• The Journal of the Petrological Society of Korea
• /
• v.9 no.3
• /
• pp.142-168
• /
• 2000

The granites distributed in the Kyongsang basin contain the rocks which are different from the host rocks, and they are known as magic microgranular enclaves. The genesis of the magic micro-granular enclaves can be divided into four types: (1) rock fragments from country rocks; (2) cumulation of the early crystals in host magma or disruption of early chilled borders; (3) magma mingling; and (4) restite. These enclaves can be easily found in the granites around Mt. Wonhyo, Yangsan city. They are ellipsoidal in shape, and have phenocrysts might be originated from the host rocks and sharp contacts with the granites. Under the microscope, textures such as oscillation zoning, horn-blende-mantled quartz, rapakivi texture, and acicular apatite are observed, and these indicate that the enclaves were originated from magma and then produced by chilling. The evidences showing that the enclaves were formed by magma mingling are: (1) petrographical characteristics; (2) similarity of the compositions between the rim of plagioclase in the enclave and plagioclase in the granite; (3) linear trends of the major elements; (4) total REE content of the enclaves; and (5) Textural and compositional variations from rim to core in zoned enclaves. The magic end member of the enclave is regarded as the aphyric basaltic andesite in Mt. Sinbul-Youngchui area. The granites around Mt. Wonhyo experienced the magma mingling process which was produced by the injection of mafic magma at about 70 Ma, during the crystal differentiation, and then continued the crystallization. The equigranular granites and the micrographic granites in the study area are considered as the results after the magma mingling process.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.18 no.3
• /
• pp.307-315
• /
• 1989

This research was intended to know the influence of ${\omega}3\;and\;{\omega}6$ polyunsaturated fatty acids on rat's brain, kidney, testis tissues and composition of serum lipoprotein. Different kinds of diets containing perilla oil (PO) and red pepper oil (RPO) were administered to the rats: group 1, 10% PO; group 2, 7.5% PO and 2.5% RPO ; group 3, 5% PO and 5% RPO ; group 4, 2.5% PO and 7.5% RPO ; group 5, 10% RPO. The following are the results. 1. No significance of cholesterol concentration in brain was noticed among the groups, but group 5 was the highest and other groups tended to decrease. 2. As for concentration of triglyceride and phospholipid, the groups with more percentage of RPO increased gradually while those with more PO decreased by degrees. 3. No significance of cholesterol level in kidney was found among the groups. About triglyceride level, group 5 was the highest and it was relatively low in groups2, 3 and 4. group 5, however, was the lowest in phospholipid level. 4. As to cholesterol concentration in testis, groups 1 to 4 were low. About triglyceride level, group 1 increased while groups 2 to 4 decreased. 5. Concerning lipoprotein pattern in serum, HDL increased in groups 1 to 3, while LDL decreased gradually with the increase of perilla oil.

• Korean Journal of Food Science and Technology
• /
• v.7 no.4
• /
• pp.187-193
• /
• 1975

A supplemental effect of Undaria Pinnatifida extract on the composite flour prepared from a blend of wheat, barley, sweet potato, potato, and defatted soybean flours was studied in terms of binding properties, cooking test, and sensory analysis. Dry noodle of the composite flour was made by the conventional method and air dried. Instant noodle was prepared in a hot vegetable oil bath after the noodle was made. The standard was made of wheat flour only. 1. The noodle prepared with composite flour (wheat flour : barley flour, 5 : 5) and Undaria Pinnatifida extract (1 or 2%) showed same results of cooking and sensory tests as well as properties of texture as the standard. 2. The mixture of wheat, barley and defatted soybean flour (10%) had a less efficient binding capacity with Undaria Pinnatifida extract. The binding effect was, however, significantly improved with the wheat and barley flour mixture with either sweet potato or potato flour. 3. The instant noodle prepared with the composite flour (either barley, or sweet potato, or potato was mixed with wheat flour up to 70% separately) and hydroxypropyl methyl cellulose (1% as final) showed the higher oil absorption and the sensory results were the same as the standard. Nevertheless, the binding properties and cooking quality were less efficient.

