• Environmental Engineering Research
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• v.19 no.4
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• pp.345-354
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• 2014

In this paper, effects of physical configurations and operating conditions on bubble column performance were analyzed in terms of bubble hydrodynamic and mass transfer parameters. Bubble column with 3 different dimensions and 7 gas diffusers (single / multiple orifice and rigid / flexible orifice) were applied. High speed camera and image analysis program were used for analyzing the bubble hydrodynamic parameters. The local liquid-side mass transfer coefficient ($k_L$) was estimated from the volumetric mass transfer coefficient ($k_La$) and the interfacial area (a), which was deduced from the bubble diameter ($D_B$) and the terminal bubble rising velocity ($U_B$). The result showed that the values of kLa and a increased with the superficial gas velocity (Vg) and the size of bubble column. Influences of gas diffuser physical property (orifice size, thickness and orifice number) can be proven on the generated bubble size and the mass transfer performance in bubble column. Concerning the variation of $k_L$ coefficients with bubble size, 3 zones (Zone A, B and C) can be observed. For Zone A and Zone C, a good agreement between the experimental and the predicted $K_L$ coefficients was obtained (average difference of ${\pm}15%$), whereas the inaccuracy result (of ${\pm}40%$) was found in Zone B. To enhance the high $k_La$ coefficient and absorption efficiency in bubble column, it was unnecessary to generate numerous fine bubbles at high superficial gas velocity since it causes high power consumption with the great decrease of $k_L$ coefficients.

• Physical Therapy Korea
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• v.5 no.2
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• pp.47-64
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• 1998

The purposes of this research were to understand the realities of health management and to analyze the subjective, functional, psychological, and social health effects of the application of an exercise and education program to manage health on an elderly population residing in an agricultural community. The specific purposes of this research were: 1. to determine the subjective, functional, psychological health conditions, and performance level of instrumental activities of daily living of both the experimental and control groups before introducing a health management program, and then 2. to compare these with both the experimental and control groups' subjective, functional, psychological health condition and performance level of instrumental activities of daily living after applying the health management program. The health management program was introduced to the experimental group (50 people) but not to the control group (50 people). The health management program was composed of a health exercise program and a health education program. A comparative study of subjective health conditions was done to examine the effect of the health management program and the characteristics of health related variables before and after the program application. The results were as follows: 1. When the experimental group, which had received the 8-week health management exercise and education program, was compared with the control group, which had not, the experimental group's subjective health condition scored higher than that of the control group (p

• The Korean Society of Law and Medicine
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• v.10 no.2
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• pp.85-113
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• 2009

In this paper, the Judgment 2007DA76290 of the Korean Supreme Court was analysed in two points of the legal theory and litigation. The judgment arouses some issues of medical malpractice liability. They includes the concept of the complications and permanent lesion and the difference between them, some problems in a judge's applying the requirements for the physician's tort liability to the medical malpractice situations, the theory of obligation de moyens related with the burden of proof of the negligent conduct for a physician's liability for misperformance of contract, the influence of a patient's physical conditions on the physician's liability, the breach of duty to disclose in selecting the safer one of the treatment methods bringing about the complications or leaving the permanent lesion and so on. In the situations of the case referred to above, the plaintiff should have tried to establish that a reasonable physician in the specific situation of the case would have substituted the safer method of treatment for the method in the case. If the plaintiff had succeeded in establishing it, he or she could have recovered even the physical harm resulting from the permanent lesion brought about by the complications of the specific treatment in the case. The plaintiff failed to do so and recovered only the emotional distress which the patient suffered owing to the physician's breach of the duty to disclose. Therefore the legal malpractice of the counsel might be found in this case.

• Journal of Environmental Impact Assessment
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• v.21 no.6
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• pp.841-857
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• 2012

Preliminary ecological environmental assessments including physico-chemical constituents, water quality, fish fauna analysis, physical habitat health, and ecological health assessment were conducted as a primary step for Jeungchon micro-habitat ecosystem restoration in 2012. Water chemistry analysis of conductivity, dissolved oxygen, chlorophyll-a and etc. indicated that there were no significant differences(p < 0.05) among 6 sites between the headwaters and downstream. Multi-metric model analysis of Qualitative Habitat Evaluation Index(QHEI) showed that brooklets were at "good condition" as a mean QHEI of 158.7(n = 6) and the longitudinal differences of the model values between the sites were minor(QHEI range: 153 - 165). Total fish species and the number of individuals were 12 and 481, respectively, and dominant species were Zacco platypus(49.5%) and Zacco koreanus(36.8%). Tolerance guild analysis showed that the proportion of sensitive species($S_S$) had a negative linear function[$S_S=86.35-0.31(D_H)$; $R^2$ = 0.892, p < 0.01] with a distance from the headwaters, while the proportion of tolerant species($T_S$) had a positive linear function($R^2$ = 0.950, F = 90.28, p < 0.001) with the distance. Trophic feeding guild analysis showed that the proportion of insectivore species($I_n$) had a negative linear function($R^2$ = 0.934, p < 0.01) with a distance from the headwaters, while the proportion of omnivore species($O_m$) had a positive linear function($R^2$ = 0.958, p < 0.001) with the distance. Index of Biological Integrity(IBI) model, based on fish assemblages, showed a "fair condition" as a mean IBI of 23(n = 6), and there was a distinct differences of ecological health between the headwaters(S1 = 30; "good condition") and the downstreams(S6 = 14; "poor condition"). Overall, the preliminary environmental impact assessments suggest that water quality, physical habitat conditions(QHEI model), and ecological health(IBI model) were maintained well, even if the state was not an excellent conditions.

