• 제목/요약/키워드: rug

검색결과 34건 처리시간 0.034초

A numerical study on hydrodynamic maneuvering derivatives for heave-pitch coupling motion of a ray-type underwater glider

  • Lee, Sungook;Choi, Hyeung-Sik;Kim, Joon-Young;Paik, Kwang-Jun
    • International Journal of Naval Architecture and Ocean Engineering
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    • 제12권1호
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    • pp.892-901
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    • 2020
  • We used a numerical method to estimate the hydrodynamic maneuvering derivatives for the heave-pitch coupling motion of an underwater glider. It is very important to assess the hydrodynamic maneuvering characteristics of a specific hull form of an underwater glider in the initial design stages. Although model tests are the best way to obtain the derivatives, numerical methods such as the Reynolds-averaged Navier-Stokes (RANS) method are used to save time and cost. The RANS method is widely used to estimate the maneuvering performance of surface-piercing marine vehicles, such as tankers and container ships. However, it is rarely applied to evaluate the maneuvering performance of underwater vehicles such as gliders. This paper presents numerical studies for typical experiments such as static drift and Planar Motion Mechanism (PMM) to estimate the hydrodynamic maneuvering derivatives for a Ray-type Underwater Glider (RUG). A validation study was first performed on a manta-type Unmanned Undersea Vehicle (UUV), and the Computational Fluid Dynamics (CFD) results were compared with a model test that was conducted at the Circular Water Channel (CWC) in Korea Maritime and Ocean University. Two different RANS solvers were used (Star-CCM+ and OpenFOAM), and the results were compared. The RUG's derivatives with both static drift and dynamic PMM (pure heave and pure pitch) are presented.

세파졸린피발로일옥시메칠에스텔의 합성 및 생물약제학적 연구 (Synthesis and Biopharmaceutical Studies of Cefazolin Pivaloyloxymethyl Ester, A Novel Prod rug of Cefazolin)

  • 안선엽;이진환;최준식;범진필
    • Journal of Pharmaceutical Investigation
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    • 제22권2호
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    • pp.139-148
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    • 1992
  • A prodrug of cefazolin pivaloyloxymethyl ester (CFZ-PV) was synthesized to improve oral absorption and bioavailability of parent drug by esterification of sodium cefazolin (CFZ) with chloromethyl pivalate. The successful synthesis of CFZ-PV was confirmed by spectroscopic analysis. Partition coefficient studies showed that CFZ-PV is more lipophilic than CFZ. The pharmacokinetic characteristics of CFZ-PV and CFZ preparations were compared following oral administrations of these compounds to rabbits. The analysis of CFZ in plasma was conducted by HPLC method. The ester compound (prod rug) was not detected in plasma following oral administration of CFZ-PV, and although CFZ-PV had not microbiological activity in vitro, the plasma taken after CFZ-PV administration had microbiological activity. From above observations, it was noted that CFZ-PV is rapidly hydrolyzed to CFZ in the body. And it was found that the oral absorption of CFZ-PV was increased, yielding 2-fold higher bioavailability than CFZ. From the results of this experiment, it was concluded that CFZ-PV could be a novel prodrug of CFZ which can improve the oral bioavailability of CFZ.

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NFT 거래에 따른 사기범죄 유형 분석에 관한 연구 (A Study on the Analysis of Fraud Crime Types according to NFT Transactions)

