• Journal of the Korea Concrete Institute
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• v.28 no.4
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• pp.435-444
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• 2016

In Korea, approximately 48% of all households live in apartments, which are a form of multi-unit dwellings, and this figure increases up to 58%, when row houses and multiplex houses are included. As such, majority of the population reside in multi-unit dwellings where they are exposed to the problem of floor impact noise that can cause disputes and conflicts. Accordingly, this study was conducted to manufacture a high-weight, high-stiffness foamed concrete in order to develop a technology to reduce the floor impact noise. For the purpose of deriving the optimum mixing ratio for the foamed concrete that best reduces the floor impact noise, the amounts of the foaming agent, lightweight aggregate and binder were varied accordingly. Also, the target characteristics of the concrete to be developed included density of over $0.7t/m^3$, compressive strength of over $2.0N/mm^2$ and thermal conductivity of under 0.19 W/mK. The results of the experiment showed that the fluidity was very excellent at over 190 mm, regardless of the type and input amount of foaming agent and lightweight aggregate. The density and compressive strength measurements showed that the target density and compressive strength were satisfied in the specimen with 50% foam mixing ratio for foamed concrete and in all of the mixtures for the lightweight aggregate foamed concrete. In addition, the thermal conductivity measurements showed that the target thermal conductivity was satisfied in all of the foamed concrete specimens, except for VS50, in the 25% replacement ratio case for Type A aggregate, and all of the mixtures for Type B aggregate.

• Journal of Environmental Science International
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• v.17 no.3
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• pp.305-314
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• 2008

As forest land takes up 65% of the Korean peninsula, there have been continuing conflicts between the development and conservation of forest land. As the income level has changed over time, the usage of forest land in society has changed. There has been increasing demands for forest land for urban development and recreational use. On the other hand, a large proportion of the land is required to be preserved for the forest and the natural ecosystem in it. The existing management system for the forest land has been designed focusing on the management of the trees on the land, and not the land itself. Due to this limitation, the current management system of forest land has failed to protect the forest land from being developed indiscreetly, making it difficult to conserve and develop the forest land in an efficient way. A major question in forest land management is how to integrate economic use activities with the supporting ecosystems to maximize performance of the ecological-economic system. In order to promote sustainable use of forest resources, and to achieve efficient forest land management, it is prerequisite to evaluation on forest resources of natural ecosystems. Quantitative measures are needed that signify how necessary the services and products of forested ecosystems are to human endeavors. In this study, the natural wealth provided by forest land was quantified based on emergy synthesis. Emergy is a universal measure of real wealth of the work of nature and society made on a common basis. Thus, Calculations of emergy provide a basis for making choices about environment and economy following the general public policy to maximize real wealth. The goals of forest land management to achieve balance between the ecology and economy of its integrated system and to foster equity among the diverse outcomes of the forest land were assessed with emergy. Emergy was demonstrated to holistically integrated and quantify the interconnections of a coupled nature-human system allowing the goals of ecological balance and outcome equity to be measured quantitatively. Doing so will provide a better understanding of the basis of forest land wealth and the consequences of management decisions.

• Journal of the Korean Recycled Construction Resources Institute
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• v.3 no.1
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• pp.7-14
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• 2015

The aim of this research is suggesting dry processed bottom ash as a new and economical source of lightweight aggregate for mortar and concrete. The dry process of bottom ash is an advance method of water-free and no chloride because only cooled down by double dry conveyer belt systems. Furthermore, because of relatively slow cooling down process helps burning up the remaining carbon in bottom ash. Using this dry process bottom ash, to evaluate the feasibility of using as a lightweight aggregate for mortar and concrete, two-phase of experiments were conducted: 1) improving shape of the bottom ash, and 2) controlling grade of the bottom ash. From the first phase of experiment, additional abrasing process was conducted for round shape bottom ash, hence improved workability and compressive strength was achieved while unit weight was increased comparatively. Based on the better shape of bottom ash, from the second phase, various grades were adopted on cement mortar, standard grade showed the most favorable results on fresh and hardened properties. It is considered that the results of this research contribute on widening sustainable method of using bottom ash based on the dry process and increasing value of bottom ash as a lightweight aggregate for concrete.

