• Journal of the Korean Applied Science and Technology
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• v.37 no.1
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• pp.17-27
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• 2020

The purpose of this study is to confirm the effects of a 6-week high-intensity combined training program on canoe athletes' cardiorespiratory function, isokinetic trunk strength, and anaerobic power. For the purpose of this study, the high-intensity combined training program was applied to 9 high-school canoe athletes. The high-intensity combined training program consists of aerobic exercise performed 2 times a week (Tuesday and Thursday), anaerobic exercise performed 3 times a week (Monday, Wednesday, and Friday), and flexibility exercise performed 5 times a week. The core of the high-intensity combined training program was the anaerobic training program performed with 100% weight for repetition; otherwise, the existing training method was divided into the percentage (%) of the 1RM. The aerobic exercise and the gym ball exercise are performed subsidiarily. Results showed that there was a statistically significant difference in height and muscle mass, whereas there was no statistically significant difference in weight, body fat percentage, and BMI followed by the high-intensity combined training program. There were statistically significant differences in maximum oxygen uptake and total exercise time. The angular velocity of 30°/sec showed a statistically significant difference in the peak torque item of flexors only. Also, the angular velocity of 120°/sec showed a statistically significant difference in the total work item of extensors only; however, there was no statistically significant difference in all the items of peak power, average power, and peak drop. In conclusion, it seems that the high-intensity combined training program may be applied as a training program for enhancing canoe athletes' performance. For further studies, more than 6 weeks training program with more participants would show improved results of isokinetic strength and anaerobic power in athlets.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.45 no.2
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• pp.185-198
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• 2019

Human tissue undergoes aging by the oxidant damage via structural change and its physical properties. The skin aging process is well known and many evaluations have been conducted. However, studies on hair aging were relatively few and thus care for aging hair is difficult. This study aims to fabricate an aging hair and identify anti-aging effect with known ingredient in anti-aging. First of all, physical properties of aging hair of age 60s by physiologically intrinsic factors were compared to those of the hair made by various extrinsic factors such as several chemical reactions and iteration numbers of the treatments. The extrinsic aging hair of this study relates to the less amount of lipid and to the hair of perm treated once accordingly, wherein several physical properties, preferably comprise roughness and tensile strength, present a novel concept of the intrinsic aging hair. The penetration of peptide into the aging hair was leading the extrinsic hair towards more structurally directed a younger hair. In addition to the structural change, the penetration of the peptide enhanced texture and tensile strength of the aging hair. These patterns have been also found in addition of propolis. For the first time, these qualitative studies exhibit that indeed our extrinsic aging hair well describes the anti-aging efficacy as a receptor for a cross-linker and the ingredients of human hair.

• Journal of Korean Society of Forest Science
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• v.33 no.1
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• pp.33-58
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• 1977

