• The Journal of the Acoustical Society of Korea
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• v.25 no.4
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• pp.191-196
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• 2006

Human tend to rely their information about the size of a space on vision. However, it might be a common experience to perceive a certain difference in spaces without any visual difference, in such spaces as rooms for music performance, multimedia environments with multiple sound sources, and car cabins, where auditory experiences have a certain importance. In the present work, apparent auditory room size was measured at different positions in a room through a series of listening experiments. Also, measurement of room acoustic parameters was carried out and their relationships with perceived auditory room size were analyzed. The results suggest that apparent auditory room sizes were largely dependent on musical clarity, distance between a source and a receiver, and sound pressure level at the listening position. Also, the results from acoustic preference test suggest that smaller apparent room sizes were preferred for listening to orchestral, cello and flute music. The relationship between apparent auditory room size and vocal music was found to be statistically insignificant.

• Geomechanics and Engineering
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• v.37 no.1
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• pp.49-64
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• 2024

Rocks undergoing repeated loading and unloading over an extended period, such as due to earthquakes, human excavation, and blasting, may result in the gradual accumulation of stress and deformation within the rock mass, eventually reaching an unstable state. In this study, a CNN-CCM is proposed to address the mechanical behavior. The structure and hyperparameters of CNN-CCM include Conv2D layers × 5; Max pooling2D layers × 4; Dense layers × 4; learning rate=0.001; Epoch=50; Batch size=64; Dropout=0.5. Training and validation data for deep learning include 71 rock samples and 122,152 data points. The AI Rock Constitutive Model learned by CNN-CCM can predict strain values(ε₁) using Mass (M), Axial stress (σ₁), Density (ρ), Cyclic number (N), Confining pressure (σ₃), and Young's modulus (E). Five evaluation indicators R², MAPE, RMSE, MSE, and MAE yield respective values of 0.929, 16.44%, 0.954, 0.913, and 0.542, illustrating good predictive performance and generalization ability of model. Finally, interpreting the AI Rock Constitutive Model using the SHAP explaining method reveals that feature importance follows the order N > M > σ₁ > E > ρ > σ₃.Positive SHAP values indicate positive effects on predicting strain ε₁ for N, M, σ₁, and σ₃, while negative SHAP values have negative effects. For E, a positive value has a negative effect on predicting strain ε₁, consistent with the influence patterns of conventional physical rock constitutive equations. The present study offers a novel approach to the investigation of the mechanical constitutive model of rocks under cyclic loading and unloading conditions.

• Journal of the Korean Society of Physical Medicine
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• v.19 no.1
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• pp.31-41
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• 2024

PURPOSE: This study examined the distribution dynamics and proposed determinants, including morphological measurements, clinical laboratory tests, and lifestyle factors among young Korean men aged 20 to 29 years with the coexistence of age-related loss of skeletal muscle mass and obesity (CALSMO). METHODS: Six hundred and sixty-six participants were divided into two groups based on their skeletal muscle mass index, with 12 individuals categorized in the CALSMO group and the remaining 654 in the normal group. The proposed determinants variables consisted of three main components: morphological measurements, clinical laboratory tests, and lifestyle factors. The morphological measurement variables were height, weight, body mass index, waist circumference, and skeletal muscle mass index. The clinical laboratory tests were fasting glucose, triglyceride, total cholesterol levels, and systolic and diastolic blood pressure. The lifestyle factors considered were alcohol consumption and tobacco use. Complex sampling analysis was performed for the evaluation. RESULTS: The distribution dynamics were determined to be 1.81(1.02-3.18) %. Morphological factors, such as height, weight, body mass index, waist circumference, and skeletal muscle mass index, showed significant differences (p < .05). The clinical laboratory test variables, specifically the fasting glucose, triglyceride, and total cholesterol levels, also exhibited significant differences (p < .05). The lifestyle factor, alcohol consumption, also showed a significance (p < .05). CONCLUSION: This study provides insights into the distribution dynamics. The proposed determinants in young Korean individuals with CALSMO are height, weight, body mass index, waist circumference, skeletal muscle mass index, fasting glucose, triglyceride, total cholesterol levels, and alcohol consumption.

