• Proceedings of the Korean Institute of Navigation and Port Research Conference
• /
• 2010.04a
• /
• pp.139-142
• /
• 2010

ENC(Electronic Navigational Chart) is an electronic chart that digitize nautical chart including all kinds of information of nautical chart. Mariners have difficulty reading information because of clutter problem if display scale of ECDIS is lower than compilation scale of ENCs. IHO made SCAMIN improvement model included in S-65 Standard to settle this ENC clutter problem. This SCAMIN model includes both simple restriction that should safety some requirement and share geographic information. and hard restriction that should overlap with area object such as depth area, land area, dredge area. It also apply SCAMIN step of sounding value according to importance of safety navigation. In this paper, we analyzed the restrictions for SCAMIN model of S-65 Standard, developed algorithm and application to apply theses restrictions reasonably and mechanically. Also we applied this algorithm and application to Korea ENCs and evaluated the result of performance.

• International Journal of Highway Engineering
• /
• v.11 no.2
• /
• pp.175-184
• /
• 2009

The study analyzes likely impacts of left truck lane restriction strategies on urban freeways based on a traffic simulation model. This study contains two main parts. The first part is performed to develop feasible alternatives as well as provide insights into conditions under left truck lane restrictions would be effective based on the analysis of two representative hypothetical highways. Different levels of O-D demands and truck percentage is at least restrictions would work when maximum rate of flow is more than 1,300vphpl or truck percentage is at least over loft of the total traffic. The second part of our study concerns a case study on a region with perhaps the highest truck volumes in the U.S. - a northbound section of Interstate 710 corridor in Los Angeles County, Southern California. The results show that restricting the two leftmost lanes under congested traffic with heavy ruck use, provides the most positive impacts in terms of improving the flow of traffic and saving fuel. In addition, our study demonstrates that in general, the number of lanes restricted is a crucial factor in the success of this strategy.

• Journal of Advanced Research in Ocean Engineering
• /
• v.3 no.1
• /
• pp.41-52
• /
• 2017

This paper presents a numerical and experimental study of sloshing loads on liquefied natural gas (LNG) vessels. Conventional LNG carriers with membrane-type cargo systems have filling restrictions from 10% to 70% of tank height. The main reason for such restrictions is high sloshing loads around these filling depths. However, intermediate filling depths cannot be avoided for most LNG vessels except the LNG carrier. This study attempted to design a membrane-type LNG tank with a modified lower-chamfer shape that allows all filling operations. First, numerical sloshing analysis was carried out to find an efficient height of the lower-chamfer that can reduce sloshing pressure at partially filled conditions. The numerical sloshing analysis program SHI-SLOSH was used for numerical simulation; this program is based on SOLA-VOF. The effectiveness of the newly designed tanks was validated by 1:50-scale three-dimensional tank tests. A total of three different tanks were tested: a conventional tank and two modified tanks. As test conditions, various filling depths and wave periods were considered, and the same test conditions were applied to the three tanks. During the test, slosh-induced dynamic pressures were measured around the corners of the tank wall. The measured pressure data were post-processed and the pressures of the three different tanks were statistically compared in several ways. Experimental results show that the modified tanks were quite effective in reducing sloshing loads at low filling conditions. This study demonstrated the possibility of all filling operations for LNG cargo containment systems.

• Health Policy and Management
• /
• v.13 no.3
• /
• pp.1-20
• /
• 2003

The purpose of this study was to investigate the current status of health promotion policies about antismoking, and the relationship between policy status, enforcement of smoking restrictions and perceptions of smoking behaviour among teachers. A representative sample of 173 teachers$.$school inspectors from 150 elementary$.$middle$.$high schools in Gangwon-do was surveyed during Gangwon-do Office of Education's antismoking and temperance training course in 2002 (response rate 60.7%). One staff member from each school was also analyzed regarding school antismoking polices for students and teachers in several locations within and outside the school building. The results showed that 118 elementary$.$middle$.$high schools (78.7%) had an antismoking policy and more schools had a written policy on student antismoking than on teacher antismoking. Most schools (92.4%) in the sample banned smoking by students, but 52 schools (44.1%) allowed smoking by teachers in restricted areas. However, teachers reported seeing smoking sometimes in the toilets (42.7%) or the playground (40.0%) among students and sometimes in the staff room (31.3%) or about every day on school premises (52.7%) among teachers. Irrespective of the type of policy or restrictions on smoking, the association between having a ban on student/teacher smoking and teachers' perceptions of student/teacher smoking in school was not significant. In conclusion, we suggest that most schools must have explicitly an antismoking policy on both students & teachers and enforce consistently a ban in promoting a healthy school environment(smoke-free schools).

