• Title/Summary/Keyword: Systematic reduction study

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A systematic review of Korean research trends in dental fear between 2007-2017 (체계적 문헌고찰을 통한 국내 치과공포 연구 동향분석 (2007-2017))

  • Im, Ae-Jung;Kim, Se-Eun;Kim, Hyun-Ji;Park, Deok-Hyun;Park, Min-Young;Park, So-Young;Lee, Dong-Gyun;Hong, Eui-Jeong;Lim, Hee-Jung
    • Journal of Korean society of Dental Hygiene
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    • v.18 no.5
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    • pp.607-620
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    • 2018
  • Objectives: The purpose of this study was to investigate the overall research trends and factors influencing dental fears in the last 10 years (2007-2017) and provide recommendations for future research. Methods: The literature review focused on dental fear research in Korea. Inclusion criteria of selected studies were as follows: studies that examined fear in middle school students or older, studies undertaken between 2007-2017, and studies that examined trends and factors relating to dental fears. Results: Findings from this literature review showed that the most commonly used tool for measuring dental fear was the Dental Fear Survey (DFS). A lack of trust towards the dentist increased dental fear among patients. Women managed fear better than men. Past pain experiences increased dental fear. The most frequent intervention for reducing fear was sound (41.7%). Most of the intervention studies demonstrated a reduction of fear, with the exception of interventions using ear plugs. Fear was increased in studies involving ear plugs. Conclusions: Based on the results of the study, specific measures should be taken to alleviate past pain experiences, such as the fear of anesthetic injections and sensations of the dental drill. Continuous research is needed to reduce dental fear.

A Study of Traffic Noise Characteristics on the National Highways (일반국도의 교통소음특성에 관한 연구)

  • Son, Hyeon Jang;An, Deok-Soon;Baek, Cheolmin;Kwon, Soo-Ahn;Lee, Jaejun
    • International Journal of Highway Engineering
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    • v.15 no.2
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    • pp.11-18
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    • 2013
  • PURPOSES : This study presents the noise level and frequency characteristics investigated in the national highways with the consideration of various measuring conditions and/or methods. METHODS : The noise levels on the asphalt concrete pavement(ACP) and the jointed plain concrete pavement(JPCP) of the national highway were measured and analysed with respect to three variables, i.e., pavement type, surface condition, and measurement distance. The PASS-By method is utilized for the noise measurement and then using CPB spectrum analysis method with 1/3 octave bandwidth, the noise levels and frequency characteristics were calculated for two-second periods before and after the peak noise. RESULTS : Depending on the pavement type, the noise level was changed as the average noise levels are 73.3dB(A) and 78.3dB(A) for ACP and JPCP, respectively. With respect to the effect of surface condition, the average noise levels for crack H(high), M(medium), and L (low) sections are 77.4dB(A), 77.4dB(A), and 78.1dB(A), respectively. Regarding the measurement distance, 1.2meter difference in measuring location reduces 1.6dB(A) of noise level; the average noise levels at 5.3m and 7.5m from the centerline of outer lane are 72.8dB(A) and 71.2dB(A), respectively. It should be noted that the noise levels are slightly different as a function of vehicle speed and type. However, the overall trends for each case was similar. It was found that the domain frequency bands for ACP and JPCP were 400Hz~2000Hz and 500Hz~2000Hz, respectively. CONCLUSIONS : Based on the analysis with the measured noise date from national highway, it was concluded that the noise level and frequency band vary depending on the various conditions. It was also found that some variables significantly affect the noise level while others do not. With further systematic investigation, the comprehensive noise characteristics on the national highway can be achieved. Using such database, it is possible to develop the fundamental noise reduction technology.

Validity and Reliability of Professional Identity of Dental Hygienists (치과위생사 전문직 정체성 측정도구의 타당도와 신뢰도)