• Korean Journal of Community Nutrition
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• v.12 no.5
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• pp.545-558
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• 2007

This study was performed to assess the sodium intakes of Korean adults using a 24-hr urine analysis and dish frequency questionnaire (DFQ) according to each dish group and the regional area. The subjects of this study were comprised of 522 adults (male : 267, female : 285), aged 20-59yr residing in the metropolitan area (N=200), Chungcheng-Do (N=117), Jeolla-Do(N=117), and Gueongsang-Do provinces (N=118). The subjects were recruited from the residents who once participated or are participating in the various health programs offered by the public health center. The number of subjects who completed the 24-hr urine collection was 205 (male : 110, female : 95). The mean age and BMI of the subjects were $39.0{\pm}$11.7y and $23.1{\pm}2.9 kg/m^2$, respectively. The mean systolic and diastolic blood pressure was $119.5{\pm}15.4 mmHg$, and $77.1{\pm}11.1 mmHg$, respectively. Eighteen percent of the subjects responded that they are currently smoking, 36% drinking and 50.4% exercising. Twenty point six percent of the subjects were assessed as having hypertension according to their systolic or diastolic blood pressure($SBP{\ge}140mmHg$ or $DBP{\ge}90mmHg$) measurements in the present study. Salt intake of the subjects estimated with 24-hr sodium excretion was 12.7g/d (male : 13.4g/d, female : 12.1g/d) based on the sodium excretion rate as 82%. Salt intake estimated with DFQ was 14.7g/d (male : 16.2g/d, female : 13.4g/d), 2 g more than the salt intake estimated with 24-hr urine analysis. The four dish groups that contributed most to the sodium intake in order were kimchi (11571.4mg), soup and stew (1260.5mg), fish and shellfish(706.3mg) and noodle and ramyeon(644.3mg). Salt intake estimated with DFQ was the highest in the subjects of Gueongsang-Do(17.0g/d), second highest Chungcheong-Do (16.4g/d) and the lowest in the metropolitan area (13.0g/d). Subjects of Gueongsang-Do showed the highest sodium intakes in most of the dish group, whereas subjects of the metropolitan area showed the lowest. Residents of Chungcheong-Do revealed the highest sodium intake with kimchi and of Jeolla-Do the higher sodium intake with main dish (meat, fish and beans). The highest salt percentage of kimchi ($3.0{\pm}0.8%$) and soybean paste ($14.5{\pm}5.1%$) were observed in Gueongsang-Do, whereas individuals of the metropolitan area were observed as having kimchi ($1.6{\pm}0.5%$) and soybean paste ($7.4{\pm}1.6%$) with the lowest salt percenage. Men were observed as having more salty kimchi ($2.4{\pm}0.1%$) than women ($2.1{\pm}0.1%$).

• The korean journal of orthodontics
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• v.30 no.2 s.79
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• pp.197-204
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• 2000

[$K^+$]-selective ion channels were studied in excised inside-out membrane patches from human osteoblast-like cells (G292). Three classes of $K^+$channels were present and could be distinguished on the basis of conductance. Conductances were $270\pm27\;pS,\;113\pm12\;pS,\;48\pm8\;pS$ according to their approximate conductances in symmetrical 140 mM KCl saline at holding potential of -80 mV It was found that the small conductance (48 pS) $K^+$channel activation was dependent on membrane voltage. In current-voltage relationship, small conductance $K^+$channel showed outward rectification, and it was activated by the positive potential inside the membrane. In recordings, single channel currents were activayed by a negative pressure outside the membrane. The membrane pressure increased $P_{open}$ of the $K^+$ channel in a pressure-dependent manner. In the excised-patch clamp recordings, G292 osteoblast-like cells have been shown to contain three types of $K^+$ channels. Only the small conductance (48 pS) $K^+$channel is sensitive to the membrane stretch. These findings suggest that a hyperpolarizing current, mediated in part by this channel, may be associated with early events during the mechanical loading of the osteoblast. In G292 osteoblast-like cells, $K^+$channel is sensitive to membrane tension, and may represent a unique adaptation of the bone cell membrane to mechanical stress.

