• Title/Summary/Keyword: Unit model

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An Attempt to Model Distributions of Machined Component Dimensions in Production

  • Cogun, Can;Kilinc, Biinyamin
    • Journal of Mechanical Science and Technology
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    • v.16 no.1
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    • pp.60-74
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    • 2002
  • In this study, normal, log-normal, triangular, uniform. Weibull, Erlang and unit beta probability density functions are tried to represent the behaviour of frequency distributions of workpiece dimensions collected from various manufacturing firms. Among the distribution functions, the unit beta distribution function is found to be the best fit using the chi-square test of fit. An attempt is made for the adoption of the unit beta model to x-bar charts of quality control in manufacturing. In this direction, upper and lower control limits (UCL and LCL) of x-bar control charts of dimension measurements are estimated for the beta model, and the observed differences between the beta and normal model control limits are discussed for the measurement sets.

A Study on the Evaluation Method for Durability Life of Vehicle,s ECU (자동차 제어기의 내구수명 평가방안 연구)

  • Kim, Byeong-Woo;Choi, Beom-Jin;Cho, Hyun-Duck;Lee, Do-Hee
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.57 no.2
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    • pp.208-213
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    • 2008
  • In order to assess the reliability of the electronics control unit for vehicles, accelerated life test model and procedure are developed. By using this method, failure mechanism and life distribution are analyzed. The main results are as follows : i) the main failure mechanism is degradation failure that is, junction destruction of a semiconductor resin by high temperature. ii) the life distribution of the electronics control unit for vehicles is fitted well to Weibull life distribution and the accelerated life model of that is fitted well to Arrhenius model. iii) at the result of the life distribution, accelerated life test method is developed, and test time for life assessment will be shortened by 5,000 hours by this test method.

The Design of Photobiological Active Molecular Model For Photodynamic Therapy

  • Choi, Chang-Shik
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2019.05a
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    • pp.521-524
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    • 2019
  • The design of photobiological active photosensitizing molecular model for photodynamic therapy has been attracted as a research for the development of cancer treatment, and has been interested in the effective method for cancer treatment and the photosensitizer having more stable wavelength. Furthermore, the development of photosensitizer has been already carried out from the first generation molecule to the third one, and the research of smart photosensitizer as the fourth generation has been requested. As a fact, the selective killing of the only cancer cell is very difficult problem, and the present photodynamic therapy has the problem of killing of the normal cell. So, I have designed the new modelling of photosensitizer having the smart recognizing unit and the magnetic nanoparticle as well as having the several effective recognizing unit. In particular, the new model design of the photosensitizer having lanthanide metal has suggested for the development of photodynamic therapy. The model design of these new photosensitizing molecules will be introduced in the poster section for the new turning point of the development of photosensitizer.

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Replacement Model after Extended Two-phase Warranty (연장된 이단계 보증 이후의 교체모형)

  • Jung, Ki Mun
    • Journal of Integrative Natural Science
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    • v.14 no.4
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    • pp.197-204
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    • 2021
  • Under the two-phase warranty, the warranty period is divided into two intervals, one of which is for renewing replacement warranty, and the other is for minimal repair warranty. Jung[13] discusses the two types of extended two-phase warranty models. In this paper, we suggest the replacement model after the extended two-phase warranty that has been proposed by Jung[13]. To determine the optimal replacement policy, we adopt the expected cost rate per unit time. So, the expressions for the total expected cost, the expected length of the cycle and the expected cost rate per unit time from the user's point of view are derived. Also, we discuss the optimal replacement policy and the uniqueness of the solution for the optimization. Furthermore, the numerical examples are provided to illustrate the proposed the replacement model.

A Reranking Model for Korean Morphological Analysis Based on Sequence-to-Sequence Model (Sequence-to-Sequence 모델 기반으로 한 한국어 형태소 분석의 재순위화 모델)

  • Choi, Yong-Seok;Lee, Kong Joo
    • KIPS Transactions on Software and Data Engineering
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    • v.7 no.4
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    • pp.121-128
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    • 2018
  • A Korean morphological analyzer adopts sequence-to-sequence (seq2seq) model, which can generate an output sequence of different length from an input. In general, a seq2seq based Korean morphological analyzer takes a syllable-unit based sequence as an input, and output a syllable-unit based sequence. Syllable-based morphological analysis has the advantage that unknown words can be easily handled, but has the disadvantages that morpheme-based information is ignored. In this paper, we propose a reranking model as a post-processor of seq2seq model that can improve the accuracy of morphological analysis. The seq2seq based morphological analyzer can generate K results by using a beam-search method. The reranking model exploits morpheme-unit embedding information as well as n-gram of morphemes in order to reorder K results. The experimental results show that the reranking model can improve 1.17% F1 score comparing with the original seq2seq model.

A Study on the Cost Estimating Method based on Spatial Unit Focused on Improving Limitation Caused by Lack of Spatial Information of the Cost Based on Work Type (공간단위 공사비 산정방법에 관한 연구 - 공종별 공사비의 공간정보 부재로 인한 한계점 개선을 중심으로 -)

  • Lee, Ki-Sang
    • Korean Journal of Construction Engineering and Management
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    • v.12 no.3
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    • pp.131-139
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    • 2011
  • In this Study, the Cost of Public Facility Construction in the VE Cost Model, and the Progress of the Construction Site Management, and Cost due to the Lack of Cpatial Information in Dispute Cost Work Type Recognize the limits of Historical Information, and to Overcome the Perception of Cost and Space Systems Unit In the Process of Transition that Began Seeking Ways to Improve Through this Study, Different Parts of the Proposed Area of Construction Work Unit System, the Core of Calculating Hourly and Detailed Engineering Information and Cost Information Generated Extension to Configure the Construction Unit in Every Space, Every Work Unit System, All Materials That Make Up Work Unit System, Unit Labor Costs, And All of the Configuration Items Enables Precise And Multidimensional Understanding is That.

