• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2022년도 봄 학술논문 발표대회
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• pp.247-248
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• 2022

3D printer-based self-healing capsules have been proposed to heal cracks by enabling various structural designs, repeatable fabrication, and strength analysis of the capsules. The Fusion Deposition Modeling (FDM) method was used to design, analyze, and produce new self-healing capsules that are widely used at low cost. However, PLA extruded from FDM has low interlayer adhesion energy, and thus strength varies depending on the angle of load applied to the laminated layer and the concrete structure, thereby degrading the performance of the self-healing capsule. Therefore, in this paper, the structure of the capsule manufactured by the FDM PLA method has isotropic strength was designed. In addition, the fracture strength in the x, y, and z directions of the load applied through the compression test was analyzed. As a result, it was confirmed that the newly proposed capsule design has an isotropic fracture strength of 1400% in all directions compared to the existing spherical thin-film capsule.

• 한국패류학회지
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• 제30권2호
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• pp.139-153
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• 2014

We investigated fecundities in egg capsules and sizes at 50% of group sexual maturities in female Rapana venosa in three different salinity concentration regions (S-1, S-2, and S-3). In three different salinities, egg capsule heights, the number of egg capsules and the number of eggs and embryos were remarkably increased with the increase of female shell heights (or ages) and also increased with the increase of salinity concentrations. Heights of egg capsules, the number of egg capsules and fecundities (the number of eggs and embryos) were the maximum at S-1 (Gwangyang Bay (average 31.5 psu)) and the minimum at S-3 (the upper reaches of Seomjin River (average 15.5 psu)). Total numbers of fecundities of R. venosa $individual^{-1}year^{-1}$ were about $1{\times}10^6$ at S-1 region, about $8{\times}10^5$ at S-2 region, and about $2{\times}10^5$ at S-3 region. Rates (50%) of individuals reaching first sexual maturities in three different salinity regions (S-1, S-2 and S-3) were over 50% in females measuring 7.1-8.0 cm in shell height (considered to be two years old), and 100% in those > 10.1 cm (considered to be five years old). Biological minimum sizes ($RM_{50}$) in females in three different regions are 72.0 mm SH at S-1 region, 70.9 mm SH at S-2 region, and 74.6 mm SH at S-3 region, respectively. Exceptionally, smaller individuals (considered to be one year old) were participated in reproduction.

• Journal of Dairy Science and Biotechnology
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• 제24권1호
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• pp.53-63
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• 2006

Nano and micro capsulation (NM capsulation) involve the incorporation for nanofood materials, enzymes, cells or other materials in small capsules. Since Kim D. M. (2001) showed that a new type of food called firstly the name of nanofood, which means nanotechnology for food, and the encapsulated materials can be protected from moisture, heat or other extreme conditions, thus enhancing their stability and maintaining viability applications for this nanofood technique have increased in the food. NM capsules for nanofood is also utilized to mask odours or tastes. Various techniques are employed to form the capsules, including spray drying, spray chilling or spray cooling, extrusion coating, fluidized bed coating, liposome entrapment, coacervation, inclusion complexation, centrifugal extrusion and rotational suspension separation. Each of these techniques is discussed in this review. A wide variety of nanofood is NM capsulated - flavouring agents, acids, bases, artificial sweeteners, colourants, preservatives, leavening agents, antioxidants, agents with undesirable flavours, odours and nutrients, among others. The use of NM capsulation for sweeteners such as aspartame and flavors in chewing gum is well known. Fats, starches, dextrins, alginates, protein and lipid materials can be employed as encapsulating materials. Various methods exist to release the ingredients from the capsules. Release can be site-specific, stage-specific or signaled by changes in pH, temperature, irradiation or osmotic shock. NM capsulation for the nanofood, the most common method is by solvent-activated release. The addition of water to dry beverages or cake mixes is an example. Liposomes have been applied in cheese-making, and its use in the preparation of nanofood emulsions such as spreads, margarine and mayonnaise is a developing area. Most recent developments include the NM capsulation for nanofood in the areas of controlled release, carrier materials, preparation methods and sweetener immobilization. New markets are being developed and current research is underway to reduce the high production costs and lack of food-grade materials.

