• 대한기계학회논문집 C: 기술과 교육
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• 제3권3호
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• pp.165-173
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• 2015

본 논문에서는 PRT(Personal Rapid Transit) 차량의 수직이송을 위한 장치를 개발하는 과정에서 수행된 주요 구조물의 정적 구조적 안전성 평가 결과를 다룬다. 지금까지 노선상에서 승객이 탑승한 상태에서 운영중인 차량의 수직이송에 대한 연구는 전무하며, 이는 기존의 2 차원 적인 교통운영 체계의 한계를 극복하는데 기여할 수 있을 것으로 기대된다. 특히, 본 연구에서 제안된 수직이송장치는 순환컨베이어 방식으로 연속 이송이 가능해서 통행량이 많은 지역에도 적용이 가능하다. 본 시스템이 물류분야에서 많이 사용되어 왔지만, 수직이동 시 차량의 무게에 의한 하중은 일반적인 물류의 수송과는 다르게 집중하중 형태로 컨베이어에 가해지기 때문에 이에 대한 구조적 안정성 평가는 필수적이다. 본 논문에서는 상용 유한요소 해석 프로그램인 $Ansys^{(R)}$를 이용해서 수직이송 장치의 기본 설계(안)의 구조적 안정성을 수치해석적 방법에 의해 평가하고자 한다.

• Asian-Australasian Journal of Animal Sciences
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• 제12권2호
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• pp.203-208
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• 1999

An 8 week feeding trial was conducted with 864 ISA Brown laying hens, 48 weeks old, to determine if microbial phytase $(Natuphos^{(R)})$ supplementation can reduce non-phytate phosphorus (NPP) level in laying diets. The experiment consisted of four dietary treatments: T1, control diet with 0.26% NPP (0.55% total P) wand no supplementary phytase; T2, 0.21% NPP (0.50% total P) diet with 250 U of phytase/kg of diet; T3, 0.16% NPP (0.45% total P) diet with 250 U of phytase/kg of diet; and T4, 0.11% NPP (0.40% total P) diet with 250 U of phytase/kg of diet. T3 showed the highest egg production and egg weight and the lowest feed conversion while T4 gave the lowest egg production and the highest feed conversion and mortality. Daily feed consumption ranged from 130.4 g (T4) to 132.7 g (T2). T1 and T2 were not significantly different in the production parameters. Eggshell strength, egg specific gravity, and eggshell thickness were not significantly different among treatments. However, broken egg ratio was significantly lower in T2 and T4 than in T1. Retentions of Ca, P, Mg, and Cu were greater in phytase supplemented treatments (T2, T3, and T4) than the control (T1), and those in T3 and T4 were greater than in T2. Excretions of P in phytase supplemented treatments (T2, T3, and T4) were significantly (p<0.05) smaller than in T1 but excretions of N were not significantly different among the treatments. Contents of ash in tibiae were not significantly affected by treatments, but contents of Ca, P, Mg, and Zn was increased and that of Cu decreased by phytase supplementation. It is concluded that the NPP concentration in the diet of Brown layers consuming about 130 g/d of feed can be safely lowered from 0.26% (0.55% total P) to 0.16% (0.45% total P). The excretion of P was reduced by the inclusion of 250 U phytase/kg of diet.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제15권3호
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• pp.199-210
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• 1993

Many surgeons are on the point of bone excision and reconstruction of the bone defects by autograft. xenograft, and allograft in the treatment of begin and malignant tumors of bone. Of all type of bone grafts, we received the autograft as the best ideal bone graft. Of autogenic bone graft, replantation of excised autogenic bone for reconstructiong the bone defects has been the ideal method until now, but early bone healing reponses and tumor cell devitalization after replantation of excised autogenic bone have not been identified for clinical applications. So, to evaluate bone healing response after replantation in rabbit's calvarial bone, we divided the experimental group into three groups. Group 1 is a fresh autogenous bone group. Group 2 is a deep frozen group. Group 3 is freeze-dried demineralized group. Obtained result were as followed: 1. Inflammatory cell infiltration appeared at I week and disappeared at 4 weeks in all experimental group, Especially, severe inflammatory cell infiltration showed in fresh autogenous bone group at 2 weeks. Group 3 is the least showing group on the point of inflammatory cell infiltration. 2. Osteoblastic activity evenly increased upto 4 weeks and maintained to 6 weeks and decreased after this period, especially osteoblastic activity in group 2 is less than group 1 and group 3. We can't discriminate between osteoblastic activity of group 1 and that of group 3. 3. In new bone formation, group 3 was more active than any other groups at early stage, but there were little differences among three experimental groups at later state. 4. Bone resorption around the grafted bone slightly appeared at 1 week and disappeared at 4 weeks in all experimental groups. We can find the more bone resorption in group 2 at 2 weeks than any other groups. We could suggest, as appears from our results, that freeze-dried deminiralized bone graft is the useful bone graft in the clinical applications of excised autogenic bone.

