• Transactions of the Korean Society of Mechanical Engineers A
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• v.34 no.10
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• pp.1351-1357
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• 2010

Water monitoring equipments using daphnia can be used to monitor the pollution levels of a country's main rivers. Such equipments should be capable of providing a prompt warning about increase in the contamination levels, which is evaluated on the basis of impulse number or toxicity index. As unmanned remote control equipments, they must provide reliable pollution monitoring results for each season and for the annual physical changes in each river. Two different equipments based on the impulse number and toxicity index showed different results for the operating rates and for the number of emergency checks required even though both were operated at the same conditions. The results are affected by many parameters such as the presence of any air bubbles and the microscopic pressure. The purpose of this study is to develop a method that can reduce the effect of bubbles or microscopic pressure on the monitoring data. We expect to achieve reliable monitoring data for water pollutants irrespective of the location of the equipment setup.

• Journal of the Korean Society of Safety
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• v.32 no.4
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• pp.59-65
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• 2017

This study examined the stakeholder cognition of the safety certification marking system by surveying manufacturers, lessors, and users. In addition, among various issues about safety certification marking systems, the improvement of safety certification marking contents was suggested in order to guarantee quality of temporary equipments. The results by statistical method show that it is necessary to increase of users' understanding about the safety certification marking system. In addition, the quality management system of temporary equipments should be introduced to control the actual condition that temporary equipments of various product companies are mixed in a site during removal and reuse processes. For detailed marking contents, it is recommended that a certification mark, an identification number, and the production year should be displayed and the manufacturer name could be selectively presented. Detail informations such as a safety certification number, a product company, a model type or name, a specification, a weight, a product number, and the location of a certification mark should be identified by the identification number.

• Smart Structures and Systems
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• v.15 no.4
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• pp.1121-1137
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• 2015

This study presents probabilistic-based damage identification technique for highlighting damage in metallic structures. This technique utilizes distributed piezoelectric transducers to generate and monitor the ultrasonic Lamb wave with narrowband frequency. Diagnostic signals were used to define the scatter signals of different paths. The energy of scatter signals till different times were calculated by taking root mean square of the scatter signals. For each pair of parallel paths an error function based on the energy of scatter signals is introduced. The resultant error function then is used to estimate the probability of the presence of damage in the monitoring area. The presented method with an autofocusing feature is applied to aluminum plates for method verification. The results identified using both simulation and experimental Lamb wave signals at different central frequencies agreed well with the actual situations, demonstrating the potential of the presented algorithm for identification of damage in metallic structures. An obvious merit of the presented technique is that in addition to damages located inside the region between transducers; those who are outside this region can also be monitored without any interpretation of signals. This novelty qualifies this method for online structural health monitoring.

• Journal of Korea Technology Innovation Society
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• v.20 no.1
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• pp.205-238
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• 2017

Display industry in Korea has been rapidly developing over 20 years, now taking the top-class leading position in the world. Nevertheless, many previous studies have mainly focused on major panel set makers. To overcome the drawbacks, this study focuses on supplier companies in the upstream of display industry such as materials, components, and equipments sectors. The research method used in this study is an industry value chain perspective combined with architectural innovation approach. Display panel is produced through fabrication process and modular process, each having a different characteristics of process architecture. This research figured out that there are quite a different development characteristics between materials and components suppliers and equipment suppliers. The number and revenue of materials and components suppliers were quite larger than equipments suppliers. However, the former has been growing mainly in the field of modular process, having a very weak position in the field of fabrication process. On the contrary, equipments suppliers have been showing a continuously growing pattern in the field of fabrication process. The R&D expenditures between these two kinds of suppliers showed a similar pattern. The fabrication process of display panel production is characterized as a highly integral architecture characteristics, so as to be a strong barriers to local suppliers, resulting less development of materials and components suppliers in Korea.

• Journal of Korea Multimedia Society
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• v.15 no.3
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• pp.299-311
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• 2012

Recently, H.264 SE(scalable extension) has become a standard of next generation multimedia service which is one source, multi-user service in the telecommunication environment of different kinds of networks and terminal equipments. But existing DRM schemes for multimedia service are not fit for H.264 SE system. Because the amount of transmitted multimedia data is changed considering network environment and terminal equipments' performance by the system, but in the existing DRM schemes, the amount of handled multimedia data are not variable according to network environment and terminal equipments' performance. In this paper, an information security scheme combined video watermarking and encryption is presented for H.264 SE. Amount of watermarks and embedding positions are calculated by the frame number of enhancement layers which are created according to the state of networks and terminal equipments. In order to minimize delayed time by video watermarking and encryption, the video data are watermarked and encrypted in the H.264 SE compression process. In the experimental results, we confirmed that proposed scheme is robust against video compression, general signal processing and geometric processing.

