• The Korean Journal of Rheology
• /
• v.11 no.2
• /
• pp.159-167
• /
• 1999

Sandwich injection molding is one of the remarkable polymer processes recently developed from conventional injection molding. But it is almost impossible to do theoretical investigation that we've researched it through numerical simulation. In this paper, numerical simulation on the study of sandwich injection molding is based on Finite Element Method and FAN/Control Volume method. In addition to conventional filling parameter that can confirm skin polymer melt front, new filling parameters have been introduced to confirm core polymer melt front advancement. These filling parameters are defined in each layer which is divided to solve temperature field along the thickness direction. One can notice different filling patterns resulted from the variation of material properties such as viscosities and power-law indexes, and processing conditions such as switch-over times and wall temperatures. It gives us a better understanding of the sandwich injection molding process. And we can recognize that it's the core polymer spatial distribution after the completion of filling that is the most important key point to use this process for industrial molding process.

• Journal of Technology Innovation
• /
• v.14 no.1
• /
• pp.227-254
• /
• 2006

Under the recent trend of telecommunications and broadcasting convergence, much more various forms of new convergence broadcasting services are being introduced than ever before. Owing to the unique advantages, new convergence broadcasting services are expected to bring drastic changes to the current broadcasting service market. In this research, we attempt to examine what kind of attributes critically affect the competition among new convergence broadcasting services, and how much competitive they will be, based on the quantitative information about consumer preferences for the important attributes of new convergence broadcasting services. Conjoint survey was used in order to obtain stated preference data of consumers. From the results, some implications are obtained as follows. First, even though new convergence broadcasting services have many unique advantages, still price is the most important for the consumers. Second, it is expected that considerable consumer valuation exists for the unique advantages of new convergence broadcasting services like mobility and dual-way interactivity, which will add the competitiveness of those services in the future. Third, since midterm advertising puts negative utility on consumers, broadcasting services with midterm advertising will not be preferred to those with neither advertising nor midterm advertising. Fourth, service coverage and the number of consumers using the same broadcasting service have a significant feedback effect on the competition between broadcasting services from the dynamic aspect. Lastly, the consumer preference can be affected by demographic variables like age and gender, and broadcasting service usage patterns such as channel switchover for escaping advertisement and frequency of using other recorded media. Main findings of our research might become useful information for both telecommunication and broadcasting companies, contents providers, advertisers, and policy and regulation makers to cope with the uncertain environment of telecommunication and broadcasting convergence.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.20 no.9
• /
• pp.1710-1716
• /
• 2016

In general, software upgrade technique is needed to add new features or fix bug of software on a network devices. However, the problem is that the software must be upgraded after the termination of networking service to replace new package. An ISSU(In-Service Software Upgrade) technique is used to solve such the problem. ISSU is a technology to upgrade the software without interrupting the network service or an offline network equipment. In this paper, to provide a seamless networking service, we design and implement an architecture to apply ISSU technique to a network operating system. In this paper, we use high-availability feature in N2OS which has been developed by ETRI. In addition, in order to verify that the implemented ISSU function is operation properly, we proceed to test using a test environment based on a virtual machine.

• Journal of Digital Convergence
• /
• v.10 no.1
• /
• pp.29-38
• /
• 2012

As smart convergence occurs, solving the digital divide issue for weak layers such as the elderly, handicapped and poor groups is becoming an emerging issue. This study aims to promote information service to encourage active participation of the weak layers and to bridge the digital divide among those under the digital switchover and the smart phone convergence environments. This study, comparing the environments of Korea and other major countries with respect to digital divide, found some differences and tried to suggest proper policies for Korea to remain as a leading IT country. We expect this study to help the government, industries, schools cope with the divide issues and establish proper policies to provide weak layers with equal opportunities to IT in the coming smart convergence era.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.13 no.8
• /
• pp.1666-1672
• /
• 2009

Since wide display devices have recently become popular for communication activity, it is desirable for effective communication to share those displays in an efficient way. VNC(Virtual Network Computing) is a desktop sharing software, which transmits the desktop screen and the related events to other computers on different places. So, through VNC, it is possible for more than two users to share the same desktop screen at the same time. But it is very cumbersome to share wide display devices through the functions currently supported by VNC. In this paper, we describe the development of CoDisplay which is a VNC-based conference tool for efficient sharing of a wide display device. Conference participants connect to the wide display device through the associated network address, and transmit their desktop screen to the device. The control functions for the participants support the division of the display screen for multiple desktop screens and the switchover of desktop screens.

• The Journal of Korean Medicine
• /
• v.24 no.4
• /
• pp.92-101
• /
• 2003

Background ＆ Aims : The aim of this study was to investigate the change of dominant power with observation of gastric myoelectrical activity and its parameter linkage in electrogastrography. Methods : Electrogastrography was performed on a total of 123 subjects (113 patients with functional dyspepsia, 10 healthy controls) for 30 min in fasting state and 50 min in postprandial state. Average myoelectrical activity per frequency and accumulated electrical activity of 5 min duration in each bradygastria, normogastria, and tachygastria were measured at the moment of frequency switchover of slow wave. Assumed parameter linkages were also investigated among dominant frequency, ％ of normal regularity, and dominant power (or power ratio). Results : Average myoelectrical activity per frequency was highest in bradygastria (mean 1.10-1.47 Volt/s), next highest in normogastria (mean 0.50-0.82 Volt/s), and lowest in tachygastria (mean 0.44-0.47 Volt/s). Average accumulated myoelectrical activity was highest in normogastria (mean 114.90-126.29 Volt/ss), next highest in tachygastria (mean 71.02-90.00 Volt/ss), and lowest in bradygastria (mean 12.93-51.94 Volt/ss). Significance of parameter linkages were noted in dominant frequency (p< 0.01) and in ％ of normal regularity (p< 0.01), but not in dominant power in case of frequency shift from bradygastria to normogastria (p=0.376). Conclusion : Dominant power is not a parameter that reflects the gastric myoelectrical activity related with only gastric contraction. Bradygastric dominant power does not follow the inter-parameter linkage of electrogastrography for gastric motility assessment.