• Advances in Traditional Medicine
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• 제7권3호
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• pp.235-243
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• 2007

Anemarrhenae Rhizoma (AR) is used in traditional oriental medicine for various medicinal purposes. However, the exact mechanism that accounts for the anti-allergy and anti-inflammatory effects of the AR is still not fully understood. The aim of The present study is to elucidate whether and how AR modulates the allergic reactions in vivo, and inflammatory reaction in vitro. In this study, we showed that AR significantly decreased compound 48/80-induced systemic anaphylaxis, paw oedema, and histamine release from preparation of rat peritoneal mast cells. Also, AR inhibited the expression of inflammatory cytokine in PMA plus A23187-stimulated human mast cells (HMC-1). In addition, we showed that anti-inflammatory mechanism of AR is through suppression of nuclear factor-${\kappa}B$ activation $I{\kappa}B-{\alpha}$degradation. These results provided new insight into the pharmacological actions of AR as a potential molecule for therapy of inflammatory allergic diseases.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2017년도 춘계학술대회 논문집
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• pp.77-77
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• 2017

Titanium and its alloys offer attractive properties in a variety of applications. These are widely used for the field of biomedical implants because of its good biocompatibility and high corrosion resistance. Titanium anodizing is often used in the metal finishing of products, especially those can be used in the medical devices with dense oxide surface. Based on SAE/AMS (Society of Automotive Engineers/Aerospace Material Specification) 2488D, it has the specification for industrial titanium anodizing that have three different types of titanium anodization as following: Type I is used as a coating for elevated temperature forming; Type II is used as an anti-galling coating without additional lubrication or as a pre-treatment for improving adherence of film lubricants; Type III is used as a treatment to produce a spectrum of surface colours on titanium. In this study, we have focused on Type II anodization for the medical (dental and orthopedic) application, the anodized surface was modified with gray color under alkaline electrolyte. The surface characteristics were analyzed with Focused Ion Beam (FIB), Scanning Electron Microscopy (SEM), surface roughness, Vickers hardness, three point bending test, biocompatibility, and corrosion (potentiodynamic) test. The Ti-6Al-4V alloy was used for specimen, the anodizing procedure was conducted in alkaline solution (NaOH based, pH>13). Applied voltage was range between 20 V to 40 V until the ampere to be zero. As results, the surface characteristics of anodic oxide layer were analyzed with SEM, the dissecting layer was fabricated with FIB method prior to analyze surface. The surface roughness was measured by arithmetic mean deviation of the roughness profile (Ra). The Vickers hardness was obtained with Vickers hardness tester, indentation was repeated for 5 times on each sample, and the three point bending property was verified by yield load values. In order to determine the corrosion resistance for the corrosion rate, the potentiodynamic test was performed for each specimen. The biological safety assessment was analyzed by cytotoxic and pyrogen test. Through FIB feature of anodic surfaces, the thickness of oxide layer was 1.1 um. The surface roughness, Vickers hardness, bending yield, and corrosion resistance of the anodized specimen were shown higher value than those of non-treated specimen. Also we could verify that there was no significant issues from cytotoxicity and pyrogen test.

• 한국가금학회지
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• 제34권1호
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• pp.53-56
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• 2007

