• Journal of Korea Foresty Energy
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• v.18 no.2
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• pp.78-83
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• 1999

This study was carried out to investigate the strength and techanical feasibility of laminated lumber from small-diametered Pinus densiflora. Small lumber is currently not used for structural laminated lumber sonstruction, but its properties may of elasticity(MOE). Twenty specimens were compared for each beam from laminae. The results showed that actual beam MOE values exceeded slightly the preducted values. Based on the evaluation and analysis of thirty six Pinus densiflora laminated beams, a bending strength of 673 kgf/$cm^{2}$, and MOE of 98,200 kgf/$cm^{2}$ were obtained. It was suggested that this small lumber may be a candidate for structural laminated beam construction to provide the proper combinations of laminae.

• Journal of architectural history
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• v.22 no.6
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• pp.23-34
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• 2013

The purpose of this study is to look into the weight-lightening phenomenon of the roof structure of some Hanok(韓屋), the Korean traditional houses found from the survey on the distribution and actual state of urban traditional houses existing in the whole region of Jung-gu, Daegu, Korea. As a result of judging from the pre-test of building registers for the research area, approximately 5,000 wood structure houses were found. A field data survey based on these findings showed that there are 1,752 Hanok houses. And the further classification of the Korean traditional houses by roof structure type shows that about 35% of them underwent weight lightening. While this kind of light-weight Hanok is different from the concept of traditional Hanok, they also show the survival method of Hanok that reflects the economical and technological phases of that period. It is expected that deeper understanding on the urban traditional houses will be possible through carrying out in-depth researches on techniques of the light-weight roof structure of the urban traditional houses that are supposed to have functioned as dwellings as commercial products.

• Journal of the Korean Wood Science and Technology
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• v.27 no.2
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• pp.78-86
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• 1999

The two parts of chestnut peels, outer and inner layers, were collected and investigated for cultivation of various mushrooms, i.e., Pleurotus ostreatus, Lentinus edodes, Hericium ramosum and the others. The inner layer of chestnut peels was contaminated with the mycelia of the blue fungi when collected, consisted of 17~20 % holocellulose, being a good material for growths of the above fungi. The outer layer was considered to be poor materials for fungal growth, because of lower amounts of minerals. Both mushrooms of Pleurotus ostreatus and Hericium ramosum grow well, and were produced fruiting bodies on the solid media containing only inner layers of chestnut peels. The Imhyup No.6 and Imhyup No.7 varieties of Lentinus edodes grow well, but produced few fruiting bodies in the solid media containing only inner layers of chestnut peels. The growth patterns of P. ostreatus and L. edodes were evaluated by production of $CO_2$. and considered to be different according to fungi. The inner layers of chestnut peels as agricultural by-products were considered to be a good material for mushroom cultivation, and outer layers could be used as being added with the other additives. The chestnut peels, being the environmental pollutants in rural areas, was considered to be a good substrate for mushroom cultivation.

• Journal of the Korean Wood Science and Technology
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• v.36 no.4
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• pp.26-36
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• 2008

As the height of the light-framed building increases, the lateral load and overturn-moment are increased and the possibility of the building overturn becomes larger. Because the shear wall resists lateral load in light-framed building, the reinforcement of shear wall is required. In order to reinforce the light-framed shear wall, using lag screw fastener type (B-HD) and using bolt type (S-HD) hold-down connectors were applied for test. And domestic larch lumbers, $38{\times}140mm$ and $89{\times}140mm$, KS 2nd grade, were used for the stud. The North American OSB panels were used for sheathing panel. Static loads, load speed 6 mm/min, were applied on top of the wall. As a result, shear strength of the wall that using hold-down connector was improved sufficiently. And when applying the S-HD type hold-down connector, stud should be reinforced against weakening by drilled hole. As increasing the number of lag screw, the number of bolt and the product allowable strength, the strength of shear wall that using hold-down connector was also increased. When applying hold-down connector to light-framed building using 38 mm stud, it must be reinforced by enlarging the thickness of stud like as 38 mm doubled column.

