• Journal of the Korean Wood Science and Technology
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• v.39 no.2
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• pp.140-147
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• 2011

The strength properties of wooden retaining wall which was made with pitch pine were evaluated. Wooden retaining wall was made with diameter 90 mm of pitch pine round posts treated with CUAZ-2 (Copper Azole). The length of the front stretcher of the retaining wall was 3,000 mm. The distance between the headers (the notched member) is 1,000 mm in center and is 900 mm in side. There were connections every 2,000 mm because actually the length of stretcher is limited in the retaining wall. The strength test was carried out according to connection type because the section between stretchers can act as a defect. A result of the strength test according to connection type confirms that connection does not act as defect because the strength of retaining wall in single stretcher is similar to that in the section between stretchers. The strength test of the wooden retaining wall was carried out in 5 types according to the condition of the base section. When the upper soil pressure was 9.8 kN/$m^2$, the maximum load of the retaining wall fixing the front foundation shows higher values than those of others. But the total deformation is lower in the retaining wall not to fix a base section than in that to fix a base section. It is thought that the retaining wall not to fix a base section shows low value because the deformation is distributed throughout the retaining wall and it is confirmed that the soil pressure affects supporting the structure because the deformation of the retaining wall under low pressure is 3~4 fold higher than those of others. The failure mode of the retaining wall is the overturning type because the high section is deformed. Mostly, the failure mode is the separation of the header in the notched section.

• KIEAE Journal
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• v.14 no.4
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• pp.19-26
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• 2014

The building section is providing immediate causes for global climate change problems since it takes about 50% of carbon emission, 20~50% of waste discharge, 33% of energy consumption, 40% of resource use, and 17% of water consumption. So, many countries over the world have developed and implemented green building certification systems to assess sustainable performances of buildings since the early 1990s. In korea, the green building certification system to induce the diffusion of sustainable buildings was first introduced in 2002 and developed as an improved version of the G-SEED(Green Standard for Energy and Environmental Design) system in 2013 after major revisions of related legislations. This research conducts a survey targeting residents on an apartment building that was certified as green building and examines the importance of assessment criteria on apartment buildings to certify green buildings using the Analytic Hierarchy Process(AHP) method. And it proposes a new direction on certification assessment standards from the resident's prospective. As a result, assessment criteria such as indoor environment, ecological environment, energy & environment pollution, and maintenance management among 7 main ones turned out important on assessing the G-SEED system for apartment buildings, while criteria such as material & resource, water circulation management, and land use & transportation did relatively unimportant.

• Natural Product Sciences
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• v.5 no.1
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• pp.39-47
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• 1999

The flowers of Alcea rosea L., Malvaceae, sold in the Indian market under the trade name 'Gulkhairo', are well known for their expectorant, cooling and diuretic properties and used in many indigenous cough mixtures in India. The present paper deals with the detailed pharmacognosy of the floral parts including morphological, anatomical, phytochemical and fluorescence characters. Some of the diagnostic features of the drug are : pedicel characterized by multicellular appendages, stellate hairs, rosette crystals of Ca-oxalate, starch sheath and large sized mucilage canals; sepals having distinctive multicellular appendages arranged in a semilunar fashion present adaxially at their base; monadelphous stamens, pollen grains pentaporate provided with dimorphic spines; placentation axile, ovules campylotropous; dark green fluorescence of the powder with nitrocellulose in amyl acetate and yellow fluorescence of trichomes under Fluorescence microscope.

• International Journal of Advanced Culture Technology
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• v.8 no.2
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• pp.159-164
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• 2020

The response analysis of frame structure with open section beams considering warping conditions and short duration load have been performed. When a beam of frame structure is subjected under torsional moment, the cross section will deform a warping as well as twist. For some thin-walled sections warping will be large, and accompanying warping restraint will induce axial and shear stresses and reduce the twist of beam which stiffens the beam in torsion. Because of impact or blast loads, the wave propagation effects become increasingly important as load duration decreases. This paper presents that a warping restraint in finite element model effects the behavior of beam deformation, dynamic mode shape and response analysis. The computer modelling of frame is discussed in linear beam element model and linear thin shell element model, also presents a correlation between computer predicted and actual experimental results for static deflection, natural frequencies and mode shapes of frame. A method to estimate the number of normal modes that are important is discussed.

• Bulletin of the Korean Mathematical Society
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• v.49 no.5
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• pp.1015-1025
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• 2012

Let $[n]=\{1,2,{\cdots},n\}$, and let $PO_n$ be the partial order-preserving transformation semigroup on [n]. Let $$CPO_n=\{{\alpha}{\in}PO_n:({\forall}x,y{\in}dom{\alpha}),\;|x{\alpha}-y{\alpha}|{\leq}|x-y|\}$$ Then $CPO_n$ is a subsemigroup of $PO_n$. In this paper, we characterize Green's relations and the regularity of elements for $CPO_n$.