• Cartoon and Animation Studies
• /
• s.6
• /
• pp.91-115
• /
• 2002

Character industry in Korea has a history of less than 20 years by now, as it began in earnest at the end of the 1980s. Domestic character market is estimated to be around 1.2 trillion won occupying mere 0.01% of the world character market of 1,200 trillion won and less than 4% of the Japanese market, according to the according to the calculation made by Korea Animation Producers Association. Local character takes up only 5% of the domestic character market, necessitating the development of the local character and an increase in market share. It is painful to look at the current status of the local character market especially when compared with the huge world market. However, it might be and opportune moment for us to reverse the situation in our favor by a mental switchover. And we need to face up to the reality that the local character industry has many problems, and it is our duty to settle them. What then are the problems caused by the foreign character taking up 90% of the domestic market? Foreign character overwhelming the local market will bring about cultural dependency, emotional confusion, and financial loss caused by the payment of the royalties stemming from the intellectual property rights. The following is suggested as methods of settlement for such problems: 1. Development of character emotionally appealing to the Koreans 2. Development of long-lived character 3. Development of character firmly based on a good scenario 4. Thorough planning & marketing 5. Establishing an institution exclusively governing character business This study discussed the importance of developing long-lived character appealing not only to the Koreans but also to the whole world, that will meet the requirements as stated in 1 & 2 of above. For this purpose Chungmugong General Lee Soon-shin was chosen out of the Korean historical personages for further analysis, trying to rediscover the significance of the character development based on originality.

• 제어로봇시스템학회:학술대회논문집
• /
• 1994.10a
• /
• pp.477-482
• /
• 1994

As the need for switchover to FA and for rationalization increases in the industrial world, educational courses in schools are more and more taking up the subjects of electronic machines, mechatronics and systems, etc., subjects which are a fusion of the previous subjects of electricity, electronics and machines. At our junior college, a control engineering course was inaugurated in 1974 prior to any other schools that offered such courses. As automation progressed, the use of industrial robots spread rapidly. The year of 1980 is regarded as the first year that the use of industrial robots become widespread. Responding to the current requests, a one-year research course was added to the control engineering course in 1983. Moreover, a robot engineering course was newly established in 1984, in which mechatronics and industrial robotics were instructed intensively in high efficiency. As a teaching aid, an air robot system which was based particularly on the FMS model and possessed pattern recognition capabilities was completed in 1982. This system has been used since then as the nucleus for hands-on training with robots and systems. As more and more intelligent machines and artificial intelligence become widespread in industry, these subjects are taking on greater importance and greater sophistication in the education offered by this department. Educational institutions are seeking to provide facilities and curricula which will meet the technological needs of this age. Our college is not an institution at the graduate school level, but rather a school which is at the more practical junior college level. An outline of the facilities introduced at our school is presented and the results of utilizing it in industrial robot engineering education is reported.

• Journal of the Institute of Electronics Engineers of Korea TC
• /
• v.43 no.8 s.350
• /
• pp.25-34
• /
• 2006

In this paper DynaMoNET is suggested as a novel IPv6-based multi-homed mobile network architecture which is composed of nested mobile ad hoc networks dynamically coming together through wireless personal area networks. Each ad hoc network has a mobile router which may work as a root mobile router instead of fixed mobile routers in a DynaMoNET. A root mobile router provides the reliable Internet connectivity for the entire mobile network. This paper includes a innovative handover protocol for multi-homed mobile networks, network switchover algorithm considering multiple decision factors, root mobile router election process based on token-based algorithm fast root mobile router discovery algorithm and fault avoidance mechanism to support reliable Internet connectivity. Finally the system architecture of a mobile router is given in detail.

• Archives of design research
• /
• v.13 no.2
• /
• pp.33-44
• /
• 2000

Typography is the field be needed the most emotional and potential originality in the visual designers works. The design process introduced by aesthetic results is depended on a designers sensibility and originality. Accordingly this study includes more detail suggestions for mental switchover and developing whole area of sense and its education which make more sincere and easy communication of sentences in typographic and messages, removing fixed ideas, that are, prejudice and preconception, is one of big problems in making originality through the educational programs for experimental typography approaching with a new vision. Today, the change of typographic environment carried the substance and effectiveness of traditional typography be suspected and new ways are growing fast to escape from these traditional value. This study introduces some education programs such as Typortrait, Typeface, Typographic Essay, Kinetic Typography to realize the experimental typography to meet a new stream and social needs under the situation of exoplosive change and harmony fairly with proposition of coexisting of inspiration and technology, and finally expected to develop and promote typography experiment newly and to make educational section understand and confirm them.