• International Journal of CAD/CAM
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• v.2 no.1
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• pp.29-37
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• 2002

De-manufacturing is an entire process of collecting, disassembling, reusing, refurbishing, recycling, and/or disposing products that are obsolete or un-repairable. Designing the products for inexpensive and efficient disassembly enhances the ease of de-manufacturing. Virtual disassembly addresses the difficulty and the methods to disassemble a product in design stage rather than really disassemble a product at the end of its life cycle. Based on the virtual disassembly analysis results, design will be improved for better assembling/disassembling. This paper presents a systematic virtual disassembly methodology such as disassembly relation modeling, path/sequence automatic generation and evaluation. This paper also presents a new virtual disassembly interface paradigm via virtual reality technology for disassembly simulation in virtual environment.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.18 no.12
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• pp.2911-2918
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• 2014

Nowadays, most Internet servers run on virtual a network which connects each virtual machine, to process large amounts of data on single physical computer. The virtual machines for their own purposes are interconnected to other virtual server systems with various types of operating systems. Each virtual server may share one physical computer resources and operates at a service seamlessly to each other. Sometimes even the virtual machines are implemented using a method that lease the physical IT resources without purchasing physical server. Therefore, a virtual switch is needed to improve the performance when a large number of virtual machines operate on physical server. In this study, the implementation and investigation was performed for the virtual switches, OpenvSwitch and DPDKvSwitch, in order to provide the necessary high-performance cloud services to creative business.

• International Journal of Computer Science & Network Security
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• v.22 no.4
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• pp.147-158
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• 2022

Cloud Computing offers flexible, on demand, ubiquitous resources for cloud users. Cloud users are provided computing resources in a virtualized environment. In order to meet the growing demands for computing resources, data centres contain a large number of physical machines accommodating multiple virtual machines. However, cloud data centres cannot utilize their computing resources to their total capacity. Several policies have been proposed for improving energy proficiency and computing resource utilization in cloud data centres. Virtual machine placement is an effective method involving efficient mapping of virtual machines to physical machines. However, the availability of many physical machines accommodating multiple virtual machines in a data centre has made the virtual machine placement problem a non deterministic polynomial time hard (NP hard) problem. Metaheuristic algorithms have been widely used to solve the NP hard problems of multiple and conflicting objectives, such as the virtual machine placement problem. In this context, we presented essential concepts regarding virtual machine placement and objective functions for optimizing different parameters. This paper provides a taxonomy of metaheuristic algorithms for the virtual machine placement method. It is followed by a review of prominent research of virtual machine placement methods using meta heuristic algorithms and comparing them. Finally, this paper provides a conclusion and future research directions in virtual machine placement of cloud computing.

• Korean Journal of Computational Design and Engineering
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• v.15 no.5
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• pp.343-353
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• 2010

Time to market and cost-efficient production are some of the challenge that manufacturing industries face. Modern methods of engineering can't help such organizations attain competitive advantage. To help these situations, MEMPHIS (Middleware for Exchanging Machinery and Product Data in Highly Immersive Systems) was introduced as an approach that enables VE (Virtual Engineering) and links engineering applications with VR (Virtual Reality) solutions. Thus an environment is provided to implement virtual design reviews and enable the application of virtual prototyping methods. However MEMPHIS could just handle Product data for virtual design review and simulation. In this paper, we newly define and develop the extended MEMPHIS that enables virtual manufacturing with Process, Resource and Plant data as well as Product data.

• Archives of design research
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• v.14 no.4
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• pp.167-177
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• 2001

• Asia pacific journal of information systems
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• v.22 no.2
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• pp.39-69
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• 2012

With the advent of communication technologies including electronic collaborative tools and conferencing systems provided over the Internet, virtual collaboration is becoming increasingly common in organizations. Virtual collaboration refers to an environment in which the people working together are interdependent in their tasks, share responsibility for outcomes, are geographically dispersed, and rely on mediated rather than face-to face, communication to produce an outcome. Research suggests that new sets of individual skill, knowledge, and ability (SKAs) are required to perform effectively in today's virtualized workplace, which is labeled as individual virtual competence. It is also argued that use of online social networking sites may influence not only individuals' daily lives but also their capability to manage their work-related relationships in organizations, which in turn leads to better performance. The existing research regarding (1) the relationship between virtual competence and task performance and (2) the relationship between online networking and task performance has been conducted based on different theoretical perspectives so that little is known about how online social networking and virtual competence interplay to predict individuals' task performance. To fill this gap, this study raises the following research questions: (1) What is the individual virtual competence required for better adjustment to the virtual collaboration environment? (2) How does online networking via diverse social network service sites influence individuals' task performance in organizations? (3) How do the joint effects of individual virtual competence and online networking influence task performance? To address these research questions, we first draw on the prior literature and derive four dimensions of individual virtual competence that are related with an individual's self-concept, knowledge and ability. Computer self-efficacy is defined as the extent to which an individual beliefs in his or her ability to use computer technology broadly. Remotework self-efficacy is defined as the extent to which an individual beliefs in his or her ability to work and perform joint tasks with others in virtual settings. Virtual media skill is defined as the degree of confidence of individuals to function in their work role without face-to-face interactions. Virtual social skill is an individual's skill level in using technologies to communicate in virtual settings to their full potential. It should be noted that the concept of virtual social skill is different from the self-efficacy and captures an individual's cognition-based ability to build social relationships with others in virtual settings. Next, we discuss how online networking influences both individual virtual competence and task performance based on the social network theory and the social learning theory. We argue that online networking may enhance individuals' capability in expanding their social networks with low costs. We also argue that online networking may enable individuals to learn the necessary skills regarding how they use technological functions, communicate with others, and share information and make social relations using the technical functions provided by electronic media, consequently increasing individual virtual competence. To examine the relationships among online networking, virtual competence, and task performance, we developed research models (the mediation, interaction, and additive models, respectively) by integrating the social network theory and the social learning theory. Using data from 112 employees of a virtualized company, we tested the proposed research models. The results of analysis partly support the mediation model in that online social networking positively influences individuals' computer self-efficacy, virtual social skill, and virtual media skill, which are key predictors of individuals' task performance. Furthermore, the results of the analysis partly support the interaction model in that the level of remotework self-efficacy moderates the relationship between online social networking and task performance. The results paint a picture of people adjusting to virtual collaboration that constrains and enables their task performance. This study contributes to research and practice. First, we suggest a shift of research focus to the individual level when examining virtual phenomena and theorize that online social networking can enhance individual virtual competence in some aspects. Second, we replicate and advance the prior competence literature by linking each component of virtual competence and objective task performance. The results of this study provide useful insights into how human resource responsibilities assess employees' weakness and strength when they organize virtualized groups or projects. Furthermore, it provides managers with insights into the kinds of development or training programs that they can engage in with their employees to advance their ability to undertake virtual work.