• Journal of Korean Society of Rural Planning
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• v.18 no.3
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• pp.13-24
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• 2012

This study aimed to investigate the images that affect general travel behavior and satisfaction of eco-tourists of Section seven of Jeju Olle-gil and to give eco-tourists preferred images to newly constructed eco-tour sections. Adjectives were selected to evaluate images, and for analysis, a survey was carried out with 132 persons who have toured 7 section of Jeju Olle-gil. On this survey, basic travel type, overall satisfaction, image before and after experience, age, gender, satisfaction level and accompanying type were inquired. 81(61.4%) knew section 7 of Jeju Olle-gil 'in advance', and 58(39.1%), which takes up the largest portion in this question, came to choose section 7 by a word of mouth. 95(71.9%) answered that they stayed 2 nights and 3 days, and 55(41.7%) answered that they stayed at a pension as accommodation. As for accompanying type, 34(25.7%) answered they accompanied family and relatives. As for the decision of visit, 60(45.5%) replied that they decided one month prior to the visit. And as for the purpose of visit, 63 (33.8%) replied they visited to appreciate nature. The adjectives that demonstrate overall satisfaction and significance level of the tourists were 'placid', 'refreshing', 'living', 'mountainous' and 'green'. As for the satisfaction level, people were satisfied with its environment, cleanliness level and direction boards. The types of section preferred by the tourists were clay pavements, followed by sand-masa soil mixture pavement and wooden deck pavement. 'Oidolgae' section was selected as the representative section, and 10:00a.m.~12:00p.m. was preferred as visiting time. And it is also proved that people were positive in appointing photo zones.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.20 no.2
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• pp.1-14
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• 2021

The exclusive bus lanes in the Yeongdong Expressway were implemented in the Singal to Yeoju section in 2017, but the capacity of both exclusive bus lanes and general-purpose lanes of the Yeongdong Expressway decreased and the travel time increased, reducing it to the Singal to Deokpyeong section. Therefore, it is necessary to increase the efficiency of exclusive bus lanes to revitalize public transportation and improve environmental problems. This study calculated the willingness to pay and the social benefits of permission for Green cars to drive on exclusive bus lanes in Yeongdong Expressway. A survey was conducted on two groups of Green car users and Expressway users, and the willingness to pay was estimated using the CVM method. As a result, the average WTP of Green car users were estimated to be 218.7(won/km·person), and that of Expressway users were estimated to be approximately 235.5(won/km·person). The direct benefits were estimated to be approximately 7.9 billion won for Green car users, and 8.5 billion won for Expressway users in 2019. Finally, the value of time saving was estimated to be approximately 8.0 billion won.

• Journal of the Korean Wood Science and Technology
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• v.44 no.4
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• pp.539-550
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• 2016

The objective of this research was to evaluate physical and mechanical properties of three species of Styrax woods from North Tapanuli in Indonesia. The woods were more than 15 years old. Physical properties such as specific gravity, green moisture content, and volume shrinkage were determined by the procedures based on BS-373 standard for small clear specimen. Furthermore, mechanical properties, including modulus of rupture, modulus of elasticity, compression parallel to grain and hardness were also tested according to the standard. Along the stem direction, the edge section had better properties compared with those near the pith section. And the base section had also better properties than upper section. Based on the specific gravity, all of the Styrax woods in this research were classified into III-IV strength classes. A good dimensional stability was demonstrated by the value of the tangential and radial ratio which reached one. With the consideration of the mechanical properties, Styrax woods were suitable use for raw materials of light construction, furniture and handy craft.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.37 no.3
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• pp.304-308
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• 2024

In this paper, in order to analyze the PMU data of the accident section, we collected the raw data of a total of 35 PMU installed at the Yeonggwang substation and tried to find a way to analyze the data, and analyzed the data using Excel format and formula. As a result, the three-phase voltage and current data of the PMU were calculated using formulas in Excel and interpreted as effective and reactive power, and it was possible to check the effective and reactive power of the accident section through the graph to see why it was different from before the accident. As a result, it was confirmed that each power was greatly reduced in the graph of the effective and reactive power of the accident section, and it was confirmed that the loss occurred as the power of the accident section was greatly reduced.

• Corrosion Science and Technology
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• v.21 no.4
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• pp.273-281
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• 2022

The effect of addition of Cu on the localized corrosion performance of aged duplex stainless steel in chloride media has yet to be explained in a consistent manner, and there is some controversy in the literature regarding the composition of stainless steel and the experimental conditions (pH, temperature, chloride concentration, etc.) used. In this work, the effect of the addition of Cu on the microstructure, hardness, and corrosion resistance of duplex stainless steel in an acidic chloride or high concentration sulfuric acid solutions was investigated for annealed and aged alloys. The Cu addition of annealed duplex stainless steel strengthened the alloy and reduced the ferrite contents of the alloy, and it also increased the polarization behavior in chloride or sulfuric solutions, except for the case of a high potential in acidic chloride solution. However, the Cu addition of aged duplex stainless steel reduced the formation of harmful phases such as sigma and kai and increased the polarization behavior in acidic chloride or sulfuric solutions up to 0.8 wt% of the Cu content, after which it slightly decreased at 0.8 wt% Cu or more.