• Transactions of the Korean Society of Mechanical Engineers A
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• v.41 no.7
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• pp.655-663
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• 2017

With the development of ICT technology, the indoor utilization of robots is increasing. Research on transportation, cleaning, guidance robots, etc., that can be used now or increase the scope of future use will be advanced. To facilitate the use of mobile robots in indoor spaces, the problem of self-location recognition is an important research area to be addressed. If an unexpected collision occurs during the motion of a mobile robot, the position of the mobile robot deviates from the initially planned navigation path. In this case, the mobile robot needs a robust controller that enables the mobile robot to accurately navigate toward the goal. This research tries to address the issues related to self-location of the mobile robot. A robust position recognition system was implemented; the system estimates the position of the mobile robot using a combination of encoder information of the mobile robot and the absolute space coordinate transformation information obtained from external video sources such as a large number of CCTVs installed in the room. Furthermore, vector field histogram method of the pass traveling algorithm of the mobile robot system was applied, and the results of the research were confirmed after conducting experiments.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.27 no.4
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• pp.352-360
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• 2017

Objectives: This study aimed to determine the effects on musculoskeletal symptoms of both social demographic features and detailed characteristics of each task category of care workers who offer visiting home-help services. And to establish the measures that can reduce musculoskeletal symptoms among care workers. Methods: This study was conducted among 192 care workers from welfare centers C and K located in city P. After participants completed the task burden checklist regarding the scale of musculoskeletal symptoms and the details of their duties, the data collected were analyzed using the SPSS 21.0 program. Results: According to the degree of observable musculoskeletal symptoms in care workers, the highest figures were observed for back and shoulder pain. Based on the results of assessing the effect of detailed task category characteristics on musculoskeletal symptoms, "helping patients eat, helping patients move, helping patients bath, and changing body positions" were found to have an effect from the physical care category, "providing physical therapy assistance, treating bedsores" from the health care category, and "cleaning and doing laundry" from the facility management category. Conclusions: Due to the high proportion of patients requiring burdensome physical labor from care workers such as moving patients who have trouble doing so on their own, helping them change positions, and so on, it is highly likely that pain will occur in the low back, which carries most of the physical weight. So, education on human epidemiological positions that can reduce overload on areas prone to pain such as the low back and shoulders is essential. Proper equipment and personnel support must be provided for dangerous tasks. Further, multidimensional social support is required consistently.

• Environmental and Resource Economics Review
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• v.17 no.1
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• pp.165-196
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• 2008

This paper reports a quantitative meta analysis of the economic impacts of localized noxious and contaminated sites. Using either hedonic property value or stated preference methods, economists have studied the effects of contamination or noxious activities, or the benefits realized from their elimination, on real estate prices at more than 40 sites. In support of wise public and private investments in environmental quality, most of these studies aim to inform decision makers about the benefits of remediation and cleanup. Their results vary considerably, but there has been no previous systematic effort to analyze the differences and identify shared insights. This study uses established methods of meta analysis to identify points of agreement and differences in this body of literature. The studies are characterized by the type of site, modeling approach, geographic extent of impacts, data features, and other key factors that underlie their value estimates. The impact estimates are normalized as proportional effects on property values. This study attempts to discover whether the estimated economic impacts of contamination or noxious activity differ according to these characteristics of the studies, and whether anything general can be said about the economic consequences of site contamination and remediation. Bivariate, multivariate, and logit techniques are applied to the data. The results suggest that the property value is the most sensitive to water base contamination, published case studies result in systematically greater environmental value than those in unpublished reports, and real estate markets show responses to environmental condition changes.

• Journal of the korean academy of Pediatric Dentistry
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• v.42 no.3
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• pp.226-232
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• 2015

Critical pathway (CP) defines the optimal care process, sequencing and timing of intervention by multidisciplinary health care teams for a particular diagnosis and procedure. The aim of the study was to evaluate the clinical usefulness and the satisfaction of patients and dental staff after implementation of a critical pathway for the dental treatment of disabled children and adolescents under conscious sedation. Thirty patients are divided in two groups (Pre-CP and CP) at the department of Pediatric Dentistry of Pusan National University Dental Hospital. The satisfaction levels of patients/guardians and the staff members were collected by survey questionnaire. The parents' satisfaction was significantly improved after the implementation of CP. Also, medical/dental staff members were highly satisfied with its usefulness. The application of a critical pathway for disabled children and adolescents might be useful and improve the satisfaction of the parents and medical/dental staff members.

• Journal of Aerospace System Engineering
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• v.11 no.5
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• pp.36-41
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• 2017

As the space debris in the satellite orbit increases, the risk of collision between the currently operating satellites and the space debris is continuously increasing. Therefore, in this study, we designed one-degree-of-freedom capture device using simple deployment mechanism. The capture device consists of four link groups connected with net. To increase the reliability, each link group is connected to one driving part so that the total degree of freedom is 1. In addition, the links were stowed on each side of the satellites so that they would not affect the janitor satellite mission. Finally, to confirm the possibility of deployment in the space environment, we carried out deployment experiments in water similar to the microgravity environment, and confirmed the deployment of capture device and the possibility of capturing target satellite.

