• Journal of the Korean Institute of Gas
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• v.20 no.3
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• pp.52-58
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• 2016

In this study, evaluation method for LNG plant FEED is suggested and its validity is confirmed using a well-known decision making technique of Analytic Hierarchy Process (AHP). It is a pairwise comparison technique which can be used when multiple options must be considered for a single decision making problem. In order to develop an objective decision methodology, various decision parameters, sub-parameters as well as the concept of scale of assessment were introduced, and its consistency among these parameters was also checked by calculating the consistency index (C.I.). The methodology suggested in this article will contribute in evaluation of LNG plant FEED with less bias and subjectivity associated with the decision making procedure.

• Smart Structures and Systems
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• v.19 no.2
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• pp.115-126
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• 2017

In this paper, size dependent bending and free flexural vibration behaviors of functionally graded (FG) nanobeams are investigated using a nonlocal quasi-3D theory in which both shear deformation and thickness stretching effects are introduced. The nonlocal elastic behavior is described by the differential constitutive model of Eringen, which enables the present model to become effective in the analysis and design of nanostructures. The present theory incorporates the length scale parameter (nonlocal parameter) which can capture the small scale effect, and furthermore accounts for both shear deformation and thickness stretching effects by virtue of a hyperbolic variation of all displacements through the thickness without using shear correction factor. The material properties of FG nanobeams are assumed to vary through the thickness according to a power law. The neutral surface position for such FG nanobeams is determined and the present theory based on exact neutral surface position is employed here. The governing equations are derived using the principal of minimum total potential energy. The effects of nonlocal parameter, aspect ratio and various material compositions on the static and dynamic responses of the FG nanobeam are discussed in detail. A detailed numerical study is carried out to examine the effect of material gradient index, the nonlocal parameter, the beam aspect ratio on the global response of the FG nanobeam. These findings are important in mechanical design considerations of devices that use carbon nanotubes.

• Smart Structures and Systems
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• v.19 no.2
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• pp.181-194
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• 2017

In order to investigate the interface debonding defects detection mechanism between steel tube and concrete core of concrete-filled steel tubes (CFSTs), multi-physical fields coupling finite element models constituted of a surface mounted Piezoceramic Lead Zirconate Titanate (PZT) actuator, an embedded PZT sensor and a circular cross section of CFST column are established. The stress wave initiation and propagation induced by the PZT actuator under sinusoidal and sweep frequency excitations are simulated with a two dimensional (2D) plain strain analysis and the difference of stress wave fields close to the interface debonding defect and within the cross section of the CFST members without and with debonding defects are compared in time domain. The linearity and stability of the embedded PZT response under sinusoidal signals with different frequencies and amplitudes are validated. The relationship between the amplitudes of stress wave and the measurement distances in a healthy CFST cross section is also studied. Meanwhile, the responses of PZT sensor under both sinusoidal and sweep frequency excitations are compared and the influence of debonding defect depth and length on the output voltage is also illustrated. The results show the output voltage signal amplitude and head wave arriving time are affected significantly by debonding defects. Moreover, the measurement of PZT sensor is sensitive to the initiation of interface debonding defects. Furthermore, wavelet packet analysis on the voltage signal under sweep frequency excitations is carried out and a normalized wavelet packet energy index (NWPEI) is defined to identify the interfacial debonding. The value of NWPEI attenuates with the increase in the dimension of debonding defects. The results help understand the debonding defects detection mechanism for circular CFST members with PZT technique.

• Journal of Agricultural Extension & Community Development
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• v.22 no.2
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• pp.159-173
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• 2015

The purpose of this study was to identify the conditions of neighborhood facilities for the elderly, paying special attention to the accelerated aging phenomenon in rural areas of Korea. We contrived a new index to measure spatial accessibility for people aged over 65 years, and we analyzed spatial accessibility by focusing on community facilities: public bath facilities, beauty shops, rural public facilities, markets, big stores, and large-scale retail shops. The most outstanding spatial accessibility among community facilities was found with the rural public facilities thanks to governmental installing adequate facilities in the past, followed by the beauty shops and the public bath facilities. In contrast, spatial accessibility of the markets was in the lowest. Spatial accessibility of community facilities for the elderly exhibited high variability among the rural areas. We confirmed significant inequality of spatial accessibility in all facilities we studied. The areas that had better spatial accessibility diverse combinations of the facilities. The areas that had worse spatial accessibility were, on the whole, consistent with traditional undeveloped regions. In the near future rational planning of facilities will be needed to supply adequate accessibility in targeted areas which currently had low accessibility. In order to improve the spatial accessibility of neighborhood facilities, the most essential factor is to take into account the geographical distribution patterns of rural settlements.