• Physical Therapy Korea
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• v.15 no.3
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• pp.1-7
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• 2008

Multi-sensory systems, including the visual, somatosensory, and vestibular ones, are involved in maintaining standing balance. The organization of these sensory systems is as important as the efficiency of each individual system in maintaining optimal balance. The purpose of the present experiment was to investigate the developmental changes in static standing balance and sensory organization under altered sensory conditions. This study involved 64 children (from 4 to 15 years of age) and 17 young adults. The children were divided into four age groups: 4~6, 7~9, 10~12, and 13~15 years. Static standing balance was assessed with the one-leg standing test under four different sensory conditions: the children stood on a firm surface with (1) eyes open or (2) closed, and they stood on a foam surface with eyes (3) open or (4) closed. In balancing ability, the age groups exhibited significant differences. The function of sensory organization for balance control was poorer for the children than for the young adults. The functional efficiency of the somatosensory system of the children aged 7~9 years was at the young adults' level, and the visual function of the children aged 10~12 years had also reached the young adults' level. However, the functional efficiency of the vestibular system of children was significantly lower than that of the young adults, even at the age of 15 years. This may indicate that sensory organization and standing balance are still developing after the age of 15 years.

• Journal of agricultural medicine and community health
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• v.18 no.2
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• pp.153-160
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• 1993

Health complaints among vinylhouse workers in Sungjoo county, Kyungpook province led to the investigation of heavy metal levels of air, soil and humans as well as physical conditions of the vinylhouse. The average temperature and humidity inside the vinylhouse were 8 higher and 10% point lower, respectively, as compared to the outside. While discomfort index(D. I.) outside was pleasant level(69.2), D. I. inside was 82 at which point 100% of people feels discomfort. Cadmium concentration of soils inside the vinylhouse(0.116 mg/kg) was 1.8 times higher than the soils outside. Arsenic concentration of soils inside the vinylhouse(4.882 mg/kg) was only slightly higher than the soils outside(4.182 ng/kg). However, both heavy metal concentrations detected in soils inside or outside the vinylhouse were within the normal range. Analysis of 10 air samples taken inside the vinylhouse showed that only one sample had a cadmium concentration above the detectable level and the rest of samples were below the detectable levels. While there were no difference of arsenic concentrations in urine between male and female, cadmium concentrations in urine samples of female (3.31 ug/l) was slightly higher than male(2.38 ug/l). Age-dependent increases of cadmium concentrations in urine samples were also observed. However, there was no concentration difference of these heavy metals in urine between vinylhouse workers and non-vinylhouse workers. Urine concentrations of cadmium and arsenic detected from vinylhouse workers or non-vinylhouse workers were within the normal range. The present study represents a first attempt to evaluate physical and environmental risk factors of the vinylhouse affecting the vinylhouse farmer's health. The study revealed that, while physical conditions of the vinylhouse such as temperature and humidity are the possible factors associated with the farmer's complaints, environmental contamination as judged from heavy metal levels in soil, air and humans is not a risk factor contributing to the vinylhouse farmer's health problem.

• Journal of International Academy of Physical Therapy Research
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• v.7 no.1
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• pp.938-948
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• 2016

In the present study, the general characteristics, job stress, working conditions, and aspects of pain of some industrial workers working in Changwon-si, Gyeongsangnam-do, were surveyed. In analyzing the relationship between job stress and the existence of pain, the variables "working speed" and "opportunities to develop abilities" were shown to have statistically significant relationships with the existence of pain ($p{\leq}.05$). Regarding the relationship between working conditions and the existence of pain, the variables" amount of work per hour," "amount of work per day," "number of parts handled during work," "work production per person," and" inconvenient postures or motions during work" were shown to have statistically significant relationships with the existence of pain($p{\leq}.05$). Regarding aspects of pain", within 1~3 years" was the most common answer to time of occurrence of symptoms, with a percentage of 27.6%; "appear almost always" was the most common answer to frequency of symptoms, with a percentage of 37.1%; "slight pain" was the most common answer to degree of pain, with a percentage of 50.5%; and "moderate" was the most common answer to encumbrance caused by pain to living and work, with a percentage of 41.2%. The aim of the present study was to determine the factors that affect pain due to musculoskeletal diseases in industrial workers and to define the aspects of pain in order to provide basic data for the preparation of measures to prevent musculoskeletal diseases. To control pain due to musculoskeletal diseases, factors that affect pain, as well as the aspects of pain, should be recognized early, and efforts should be made to supplement and improve systems for preventing recurrence.