• The Journal of the Korea institute of electronic communication sciences
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• v.5 no.6
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• pp.625-630
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• 2010

With regard to the examples of establishing various sorts of information security, it can be seen that there are gradual, developmental procedures including Firewall and VPN (Virtual Private Network), IDS (Intrusion Detection System), or ESM(Enterprise Security Management). Each of the security solutions and equipments analyzes both defense and attack for information security with the criteria of classifying the problems of security policies by TCP/IP layers or resulted from attack patterns, attack types, or invasion through specialized security technology. The direction of this study is to examine latency time vulnerable to invasion which occurs when L2-stratum or lower grade equipments or policies are applied to the existing network through TCP/IP layer's L3-stratum or higher grade security policies or equipments and analyze security holes which may generate due to the IP preoccupation in the process of establishing policies to limit particular IP area regarding the policies for security equipments to figure out technological problems lying in it.

• Journal of Korean Elementary Science Education
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• v.23 no.4
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• pp.305-317
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• 2004

The learning materials in elementary school science textbooks should include all kinds of materials being used by both teachers and students in the science teaching. The major purpose of this research is to analysis textbooks and teacher's guidebooks prepared for the science teaching of 3-6 grade students. To clarify this research, we listed whole of the learning materials of science teaching for each grade and counted numbers being used for whole of the lessons of science. And according to the characteristics and the methods of its preparation of materials, the types of learning materials can be divided into 10 categories such as teaching equipments for science, test materials, consumables, audio-visual aids, teaching equipments in general, collecting' recycling materials, field studies' collected data, breeding' cultivation materials, manufacture materials, and etc. At the result of this research, the 7th national science curriculum needs total 844 items of learning materials for science education. They could be separated into ten types of categories such as 159 items of teaching equipments for science, 65 items of test materials, 116 items of consumables, 198 items of audio-visual aids, 64 items teaching equipments in general, 31 items of collecting' recycling materials, 38 items of field studies (collecting) materials, 17 items of breeding-cultivation materials, 58 items of manufacturing materials, 105 items of other materials. And we found out that there were 332 items of materials for the 3rd grade, 303 items for the 4th grade, 324 items for the 5th grade, and 254 items for the 6th grade. The result of this research could be useful for classroom activities for science teaching.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.6
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• pp.1398-1404
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• 1999

The purpose of this study was to investigate the sanitary management procedures of foodservice in elementary schools in Pusan area. The questionnaire which were administered to 189 dietitians was used in this study as a survey method. The results were as follows. Mean total length of employment for dietitians at school foodservice was 3.7 year. The mean serving scale was 1,052 meals. Meals were served at classroom 63.5%, lunchroom 23.8%, and classroom＋lunchroom 12.7% of the schools. The mean time span required of meal delivery was 31.5min at the classroom serving place. Regarding total mean score of sanitary management procedures, time temperature was 3.48/5.00, personal sanitation 4.20/5.00, equipments and facilities sanitation 3.92/5.00. The mean score of the pre preparation was 3.91/5.00 for time temperature management procedure, those of food purchasing and receiving, food storage, food production, meal. assembly.trasnportation service, and hot.cold holding were 3.83/5.00, 3.82/5.00, 3.71/5.00, 3.25/5.00, 2.30/5.00 respectively. The higher age group(31

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2011.05a
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• pp.351-354
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• 2011

Home network system makes it available for controlling inside home and for controlling from outside as well with personal computer, cellular phone or smart phone, by connecting diverse information equipments within home such as lighting, gas, and heating equipments with network Integrated server and wall-pad, which form home network system, have demerits as saying of being high-priced and of needing to implement network infrastructure. Also, there is also risk, which is unavailable for controlling equipments inside home, or can cause malfunction of equipments given the occurrence of a problem about integrated server This study suggested the intelligent home network system, which uses smart phone of supplementing these merits of home network system. It substituted high-specification input & output equipment in the currently and widely supplied smart phone for display and touch screen, which are user interface part of the existing wall-pad, and suggest the common home network system by concentrating management and control function of home network on smart phone.

• Journal of Navigation and Port Research
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• v.38 no.2
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• pp.163-170
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• 2014

Domestic offshore business is oriented toward building drill-ships, FPSOs(Floating Production Storage and Off loading). But the equipments needed for offshore platforms are not so developed in Korea because the equipments can not be verified in Korean territory where the offshore platforms are not stationed. This study aims at finding some methods on entering into OSI for the maintenance and disassembly of fixed offshore platforms. Slack model is adopted to find out how slack assets could play a role in penetrating foreign markets. Firstly, entry into the South East Asian market is recommended. Secondly, forming a consortium is suggested by which taking part in offshore market can be easier. Finally, strategic plans for obtaining the technology for ship building equipments are needed as well as government support.