A bark comprises about 10 to 20 percents of a typical log by volume, and is generally considered as an unwanted residue rather than a potentially valuable resourses. As the world has been confronted with decreasing forest resources, natural resources pressure dictate that a bark should be a raw material instead of a waste. The utilization of the largely wasted bark of genus Pinus, Quercus, and Populus grown in Korea can be enhanced by learning its physical and mechanical properties. However, the study of tree bark grown in Korea have never been undertaken. In the present paper, an investigative study is carried out on the bark of three genus, eleven species representing not only the major bark trees but major species currently grown in Korea. For each species 20 trees were selected, at Suweon and Kwang-neung areas, on the same basis of the diameter class at the proper harvesting age. One $200cm^2$ segment of bark was obtained from each tree at brest height. Physical properties of bark studied are: bark density, moisture content of green bark (inner-, outer-, and total-bark), fiber saturation point, hysteresis loop, shrinkage, water absorption, specific heat, heat of wetting, thermal conductivity, thermal diffusivity, heat of combustion, and differential thermal analysis. The mechanical properties are studied on bending and compression strength (radial, longitudinal, and tangential). The results may be summarized as follows: 1. The oven-dry specific gravities differ between wood and bark, further more even for a given bark sample, the difference is obersved between inner and outer bark. 2. The oven-dry specific gravity of bark is higher than that of wood. This fact is attributed to the anatomical structure whose characters are manifested by higher content of sieve fiber and sclereids. 3. Except Pinus koraiensis, the oven-dry specific gravity of inner bark is higher than that of outer bark, which results from higher shrinkage of inner bark. 4. The moisture content of bark increases with direct proportion to the composition ratio of sieve components and decreases with higher percent of sclerenchyma and periderm tissues. 5. The possibility of determining fiber saturation point is suggested by the measuring the heat of wetting. With the proposed method, the fiber saturation point of Pinus densiflora lies between 26 and 28%, that of Quercus accutissima ranges from 24 to 28%. These results need be further examined by other methods. 6. Contrary to the behavior of wood, the bark shrinkage is the highest in radial direction and the lowest in longitudinal direction. Quercus serrata and Q. variabilis do not fall in this category. 7. Bark shows the same specific heat as wood, but the heat of wetting of bark is higher than that of wood. In heat conductivity, bark is lower than wood. From the measures of oven-dry specific gravity (${\rho}d$) and moisture fraction specific gravity (${\rho}m$) is devised the following regression equation upon which heat conductivity can be calculated. The calculated heat conductivity of bark is between $0.8{\times}10^{-4}$ and $1.6{\times}10^{-4}cal/cm-sec-deg$. $$K=4.631+11.408{\rho}d+7.628{\rho}m$$ 8. The bark heat diffusivity varies from $8.03{\times}10^{-4}$ to $4.46{\times}10^{-4}cm^2/sec$. From differential thermal analysis, wood shows a higher thermogram than bark under ignition point, but the tendency is reversed above ignition point. 9. The modulus of rupture for static bending strength of bark is proportional to the density of bark which in turn gives the following regression equation. M=243.78X-12.02 The compressive strength of bark is the highest in radial direction, contrary to the behavior of wood, and the compressive strength of longitudinal direction follows the tangential one in decreasing order.

• Journal of the Korea Concrete Institute
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• v.19 no.1
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• pp.121-130
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• 2007

To investigate the enhancement in strength and deformation capacities of concrete confined by FRP composites, tests under axial loads were carried out on three groups of thirty six short columns in circular section with diverse GFRP confining reinforcement. The major test variables considered include fiber content or orientation, wrap or tube type by varying the end loading condition, and continuous or discontinuous confinement depending on the presence of vortical spices between its two halves. The circumferential FRP strains at failure for different types of confinements were also investigated with emphasis. Various analytical models capable of predicting the ultimate strength and strain of the confined concrete were examined by comparing to observed results. Tests results showed that FRP wraps or tubes provide the substantial increase in strength and deformation, while partial wraps comprising the vertical discontinuities fail in an explosive manner with less increase in strength, particularly in deformation. A bilinear stress-strain response was observed throughout all tests with some variations of strain hardening. The failure hoop strains measured on the FRP surface were less than those obtained from the tensile coupons in all tests with a high degree of variation. In overall, existing predictive equations overestimated ultimate strengths and strains observed in present tests, with a much larger scatter related to the latter. For more accuracy, two simple design- oriented equations correlated with present tests are proposed. The strength equation was derived using the Mohr-Coulomb failure criterion, whereas the strain equation was based on entirely fitting of test data including the unconfined concrete strength as one of governing factors.

• Journal of Korean Tunnelling and Underground Space Association
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• v.20 no.3
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• pp.543-560
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• 2018

With the increased development in downtown underground space facilities that vertically cross under a railway at a shallow depth, the demand for non-open cut method is increasing. However, most construction sites still adopt the pipe roof method, where medium and large diameter steel pipes are pressed in to form a roof, enabling excavation of the inside space. Among the many factors that influence the loosening region and loads that occur while pressing in steel pipes, the size of the pipe has the largest impact, and this factor may correspond to the magnitude of load applied to the underground structure inside the steel pipe roof. The super equilibrium method (SEM) has been developed to minimize ground disturbance and loosening load, and uses small diameter pipes of approximately 114 mm instead of conventional medium and large diameter pipes. This small diameter steel pipe is called an SEM pile. After SEM piles are pressed in and the grouting reinforcement is constructed, a crossing structure is pressed in by using a hydraulic jack without ground subsidence or heaving. The SEM pile, which plays the role of timbering, is a fore-poling pile of approximately 5 m length that prevents ground collapse and supports surface load during excavation of toe part. The loosening region should be adequately calculated to estimate the spacing and construction length of the piles and stiffness of members. In this paper, we conducted a comparative analysis of calculations of loosening load that occurs during the press-in of SEM pile to obtain an optimal design of SEM. We analyzed the influence of factors in main theoretical and empirical formulas applied for calculating loosening regions, and carried out FEM analysis to see an appropriate loosening load to the SEM pile. In order to estimate the soil loosening caused by actual SEM-pile indentation and excavation, a steel pipe indentation reduction model test was conducted. Soil subsidence and soil loosening were investigated quantitatively according to soil/steel pipe (H/D).

