• Journal of the Korean Institute of Navigation
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• v.25 no.1
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• pp.1-9
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• 2001

It is well known that, especially in the case of full-bodied ship, the course stability may become the severest among 4 items of requirement in Interim Standards for Ship Manoeuvrability adopted by IMO in 1993. The purpose of this study is to find some ideas for characteristics of fluid flow pattern around ship's stern in manoeuvring motion with parameter of changes in rudder size. We carried out two kinds of model experiment in obliquely running condition at circulating water channel. One is measurement on straightening effect of incoming flow to rudder and the other is experiment on flow visualization around the gap between rudder and stern-bottom. We discuss the correlation between the flow characteristics around ship's stem and flow straightening effect at rudder from the viewpoint of course stability. As a result, it is clarified that the gap between rudder and stern-bottom plays an important role in course stability of full-bodied ship. It is pointed out that there is quite a possibility of bad course stability as the gap between rudder and stern-bottom decreases.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.13 no.6
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• pp.1128-1140
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• 2009

In this paper, we present a patient real-time vital sign information transmission system to effectively support developing real-time communication service by using a real-time object model named TMO (Time-Triggered Message-Triggered Object). Also, we describe the application environment as the ICU(Intensive Care Unit) to guarantee real-time service message with TMO structure in distributed network systems. We have to design to obtain useful vital sign information, which is generated at parsing data receiver modulor of HIS with TMO structure, that is offered by the central monitor. Vital sign informations of central monitor is composed of the raw data of several bedsite patient monitors. We are willing to maintain vital sign information of real time and continuity that is generated from the bedsite patient monitor. It is able to apply to remote medical examination and treatment. we proposed integration method between a vital sign database systems and hospital information systems. In the real time simulation techniques based on TMO object modeling, We have observed several advantages to the TMO structuring scheme. TMO object modeling has a strong traceability between requirement specification and design.

• Korean Journal of Construction Engineering and Management
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• v.3 no.1 s.9
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• pp.91-96
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• 2002

The purpose of this study is to present a systemized flow of temporary facility(TF) planning information. The current TF planning tends to be established by subjective decision making of field workers. Therefore TF planning needs more systemized information flow to provide a reliable schedule. The study was implemented through interview with experts for reliable TF planning. The main contents of the study are as follows; 1) TF planning process model(IDEF0) are established. 2) Various information flow diagrams proposed to support TF planning decision-making. The study recommends that, as a future research, the computer system be developed for application of the information flow.

• Korean Journal of Construction Engineering and Management
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• v.5 no.3 s.19
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• pp.88-96
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• 2004

Recently, client requirements concept is an important issue related to many effects of firms. Especially, if we think that apartment is given a great deal of national construction industry, it is requested that we should try to improve apartment quality with various methods of client requirements survey and reflecting those on apartment project. The technique searching and applying client requirements to apartment project is requested for that and ROQ(Return On Quality) process connected to QFD(Quality Function Deployment) is a technique which is used in manufacturing industry and help to make money by rising client satisfaction with searching clients requirements, and applying this to quality improvement program. In this study apartment quality management development is suggested through using ROQ process. For this customer interview research and FGI(Focus Group Interview) was carried out and clients requirement was analyzed with this. Then quality improvement program applicable to developing a new apartment product was established with specialist monitoring. A new apartment quality management development plan is prosed with this process.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.11A
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• pp.1051-1058
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• 2010

Mobile IP (MIP) and SIP are considered as important technologies to provide the macro mobility in the next generation mobile convergence networks which have heterogeneous access networks. Typically, MIP and SIP are more suitable for the non-real-time TCP connections and the real-time RTP/UDP sessions respectively, hence a handset which uses both of these sessions should simultaneously apply MIP and SIP to perform the efficient mobility management. Existing multi-layered mobility management schemes focus on the signalling order of each protocol. However, simple combining of two protocols cannot provide the performance enhancement of the mobility management. In this paper, a novel multi-layered mobility management algorithm using the combination of SIP and fast MIPv6 (FMIPv6) is proposed. FMIPv6 and SIP mobility is simultaneously performed to reduce the service interrupt time and to guarantee QoS requirement. The delay model is defined to analysis the performance of the algorithm and the simulation results show the performance of the proposed algorithm.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.7
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• pp.1003-1010
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• 2005