• Korean journal of applied entomology
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• v.48 no.1
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• pp.87-94
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• 2009

KNI3126 which is the eco-friendly material made by plant extracts - neem and matrine - have been evaluated for efficacies against 6 main pests and toxicity on natural enemies. Insecticidal efficacies of KNI3126 against plant hopper were above 95% at 5 days after treatment (DAT), whereas pesticidal effects against the cotton aphid were above 95% at 3 DAT and slightly decreased at 5 DAT. Insecticidal efficacy against the palm thrips resulted in lower control value as 68.1% than that of chemical insecticides. KNI3126 showed more than 95% control value against diamond back moth, suggesting that it could suppress the population of pest hard to control as eco-friendly material. Mortalities against two-spotted spider mite were about 80% at 1 DAT and over 90% at 5 DAT, respectively. For evaluation of the toxicity on natural enemies, effect against predatory natural enemy was classified as moderate selective toxicity based on the criterion of International Organization of Bio-Control (IOBC), whereas against parasitic natural enemies was found to be relatively safe. Repellent effect was weak against plant hopper, but strong against two-spotted spider mite. In the toxicity test for safety, KNI3126 was classified as the lowest level at acute oral, acute dermal and fish toxicity test and did not induce the irritancy at skin irritation test and eye irritation test.

• Journal of Periodontal and Implant Science
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• v.25 no.3
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• pp.557-567
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• 1995

The purpose of this study was to investigated the effect of root planing and decalcified freeze dried allografts on the resorption of transplanted roots and the healing of preveously diseased recipient extraction sockets. The experimental chronic periodontitis was induced by elastic ligatures on the 2nd and 3rd mandibular premolars of 4 adult dogs, and after 8 weeks, crowns were removed and the teeth extracted. The extracted roots were split in half along the long-axis, and the extednt of plaque exposure was morked on the root surfaces with burs. The roots were either root-planed(Test group), or left uninstrumented(Control group), and transplanted in the extraction sockets with decalcified freeze-dried allografts filling the void. The flaps were sutured to cover the sockets completely. The animals were sacrificed after 12 weeks of healing, and the specimens were examined histologically. The results were as follows : 1. No signs of inflammation or disease activity were observed in either groups. 2. Replacement root resorption was observed in both groups. 3. More connective tissue attachments and less ankylosis were observed in the test groups compared to the control. 4. The unresorbed remains of DFDB particles were observed in both groups. 5. DFDB particles in the apical portion of the alveolar sockets were encased in newly-formed bone, while those in the coronal areas were seen encapsulated with connective tissue. 6. No significant difference was found between root-planed and uninstrumented roots relative to the healing and the bone fromation in the recipient extraction sockdets. From the present study, there seemed to be no significant benefits in root planing the transplanted roots or grafting the sockets with DFDB in order to curve the replacement resorption, although the root-planed roots showed more connective tissue attachments. There was also no significant benefits in root transplantation and DFDB for and enhanced healing and bone formation in alveolar extraction sockets.

• Tuberculosis and Respiratory Diseases
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• v.48 no.5
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• pp.699-708
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• 2000

Background : A presumptive histopathologic diagnosis of tuberculosis is commonly based on the finding of acid-fast bacilli upon microscopic examination of a diagnostic specimens. Although this traditional histochemical staining method is satisfactory, it is time-consuming and not species-specific. For more specific assessment, in situ hybridization assay with oligonucleotide probes is introduced. Methods : The human surgical specimens were obtained from tuberculosis patients, and experimental specimens were made by injecting cultured M. tuberculosis organisms into fresh rat liver. Oligonucleotide probes complementary to ribosomal RNA portion were synthesized and labeled with multiple biotin molecules. For a rapid detection, all procedures were carried out using manual capillary action technology on the Microprobe staining system. Results : The in situ hybridization assay produced a positive reaction in experimental specimens (80-90% sensitivity) after pepsin-HCl pre-treatment for a good permeabilization of probes, but reliable result was not obtained from human surgical specimens. Conclusion : It is, therefore, suggested that biotin-labeled oligonucleotide probes have considerable potential for identification and in situ detection of M. tuberculosis but, there are some barriers to overcome for the diagnostic use of this method.