  • Kim, Hyeong-Mi;Cho, Young-Sik
    • Journal of dental hygiene science
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    • v.17 no.6
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    • pp.533-542
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    • 2017
  • This study aimed to develop a measure of professional identity for Korean dental hygienists and to analyze the factors and characteristics of professional identity of these dental hygienists. In this study, 890 dental hygienists completed a self-administered survey. The final analysis was conducted with a total of 880 responses, excluding 10 questionnaires with unreliable responses and partial responses. A systematic literature review was conducted to establish the definition of professional identity, while content validity, exploratory factor, confirmatory factor, and reliability analysis were conducted to establish the constructive factors. Descriptive statistics, independent sample t-test, and one-way ANOVA were used to identify the level of each factor. Authors conceptualized the professional identity for Korean dental hygienists and item generation, item reduction, and questionnaire formatting. The developed measure of professional identity for dental hygienists consisted of five factors, with 15 items. "Sense of calling," "need for academic capacity building," "performance of delegated authority," "compliance of code of ethics," and "usage of professional organizations" were the constituent factors. Based on these factors, the level of professional identity was the highest in the "performance of delegated authority" and lowest in the "usage of professional organizations." These finding indicated that dental hygienists with higher education levels have higher professional identity levels. The dental hygienists working at the general/university hospital had the highest level of professional identity. Thus, further research is needed to establish a model that consists of factors affecting and influencing the professional identity of dental hygienists.

A Quantitative Risk Analysis of Related to Tower Crane Using the FMEA (타워크레인의 정량적 위험성 평가가법에 관한 연구(FMEA 기법 위주))

  • Shim, Kyu-Hyung;Rie, Dong-Ho
    • Journal of the Korean Society of Safety
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    • v.25 no.6
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    • pp.34-39
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    • 2010
  • The purpose of this study is to suggest objective evaluation model as a plan to utilize as opportunity in establishing judgment standard of mutual inspection criteria and to upgrade inspection ability by reviewing and analyzing level of danger and importance in advance based on inspection results of inspection institutions regarding tower cranes used in construction fields. Tower crane is a mechanical device transporting construction supplies and heavy materials to places over 20~150M high from the ground for the period ranging from a short time of 2~3 months to two years after being installed in construction sites in vicinity of buildings or structures and is an important facility indispensable for construction sites. However, since use period after installation is short and professional technical ability of technicians working on-site about of tower crane is poor, systematic and quantitative safety management is not carried out As a part of researches on procedure of RBI(Risk Based Inspection) possible to apply to Knowledge Based System based on knowledge and experiences of experts as well as to tower cranes for solving these problems, quantitative RPN(Risk Priority Number) was applied to RPN utilizing technique of FMEA(Failure Mode and Effect Analyses). When general RBI 80/20 Rule was applied parts with high level of risks were found out as wire rope, hoist up/down safety device, reduction gear, and etc. However, since there are still many insufficient parts as risk analyses of tower crane were not established, it is necessary for experts with sufficient experiences and knowledge to supplement active RBI techniques and continuous researches on tower cranes by sharing and setting up data base of important information with this study as a starting point.

A Study on Resisitance Performance of the Straight-Framed V-Bottom Hull Forms with High Displacement-Length Ratio (고(高) 배수량일장(排水量一長) 비(比) V-형(型) 직선늑골선형(直線肋骨船型)의 추진저항성능(推進抵抗性能)에 관(關)하여)

  • Kyu-Jong,Cho
    • Bulletin of the Society of Naval Architects of Korea
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    • v.6 no.1
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    • pp.25-34
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    • 1969
  • From viewpoints of over-all ship economy the straight framed V-bottom hull forms with chines are considered to be attractive even for usual commercial vessels, because increments of resistance over that of round hull forms, if any, can be well compensated with reduction in construction cost.[1] To investigate the influences of both prismatic coefficient and chine elevation on resistance performance, three models of straight-framed V-bottom hull forms which are similar to Prof. C. Ridgely-Nevitt's W-18, W-8, and W-20[2],[3] in size and hull form coefficients were tested at the SNU Ship Model Towing Tank for resistance measurements. They are of Cp=0.60, 0.65 and 0.70 and of ${\Delta}/(0.01L)^3=300$. Influence of variation of chine elevation on resistance performance were observed with the test results obtained at normal condition, and at the trimed by the stern by 2% and 4% of $L_{bp}$ at normal condition under same displacement. The hull form characteristics are shown in Table 1, and in Fig. 1, 2, 3, 4 and 5. The test results are shown in Fig 8, 9 and 10 in the form of Cr vs. $V/\sqrt{L}$ curves taking Cp as a parameter for normal condition, trim by the stern in 2% and 4% $L_{bp}$ at normal condition , respectively. Cr vs. $V/\sqrt{L}$ curves taking trim condition as a parameter are also shown in Fig 11, 12 and 13 for Cp=0.60 and 0.70, respectively. The best and the worst trim condition at given $V/\sqrt{L}$ in viewpoint of Cr are plotted for each Cp-value as shown in Fig 14, 15 and 16. From the above results the following conclusions are derived: (1) In general, the resistance performance of the straight-framed V-bottom hull forms are not inferior to those of round hull forms. At a certain range of $V/\sqrt{L}$ the former gives less resistance than the latter. (2) Regarding influences of Cp on Cr, it is observed that, at $V/\sqrt{L}$ less than about 0.925, the greater Cp-value gives the more increment of Cr, and that, at $V/\sqrt{L}$ greater than about 0.925 the smaller Cp-value gives the more increment of Cr. It is also noteworthy that the model of Cp=0.70 has remarkable hump on Cr vs. $V/\sqrt{L}$ curve between $V/\sqrt{L}=0.80$ and 0.90. (3) For higher speed within the test range, the chine elevation having the steeper slope around bow and the easier slope around amidship and stern, refered to watering, give the better results in resistance performance. (4) Assuming the chine elevations adopted for the tested models were not of the best, we would expect further improvement of resistance performance for such form. Hence, a systematic study on chine elevation is very disirable to prepare design data of general purpose for the such hull forms.

