• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.19 no.4
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• pp.412-422
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• 2009

This study was conducted to assess exposure to musculoskeletal disorder(MSD) risk factors in hospital personnel who performed non-routinized work tasks. A tool ("PATH-KOSHA" version) was newly revised from PATH(Posture, Activity, Tools and Handling) method and uploaded into a personal digital assistant(PDA). The version was used, on a basis of direct-observation, to collect PATH data at the 2 hospital settings in different regions. Job analysis was performed to get various information (e.g., work and rest time, task type) as well. The data collected were visually checked for data cleaning and stored for future data analysis. A total of 1,992 PATH observations were made for 37 hospital workers. Exposure levels varied across 18 items of the MSD risk factors. The highest percent time spent on non-neutral postures was 53% for wrist deviation, followed by 47%(pinch grip), 35%(trunk posture), 23%(neck posture), and 20%(shoulder/arm posture). The highest percent time spent among hand activity level(HAL) variables was 55% for HAL-cat2 (HAL: 3.3 - <6.7). The percent time of items with respect to both loads with more than 5kg and contact stress was less than 4%. Vibration was not exposed in the study workers. Different aspects were discussed for findings. The study results showed that wrist deviation was highest in percent time spent on awkward posture while HAL-cat2 was highest in hand repetition. The study suggests that distal upper extremity posture and HAL should be primarily addressed and controlled in non-routinized work including the hospital settings.

• Korean Chemical Engineering Research
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• v.61 no.3
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• pp.378-387
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• 2023

Petrochemical is an energy consuming industry that consumes about 30% of total industrial energy consumption and is a representative carbon dioxide (CO₂) emission source. Among them, the Naphtha Cracking Center (NCC), which produces ethylene, propylene, propane and mixed C4, consumes large amounts of energy and emits significant amounts of CO₂. For this reason, an integrated techno economic- environmental impact assessment aimed at reducing energy consumption and environmental impact factors is necessary to ensure efficiency in terms of economics and environment. This study aims to analyze the efficiency of the heat exchanger network used in the existing NCC base on the pinch analysis and select an improvement plan that can reduced energy consumption. In order to reduces the utility consumption in the process, an optimal heat exchanger network considering the high-temperature and low-temperature stream was derived, and the economic evaluation was conducted by considering the trade-off between the reduction in utility consumption and the increase in heat exchanger installation cost. In addition, an environmental impact assessment was conducted on the reduced CO₂ emission in consideration of the environmental aspect, and the economic environmental impact assessment used the payback period to recover the invested funds to come up with an energy saving plan that can be applied based on the actual process. As a result of considering the economic-environmental impact assessment, when the environmental impact assessment was not considered, it was 4.29 months, 3.21 months, and 3.39 months for each case, and when considering the environmental impact assessment, it was 4.24 months, 3.17 months, and 3.35 months for each case. These results appeared equally both when the environmental impact assessment was not include and when it was include. In addition, a sensitivity analysis was conducted for each case to determine how important factors affect the payback period. As a result of the sensitivity analysis, the cost of the heat exchanger was identified as a major factor influencing the overall cost.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.18 no.2
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• pp.122-132
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• 2008

The purpose of this study is to present the basic materials of a developmental counterplan by assessing prevalence of musculoskeletal symptoms and characteristics of work-related ergonomic risk factors. The prevalence of musculoskeletal symptoms of 64 vineyard workers was investigated by using a self-reported questionnaire. And the vineyard workers' tasks were also collected and analyzed during 9-month period by observing and videotaping methods to identify the ergonomic risk factors. The prevalence rate of musculoskeletal symptoms of female(84.4%) was much higher than that of male(62.5%) and a total prevalence rate was 73.4%. There was no different prevalence of musculoskeletal symptoms between age over 60 years and under 60 years. The prevalence rates of musculoskeletal complaints for each body part were 48.4%, 42.2%, and 35.9% for the wrist, legs/knee, and shoulder, respectively. In postural risk analysis, 7 works(REBA score) represented the high risk tasks such as delivering harvest boxed(12), picking cluster(11) and so on. The main works(exposure score) were orderly ranked as picking cluster(1590), pruning branch(388), and cluster thinning(327). The risk factors of vineyard work were identified as follows: shoulder flexion(${\geq}45^{\circ}$), wrist Flex./Ext.(${\geq}15^{\circ}$), hand force(power/pinch-grip), and prolonged standing(${\geq}4hr$). The engineering solutions including an improvement of hand tools, working process, and working environment should be applied to the high risky tasks in order to resolve the ergonomic problems. The administrative solutions such as improving a distribution of resting time, an exercise cure, an early recognition of symptoms and rehabilitation might be another solution for reducing musculoskeletal symptoms in vineyard workers.