  • 송혜진
    • 한국재난정보학회 논문집
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    • 제19권4호
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    • pp.908-915
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    • 2023
  • 연구목적: 본 연구의 목적은 NFT 거래시 일어나고 있는 여러 가지 범죄들 중 사기범죄 유형을 살펴보고, 이에 대한 범죄유형 분석과 단속 방법 및 법적 한계로 인한 제도적 문제에 대해 접근해보고자 하기 위함이다. 연구방법: NFT 거래시 나타나는 사기범죄 유형을 분류하기 위해 선행연구 조사결과와 현재 발생하고 있는 사건사례 등을 통하여 범죄유형을 분석하였다. 연구결과: NFT를 통해 내 일어나고 있는 범죄는 대부분 러그풀, 도난사건, 개인정보 탈취사기, 돼지도살 등 여러 가지 사기범죄 유형들이 나타나고 있다. 따라서 이 유형들을 분류하였고 다양한 피해사례도 분석하였다. 저작권의 문제이다. 결론: 현재 전세계적으로 NFT의 사기범죄 발생으로 생기는 금적적 문제가 가장 우려되고 있으며 향후 시장이 커지면서 그 규모는 더욱 방대해질 것이다. 따라서 우리나라에서도 범죄예방 및 수사와 검거활동에 영향을 줄 수 있는 범죄유형 분석을 통해 다양한 제도적 보완과 정책이 마련되어야 할 것이다.

국제거래(國際去來)에서 전자계약(電子契約) 성립(成立)의 장애요인(障碍要因)에 관한 연구(硏究) (A Study on the Obstacles of international Contract in Electronic Commerce)

  • 서백현
    • 통상정보연구
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    • 제5권2호
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    • pp.207-225
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    • 2003
  • The purpose of this study is to examine the legal aspects on the formation of international contract in electronic commerce. The findings could be summarized as follows. rug, the contract doctrine of the contract formation by electronic data message, time of dispatch and receipt of data message, error in electronic communication, contract form and electronic signature could be supported or protected by the existing contract doctrine. Second, In relation to the contract formation arranged by electronic agents, the established contract doctrine provides no clear answer to the question whether changes provided by the interaction of electronic agents are enforceable. The enforceability question is left to future legislation. Finally, It is necessary that a significant level of formality together with the disclosure on the contract formality by certain act be conveyed 10 a potential buyer so that the buyer is impressed that the contact by the certain act could be valid.

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The inhibiory effect of glycyrrhizin and flavonoids on the reductive metabolism of glucocorticoid by the rat cecal contents.

  • Kong, Hye-Sik;Kim, In-Ho;Kim, Young-Soo;Choi, Boh-Im;Doh, Min-Ju;Kim, Young-Mi
    • 대한약학회:학술대회논문집
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    • 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.1
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    • pp.248.1-248.1
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    • 2003
  • Glucocorticoids are used most widely for the treatment of inflammatory bowel disease (IBD). For the efficient treatment and reduction of side effects, colon-specific delivery of a glucocorticoid is highly desirable. Previously, we synthesized prednisolone 21-sulfate sodium (PDS) as a colon-specific prod rug of prednisolone (PD) expecting that it might be stable and nonabsorbable in the upper intestine and hydrolyze in the colon to release PD. (omitted)

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EXTERNAL GEL FORMULATIONS OF PROSTAGLANDIN E1 ETHYL ESTER

  • Kim, Hee-Kyu;Kim, Jong-Seok;Lee, Sang-Kil;Yang, Sung-Woon;Lee, Ji-Eun;Choi, Han-Gon;Yong, Chulsoon;Choi, Young-Wook
    • 대한약학회:학술대회논문집
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    • 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.1
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    • pp.296.1-296.1
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    • 2003
  • Purpose. External gel formulations of prostaglandin E1 ethyl ester (PGE1-EE), a prod rug of PGE1 as a therapeutic agent for erectile dysfunction, were tried and evaluated by in vitro skin penetration characteristics and in vivo pharmacodynamic effects in cat. Method. The in vitro skin penetration was performed with Franz diffusion cell and examined in aspects of alcohol/polyol ratios and various enhancers. (omitted)

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Ray형 수중글라이더 소형 축소모델 개발 및 성능시험 (Development of Small-sized Model of Ray-type Underwater Glider and Performance Test)