• KIEAE Journal
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• v.15 no.6
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• pp.101-109
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• 2015

Purpose: Glazing and shading devices influence a lot on the thermal and visual environment in office buildings. Solar heat and daylight are contrary concept, therefore proper arrangement of thermal and optical performance is needed when designing a glazing and shading devices. The purpose of this study is to examine the conditions of the glazing and shading devices available for promoting the reduction of cooling loads + lighting loads and the improvement in thermal comfort and visual comfort for the summer season in an office building installed with venetian blind. Method: This study established 12 simulation cases which have different glazings and the positions of venetian blind for evaluating different thermal and optical performance. And by using EnergyPlus v8.1 and Window v7.2 program, we quantitatively analyzed cooling loads + lighting loads, thermal comfort and visual comfort in an office building installed with the glazing and shading devices. Result: Consequently, Case 9(Double Low-E+Exterior Blind) is the best arrangement of solar heat gain and daylight influx, thereby becomes the most excellent case of reducing cooling+lighting loads(46.8%) and simultaneously becomes the enhancement case in thermal comfort. Also, DGI(Daylight glare index) under clear sky conditions in summer was evaluated to be 19.6, and thereby satisfied the recommendation level of allowing visual comfort.

• Journal of Korean Academy of Nursing
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• v.33 no.3
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• pp.312-320
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• 2003

Purpose: To investigate body compositons and bone mineral density(BMD) in college women and to find the relationship between them. Method: From January to March of 2001, BMD at four parts(forearm, lumbar, femur and whole body), body mass index(BMI), body fat mass(BFM), lean body mass(LBM) and body fat percentage(%Fat) were measured with the Dual Energy X-ray Absorptiometry. Other physical characteristics were measured with a scale, a height measurer, and questionnaires. Result: Grouping by the BMI, 43.2% showed low weight, and 5% over weight. When applying the percent Fat, 43.8 % was diagnosed as obesity group. The fact indicate that a majority of college women have unbalanced body composition with high percent Fat, compared to their body weight. Assessing the BMD with the WHO standards, 91.4～95.7% of the BMD of forearm and whole body was normal. But, 40.3% and 33.1～43.9% showed osteopenia at lumbar and femur, and 104 %, 0.7～7.2% showed osteoporosis. The BMD at all parts showed significant correlation each other(r=.29～.89, p=.001～.000). Body weight and BMI showed correlations to with BMDs at all parts of the body(r=.19～46, p=.025～.000; r=18～.45, p=.039～.000). But the percent Fat had a correlation with only femur neck BMD(r=.19, p=.024). Conclusion: This study showed a majority of healthy college women were exposed to the risk for osteoporosis. Additional study is required to develop nursing interventions to remove the risk factors of osteoporosis. In particular, the acquisition of balanced body composition is necessary, increasing body weight and BMI through the increase of LBM, not through the quantitative increase of BFM.

• Journal of Animal Environmental Science
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• v.6 no.3
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• pp.141-151
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• 2000

Over-grown seaweeds in Donghae(east sea of Korea peninsula) may impedes ocean environment, however, they can be a good nutrient resources for poultry feeds if they are utilized properly. In this study, seaweeds powder were tested for laying hens\` ration to investigate the effects on egg production rate, egg quality and calcium phosphorus excretion. One hundred 65wks-old brown layers were fed for 5 weeks alotted with seaweeds powder addition to experimental diet by 0(control), 0.5, 1.0 and 2.0%, respectively, and obtained following results; 1. Seaweeds proved a mid-protein low-energy feed resources with planty of K, Na, Ca, Mg, Sr and Fe. 2. Seaweeds addition by 0.5% and 1.0% improved egg production rate and egg-mass output markedly(p<0.05) than control. Seaweeds addition did not alter cholesterol level of yolk and yolk index, however egg shell thickness showed increasing trend by increasing seaweeds addition level. 3. Protein absorption and digestibility in seaweed addition treatments were significantly higher(p<0.05) than control group and protein contents of excreta in 0.5% and 1.0% treatments were reduced(p<0.05), which suggests effective protein metabolism for egg production. Increasing seaweeds addition reduces Ca and P contents in rectum and excreta, suggesting Ca and P utilization improvement in laying hens and lessening soil pollution. 4. In conclusion, seaweeds addition in layers' diet by 1.0% level improves egg-mass production and might be egg quality by increasing metabolism of protein, calcium and phosphorus.