• Journal of Nutrition and Health
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• v.41 no.8
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• pp.742-753
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• 2008

The purpose of this study is to investigate risk factors of pre-hypertension and hypertension in rural residents. Nine hundred and ninety four subjects aged 40-70 yrs in Chungnam-do participated in this study. The subjects (n = 824) were classified into three groups of hypertensive, pre-hypertensive, and normotensive according to the Joint National Committee (JNC)-7 criteria. The weight, body mass index (BMI), waist-hip ratio (WHR), and serum total protein, albumin, BUN, and triglyceride (TG) were positively correlated with SBP and DBP. After adjusted by age, sex and BMI, the total protein, albumin and TG were significantly correlated with SBP and DBP (p < 0.01). There was no significant difference in eating habits according to the level of blood pressure. The serum albumin, creatinine, Glu-FBS, Glu-PP l20, and triglyceride were higher in both prehypertensive and hypertensive group than in the normotensive group. However, mean serum cholesterol was not different among three blood pressure groups. In this study, the common risk factors of pre-hypertension and hyper-tension were male, age of fifties, lower education level, ex-smoking, higher drinking frequency, higher BMI, body fat %, waist circumference, WHR, serum albumin and diabetes, even though the degree of risks in these variables were higher in the hypertensive group. The higher BUN was a risk factor of prehypertension, while the family history, prediabetes, serum total protein, Glu-PP l20 and higher alcohol drinking amount were the risk factors of hypertension. This result suggests that maintaining good health habit and normal range of blood parameters as well as controlling body weight have to be paid attention in order to prevent hypertention, and further reseasch on the relationship of blood pressure and BUN are needed.

• Journal of the Korean Applied Science and Technology
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• v.34 no.4
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• pp.874-882
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• 2017

As the interest on the air-pollution is gradually rising up at home and abroad, automotiv e and fuel researchers have been working on the exhaust emission reduction from vehicles through a lot of approaches, which consist of new engine design, innovative after-treatment systems, using clean (eco-friendly alternative) fuels and fuel quality improvement. This research has brought forward three main issues : evaporative, performance, air pollution. In addition, researcher studied the environment problems of the bio-ethanol, bio-butanol, bio-ETBE (Ethyl Tertiary Butyl Ether), MTBE (Methyl Tert iary Butyl Ether) fuel contained in the fuel as octane number improver. The researchers have many dat a about the health effects of ingestion of octane number improver. However, the data support the con clusion that octane number improver is a potential human carcinogen at high doses. Based on the bio-fuel and octane number improver types (bio-ethanol, bio-butanol, bio-ETBE, MTBE), this paper dis cussed the influence of gasoline fuel properties on the evaporative emission characteristics. Also, this p aper assessed the acceleration and power performance of gasoline vehicle for the bio-fuel property. As a result of the experiment, it was found that all the test fuels meet the domestic exhaust gas standards, and as a result of measurement of the vapor pressure of the test fuels, the bio - ethanol : 15 kPa and the biobutanol : 1.6 kPa. thus when manufacturing E3 fuel, Increasing the biobutanol content reduces evaporation gas and vapor pressure. In addition, Similar accelerating and powering performance was shown for the type of biofuel and when bio-butanol and bio-ethanol were compared accelerated perf ormance was improved by about 3.9% and vehicle power by 0.8%.

• Journal of Nutrition and Health
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• v.40 no.5
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• pp.451-462
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• 2007

This study was conducted to investigate breakfast consumption pattern in relation to diet quality and health outcomes of Korean adults. Data are from 2001 National Health and Nutrition Survey. Dietary information of 3406 adults aged $30{\sim}49$ years and their socio-demographic characteristics, blood lipid profile, fasting blood glucose, blood pressure, anthropometric measurements were analyzed. According to the breakfast consumption of the subjects, they were classified to breakfast skippers and eaters and the eaters' breakfast staple types were defined as RICE, BREAD, NOODLES, MIXED (mixed types including several grain-based dishes), and OTHERS. The proportions of breakfast consumption patterns were 18.4% for skippers, 71.1% for RICE, 2.6% for BREAD, 1.6% for NOODLES, 4.0% for MIXED, and 2.4% for OTHERS. Breakfast skippers had lower daily nutrients intake than breakfast eaters but their health outcomes did not differ from those of eaters. Instead, men with BREAD pattern had higher blood cholesterol and women in NOODLE pattern had higher blood glucose and lower HDL cholesterol. The BREAD pattern breakfast had higher energy contribution from fat and lower nutrient densities and the subjects in BREAD pattern had higher level of household income. Men's BREAD pattern breakfast consisted more animal products than that of women. There was high probability of undernutrition among women in NOODLE pattern and their mean household income was the lowest. From these results, in Korea, breakfast staple types have different food patterns and there was need for developing healthy food patterns appropriate to each staple type. The breakfast consumption pattern had influences on nutrient adequacy of the diet and health outcomes and seemed to represent socio-economic status. These could be used in doing nutrition education in community.

