• Composites Research
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• v.24 no.3
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• pp.1-5
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• 2011

Since the environmental problems and new stricter regulations are forcing the industries to introduce more ecological materials for their products, biodegradable materials have attracted increasing attention. Among these materials, Polylactic acid(PLA) is a promising candidate for its modulus, strength, chemical resistance. However, PLA could not be used for automobile industries for its low heat resistance and impact strength. In this study natural fibers were (jute fiber was) introduced as reinforcements in order to improve heat resistance and impact strength of PLA. Especially for improving the adhesion between PLA and jute, various surface treatments were tried. With each treatment, we verified that the impact strength of composite was improved. With annealing treatment, we found a remarkable increase of heat resistance of PLA composite.

• Journal of Educational Research in Mathematics
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• v.14 no.1
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• pp.111-127
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• 2004

In this note we examined some terms, parallel lines and angles in elementary school mathematics and middle school mathematics respectively. Since some terms are represented early in elementary school mathematics and not repeated after, some students are not easy to apply the terms to their lesson. Also, since the relation between parallel lines and angles are treated intuitively in 7-th grade, applying the relation for a proof in 8-th grade would be meaningless. For the variety of mathematics education, it is desirable that the relation between parallel lines and angles are treated as postulate. Also, for out standing students, it is desirable that we use deductive reasoning to prove the relation between parallel lines and angles as a theorem. In particular, the treatments of vertical angles and the relation between parallel lines and angles in 7-th grade text books must be reconsidered. Proof is very important in mathematics, and the deductive reasoning is necessary for proof. It would be efficient if some properties such as congruence of vertical angles and the relation between parallel lines and angles are dealt in 8-th grade for proof.

• Journal of Korean Medical classics
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• v.28 no.2
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• pp.33-45
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• 2015

Objectives : Through the study on Byeokyeoksinbang(辟疫神方), it would be expected to analyze Dokyeok(毒疫)'s characteristic and to comprehend how the changes in viewpoints of epidemic febrile disease were made. Methods : It has been done to analyze the original text of Byeokyeoksinbang(辟疫神方), and to compare the theory of Onbyeongjobyeon(溫病條辨) associated with the signature symptom of Dokyeok(毒疫). Results : Heo Jun(許浚) experienced a specific epidemic disease called 'Dokyeok(毒疫)', on which he made observations and analyzed its features and wrote Byeokyeoksinbang(辟疫神方). In Byeokyeoksinbang(辟疫神方), 'Dokyeok(毒疫)' is characterized by rash[疹], its pathogenesis is warm temperature, thus its treatment principle is removing interior and exterior heat. The book's pragmatic perspective is highly appreciated, as HeoJun improved and solidified existing medical knowledge up to date. In addition, Byeokyeoksinbang(辟疫神方) is significant in that it differentiated between macula[癍疹] and rash[疹], much earlier than the febrile disease school of the Qing dynasty. Conclusions : Between Byeokyeoksinbang(辟疫神方) and Onbyeongjobyeon(溫病條辨), there are differences in treatments and patterns of rash[疹]. Based on this, it will be able to compare each disease that is written in two books. And a study on comparing the development between epidemic febrile disease[瘟疫學] of the Joseon dynasty and febrile disease[溫病學] of the Qing dynasty will be carried out with a follow-up study.

• Journal of Powder Materials
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• v.25 no.4
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• pp.340-345
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• 2018

Additive manufacturing by electron beam melting is an affordable process for fabricating near net shaped parts of titanium and its alloys. 3D additive-manufactured parts have various kinds of voids, lack of fusion, etc., and they may affect crack initiation and propagation. Post process is necessary to eliminate or minimize these defects. Hot isostatic pressing (HIP) is the main method, which is expensive. The objective of this paper is to achieve an optimum and simple post heat treatment process without the HIP process. Various post heat treatments are conducted for the 3D-printed Ti-6Al-4V specimen below and above the beta transus temperature ($996^{\circ}C$). The as-fabricated EBM Ti-6Al-4V alloy has an ${\alpha}^{\prime}$-martensite structure and transforms into the ${\alpha}+{\beta}$ duplex phase during the post heat treatment. The fatigue strength of the as-fabricated specimen is 400 MPa. The post heat treatment at $1000^{\circ}C/30min/AC$ increases the fatigue strength to 420 MPa. By post heat treatment, the interior pore size and the pore volume fraction are reduced and this can increase the fatigue limit.