• Journal of the East Asian Society of Dietary Life
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• v.8 no.2
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• pp.126-136
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• 1998

This study was designed to determine the effects of linoleic acid contents and $\omega$ 6/$\omega$3 ratios on the induction of gastric ulcer by water immersion and restraint stress. Sprague-Dawley rats were fed 5diets containing 7% fat(w/w) for 6weeks. These diet groups were Lh, Mh, Hh, Mm, Ml, : 3 different linoleic acid levels(0.3% of energy(L). 3.5(M), 10(H) and 3 different $\omega$6/$\omega$3 ratios (11(1), 33(m), 100(h) with beef tallow, sunflower or fish oil. The Lh group showed a significantly higher ulcer index (UI) than the Mh and Hh groups(p<0.05). At the same linoleic levels, the UI had no significant difference within the $\omega$6/$\omega$3 ratios. The Mh group showed significantly higher (p<0.05) PGE2 and TBX2 content than any other group. Pearson's correlation coeffcients between UI and PGE2 and TBX2 had a negatively significant correlation(p<0.05). Linoleic acid of gastric mucosal phospholipids was reflected by the diet, but was not significantly different. The most significant finding of this study is that not only the absolute amount of linoleic acid, but also the $\omega$6/$\omega$3 ratios are important factors for the prevention of gastric ulcer.

• Korean Journal of Community Nutrition
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• v.12 no.2
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• pp.160-167
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• 2007

This study was performed to investigate the effects of regular exercise on dietary factors and obesity indices among 407 healthy adult males subjects. Subjects were classified into regular exercise group (REG) and irregular exercise group (IREG). Two hundred and thirteen subjects of REG excercised regularly 3 times (more than 30 minutes/time) per week during more than last 1 month or more. One hundred and ninety-four of IREG (n = 194) didn't regularly exercise during the last 1 month. Obesity indices were BMI (Body Mass Index), WHR (Waist Hip Ratio) and PIBW (Percentage of Ideal Body Weight). And the mean BMI, WHR and PIBW of REG were (22.1, 0.90 and 105.8) significantly lower than those of IREG (25.7, 0.98 and 117.7) respectively. The mean daily starches, seeds, meats, eggs, fish, milk, fats and processed food intakes of REG were significantly lower than those of IREG And the mean daily vegetables, mushrooms and beverages intakes of the IREG were significantly lower than REG. Energy intake of REG and IREG were 1968.2 kcal and 1978.9 kcal respectively. Vitamin C intake of IREG was significantly lower than REG. But niacin and cholesterol intake of REG were significantly lower than the IREG. Exercise regularity was positively related with obesity indices and dietary factors. Therefore, it is necessary to exercise regularly to prevent obesity and cardiovascular disease in Korean adult males.

• Korean Journal of Community Nutrition
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• v.6 no.2
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• pp.227-233
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• 2001

The purpose of this study is to verify nutrient intake status and prevalence of obesity in vegetarians non-vegetarians and non-vegetarians. The vegetarian subjects consisted of 127 Buddhist nuns(age:23-79 yrs) from Oonmoon Temple on the Choungdo District of Gyeongsang Bookdo Province and 118 Buddhist nuns practicing Zen meditation at Soodeok Temple in Yeosan District of Chongcheong Namdoo Province. Control subjects were 235 healthy female adults aged from 23 to 79 years old. They were teachers and nurses at the hospital of Gyeongsang National University and housewives living in Chinju, Gyeingsang Namdoo Province. The study was conducted from October 1996 to February 1997, and consisted of a survey and anthropometric measurement. The results are summarized as follows : The average age of the subjects was 44.2 yrs for vegetarians and 40.5 yrs for non-vegetarians. The average body mass index(BMI) of vegetarians and non-vegetarians was 22.4 and 21.0, the waist hip ratio(WHR) was 0.8 and 0.8, and the percentage of body fat was 28.7 and 26.5 respectively. The average duration of vegetarian diet among vegetarians was 13.1 years. The nutrient intakes of vegetarians were above the RDA for all the nutrients expect calcium and vitamin A. The intakes of fat, cholesterol, saturated fatty acid and the energy ratio from fat among the vegetarians were significantly lower than those of the non-vegetarians(p〈0.01). However, the vegetarians consumed significantly higher amounts of fiber and vitamin C compared to the non-vegetarians(p〈0.01). Also, the ratio of dietary polyunsaturated fatty acid/saturated fatty acid was significantly higher in vegetarians. The prevalence of obesity was 13.9% for vegetarians and 11.9% for non-vegetarians by criteria of BMI 25 as obese.