamin A is 850 RAE, two times of 2005 & 2010 RI of 425 RAE for adult male. Conclusions: When nutritional status of vitamin A was assessed for Koreans using the estimated average requirement (EAR) of 2015 (570, 460 RAE for male, female adults, respectively), ratio of deficient people increased significantly when judged based on the previous intake of Koreans, <490 RAE. We needs to examine the 2015 RI (EAR) of vitamin A, find a way to measure the accurate intake of dietary vitamin A, and to increase the dietary intake of this vitamin.

Modified Microstrip Filters Improving the Suppression Performance of Harmonic Signals (고조파 감쇠특성을 향상시킨 변형된 마이크로스트립 여파기)

  • 김봉수;이재욱;송명선
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.13 no.10
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    • pp.1054-1060
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    • 2002
  • In this paper, a new parallel-coupled-line microstrip BPF(BandPass Filter) improving the suppression performance of 2nd harmonic signals is studied. Using the consecutive pattern in coupled-line, the desired passband performance is improved and harmonic passband signal is rejected. Recalculation of classical filter design parameters(space-gap between lines, line widths and lengths) is not required. That is, after using the classical design methodology for parellel-coupled-line BPF, new filters can be easily realized by inserting periodic patterns in coupled-line. To investigate the validity of this novel technique, order-3 Butterworth BPF centered at 2.5 GHz with a 10 % FBW(Fractional Bandwidth) and order-5 Chebyshev BPF centered at 10 GHz with a 15 % FBW were used. When five and three square grooves are used, over 30 dB harmonic suppression at 2nd harmonic is achieved in simulation and experiment.

Incremental Processing Scheme for Graph Streams Considering Data Reuse (데이터 재사용을 고려한 그래프 스트림의 점진적 처리 기법)

  • Cho, Jungkweon;Han, Jinsu;Kim, Minsoo;Choi, Dojin;Bok, Kyoungsoo;Yoo, Jaesoo
    • The Journal of the Korea Contents Association
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    • v.18 no.1
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    • pp.465-475
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    • 2018
  • Recently, as the use of social media and IoT has increased, large graph streams has been generating and studies on real-time processing for them have been actively carrying out. In this paper we propose a incremental graph stream processing scheme that reuses previous result data when the graph changes continuously. We also propose a cost model to selectively perform incremental processing and static processing. The proposed cost model computes the predicted value of the detection cost and the processing cost of the recalculation area based on the actually processed history and performs the incremental processing when the incremental processing is more profit than the static processing. The proposed incremental processing increases the efficiency by processing only the part that changes when the graph update occurs. Also, by collecting only the previous result data of the changed part and performing the incremental processing, the disk I/O costs are reduced. It is shown through various performance evaluations that the proposed scheme outperforms the existing schemes.

A Study on Optimum Design Analysis of Bolt Locations for Metal Joint Parts of Railway Composite Bogie Frames using Sub-modeling Method (서브모델링 기법을 이용한 철도차량 복합재 대차프레임의 금속재 체결부 볼트 위치 최적화 해석 연구)

  • Kim, Jun-Hwan;Shin, Kwang-Bok;Ko, Hee-Young;Kim, Jung-Seok
    • Composites Research
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    • v.23 no.6
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    • pp.19-25
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    • 2010
  • This paper describes the optimum design of bolt locations for metal joint parts of railway bogie frame made of glass fiber/epoxy 4-harness satin woven laminate composite and PVC foam core. The optimum design analysis was done by sub-problem approximation method using Ansys Parameter Design Language(APDL). The sub-modeling method was introduced to conduct the detailed recalculation for the only target parts and reduce calculating time. The structural analysis for composite bogie frame was performed according to JIS E 4207. The results showed that the optimum design analysis using sub-modeling method was able to obtain faster and more precise results than that of the entire model by the control of mesh size for the target parts, and the maximum Von-Mises stress has been reduced in comparison with its original dimensions due to the optimum design of bolt locations.

