• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2008.11a
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• pp.753-757
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• 2008

The objects of this study are to increase the efficiency and competitiveness for construction management and field supervision by using IT technology which is a trend of construction industry thesedays. Using RFID technology can play an important role to achieve the goal, but it is necessary to research a standard of using frequency, specific, protocol, package method and reading method because it is hard to apply RFID to physical, chemical, environmental specifics. In this study as a part of planning research to standardize, a limitation item Is conducted with RFID tag attached building materials, and RFID Tag goods which solve the restriction are produced to conduct a field application test. From the result, available reading distance is different according to physical and environmental specifics. Furthermore because the different application method and attaching method make a various management efficiency, the current management of construction materials is analyzed and applied to a construction field to provide to various limitation items and recovery plan.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.33 no.9
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• pp.709-717
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• 2009

Heat transfer rate is a very important factor for the performance of a steam reformer because a steam reforming reaction is an endothermic reaction. Coaxial cylindrical reactor is the reactor design which can improve the heat transfer rate. Temperature, fuel conversion and heat flux in the coaxial cylindrical steam reformer are studied in this paper using numerical method under various operating conditions. Langmuir-Hinshelwood model and pseudo-homogeneous model are incorporated for the catalytic surface reaction. Dominant chemical reactions are assumed as a Steam Reforming (SR) reaction, a Water-Gas Shift (WGS) reaction, and a Direct Steam Reforming (DSR) reaction. Although coaxial cylindrical steam reformer uses 33% less amount of catalyst than cylindrical steam reformer, its fuel conversion is increased 10 % more and its temperature is also high as about 30 degree. There is no heat transfer limitation near the inlet area at coaxial-type reactor. However, pressure drop of the coaxial cylindrical reactor is 10 times higher than that of cylindrical reactor. Operating parameters of coaxial cylindrical steam reformer are the wall temperature, the inlet temperature, and the Gas Hourly Space Velocity (GHSV). When the wall temperature is high, the temperature and the fuel conversion are increased due to the high heat transfer rate. The fuel conversion rate is increased with the high inlet temperature. However, temperature drop clearly occurs near the inlet area since an endothermic reaction is active due to the high inlet temperature. When GHSV is increased, the fuel conversion is decreased because of the heat transfer limitation and short residence time.

• Journal of Korea Society of Digital Industry and Information Management
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• v.11 no.3
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• pp.11-19
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• 2015

Due to recent development in mobile devices, the mobile device utilization and many related applications have been increasing. Most of initial applications on mobile devices just showed simple information, but now they processes huge data. However, smart devices have certain limitations in processing massive data. Especially, if the size of data increases, the speed of data processing adversely decreases, so the performance of programs also decreases. If hardware specification of the mobile devices is not enough to handle it, response time will be drastically delayed. To overcome these drawbacks, most of application running on mobile devices communicate with their servers to manage data. XML is a proper language for data communication to send and receive data between servers and mobile devices, because it defines rules of document's format and it is a textual data format and small-sized language. However, mobile devices have limitation such as memory, CPU and wireless network to process huge data and XML also takes a lot of time to communicate with servers and devices and handle data, so it could be overhead in service time. Binary XML is an alternative of performance improvement in data processing, which has XML's benefits and minimizes the XML size by binary coding. However, most of binaryXML which are used on applications don't fit on mobile applications. In this paper, we surveyed many kinds of binaryXML, compared merits and demerits to find a binaryXML for mobile applications. We propose how to use binary XML and implemented an electronic attendance system using binary XML to overcome the limitation of XML and to reduce the load of data communications between servers and devices.

• Journal of Educational Research in Mathematics
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• v.26 no.4
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• pp.755-768
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• 2016

According to TIMSS, secondary math teachers in Korea has lower confidence compare to other countries, despite the fact that teachers' confidence of teaching is an important variable. This not only influences the student's improvement but, also the quality improvement of teachers' career. Therefore, this study explores the effect of secondary math teachers' confidence according to the context variables such as teaching years, teaching preparation, collaboration with other teachers, and teaching limitation. Additionally, these context variables' $R^2$ toward the change of teaching confidence is also included. Results indicate that teaching preparation, collaboration with other teachers, and teaching limitation contribute in the confidence of teaching. $R^2$ of the change of teaching confidence shows large contribution to teaching preparation which does not accomplish with other variables.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.19 no.3
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• pp.253-261
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• 2001

Nowadays, various water quality prediction models have been studied, then these models can support the method which evaluate the effect of various alternative water quality management by simulation without experimentation. But, It is necessary to create complex input data file for applying these water quality model and even though the appropriate result is extracted, it is impossible to use as decision making data effectively because of the limitation of expression of model itself. As this study is about the stream water quality modeling, for overcoming the model's above limitation, by developing an interface which can calculate the pollutant load of watershed, I could create a input data file and visualize the simulation result so that I was going to integrate water quality model and GSIS using Flexible coupling applied to GSIS in the pre-process and post-process on model. The QUAL2E model, used in this study, is verified by stream water quality model in previous various results of study and has many examples through previous study, because that is appropriate to water quality model, especially in Korea, and comparatively accurate and their usage is quite simple.