• 한국패류학회지
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• 제9권2호
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• pp.1-15
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• 1993

The reproductive ecology of the purple shell, Rapana venosa was investigated by the histological observations on depositions of the egg capsules, and hatching of larvae in the laboratory and the subtidal zone of the vicinity of piung-do, Chollabud-do, west coast of korea, for one year from June 1992 to May 1993. The results are summarized as follows:1. Rapana venosa is dioecious in sex. The ovary is composed of a number of ovarian lobules, and the testis comprises a number of ovarian lobules, and the testis comprises of gonads could be classified into 4 stages in males and 5 stages in females: 1) growing stage(in female subdivided into 2 stages of early and late growing stage). 2)mature stage. 3)spent stage or copulationstage. 4)rdcovering stage. The early growing stage in females of the purple shell was in September through February, late gorwing stage was in October to March, mature stage was in September to January, mature stage was in September to July, copulation stage was in Februaty to June and recovering stage in April to October.3. Spawning occurred 3-4 times at intervals of 1-3 days, and completed within 10 days from the beginning of spawning during the spawning season of the year.4. From the results of laboratory and field observations, egg masses are composed of a number of egg capsules, egg masses are occurred from May to late August, and in mid August depositions of egg mass in composed of 90-113 egg capsules, fecundity in an egg capsule was ranged 984 to 1,241 eggs(average 1,096 egg). Therefore, fecundity in total egg capsules spawned per individual during the spawning season is estimated as approximately 320,000 to 450,000 egges.5. The incubation period during deposition of an egg capsule to hatching larvad tood 17 days at 18.3-20.4%C(water temperature)and 1.021 (specific gravity fo sea water).

• 대한수의학회지
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• 제33권3호
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• pp.465-469
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• 1993

낭미충(Cysticercus cellutosae)에 자연감염된 돼지의 각 장기를 조직학적으로 검사하였던 바 다음과 같은 결과를 얻었다. 피막을 형성하는 낭미충은 골격근, 파하직, 심장 및 뇌조직에서 관찰되었다. 조직학적 소견으로는 골격근의 근막내와 심장 심외막하에서 낭충주위는 피막의 형성과 함께 급성 염증반응이 인정되었고 부위에 따라서는 교원섬유 및 선유아세포의 증식에 의한 두터운 피막이 관찰되었고 인접한 골격근 또는 심근과 견고하게 부착된 예도 있었다. 피막주위에서는 호산구, 임파구, 대식세포의 침윤이 부위에 따라 경미하거나 또는 심한 형태로 다양하였다. 대뇌의 연막하에 형성된 피막주위에는 혈관과 결합조직의 증식이 현저하였고, 혈관주위 원형세포의 침윤과 임파결절 모양의 구조가 인정되었다. GFAP 면역반응은 혈관주위를 따라 GFAP 양성의 섬유가 잘 발달되었고 피막낭 외측을 따라 전체를 둘러싸는 경항이었다. 결론적으로 유구낭미충 감염돼지의 조직소견은 감염 장기에 따라 염증반응이 다양하고 낭충의 피막은 감염 초기에 형성된 것으로 추정되었다.

• 산업기술연구
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• 제23권A호
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• pp.199-206
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• 2003

The charcoal-encapsulated methyl silica microcapsules were prepared by a O/W microemulsion sol-gel method, and the adsorption properties on aquatic humic acid were investigated. The capsules prepared were spherical, $100{\sim}1000{\mu}m$ in size. The size distribution was controllable by adjusting the size of charcoal powder, charcoal/methyl silica ratio, and agitating speed in O/W sol-gel process. Adsorption efficiency of charcoal for aquatic humic acid was decreased after encapsulation by methyl silica shell. The decreased adsorption efficiency can be dependent on the decrease of the BET surface area and pore volume after encapsulation. Diffusion properties of humic acid through the capsule shell also played an important role on adsorption efficiency. Therefore, the reasonable target pollutants for the capsules can be VOC or odor molecules which can overcome diffusion barrier through shell of capsules in air condition. Functionalization methods for the charcoal-encapsulated $CH_3(SiO)_n$ microcapsules by incorporation of $TiO_3$ as a phtocatalytic function and by incorporation of inorganic pigment as a color function were also investigated. $TiO_2$ coating properties were controllable by adjusting pH, temperature, and the concentration of $TiOSO_4$. In XRD measurement, the crystal form of the coated $TiO_2$ was anatase. For the colorization of the capsules, inorganic pigments were more efficient than organic dyes, and various color was introduced to the capsules using inorganic pigments.