• Journal of the Korean Wood Science and Technology
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• v.15 no.4
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• pp.32-44
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• 1987

This study was carried out to analyze and furecast the domestic demand for plywood in Korea by regression models with time-series data for 16 years(1970-85). The results obtained were summarized as follows. 1. To analyze domestic demand for plywood, GNP, PWI and CWI were used as independant variables. The domestic demand equation was computed as follows: $^{in}DDP$=0.65186+1.29412 $^{in}GNP$-0.28385 $^{in}PWI$-1.05011 $^{in}CWI$ Where DDP : Domestic demand for plywood(1000 S/F) GNP: Gross national product (Billion won) PWI : Real wholesale price index of plywood CWI: Real wholesale price index of construction materials. 2. Among independant variables reflecting on the production activity of plywood industry, GNP was the most decisive in forecasting the domestic demand for plywood. 3. The significance can be recognized highly because the decision coefficient of the forecasting model which is obtained by using time series data is 0.9. 4. According to the estimated regression coefficients for GNP, PWI and CWI, GNP shows positive relation while PWI and CWI show negative relation. 5. An annual average increase rate of demand for plywood was 9.4 percent during expect period. Therefore, it was decreased slightly than that of 10.2 percent during sample period.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.3 no.2
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• pp.227-239
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• 1993

The author selected 77 dust emissing processes from 71 types of industries which placed in Sasang Industrial Complex in Pusan. The level of total dust was measured as areal concentration and personal exposure concentration by low volume air sampler and personal air sampler, respectively. Collected samples were classified into 5 groups (chemicals and rubber product, metal product, sawmills and wood, foundries and others). Respirable particulate and total dust of areal and personal exposure were analyzed. The results were as follows; 1. All of the respirable dust concentration and total dust of areal and personal concentration were log-normally distributed. 2. Geometric mean of respirable particulate of personal exposure concentration measured $0.55mg/m^3$ in the first group, $0.86mg/m^3$ in the second group, $0.39mg/m^3$ in the third group, $0.81mg/m^3$ in the forth group and $0.52mg/m^3$ in the fifith group. The exceed rates over TLV (thehold limit values) of total dust were 31.3% in the first group, 31.3% in the second group, 70% in the third group, 80% in the forth group and 13.3% in the fifth group. 3. There were singnificant difference between areal and personal exposure concentration and personal exposure concentration was higher than that of area. 4. In the case of high ratio of respirable particulate to total dust, pneumoconiosis incidence was high even though the workshop was opened and emissing dust concentration was low. These findings suggest that it is desirable to measure respirable particulate in environmental assessment of dust emissing workshops.

• Korean Journal of Organic Agriculture
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• v.15 no.4
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• pp.399-411
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• 2007

Korean organic farming has been well developed over the last two decades. It demonstrates that the number of certificated farm for organic agriculture and products have been drastically increased in recent year. However, the organic farmers have thought that organic farming rely only on organic fertilizer and they don't keep organic farming principle in which organic farmer should enhance biological activity and crop rotation. This study was to compare nutrient input, recommendation, cropping system and organic product circulation between the early $20^{th}$ century and beginning of the $21^{st}$ century. The population of Korea has increased 7.3 times more than that of a century ago but cultivated land has been decreased during 100 years. The rice production in 2002 was 4.2 times higher than that of production in 1912. The input of N, P and K in 1907 on the basis of King's suggestion was 95.6kg/ha, 15.9kg/ha and 3.0kg/ha, respectively. Nitrogen came from excreta (40%), green manure (55%) and compost (5%) in the early 20th century. On the other hand, organic farmer input organic resources such as wood chip (30.1%), compost (27.8%), rice straw (14%) and others (25%) these days. In terms of nutrient balance calculated nutrient and absorption by plants, organic rice farmer apply excessive nitrogen and phosphorus to the soil. They was used to put $7{\sim}10$ times more nitrogen than that of a century ago. Nutrient recommendation was similar in N and P between early 20th century and early $21^{st}$ century. Farmers in both century did not rotate crops in the field. Today, organic farmers engaged in more continuous cultivation than in early 20th century. Farmers in the early $20^{th}$ century produced locally, consumed locally the agricultural products, but organic farmers in the $21^{st}$ century produce the organic product in the local farmland and consumed in the large city and also a lot of foreign organic products have been imported in recent year.