ME가와 단백질 수준이 백세미 육계의 생산성과 경제성에 미치는 영향을 알아보기 위하여 시중에 판매되는 육계 초이 및 전기 사료를 T1로 하여 전기(starter) 및 육성기(grower) 사료로 각각 이용하였고, T1 사료의 ME가와 조단백 함량을 하향 조정한 세 처리구 등 총 4가지 사료(전기: T1; ME 3,040, CP 21.40%, T2;ME 2,950, CP 20.62%, T3; ME 2,950, CP 19.90%, T4; ME 2,900, CP 18.50% 그리고 후기: T1; ME 3,070, CP 20.86%, T2; ME 3,000, CP 19.70%, T3; ME 3,000, CP 18.70%, T4; ME 2,920, CP 18.00%)를 실용 산란계 암컷(Hy-Line)과 육용 종계 수컷($Ross^{(R)}$)을 인공 수정하여 부화시킨 백세미 초생추 360수(4처리, 6반복, 반복당 15수)에 공시하여 5주간의 사양 시험을 실시하였다. 증체량은 T1구가 다른 세 처리구에 비해 가장 높았고 사료 섭취량 또한 T1구가 가장 높았다. 사료 전환율도 T1구가 가장 좋았다. 생산 지수에서도 T1이 153으로 T2: 112, T3: 108 그리고 T4: 101 보다 유의하게 높았다. 또한 경제성 분석에서도 T1이 다른 처리구에 비하여 현저하게 우수하였으며 kg 증체당 사료비가 가장 낮았다. 그 다음으로 T4, T3, T2 순이었다. 결론적으로 백세미의 증체량과 사료 요구율 및 경제성을 고려할 때 기존의 육계 사료를 급여 시 생산성이 가장 높았으며, 사료의 ME가와 조단백질 함량을 하향 조정할수록 생산성이 저하되었다.

• 디자인학연구
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• 제16권1호
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• pp.25-34
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• 2003

세계화시대에서 각 나라들은 자국의 고유한 이미지를 상징화시켜 다양한 디자인 개발을 하고 있다. 이는 타문화와의 차별화를 이용하여 부가가치 창출은 물론 국가 정체성과 이미지 제고 측면에서도 매우 중요하고 지속적인 발전이 이루어져야 한다. 우리나라를 대표하는 이미지는 무엇일까\ulcorner 태극기, 무궁화, 애국가, 김치, 한복, .등 많지만 본 연구에서는 한국의 태극기를 연상시킬 수 있고 시각적으로 강한 색상과 미적 요소를 지닌 태극무늬를 선택하였다. 태극무늬는 화합과 번영을 의미하여 예로부터 실생활의 소품이나 건축물 등에 많이 사용되어 왔다. 본 연구에서는 다양한 국제행사를 맞아 문화상품의 개발이 요구되는 시점에서 태극무늬를 현재 남북으로 분단되어 있는 우리의 현실에 적용하여 음양오행설에서의 음ㆍ양이 상극이지만, 상생과 서로 균형을 잘 이루어 상화로 이루어지듯이 남ㆍ북이 서로 대치국면이 아닌 서로 공생하고 화합하는 의미로서 태극무늬를 통일의 의미에 시각적으로 표현하여 엽서를 통해 통일을 앞당기고 세계에 우리의 바람을 알리고자 하는데 그 의의가 있다.

• Restorative Dentistry and Endodontics
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• 제18권2호
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• pp.291-316
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• 1993

Restorative procedures can lead to tooth fracture due to the relatively small amount of the remaining tooth structure. It is essential to prevent fractures by having a clear concept of the designs for cavity preparations. Among the several parameters in cavity designs, profound understanding of isthmus width factor would facilitate selection of the appropriate cavity preparation for a specific clinical situation. In this study, MO amalgam cavity were prepared on maxillary first premolar and filled with amalgam. Three dimensional, model with 1365 8-node brick elements was made by serial photographic method. In this model, isthmus was varied in width at 1/4, 1/3, 1/2 and 2/3 of intercuspal width and material properties were given for three element groups, i.e., enamel, dentin and amalgam. A load of 500 N was applied vertically on amalgam and enamel. In case of enamel loading, 2 model (with and without amalgam) was compared to consider the possibility of play at the interface between tooth material and amalgam. These models were analyzed with three dimensional finite element method. The results were as follows: 1. The stress was concentrated on the facio-pulpal line angle and distal marginal ridge of the cavity. 2. With the increase of the isthmus width, the stress spread around the facio-pulpal line angle and the area of stress concentration moved toward the proximal box. 3. In case of narrow isthmus width, the initiation point of crack would be in the area of isthmus corner of the cavity, and with the increase of the isthmus width, it would move toward the proximal box and at the same time the possibility of crack increase at the distal marginal ridge. 4. The direction of crack progressed outward and downward from the facio-pulpal line angle, and with the increase of the isthmus width, it approximated vertical direction. At the marginal ridge, it occurred in vertical direction. 5. It would be favorable to make the isthmus width narrower than a third of the intercuspal width, and to cover the cusp if isthmus width were wider than half of the intercuspal width. 6. It is necessary to apply the possibility of play to the finite element analysis.

