• KSCE Journal of Civil and Environmental Engineering Research
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• v.8 no.2
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• pp.109-116
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• 1988

The strength and load of structure are varied with the Passage of time, and become a process of probability. It is possible to estimate the reliability from the relation between strength and load. Considering the safety, It is reasonable to estimate allowable stress from the safety factor based on the reliability. In this study, the method to estimate probability of fracture, which is index of reliability for rail subjeict to long term fatigue load were examined. In estimation of reliablity it is meaningless to evaluate numerical value especially this difficult case estimating parameter of random variable. To overcome this problem, conventional design method estimating relative reliability were proposed. In this study the Cornell method were examined. The uncertainity of random variale, ie coefficient of variation which is the index of variation of strength and load were considered. The effect of uncertainity related to probability of fracture, and safety factor based on reliability were examined. The results of this study are followed. The reliability of weld metal were influenced by variation of strength more then load, and base metal were influenced by load. It is confirmed that the allowable stress range calculating with factor of safety based an reliability is conservative.

• Journal of Distribution Science
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• v.13 no.10
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• pp.123-133
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• 2015

Purpose - The Korean government has devised intermodal transportation policies and granted subsidies to shippers and logistics companies that made a conversion of transportation means through the policies. This provides support by expanding the complex uniform railroad transportation and overhauling the deteriorated railroad facilities. As for 2013, however, the freight transportation percentage of railroad was 4.5% in tons and 8.5% in ton kilometers. Meanwhile, since the 1990s, developed countries such as the U.S. and Europe have been trying to expand intermodal freight transport with a legal and institutional support to build a logistics system corresponding with social and economic environmental changes. In this study, I set out to examine the effects of the intermodal freight transport policies in the EU and the U.S., and to explore the direction of setting up a rail intermodal transport system in South Korea. Research design, data, and methodology - The paper used a qualitative research methodology through the literature review. First, was an overview of Intermodal transportation in the EU, U.S. and UN. Second, it describes the development of transport in Europe and the U.S. with particular emphasis on intermodal freight transport. Third, it explores the direction of setting up a intermodal freight transport in South Korea. The last section contains concluding remarks. Results - As for the EU, it has been promoting integration between transport and intermodal logistics network designs while utilizing ITS or ICT and supports for rail freight intermodal by giving reduction to a facilities fee or subsidizing for rail freight in order to minimize the cost of external due to freight transport. On the other hand, as for the U.S., it has been made up of an industrial-led operating project and has been promoting it to improve accessibility between intermodal hubs and cargo terminals through intermodal corridor program, and an intermodal cargo hub access corridor projects, etc. Moreover, it has tried to construct intermodal transport system using ITS or ICT and to remove Barrier. As a result, in these countries, the proportion of intermodal freight transport is going to be the second significant transport compared with rail and maritime transport. An Effective rail intermodal transport system is needed in South Korea, as seen in the case of these countries. In order to achieve this object, the following points are required to establish radical infrastructure policy; diversify investment financing measures taken under public-private partnerships, legal responsibilities, improvement of utilization of existing facilities to connect the railway terminal and truck terminal, and enhancement service competitiveness through providing cargo tracking and security information that combines the ITS and ICT. Conclusions - This study will be used as a basis for policy and support for intermodal freight transport in South Korea. In the future, it is also necessary to examine from the perspective of the shipper companies using the rail intermodal transport, ie, recognition of shipper, needed institutional supports, and transportation demand forecasting and cost-effective analysis of the railway infrastructure systems improvement.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.12 no.4
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• pp.297-303
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• 1979

Early morphological changes of Omobranchus slogans (STEINDACHNER) (Family Blennidae) were studied based on the samples of 125 individuals collected from Changseon channel of Nam-hae in June 1973 and May 1979. Descriptions were made with particular emphasis on developmental changes of supraorbital region, fin rays, development of chromatophores and the preopercular spine. In the early stages the lateral profile of the supraorbital region is perpendicular to tile sagittal plane, however, in the later stages it becomes curved. In the early stage of 5.55 mm in total length the number of soft rays of dorsal fin is 18, and that of the anal fin 15. Ventral fin first appears as a premoidal proturberance. It fully developes into a fin composed of two soft rays in the stages of 12.9 mm in total length. The caudal fin rays first appear in the ventral part and in the stages of 6.15 mm in total length it gets one or two soft rays which bear 1-2 segments. In the later stages each ray bears more than 5 segments. Melanophores first appear as two black spots on the central part of the head. They are distributed on the opercle and the antero-dorsal surface of the trunk in the stage of 18mm in total length. At this stage the general chromatophore. pattern is identical to the adult stage. The anal fin bears melanophores at the basal part of the rays, and it is one of the remarkable morphological characters of this species. In early stages the preopercular spine develops reaching the basal part of the pectoral fin. In the later stages of 15 mm in total length relative length of the spine decreases to total length, and ie reaches only the distal margin of the opercular.

