• Journal of the Korea Concrete Institute
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• v.26 no.2
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• pp.219-227
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• 2014

The purpose of this study is to investigate water purification properties of porous concrete by using effective microorganisms through the long-term continuous flow test. To solve the problems such as desorption of conventional microorganisms, in this study, tertiary treatment of the effective microorganisms identified by 16S rDNA sequence analysis was adopted per each step in the manufacturing process of porous concrete. And concentration for optimum continuous flow test and operation conditions through basic experiments according to retention time were investigated. Based on the experimental results, the porous concrete applying effective microorganisms showed no toxicity on the biological water quality and exhibited excellent removal efficiency than normal porous concrete. Therefore, contaminated water quality would be improved by treatment performance investigation of contaminants through long-term continuous flow test. If problems are complemented during the experiment process, it is expected to be able to reduce the non-point pollution sources flowing into river.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2008.11a
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• pp.587-590
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• 2008

Typically, General contractor in the construction industry can not plan their own of the amount of orders received, and because of the size of wide fluctuations in the amount of annual orders received for equipment or personnel to full-time employment has limits. Therefore, with a vertical division of labor between specialist trades which distributed the risk and the intention to improve the efficiency of production will be. For this reason, the production structure of the general subcontracting relationships are formed. In this way, Depending on the structure of production outsourced management of the project is the impact on the successful completion. Nevertheless, most construction companies do not achieve effective an organized cooperation until now. This study is to understand the actual conditions an organized cooperation between general contractor and specialist trades, and is look at ways to improve with find the complement. This paper is a preliminary study of the leading research based on the present condition of the cooperating companies considered to be the cause. A result of Analysis, the actual conditions in cooperation of the construction industry is staying in an external form of organizational cooperation And were not effective utilization of the organization for the cooperation a production. Specialist trades have had to register as partners for the amount of orders received, the level of practical cooperation was almost no activity to improve a production. in each step an organized cooperation in the construction industry, to improve productivity construction and to create of economic value for the cooperation of production is required.

• Journal of the Korean Society for Nondestructive Testing
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• v.20 no.4
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• pp.276-284
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• 2000

The acoustic emission (AE) behavior of reinforced concrete beams tested under flexural loading was investigated to characterize and identify the source of damage. This research was aimed at identifying the characteristic AE response associated with micro-crack development, localized crack propagation, corrosion, and debonding of the reinforcing steel. Concrete beams were prepared to isolate the damage mechanisms by using plain, notched-plain, reinforced, and corroded-reinforced specimens. The beams were tested using four-point cyclic step-loading. The AE response was analyzed to obtain key parameters such as the time history of AE events, the total number and rate of AE events, and the characteristic features of the waveform. Initial analysis of the AE signal has shown that a clear difference in the AE response is observed depending on the source of the damage. The Felicity ratio exhibited a correlation with the overall damage level, while the number of AE events during unloading can be an effective criterion to estimate the level of corrosion distress in reinforced concrete structures. Consequently, AE measurement characterization appears to provide a promising approach for estimating the level of deterioration in reinforced concrete structure.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2007.11a
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• pp.939-942
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• 2007

Vacuum cleaner is a close life product that can remove various dusts from our surroundings. However well vacuum cleaner clean our environments, many people are looking away from it, due to its loud noise. Its noise causes a big trouble in the usual life, for example, catch calls, TV watching and discussing etc. To reduce these inconveniences, noise reduction methods and systematic design of low noise vacuum cleaner are studied in this paper. At first, sound quality investigation is performed to get the noise level and quality that make people TV watching and catch calls available. Based on the European and domestic customer SQ survey result, sound power, peak noise level and target sound spectrum guideline are studied and introduced. As a second, precise product sound spectrums are designed into each part based on the sound quality result. Fan-motor, brush, mainbody, cyclone spectrums are decided to get the final target sound based on the contribution level. Fan-motor is the major noise source of vacuum cleaner. Specially, its peak sound, RPM peak and BPF Peak, cause the people nervous. To reduce these peak sounds, high rotating impeller and diffuser are focused due to its interaction. A lot of experimental and numerical tests, operation points are investigated and optimization of flow path area between diffusers is performed. As a bagless device, cyclones are one of the major noise sources of vacuum cleaner. To reduce its noise, previous research is used and adopted well. Brush is the most difficult part to reduce noise. Its noise sources are all comes from aero-acoustic phenomena. Numerical analysis helps the understanding of flow structure and pattern, and a lot of experimental test are performed to reduce the noise. Gaps between the carpet and brush are optimized and flow paths are re-designed to lower the noise. Reduction is performed with keeping the cleaning efficiency and handling power together and much reduction of noise is acquired. With all above parts, main-body design is studied. To do a systematic design, configuration design developments technique is introduced from airplane design and evolved with each component design. As a first configuration, fan-motor installation position is investigated and 10 configuration ideas are developed and tested. As a second step, reduced size and compressed configuration candidates are tested and evaluated by a lot of major factor. Noise, power, mass production availability, size, flow path are evaluated together. If noise reduction configuration results in other performance degrade, the noise reduction configuration is ineffective. As a third configuration, cyclones are introduced and the size is reduced one more time and fourth, fifth, sixth, seventh configuration are evolved with size and design image with noise and other performance indexes. Finally we can get a overall much noise level reduction configuration. All above investigations are adopted into vacuum cleaner design and final customer satisfaction tests in Europe are performed. 1st grade sound quality and lowest noise level of bagless vacuum cleaner are achieved.