• Korean Journal of Soil Science and Fertilizer
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• v.31 no.1
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• pp.72-76
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• 1998

In order to investigate the emission pattern of sulphur dioxide gas from the soils in the plastic film house, the amounts of sulphur dioxide gas emitted from soils was periodically measured either in the plastic film house condition or in the incubator where the interior temperature was controlled to 10, 20. 30 and $40^{\circ}C$. Each soil was mixed with either mushroom, poultry, pig or fish meal compost at the rate of 0, 10, 20, 30, 40 and 50g/kg for individual treatment and then treated with addition of 50, 100, 150 and 200ml of water. A significant increase in the emission of sulphur dioxide gas was observed in the treatment of fish meal compost and such increase was initiated from the rate of l0g/kg, while little difference was observed in other treatments. Compared to upland soils, as control, the horticultural soils containing higher sulphur content emitted more sulphur dioxide. The emission of sulphur dioxide was favoured as temperature increased and was highest with the addition of 150ml of water.

• Journal of Sasang Constitutional Medicine
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• v.32 no.4
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• pp.29-44
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• 2020

Objectives We surveyed clinical status of Sasang Constitutional Medicine (SCM) for preparation of adaptation of Clinical Practice Guidelines for Sasang Constitutional Symptomatology. Methods We emailed Google survey form to Doctors of Korean Medicine registered the Association of Korean Medicine on 10/13/2020 and 10/21/2020 and closed survey 10/23/2020. We got a data of 654 cases, removed a case of error, analyzed data of 620 responses by frequency analysis Results and Conclusions Out of 620 respondents, 499 have answered that they refer to or make use of SCM. SCM is mainly applied in the field of treatments using Herbal Medicine. Doctors of Korean Medicine participated in survey of SCM, they think Diseases of digestive system are the most effectively treated by the methods of SCM. Sasang Constitutional Symptomatology most frequently observed are Soeumin Congestive Hyperpsychotic symptomatology, Soyangin Chest-Heat congested Symptomatology, Taeeumin Liver Heat-based Interior Heat disease. The diseases that are mainly applied by SCM are 'Diseases of digestive system' for Soeumin, 'Diseases of digestive system' for Soyangin, 'Diseases of respiratory system' for Taeeumin and 'not applicable' for Taeyangin. The important diagnostic methods of SCM are Inspection-listening and smelling examination-Inquiry-Palpation and survey. In the majority of cases, Prescription of Herbal medicine is used by adding or subtracting some herbal medicine from the original prescription suggested in the oriental medical classics and Saam acupuncture method is the most frequently used for the acupuncture therapy. Diet therapy is the most frequently used for the method of prevention and care.

• Korean Journal of Heritage: History & Science
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• v.53 no.4
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• pp.188-197
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• 2020

Termites play an important role as decomposers of the forest ecosystem, while simultaneously causing enormous damage to wooden structures. Currently, two species of subterranean termites have been reported in Korea, and termite damage to historical wooden buildings is occurring nationwide due to climate change, forest fertility, and the locational characteristics of historical wooden buildings. Subterranean termites make their nests underground or inside timber. Termites move underground and access wooden structures through the lower parts of the buildings, adjacent to the ground. Once termites attack the wooden structures, it not only spoils the authenticity of cultural heritage structure, but also hampers structural stability due to the decrease in the strength of the material. Therefore, it is important to prevent termite damage before it occurs. Chemical treatments are mainly used in Korea to control and prevent the damage. In foreign countries, physical barriers are also used to prevent entry to wooden buildings, along with chemical treatments. Physical barriers involve installing nets or particles that termites cannot pass through in the lower part of the building, around the pipes, and between the edges of the building or exterior walls and interior materials. Advantages of a physical barrier are that it is an eco-friendly method, maintains long-term effect after installation, and does not require the use of chemical treatments. Prior to applying physical barriers, studies into the characteristics of termite species must be undertaken. In this study, we evaluated the minimum passage size that each caste of Reticulitermes speratus kyushuensis can move through. We found that workers, soldiers, and secondary reproductive termites were able to pass through diameters of 0.7mm, 0.9mm, and 1.1mm respectively. Head height of termites was an important factor in determining the minimum passing size. Results from the current study will be used as a basis to design the mesh size for physical barriers to prevent damage by termites in historical wooden buildings in Korea.

• Journal of the Korean Institute of Landscape Architecture
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• v.40 no.5
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• pp.1-7
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• 2012

The main purpose of this research is to evaluate the effect of light quality on the growth and physiological activities of Laurus nobilis plants growing indoors, the L. nobilis seedlings were grown under four types of lighting for 180 days. The seedlings were grown under 4 different treatments((n=9 seedlings per treatment): control, control supplemental UV-B irradiated(+UV), FR reduced(-FR) and simultaneously supplemental UV-B irradiated and FR reduced(+UV-FR)). It was found that UV-B irradiation(+UV) reduced dry weight and leaf area, and increased leaf thickness and the amount of UV-absorbing compounds per unit leaf area. In contrast, a reduction in far-red(FR) light did not affect any of these parameters. Interestingly, however, the elongation growth and net photosynthetic rate of the L. nobilis seedlings grown under simultaneous UV-B irradiation and FR reduction(+UV-FR) were significantly decreased than the control treatment. From these results, it is concluded that the light quality has a large effect on the indoor growth of L. nobilis. This study can suggest basic information for managed in the L. nobilis in indoor using light quality.