• Environmental Analysis Health and Toxicology
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• v.20 no.3 s.50
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• pp.195-203
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• 2005

Cytochrome P45O 17$\alpha$-hydroxylase (CYPI 7) and cytorhrome P45O aromata.ie (CYPI 9) are key steroidogenic enzymes in androgen and estrogen synthesis. ThiL study evaluated the effects of nonylphenol (NP) on CYP17 and CYP19 expression in the ovary of Sprague-Dawley rats. All female rats were administered orally with the vehicle (control, corn oil), diethylstilbestrol (DES, 5.0 $\mu$g/kg) and NP (50, 100, or 200 mg/kg/day), which was startinB when they were weaned at 21 days of age for 20 days. Twenty four hours after final dose, the animals were anelthetized with ether. Significant decreases in the uterus (wet weight) were observed with 5.0 $\mu$g/kg/day DES (78$\%$, of control) and 200 mg/kg/day NP (62$\%$ of control), respectively Additionally, ovarian weight was significantly decreased with 5.0 $\mu$g/kg/day DES (63$\%$ of control) and 200 mg/kg/day NP (72$\%$ of control). The serum estradiol levels were sligHtly lower in DES and high dose NP treatment groups, but the 74 levels were not affected by DES and NP. The expression of the ovarian CYP19 gene increased with low doses (50 and 100 mg/kg/day) of NP. while DES and high dose oi NP (200 mg/kg/day) did not affect on the CYP19 mRNA levels. In contrast to the CYP19 gene, the CYP17 gene expreLsion level was significantly down-regulated by the DES and 200 mg/ks/day NP. This result suggestE that NP inhibits ovarian estrogen synthelis by supprelsing CYP17 mRNA efprelsion, And different mechanisml might exist for the expression of Lteroidogenic CYP17 and CYP19 genes in the ovary of Sprague-Dawley rats in response to NP.

• Korean Journal of Head & Neck Oncology
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• v.25 no.2
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• pp.128-131
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• 2009

Objectives : Mucosa-associated lymphoid tissue(MALT) lymphoma of the head and neck region is relatively rare, but it has variable clinical and biological characteristics. Although there were few studies on this topic, there is still controversy regarding the best treatment. The authors retrospectively investigated the clinical courses and treatment results in 10 patients presenting with MALT-lymphoma in head and neck region except ocular adnexa. Material and Methods : Ten patients with a histologically verified diagnosis of the extranodal marginal zone B cell lymphoma arising in thyroid glands(3), larynx(3), oral cavity(2), oropharynx(1), salivary glands(1) were analyzed. Results : Four patients were allocated to stage IE and another six patients to stage IIE according to the Ann Arbor staging system. Treatment consisted of local therapy(surgical resection and/or radiotherapy) in four patients and systemic chemotherapy with/without local therapy in six patients. Complete remission and partial remission were achieved in seven patients(70%) and two patients(20%), respectively. No recurrence or mortality was observed with a mean follow-up of 40.5 months. Conclusion : Patients with MALT-lymphomas of the head and neck region were potentially treated by local modality in localized disease state. However systemic chemotherapy was also effective even in localized disease state and was well tolerated by patients. And strict staging and close long-term monitoring were recommended considering its indolent progression.

• Horticultural Science & Technology
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• v.18 no.3
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• pp.368-372
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• 2000

The fruit structure of 'Fuji' apples from full bloom to maturing was observed from 1997 to 1998. Cell division period of the fruit was found to be 4 to 5 weeks after full bloom. Vascular bundles in the inner part of the fruit skin which were not described in the books illustrating apple fruit structure was observed, as they were tentatively named as outer vascular bundles (OVB), and another vascular bundles were also observed newly in periphery of locules, as they were tentatively named as inner vascular bundles (IVB). In the observation of the inner epidermis (IE) in the inner part of the locules on 2 days prior to full bloom, the guard cells were observed and these were disappeared in the observation made 2 days later, i.e. on full bloom. The formation of fruit skin was observed at the microscope 65 days after full bloom and the number of cell which organized the fruit skin did not change from this time to maturation period. Tannin which is mainly in the fruit skin changing from continuously during fruit growth, specially the tannin of epidermis disappeared completely 100 days after full bloom stage, and then constituted again. Starch was not almost found out in cell division period of fruit from full bloom stage after this time it constituted much at flesh part and decreased at maturation period. Epidermis was developed by uniform cells of a layer the cell of epidermis constituted irregularity after pigmentation stage, the organization of fruit was not close because the very big intercellular space constituted at hypodermis and flesh structure.

• The Korean Journal of Food And Nutrition
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• v.29 no.5
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• pp.724-734
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• 2016

