• KIEAE Journal
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• v.7 no.4
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• pp.147-152
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• 2007

Numerous non-destructive tests(NDT) to assess the safety of real structures have been developed. System identification(SI) techniques using dynamic responses and behaviors of structural systems become an outstanding issue of researchers. However the conventional SI techniques are identified to be non-practical to the complex and tall buildings, due to limitation of the availability of an accurate data that is magnitude or location of external loads. In most SI approaches, the information on input loading and output responses must be known. In many cases, measuring the input information may take most of the resources, and it is very difficult to accurately measure the input information during actual vibrations of practical importance, e.g., earthquakes, winds, micro seismic tremors, and mechanical vibration. However, the desirability and application potential of SI to real structures could be highly improved if an algorithm is available that can estimate structural parameters based on the response data alone without the input information. Thus a technique to estimate structural properties of building without input measurement data and using limited response is essential in structural health monitoring. In this study, shaking table tests on three-story plane frame steel structures were performed. Out-put only model analysis on the measured data was performed, and the dynamic properties were inverse analyzed using least square method in time domain. In results damage detection was performed in each member level, which was performed at story level in conventional SI techniques of frequency domain.

• Journal of Technologic Dentistry
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• v.30 no.1
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• pp.73-82
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• 2008

This study has been analyzed to write an ideal training evaluation table after analyzing validity of content organization and assigning score of evaluating elements of clinical practice of Dept. of dental technology. 220 junior students who are studying dental technology in D university in Daegu were questioned to analyze the relationship of content organization and score of clinical practice evaluation table. The corrected material has been inspected by SAS V8 for Windows. The results are as following. 1. The validity of content organization of clinical practice evaluation table has a result which can be reliable over than 70% but the validity of score shows low reliance. c 2. The validity of content organization of detail elements of clinical practice evaluation shows that overuse of material and attentiveness(3.78) and responsibility (3.60) are high response but in score organization, the validity shows that safety measure(2.36) when controling machines, arrangement(2.98) after use and ability (2.98) of solving problems are very low. 3. In the elements without interpersonal relation, it shows that those are related to each other. its grading is p < 0.01 so it appears to be meaningful. 4. In result of analyzing the effect to 'studying amount' mark in clinical practice evaluation mark, it appears the element of attitude for job to affect it. And in result of analyzing the effect to 'training attitude' mark, it appears the element of 'controling machines' to affect it. For these results, to be a better evaluation tool, it should be modified by continuous research with arranging evaluation elements to be marked differently in between elements.

• Journal of the Korean Electrochemical Society
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• v.15 no.3
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• pp.115-123
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• 2012

As the market of lithium secondary batteries moves from mobile IT devices to large-format electric vehicles or energy storage systems, the strengthened battery specifications such as long-term reliability longer than 10 years, pack-level safety and tough competitive price have been required. Moreover, even though high power properties should also be achieved for hybrid electric vehicles, it is not easy to measure accurate power values at various conditions. Because it is difficult to choose a proper measurement method and its experimental condition is more complex comparing to capacity measurement. In addition, the power values are very sensitive to power duration time, state-of-charge (SOC) of cells, cut-off voltages, and temperatures, whereas capacity values are not. In this paper, we introduce three kinds of power measurement methods, hybrid pulse power characterization (HPPC) suggested by US FreedomCar, so-called J-pulse by Japan electric vehicle association standards (JEVS) and constant power measurement, respectively. Moreover, with pouch-type unit cells for HEV, experimental power data are discussed in order to compare each power measurement.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.6 no.8
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• pp.1251-1258
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• 2002

The weather FAX machine is the one of necessary of safety navigation for ship. which is the machine which make the weather image by the receiving radio signal which is modulated using FSK method and transmitted on air by coast station. after Coast station scan the weather image and broadcast the image with black dot to 1500Hz and white dot to 2300Hz using FSK modulation. This paper implement weather fax machine using only general IBM-PC by software. By using IBM-PC we can make some good functions like print, edit, save etc. The modulated signal from SSB go into RS232C port via photo coupler not to give damage to PC. by using Timer Interrupt and RS232C serial interrupt, we can measure signal frequency and remake weather image. This paper use only IBM-PC with general SSB receiver which is widely spread on the ship. so this is very economic and possible to implement mutifunctions.

• Journal of the Korean Institute of Navigation
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• v.12 no.2
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• pp.43-55
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• 1988

The amount of cargoes and fishery production have increased continuously during the last decade due to the great growth of the Korean economy. These increasements have made our coastal traffic congested, and the future coastal traffic is also expected to increase considerably. The increased traffic can be a cause of large sea pollution as well a s greater sea casualties us as properties and human lives, which could result in a big national loss. In order to prevent the sea casualties and promote the safety of coastal traffic, the Vessel Traffic Management System (VTMS) along the Korean coastal waterway is inevitably introduced. But, the precise evaluation is necessary required prior to the implementation of VTMS because this system necessitates a huge amount of budgets. This paper aims to propose the model of evaluation process, but the evaluation as to the urgency of establishment is not only very complicated and fuzzy but also affected by the subjectivity of human. Therefore, fuzzy integral is adopted as the mathematical model of evaluation in which decision-maker can intervence by making decision considering the calculated membership-function. Four aspects, namely, the frequency of sea-casualities, the traffic volume, the frequency fuzzy day, and the complexity of waterway are selected as the item of evaluation, and the fuzzy measure are applied to the evaluation of 8 candidated regions such as the adjacent area to the port Inchen, Kunsan, Mokpo, Wando, Yosu, Pusan, Pohang, Donghae. As a result of evaluation, the priority as to the candidated regions is obtained, and the following prior execution regions, namely, the adjacent area to the port Pusan, Yosu, Mokpo & Wando are selected by considering the present situation, but, in the long run, the VTMS should be executed in the whole coast of the nation, through the cost-effectiveness analysis.

