• Journal of Nutrition and Health
• /
• 제34권6호
• /
• pp.645-655
• /
• 2001

The purpose of this study is to investigate the dietary intake and bone mineral density(BMDs) in college women(n = 10), female swimmers(n = 10), and female weight lifters(n = 10). BMDs of lumbar spine(L2-L4), femoral neck, ward's triangle, and trochanter were measured with dual-energy X-ray absorptiometry. The results are summarized as follows. In swimmers and weight lifters, mean daily intakes of energy, protein, and fat were higher than those of college women and the intake of carbohydrate was significantly high in weight lifters. Also in swimmers and weight litters, mean daily intakes of animal flood, phosphorus, vitamin A, vitamin B$_1$, vitamin B$_2$, niacin, vitamin C, and cholesterol were found higher than those of college women but there was difference among the types of exercise. According to correlation analysis between nutrient intake and BMDs, intakes of energy, protein, carbohydrate, and vitamin B$_1$ were positively associated with BMDs of lumbar spines. According to stepwise multiple recession analysis, BMDs of lumbar spines were affected by intakes of protein, Fe, phosphorus, and vitamin B$_2$, also BMDs of femur were affected by each of vegetable protein, dietary fiber, and fe. from the above explanation, the nutrient intakes can be independent factor besides exercise. In conclusion, the weight lifting, resistant exercise, resulted in increase of both BMDs of lumbar spines and femur specially in growing and adult period of female. Whereas swimming lead to increase of BMDs of lumbar spine and decrease of BMDs of femur in female.

• 항공우주기술
• /
• 제12권2호
• /
• pp.99-107
• /
• 2013

화성은 국지적인 강한 바람과 그 바람에 의해 표면의 먼지들이 솟아오르는 현상들을 가지고 있다. 대기 순환과 먼지 상승은 서로 관계가 있다고는 알려져 있지만, 먼지 상승의 역학적 원인은 명확하게 밝혀진 것은 없다. 먼지 폭풍은 히말라야 산 높이까지 상승하는 매우 강한 상승 기류인데 이런 기류들은 탐사선이 착륙할 때 또는 로버가 탐사를 수행할 때 피해야 할 위험 요소이다. 본 연구에서는 대기 순환과 관련된 먼저 폭풍의 발생 시기와 발생 지역 분포에 대해 조사하였다. 대기 순환의 원천적인 에너지는 태양이기 때문에 먼지 폭풍의 발생 시기와 화성의 계절에 대해 분석하였고, 최종적으로는 발생 시기와 발생 지역의 공간 분포의 관계를 지도로 작성하였다. 이 자료를 토대로 화성 먼지 폭풍의 발생이 빈번하지 않은 지역과 시기를 예측할 수 있다. 향후 이 자료는 국내 자력으로 화성 착륙선을 보낼 때 착륙시기와 관계하여 발사시점 및 착륙지점을 선정하는데 있어서 결정적인 역할을 할 것이라고 기대한다.

• International Journal of Naval Architecture and Ocean Engineering
• /
• 제9권5호
• /
• pp.552-567
• /
• 2017

The floating crane vessel in waves gives rise to the motion of the lifted object which is connected to the hoisting wire. The dynamic tension induced by the lifted object also affects the motion responses of the floating crane vessel in return. In this study, coupled motion responses of a floating crane vessel and a lifted subsea manifold during deep-water installation operations were investigated by both experiments and numerical calculations. A series of model tests for the deep-water lifting operation were performed at Ocean Engineering Basin of KRISO. For the model test, the vessel with a crane control system and a typical subsea manifold were examined. To validate the experimental results, a frequency-domain motion analysis method is applied. The coupled motion equations of the crane vessel and the lifted object are solved in the frequency domain with an additional linear stiffness matrix due to the hoisting wire. The hydrodynamic coefficients of the lifted object, which is a significant factor to affect the coupled dynamics, are estimated based on the perforation value of the structure and the CFD results. The discussions were made on three main points. First, the motion characteristics of the lifted object as well as the crane vessel were studied by comparing the calculation results. Second, the dynamic tension of the hoisting wire were evaluated under the various wave conditions. Final discussion was made on the effect of passive heave compensator on the motion and tension responses.