• Journal of Music and Human Behavior
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• v.17 no.1
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• pp.1-24
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• 2020

The internship is essential for the music therapy curriculum and affords interns the opportunity to apply their classroom-based knowledge and skills to real-world clinical settings. However, challenges associated with the internship can result in interns undergoing trial-and-error learning, interpersonal conflicts, and intrapersonal difficulties. An experiential music therapy group may be useful in helping interns process these incidents and develop their personal and professional skills. We explored the experiences of music therapy interns participating in therapeutic song writing. In this study, five music interns completed two 4-hour sessions of therapeutic song writing. Following the second session, a group interview was conducted with participants to gather data on their experiences. The interview was recorded, transcribed, and analyzed. Six themes and 18 sub-themes were derived from the data. The six themes were preconceptions of therapeutic song writing, meaningful lyric creation, challenges in song composition, structured experiences during song writing process, development of self-awareness through music, and relational experiences resulting from the group process. Participants were able to incorporate their individual internship experiences into a single song by communicating with group members during the step-by-step process. Participation in therapeutic song writing was found to help music therapy interns identify and process challenges encountered during their internship and further their personal and professional development.

• Atmosphere
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• v.23 no.4
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• pp.389-400
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• 2013

Chugugi and Wootaeck rainfall data of Gyeonggi Province from 1830 to 1893 were restored from the "Gaksadeungnok" that is the government records between the central government and the local during the Joseon Dynasty. The restored data periods were 27, 10, 9 and 14 years for Kwangju, Suwon, Ganghwa and Gaeseong, and the total number of restored data was 655 for the Chugugi and 427 for the Wootaek, respectively. The variation pattern of monthly rainfall by Chugugi was investigated and it showed that the monthly rainfall more than 300 mm was recorded 25 times with 18 times in July, 5 times in August and 3 times in June. The cases of more than 500 mm were also recorded 8 times with the maximum 787 mm at the Kwangju in July 1862, showing the similar pattern to Seoul. The monthly mean rainfall for the Gyeonggi Province were 259 mm in July, 204 mm in August and 121 mm in June, which were about one third of that of Seoul. The correlation analysis between the Chugugi and Wootaek data was carried out to derive the quantitative values of Wootaek observations. It revealed that 1 'Ri' of Wootaek observation was equal to approximately 1 'Chon (Chugugi unit)' or 20 mm, while 1 'Seo' was very variable between 2 and 6 'Boon (Chugugi unit)' with the median value approximately 3 'Boon' or 6 mm. Recalculated Wootaek data showed that the monthly rainfall in July, August, and June were 289 mm, 154 mm, and 124 mm, respectively. Through this study, some features of the rainfall variation pattern during 1830~1893 were figured out, and quantitative interpretation of Wootaek data became possible based on the restored rainfall data from the "Gaksadeungnok". Though many pages of the book have been lost during the last hundreds years, "Gaksadeungnok" is still very meaningful and of practical use, for it contains plenty of the local data throughout the whole country during the latter part of Joseon Dynasty. Therefore, further studies are strongly recommended on the restoration of climate related data and on the climatic tendency of 19th century of Korean peninsular.

• Korean Journal of Biological Psychiatry
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• v.5 no.1
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• pp.107-113
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• 1998

Objectives : To evaluate the relation of onset-age and plasma level of ${\beta}$-endorphin, Ethanol, ${\beta}$-endorphin, cortisol and blood glucose were compared in 48 male alcoholics and 29 normal controls Methods : Alcoholics are divided into two groups by onset-age of alcoholism. Blood samples were obtained before and after 0.75gm/kg of ethanol consumption at the 7th admission day. Results : 1) The ratio of onset-age before 25 years to after 25 years of the patient group was 2 to 3. 2) There was no significant difference in age at admission between two patient groups. 3) There was no significant difference in change of plasma ethanol levels among three groups. 4) There was no significant difference in change of plasma ${\beta}$-endorphin levels among three groups. 5) There was no significant difference in change of plasma cortisol level among three groups. 6) There was no significant difference in change of fasting blood sugar level among two patient groups.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.4
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• pp.1479-1487
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• 2013

The river levee collapse and flood damages are dramatically increased due to the floods which caused by abnormal weather nowadays. The counterplan like TDR(Time Domain Reflectometry) river levee leaking exploration technique is needed to that levee failure causes of levee failure such as levee failure by penetration, piping, inadequate levee materials selection, poor compaction are almost 52% of the failure. This research practiced various comparing experiments of existing TDR(probe and tube types) and developing CAP type TDR to evaluate acrylic small CAP mould and low-cost TDR levee leaking monitoring system which was used probe type TDR. As the result, evaluated TDR system had 20cm critical exploration performance which was a leaking exploration performance, The functional ratio of TDR exploration sensitivity of dry density was sensitive more than 3 times than dry density, and weathered granite soil foundation water contents(w)-dielectric constant(${\epsilon}$) corelation formula was suggested to measure functional ratio on developing cap type TDR system.