This study was conducted to find out the degree of tiredness, accumulated tendencies of fatigues in accordance with 3 types of circadian rhythms and 3 types of perceived fatigue signs such as physical, psychological and neurosensory aspects in before and after work at night. Samples were chosen from the 217 intensive care units nurses working in 13 general hospitals which had 3 shift rotating systems, Data were collected from November to December in 1999. Two hundreds seventeen respondents were classified by 3 circadian types such as 59 morning, 110 middle and 48 evening. Circadian type was measured by the circadian type scale which was designed by ${\ddot{O}}stberg$ and Home (1976). in order to estimate the level of tiredness, the investigator used the fatigue checklist designed by the Labor and Health Institute of Japan(1970). Analysis was done by frequency a percentages, ${\chi}^2$ test and repeated measures ANOVA test. The result of this study were as follow: 1. In the general characteristics of the subjects circadian types, moderate type had the large proportion at 50.7% and morning type had 27.2% and evening type had 22.1%. 2. According to the 3 types of fatigue signs, the highest general tendency was 'General weakness' and 'Feeling of headsore' for physically perceived sign, 'Drowsiness' for psychological sign, and 'Uncomfortableness in sight seeing' for neurosensory sign. 3. The most frequently complained fatigue were observed in physical symptoms among physical, mental, and neurosensual symptoms. The percentage of complained was higher after night work than before the work started. 4. There was not any statistical significant difference between the circadian type and the degree of physical, mental, neurosensory fatigue. 5. There was not any statistical significant difference in regarding to each date of night shift except difference between 1st and 2nd days of fatigue perceived physically. Therefore, the study concluded that the fatigue perceived by night shift nurses might be related with shift working condition rather than circadian types.
Park, Young-Nam;Yang, Hye-Kyeong;Kim, Hyunli;Cho, Young-Chae
Korean Journal of Occupational Health Nursing
/
v.16
no.1
/
pp.37-47
/
2007
Purpose: To find out the relationship between the shift work, and disrupted sleep and consequent fatigue symptoms. Methods: The questionnaires were given to 345 nurses of 4 hospitals with over 400 beds in Daejeon. Results: The shift workers showed worse subjective quality of sleep than the daytime workers, and had significantly higher frequency of "cannot get to sleep within 30 minutes", "wake up in the middle of the night" and "wake up in the early morning". The shift workers had significantly higher scores of subjective symptoms of fatigue than the daytime workers, and the fatigue was found to be the mental type. The subjective symptoms of fatigue scores were significantly higher in the group who had "cannot get to sleep within 30 minutes", "wake up in the middle of the night" and "wake up in the early morning". Conclusion: The study results indicated that the shift workers had the higher level of subjective symptoms of physical fatigue as well as the worse quality of sleep than the daytime workers. It is speculated that the factors attributable to the poor quality of sleep or sleep induction disorders of nurses of hospitals could be due in major part to adaptational difficulties resulting from frequent night shifts.
To determine the optimal rotational shift system, the effect of the direction of the rotational work shifting on the nocturnal rhythm of plasma melatonin were investigated in nursing students. Two groups of nine volunteers participated as experimental subjects, and two nursing students participated as a control group. The directions of the rotational work shift were as follows: CW(clockwise)-shift were rotated in the direction of day shift(3 days), evening shift(3 days), off duty(1 day) and night shift(5 days), and CCW(conuterclockwise)-shift were done in the reverse direction. Plasma melatonin concentrations was measured by radioimmunoassay. The results were as follows : The plasma melatonin levels were kept low at night and in the following morning in the CW night shift workers, whereas the level started to increase at 05 : 00 hr in two workers of four CCW shift workers. These result suggests that the shift rotation in the CW direction is more acceptable in terms of the adaptation of hormonal rhythms. These results indicate that the CCW rotation of shift work is somewhat better than CCW rotation for the adaptation to shift work on hormonal aspects in nurses.