• Journal of Digital Convergence
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• v.11 no.1
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• pp.1-11
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• 2013

This study attempt to explore how much characteristics of personal and institutional of staffs in shelter for teenage runaway influence to client's violence, and which factor of them are relative to client's violence. For this aims, we carried out a survey, survey subjects in shelter for teenage runaway participated in this research. T-test and variance analysis attempted to compare degree of violence experience of respondents by personal and institutional characteristics. According to result of analysis, age in the midst of personal characteristics is meaning difference and duty-time and type of shelter in the midst of institutional characteristics revealed meaning difference. Next, Multi-regression analysis tried to explore relative factor influencing on client's violence. The results, age in the midst of personal characteristics is relative with physical violence, duty-year in present institution is relative with etc harm. Also, duty-time per week of institutional characteristics is relative all with four type of violence. Type of shelter is relative with property harm, emotional violence and etc harm. Counseling time during duty is relative with physical violence. Above results provide basic data to find ways preventing client's violence to staffs in shelter for teenage runaway.

• Clean Technology
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• v.18 no.4
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• pp.440-445
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• 2012

15 carbon footprint product (CFP) schemes, including Korea Carbon Footprint Label, UK Carbon Trust's Carbon Reduction Label and Japan CFP are implemented in the world. A CFP describes green house gases (GHGs) emissions emitted throughout product's life cycle and is intended to reduce GHGs emissions by labeling a CFP result on product. This study calculates Korea, UK and Japan CFP result of vacuum cleaner, detergent, packagin material in order to analyze the Korea, UK and Japan CFP standards. Our results demonstrate significant differences among then calculated results because of criteria, emission factors, etc. Therefore, there are many difficulties in providing various CFP results and the international standard and guidelines for product category are needed.

• Fire Science and Engineering
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• v.34 no.3
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• pp.76-84
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• 2020

Most outlet fires occur around plug pins and plug pin receivers. However, no research has been conducted on ignitions at power connection points. This study confirms the possibility of ignition after incomplete connection, using a stranded wire, to the power connection point of an outlet. The experiment was divided into basic and reproducing experiments. The basic experiment confirmed the possibility of ignition according to the number of wire strands connected to the power connection point, and it identified the characteristics of the residue after the fire. In the reproducing experiment, lamps, vacuum cleaners, and heaters were connected to an outlet to check if the ignition at the connection advanced into a fire. The fire advanced due to the heat and arc generated at the connection point, and partial losses were identified in the U-type holder and clip. Accordingly, the results demonstrate that a fire may occur when the stranded wire is incompletely connected to the outlet. Moreover, it was confirmed that the cause of a fire can be determined based on the characteristics of the residue.

• Journal of Korea Water Resources Association
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• v.53 no.11
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• pp.1015-1024
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• 2020

Recently, water pollution accidents have continued to occur in pipelines such as red water Incheon and Seoul. In order to recognize this water quality problem, it is necessary to install a water quality sensor in an appropriate location and measure it in advance to detect or block the water supply to the water faucet of the shelter. However, there are limitations, such as maintenance costs, to installing multiple water meters in all pipelines. Therefore, this study proposed a methodology for determining and prioritizing the installation location of flow-based water quality sensor for the recognition of water quality problems in pipelines. We applied the proposed procedure to the pipe break scenario. The results of the determination of the location of the water quality sensor were presented by applying it to the pipe network that actually operates the emergency pipe in Korea. The result of the decision showed that in the event of abnormal situation caused by the destruction of individual pipes, the flow rate of the pipes around the aqueduct and the tank may change rapidly, resulting in water quality accidents caused by turbidity. In the future, it is expected that the water quality monitoring point selection method, such as establishing an external pipe operation plan for pipe cleaning, will utilize the procedure for determining the location of the water quality sensor according to the velocity.

• Journal of Chest Surgery
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• v.34 no.4
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• pp.338-344
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• 2001

배경: 말기 신부전 환자에서 심장병, 특히 관상 동맥 질환의 이환이 늘어나면서 관상동맥 우회수술의 대상 환자가 지속적으로 증가하고 있다. 이들 환자군은 수술후 유병률과 사망률이 매우 높고 고위험군으로 알려져 있다. 대상 및 방법: 1996년 3월부터 2000년 5우러까지 서울 중앙 병원 흉부외과에서 술전 말기 신부전증으로 진단 받은 후 관상 동맥 우회수술을 시행받은 환자 25명을 대상으로 의무 기록을 중심의 후향적 분석을 하였다. 술전 위험 인자 및 술전 신기능, 수술 결과, 술후 경과, 수술후 합병증, 사망률 및 생존률 등을 분석하였다. 결과: 술전 평균 크레아티닌 청소율은 12.7$\pm$5ml/mim였고 술전 평균 혈중 크레아티닌 치는 6.2$\pm$3mg/dl(1.7-14.4)였다. 술전 투석을 시행중인 환자는 11례(44%)였고 술전 투석을 시행하지 않았던 14례(56%)중 8례(8/14, 57.1%)는 수술전후로 새로이 투석이 필요하였다. 술전 혈액 투석 중이었던 9례중 2례에서 수술후 복막 투석으로 전환하였다. 수술 사망률은 2례(8%)로 흡인성 폐렴과 종격동염으로 1례, 그리고 수술후 출형과 종격도염으로 1례가 사망하였다. 수술후 합병증은 14명(56%)의 환자에서 발생하여 매우 높은 발생율을 보였다. 만기사항은 2례(8%)에서 발생하였으며 사망원인은 카테터에 의한 복막염이었다. 생존 환자의 4년 생존률은 82$\pm$13% 였다. 결론: 말기 신부전 환자에서의 관상동맥 우회수술을 비교적 만족스러운 범위의 수술 사망률(8%)을 보였으나 합병증 발생률이 매우 높고 합병증 발생 시 사망률이 매우 높아 수술주위 감염 예방과 세심한 환자 관리가 필요하다.