• 대한한의학회지
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• 제16권2호
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• pp.44-61
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• 1995

Arranging 63 kinds of separate volumes and papers published on Oriental medicine, I could get the result as follows. 1. The herbs for internal application used commonly in vitiligo are 155 kinds totally. The herbs for external application are 67 kinds. The herbs for external and internal both application examined into 23 sorts. 2. Herbs for weakness syndrome in vitiligo are 49 kinds. Another type, excess syndrome is 105 sorts, the'latter is roughly twice as many as the former. 3. It is as follows that the results of study in relations to kinds, factors, and medical treatments of herbs about vitiligo in and out of the country with the division of former times to 1900, 1901 to 1980, 1981 to 1990, and 1991 to the latest day. In comparative study of inner and outer of thc country about factors and medical treatments of vitiligo in chronicle classification, its factors in the internal documents are classified by outside factors. Although there arc the differences of factors by each epoch, however, the factors of vitiligo according to external documents are blood stasis(血熱), deficiency of um of the liver and kidneys(肝腎陰虛), deficiency of blood(血虛), excess of exhaustion(勞倦過多) etc. Moreover, the medical treatment is more diverse and the differences by each epoch as to the medical treatment is also put down more saliantiy than in internal documents. 4. In comparison with herbs in experimental and no experimental documents, herbs applied for weakness syndromes in experimental method are 40 kinds totally. The herbs in no experimental methods are 35 kinds. The herbs used by experimental method are 65 kinds. The common herbs for excess syndrome by no experimental method are 78 kinds. We can see comparable difference from kinds of herbs used by experimental method. In brief, there are the differences classified by each epoch in Oriental medicine for treatment. Especially one of the most important feature, the frequency in use of weakness syndrome herbs has increased more than that of excess syndrome herbs. In external documents (china) and experimental study, generally the differences of common herbs and factors have disappeared through many experimentsitudy. The classification of its factors have been fractionalized clinically. Besides, in Western medicine and Orienal medicine, vitiligo tends to be prescribed not to simple skin disease but a mental and physical disease, a whole body and an internal disease.

• Restorative Dentistry and Endodontics
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• 제8권1호
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• pp.89-96
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• 1982

The purpose of this study is to identify the phases of four different types, low-copper lathe cut (Type II, class 1) and spherical (Type II, class 2) amalgam alloys which are made by Caulk company and high copper Dispersalloy (Type II, class 3) made by Johnson & Johnson and Tytin (Type I, class 2) made by S.S. White and to determine the Vickers hardness number on the individual phase and four different types of dental amalgam. After each amalgam alloy and Hg measured exactly by the balance was triturated by the mechanical amalgamator (De Trey), the triturated mass was inserted into the cylindrical metal mold which was 4 mm in diameter and 12mm in height and was pressed by the Instron Universal Testing machine (Model 1125) at the speed of 1mm/minute with 143$kg/cm^2$ according to the A.D.A. Specification No. 1. The Specimen removed from the mold, mounted and stored in the room temperature for 7 days. The speciman was polished with the emery paper from #220 to #1200 and finally on the polishing cloth with 0.3 and 0.05 um $Al_2O_3$ powder suspended in water. And then each specimen was etched by Allan's method and washed with Sodium Bisulfinite for 30 seconds. Finally differentiation and metallography on each phase were obtained by using metallographical microscope (Versamet, Union) and microhardness was obtained by using microhardness tester (MVH-2, Torsee). The results were as follows: 1. In the low-copper amalgam, the ${\gamma}$, ${\gamma}_1$ and ${\gamma}_2$ phase were observed and in the high-copper amalgam, the ${\gamma}$, ${\gamma}_1$. ${\epsilon}$ and ${\eta}$ phases were observed but ${\gamma}_2$ phase was not observed. 2. Among the microhardness of each amalgam phase measured under pressing a vickers diamond indenter with 2.0gm load for 30 seconds, e phase has the highest V.H.N (314 ${\pm}$ 20), and in low-copper amalgam 12 phase has the lowest V.H.N. (29${\pm}$1) and ${\eta}$ phase which was observed in high-copper amalgam has 230${\pm}$13 V.H.N and this phase is considerd to contribute to strengthen the handness in amalgam. 3. The V.H.N. measured under pressing a Vickers diamond indenter with 300.0gm load for 30 seconds in low-copper amalgam was lower than that of high-copper amalgam.