Objectives: Through comparing sleep variables and autonomic activities among three shifts in shift workers, the authors intended to clarify which shift is most tolerable and to identify the characteristics of their psychological and physical problems. This study is also expected to help shift workers to adapt themselves to their work more effectively. Methods: Fifty one shift workers took part in this study. They were working in a rapidly rotating system in which they worked for 3 days in one shift with one day off between each shift. Based on a sleep diary, sleep latency (SL), sleep period time (SPT), and number of wake after sleep onset (NWASO) were estimated and compared among the three shifts. In assessing sleepiness, Epworth sleepiness scale (ESS) and visual analogue scale (VAS) were used. To evaluate mood states among the three shifts, profile of mood states (POMS) was administered. Heart rate variability (HRV), and the level of adrenaline and noradrenaline were measured to assess autonomic activities. HRV included low frequency power (LF), high frequency power (HF), and LF/HF. Results: SPT was significantly lengthened during the evening shift and SL was shortened during the night shift. The workers showed a drop in alertness at wake-up during morning shift and a drop in alertness at work during night shift. During night shift the subjects complained of physical fatigue and cognitive decline. Comparison of HRV showed that parasympathetic activity was most prominent during the evening shift. Secretion of adrenaline and noradrenaline decreased during the evening shift, though statistically not significant. Conclusion: We found that the evening shift was most tolerable among the three shifts. It is recommended that morning light exposure be done during the morning shift and nocturnal light exposure during the night shift.
Purpose: The purpose of this study was to identify sleep patterns, alertness, and fatigue of shift nurses according to circadian types. Methods: The researchers' enrolled 17 nurses doing shift work in a tertiary hospital. To evaluate circadian types, a morningness-eveningness questionnaire (MEQ) was administered. Sleep patterns were examined using an actigraph for 14 days. To assess alertness and fatigue, Visual Analogue Scale (VAS) was used. The data were analyzed using ANOVA and Kruskal-Wallis test with a SPSS 21.0 program. Results: The researchers found that 17.6% of participants reported morning type, 47.1% neither type, and 35.3% evening type. Mean total sleep time (TST) was 6.8 h, mean sleep efficacy was 82%, level of alertness was 6.54, and level of fatigue was 5.49, regardless of the type of shift work. Evening type nurses had higher variation in TST and alertness, according to the shift patterns than other circadian type nurses. Evening type nurses also had higher fatigue levels than other circadian type nurses. Conclusion: Sleep, alertness, and fatigue were related with circadian types. These results suggest that circadian rhythm management in shift work nurses, particularly in evening type nurses is urgently needed to improve sleep patterns, alertness, and to decrease the level of fatigue.
Journal of the Korean Society for Aviation and Aeronautics
/
v.24
no.3
/
pp.1-9
/
2016
The study examined the effects of shift pattern and expertise on perceived workload and performance for aviation security screeners. 18 security screeners participated in this study, in which data were analyzed by dividing them into two groups (experts vs. less-experts). We measured their perceived workloads and performances (i.e., reading time through X-ray) as a function of shift pattern and time condition. As a result, highly experienced screeners (experts) showed high workload during the morning shift, while lowly experienced screeners (less-experts) reported high workload during the full-day and the afternoon shifts. In addition, less-experts took a longer time to inspect the baggage when they worked for the full-day and the afternoon shifts. Particularly, in the last time slot of the full-dat shift, expert screeners had a high workload, while both groups showed a high-level of workload at around 17:30 in the afternoon shift.