• Journal of the Ergonomics Society of Korea
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• v.28 no.4
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• pp.9-15
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• 2009

Our study goal is to find out how the table height influences functional ability of upper extremity to patients with stroke when they are having therapy. In this study, we tested forty patients with stroke at the age of over sixty-five who do not have visual, auditory disability and have no difficulty in communicating and moving things by using upper extremity. And they were able to pinch grip in hospital. We used occupational table for occupational therapy as Lab Materials. We also used cube and pegs board to test upper extremity functional ability. We used occupational table for occupational therapy as Lab Materials and we used cube and pegs board to test upper extremity functional ability. The method is that we measured the recommended table height that takes the subjects' size into consideration and patients' preferred table height and therapists' preferred table height and we applied them and then we have done a comparative analysis and set significance level(p<0.05). As the result, we found the Statistically significant between the recommended height and the other two, which are patients' preferred height and therapists' preferred height. We also discovered that functional ability of upper extremity varies significantly depending on each table height. We came to a conclusion that the table height had effects on the upper extremity functional ability of patients with stroke who are over sixty-five years old. It is therefore considered that the proper table height is important to improve upper extremity functional ability of patients with stroke for their physical therapy.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.33 no.4
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• pp.281-285
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• 2020

Oxide semiconductor devices have become increasingly important because of their high mobility and good uniformity. The channel length of oxide semiconductor thin film transistors (TFTs) also shrinks as the display resolution increases. It is well known that reducing the channel length of a TFT is detrimental to the current saturation because of drain-induced barrier lowering, as well as the movement of the pinch-off point. In an organic light-emitting diode (OLED), the lack of current saturation in the driving TFT creates a major problem in the control of OLED current. To obtain improved current saturation in short channels, we fabricated indium gallium zinc oxide (IGZO) TFTs with single gate and double gate structures, and evaluated the electrical characteristics of both devices. For the double gate structure, we connected the bottom gate electrode to the source electrode, so that the electric potential of the bottom gate was fixed to that of the source. We denote the double gate structure with the bottom gate fixed at the source potential as the BGFP (bottom gate with fixed potential) structure. For the BGFP TFT, the current saturation, as determined by the output characteristics, is better than that of the conventional single gate TFT. This is because the change in the source side potential barrier by the drain field has been suppressed.

• PNF and Movement
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• v.20 no.2
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• pp.147-156
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• 2022

Objective: Electrical stimulation is an assistive technology used to aid the recovery of upper limb use after stroke. The purpose of this systematic review was to determine the effects of electrical stimulation on upper extremity function in individuals with hemiparetic stroke and to develop an evidence base that supports the use of electrical stimulation for upper limb recovery after stroke. Design: A systematic review based on randomized controlled trials (RCTs). Methods: Studies published before April 20 2021 were collected for this review by searching PubMed, four other databases, and RCTs that reported the effects of electrical stimulation on upper extremity function in individuals with the characteristic stroke type. Information on the following parameters was extracted from each study: surname of first author, published year, country, participants, intervention, intervention's intensity, comparison, outcomes, additional therapy, and summary of results. This review also evaluated the bias within each study, including any selection bias, performance bias, detection bias, attrition bias, and reporting bias. Results: This review included five RCTs, and 208 stroke patients were included in the analysis. Stroke patients who underwent electrical stimulation showed significantly improved grip and pinch strengths, wrist range of motion, and basic daily living compared to those in the control group; however, there was no improvement in upper extremity function. Of the selected papers, 60% showed a "high risk" of performance bias, and 20% showed a "high risk" of detection bias. Conclusions: The results of this systematic review suggest that electrical stimulation provides some benefits to stroke patients, such as improved hand strength and range of motion. However, future studies are needed to provide clinical evidence of the effects of electrical stimulation on upper extremity function in stroke patients.