Spatial Analyses of the 3-Bedroom Apartment Unit Plans from 1979 to the Present in Beijing, China (중국 아파트 단위주호 평면의 공간 분석 - 1979년~현재 베이징 3침실형 아파트를 중심으로 -)

  • Lian, Shuai;Choi, Jaepil
    • Journal of the Architectural Institute of Korea Planning & Design
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    • v.35 no.4
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    • pp.53-60
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    • 2019
  • This study intends to examine the changes found in the unit floor plans of the apartments built in Beijing from 1979 to 2018. For the 3 - bedroom type apartments, 40 unit floor plans were collected, and the changes of integration values of each space were analyzed periodically in four phases. The unit floor plans are analyzed in the context of the Space Syntax Model and compared to the lifestyle and societal changes in China. The results of the study indicate the followings: As time went by, the living room and the dining room were separated from each other with the increasing area of the apartment unit floor plans. The function of the integrated living room was dispersed, and the integration of the living room and the dining room decreased with the change of time. In the third phase, the dining room occupied the center of the unit floor plans with the highest integration value; Chinese people prefer to place the kitchen in the relatively deep place in order to prevent oil and smoke caused by their cooking habits like stir-fry; The privacy of the master bedroom has been strengthened.

Is the Fama French Three-Factor Model Relevant? Evidence from Islamic Unit Trust Funds

  • Shaharuddin, Shahrin Saaid;Lau, Wee-Yeap;Ahmad, Rubi
    • The Journal of Asian Finance, Economics and Business
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    • v.5 no.4
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    • pp.21-34
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    • 2018
  • The study tests the Fama and French three-factor model by using the newly created Islamic equity style indices. Based on a dataset from May 2006 to April 2011, the three-factor model is tested based on returns of Islamic unit trust funds using the Generalized Method of Moments (GMM) methodology. The sample period is also divided between periods before and after the Global Financial Crisis in August 2008 to test for robustness, and the Bai and Perron (2003) multiple structural break test was used to determine the structural break in the series. The analysis shows that the Fama and French model is valid for Islamic unit trust funds before and after the collapse of Lehman Brothers. The result further indicates the reversal of size effect. As for trading strategies, value funds outperform growth funds by annualized 3.13 percent for the full period. During pre-crisis period, value funds perform better than growth funds while in post-crisis, size factor yields better return than other strategies. As policy suggestion, fund managers need to be aware of the reversal of size effect, and they need to ensure a more transparent stock selection process so that investors can make an informed decision in their asset allocation.

Estimation Model for Optimum Probabilistic Rainfall Intensity on Hydrological Area - With Special Reference to Chonnam, Buk and Kyoungnam, Buk Area - (수문지역별 최적확률강우강도추정모형의 재정립 -영.호남 지역을 중심으로 -)

  • 엄병헌;박종화;한국헌
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.38 no.2
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    • pp.108-122
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    • 1996
  • This study was to introduced estimation model for optimum probabilistic rainfall intensity on hydrological area. Originally, probabilistic rainfall intensity formula have been characterized different coefficient of formula and model following watersheds. But recently in korea rainfall intensity formula does not use unionize applyment standard between administration and district. And mingle use planning formula with not assumption model. Following the number of year hydrological duration adjust areal index. But, with adjusting formula applyment was without systematic conduct. This study perceive the point as following : 1) Use method of excess probability of Iwai to calculate survey rainfall intensity value. 2) And, use method of least squares to calculate areal coefficient for a unit of 157 rain gauge station. And, use areal coefficient was introduced new probabilistic rainfall intensity formula for each rain gauge station. 3) And, use new probabilistic rainfall intensity formula to adjust a unit of fourteen duration-a unit of fifteen year probabilistic rainfall intensity. 4) The above survey value compared with adjustment value. And use three theory of error(absolute mean error, squares mean error, relative error ratio) to choice optimum probabilistic rainfall intensity formula for a unit of 157 rain gauge station.

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ASSESSMENT OF CORE BYPASS FLOW IN A PRISMATIC VERY HIGH TEMPERATURE REACTOR BY USING UNIT-CELL EXPERIMENT AND CFD ANALYSIS (단위-셀 실험과 전산유체해석을 통한 블록형 초고온가스로의 노심우회유량 평가)

  • Yoon, S.J.;Jin, C.Y.;Kim, M.H.;Park, G.C.
    • Journal of computational fluids engineering
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    • v.14 no.2
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    • pp.59-67
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    • 2009
  • An accurate prediction of the bypass flow is of great importance in the VHTR core design concerning the fuel thermal margin. Nevertheless, there has not been much effort in evaluating the amount and the distribution of the core bypass flow. In order to evaluate the behavior and the distribution of the coolant flow, a unit-cell experiment was carried out. Unit-cell is the regular triangular section which is formed by connecting the centers of three hexagonal blocks. Various conditions such as the inlet mass flow rate, block combinations and the size of bypass gap were examined in the experiment. CFD analysis was carried out to analyze detailed characteristics of the flow distribution. Commercial CFD code FLUENT 6.3 was validated by comparing with the experimental results. In addition, SST model and standard k-$\varepsilon$ model were validated. The results of CFD simulation show good agreements with the experimental results. SST model shows better agreement than standard k-$\varepsilon$ model. Results showed that block combinations and the size of the bypass gap have an influence on the bypass flow ratio but the inlet mass flow rate does not.