The purpose of this study was to determine the health behaviors and nutritional status related to dyslipidemia in Korean middle-aged adults (between 50 and 64 years old) from the Korean National Health and Nutrition Examinations Survey data (2007~2010). A total of 4,721 subjects were analyzed in this study. The subjects were divided into three groups (normal, borderline, and dyslipidemia) according to serum lipid levels. Parameters included in this study were drinking and smoking, anthropometric parameters, blood and nutritional parameters. The latter parameter included food/nutrients intake. All data was adjusted by sex, region, education level, and age. General linear model and logistic regression model were used for statistical analysis. The dyslipidemia group was comprised of more men than women. By contrast, the borderline group was comprised of more women than men (p<0.001). No significant differences were observed for other general characteristics. There were more smokers and drinkers(drinking per time) in the dyslipidemia group (p<0.05). Anthropometric data showed significant difference, ie, height (p<0.05), weight, body mass index, waist circumference, percent body fat, and blood pressure were higher in the dyslipidemia group (p<0.001). Only blood urea nitrogen showed no significant difference among groups. The HbA1c (p<0.01), fasting blood glucose, GOT, GPT, creatinine levels were higher in the dyslipidemia group (p<0.001). So it is required for the management of obesity in dyslipidemia group. The dyslipidemia group ate less sea food (p<0.05). The nutrients intake of energy and protein, thiamin, riboflavin, niacin, calcium, phosphorus were lower in the dyslipidemia group (p<0.05). Therefore, to lower dyslipidemia prevalence rates, it is necessary to increase the intake of foods containing ${\omega}-3$ fatty acids. We also suggest a meal management program and nutritional education to recognize the risk of dyslipidemia, especially for people such as the individual in the borderline and dyslipidemia study groups.

• Journal of the Society of Naval Architects of Korea
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• v.29 no.4
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• pp.114-131
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• 1992

In the present work, a two-dimensional boundary-value problem for a large amplitude motion is treated as an initial-value problem by satisfying the exact body-boundary and nonlinear free-surface boundary conditions. The present nonlinear numerical scheme is similar to that described by Vinje and Brevig(1981) who utilized the Cauchy's theorem and assumed the periodicity in the horizontal coordinate. In the present thesis, however, the periodicity in the horizontal coordinate is not assumed. Thus the present method can treat more realistic problems, which allow radiating waves to infinities. In the present method of solution, the original infinite fluid domain, is divided into two subdomains ; ie the inner and outer subdomains which are a local nonlinear subdomain and the truncated infinite linear subdomain, respectively. By imposing an appropriate matching condition, the computation is carried out only in the inner domain which includes the body. Here we adopt the nonlinear scheme of Vinje & Brevig only in the inner domain and respresent the solution in the truncated infinite subdomains by distributing the time-dependent Green function on the matching boundaries. The matching condition is that the velocity potential and stream function are required to be continuous across the matching boundary. In the computations we used, if necessary, a regriding algorithm on the free surface which could give converged stable solutions successfully even for the breaking waves. In harmonic oscillation problem, each harmonic component and time-mean force are obtained by the Fourier transform of the computed forces in the time domain. The numerical calculations are made for the following problems. $\cdot$ Forced harmonic large-amplitude oscillation(${\omega}{\neq}0,\;U=0$) $\cdot$ Translation with a uniform speed(${\omega}=0,\;U{\neq}0$) The computed results are compared with available experimental data and other analytical results.

• International Journal of Highway Engineering
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• v.10 no.4
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• pp.9-18
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• 2008

Curling is caused by the difference in the temperature and humidity by the depth of the slab in Jointed Plain Concrete Pavement. Slab curvature shape and size change due to curling exert a profound influence on the internal stress and roughness of the pavement, affecting structural and functional performance of the pavement. Direct measurement of the slab curvature entails many problems. Many measuring instruments have to be installed at the early-stage of the pavement construction, and the behavior of the slab curvature needs to be measured accurately from the early-stage. Moreover, the cost and technical difficulty are very formidable to measure the slab curvature. This study develops a measurement method for slab curvature in jointed concrete pavement at any given time by applying Power Spectrum Density Analysis and Inverse Fast Fourier Transformation to the profile data, that can be easily obtained at the construction field site. The effectiveness of this developed method is verified by measuring the profile data of the test road of jointed concrete pavement at an inland central expressway by the hour and by examining the result of extracting the slab curvature shape from this profile data. Additionally, the profile data of CRCP(Continuously Reinforced Concrete Pavement) sections on the same expressway were obtained and analyzed at the same time. The validity of the method developed for the slab curvature shape extraction is verified by comparing the result from the analysis of the profile data of CRCP sections with that from the analysis of the prof1Ie data of jointed concrete pavement sections.

• Journal of the Mineralogical Society of Korea
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• v.20 no.1 s.51
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• pp.1-6
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• 2007

Hectorite was synthesized by a two-step hydrothermal process from $Mg(OH)_{2}$, water glass (${\sim}30\;wt%\;SiO_{2}$) and Li-compound at $90{\pm}5^{\circ}C$. The product shows excellent dispersion and swelling properties. The mixture of the starting materials was heated in a glass vessel for the first reaction with continuous stirring and the pH of the solution was adjusted to $6{\sim}8$, resulting in the formation of a precursor of hectorite. The excess salt components were washed out from the resulting slurry and then was matured in the glass vessel for the 2nd reaction. Li compound was added during the reaction. After a 10 h retention, the gel of hectorite was formed. The XRD pattern of the synthesized one was coincided with that of natural hectorite and SEM study revealed uniform grains 50 m in diameter. The d001 basal spacing of the product moved from 12 to $17.4\;{\AA}$ after glycolation treatment. The measured value of CEC and the swelling capacity was 90 cmol/kg and $60{\sim}70\;mL/2\;g$, respectively.