• Steel and Composite Structures
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• v.49 no.6
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• pp.615-631
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• 2023

To investigate the seismic behavior of steel slag self-stressing concrete-filled circular steel tubular (SSSCFCST) columns, 14 specimens were designed, namely, 10 SSSCFCST columns and four ordinary steel slag (SS) concrete (SSC)-filled circular steel tubular (SSCFCST) columns. Comparative tests were conducted under low reversed cyclic loading considering various parameters, such as the axial compression ratio, diameter-thickness ratio, shear-span ratio, and expansion ratio of SSC. The failure process of the specimens was observed, and hysteretic and skeleton curves were obtained. Next, the influence of these parameters on the hysteretic behavior of the SSSCFCST columns was analyzed. The self stress of SS considerably increased the bearing capacity and ductility of the specimens. Results indicated that specimens with a shear-span ratio of 1.83 exhibited compression bending failure, whereas those with shear-span ratios of 0.91 or 1.37 exhibited drum-shaped cracking failure. However, shear-bond failure occurred in the nonloading direction. The stiffness of the falling section of the specimens decreased with increasing shear-span ratio. The hysteretic curves exhibited a weak pinch phenomenon, and their shapes evolved from a full shuttle shape to a bow shape during loading. The skeleton curves of the specimens were nearly complete, progressing through elastic, elastoplastic, and plastic stages. Based on the experimental study and considering the effects of the SSC expansion rate, shear-span ratio, diameter-thickness ratio, and axial compression ratio on the seismic behavior, a peak displacement coefficient of 0.91 was introduced through regression analysis. A simplified method for calculating load-displacement skeleton curves was proposed and loading and unloading rules for SSSCFCST columns were provided. The load-displacement restorative force model of the specimens was established. These findings can serve as a guide for further research and practical application of SSSCFCST columns.

• Journal of Nutrition and Health
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• v.10 no.1
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• pp.49-58
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• 1977

Nutrition counselors in Korea often encounter difficulty in their attempt to change village women's attitudes regarding food taboos which are counter to good eating habits. There are a great many food superstitions which are not due to religious influence, but seem to be related to shape and composition of food. Many expectant mothers superstitiously avoid eating certain foods for fear that they may cause mental or physical abnormality in their babies. As was shown in a previous survey (Mo, 1966)of villages in all provinces except Jeju Island, such superstitions were common among pregnant and lactating mothers. Many food taboos and superstitions based on non-scientific and irrational ideas do exist even in modern society, and are a major obstacle to nutritionally adequate food consumption. A study of food taboos among women of Jeju Island was undertaken from November to December of 1976, these results to be compared as well with those of the previous study. There were 73 items found to be prohibited during pregnancy. Of these, 48.7% were of the deaf group, 17.4% fish, 5.5% eggs, 4.7% cereal, and only 2.2% fruit. Of 252% women respondents, 111 (45% ) abstained from eating chicken, duck, and shark because of the belief that they would cause their babies to be born with gooseflesh or shark skin. Many of them avoided rabbit meat for fear that their babies might be born with harelip. It was also feared that a baby would become disfigured if his mother ate duck, goat, dog meat, chicken or duck eggs, or soup made of bones. A common superstition was that highly spiced or salty foods would cause the fetus to be hairless. Squid and octopus were believed to cause babies to have weak bones, or none at all. Most of these food taboos were associated with fears concerning Physical structure and appearance of unborn babies. Other taboos were associated with fear of undesirable behavioral characteristics. For example, some mothers thought that a baby would pinch or bite the mother's breast during the weaning period, if crab meat were eaten during pregnancy. Unevenly sliced rice cake, loach, snake meat and eel were also believed to cause a baby to be ill-tempered. The findings of this study are remarkably similar to those of the previous study conducted by the authour in 1966. Most of the same food taboos, based on non-scientific and irrational reasons, were found on Jeju Island as on the peninsula, and thor were similarly wide-spread. The results of correlational analysis show that the most significant factors related to prevalence of food taboos, are level of education and religious background. Number of food taboos is correlated with level of education. Also, food taboos are least freqent among the Christian woman. Proper nutrition education should he undertaken in order to encourage intake of protein-rich food, particularly during pregnancy when nutritional needs of mother and fetus are great.