Zero Torque Control of Switched Reluctance Motor for Integral Charging (충전기 겸용 스위치드 릴럭턴스 전동기의 제로토크제어)

  • Rashidi, A.;Namazi, M.M;Saghaian, S.M.;Lee, D.H.;Ahn, J.W.
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.66 no.2
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    • pp.328-338
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    • 2017
  • In this paper, a zero torque control scheme adopting current sharing function (CSF) used in integrated Switched Reluctance Motor (SRM) drive with DC battery charger is proposed. The proposed control scheme is able to achieve the keeping position (KP), zero torque (ZT) and power factor correction (PFC) at the same time with a simple novel current sharing function algorithm. The proposed CSF makes the proper reference for each phase windings of SRM to satisfy the total charging current of the battery with zero torque output to hold still position with power factor correction, and the copper loss minimization during of battery charging is also achieved during this process. Based on these, CSFs can be used without any recalculation of the optimal current at every sampling time. In this proposed integrated battery charger system, the cost effective, volume and weight reduction and power enlargement is realized by function multiplexing of the motor winding and asymmetric SR converter. By using the phase winding as large inductors for charging process, and taking the asymmetric SR converter as an interleaved converter with boost mode operation, the EV can be charged effectively and successfully with minimum integral system. In this integral system, there is a position sliding mode controller used to overcome any uncertainty such as mutual inductance or DC offset current sensor. Power factor correction and voltage adaption are obtained with three-phase buck type converter (or current source rectifier) that is cascaded with conventional SRM, one for wide input and output voltage range. The practicability is validated by the simulation and experimental results by using a laboratory 3-hp SRM setup based on TI TMS320F28335 platform.

Verification and validation of isotope inventory prediction for back-end cycle management using two-step method

  • Jang, Jaerim;Ebiwonjumi, Bamidele;Kim, Wonkyeong;Cherezov, Alexey;Park, Jinsu;Lee, Deokjung
    • Nuclear Engineering and Technology
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    • v.53 no.7
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    • pp.2104-2125
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    • 2021
  • This paper presents the verification and validation (V&V) of a calculation module for isotope inventory prediction to control the back-end cycle of spent nuclear fuel (SNF). The calculation method presented herein was implemented in a two-step code system of a lattice code STREAM and a nodal diffusion code RAST-K. STREAM generates a cross section and provides the number density information using branch/history depletion branch calculations, whereas RAST-K supplies the power history and three history indices (boron concentration, moderator temperature, and fuel temperature). As its primary feature, this method can directly consider three-dimensional core simulation conditions using history indices of the operating conditions. Therefore, this method reduces the computation time by avoiding a recalculation of the fuel depletion. The module for isotope inventory calculates the number densities using the Lagrange interpolation method and power history correction factors, which are applied to correct the effects of the decay and fission products generated at different power levels. To assess the reliability of the developed code system for back-end cycle analysis, validation study was performed with 58 measured samples of pressurized water reactor (PWR) SNF, and code-to-code comparison was conducted with STREAM-SNF, HELIOS-1.6 and SCALE 5.1. The V&V results presented that the developed code system can provide reasonable results with comparable confidence intervals. As a result, this paper successfully demonstrates that the isotope inventory prediction code system can be used for spent nuclear fuel analysis.

A Study on Improvement Measures of Energy Recovery Efficiency through Analysis of Operational Status of Municipal Solid Waste Incineration Facilities (생활폐기물 소각시설의 운영 실태 분석을 통한 에너지회수 효율 개선방안 검토)

  • Park, Sang-Jin;Phae, Chae-gun
    • Journal of Korea Society of Waste Management
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    • v.35 no.8
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    • pp.762-769
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    • 2018
  • This study was carried out to examine the improvement plan by analyzing the characteristics of imported wastes, operation rate, and benefits of energy recovery for incineration facilities with a treatment capacity greater than 50 ton/day. The incineration facility capacity increased by 3,280 tons over 15 years, and the actual incineration rate increased to 2,783 ton/day. The operation rate dropped to 76% in 2010 and then rose again to 81% in 2016. The actual calorific value compared to the design calorific value increased by 33.8% from 94.6% in 2002 to 128.4% in 2016. The recovery efficiency decreased by 29% over 16 years from 110.7% to 81.7% in 2002. Recovery and sales of thermal energy from the incinerator (capacity 200 ton/day) dominated the operation cost, and operating income was generated by energy sales (such as power generation and steam). The treatment capacity increased by 11% to 18% after the recalculation of the incineration capacity and has remained consistently above 90% in most facilities to date. In order to solve the problem of high calorific value waste, wastewater, leachate, and clean water should be mixed and incinerated, and heat recovery should be performed through a water-cooled grate and water cooling wall installation. Twenty-five of the 38 incineration facilities (about 70%) are due for a major repair. After the main repair of the facility, the operation rate is expected to increase and the operating cost is expected to decline due to energy recovery. Inspection and repair should be carried out in a timely manner to increase incineration and heat energy recovery efficiencies.