• Title/Summary/Keyword: Uncertain Process

Search Result 335, Processing Time 0.022 seconds

The Current Conditions of the Operational Process of Public Design Project (공공디자인사업 수행 프로세스 현황연구)

  • Park, Su-Kyoung;Moon, Jeong-Min
    • Korean Institute of Interior Design Journal
    • /
    • v.22 no.6
    • /
    • pp.173-180
    • /
    • 2013
  • As a way to raise the brand value of each area and activate local industries, public design projects have been competitively made. Meanwhile, public design has the characteristics of having an uncertain number of users, people with different interests, and management of the design by an administrative organization. Such characteristics may be obstacles to the results of public design and finally can cause many problems in a project's results. However, although most local governments have executed public design projects, systematic research for them and organized execution of the projects has been insufficient. For successful realization, proper organization, and consistent public design, research on a strategic design process is needed. Therefore, this study investigated the current status of public design projects to understand problems in the design process and solve them. The results are presented as follows: First, the design process for public spaces has a dual structure including a specialized process of design development in its execution and management and the execution process in the planning state is unsatisfactory and the process of designer selection is not consistent. Second, as a result of investigating the current status of the design process for public spaces, it was deduced that as most of the projects have been subjectively and temporarily managed by wholly charged organizations without specialized consultation or investigation with different related departments, there have been diverse problems in securing design quality. Third, as a result of analysing the specific execution processes carefully, it was suggested that problems in the process can be solved by decisions through consultation and discussion. As well supportive consultation systems should be used actively.

A decision making framework model for the selection of a RP using hybrid multiple attribute decision making techniques (3차원 조형장비 선정을 위한 복합 다요소 의사결정 구조 모델 개발에 관한 연구)

  • Byun, Hong-Seok
    • Journal of the Korean Society of Manufacturing Process Engineers
    • /
    • v.7 no.3
    • /
    • pp.87-95
    • /
    • 2008
  • The purpose of this study is to provide a decision support to select an appropriate rapid prototyping(RP) machine that suits the application of a part. Selection factors include concept model, form/fit/functional model, pattern model for molding, material property, build time and part cost that greatly affect the performance of RP machines. However, the selection of a RP is not an easy decision because they are uncertain and vague. For this reason, the aim of this research is to propose hybrid multiple attribute decision making approaches to effectively evaluate RP machines. In addition, because subjective considerations are relevant to selection decision, a fuzzy logic approach is adopted. The proposed selection procedure consists of several steps. First, we identify RP machines that the users consider. After constructing the evaluation criteria, we calculate the weights of the criteria by applying the fuzzy Analytic Hierarchy Process(AHP) method. Finally, we construct the fuzzy Technique of Order Preference by Similarity to Ideal Solution(TOPSIS) method to achieve the ranking order of all machines providing the decision information for the selection of RP machines.

  • PDF

A Study on Real Time Working Path Control of Vertical Type Robot System for the Forging and Casting Process Automation

  • Lim, O-Deuk;Kim, Min-Seong;Jung, Yang-Geun;Kang, Jung-Suk;Won, Jong-Bum;Han, Sung-Hyun
    • Journal of the Korean Society of Industry Convergence
    • /
    • v.20 no.3
    • /
    • pp.245-256
    • /
    • 2017
  • In this study, we describe a new approach to real-time implementation of working path control for the forging and casting manufacturing process by vertical type articulated robot system. The proposed control scheme is simple in structure, fast in computation, and useful for real-time control of factory automation based on robot system. Moreover, this scheme does not require any accurate parameter information, nor values of the uncertain parameters and payload variations. Reliability of the proposed controller is proved by simulation and experimental results for robot manipulator consisting of arm with six degrees of freedom under the variation of payloads and tracking trajectories in Cartesian space and joint space. The vertical type articulated robot manipulator with six axes made in SMEC Co., Ltd. has been used for real-time implementation test to illustrate the enhanced working path control performance for unmanned automation of the forging and casting manufacturing process.