A study consisting of 3 trials was designed to assess the relative biological efficacy of DL-methionine (DL-Met) in comparison to liquid methionine hydroxy analogue (MHA-FA) in growing pigs. In trial I a basal diet was supplemented with three graded levels of DL-methionine (0.25, 0.50 and 0.75 g/kg) or liquid MHA-FA (0.0285, 0.0570 and 0.0855 g/kg) on equimolar basis. The basal diet contained 18.3% CP, 0.22% Met and 0.51% Met+Cys, which is below the methionine requirement for weaned pigs between 10 and 20 kg BW according to NRC (1998) but adequate in all other essential nutrients and energy. Using an exponential model, the efficacy of the two methionine sources was estimated from nitrogen retention data obtained in 42 piglets with an initial BW between 11.0 kg (Exp. 1) and 11.7 kg (Exp. 2). In trials II and III, with a total of 192 and 96 pigs, and with an initial BW of 10.6 and 21 kg, respectively, growth response criteria were assessed to determine if in agreement with previous studies in pigs and poultry a biological effectiveness of about 65% on average could be confirmed for liquid MHA-FA in comparison to DL-met. Based on N-retention (trial I) the biological efficacy of liquid MHA-FA on a weight-to-weight basis was calculated to be 62% relative to DL-met. Basically, these results were confirmed using growth response criteria as measures; the results of trial II and III revealed no significant differences in growth performance and feed conversion between treatments indicating that 100 parts of liquid MHA-FA can be replaced by 65 parts of DL-met.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.9 no.11
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• pp.4268-4290
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• 2015

Future mobile communications face enormous challenges as traditional voice services are replaced with increasing mobile multimedia and data services. To address the vast data traffic volume and the requirement of user Quality of Experience (QoE) in the next generation mobile networks, it is imperative to develop efficient content distribution technique, aiming at significantly reducing redundant data transmissions and improving content delivery performance. On the other hand, in recent years cloud computing as a promising new content-centric paradigm is exploited to fulfil the multimedia requirements by provisioning data and computing resources on demand. In this paper, we propose a cooperative caching framework which implements State based Content Distribution (SCD) algorithm for future mobile networks. In our proposed framework, cloud service providers deploy a plurality of cloudlets in the network forming a Distributed Cloud Service Network (DCSN), and pre-allocate content services in local cloudlets to avoid redundant content transmissions. We use content popularity and content state which is determined by content requests, editorial updates and new arrivals to formulate a content distribution optimization model. Data contents are deployed in local cloudlets according to the optimal solution to achieve the lowest average content delivery latency. We use simulation experiments to validate the effectiveness of our proposed framework. Numerical results show that the proposed framework can significantly improve content cache hit rate, reduce content delivery latency and outbound traffic volume in comparison with known existing caching strategies.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.40 no.4
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• pp.364-374
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• 2012

The purpose of this study is to perform the reliability-corrected development cost estimation of the launch vehicle at the conceptual design phase. In order to estimate the launch vehicle development cost, the estimation method based on the independent variable such as the rocket performance and dry mass has been mainly implemented up to now. This approach has made the approximate cost estimation possible, however, the cost variation according to the reliability requirement could not be reflected. In this paper, the cost estimation methodology that introduces the reliability factor in addition to the performance and mass in the TRANSCOST model is presented in order to improve the limitation of current cost estimation method. The development cost of KSLV(Korea Space Launch Vehicle)-II is estimated on the basis of this newly implemented concept with reliability as an added parameter.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.40 no.4
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• pp.300-308
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• 2012

In GPS/INS/barometer navigation system for UAV, two procedures were proposed in order to set three reference parameters for the pressure altitude of QNH or QFE settings, using the navigation data from on-board system alone. These procedures yield required the reference parameters through mathematical process with the altitude and the atmosphere properties measured for a short duration of flight, of which a special pattern is requested according to the selected procedure. Dependency only upon the on-board navigation data can eliminate a requirement for the atmospheric measurement system in the ground support system and can expand a flight boundary to a remote area where the ground support is not available. Especially the procedure with the regression method uses altitude and pressure but temperature to produce the three reference parameters. No need of temperature measurement for the pressure altitude system can simplify the on-board air data system.

• Journal of Korea Spatial Information System Society
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• v.3 no.1 s.5
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• pp.95-108
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• 2001

The provision of spatial data is a key infrastructural requirement for the promotion of economic growth, environmental quality, social progress, etc. 4S technology integrates 4 kinds of systems that process spatial data: GIS (Geographic Information System), GNSS (Global Navigation Satellite System), ITS (Intelligent Transport System), and SIIS (Spatial Imagery Information System). Spatial data processing field is expected to get synergy effect and overcomes development limit of individual unit technology via 4S technology. This paper discusses both the development of 4S-kernel technology and the construction of 4S-based framework, In the development of 4S kernel technology, we will concentrate on the following issues: the development of 4S base components for reciprocity integration among GIS, SIIS, GNSS and ITS technologies, the development of 4S-Mobile S/W and H/W, 4S-Van components, and national LBS technologies. And in the construction of 4S-based framework, we will especially concentrate on the ISP for overall 4S technologies, the international cooperative research center, and the guide model deduction for supervision and certification of 4S projects. Finally, we examine about how the construction of 4S-baed framework affects 4S industry.