• Korean Journal of Heritage: History & Science
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• v.39
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• pp.243-280
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• 2006

At the Bujang-ri Site, Seosan, South Chungcheong Province, around 220 archaeological features, including semi-subterranean houses and pits of Bronze Age and semi-subterranean houses, pits, and burials of Baekje period had been identified and investigated. In Particular, mound burials No. 5 of 13 of Baekje mound burials yielding a gilt-bronze cap along with other valuable artifacts drew international scholarly attention. The gilt-bronze cap from the mound burial No. 5 is a significant archaeological data not only in the study of Baekje archaeology but also in the study of international affairs and exchange at that time. At the time of exposure, the gilt-bronze cap was already broken into a number of pieces and seriously damaged by corrosion, and hardening and urethane foam were necessary in the process of collecting its pieces. Ahead of main conservational treatments on cap, X-ray photograph and CT(computerizes tomography) were taken in order to examine interior structure of the cap and to decide appropriate treatments. In the five layers identified in the profile of cap, a textile layer was set between a metal and a layerof bark of paper birch for avoiding direct contact of the metal and the bark of paper birch. Analyses were executed for examining textile layer and a layer of fibroid material. According to microscopic analysis, while the textile layer consisted of the simplest plain fabric with one fold among three kinds of textile structures, the layer of fibroid material was mixed with two or three kinds of fibers. A comparative analysis with standard sample using FT-IR (Fourier Transform Infrared Spectroscopy) announced that both textiles and fabrics were hemp. Analysis of kind of the paper birch resulted in barks of paper birch with 15 fold. A metallographic microscope, SEM, and WDS were used for the analysis of microscopic structures of plated metal pieces. While amalgam plating was treated as a plating method, the thickness of the plated layer, a barometer of plating technique, was ranged from $1.72{\mu}m$ to $8.67{\mu}m$. The degree of purity of gold (Au) used in plating was 98% in average, and less than 1% of silver (Ag) was included.

• Journal of agricultural medicine and community health
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• v.26 no.1
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• pp.19-35
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• 2001

This study was conducted to investigate the internal changes and the countermeasure for performance improvement by Separation of Prescribing and Dispensing Practice (SPDP) in Health Center. Data were collected from two sources: Performance report before and after SPDP of 25 Health Centers in Kyongsangbuk-do and 6 Health Centers in Daegu-City and self-administerd questionnaire survey of 221 officials at health center. The results of this study were summarized as follows: Twenty-four health centers(77.4%) of 31 health centers took convenience measures for medical treatment of citizens and convenience measures were getting map of pharmacy, improvement of health center interior, introduction of order communication system in order. After the SPDP in health centers, 19.4% of health centers increased doctors and 25.8% decreased pharmacists. 58.1% of health centers showed that number of medical treatments were decreased. 96.4%, 80.6% 80.6% 96.7% of health centers showed that number of prescriptions, total medical treatment expenses, amounts paid by the insureds and the expenses to purchase drugs, respectively, were decreased. More than fifty percent(54.2%) of health centers responded that the relative importance of health works increased compared to medical treatments after the SPDP, and number of patients decreased compared to those in before the SPDP. And there was a drastic reduction in number of prescriptions, total medical treatment expenses, amounts paid by insureds, the expenses to purchase drugs after the SPDP. Above fifty percent(57.6%) of officers at health center responded that the function of medical treatment should be reduced after the SPDP. Fields requested improvement in health centers were 'development of heath works contents'(62.4%), 'rearrangement of health center personnel'(51.6%), 'priority setting for health works'(48.4%), 'restructuring the organization'(36.2%), 'quality impro­vement for medical services'(32.1%), 'replaning the budgets'(23.1%) in order. And to better the image of health centers, health center officers replied that 'health information management'(60.7%), 'public relations for health center'(15.8%), 'kindness of health center officers'(15.3%) were necessary in order. Health center officers suggested that 'vaccination program', 'health promotion', 'maternal and children health', 'communicable disease management', 'community health planning' were relatively important works, in order, performed by health center after SPDP. In the future, medical services in health centers should be cut down with a momentum of the SPDP so that health centers might reestablish their functions and roles as public health organizations, but quality of medical services must be improved. Also health centers should pay attention to residents for improving health through 'vaccination program', 'health promotion', 'mother-children health', 'acute and chronic communicable disease management', 'community health planning', 'oral health', 'chronic degenerative disease management', etc. And there should be a differentiation of relative importance between health promotion services and medical treatment services by character of areas(metropolitan, city, county).