• Journal of the Korean Society for Nondestructive Testing
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• v.32 no.2
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• pp.185-191
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• 2012

Typically, a wedge is involved to generate effectively high inspection angle in pipe weld inspection using phased array ultrasonic technique. But the usage of this wedge for weld or access limited area can cause coverage limitation for the examination volume because of the wedge front length. Therefore, the shear wave phased array probe which can generate high inspection angle without wedge is essentially necessary. In this paper, the shear wave phased array ultrasonic probe which can generate high inspection angle designed by modeling and manufactured from the modelling result. And this shear wave probe tested whether it can detect and sizing for EDM test block that contains various depth. As results, the experimental results show that the designed shear wave phased array probe can detect and size with reliable accuracy. Therefore if this phased array probe apply in field inspection, it is expected that it show more reliable inspection result for plant structure having access limitation.

• Journal of Korean Society of Water and Wastewater
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• v.29 no.4
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• pp.493-502
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• 2015

In accordance with the Watershed Sewer System Maintenance Plan enforced on February 2, 2013, the different compliance concentration of effluent limit be applied to effluent discharged from public sewage treatment works(PSTWs) in each watershed on the basis of water quality thereof. With the introduction of watershed sewer system, it is necessary to set the compliance concentration of effluent limit for PSTWs situated in the watershed, by region and PSTW size, to achieve water quality criteria for regional watersheds or target water quality under TMDL program. Watershed Environmental Agencies establish the Watershed Sewer System Maintenance Plan and set the compliance concentrations of effluent limit for PSTWs under the plan. The agencies plan to apply tougher effluent BOD concentration limits in Class I to IV areas. Effluent BOD concentration limits will be toughened from 5~10 mg/L to 3 mg/L in class II~III areas, from 10mg/L to 5mg/L in class IV areas. Uniform application of effluent BOD concentration limits to PSTWs in the watershed sewer system need to be complemented considering type of sewage treatment technology employed and watershed characteristics. Therefore, this study presents method to determine the compliance concentration of effluent limit from PSTWs in the watershed.

• CRM연구
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• v.1 no.1
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• pp.49-69
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• 2006

Previous studies, Technology Acceptance Model (TAM) and Post Acceptance Model (PAM) have a little limitation in time series analysis. To solve this limitation, we used system dynamics as research methodology and designed simulation model based on TAM and PAM. Moreover, we designed new simulation model which can analyize time series data in customers' demand change from initial acceptance to post acceptance. This study targeted domestic mobile phone market. The simulation results showed that diffusion graph was similar to real data. That means we validated our simulation model. Since the simulation model offers the graph of customer's demand change by time, so it can be useful as a leaning tool. Therefore, we think this study helps IT companies use the model for forecasting of market demand.

• Journal of Korea Multimedia Society
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• v.14 no.2
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• pp.228-237
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• 2011

The risk of leakage or theft of critical data which is stored in database is increasing in accordance with evolution of information security paradigm. At the same time, needs for database security have been on the rapid increase due to endless leakage of massive personal information. The existing technology for prevention of internal information leakage possesses the technical limitation to achieve security goal completely, because the passive control method including a certain security policy, which allows the only authorized person to access to DBMS, may have a limitation. Hence in this study, we propose Query Signature System which signatures the queries accessing to the critical information by interrupting and passing them. Furthermore this system can apply a constant security policy to organization and protect database system aggressively by restricting critical query of database.

• The Journal of Korean Physical Therapy
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• v.17 no.1
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• pp.43-68
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• 2005

The purpose of this study was to report the physical status of adult with cerebral palsy who live in local community areas including Seoul, Busan, Daegu in Republic of Korea at 2004. 202-individuals with cerebral palsy(140 male, 62 female; mean age 31.9 years; range 19 to 64 years) were surveyed. Measures included a 29-item self-reported health status measure focusing on musculoskeletal status and functional performances. Adult cerebral palsy required continuous management for musculoskeletal and ambulatory function through therapeutic approach. This survey is restricted to population who had cared in welfare center for cerebral palsy in local community, so it needs to investigate home-residual adults with cerebral palsy and the population in rural community. The results were as follows: 1. Participants reported that they had a limitation of a daily of life activity due to musculoskeletal pain($43\%$), there was significant differences between a limitation of a daily of life activity and the decreased ambulatory function(p<.05). 2. Thirty six point six percentile of participants had the decreased ADL function, it was significant related with the impaired body location(p<.05) 3. Thirty nine point one percentile of participants who can independently gait had the decreased ambulatory function, it was significant differences with the usage of ambulatory assistive devices(p<.05). 4. There was significant differences ambulatory function both the body region with impairment and a grade of disability(p<.05). 5. Sixteen point three percentile of participants could not ambulate any more, there was significant differences between a age and a point of time for non-ambulation(p<.05). 6. There was significant differences between ambulatory function and physical activity(p<.05).