• The Journal of Advanced Prosthodontics
• /
• 제10권4호
• /
• pp.259-264
• /
• 2018

PURPOSE. The purpose of this study was to evaluate the effect of the zirconia surface architecturing technique (ZSAT) on the bond strength between veneering porcelain and zirconia ceramic. MATERIALS AND METHODS. 20 sintered zirconia ceramic specimens were used to determine the optimal surface treatment time, and were randomly divided into 4 groups based on treatment times of 0, 1, 2, and 3 hours. After etching with a special solution, the surface was observed under scanning electron microscope, and then the porcelain was veneered for scratch testing. Sixty 3 mol% yttria-stabilized tetragonal zirconia polycrystal ceramic blocks were used for tensile strength testing; 30 of these blocks were surface treated and the rest were not. Statistical analysis was performed using ANOVA, the Tukey post-hoc test, and independent t-test, and the level of significance was set at ${\alpha}=.05$. RESULTS. The surface treatment of the zirconia using ZSAT increased the surface roughness, and tensile strength test results showed that the ZSAT group significantly increased the bond strength between zirconia and veneering porcelain compared to the untreated group (36 MPa vs. 30 MPa). Optimal etching time was determined to be 2 hours based on the scratch test results. CONCLUSION. ZSAT increases the surface roughness of zirconia, and this might contribute to the increased interfacial bond strength between zirconia and veneering porcelain.

• 보건의료산업학회지
• /
• 제6권4호
• /
• pp.191-204
• /
• 2012

The purpose of this study was to provide basic data necessary for improvement by closely examining factors of having influence upon dental technicians' turnover. Questionnaire survey was conducted of 204 dental technicians who work at dental hospitals, clinics and dental laboratory rooms in Daegu area. The following conclusions were obtained. The satisfaction with job was high in job position in more than co-representative, in the whole and other task, and in less than 9 hours as for working hours. In the satisfaction with working environment, dissatisfaction was high in women, in the working career with 7~9 years, in chief level as for the job position in charge, in being responsible for porcelain in case of the duty field, and in more than 10 people as for the number of employees. The higher satisfaction with job satisfaction and working environment led to the lower turnover intention. Turnover intention was low in case of having ventilation fan & dust collector desk and in case of being well ventilated inside the workshop. As the above results, it is considered to be necessary for arranging institutional device of protecting dental technicians' health and reducing turnover through improving working environment such as forming comfortable environment of using the dust-collecting facilities and the ventilation facilities, wearing suitable individual protective gear and arranging the rest space.

• 항공우주의학회지
• /
• 제30권2호
• /
• pp.51-53
• /
• 2020

In commemoration of Vol. 30, Issue 2, our journal prepared three review articles, two original papers, and a case report. The first review analyzed aircraft accidents caused by pilots' fatigue and presented a protocol to measure their fatigue, such as primary background survey, subjective drowsiness/arousal evaluation, sleep and activity log, sleep data, and performance measurement. The second review analyzed shift work patterns and work characteristics that may affect the fatigue of aviation mechanics. Also, desirable work principles for aviation mechanics (restrictions on working hours, appropriate rest hours, and night shift restrictions) were presented. The third review discussed the effects that allergic rhinitis can have on pilots (drowsiness and decreased arousal) and introduced a safe treatment method that can prevent these adverse effects. In the first original article, the ratio of 'incompatible (non-fit)' result in aerospace medical examination among Korean aircraft pilots for the past five years was investigated by age group and the common causes of nonconformity were analyzed. In the second original article, the prevalence, mortality, prevalence according to age groups, and regional characteristics of severe febrile thrombocytopenia syndrome were compared and analyzed in Korea and Japan for the past five years. Finally, in the case report, the cases of a patient diagnosed as gastrointestinal stromal tumors who received surgical treatment and chemotherapy were discussed, and the results of the judgment were presented.