• The KIPS Transactions:PartC
• /
• v.14C no.3 s.113
• /
• pp.239-254
• /
• 2007

Ubiquitous computing supports environment to freely connect to network without restrictions of place and time. This environment enables easy access and sharing of information, but because of easy unauthorized accesses, specified security policy is needed. Especially, ubiquitous sensor network devices use limited power and are small in size, so, many restrictions on policies are bound to happen. This paper proposes double-key based light weight security protocol, independent to specific sensor OS, platform and routing protocol in ubiquitous sensor network. The proposed protocol supports safe symmetric key distribution, and allows security manager to change and manage security levels and keys. This had a strong merit by which small process can make large security measures. In the performance evaluation, the proposed light weight security protocol using double-key in ubiquitous sensor network allows relatively efficient low power security policy. It will be efficient to ubiquitous sensor network, such as smart of ace and smart home.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.23 no.1
• /
• pp.132-140
• /
• 2009

For human exposure assessment of UHF RFID system, electric field distribution of commercial 900[MHz] RFID antenna was measured and analyzed. Also, SAR(Specific Absorption Rate) of RFID antenna was calculated by simulation, and compared with basic restrictions in EMF guidelines. For EMF exposure assessment according to EN and IEC standards, the reader was tested for the normal operation, and electric field from RFID antenna was measured at various distances and angles. For electric field measurement, narrow band isotropic electric field probe was used, and the measurements were made at 0.3, 0.5, 1.0 and 1.5[m] for every 15[$^{\circ}$] angle from the antenna. Also, the rationale for measurement distance in EN and IEC standards is analyzed from the measurement results.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.14 no.11
• /
• pp.2403-2412
• /
• 2010

ENC(Electronic Navigational Chart) is an electronic chart including all kinds of information of nautical chart. Mariners have difficulty reading information because of clutter problem if display scale of ECDIS is lower than compilation scale of ENCs. IRO made SCAMIN improvement model included in S-65 Standard to settle this ENC clutter problem. This SCAMIN model includes both simple restriction that should satisfy some requirement and share geographic information, and hard restriction that should overlap with area object such as depth area, land area, dredge area. It also apply SCAMIN step of sounding value according to importance of safety navigation. In this paper, we analyzed the restrictions for SCAMIN model of S-65 Standard, developed algorithm and application to apply theses restrictions reasonably and mechanically. Also we applied this algorithm and application to Korea ENCs and evaluated the result of performance.

• The KIPS Transactions:PartC
• /
• v.8C no.5
• /
• pp.615-620
• /
• 2001

This paper is a study on the model that measures economic values for the non-market properties of Electronic Commerce(EC). For development of this model, first of all, we reviewed the properties of EC service, and looked around the relation between customer satisfaction and/or payment value and EC properties. In addition, we checked the method to measure economic values of these properties. This measurement method is the contingent valuation method which is a method of measuring the value of the environmental product. We modified it to adapt to the EC. Finally, in this paper, we proposed an economic value model which measures the value of willingness to pay(WTP) to our objectives. However, there could be some restrictions at the time when surveying empirically. Therefore, the succeeding study should be done in order to improve these restrictions some day.

• The KIPS Transactions:PartD
• /
• v.9D no.5
• /
• pp.819-826
• /
• 2002

The mobile vector map services for mobile devices, specially for PDA, are being popularized with the advent of KVM (Kilobytes Virtual Machine). However, the services for cellular phone have some problems for implementation, which are the restrictions of bandwidth, resource of the phone, etc. Thus, these restrictions force to develop new map database exclusively for cellular phone services. But, this approach needs high costs and could not support multi user view for a same area. Therefore, we suggest new client/server system for mobile vector map services, using existing general map database, and design and implement the system. The suggested system, which has minimized functions at client and processes map simplification works at sever, makes it possible to serve mobile vector map without developing new map database only for cellular phone.

• IE interfaces
• /
• v.25 no.3
• /
• pp.347-356
• /
• 2012

The acquisition cost of defense weapon system has been continuously increasing because of art-of-technology of it. This phenomenon requires efficiency and transparency in the weapon system acquisition process through cost estimation. Therefore cost estimation is very important to the government acquisition programs to support decisions about funding and to evaluate resource requirement as a key decision point. The Commercial parametric cost estimating models have been using extensively to obtain appropriate cost estimates in early acquisition phase. These models have many restrictions to ensure the cost estimating result in Korean defense environment because they are developed based on foreign R&D data. Also estimation results are different from Korean defense industry accounting system. So, some studies have been tried to develop a CER (Cost Estimation Relationship) based on the Korean historical data. However, there are some restrictions to improve the predictability and ensure the stability of the developed singular CERs which consider the following data characteristics individually. The the abnormal conditions of data that is multicollinearity, outlier and heteroscedasticity under rack of the number of observations. In this paper, a CER's Linear Combining Model is proposed to overcome those limitations which guarantee more accurate estimation (25.42% higher precision) than other singular CERs. At least, this study is meaningful as a first attempt to improve the predictability of CER with insufficient data. The methodology suggested in this study will be useful to develop a complex Korean version cost estimating model development in future.