Economic Analysis of Power Transmission Lines using Interval Mathematics

  • Teegala, Srinivasa Kishore;Singal, Sunil Kumar
    • Journal of Electrical Engineering and Technology
    • /
    • v.10 no.4
    • /
    • pp.1471-1479
    • /
    • 2015
  • A major portion of the capital costs in the present day power transmission systems are due to the cost of equipment and construction process. Transmission utilities in the recent years are drawing greater attention towards performing life cycle costing studies for cost management and decision making. However, the data involved in these studies are highly uncertain and the effect of these uncertainties cannot be directly included in the study process, resulting in inaccurate solutions. Interval mathematics provides a method for including these uncertainties throughout the cost analysis and provides final solution range in the form of intervals. In this regard, it is essential and extremely important that significant research has to be carried out in understanding the principles of life cycle costing methodology and its applicability to cost analysis of transmission lines along with uncertainties involved in the cost assessment process. In this paper, economic analysis of power transmission lines using interval mathematics has been studied. Life cycle costing studies are performed using net present value analysis on a range transmission lines used in India and the results are analyzed. A cost break even analysis considering right of way costs was carried out to determine the point of economy indifference.

Numerical and experimental study for Datong coal gasification in entrained flow coal gasifier

  • Park, Y. C.;Park, T. J.;Kim, J. H.;Lee, J. G.
    • Proceedings of the Korea Society for Energy Engineering kosee Conference
    • /
    • 2001.11a
    • /
    • pp.69-76
    • /
    • 2001
  • The coal gasification process of a slurry feed type, entrained-flow coal gasifier was numerically predicted in this paper. By divding the complicated coal gasification process into several simplified stages suh as slurry evaporation, coal devolitilisation and two-phase reactions coupled with turbulent flow and two-phase heat transfer, a comprehensive numerical model was constructed to simulate the coal gasification process. The k-$\varepsilon$turbulence model was used for the gas phase flow while the Random-trajectory model was applied to describe the behavior of the coal slurry particles. The unreacted-core shrinking model and modified Eddy Break-Up(EBU) model were used to simulate the heterogeneous and homogeneous reactions, respectively. The simulation results obtained the detailed informations about the flow field, temperature inside the gasifier. Meanwhile, the simulation results were compared with the experimental data as function of $O_2$/coal ratio. It illustrated that the calculated carbon conversions agreed with the measured ones and that the measurd quality of the atngas was better than the calculated one when the $O_2$/coal ratio increases. The result was related with the total heat loss through the gasifier and uncertain kinetics for the heterogeneous reactions.

  • PDF

A Study of the Effective Method for Collecting and Analyzing Human Sensibility Applied Fuzzy Set Theory (퍼지이론을 응용한 효율적 감성 수집과 분석에 관한 연구)

  • Baek, Seung-Ryeol;Park, Beom
    • Journal of the Ergonomics Society of Korea
    • /
    • v.17 no.1
    • /
    • pp.47-54
    • /
    • 1998
  • Product design and development is very important process in enterprise activities. Reducing development time and reflecting consumer's needs is required to product design and development for increasing benefit and decreasing cost. Human sensibility ergonomics is one of the important technology of R&D in product development. However, the subjective method of human sensibility ergonomics has several problems to analyze and to Quantify experimental data and objective method of human sensibility ergonomics is still in process on study. In this research, new analyzing method is proposed for the subjective human sensibility ergonomics applied with fuzzy set theory. What is the useful theory for controlling uncertain type of information like human mind? This approach is more effective method for analyzing consumer's needs for product design and development process. At collecting needs, certainty scale is added for adapting hedge of fuzzy function. Using a kind of union operator, synthesize each item to analyze identification of each item with fuzzy hamming distance. Identification of analysis is classified with the relational weight using Relationship Chart Method, and is drawn the relationship diagram for clustering each item. A case study with sample test is conducted and demonstrated with this suggested method for more effective way.

  • PDF

Stochastic modelling and lifecycle performance assessment of bond strength of corroded reinforcement in concrete