• 한국화재소방학회논문지
• /
• 제28권2호
• /
• pp.98-104
• /
• 2014

소방공무원의 열악한 근무조건을 개선하기 위해서 2004. 6. 1. 소방 방재청 출범과 함께 3교대 근무체제가 제시되었다. 그러나 차일피일 미루어 오다 2008. 12. 행안부장관이 2012년까지 3교대 전면시행을 보고하면서 이듬해 2009년부터 3교대 근무가 시범 실시되었고, 이후 2013년 6월 현재 약 97%의 시행률을 보이고 있지만, 지방재정 열악 등으로 2014년에 완료되는 것으로 알려지고 있다. 한편, 소방공무원 3교대 근무형태에 관한 국내연구는 거의 전무한 실정으로 아주 초보적이고 유치한 수준으로 이제 시작에 불과한 단계라 할 수 있다. 따라서 본 연구는 그동안 시행해 오고 있는 3교대 근무 시행의 문제점과 선결과제 등을 살펴보고, 향후 3교대 근무제의 실효성 확보를 위한 몇 가지 정책적 제언을 하는데 그 목적이 있다.

• 한국치위생학회지
• /
• 제4권2호
• /
• pp.265-276
• /
• 2004

The purpose of this study,was to find out health status, characteristics related to working conditions, occurrence of low back pain and its related factors among dental hygienists working in dental clinics, and, thus, to provide basic information necessary to set up some plans for preventing the occurrence of low back pains and improving working conditions for dental hygienists. The data were collected from 310 dental hygienists working at dental clinics in Pusan and Kyungnam area, including Masan, Changwon, Jinhae and Jinju, with a self-administered questionnaire and were analyzed finally for 295 records with SPSS for Windows(7.52K) program. The results were as follows : Working condition was considered to be fair by 562% of dental hygienists were thought to threaten their health in the dental clinics. About seventy percent of dental hygienists worked over ten hours a day and 72.8% were standing while working over 7 hours, 65% considered working hours too long. Health status was thought be more than average for 82.3% while more than half perceived certain degree of stress frequently. The rate of complaining low back pains among dental hygienists was 87.8% with pains more than medium level for 39.3%. The variables significantly related to the degree of low back pains were height, uncomfortable postures, type of working postures and the height of working table, while some variables including height, hours of working on the feet, the presence of hazardous work environment, uncomfortable postures, the presence of hazardous works, the amount of working hours, type of working postures and work-associated stresses, were significantly related to the number of symptoms for low back pains. Multiple regression analysis showed that occurrence of low back pains was significantly influenced by 5 factors such as subjective status of health, work-related stresses, the degree of perception to work environment, the degree of perception to the amount of working hours and age. In conclusion, it might be necessary to manage working conditions effectively by reducing working hours, making good postures while working and removing stressful conditions in order to reduce risk factors for the occurrence of low back pains among dental hygienists. Therefore good working postures, assignment of appropriate rest time and some programs for early detection, care and education of low back pains should be provided for the dental hygienists.

• 보건교육건강증진학회지
• /
• 제12권1호
• /
• pp.111-127
• /
• 1995

This study was designed to investigate the relationships between children's physical growth and health and their raising conditions and to find out the important conditions to improve their physical growth and health. The rasing conditions were classified into three major parts; i. e., family conditions, conditions of nutrition up-taking, and conditions of rest or sleep and exercise or play. Then, the questionnaire including the items to survey these three areas of raising condition and the items to evaluate the health status were given to children' mothers or fathers and filled up by them. The data of their 4 anthropometric measures; body weight, stature, sitting height and chest girth, were also collected from their latest records of health examination. The data of health status were converted to health scores representing 6 domains of health; digestive organs, respiratory organs, auto-nerve systems, fatigue, others and health as a whole. Then, correlations of raising conditions were determined with four antropometric measures and 6 health scores as criterion variables. Then, number of families to live together, and child's birth order in the domain of family conditions, habits of unbalanced diet, eating frequency of eggs, fruits, green and yellow vegetables, light colored vegetables, milk products in the domain of nutrition up-take, and the time for study at home, the place for play, the number of friends to play with together, the hours for playing out of door, the hours for playing sports, and the hours to move their body for assisting house keeping were picked out to investigate their relationships with physical growth and health status. Then, their habits of unbalanced diet and eating frequency of eggs, green or yellow colored vegetables, and milk products were found more influential conditions and more over, birth order, the time for study at home, the time to play out of door showed moderate degree of connection with physical growth and health status in early childhood.