• Childhood Kidney Diseases
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• v.6 no.2
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• pp.188-197
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• 2002

Purpose : Nowadays, drinks, foods and snacks have frequently been intensified with calcium and the insights into the importance of calcium-intake in general has developed in Korea. In this decade, we found the numbers of children who was visited to our hospital for evaluation of hematuria defined with hypercalciuria were increased. So we tried to compare the mean levels of serum calcium, alkaline phosphate, sodium, potassium, chloride, BUN, creatinine, bicarbonate and urinary pH who visited our hospital in 1991, 1992 with in 2000, 2001. Materials and methods : Between January 1991 to December 1992, and between January 2000 to December 2001, each 366 children and 488 children, aged 1 month to 15 years, who presented in our hospital for tonsilectomy and adenoidectomy or for inguinal herniorrhaphy were enrolled in the study, The children in the study were checked the level of serum calcium, alkaline phosphate, sodium, potassium, chloride, BUN, creatinine, bicarbonate and urinary pH with the machine which was corrected the similar levels of practical chemical levels in serum. We compared each mean levels in 1991s' group with in 2001s' group totally and separately through the age and sex. We used t-test to analysis data. Results : The levels of serum calcium, alkaline phosphate, creatinine, sodium, potassium, and urinary pH of 2001s' group were significantly higher than the levels of 1991s' group(P<0.05). The each level was $9.91{\pm}0.50\;mg/dL,\;248.58{\pm}94.98\;U/L,\;0.61{\pm}0.14\;mg/dL,\;138.64{\pm}2.22\;mM/L,\;4.35{\pm}0.40\;mM/L,\;6.18{\pm}0.86$ in 2001s' and $9.13{\pm}0.68;mg/dL,\;198.26{\pm}79.34\;U/L,\;0.433{\pm}0.18\;mg/dL,\;137.86{\pm}2.67\;mM/L,\;4.22{\pm}0.36\;mM/L,\;5.83{\pm}0.95$ in 1991s'. And the levels of serum bicarbonate, $23.64{\pm}2.57\;mM/L$ in 2001s' was significantly lower than the 1991s', $24.60{\pm}2.23\;mM/L$(P<0.05). The similar results were detected each age and sex group. Conclusion : The levels of serum calcium increase in this decade. The results will be used as a basic data for the national health plan in the years to come.

• Membrane Journal
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• v.24 no.3
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• pp.194-200
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• 2014

The purpose of this study was to evaluate the performance of newly developed Large Pore Micro-Filtration (LPMF) membrane in Lab size for the application of water treatment, and to find its problems with solutions. The out-to-inside filtration hollow fiber LPMF membrane of which average pore size was $5{\mu}m$ was used at this study and its material was the PET braid reinforced PVDF. Filtration tests were done through gravity with 30 cm water head difference or pressure below 1.5 bar, and the backwash was done instantaneously with the filtrate after pressurizing it to about 4 bar. The water flux of the LPMF membrane with 0.2 bar TMP (Trans Membrane Pressure) was 2 times higher than $0.4{\mu}m$ MF membrane with $0.05{\mu}m$ UF filtrate of the tap water and it was measured also with 20~30 cm water head difference which showed over 800 LMH at 30 cm water head difference. And Time-To-Filter (TTF) was performed by using $5{\mu}m$ filter paper to optimize coagulants and dosage which enhanced filtrate's turbidity and stabilized filtration flux. When the LPMF was operated with 30 cm gravity with very high dose of inorganic coagulants, the flux was maintained over 80 LMH with 93.5~99.5% turbidity removal. Especially, the filtration was maintained stably in the flux and about 97% of the recovery rate by instantaneous pressurized backwash with about 4 bar of the filtrate when the packing density was about 19%. But there was instability in filtration, since the TMP was continuously going up by inefficient backwash when the packing density was 43%.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.6
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• pp.720-726
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• 2007