• Journal of the Korean Society of School Health
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• v.21 no.2
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• pp.119-134
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• 2008

Purpose: The purpose of this study is to understand a variety of intervention studies to prevent smoking by adolescents in U.S. and find out implications for Korea. Methods: This study reviewed articles found in the internet and analysed the data of US DHHS and CDC. Results: The School Health Policies and Programs Study (SHPPS) is a national survey periodically conducted to assess school health policies and programs of U.S. The main components of SHPPS are health education and physical education, health services, mental health and social services, school policies, and school environments. The CDC guidelines for school health programs to prevent tobacco use and addiction are composed of policy, instruction, curriculum, training, family involvement, tobacco-use cessation efforts, and evaluation. School-based interventions to prevent smoking can be classified into the categories of information-giving curricula, social competence curricula, social influence approaches, combined methods draw on social competence and social influence approaches and multi-modal programmes and Youth Empowerment study. The key programs for adolescent smoking prevention are ALERT Project, HSPP, TNT Project, MPP, NC YES. Conclusions: As smoking is often the first step of unhealthy behaviour such as alcohol drinking, illegal drugs, and violence, smoking prevention programmes for adolescents in U.S. have been comprehensive school-based health programs. In smoking prevention programs for adolescents, CDC plays a critical role by supporting survey, research, policy, and funds. The effectiveness of the programs was high when it was based on school and involved parents, community, and mass media. As the effect of each programme is not expected to last for a long time, consistent repetition of these interventions is essential. Current smoking prevention programs for adolescents are exploring the empowerment approach focused on the active involvement of participants rather than traditional approaches using order and discipline.

• Journal of Korean Society on Water Environment
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• v.26 no.5
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• pp.841-849
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• 2010

Soil erosion is an natural phenomenon. However accelerated soil erosion has caused many environmental problems. To reduce soil loss from a watershed, many management practices have been proposed worldwide. To develop proper and efficient soil erosion best management practices, soil erosion rates should be estimated spatially and temporarily. The Universal Soil Loss Equation (USLE) and USLE-based soil erosion and sediment modelling systems have been developed and tested in many countries. The Sediment Assessment Tool for Effective Erosion Control (SATEEC) system has been developed and enhanced to provide ease-of-use interface to the USLE users. However many researchers and decision makers have requested to enhance the SATEEC system for simulation of soil erosion and sediment reflecting effects of single storm event. Thus, the SATEEC R factors were estimated based on 5 day antecedent rainfall data. The SATEEC 2.1 daily R factor was applied to the study watershed and it was found that the R2 and EI values (0.776 and 0.776 for calibration and 0.927 and 0.911 for validation) with the daily R were greater than those (0.721 and 0.720 for calibration and 0.906 and 0.881 for validation) with monthly R, which was available in the SATEEC 2.0 system. As shown in this study, the SATEEC with daily R can be used to estimate soil erosion and sediment yield at a watershed scale with higher accuracy. Thus the SATEEC with daily R can be efficiently used to develop site-specific soil erosion best management practices based on spatial and temporal analysis of soil erosion and sediment yield at a daily-time step, which was not possible with USLE-based soil erosion modeling system.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.5
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• pp.2187-2196
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• 2011

The objective of this study was to investigate the effect of gait training using rhythmic auditory stimulation on gait symmetry of stroke patients. Forty chronic stroke patients were divided into four groups by intervention. Group A and B received auditory stimulation when they walk with comfortable gait speed. Group A received auditory stimulation to paralyzed side while group B to non-paralyzed side. Group C and D received auditory stimulation with 10% faster gait speed than their comfortable gait speed. Group C received auditory stimulation to paralyzed side while group D to non-paralyzed side. Gait training using auditory stimulation was done in each group during five minutes. Gait symmetry was evaluated by formula and temporal variables of gait were measured by gait analysis system. Step time was decreased significantly in all groups except group A (P<.05), and gait symmetry was also improved significantly in all groups except group A (P<.05). Cadence was increased significantly in all groups except group A (p<.05), but velocity was not increased in all groups. Therefore we conclude that RAS gait training is effective in improving gait symmetry and can be useful to stroke patient's gait training.

