• Journal of Power System Engineering
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• v.18 no.4
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• pp.104-111
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• 2014

In this study, EH36 is thick steel plate, which welded by auto $CO_2$ gas welding machine, has been applied on offshore filed. The specimen was examined by indentation tester and it was measured for fracture toughness at $18^{\circ}C$, $0^{\circ}C$, $-20^{\circ}C$ and $-45^{\circ}C$ by low temperature chamber, respectively. The absorbed energy was got on same temperature by Charpy impact tester. The weld surface was observed for watch of changed crystalline structure by optical microscope, and fracture surface of impact test specimen were observed by scanning electron microscope(SEM).

• Computers and Concrete
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• v.20 no.6
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• pp.711-718
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• 2017

Nanotechnology is a new filed in concrete structures which can improve the mechanical properties of them in confronting to impact and blast. However, in this paper, a mathematical model is introduced for the concrete models subjected to impact load for wave propagation analysis. The structure is simulated by the sinusoidal shear deformation theory (SSDT) and the governing equations of the concrete model are derived by energy method and Hamilton's principle. The silicon dioxide ($SiO_2$) nanoparticles are used as reinforcement for the concrete model where the characteristics of the equivalent composite are determined using Mori-Tanaka approach. An exact solution is applied for obtaining the maximum velocity of the model. In order to validate the theoretical results, three square models with different impact point and Geophone situations are tested experimentally. The effect of different parameters such as $SiO_2$ nanoparticles volume percent, situation of the impact, length, width and thickness of the model as well as velocity, diameter and height of impactor are shown on the maximum velocity of the model. Results indicate that the theoretical and experimental dates are in a close agreement with each other. In addition, using from $SiO_2$ nanoparticles leads to increase in the stiffness and consequently maximum velocity of the model.

• Progress in Superconductivity and Cryogenics
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• v.9 no.3
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• pp.13-15
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• 2007

We employed home-made position marking module in the scanning Hall probe system. The module is composed of two coils of which gap, a, between wires in a coil is $500{\mu}m$. We appiled 10-35mA of current with 15Hz in the coils and recorded ac corresponding magnetic field signal with respect to measuring time while we measured DC field profiles produced due to superconducting film in a perpendicular magnetic field. We calibrate the position, x, of coils using the measuring time and location of the coils in the holder. The error range was about ${\pm}0.1mm$. We test the module as we applied current of 100A and filed of 1kG in the superconducting tape. It was confirmed that there was no interference between superconducting tape and marking coils.

• International conference on construction engineering and project management
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• 2020.12a
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• pp.443-452
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• 2020

Worker's awkward postures and unreasonable physical load can be corrected by monitoring construction activities, thereby increasing the safety and productivity of construction workers and projects. However, manual identification is time-consuming and contains high human variance. In this regard, an automated activity recognition system based on inertial measurement unit can help in rapidly and precisely collecting motion data. With the acceleration data, the machine learning algorithm will be used to train classifiers for automatically categorizing activities. However, input acceleration data are extracted either from designed experiments or simple construction work in previous studies. Thus, collected data series are discontinuous and activity categories are insufficient for real construction circumstances. This study aims to collect acceleration data during long-term continuous work in a construction project and validate the feasibility of activity recognition algorithm with the continuous motion data. The data collection covers two different workers performing formwork at the same site. An accelerator, as well as portable camera, is attached to the worker during the entire working session for simultaneously recording motion data and working activity. The supervised machine learning-based models are trained to classify activity in hierarchical levels, which reaches a 96.9% testing accuracy of recognizing rest and work and 85.6% testing accuracy of identifying stationary, traveling, and rebar installation actions.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.11 no.5
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• pp.7-14
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• 2012

We frequently confront with cars interfering into our lane on the ramp. We suffered from serious traffic congestion due to the interfering cars. But the police enforcement has not done actively because it's hard to enforce. In this study, we have evaluated the systems to enforce cutting-in cars through the field test. Generally, the image processing method depends on the weather. To overcome this limitation we proposed a new algorithm combined with section detection method. In the filed test we concluded the results as follows. Whereas the violation detection rate of the general image processing was 58.2%, a new algorithm proposed by this study was 74.5%. And, an error rate enforcing vehicles that do not violate was 0.0%. Also, we can use the existing facilities, such as street light because of compact and lightweight systems which are integrated camera with controller. Therefore, we concluded that it is possible to enforce the interfering Cars using vehicle enforcement systems.