Park, Moon-Seo;Yang, Yun-Jung;Hong, Yeon-Pyo;Kim, Sang-Yon;Lee, Yong-Pil
Journal of Preventive Medicine and Public Health
/
v.43
no.4
/
pp.301-308
/
2010
Objectives: In most DEHP exposure assessment studies, single spot urine sample was used. It could not compare the exposure level among studies. Therefore, we are going to represent the necessity of selection of proper sampling time of spot urine for assessing the environmental DEHP exposure, and the association urinary DEHP metabolites with steroid hormones. Methods: We collected urine and plasma from 25 men. The urine sampling times were at the end of the shift (post-shift) and the next morning before the beginning of the shift (pre-shift). Three metabolites of DEHP {mono(2-ethylhexyl) phthalate [MEHP], mono-(2-ethyl-5-hydroxyhexyl)phthalate [MEHHP], and mono(2-ethyl-5-oxohexyl)phthalate [MEOHP]} in urine were analyzed by HPLC/MS/MS. Plasma luteinzing hormone, follicle stimulating hormone, testosterone, and $17{\beta}$- estradiol were measured at pre-shift using a ELISA kit. A log-transformed creatinine-adjusted urinary MEHP, MEHHP, and MEOHP concentration were compared between the post- and pre-shift. The Pearson’s correlation was calculated to assess the relationships between log-transformed urinary MEHP concentrations in pre-shift urine and hormone levels. Results: The three urinary metabolite concentrations at post-shift were significantly higher than the concentrations in the pre-shift (p<0.0001). The plasma hormones were not significantly correlated with log-transformed creatinine - adjusted DEHP metabolites. Conclusions: To assess the environmental DEHP exposure, it is necessary to select the urine sampling time according to the study object. There were no correlation between the concentration of urinary DEHP metabolites and serum hormone levels.
This study was done to investigate the effects of rapidly-rotating shift work of two-day interval on fatigue level and the concentration of urinary 17-KS, $Na^+,\;Cl^-$. The subjects were 20 nursing college students(control group) and 15 nurses in a university hospital and the study was done from Apr. 21 to May 4th, 1999. In the test group, each 5 nurses were allocated to day shift(8 AM-4 PM), evening shift(4 PM-12 MN) and night shift(12 MN-8 AM) respectively. The fatigue level were measured 30 minutes after work start on the 2nd day of work shift. Urine specimens were collected at 8 AM, 4 PM and 12 MN on the 2nd day of work shift in the control group and 30 minutes before and after work on the 2nd day of work shift in the test group. The data were analyzed with SPSS(for Window, ver 7.5). Statistical analysis was performed by using t-test, paired t-test and ANOVA. The results were as follows. 1. The perceived fatigue level in shift work 1) The physical and mental fatigue level were significantly higher in night shift than that in day or evening shift(p<0.05). In the neuro-sensory fatigue level, night shift showed higher tendency than that in day or evening shift, but there were no significant differences between each shifts. 2) Comparison between the control group and the test group: Physical fatigue level was significantly higher in night shift than that in day or evening shift of the control group(P<.001). Mental fatigue level was significantly higher in day or night shift than that in evening shift of the control group(P<.05). In the neuro-sensory fatigue level, test group showed higher tendency than that in the control group, but there were no significant differences between two groups. 3) The total fatigue level was higher in night shift than that in day shift or evening shift(P<.05). In comparing with the control group, night shift and day shift showed higher total fatigue level than that in the control group(p<0.05). 2. The concentration of urinary 17-KS, $Na^+$ and $Cl^-$ In the control group, urinary 17-KS, $Na^+$ and $Cl^-$ showed higher level in afternoon that in morning and night. In the test group, cr in day and evening shift and $Na^+$ in evening shift showed higher level at the end of work. The 17-KS concentration at the begining and the end of work in three shift groups were lower than those in control group(p<0.05), however, $Cl^-$ concentration at the begining of work in day shift, and the end of work in day and evening shift were higher than those in control group(p<0.05). $Cl^-$ concentration at the begining and end of work in night shift were considerably higher than those in control group repectively(p<0.1, p<001). $Na^+$ concentration showed a higher tendency in three shift groups except at the begining of work in night shift, but there were no statistical difference. In comparing concentration of the 17-KS, $Na^+$ and $Cl^-$ among the shift groups, 17-KS concentration showed a lower tendency and $Na^+,\;Cl^-$ showed a higher tendency in night shift: The result of this study showes that biorhythm of shift work nurse was irregular. Fatigue level as the subjective index for evaluating the health problem concerning shift work was higher in night shift and proved to be in accordance with the concentration of urinary 17-KS, $Na^+$ and $Cl^-$ used as objective indices. Disturbation of biorhythm and work stress due to night shift seems to cause the health problem of nurses and decrease of work efficiency. It is considered that work regualtion is necessary for the rational management of the nursing administration.