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Effects of Urban Greenspace on Microclimate Amelioration, $CO_2$ Sequestration and Eire Obstruction (도시녹지의 미기후개선, $CO_2$흡수 및 화재방지의 효과)

  • ;Yoshiteru Nojima
    • Korean Journal of Plant Resources
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    • v.13 no.3
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    • pp.162-170
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    • 2000
  • This study quantified the effects of urban greenspace on microclimate amelioration and atmospheric $CO_2$ reduction for several residential districts selected in Korea and Japan. The study also explored fire obstruction by urban trees to develop systematic planting guidelines. Transpiration by a Zelkova serrata tree (diameter at breast height: 15 cm) in a day of August equaled cooling effect of about 3 air conditioners running for 12 hours. Average air temperature for the growing season was 0.5$^{\circ}C$ and 1.2$^{\circ}C$ cooler, respectively, in districts with 12% and 22% cover of woody plants than in a district with no vegetation. Annual $CO_2$ uptake and $O_2$ production by woody plants were 3 times greater in a district which was 2 times higher in their cover. Woody plants played, in a district with their 22% cover, an important role through offsetting total $CO_2$ emission from the district by about 3% annually, and through producing 10% of annual $O_2$ requirement by all residents within the district. Appropriate planning strategies of residential greenspace, including species selection, planting layout, greenspace enlargement, and maintenance were suggested to improve microclimate amelioration, air purification, and fire obstruction.

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A Study for Enhancing Disaster Operations Management at Seoul Emergency Operations Center - Focused on the Education and Training for Firefighters of Seoul (서울종합방재센터 상황실 재난상황관리능력 제고 방안 - 서울특별시 소방공무원 교육훈련을 중심으로)

  • Park, Soonil;Park, Chanseok
    • Journal of the Society of Disaster Information
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    • v.14 no.4
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    • pp.480-491
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    • 2018
  • Purpose : This study aims to suggest social support composed of organizational support and managerial support would be systematically managed to enhance Disaster Operations Management at Seoul Emergency Operations Center. Method : Emotional labor was used as an independent variable, and organizational commitment was used as a dependent variable to analyze the mediating effects of social support. Results : First, in the aspect of organizational support, the objective evaluation of disaster situation management, disaster situation management emotional labor reduction education and training program development, monitoring of disaster situation management, quality improvement and work imbalance mitigation of firefighters, and emergency coordination managers are needed for systematic work management for emotional labor settlement. Secondly, it is necessary to select competent firefighters in the level of managerial support, to prepare healing measures for structured phased emotional labor for firefighters, and to have counseling competency for managers for emotional labor firefighting officers. Conclusion : In order to improve disaster management ability, education and training programs should be developed to improve organizational commitment based on social support.

The Principles of Total Quality Management(TQM) and Its Implementation. (총체적 질관리(Total Quality Management)의 이론적 배경과 그 적용실태)