• Journal of the Korean housing association
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• v.20 no.1
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• pp.91-99
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• 2009

With the development of the internet and the spread of 'digital home', apartment houses equipped with the homepages connecting apartment houses as one cyberspace unit have increased. The virtual community with a homepage in apartment complex have improved the effect on management businesses in the side of a apartment manager and increased the importance of the space with a strong tie between residents in the side of residents. But the apartment residents didn't make full use of the virtual community because they have the low level of recognition of it. Therefore, this study attempted to present basic materials for the scheme to revitalize the virtual community. For this purpose, it attempted to find residents' recognition of and participation in the virtual community and demand for the classified contents conducted before this study. In the research method, it conducted the questionnaire research. The results are as follows. 1) First of all, It was found that the apartment residents had the low level of recognition of the virtual community. There was a significant difference according to the degree and the level of using the internet. Some easy-access programs are necessary. 2) The apartment residents took part in the virtual community about 67 percents because there was a lack of the public relation of the virtual community. 3) It was found that there was a significant positive correlation between the level of recognition and participation. 4) An attempt was made to identify the apartment residents' demand for the type of virtual community contents. It was found that most of contents were needed. 'apartment complex introduction and management information' showed the highest score among them. 5) Most respondents are affirmative to the virtual community. Therefore the residential community could be reinforced if the contents of virtual community is developed and well operated in the future.

• Fashion & Textile Research Journal
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• v.25 no.5
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• pp.593-602
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• 2023

This study aimed to facilitate the use of virtual technologies such as sewing, appearance, and material expression in 3D virtual wear programs. For product production and education, we expounded how to express the shoulder shape and silhouette of sleeve-expanded power shoulder jackets. Two designs of sleeve-expanded power shoulder jackets were selected, and virtual jackets were produced using a virtual avatar based on the body dimensions of female subjects in their 20s. The essential purpose of a 3D virtual power shoulder jacket is to express the shoulder angle rise and shoulder width, which are much wider than the avatar's shoulder. Therefore, the virtual pad values were adjusted for the collision and rendering of each thickness. In addition, the position and angle of the virtual pads were controlled through simulation. Appearance similarity was evaluated using photographic data and the virtual jackets. For the set-in sleeve virtual power shoulder jacket, the wrinkle expressions of the torso and sleeve were rated as moderate, and material expression was slightly insufficient. The similarity of some ease and width items of the torso was tightly expressed, and the overall appearance, positions of lines, and details of jackets were rated high, especially at the neck and sleeve shapes. In the case of the kimono virtual power shoulder jacket, the expressions of the torso wrinkles and buttons were slightly lower; however, the overall similarity, basic lines, ease, shoulder and neck details, and material expression of the virtual jackets were highly evaluated.

• The Journal of Information Systems
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• v.27 no.3
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• pp.43-62
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• 2018

Purpose Since the Bitcoin, which was the first virtual currency, was made at 2009, almost 1,000 virtual currencies appeared onstage in the world. Even though virtual currencies have the function of money as a medium of exchange or contract, any of those has not yet entered the commercialization stage. Instead, some of the virtual currencies show the nature of investment assets. In the case of virtual money investment, users tend to use all the information of the world because information transfer is very easy and capital movement is almost free between different countries. In addition, as the transaction sizes of virtual currencies increase, a virtual currency price is no longer independent and is likely to be affected by the prices of other virtual currencies. Therefore, it is necessary to understand the influence among virtual currency markets, which helps successful implementation of investment strategies. Design/methodology/approach This study focuses on the investment product function of virtual money and conducts the analysis using the time series model used in the financial and economic areas. In this paper, we try to analyze the return and volatility transfer effect of virtual money markets through GJR-GARCH model. Findings This study is expected to find out whether we can make market forecasts through reflecting changes in other markets. In addition, we can reduce the trial and error of user decision making by using the information on the yield and volatility transition effect derived from the research results, and it is expected to reduce the opportunity cost of users.

• Korean Journal of Computational Design and Engineering
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• v.9 no.2
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• pp.148-157
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• 2004

Interactive simulators that simulate mechanical systems are being developed for the purpose of performance evaluation of product design, replacement of physical training, and entertainment game. Use of flight simulator is increasing to reduce risk and cost of physical training, and we need virtual environment which covers large area terrain. We need a method that can reduce development cost and construction time of virtual environment that simulate the real environment. There have been attempts to link GIS or remote sensing field with virtual reality. This paper examines a method that helps to construct virtual environment, and attempts to link geographic information with virtual reality. A construction method of virtual environment based on digital map and satellite image has been studied.