This paper describes the optimization of maintenance workforce scheduling at Afam power station in Nigeria. The objective is to determine the optimum schedule to satisfy growing maintenance labour requirements with minimum cost and highest efficiency. Three alternative maintenance workforce schedules are compared. The first alternative is to continue with the traditional five-day workweek schedule currently being practiced by Afam power station maintenance line. The second alternative is to switch to a seven-day workweek schedule for the morning shift only. The third alternative is to use a seven-day workweek schedule for all three work shifts. The third alternative is chosen, as it is expected to save 11% of the maintenance labour cost.
Today freeway is experiencing a severe congestion with incoming or outgoing traffic through freeway ramps during the peak periods. Thus, the purpose of this study is to identify the traffic characteristics, analyze the relationships between the traffic characteristics and finally construct the delay predictive models on the rap junctions of freeway with 70mph speed limit. From the traffic analyses, and model construction and verification for delay prediction on the ramp junctions of freeway, the following results were obtained : ⅰ) Traffic flow showed a big difference depending on the time periods. Especially, more traffic flows were concentrated on the freeway junctions in the morning peak period. ⅱ) The occupancy also showed a big difference depending on the time periods, and the downstream occupancy(Od) was especially shown to have a higher explanatory power for the delay predictive model construction on the ramp junctions of freeway. ⅲ) The delay-occupancy curve showed a remarkable shift based on the occupancies observed : O$\_$d/〈9% and O$\_$d/$\geq$9%. Especially, volume and occupancy were shown to be highly explanatory for delay prediction on the ramp junctions of freeway under O$\_$d/$\geq$9%, but lowly for delay prediction on the ramp junctions of freeway under O$\_$d/〈9%. Rather, the driver characteristics or transportation conditions around the freeway were thought to be a little higher explanatory for the delay prediction under O$\_$d/〈9%. ⅳ) Integrated delay predictive models showed a higher explanatory power in the morning peak period, but a lower explanatory power in the non-peak periods.
본 웹사이트에 게시된 이메일 주소가 전자우편 수집 프로그램이나
그 밖의 기술적 장치를 이용하여 무단으로 수집되는 것을 거부하며,
이를 위반시 정보통신망법에 의해 형사 처벌됨을 유념하시기 바랍니다.
[게시일 2004년 10월 1일]
이용약관
제 1 장 총칙
제 1 조 (목적)
이 이용약관은 KoreaScience 홈페이지(이하 “당 사이트”)에서 제공하는 인터넷 서비스(이하 '서비스')의 가입조건 및 이용에 관한 제반 사항과 기타 필요한 사항을 구체적으로 규정함을 목적으로 합니다.
제 2 조 (용어의 정의)
① "이용자"라 함은 당 사이트에 접속하여 이 약관에 따라 당 사이트가 제공하는 서비스를 받는 회원 및 비회원을
말합니다.
② "회원"이라 함은 서비스를 이용하기 위하여 당 사이트에 개인정보를 제공하여 아이디(ID)와 비밀번호를 부여
받은 자를 말합니다.
③ "회원 아이디(ID)"라 함은 회원의 식별 및 서비스 이용을 위하여 자신이 선정한 문자 및 숫자의 조합을
말합니다.
④ "비밀번호(패스워드)"라 함은 회원이 자신의 비밀보호를 위하여 선정한 문자 및 숫자의 조합을 말합니다.
제 3 조 (이용약관의 효력 및 변경)
① 이 약관은 당 사이트에 게시하거나 기타의 방법으로 회원에게 공지함으로써 효력이 발생합니다.
