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An improvement of software sizing and cost estimation model with function point methods (기능 점수를 이용한 소프트웨어 규모 및 비용산정 방안에 관한 연구)

  • 김현수
    • Korean Management Science Review
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    • v.14 no.1
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    • pp.131-149
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    • 1997
  • Software cost estimation is an important both for buyers and sellers(developers). We reviewed domestic and foreign researches and practices on software cost estimation with function point method comprehensively, In this paper, we derived four promising alternative function point models. They are an IFPUG(International Function Point User Group)-based model(Model I), a shorthand model for client/sever software systems(Model II), a data-oricnted model for relatively large software projects(Model III), and a general- purpose function point model for non business application softwares as well as business applications(Model IV). Empirical data shows that Model I, II, and IV are very useful function point models. In particular, model II and IV look very useful models since they are concise and accurate. These models can be incorporated in a new improved guideline for software cost estimation. General opinion survey shows that Model I, II and IV are preferable. There are no significant differences in preference between buyers and sellers. The survey also shows that users think function point method is better than step(line of code)-oriented cost estimation methods in many ways including objectivity and estimation accuracy.

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Sensitivity Analysis on Off-Design Performance of Centrifugal Compressor Due to the Parameters of Two-zone Model and TEIS Model (두영역 모델과 직렬두요소 모델의 변수에 의한 원심 압축기 탈설계 성능의 민감도 분석)

  • Yoon, Sung-Ho;Baek, Je-Hyun
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.24 no.6
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    • pp.834-844
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    • 2000
  • In this study, an off-design performance analysis procedure is developed based on Two-zone model and TEIS model. In Two-zone model, there are both primary zone and secondary zone for an isentropic core flow and an average of all non-isentropic streamtubes respectively. The level of the core flow diffusion in an impeller is calculated by using TEIS model which regards the impeller as two successive rotating elements in series. At impeller exit, the mixing process occurs with an increase in entropy, that is to say, a decrease in total pressure. In loss models including Two-zone and TEIS model, some empirical parameters have a great influence on overall performance curve. So these parameters' influences on the overall performance curve are investigated and compared with experimental data.

An EOQ Model for Deteriorating Items with Linearly Increasing Demand

  • Kim, Dae-Hong
    • Journal of Korean Institute of Industrial Engineers
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    • v.20 no.3
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    • pp.117-124
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    • 1994
  • In this paper an inventory model is presented for determining the ordering schedule in which the demand rate is changing linearly with time and the decay is assumed to be a constant rate of the on-hand inventory. An easy to use heuristic is developed to find the times and sizes of replenishments so as to keep the total of ordering, inventory carrying and deteriorating costs as low as possible. Solutions of the model to test problems show that our heuristic model outperforms other existing models in the literature without sacrificing the computational complexity. When there is no deterioration, the model developed is related to the corresponding model of nondeteriorating items.

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Estimation of Nonlinear Response for Moment Resisting Reinforced Concrete Frames Using Equivalent SDOF System (등가 1 자유도계에 의한 철근콘크리트 건물의 비선형 동적해석의 검토)

  • 전대한;노필성
    • Proceedings of the Earthquake Engineering Society of Korea Conference
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    • 2003.09a
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    • pp.205-212
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    • 2003
  • To evaluate the seismic performance of multistory building structures use an equivalent SDOF model. This paper presents a method of converting a MDOF system into an equivalent SDOF model. The principal objective of this investigation is to evaluate appropriateness of converting method through perform nonlinear time history analysis of a multistory building structures and an equivalent SDOF model. The hysteresis rules to be used an equivalent SDOF model is obtained from the pushover analysis. The conclusion of this study is following; A method of converting a MDOF system into an equivalent SDOF model through the nonlinear time history response analysis is valid. The representative lateral displacement of a moment resisting reinforced concrete frames is close to the height of the first modal participation vector $_1$$\beta$$_1$u}=1. It can be found that the hysteresis rule of an equivalent SDOF model have influence on the time history response. Therefore, it is necessary for selecting hysteresis rules to consider hysteresis characteristics of a moment resisting reinforced concrete frames.

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Evaluation of a Fungal Spore Transportation in a Building under Uncertainty

  • Moon, Hyeun Jun
    • Architectural research
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    • v.8 no.1
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    • pp.37-45
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    • 2006
  • A fungal spore transportation model that accounts for the concentration of airborne indoor spores and the amount of spores deposited on interior surfaces has been developed by extending the current aerosol model. This model is intended to be used for a building with a mechanical ventilation system, and considers HVAC filter efficiency and ventilation rate. The model also includes a surface-cleaning efficiency and frequency that removes a portion of spores deposited on surfaces. The developed model predicts indoor fungal spore concentration and provides an indoor/outdoor ratio that may increase or decrease mold growth risks in real, in-use building cases. To get a more useful outcome from the model simulation, an uncertainty analysis has been conducted in a real building case. By including uncertainties associated with the parameters in the spore transportation model, the simulation results provide probable ranges of indoor concentration and indoor/outdoor ratio. This paper describes the uncertainty quantification of each parameter that is specific to fungal spores, and uncertainty propagation using an appropriate statistical technique. The outcome of the uncertainty analysis showed an agreement with the results from the field measurement with air sampling in a real building.