• Korean Journal of Applied Biomechanics
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• v.27 no.1
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• pp.75-81
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• 2017

Objective: The purpose of this study was to compare and analyze the kinematic variables and electromyography (EMG) findings that change with varying characteristics of crouch start and feedback provision, and to provide the fundamental data for record improvement in 400 mH. Method: Four short-distance runners participated in the experiment. The analyzed variables were elapsed time per interval, stride length, and muscle activities in three lower limb muscles. These variables were analyzed by using Kwon3d XP and Noraxon Myoresearch. The participants were subjected to three conditions, including two conditions that relate to the thrusting foot on the rear block and another condition pertinent to feedback provision. Results: In terms of a one-step interval, the elapsed time in condition A was longer than that in condition B, and the one after the feedback was the longest. The stride length of a one-step interval was the longest in condition A. The stride length of a two-step interval was the shortest in condition A. The muscle activity during a one-step interval showed differences in vastus medialis and medial gastrocnemius, with condition A being the highest. Conclusion: When the non-dominant left foot was located at the back, negative results were observed in terms of elapsed time and stride length. Moreover, an imbalance in muscle activity was observed between the left and right feet when the left foot was placed at the back. As a result, significant differences in elapsed time, stride length, and muscle activity were observed depending on the foot placed on the rear block. In conclusion, we identified the characteristics of crouch start in 400 mH, and a specialized program must be suggested.

• Journal of the Korean Society of Physical Medicine
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• v.10 no.1
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• pp.63-69
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• 2015

PURPOSE: Low-intensity exercise with transient restriction of blood flow to muscle could be an alternative rehabilitation method which avoids the problems associated with conventional high-intensity exercise. However, the mechanism of low-intensity exercise with transient restriction of blood flow is not clearly known. Thus, the purpose of this study was to investigate the mechanism of improvement of muscular function after low-intensity exercise with transient restriction of blood flow using H-reflex analysis. METHODS: Twenty one healthy young adults with no medical history of neurological or musculoskeletal disorder voluntarily participated in this study. The ${\alpha}$-motor neuron excitability of the triceps surae was assessed using the H-reflex. The amplitude of the M-wave and H-reflex were measured across three conditions: rest, after low-intensity exercise without restriction of blood flow and after low-intensity exercise with restriction of blood flow. The subjects performed low-intensity ankle plantar flexion exercise at their own pace for one minute without or with transient restriction of blood flow achieved by a sphygmomanometer cuff on popliteal fossa at a pressure of 120mm of mercury(120 mmHg). RESULTS: No significant changes of the excitability of the ${\alpha}$-motor neuron were obtained across three different conditions. CONCLUSION: This study found that low-intensity exercise with transient restriction of blood flow did not influence to ${\alpha}$-motor neuron excitability of the triceps surae. From the results, I could come to the conclusion that further study will be required.

• Physical Therapy Rehabilitation Science
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• v.4 no.1
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• pp.32-37
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• 2015

Objective: This study was conducted to test the effects of mobile texting and gaming on gait with obstructions under different illumination levels. Design: Cross-sectional study. Methods: Twelve healthy adults aged 20 to 36 years (mean 23.5 years) were tested under six different conditions. All participants used touchscreen smartphones. Testing conditions included: 1) Walking with an obstruction under a bright illumination level; 2) walking with an obstruction with a low level of illumination; 3) walking with an obstruction while texting under a bright illumination level; 4) walking with an obstruction while texting with a low level of illumination; 5) walking with an obstruction while gaming under a bright illumination level; and 6) walking with an obstruction while gaming with a low level of illumination. All participants were asked to text the Korean national anthem by their own phone and play Temple Run 2 using an iPhone 5. Gait variances were measured over a distance of 3 m, and the mean value after three trials was used. A gait analyzer was used to measure the data. Results: Compared to normal gait with obstruction, gait speed, step length, stride length, step time, stride time, cadence while texting and gaming showed significant differences (p<0.05). Differences between the illumination levels included gait speed, step length, stride length, and step time (p<0.05) with no significant differences in stride time and cadence. Conclusions: Dual-tasking using a smartphone under low levels of illumination lowers the quality of gait with obstructions.