• Journal of the Korean Society of Radiology
• /
• v.16 no.6
• /
• pp.799-805
• /
• 2022

Radiation therapy of human tissues, including bone tissue, is accompanied by side effects on normal tissues. It has a more lethal effect on stem cells, which play an essential role in tissue regeneration, including the basal cells constituting the tissue. In this study, the mouse parietal model, which implemented an artificial osteoradionecrosis model on the parietal region of the mouse, was artificially defected and then the bone regeneration was tested. In order to overcome the implemented osteoradionecrosis, a fibrin scaffold, widely used as a biomaterial, and stromal cell-derived factor-1 (SDF-1), which is used as a long-term treatment for damaged, were mixed to verify the osteoradionecrosis regeneration effect on the parietal of mouse. In order to expect a synergistic effect in the fibrin scaffolds, a fibrin scaffolds was prepared after maintaining the concentration of SDF-1 (1 ㎍/ml) in the fibrinogen solution. In this study, after artificially creating a osteoradionecrosis model in the parietal region of mouse, fibrin scaffolds were incorporated to analyze the effect of bone regeneration within 4 weeks, the initial stage of bone regeneration. In conclusion, the combined use of these two substances did not show a dramatic regenerative effect in inducing the regeneration of osteoradionecrosis in the parietal region of mouse. However, positive results were obtained that can be maintain the bone regeneration effect environment at the initial stage. Therefore, the combined use of the fibrin scaffold and SDF-1 is considered to be a suitable candidate for the effect of overcoming osteoradionecrosis.

• Journal of the Korean BIBLIA Society for library and Information Science
• /
• v.32 no.3
• /
• pp.285-304
• /
• 2021

The study has a purpose of understanding the factors that affect the oranizational commitment of the employees working in the libraries for visually impaired. To do this, the study chose personal background, emotional labor, role, job characteristics, organizational culture and organizational justice and attempted to find out how these factors affect the oranizational commitment. As a research method, mixed study method was used where quantitative analysis was complemented by qualitative analysis. For quantitative analysis, statistical analysis was conducted using the retrieved questionnaires. For qualitative analysis, the researcher had a one-on-one talk with the experts and employees who want to participate using an interview note was recomposed based on the survey responses. In the study results, emotional labor, job characteristics, organizational culture and organizational justice was proven to have influence on job engagement. To improve the job engagement, autonomy should be guaranteed by minimizing the organizational intervention to the assigned works and expanding the discretionary power. Furthermore, intensive management of the employees' emotional labor and fair process regarding the work performance is highly important.

• Proceedings of the Materials Research Society of Korea Conference
• /
• 2003.03a
• /
• pp.222-222
• /
• 2003

나노크기 금속입자가 분산된 세라믹 나노복합재료는 향상된 기계적 특성과 함께 독특한 전기적, 자기적 특성을 보여주어 새로운 기능성 재료로의 응용가능성을 갖고 있다. 그러나 소결 중의 반응이나 입자성장 등으로 형성된 반응상 또는 조대한 입자상이 세라믹 기지의 입계 등에 존재한다면, 나노크기 금속상 분산에 의한 기계적 특성의 향상과 독특한 기능성 부여라는 장점들이 없어지게 된다. 따라서 요구되는 특성을 구현할 수 있는 금속분산 나노복합재료의 제조를 위해서는 미세조직 제어를 위한 최적의 제조공정 확립과 미세조직과 특성 등의 관계에 대한 연구가 요구된다. 본 연구에서는 기지상으로 A1$_2$O$_3$를, 분산상으로는 저융점 금속이며 일반적인 A1$_2$O$_3$의 가압소결시에 (약 140$0^{\circ}C$) 액상으로 존재하는 금속 Cu를 선택하여 조성이 5 vol% Cu가 되도록 복합재료를 제조하였다. $Al_2$O$_3$와 CuO 원료분말들은 습식 및 건식 볼 밀링을 통하여 균일한 분말혼합체로 제조되었다. 혼합분말은 열간가압소결기 내에 장입한 후 35$0^{\circ}C$에서 30분 동안 H$_2$가스를 흘려주며 CuO를 Cu로 환원 처리하였다. 계속해서 H$_2$분위기를 유지하며 승온한 후, 각각 1000-145$0^{\circ}C$에서 분위기를 Ar 으로 치환하였다. 소결은 145$0^{\circ}C$에서 30 ㎫의 압력으로 1시간동안 행하였다 소결한 시편들은 직사각형 형태로 가공하였으며 표면은 0.5$\mu\textrm{m}$의 다이아몬드 입자로 연마하였다. XRD, SEM 및 TEM을 이용하여 상분석 및 미세조직관찰을 행하였다. 파괴강도는 3중점 굽힘 법으로 (3-point bending test) 측정하였다. 이때 시편 하부의 지지 점간의 거리는 30mm, cross-head 속도는 0.5 mm/min으로 하였고 5개의 시편을 측정하여 평균값을 구하였다.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.38 no.6
• /
• pp.629-636
• /
• 2014