• Tuberculosis and Respiratory Diseases
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• v.40 no.1
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• pp.16-22
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• 1993

Background: The Microbicidal and cytotoxic activities of neutrophils are to a large extent dependent on a burst of oxidative metabolism which generates superoxide anion, hydrogen peroxide, and other reactive products of oxygen. The respiratory burst of PMN is initiated by intracellular calcium mobilization that follows immune or particular stimulation and is very sensitive to modulation by c-AMP or adenosine. Despite its antagonism against adenosine, earlier study has demonstrated potent theophylline inhibition of the PMN respiratory burst at variable ranges of blood concentrations of theophylline in the healthy normal volunteers and in the septic animals pretreated or early post-treated with aminophylline (AMPH) or pentoxifylline. However it is unclear whether theophylline inhibits the superoxide generation or not in the established human sepsis caused by acute pneumonia, as taking into consideration of the fact that full activation of neutrophils have occurred within minutes after the septic insult in the animal experiments. Methods: We measured the $O_2$ generation of peripheral arterial neutrophils obtained from 11 human septic subjects caused by acute pneumonia before and 1 hour after completion of continuous AMPH infusion. Patients were identified and studied within 48 hour of admission. All subjects were administered an intravenous loading and maintenance dose of AMPH. The generation of $O_2$ was measured at a discrete time point (60 min) by the reduction of ferricytochrome c.PMA (10 ${\mu}g/ml$) was used as a stimulating agent. PMNs were isolated at a concentration of $2{\times}10^6$ cells/ml. The arterial oxygen tension, blood pressure and heart rates were also checked to evaluate the systemic effects of AMPH in the acute pneumonia. Results: The mean serum concentration of AMPH at 60 minutes was $8.8{\pm}0.6{\mu}g/ml$. Sixty minutes after AMPH infusion the generatition of $O_2$ was decreased from $0.076{\pm}0.034$ to $0.013{\pm}0.004$(OD) (p<0.05) and from $0.177{\pm}0.044$ to $0.095{\pm}0.042$(OD) (p<0.01) in the resting and stimulated PMNs respectively. $PaO_2$ was not changed after AMPH infusion. Conclusion: AMPH may compromise host defense by significant inhibition of neutrophil release of superoxide anion and it had no effect on improving $PaO_2$ in the acute pneumonia.

• Journal of the Korean Institute of Landscape Architecture
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• v.51 no.1
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• pp.72-84
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• 2023

The Rural Revitalization Strategy (2018-2022), published by the Chinese State Council in 2018, represents a new period of rural development in China. Suburban areas are more convenient than other rural areas in integrated urban-rural development but are under greater pressure from construction and industrial pollution. As a rural area with a high proportion of rural areas, it would be valuable for Henan province to gain a comprehensive grasp of rural human settlementst while identifying problems and proposing solutions. The purpose of this study is to analyze the satisfaction of the evaluation items based on the usage status and life perception of the residents of Tai Nan village, a suburb-type rural village in Henan province. The study proposes improvement programs based on the evaluation results. As a result of the study, 24 evaluation items were derived and divided into five categories: "Living Service Facilities", "Housing Environment, "Road Environment", "Health & Ecology Environment", and "Social & Cultural Environment". The Fuzzy Comprehensive Evaluation Method was used to find the overall satisfaction level of the human living environment in Tai Nan village, which was "average", among which "Living Service Facilities" was the most important "Health & Ecology Environment" was the least satisfied. Based on these results, an improvement plan is proposed in three stages. First, the living service will be improved while strengthening the facility management of the hygiene and the ecological environment. Second, reasonable improvement of housing and the road environment will be applied. Third, programs will be introduced to cultivate residents' ability to build their own and improve the social and cultural environment. This study provides basic data for the future improvement of rural settlements in the suburban areas of Henan province and is of great significance in gradually improving the the residents' quality of life.