• 한국보건간호학회지
• /
• 제19권2호
• /
• pp.359-370
• /
• 2005

The purpose of this study is to provide basic data for prevention of VDT syndrome by confirming VDT syndrome according to the type of computer use. The subjects recruited for the research were 518 students who were in the 4, 5, 6 grades from 5 schools in Seoul. The data were collected during the period from October 8 through October 18, 2004. The results were as follows; 1. The mean value of the VDT syndrome was 1.55 (SD=.52) for the 5th graders. 2. The degrees of VDT syndrome according to the characteristics of the subjects shows higher scores for the 5th and 6th graders, boys, students with more than 4 online friends, students with a low degree of school life satisfaction, and for students with parents who had a negative attitude for their children. 3. The degree of VDT syndrome according to the type of computer use showed higher scores when the students used computers for game more than for study, more than 11 hours in a week, more than 2 hours at one time, not having any rest, in dark places, with the monitor less than 40 an distance from the eyes, sitting with their legs crossed and when the keyboard was in a higher position than their elbows. The internet absorbed group showed higher scores than the unabsorbed group. 4. There was positive correlation between the hours of computer use and VDT syndrome. Also, internet addiction and VDT syndrome had positive correlation. Therefore, each home and society needs to pay consistent attention to correct computer use by their students. Especially, schools will have to educate about computer utilization and VDT syndrome.

• 수산해양교육연구
• /
• 제5권1호
• /
• pp.23-30
• /
• 1993

The Korea Seaman's Act is providing that fishermen s salaries are exceptionally defined and working hours and paid leave are not defined at all. Significant problems of Fishermen's Labor Condition are, (1) It is hard to guarantee the basic right of fishermen as their wages are variable depending on the catch. (2) Excessive working hours would hamper the labor reproduction ability and increase the frequency of disaster. (3) Moreover, fishermen have to search for a new job following the lay off after working aboard during the period defined by contract. The possible implement of Seamen's Act are : (1) The wage system must be unified by regular wages. If it is hard to perish the lay system its relative importance should be diminished whereas the fixed minimum wages and the allowance depending on the position and working days should be paid. (2) This discrimination of the fishing vessels from merchant should be eliminated by removing the item on the Act which excludes the fishermen on the working hours. If it is hard to do so practically the lower regulations defining the maximum periods of duty and minimum periods of rest for fishermen must enact separately as in Japan and England. (3) The difference in the provisions of paid leave between the merchant seamen and fishermen must be abolished (4) It is the most desirable to improve the fishermen's labor conditions through the completion of the Act. However, before doing this, the employers and employees must try to solve the problems through the collective agreement by themselves.

• 한국산업보건학회지
• /
• 제22권2호
• /
• pp.107-118
• /
• 2012

Objectives: This study examines the occurrence of disease resulting from low back pain and factors of working environment meaningfully influencing the occurrence of lumbago as well as analyzes '2nd Korean Working Condition Survey (KWCS)' conducted in 2010 so as to establish the prevention and improvement measures. Methods: The analysis method is that it is to compare the prevalence rate of low back pain according to working environment via odds ratio and to implement the test about the factors having the difference in working environment between low back pain group and normal group through weighted t-test. Results: As a result, it indicates that there is a meaningful difference for prevalence rate of low back pain according to age, status in employment and education level which are socio-demographical factors. The analysis in working hours shows that the period of work is a factor raising the prevalence rate of low back pain rather than weekly working hours. The analysis in the work risk factor indicates that the increase in prevalence rate of low back pain takes place to either workers with repetitive movement and continuously standing posture or those with heavy stress and emotional labour. Conclusions: Workers with low back pain have suffered from accident, depression, anxiety disorder and sleep. The factors in which the prevalence rate of low back pain decrease are to provide information on health and safety and working speed, and enough rest.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• 제13권8호
• /
• pp.4315-4328
• /
• 2019

The present study investigated the effects of work satisfaction on quality of life for 119 paramedics, the Korean equivalent of 911 paramedics. Data collection began in July 2017 and lasted for six months. Data was collected from 410 119 paramedics of the J province and the G metropolitan area who consented to study participation. The results showed that the higher the job satisfaction of the participants, the higher the quality of life (r = 0.508, p = 0.008). The factors affecting the quality of life were leisure activity, subjective health, and job satisfaction. For 119 paramedics to improve their quality of life, they need to relieve work stress and fatigue through leisure activities, and recover and maintain their health through sufficient rest. Moreover, returning to work in a healthy state likely leads to increased job satisfaction, and the quality of life will increase accordingly. Therefore, 119 paramedics should be permitted to have plenty of leisure time outside their work hours and should be able to maintain health through periodic health checks.