  • Kang, So-Young
    • Journal of Korean Academy of Nursing Administration
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    • v.1 no.2
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    • pp.388-407
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    • 1995
  • This study is (a) to describe the history of Total Quality Management (TQM) generated in the industry, health care service, and nursing society ; (b) to define the concept, total quality management including the definition of quality ; (C) to explain the each principle of TQM theory developed by main theorists, E. Deming, J. Juran, and B. Crosby ; (d) to give the examples related to TQM implementation at the health care organization ; and (e) to mention the extent to which the health care organizations are able to evaluate their cultural organization toward TQM and have had the way to measure the effect of TQM implementation. TQM referred to Continuous Quality Improvement(CQI), Quality Improvement(QI), and Total Quality Improvement(TQI), was not recognized by experts in the United States industry, but by economists in Japan until the end of the 1970's. However, the United States' government led to introduce the principles of TQM to general industry as well as health care service area so that TQM became a main philosophy to manage the organizations in health care service. TQM is a structured, systematic process for creating organization-wide participation in planning and implementing continuous improvement in quality. E. Deming established the "Chain reaction in Quality" and the fourteen point of TQM. The Chain reaction in quality is to describe the relationship among the reduction of waste, rework, and delay, quality improvement, customer satisfaction, and productivity. There are fourteen points to explain the principles of TQM by E. Deming. Juran defined the "Quality Trilogy" to improve the level of quality in any organization. Quality Trilogy has three steps such as quality planning, quality control, and quality improvement for implementing the TQM projects. Crosby describes his TQM theory by establishing "Four Absolutes" and "Fourteen steps in TQM" implementation. Until now, most healthcare organizations have made efforts to organize the TQM task team and to implement TQM principles with various issues. There are three priorities to select the TQM issues : High-volume, High-risk, and Problem-prone. However, there is no absolute, credible measurement yet to evaluate the effects of TQM implementation in health care organization regardless of the classification of health care organizations, geographical background, and social influence. Thus, developing the evaluation way in terms of TQM is the foremost task in health service area. The most important thing for TQM implementation in the organization is to settle up the concept, cultural transformation from traditional management toward quality.

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Acoustic Emission Monitoring of Incipient Failure in Journal Bearing Part II : Intervention of Foreign Particles in Lubrication (음향방출을 이용한 저어널 베어링의 조기파손감지(II) - 윤활유 이물질 혼입의 영향 및 감시 -)

  • Yoon, Dong-Jin;Kwon, Oh-Yang;Jung, Min-Hwa;Kim, Kyung-Woong
    • Journal of the Korean Society for Nondestructive Testing
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    • v.14 no.2
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    • pp.122-131
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    • 1994
  • Journal bearings in the rotating machineries are vulnerable to the contamination or the insufficient supply of lubricating oil, which is likely to be the cause of unexpected shutdown or malfunction of these systems. Various destructive and nondestructive testing methods had been used for the reduction of maintenance cost and the operational safety problems due to the accidents related to bearing damages. In this experimental approach, acoustic emission monitoring is employed to the detection of incipient failure caused by intervention of foreign particles most probable in the journal bearing systems. Experimental schedules for the intervention of foreign particles was composed to be more quantitative and systematic than last study in consideration of minimum oil film thickness and particle size. The experiment was conducted under such designed conditions as inserting alumina particles to the lubrication layer in the simulated journal bearing system. Several parameters such as AE rms level, waveform, AE energy distribution and other AE event parameters are used for analysis and characterization of damage source. The results showed that the history of damage was well correlated with the changes of AE rms level and the type of damage source signal can be verified using other informations such as waveform, distributions of AE parameters etc.

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A Comparative Study on the $CO_2$ Storage Method ($CO_2$ 해양처리방안 비교연구)

  • Jung, R.T.;Kang, S.G.;Kang, C.G.;Park, Y.C.;Yoon, C.H.
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.8 no.3
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    • pp.111-115
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    • 2005
  • The concentration of atmosphere carbon dioxide ($CO_2$) which is one of the major greenhouse gas, continues to rise by the increase in fossil fuel consumption, forest destruction and decrease of biological diversity, etc. In order to weaken the global warming, a reduction of $CO_2$ discharge to the atmosphere is required. The $CO_2$ ocean sequestration technology utilizes the intrinsic oceanic capacity of $CO_2$ absorption, diluting and/or dispersing the liquefied $CO_2$ in the deep ocean (>2,000 m). This geo-engineering approach is regarded as one of the occasions to mitigate the $CO_2$ concentration in the atmosphere. Some developed centuries such as Japan, USA, Norway, etc. have intensively carried out the projects on the research and development of $CO_2$ ocean sequestration since 1990s. There have been several approaches to develop the relative technological system to mitigate the increasing $CO_2$, however, there was no systematic and practical R&D programme in the $CO_2$ ocean sequestration. This paper has described the state of the art on the three optional methods of $CO_2$ sequestration, and compared with them in the aspect of the applicable possibility.

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