② 당 사이트는 이 약관을 개정할 경우에 적용일자 및 개정사유를 명시하여 현행 약관과 함께 당 사이트의
초기화면에 그 적용일자 7일 이전부터 적용일자 전일까지 공지합니다. 다만, 회원에게 불리하게 약관내용을
변경하는 경우에는 최소한 30일 이상의 사전 유예기간을 두고 공지합니다. 이 경우 당 사이트는 개정 전
내용과 개정 후 내용을 명확하게 비교하여 이용자가 알기 쉽도록 표시합니다.
제 4 조(약관 외 준칙)
① 이 약관은 당 사이트가 제공하는 서비스에 관한 이용안내와 함께 적용됩니다.
② 이 약관에 명시되지 아니한 사항은 관계법령의 규정이 적용됩니다.
제 2 장 이용계약의 체결
제 5 조 (이용계약의 성립 등)
① 이용계약은 이용고객이 당 사이트가 정한 약관에 「동의합니다」를 선택하고, 당 사이트가 정한
온라인신청양식을 작성하여 서비스 이용을 신청한 후, 당 사이트가 이를 승낙함으로써 성립합니다.
② 제1항의 승낙은 당 사이트가 제공하는 과학기술정보검색, 맞춤정보, 서지정보 등 다른 서비스의 이용승낙을
포함합니다.
제 6 조 (회원가입)
서비스를 이용하고자 하는 고객은 당 사이트에서 정한 회원가입양식에 개인정보를 기재하여 가입을 하여야 합니다.
제 7 조 (개인정보의 보호 및 사용)
당 사이트는 관계법령이 정하는 바에 따라 회원 등록정보를 포함한 회원의 개인정보를 보호하기 위해 노력합니다. 회원 개인정보의 보호 및 사용에 대해서는 관련법령 및 당 사이트의 개인정보 보호정책이 적용됩니다.
제 8 조 (이용 신청의 승낙과 제한)
① 당 사이트는 제6조의 규정에 의한 이용신청고객에 대하여 서비스 이용을 승낙합니다.
② 당 사이트는 아래사항에 해당하는 경우에 대해서 승낙하지 아니 합니다.
- 이용계약 신청서의 내용을 허위로 기재한 경우
- 기타 규정한 제반사항을 위반하며 신청하는 경우
제 9 조 (회원 ID 부여 및 변경 등)
① 당 사이트는 이용고객에 대하여 약관에 정하는 바에 따라 자신이 선정한 회원 ID를 부여합니다.
② 회원 ID는 원칙적으로 변경이 불가하며 부득이한 사유로 인하여 변경 하고자 하는 경우에는 해당 ID를
해지하고 재가입해야 합니다.
③ 기타 회원 개인정보 관리 및 변경 등에 관한 사항은 서비스별 안내에 정하는 바에 의합니다.
제 3 장 계약 당사자의 의무
제 10 조 (KISTI의 의무)
① 당 사이트는 이용고객이 희망한 서비스 제공 개시일에 특별한 사정이 없는 한 서비스를 이용할 수 있도록
하여야 합니다.
② 당 사이트는 개인정보 보호를 위해 보안시스템을 구축하며 개인정보 보호정책을 공시하고 준수합니다.
③ 당 사이트는 회원으로부터 제기되는 의견이나 불만이 정당하다고 객관적으로 인정될 경우에는 적절한 절차를
거쳐 즉시 처리하여야 합니다. 다만, 즉시 처리가 곤란한 경우는 회원에게 그 사유와 처리일정을 통보하여야
합니다.
제 11 조 (회원의 의무)
① 이용자는 회원가입 신청 또는 회원정보 변경 시 실명으로 모든 사항을 사실에 근거하여 작성하여야 하며,
허위 또는 타인의 정보를 등록할 경우 일체의 권리를 주장할 수 없습니다.
② 당 사이트가 관계법령 및 개인정보 보호정책에 의거하여 그 책임을 지는 경우를 제외하고 회원에게 부여된
ID의 비밀번호 관리소홀, 부정사용에 의하여 발생하는 모든 결과에 대한 책임은 회원에게 있습니다.