A Study on Developing an Evaluation Model for Criticizing the Model house of Multi-family Housing (공동주택 모델하우스 비평을 위한 평가모델 개발에 관한 연구)

  • 전경화;홍형옥;김정근
    • Proceedings of the Korean Institute of Interior Design Conference
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    • 1999.04a
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    • pp.133-136
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    • 1999
  • This study intends to develop an evaluation model which could be used as an effective tool for criticizing the model house of multi-family housing. The evaluation model has been developed based on the theoretical framework suggested by previous results of research related on hosing design, which comprises the following four components: 1) the paradigm of future home and life-style, 2) marketing effects of housing developer, 3) goals and principles of housing design, and 4) results of user-preference study. In this study, an evaluation model was suggested as a preliminary form which would be modified in detail after series of tests in the field. The evaluation model will be used provide standardized criteria for the quality of model houses, and eventually help to improve the quality of multi-family housing design by balanced information from theorist, user and developer.

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Development of CNN-Transformer Hybrid Model for Odor Analysis

  • Kyu-Ha Kim;Sang-Hyun Lee
    • International Journal of Advanced Culture Technology
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    • v.11 no.3
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    • pp.297-301
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    • 2023
  • The study identified the various causes of odor problems, the discomfort they cause, and the importance of the public health and environmental issues associated with them. To solve the odor problem, you must identify the cause and perform an accurate analysis. Therefore, we proposed a CNN-Transformer hybrid model (CTHM) that combines CNN and Transformer and evaluated its performance. It was evaluated using a dataset consisting of 120,000 odor samples, and experimental results showed that CTHM achieved an accuracy of 93.000%, a precision of 92.553%, a recall of 94.167%, an F1 score of 92.880%, and an RMSE of 0.276. Our results showed that CTHM was suitable for odor analysis and had excellent prediction performance. Utilization of this model is expected to help address odor problems and alleviate public health and environmental concerns.

Outlying Cell Identification Method Using Interaction Estimates of Log-linear Models

  • Hong, Chong Sun;Jung, Min Jung
    • Communications for Statistical Applications and Methods
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    • v.10 no.2
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    • pp.291-303
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    • 2003
  • This work is proposed an alternative identification method of outlying cell which is one of important issues in categorical data analysis. One finds that there is a strong relationship between the location of an outlying cell and the corresponding parameter estimates of the well-fitted log-linear model. Among parameters of log-linear model, an outlying cell is affected by interaction terms rather than main effect terms. Hence one could identify an outlying cell by investigating of parameter estimates in an appropriate log-linear model.

Object-Oriented Petri Net Model for Representation of Flexible Process Plan (유연공정계획 표현을 위한 객체지향형 페트리네트 모델)

  • Lee, Kyung-Huy
    • Journal of Korean Institute of Industrial Engineers
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    • v.23 no.4
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    • pp.669-686
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    • 1997
  • In this research, an object-oriented Petri net model for representing a flexible process plan is proposed, which is hierarchically multi-faceted for supporting planning, scheduling, and shop floor control functions. The multi-faceted process plan model consists of the following: a) an object model which represents on object-oriented data model, b) a static model which represents a process flow model with process alternatives, and c) a dynamic model which represents a process activity model with resources alternatives, of a flexible process plan. Petri nets allow the static and the dynamic process plan models to be represented in a unified formalism with an ease of model transformation. The multi-faceted process plan model suggested in this paper, is illustrated with a prismatic port in comprehensive detail.

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Effects of Mental Model and Intrinsic Motivation on Behavioral Intention of Smartphone Application Users

  • Jung, Wonjin;Yim, Hyung Rok
    • ETRI Journal
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    • v.38 no.3
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    • pp.589-598
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    • 2016
  • An application that has a simple user interface not only motivates a user to continue using the application, but also enables the user to develop their mental model for the application - the like of which is a product of their interaction with the application. In the information systems literature, little empirical research has been undertaken on the effects of the mental model and motivation on smartphone users' behavioral beliefs. Therefore, the aim of this study is to suggest a research model that can examine the following: 1) the effects that the mental model has not only on smartphone users' behavioral beliefs (that is, perceived usefulness and ease of use of an application) but also on their behavioral intention to use an application and 2) the effects that smartphone users' intrinsic motivation has on their behavioral beliefs through an expansion of the mental model. A survey is conducted, and structural equation modeling is then used to analyze the survey data. The results, through consideration of variables such as intrinsic motivation, perceived usefulness, perceived ease of use, and user satisfaction, indicate that the mental model has an indirect effect on a user's intention to use an application.