  • Chen, Hua-Peng;Nepal, Jaya
    • Structural Engineering and Mechanics
    • /
    • v.54 no.2
    • /
    • pp.319-336
    • /
    • 2015
  • Life cycle performance of corrosion affected RC structures is an important and challenging issue for effective infrastructure management. The accurate condition assessment of corroded RC structures mainly depends on the effective evaluation of deterioration occurring in the structures. Structural performance deterioration caused by reinforcement corrosion is a complex phenomenon which is generally uncertain and non-decreasing. Therefore, a stochastic modelling such as the gamma process can be an effective tool to consider the temporal uncertainty associated with performance deterioration. This paper presents a time-dependent reliability analysis of corrosion affected RC structures associated bond strength degradation. Initially, an analytical model to evaluate cracking in the concrete cover and the associated loss of bond between the corroded steel and the surrounding cracked concrete is developed. The analytical results of cover surface cracking and bond strength deterioration are examined by experimental data available. Then the verified analytical results are used for the stochastic deterioration modelling, presented here as gamma process. The application of the proposed approach is illustrated with a numerical example. The results from the illustrative example show that the proposed approach is capable of assessing performance of the bond strength of concrete structures affected by reinforcement corrosion during their lifecycle.

Prediction of duration and construction cost of road tunnels using Gaussian process regression

  • Mahmoodzadeh, Arsalan;Mohammadi, Mokhtar;Abdulhamid, Sazan Nariman;Ibrahim, Hawkar Hashim;Ali, Hunar Farid Hama;Nejati, Hamid Reza;Rashidi, Shima
    • Geomechanics and Engineering
    • /
    • v.28 no.1
    • /
    • pp.65-75
    • /
    • 2022
  • Time and cost of construction are key factors in decision-making during a tunnel project's planning and design phase. Estimations of time and cost of tunnel construction projects are subject to significant uncertainties caused by uncertain geotechnical and geological conditions. The Gaussian Process Regression (GPR) technique for predicting ground condition and construction time and cost of mountain tunnel projects is used in this work. The GPR model is trained with data from past mountain tunnel projects. The model is applied to a case study in which the predicted time and cost of tunnel construction using the GPR model are compared with the actual construction time and cost for model validation and reducing the uncertainty for the future projects. In addition, the results obtained from the GPR have been compared with to other models of artificial neural network (ANN) and support vector regression (SVR) that the GPR model provides more accurate results.

Managing Service Recovery via Social Media: The Impact of Transparency and Service Recovery Type in the Distribution of Feedback

  • Jie CAI;Yoonseo PARK
    • Journal of Distribution Science
    • /
    • v.22 no.1
    • /
    • pp.79-94
    • /
    • 2024
  • Purpose: The popularity of social media has altered how customers interact with businesses, and an increasing number of customers prefer to voice their complaints on social media. Bystanders can observe the customer complaint process on social media, but the impact of transparency on bystanders remains uncertain. Therefore, this study established and verified a model for defining the effect of transparency and service recovery types on bystanders. Research Design and Methodology: In this study, we used the internet survey platform "So Jump" to collect data. And we validated three studies with SPSS 26.0 and Smart PLS 4.0. Result: First, we showed that the transparency process (vs. result) is more likely to increase customer forgiveness and E-loyalty and reduce E-NWOM intention among bystanders. Second, customer forgiveness also plays a complementary mediating role between transparency and E-loyalty, as well as between transparency and E-NWOM intention. Finally, we found a modest interaction effect between transparency (process vs. result) and service recovery types (psychological vs. tangible vs. hybrid) on bystanders' customer forgiveness and E-loyalty. Conclusions: This study provides actionable recommendations for how service managers can effectively employ social media as a means for distributing feedback information to manage service recovery in the future.

DTN Routing for Improving Transmission Efficiency in a Destroyed Environment of Communication Infrastructure (통신 인프라가 파괴된 환경에서 전송 효율 향상을 위한 DTN 라우팅)

  • Jang, Sung-Jin;Lee, Won-Hui
    • The Journal of the Institute of Internet, Broadcasting and Communication
    • /
    • v.20 no.3
    • /
    • pp.37-41
    • /
    • 2020
  • In this paper, we propose a routing method to improve the message transmission efficiency between DTN nodes in an environment where communication infrastructure in the city is destroyed. In the situation where a certain size of communication infrastructure can not function, the message transmission process between the nodes is explained. An effective routing method for improving reliability between nodes was proposed and evaluated using DTN simulator. The routing algorithm with improved reliability in urban areas was confirmed by simulation considering the message transmission relationship between nodes on uncertain path due to the destruction of communication infrastructure. We used a routing algorithm that includes all the contact information the node has experienced in the past. In the simulation of delivering messages in a situation where the communication infrastructure was destroyed, relatively better results were obtained than the existing routing algorithm.