This study was performed to investigate effects of raw sea tangle products on idiopathic constipation. A total of thirty-eight women participated voluntarily in this study. They were placed into one of four groups by their total colonic transit time (TCTT) to make the four groups have the same TCTT. In the first trial, the subjects in Control group were fed 3 times of 150 mL of mineral water per day for 2 weeks, those in +Control group were fed a kind of stool softener as well as the same mineral water for 3 times, those in STT group were fed 3 times of 150 mL of sea tangle tea and those in STB group were fed 3 times of 150 mL of sea tangle beverage. After 6 weeks, a second trial was performed for another 2 weeks. Although the TCTT of the group exposed to of KolomarkTM was not significantly reduced, the subjects in STT group answered that their evacuation activities were significantly improved; evacuation frequency was increased, stool hardness was reduced, evacuation straining was lessened, stool amount was increased, incomplete sense of evacuation was lessened, and major evacuation time was improved like those in +Control group. The results imply that it is worthy to develop some products of raw sea tangle such as STT, which are effective in treating or preventing constipation.

• Radiation Oncology Journal
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• v.25 no.4
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• pp.193-200
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• 2007

Purpose: This study evaluated the pretreatment expression patterns of MDM2, p53, and pRb proteins to determine if the expression patterns could predict the outcome of concurrent chemoradiotherapy (CCRT) for esophageal squamous cell carcinoma and aid in the decisions for the selection of treatment modalities. Materials and Methods: Fifty-one patients that were treated with definitive chemoradiotherapy for stage $I{\sim}IVa$ esophageal squamous cell carcinoma were selected for this study. Radiotherapy was administered with daily $1.8{\sim}2\;Gy$ fractions up to a median dose of 54 Gy for primary tumors, and with four cycles of cisplatin/5-fluorouracil chemotherapy that was administered every 4 weeks, the first two cycles of which were administered concurrently with radiotherapy. Expression of MDM2, p53, and pRb was investigated by immunohistochemical analysis using pretreatment biopsy specimens. Results: MDM2, p53, and pRb were detected with high immunoreactivity in 19.6%, 27.5%, and 66.7% of the patients, respectively. However, there was no significant correlation between expression of these factors and clinical outcome. By the use of multivariate analysis with nine covariates-age, tumor location, tumor length, stage, pathological response, clinical response, MDM2 expression, p53 expression, and pRb expression, only pathological response and stage were significant factors for cause-specific survival. Conclusion: Expression of MDM2, p53, and pRb was not found to be clinically significant for predicting outcomes after CCRT in this study. Further studies with a larger patient population and longer follow-up periods are needed to re-evaluate the expression pattern and to identify new predictors for CCRT response.

• Journal of Animal Science and Technology
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• v.46 no.4
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• pp.593-602
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• 2004

A feeding trial was carried out to investigate the effect of supplemental complex probiotics on performances, physio-chemica1 properties of meat and inetestinal microflora in broiler chicks. Four hundred eighty broiler chickens, one days old with mixed sexes were fed one of four diets containing 0, 0.1, 0.2 and 0.4% complex probiotics for 7 weeks. There were four replicates with thirty chicks per pen. Diet contained ME 3,100, 3,l00kcal/kg, and CP 22.0, 20.0% for starting and finishing period, respectively. Body Weight gain of chicks fed the complex probiotics tended to increase from the frist week and all complex probiotics higher than control from the 4th week. Chickens fed the diets containing 0.2% probiotics had higher(P<0.05) than those fed the other levels from the 4th week to 5th week. Feed conversion also improved significantly(P<0.05) in the supplemental 0.2% probiotics from the 4th week to 5th week. In physio-chemica1 properties of meat, carcass rate increased significantly(P<0.05) in the supplemental 0.4% probiotics compared to that of control at 7 weeks overall means and abdominal fat pad rate increased significantly(P< 0.05) in the supplemental 0.2% probiotics compared to that of control. Cooking loss decreased significantly(P<0.05) in the supplemental all probiotics. But shear force increased significantly(P<0.05) in the supplemental 0.4% probiotics. The number of ileum and cecum Lactobacillus spp. tended to increase in the supplemental complex probiotics at 7 week of age, but was not significantly different. As the result, supplemental complex probiotics increased performance and physio-chemica1 properties of meat and the number of intestinal Lactobacillus of broiler chicks.