③ 회원은 당 사이트 및 제 3자의 지적 재산권을 침해해서는 안 됩니다.
제 4 장 서비스의 이용
제 12 조 (서비스 이용 시간)
① 서비스 이용은 당 사이트의 업무상 또는 기술상 특별한 지장이 없는 한 연중무휴, 1일 24시간 운영을
원칙으로 합니다. 단, 당 사이트는 시스템 정기점검, 증설 및 교체를 위해 당 사이트가 정한 날이나 시간에
서비스를 일시 중단할 수 있으며, 예정되어 있는 작업으로 인한 서비스 일시중단은 당 사이트 홈페이지를
통해 사전에 공지합니다.
② 당 사이트는 서비스를 특정범위로 분할하여 각 범위별로 이용가능시간을 별도로 지정할 수 있습니다. 다만
이 경우 그 내용을 공지합니다.
제 13 조 (홈페이지 저작권)
① NDSL에서 제공하는 모든 저작물의 저작권은 원저작자에게 있으며, KISTI는 복제/배포/전송권을 확보하고
있습니다.
② NDSL에서 제공하는 콘텐츠를 상업적 및 기타 영리목적으로 복제/배포/전송할 경우 사전에 KISTI의 허락을
받아야 합니다.
③ NDSL에서 제공하는 콘텐츠를 보도, 비평, 교육, 연구 등을 위하여 정당한 범위 안에서 공정한 관행에
합치되게 인용할 수 있습니다.
④ NDSL에서 제공하는 콘텐츠를 무단 복제, 전송, 배포 기타 저작권법에 위반되는 방법으로 이용할 경우
저작권법 제136조에 따라 5년 이하의 징역 또는 5천만 원 이하의 벌금에 처해질 수 있습니다.
제 14 조 (유료서비스)
① 당 사이트 및 협력기관이 정한 유료서비스(원문복사 등)는 별도로 정해진 바에 따르며, 변경사항은 시행 전에
당 사이트 홈페이지를 통하여 회원에게 공지합니다.
② 유료서비스를 이용하려는 회원은 정해진 요금체계에 따라 요금을 납부해야 합니다.
제 5 장 계약 해지 및 이용 제한
제 15 조 (계약 해지)
회원이 이용계약을 해지하고자 하는 때에는 [가입해지] 메뉴를 이용해 직접 해지해야 합니다.
제 16 조 (서비스 이용제한)
① 당 사이트는 회원이 서비스 이용내용에 있어서 본 약관 제 11조 내용을 위반하거나, 다음 각 호에 해당하는
경우 서비스 이용을 제한할 수 있습니다.
- 2년 이상 서비스를 이용한 적이 없는 경우
- 기타 정상적인 서비스 운영에 방해가 될 경우
② 상기 이용제한 규정에 따라 서비스를 이용하는 회원에게 서비스 이용에 대하여 별도 공지 없이 서비스 이용의
일시정지, 이용계약 해지 할 수 있습니다.
제 17 조 (전자우편주소 수집 금지)
회원은 전자우편주소 추출기 등을 이용하여 전자우편주소를 수집 또는 제3자에게 제공할 수 없습니다.
제 6 장 손해배상 및 기타사항
제 18 조 (손해배상)
당 사이트는 무료로 제공되는 서비스와 관련하여 회원에게 어떠한 손해가 발생하더라도 당 사이트가 고의 또는 과실로 인한 손해발생을 제외하고는 이에 대하여 책임을 부담하지 아니합니다.
제 19 조 (관할 법원)
서비스 이용으로 발생한 분쟁에 대해 소송이 제기되는 경우 민사 소송법상의 관할 법원에 제기합니다.
[부 칙]
1. (시행일) 이 약관은 2016년 9월 5일부터 적용되며, 종전 약관은 본 약관으로 대체되며, 개정된 약관의 적용일 이전 가입자도 개정된 약관의 적용을 받습니다.