• Archives of design research
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• v.16 no.1
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• pp.93-102
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• 2003

This thesis is a study for the standardization of the design of ginseng cultivating facility (also known as the sun off facility) for the improvement of farming environment. The core background of this study is to propose a basic study for introducing, for the first time, the modern ginseng cultivating facility that matches the position of korea as a main nation cultivating ginseng and to secure the production and quality value of Koryo Ginseng, which is a special world-level agricultural product of Korea, under the present WTO agricultural product open system. Right now, wood, rice straw, or vinyls, which are non-standardized or are for one-time use only are used. Therefore, as a concept of the design, 1 tried to revise the fact that these materials are being used to set up the facility repeatedly every year which is creating environmental pollution and wasting of our countries labor and resource. Concrete factors to be improved are as follows: First, standardization of the form and structure of mass production system; Second, introduction of new materials such as semi-permanent resin etc., for standardization of materials; 1 tried to make the above two factors into a shape based on a Korean image. As for the design, designed a standard unit model of the ginseng cultivation facility especially keeping in mind to design it so the facility can be freely connected and assembled according to the size and shape of the cultivation area.

• Natural Product Sciences
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• v.22 no.1
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• pp.60-63
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• 2016

The study is a pioneering effort to determine the mineral, nutritional, and phytochemical composition and phenolic content and to determine the free radical scavenging activity of Gigantochloa levis (Blanco) Merr, a native bamboo species (locally known as "bolo") in the Philippines. Proximate analysis showed that air-dried G. levis leaves contain 15.8% ash, 22.6% crude protein, 1.2% crude fat, 29.3% crude fiber, and 19.7% total sugar. Phytochemical tests indicated the presence of diterpenes, triterpenes, saponins, phenols, tannins, and flavonoids in both the ethanolic and aqueous leaf extracts, while phytosterols were only detected in the ethanolic extract. Folin-Ciocalteu assay determined the total phenolic content in gallic acid equivalents (GAE) to be $85.86{\pm}3.71$ and $32.32{\pm}1.01mg\;GAE/100g$ dried sample for the ethanolic and aqueous extracts, respectively. The total phenolic content in quercetin equivalents (QE) was $74.44{\pm}3.11$ and $29.43{\pm}0.85mg\;QE/100g$ dried sample for the ethanolic and aqueous extracts, respectively. The radical scavenging activity of the different solvent fractions containing varying concentrations of the extract was determined using the 2, 2-diphenyl-1-picrylhydrazyl (DPPH) assay. The ethyl acetate and 1-butanol fractions were found to have the highest radical scavenging activity. Mineral analysis via Energy Dispersive X-Ray Spectrometry (EDS) of the ash of G. levis leaves showed that Si is the major component, followed by K and Mg. These results point to the potential of G. levis leaves as a source of minerals and bioactive compounds with medicinal value.

• The Research Journal of the Costume Culture
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• v.23 no.1
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• pp.126-144
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• 2015

The object of this study is to develop textile designs and fashion products based on the cultural resource of Jeju Bangsatop, which means a stone tower preventing misfortune and driving out evil spirits. The field surveys of 32 Bangsatops located at 17 villages in Jeju were conducted. As a result, unlike stone towers located in other regions, Jeju Bangsatops made with basalt. In addition, wood and stone birds, Dolhareungbang, and other sculptures are built on the tops. Jeju Bangsatops were classified into four types based on the body form of the tops: Conical, truncated conical, trapezoid, and irregular shaped Bangsatops. Jeju Bangsatops located in a area or a village are symmetrically arranged in direction of south and north, left and right, east and west, or face to face. The conical, truncated conical, and irregular shaped Jeju Bangsatops which are designated as folk cultural properties or which have the unique sculptures of stone birds and the statues of Dolhareungbang built on the tops were selected as motifs for textile pattern design. The 4 basic patterns of Jeju Bangstops were designed. The six creative textile designs were developed by the various repeat arrangements of the basic patterns and were printed on oxford cotton fabrics by digital textile printing (DTP) method. The sixteen products of wallets, bags, hats and shoes were actually made with the DTP fabrics, the DTP fabrics which were naturally dyed in gray and blue colors, or the DTP fabrics which were redesigned with textile crayon. Therefore, it is confirmed that Jeju Bangsatop could be very useful as a motif for the development of cultural products focusing on Jeju tourism souvenir market.