• 한국건설순환자원학회논문집
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• 제8권4호
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• pp.475-482
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• 2020

본 연구에서는 결정성장형 자기치유 고상캡슐의 코어조성비에 따라 3수준의 고상캡슐을 제조하였으며, 결정성장형 자기치유 고상캡슐을 혼합하여 시멘트 모르타르를 제조하였다. 제조된 고상캡슐은 시멘트 질량의 3%와 혼합하여 시멘트 모르타르의 균열 유도 재령에 따른 치유 특성을 평가하였다. 결정성장형 자기치유 고상캡슐을 혼합한 시멘트 모르타르의 균열 유도 재령에 따른 균열치유 특성을 평가한 결과, 7일 재령 동안 반응하지 않은 수화물질이 남아있기 때문에 고상캡슐과 혼합된 시멘트 모르타르의 자기치유 성능은 28일 재령 대비 7일 재령이 증가한 것으로 나타났다.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2022년도 가을 학술논문 발표대회
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• pp.243-244
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• 2022

In this paper, experiments were conducted on signal amplification of polymer capsules for application to Ground Penetrating Radar so as to enable real-time monitoring of polymer capsules inside concrete using the Morphology Dependent Resonance phenomenon. A TEM CELL and a vector network analyzer were used to analyze the difference in resonance frequency depending on the material of the sphere and the presence or absence of fracture. In order to manufacture a capsule of a size that can be measured using millimeter waves used in GPR, we manufactured a capsule with a 3D printer and analyzed the effects of the presence or absence of coating and the size of the capsule on the resonance frequency. Resonant frequency or signal amplification is more affected by diameter than coating. The capsule showing the highest amplification is the resin-coated 50 mm diameter capsule with a 316-fold increase and the lowest capsule is the uncoated 10 mm diameter capsule with a signal amplification of 11.9 times. These results demonstrate the potential of GPR to measure the position and state of self-healing capsules, which are small-sized polymers, in real time using millimeter waves.

• 한국발생생물학회지:발생과생식
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• 제17권2호
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• pp.111-119
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• 2013

Golden hamsters reproduce in a limited time of a year. Their sexual activities are active in summer but inactive in winter during which day length does not exceed night time and environmental conditions are severe to them. The reproductive activities are determined by the length of light in a day (photoperiod). Melatonin is synthesized and secreted only at night time from the pineal gland. Duration of elevated melatonin is longer in winter than summer, resulting in gonadal regression. The present study aimed at the influences of continuous melatonin treatments impinging on the gonadal function in male golden hamsters. Animals received empty or melatonin-filled capsules for 10 weeks. They were divided into long photoperiod (LP) and short photoperiod (SP). All the animals maintained in LP (either empty or melatonin-filled capsules) showed large testes, implying that melatonin had no effects on testicular functions. Animals housed in SP displayed completely regressed testes. But animals kept in SP and implanted with melatonin capsules exhibited blockage of full regression by SP. These results suggest that constant release of melatonin prohibits the regressing influence of SP.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1997년도 춘계학술대회
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• pp.118-118
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• 1997

Solid dispersions were used to increase the dissolution rate of biphenyl dimethyl dicarboxylate (DDB) in water, with the ultimate goal of optimizing its bioavailability when incoporated into pharmaceuticals. Carriers used were Kollidon 30, Kollidon VA 64, 2-hydroxypropyl-${\beta}$-cyclodextrin (HPCD), sodium salicylate or sodium benzoate. DDB solid dispersions were prepared at drug to carrier proportions ranging from 1 : 5 to 1 : 20 (w/w) by solvent evaporation method. DDB tablets (7.5 mg) were prepared by compressing the powder mixture composed of solid dispersions, lactose, corn starch, crospovidone and magnesium stearate using a single-punch press. DDB capsules (7.5 mg) were prepared by filing the mixture into empty hard gelatin capsules (size #1). Dissolution studies of DDB from powdered solid dispersions, tablets and capsules were performed in 900 $m\ell$ of water at 100 rpm and 37$^{\circ}C$ by the paddle method. The dissolved amount was assayed by HPLC and expressed as the mean(%)of three determinations.