• PNF and Movement
• /
• 제4권1호
• /
• pp.9-18
• /
• 2006

Purpose: The purpose of this study was to investigate the effect of Proprioceptive Neuromuscular Facilitation (PNF) applied to the unilateral upper extremity on the muscle activation of contralateral lower extremity. Twenty-two healthy subjects (mean age of 23.7 years) participated in this study. Method : PNF patterns applied on the unilateral upper extremity in all subjects were the flexion/abduction/external rotation and lifting pattern. The hold and appoximation techniques for the irradiation were applied to end range of both patterns. Muscle activations in four patterns were measured in vastus medialis, tibialis anterior, rectus femoris, and gastrocnemius medial muscles of contralateral lower extremity using surface EMG system. Each EMG value in individual muscle was normalized for maximal voluntary contraction. The data were analyzed by one factor analysis of variance with repeated measure test. Result : There were significant differences in the between-subject effect (muscles) and within-subject effect (patterns) in comparison of muscle activation by application of PNF patterns (p<.05). The irradiation led to higher activation in the flexion/abduction/external rotation pattern than that of lifting pattern in all muscles (p<.05). The approximation techniques revealed more activations than these of hold technique in all muscles (p<.05). Conclusion : These results suggest that the application of PNF patterns to the unilateral upper extremity affect on the muscle activation of contralateral lower extremity and increase according to the intensity of resistance. This mechanism of contralateral effect might provide a help to the development of treatment method for the affected side and functional improvement for the patients who have damages of central nervous system or musculoskeletal problems by orthopedic injury.

• 한국건설관리학회논문집
• /
• 제14권5호
• /
• pp.153-163
• /
• 2013

건축물이 고층화, 대형화 될수록 수직 양중 계획 및 운영에 관한 중요성이 부각되고 있다. 이에 프로젝트 초기 단계에 실제 모델과 유사한 건설용 리프트 양중계획을 수립하려는 노력이 계속되고 있지만 프로젝트 착수 후 리프트 운행을 컨트롤 할 수 있는 시스템은 부재한 실정이다. 따라서 본 논문에서는 건설용 리프트 운영 효율증대를 위하여 센서를 사용한 리프트 운행 정보를 수집하고 실시간 분석이 가능한 건설용 리프트 최적화 운행 시스템 개발을 실시 및 검증 단계를 수행하여, 양중 효율의 지표가 되는 사용자 대기 시간의 단축을 도모하고 향후 무인 스마트 리프트의 초석이 되는 시스템을 제시하고자 한다.

• 한국전문물리치료학회지
• /
• 제21권4호
• /
• pp.56-66
• /
• 2014

For maintaining adequate psychometric properties when reducing the number of items from an instrument, item level psychometrics is crucial. Strategies such as low item correlation or factor loadings, using classical test theory, have traditionally been advocated. The purpose of this study is to describe the development of a new short form assessing the impact of low back pain on physical activity. Rasch measurement model has been applied to the International Classification of Functioning, Disability and Health Activity Measure (ICF-AM). One hundred and one individuals with low back pain aged 19-89 years (mean age: $48.1{\pm}17.3$) who live in the community were participated in the study. Twenty-seven items of lifting/carrying construct of the ICF-AM were analyzed. Ten items were selected from the construct to create a short form. Item elimination criteria include: 1) high or low mean square (out of the range: .6-1.4 for the fit statistics), 2) similar item calibrations to adjacent items, 3) person separation value, and item-person map for potential gap in person ability continuum. All 10 items of the short form fit to the Rasch model except one item (i.e., carrying toddler on back). Despite its high infit and outfit statistics (1.90/2.17), the item had to be reinstated due to potential gaps at the upper extreme of person ability level. The short form had a slightly better spread of person ability continuum compared to the entire set of item. The created short form separated individuals with low back pain into nearly 4 groups, while the entire set of items separated the individuals into 6 groups. The findings prompted multidimensional models for better explanation of the lifting/carrying domain. The item level psychometrics based on the Rasch model can be useful in developing short forms with rationally retained items.

• 한국산업정보학회논문지
• /
• 제5권2호
• /
• pp.1-8
• /
• 2000

인력물자취급(MMH)작업은 작업현장에서 육체적 상해와 요통(LBP)을 발생시키는 주요 원인 중에 하나이며 이러한 산업재해는 점점 증가하고 있는 실정이다. 특히 좋지 않은 작업환경 즉, 비탈진 경사면에 위치한 농장이나 과수원, 항만부두의 하역작업, 경사진 벌목장 작업, 광산의 막장에서의 작업은 많은 재해의 위험성을 초래하며, 신체균형의 상실은 근골격계(musculoskeletal System)의 부상을 초래하게 된다. 본 연구는 경사면에서의 들기작업시 작업자의 근육의 force information과 근피로도를 측정하기 위해 EMG 시스템을 이용하였다. 측정결과 AEMG의 경우 모든 조건에서 일반적으로 multifidus 근육에 걸리는 부하가 다른 근육에서보다 많은 것으로 나타났고, 15$^{\circ}$, 20$^{\circ}$인 경우 neck extensors의 사용이 많은 것으로 나타났다. MPF천이 결과 공통적으로 multifidus부위 근육의 천이정도가 가장 많은 것으로 나타났다. 근육별 부하(%)에 대한 결과는 deep spinal 근육인 multifidus, erectorspinae부위가 상대적으로 많은 것으로 나타났고 neck extensor부위는 근육분담이 적은 것으로 나타났다.