For surface modification, bulk metallic glass coatings were fabricated using metallic glass powder and a mixture of a self-fluxing alloy or/and hard metal alloys with a heat-resisting property using a high velocity oxy-fuel coating thermal spraying process. Microstructural analyses and mechanical tests were carried out using X-ray diffraction, a scanning electron microscope, an atomic force microscope, a three-dimensional optical profiler, and nanoindenation. As a result, the monolithic metallic glass coating was found to consist of solid particle and lamellae regions that included many pores. Second phase-reinforced composite coatings with a self-fluxing alloy or/and hard metal alloy additives were employed with in-situ $Cr_2Ni_3$ precipitate or/and ex-situ WC particles in an amorphous matrix. The mechanical behaviors of the solid particles and lamella regions showed large hardness and elastic modulus differences. The mechanical properties of the particle regions in the metallic glass composite coatings were superior to those of the lamellae regions in the monolithic metallic glass coatings, but indicated similar trends in matrix region of all the coating layers.

• Journal of Dental Rehabilitation and Applied Science
• /
• v.28 no.3
• /
• pp.277-290
• /
• 2012

Dental implants are universal restorative method on edentulous site in oral cavity and generally recognized by patients as well as clinicians. Rapid bone resorption of labial portion of maxillary anterior area is performed due to dental trauma, chronic periodontitis, and so on. Accordingly, Implants on maxillary anterior alveolar ridge with narrow labiopalatal width would lead to bony defects of dehiscence or fenestration. In this case, guided bone regeneration procedure is used to augment maxillary anterior alveolar ridge. It can have mechanical and biological advantages to mix tissue adhesive with bone graft materials in guided bone regeneration procedure. In these cases, when the dehiscence or fenestration defects was occurred by dental implants on maxillary anterior alveolar ridge with narrow labiopalatal width, guided bone regeneration procedures were performed with various combination of particle bone graft materials(allograft, xenograft, and alloplast) mixed with fibrin glue, excepting autogerous bone. We reported that all of 4 cases showed favorable alveolar ridge augmentations.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.39 no.11
• /
• pp.1153-1159
• /
• 2015

Recently, synthetic biopolymers and bioceramics such as poly (${\varepsilon}$-caprolactone)(PCL), hydroxyapatite, tricalcium phosphate, biphasic calcium phosphate(BCP), and zirconia have been used as substrates to generate various tissues or organs in tissue engineering. Thus, the purpose of this study was the characterization of $ZrO_2$/BCP/PCL(ZBP) scaffold for bone tissue regeneration. Based on the result of single-line test, blended 3D ZBP scaffolds with fully interconnected pores and new complex pore pattern of $45^{\circ}+135^{\circ}$-type and staggered-type were successfully fabricated using a polymer deposition system. Furthermore, the effect of ZBP scaffold on mechanical property was analyzed. In addition, in vitro cell interaction of ZBP scaffold on MG63 cells was evaluated using a cell counting kit-8(CCK-8) assay.

• Proceedings of the Korean Nuclear Society Conference
• /
• 1998.05a
• /
• pp.46-51
• /
• 1998

토륨핵연료를 이용한 플루토늄 소모에 대한 연구를 목적으로 조직된 IAEA CRP(Coordinated Research Program) 업무의 일환으로, 농축우라늄 및 플루토늄을 seed로한 토륨핵연료를 국내의 900MWe 가압경수로에 이용하였을 경우에 플루토늄을 비롯한 heavy isotope의 원소량 변화, 사용 후 핵연료로부터의 방사능 준위, 노심의 반응도 특성을 분석하여 혼합핵연료 노심과 비교하였다. (Th+Pu)O$_2$,는 혼합핵연료 보다 플루토늄의 소모량이 약 2.4배 많으며, fissile 플루토늄 원소의 존재비율은 10% 정도 더 감소하는 것으로 나타나 플루토늄 소모의 특성이 유리하고 핵비확산 성격이 강한 것으로 나타났다 사용후 핵연료의 방사능은, 핵연료가 노심에서 바로 인출된 시점에서 는 (Th+Pu)O$_2$,가 가장 낮으나, 그 이후로는 (Th+Pu)O$_2$와 혼합핵연료의 방사능은 비슷한 반면, (Th+U)O$_2$,의 방사능이 가장 낮은 것으로 나타나 장기적으로는 (Th+U)O$_2$가 가장 유리하다. 대략적인 전환비는 (Th+Pu)O$_2$노심이 약 0.56, (Th+U)O$_2$ 노심은 약 0.63, 혼합핵연료 노심은 약 0.61 정도로 추정되었다. 토륨핵연료의 연소도에 따른 반응도 변화, 가돌리니아봉의 중성자 횹수 성질 및 반응도 특성 등 노심특성은 seed 물질의 특성과 함량에 따라 좌우되는 것으로 나타났다.