• Journal of the Korean Geosynthetics Society
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• v.10 no.2
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• pp.21-28
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• 2011

Several theoretical soil nonlinear models to predict damping ratio, which is one of the typical dynamic properties of soils, it is impractical to predict damping ratio. The resonant column and torsional shear test(RC-TS) is used to represent the dynamic behavior of soils from intermediate to medium shear strains. A limitation of RC-TS is measure precise shear strain in large strains and the modified equivalent radius($R_{eq}$) was obtained using both modified hyperbolic model and Ramberg-Osgood model. Bonneville clays were tested using RC-TS test to obtain rotation and torque. The measured rotation and torque were then compared with calculated rotation and torque using curve-fitting method. Then, the nonlinear soil model parameters were obtained and the equivalent radius was calculated using the model parameters.

• Convergence Security Journal
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• v.12 no.6
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• pp.31-37
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• 2012

Today, the core technology of an automobile is becoming to IT-based convergence system technology. To cope with many kinds of situations and provide the convenience for drivers, various IT technologies are being integrated into automobile system. In this paper, we propose an convergence system, which is called Augmented Driving System (ADS), to provide high safety and convenience of drivers based on image information processing. From imaging sensor, the image data is acquisited and processed to give distance from the front car, lane, and traffic sign panel by the proposed methods. Also, a converged interface technology with camera for gesture recognition and microphone for speech recognition is provided. Based on this kind of system technology, car accident will be decreased although drivers could not recognize the dangerous situations, since the system can recognize situation or user context to give attention to the front view. Through the experiments, the proposed methods achieved over 90% of recognition in terms of traffic sign detection, lane detection, and distance measure from the front car.

• Journal of Construction Engineering and Project Management
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• v.2 no.1
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• pp.14-19
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• 2012

Maturity models allow organizations to assess and compare their own practices against best practices or those employed by competitors, with the intention to map out a structured path to improvement. This research explores the aspects of the Maturity Models that are relevant to distinguish them from one to another. The different Project Management maturity models for define maturity differently and measure different things to determine maturity. Because of this, organizations should give careful consideration to select appropriate maturity model. The main reason behind this research lies on the modification to the existing Organizational Project Management Maturity Model (OPM3) by adding four knowledge areas, dedicated to construction industry as best practices. These are Safety, Environment, Financial and Claim Management. This Model contains (Yes/No) questions; all of these questions must be answered before the user reviews the results that describe the overall maturity and areas of strength and weakness of an organization. The research presents the implementation of the proposed Model Construction Enterprises Maturity Model (CEM2). All the components of the developed Model have been implemented in Microsoft Access. CEM2 helps Construction Enterprises to assess their Maturity Level and know Areas of Weaknesses for future improvement. The easy to use Yes/No user interfaces help enterprises' employees to assess the maturity level of their enterprises. The Model maintains users' responses in its database; as such, many employees from different enterprise divisions can be involved during assessment phase in several sessions.

• Journal of the Korean Institute of Gas
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• v.2 no.4
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• pp.34-41
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• 1998

To oxide film, $A1_2O_3,\;Ta_2O_5$ and $ZrO_2$, coated on stainless steel (SUS410, SUS304) and pure Fe using RF magnetron sputtering method, the corrosion resistance on oxide coatings was studied using electrochemical measurement. Also, the adherence between film and substarte was studied. The adherence index ( $\chi$ ) was determined by the measure of micro hardness test. In this paper, we know that oxide film coated on SUS304 have better corrosion resistance than that coated on SUS410. In oxide film, the difference of corrosion resistance due to crystal structure have not been showed. In evaluating defect area rate of ceramic coated materials, CPCD method can be used effectively. In the micro-hardness test, with $1{\mu}m$ thickness film, it has only one the value of $\chi$. Above $2{\mu}m$ thickness film, however, get another value of $\chi$ as the cracks in film. The oxide film adhere well on the mild materials such as pure steel than high intensity materials like stainless.

• Journal of the Ergonomics Society of Korea
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• v.29 no.3
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• pp.311-320
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• 2010

This study aimed to examine the development and characteristics of the workers with upper limb musculoskeletal symptoms and disorders and to analyze the upper limb musculoskeletal symptoms and disorders for its relationship with the individual socio-demographic characteristics. This study investigated the effect on the limitations of physical activities using standardized surveillance tool and clinical diagnosis. Musculoskeletal symptoms and the limitations of physical activities were examined. The clinical diagnosis of musculoskeletal disorders were carried out by physical examination, radiological examination and electromyography-electroneuronography for 22 workers in kitchen hood assembly process and 50 workers in toggle process of leather product manufacturing. The proportion of workers with musculoskeletal disorders was higher and the DASH score was also statistically higher in female and aged workers with longer working hours, longer household working hours, less leisure/hobby activity and higher physical load. Physical activities component score increased in the following order: workers in normal health, workers with musculoskeletal symptoms, and workers with musculoskeletal disorders as clinically diagnosed. Score for each DASH component increased in the following order: sports/performing arts ability, social activities, specific physical functional activities, work or other regular daily activities, work ability, psychological activities, insomnia and upper limb symptoms. The overall and each component DASH scores were higher in workers with symptoms of status praesens and of more severity, and receiving medical intervention. Musculoskeletal symptoms and disorders are associated with individual socio-demographic characteristics, and DASH score for physical activities of upper limb was higher in workers with musculoskeletal disorders. Musculoskeletal symptoms and disorders have a remarkable epidemiological significance for physical activities, social activities, work or other regular daily activities, upper limb symptoms and insomnia, where work ability, sports/performing arts ability and preventive measure is needed.