• The Journal of the Korea Contents Association
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• v.15 no.7
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• pp.170-180
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• 2015

With progress in emerging new media technology and associated device, there is growing interest in a new type of contents in the filed of children education. In this research, we developed a edutainment content for enhancing sociability and visual perception of children exploiting kinect. Recreating what is visually perceived with physical movement is adopted to develop visual perception. It is also designed such that one's sociability can be enhanced through experiencing natural physical contact and collaboration while interacting with the developed content. The prototype of the content was created through development of character to boost interest, a short animation for storytelling, and interactive programming. In the second pilot test which was done with the content improved through the first pilot test, it was observed that children easily played with it and actively participated in experiencing it. From this observation, it is expected that the developed content may work as a promising edutainment content which fosters children to enhance visual perception and sociability through natural interaction.

• Korean Journal of Human Ecology
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• v.5 no.1
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• pp.43-53
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• 1996

The purpose of this study was to investigate the actual condition of fashion sales related persons and analyze their different role recognition in women's Ready-To-Wear shops. A questionnaire was administered to 378 fashion sales related persons in department stores and individual shops. Data were analyzed by using crosstabs, $X^2$, t-test, Scheffe's test and ANOVA by using of SPSS PC program. The results of this study were as follows: 1. In the role of fashion salespersons, managers participated highly in the merchandise buying plan, actual merchandise buying and advertisement, and shopmasters participated in the management of salespersons and keeping good relation with customers and display. 2. There was significant difference according to the existence of shopmasters in sales promotion. Shops with shopmasters had regular sales and filed up customer cards. 3. Shopmasters and salespersons attached importance to fashion information, market information, sales result information, and managers attached importance to customer information, enterprise environment information in utilizing of informations. Managers considered customer survey very important but shopmasters and salespersons did not. Shopmasters, managers, and salespersons all attached importance to customers' preference survey as customers' information source. 4. There were significant differences in lifestyle survey, buying method survey, preference survey, street fashion survey, brand identity survey and advertizement effect survey of customers by the different roles of fashion salespersons. 5. There were significant differences in the degree of merchandise knowledge, service and after service in sales service recognition by the different roles of fashion salespersons.

• Journal of the Korean Geotechnical Society
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• v.19 no.5
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• pp.233-241
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• 2003

Geotextile tube is hydraulically filled with dredged materials and has been applied to coastal protection and scour protection, dewatering method of slurry, and isolation of contaminated material. Recently, geotextile tube technology is no longer alternative construction technique but suitable desired solution. In this paper, the numerical analysis was performed to investigate the behavior of geotextile tube with various properties of geotextile sheet and hydraulic pumping conditions. Numerical analysis was executed to compare with the results from the large-scale field model tests, and also with those of plane strain analysis and 3-D FEM analysis. A geotextile tube was modeled using the commercial finite element analysis program ABAQUS and the one-quarter of tube was modeled. Behavior of geotextile tube during the hydraulic pumping procedure was analyzed by comparing the large-scale field model test and numerical analysis. The shape variation and maximum tube height between the numerical analysis results and large-scale filed test results are turned out to be in a good agreement.

• Journal of Families and Better Life
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• v.8 no.2
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• pp.31-47
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• 1990

The purpose of this paper is to investigate the relationship between the married people's conflict level and coping behavior, and find out how independent variables(male or female, age, level of education, family income, religion, types of marriage, types of family) have an effect on two dependent variables. The research problems as follows: 1) How independent variables influence on the level of conflict. 2) How independent variables influence on the coping behavior 3) How related the level of conflict and th coping behavior. Two instruments wee administrated to 302 married man and woman in Seoul, in June, 1990 The first instrument, 25 items questionnaire, made by investigator, was developed based upon Lee Sun and Moon Sung Sun. The second instrument, 20 item questionnaire, based upon filed , and modified to be appropriate to Korean Culture, Data was analyzed by frequency, percentage, mean, t-test, F-test and pearson r. The results are summarized as follows; 1) Most husbands and wives how the middle level of conflict 2) Among independent variables, male or female(p<.05), level of education (p<.05), types of family (p<.05), were variables to have influence on the level of conflict. 3) Husbands and wives's coping behavior are relatively middle level. 4) Among independent variables, types of marriage(p<.05) was variable to have influence on the coping behavior. 5) There were very low positive correlation (r=.15, p<.01) between the level of conflict and the negative coping behavior, and very low negative correlation(r=-.21, p<.001) between the level of conflict and the positive coping behavior. Form this results, more objective methods and research are needed to develop the style of conflict and the coping behavior.

• Journal of the Korea Convergence Society
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• v.11 no.1
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• pp.25-31
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• 2020

In this study, a real time image integrating system which can reconstruct two images from a surface camera and an under water camera into one new image was developed to support Korea artistic swimming team. The developed system consists of four USB cameras (two USB 2.0 and two USB 3.0) sealed in water proof case and one note book computer, and a LabVIEW based real time image merging program was developed. During field test, problem in cooperative motion of acrobatic formation was found, and it was proved that correction of motion to improve skill of the player could be possible in real time with aid of the developed system. After the filed test, the developed system has been being used to support Korea artistic swimming team.