• Safety and Health at Work
• /
• 제10권1호
• /
• pp.3-20
• /
• 2019

This review aimed to identify risk factors for occupational accidents and illnesses among young workers in the Nordic countries and to attain knowledge on specific vulnerable groups within the young working force that may need special attention. We conducted a systematic review from 1994 to 2014 using five online databases. Of the 12,528 retrieved articles, 54 met the review criteria and were quality assessed, in which data were extracted focusing on identifying occupational safety, health risk factors, and vulnerable groups among the young workers. The review shows that mechanical factors such as heavy lifting, psychosocial factors such as low control over work pace, and organizational factors such as safety climate are all associated with increased injury risk for young Nordic workers. Results show that exposures to chemical substances were associated with skin reactions, e.g., hand eczema. Heavy lifting and awkward postures were risk factors for low back pain, and high job demands were risk factors for mental health outcomes. The review identified young unskilled workers including school drop-out workers as particularly vulnerable groups when it comes to occupational accidents. In addition, apprentices and young skilled workers were found to be vulnerable to work-related illnesses. It is essential to avoid stereotyping young Nordic workers into one group using only age as a factor, as young workers are a heterogeneous group and their vulnerabilities to occupational safety and health risks are contextual. Politicians, researchers, and practitioners should account for this complexity in the education, training and organization of work, and workplace health and safety culture.

• Journal of Preventive Medicine and Public Health
• /
• 제26권1호
• /
• pp.20-36
• /
• 1993

Work-related low back pain is one of the major factors that cause the loss of working power especially in actively working age, therefore controlling the work-related low back pain is one of the major issues in the field of industrial safety and health. This study was performed for detecting the risk factors and proposing the efficient control program of the work-related low back pain. The subjects were male workers employed at the manufacturing industry in Pusan with longer than 6 months' working duration. The data was collected by self-reported questionnaire and interview from May 1 to October 31,1992. The contents of questionnaire were as follows:. the experience of low back pain within the recent one month, general characteristics(age, marital status, education level, religion, regular exercise), physical characteristics(height, weight), employment status(working duration, daily working hours, rest during work, satis(action fur the job), type of work and working environments(posture, forward bending, lifting and movement, satisfaction for table and chair). The result was analyzed for 608 entire respondents by case-control comparative method. The number of cases was 152 with a history of work-related low back pain, so the relative frequency of self-reported work-related low back pain was 25.0%, and the number of controls was 344 without any history of low back pain. As a result, two characteristics of the employment status(working duration, satisfaction fur the job) and all characteristics of type of work and working environments showed a statistical significance between the case and control groups(p<0.01). The Oddb ratios of these variables for Work-related low back pain were calculated. They were 7.88 for the satisfaction fur chair, 7.86 for lifting and movement,3.31 for satisfaction for table, and 2.22 fur bending forward(p<0.01). And for the multivariate logistic regression analysis confirmed that unsatisfaction for table was independent risk factor for Work-related low back pain. In summary, though this study was based upon the self-reported questionnaire and the subjective complaints, the satisfaction for chair, lifting and movement, satisfaction for table, and bending forward concerned with the type of work and working environments were considered as the main factors causing the work-related low back pain, and the work-related low back pain may be preventable by the ergonomic control of these factors.

• 한국산업보건학회지
• /
• 제24권3호
• /
• pp.383-392
• /
• 2014

Purpose: In this study, we sought to understand the risk factor for chronic disease of workers by studying the association between occupational standing time and metabolic syndrome(MetS) in full-time 300 male workers. Materials: Data on age, life habit, work related information of the subjects were surveyed using self-reported questionnaire and interview. MetS was identified based on the report of Alberti et al.(2009). As for the data analysis, SPSS 19.0 was used to conduct the descriptive statistic, ANOVA, Pearson correlation coefficient and multiple logistic regression analysis. Results: Daily working hour affects on the lifting heavy objects, running and strenuous exercise(r=-0.137, p<0.01), and total physical function decreased with the increase in age(r=-0.145, p<0.01). Also, obese was significantly associated with genuflection and bend over(r=-0.110, p<0.05). On multiple logistic regression analysis for the diagnostic indices of MetS, occupational standing time were significantly associated with waist circumference(odds ratio=0.885, ${\beta}$ value=-0.122, 95% CI=0.797-0.983, p<0.05) and triglyceride (odds ratio=0.873, ${\beta}$ value=-0.136, 95% CI=0.800-0.953, p<0.01). Conclusions: These results suggest that the working posture may be important risk factor in pathogenesis and growing of MetS and cardiovascular disease.