• Journal of The Korean Association For Science Education
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• v.30 no.8
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• pp.1017-1030
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• 2010

In this study, an enriched in-service program for teaching scientific creativity was developed and implemented using the scientific creativity activities developed by Park, Park, & Lee (2008). In this program, science teachers performed scientific creativity activities by themselves and practiced the development of actual teaching materials. As a result, science teachers mentioned that they could achieve their goals by learning about various actual teaching materials and teaching strategies for gifted education. They also mentioned that the in-service program was interesting, had appropriate levels of learning difficulty, and that they would apply the teaching programs and teaching strategies to actual gifted education. Observing teachers' actual learning processes during the in-service training course, it was found that they actually participated in the in-service program for a long time intensively and could improve conceptual understanding in depth, but it was necessary to long-term creative thinking practice for being beyond the level of students' creative activities. Finally, from the analysis of teaching materials developed by teachers at the final step of the in-service program, it was found which aspects were developed well or were unsatisfactory, therefore, these findings could be applied for more improved in-service programs.

• Journal of Korean Physical Therapy Science
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• v.8 no.2
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• pp.977-987
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• 2001

The purpose of this study was to examine the effects of sensory integration therapy (SIT) on sensory' motor development and adaptive behavior of cerebral palsy children. The design of this study was quasi experiments with a non-equivalent pre- and post-test control design. Subjects of the study were arbitrarily chosen based on predetermined selection criteria among the cerebral palsy children who were treated as out-patients at two rehabilitation hospitals one in Seoul, and the other in Kyunggi-do. The study was conducted between early April and late July in 2000. Fifteen children were in the experimental group and eleven in the control group. The allocation was done based on ease of experimental treatment. A five-step SIT program was devised from a combination of SIT programs suggested by Ayres(1985) and Finks(1989), and an author-designed SIT program for cerebral palsy children. The experimental group was subjected to 20 to 30 minutes of SIT per session. two sessions a week for ten -week period. The effects of SIT were measured with respect to 9 sub-areas that can be administered to cerebral palsy children out of a total of 17 sub-areas in the Southern California Sensory Integration Test (SCSIT) developed by Ayres (1980). In addition. the scale developed by Russell (1993) for Gross Motor Function Measure (GMFM). and Perception Motor Development Test developed by 中司利一 et al.(1987) were also applied. Adaptive behavior was analyzed using guidelines in two unpublished documents - School-Age Checklist for Occupational Therapy by the Wakefield Occupational Therapy Associates, and the OTA-Watertown Clinical Assessment by the Watertown Occupational Therapy Associates-, and an author-developed Adaptive Behavior Checklist. Collected data were statistically analyzed by SPSS PC for chi square test, Mann-Whitney test, Wilcoxon signed rank test, and paired t-test. The results were as follows: 1. In sensory development, the experimental group exhibited a score increase compared to the control group, but the difference was not statistically significant, Although the experimental group showed improvements in all. 9 sub-areas compared to the control group, only right-left discrimination exhibited statistically significant change. 2. In gross motor development, the experimental group showed improvements in score compared to the control group, but it was not statistically significant. In fine motor development, the experimental group exhibited statistically significant improvements compared to the control group. In sub-area analysis, figure synthesis showed positive change. 3. In adaptive behavior development, post-experimental adaptive behavior scores were higher compared to pre-experimental scores with statistical significance. Furthermore, sub-areas emotional behavior, perception behavior, gross-fine motor function, oral-respiration function, motor behavior, motor planning, and adaptive response exhibited higher scores after SIT. In conclusion SIT was found to be partially effective in sensory and fine motor development, effective in all adaptive behavior areas, and not effective in gross motor development. Thus, this study has shown that SIT is an effective intervention for sensory development, fine motor development, and adaptive behavior for cerebral palsy children. But, for the effectiveness of SIT on gross motor development, further studies employing longer-time experiments are recommended.

• The Journal of Engineering Geology
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• v.27 no.3
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• pp.255-265
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• 2017

We have determined the optimal pumping rate of the PW-2 water well (depth=100 m) at Imgokri, Sangju City. Cutting analysis and geophysical logging data reveal water-producing horizons at 26.1-26.5, 28.0-30.0, 33, 58, and 71 m. For pumping rates of 40, 55, 70, 90, and $132m^3/d$ over 70 days, the estimated drawdown from the PW-2 well was 6.48, 11.56, 18.07, 28.99 and 60.26 m, respectively. During a constant-rate pumping test at a rate of $117m^3/d$, the cone of depression intersected an impermeable boundary after 120-150 min of pumping. Therefore, we consider the critical pumping rate for well PW-2 to be $90m^3/d$. After pumping at $90m^3/d$ for 70 days, the calculated drawdown was 28.82-31.27 m. We suggest an optimal pumping rate for well PW-2 of $70-90m^3/d$, as the optimal pumping rate should be similar to the critical pumping rate. Sharp increases in the slope of the time-drawdown relationship, dissolved oxygen concentrations, and oxidation-reduction potential during the constant-rate pumping test indicate the limited development of bedrock aquifers around PW-2.