• Economic and Environmental Geology
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• v.9 no.1
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• pp.1-11
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• 1976

It is believed that geological survey, drilling and geophysical survey which was carried out on Tertiary deposits in Pohang is a valuable but through the studying of many Tertiary sediments in Japan discovered many questions on analysis of final report prepared by National geological survey. The main reason is: 1. The seismic sound velocity which have regulated in the final report prepared by geological survey for Tertiary deposits in Pohang was 1,500-2,000m/sec in spite of oil bearing sediments of same age in Japan are 2,000-3,800m/sec. These may means the requirement of reconsideration of seismic velocity for Tertiary deposits in Pohang and required to have a dipper drilling. 2. Stratigraphically, geophysically, and paleontologically, the Tertiary deposits in Pahang land area is similar with that of Nishiyama-Hunakawa formations of Akita oil field in Japan. Nishiyama-Hunakawa formation is the main oil bearing formation in Japan. 3. Those valcanic rock including andestitic rock and liparitic rock which have extensively distributed over either at land area or at sea bottom, assumed by geological survey as the base of Tertiary sediments. But in case of Japan many oil bearing deposits are in over laid by these kind of volcanic rock. Therefore a possible of same condition with Japan is presumable on Tertiary sediments in Pohang. 4. It is believed that the Tertiary sediments of land area in Pohang is the extension of offshore basin but is wandering that the final report submitted by geologic survey have not remain any word on report of ECAFE discribed so much problematics as followed: A. Although it was assumed that no great thickness exceeding 1,000 meters, or major structures would be encountered in the Tertiary offshore sequence, it was hoped that shallow hydrocarbon deposits might be found, because these sediment are lithologically similar to those of the same age in the producing area of the northwest Honshu region of Japan where hydrocarbon are extracted from depths of only 500 to 600 meters. B. Four possible hydrocarbon trap conditions are represented in the survey area: anticlinal folds, faults, pinch outs, along the igneous basement and lateral facies changes. C. Most of the prime possible reservoir area are beyond the 50 meter water depth mark, except for the structures in Yonil Bay. D. Despite the shallowness of the offshore basin, sufficient trap condition exist in the area to warrant further exploration for hydrocarbon. 5. All of the problems mentioned above have gave us a strong reasons to have us hesitating to make a final conclusion on Tertiary problems in Pohang, before to have a drill to a depth to 3,000 meters or more whatever it is the Tertiary or a Mesozoics below 1,000 meters.

• The Korean Journal of Rehabilitation Nursing
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• v.6 no.1
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• pp.79-89
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• 2003

Purpose: This research with one group pre-post design was carried out to test the practical feasibility to administrate the Music Movement program developed for the stroke patients. Subjects: 12 stroke survivors at "J" Public Health Center in Seoul. were participated in. The average age was 68 years old, the ratio of sex was almost 5.8:4.2, the duration of was almost over 1 year. Method: Music Movement program was conducted for 2 hours ${\times}$ 1day ${\times}$ 6 weeks. The contents of Music Movement program were consisted of the preparatory activities, main activities and the wrap up activities. The preparatory activities are ice braking, greeting, explanation of the aims of music movement program, and introduction of stroke disease and ROM exercise. The main activities are the body motions with singing and playing musical instruments. The wrap up activities are stretching and joints and discussion of home activities. Data Collection: The outcome variables are muscle strength, finger pinch power, ROMs, flexibility, depression, and life satisfaction. Depression was measured by CES-D(Kim, I. J., 1999), life satisfaction by ladder scale(McDowell & Newell, 1996), and ADL state(Holbrook & Skilbeck, 1983). Data Analysis: SPSS/PC 10.0 for Window was used. Wilcoxon Signed Ranks Test was used to analyze outcome measures. The level of statistical significance was set at p<.05. Results: This program was effective to decrease the depression level of subjects(p<.05). The muscle strength, hand grip power, ROMs, life satisfaction, and rehabilitation state of the subjects were slightly increased but no significant differences were found between the pre and post test. Additionally every patient replied that they were very satisfied and expressed their appreciation for this program very much. Of course they strongly want to continue to participate in and meet the peer group again. Conclusion: Considering these results, the practical feasibility of Music Movement program can be supported. Therefore, this Music Movement program can be examined with the quasi-experimental design with control group and ongoing reviews. After that, this program would be applied in public health centers, medical institutes, and welfare centers for the rehabilitation of stroke patients.