  • 최형식;이성욱;강현석;;김서강;정성훈;;김준영
    • 한국항행학회논문지
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    • 제21권6호
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    • pp.537-543
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    • 2017
  • 수중글라이더(UG; underwater glider)는 지속적인 해양관측 탐사를 목적으로 개발된 장기운용 가능한 수중로봇이다. 원통형의 일반적인 수중글라이더는 단일 부력엔진과 자세제어기를 통해 추진하기 때문에, 운동조종성능 측면에서 효율적이지 못하다. 본 논문에서는 기존 원통형 수중글라이더의 부력제어 및 운동제어성능을 개선하기 위해 이중부력엔진을 탑재한 가오리 형태의 수중글라이더를 소개한다. CFD(computational fluid dynamics) 해석을 수행하여 설계된 형상의 글라이드 운동에 대한 유체저항성능을 해석한다. 산출한 유체력 계수를 바탕으로 운동 시뮬레이션을 수행하여 운동성능을 비교 분석한다. 가오리 형태의 수중글라이더 소형 축소모델을 제작하고, 제어시스템을 구성하여 기초 성능시험을 수행한다.

장기요양시설 노인의 환자구성에 관한 연구 (Study on Case-Mix in Long-Term Care Facilities for Elderly)

  • 이지전;김석일;유승흠;이상욱
    • 한국병원경영학회지
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    • 제6권3호
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    • pp.130-147
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    • 2001
  • This study is about major symptoms of elderly and medical services for elderly in long-tenn care facilities. The subject of this study was 298 patients over 00 years old staying in two geriatric hospitals and two nursing homes. The symptoms and medical services were level of patient classification from RUG(Resource Utilization Group)-III which is applied for both Medicare and Medicaid for skilled nursing facilities reimbursement system in US and designed for measuring patient characteristics and medical staff time. This classification is explained by each patient resource(staff time) utilization level which is called CMI(Case-Mix Index). In this study, the symptoms and services were compared by facility type and they were categorized by level and compared by CMI. Major findings are as follows; 1. There were more elderly who have cognitive function problems in nursing homes than patients in geriatric hospitals. There were more patients with behavioral problems in geriatric hospitals than residents in nursing homes. These results were both statistically significant. 2. The patients in geriatric hospitals received significantly more nursing rehabilitation services, rehabilitation services and extensive services than residents in nursing homes. Other hands, special care services were provided significantly more to residents in nursing homes than elderly in geriatric hospitals. 3. ADL and depression variables had higher CMI when the symptoms were heavier condition. The CMI were not matched with levels of cognitive function problems and behavioral problems. 4. The CMI matched well significantly with levels of nursing rehabilitation services, special care services, and clinically complex services provided for the patient in geriatric hospitals and only nursing rehabilitation services in nursing homes. The CMI for rehabilitation services level and extensive services had regular trends. From the result of this study, the resource utilization level and services provided for elderly in each long-term care facilities were figured out. For the further study, it needs to have more concern about RUG-ill which classification variables were just analyzed.

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Preparation of Highly Water Soluble Tacrolimus Derivatives: Poly(Ethylene Glycol) Esters as Potential Prod rugs

  • Chung, Yong-Seog;Cho, Hoon
    • Archives of Pharmacal Research
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    • 제27권8호
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    • pp.878-883
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    • 2004
  • Tacrolimus (FK506), which is isolated from Streptomyces tsukubaensis, is a new potent immu-nosuppressant. Because of poor solubility in water, the conventional intravenous dosage forms of tacrolimus contain surfactants such as cremophor EL (BASF Wyandotte Co.) or hydroge-nated polyoxy 60 castor oil (HCO-60) which may cause adverse effects. This study relates to a polymer-tacrolimus conjugate, which can be dissolved in water, formed by chemically binding the sparingly soluble drug, tacrolimus, with the water soluble polymer, methoxypoly(ethylene glycol) (mPEG). Water soluble tacrolimus-mPEG conjugates have been synthesized and shown to be function in vitro as prodrugs. These conjugates are in the form of an ester wherein the 24-, 32- or 24,32-positions are esterified. The desired 24-, 32- or 24,32-esterified com-pounds were obtained by initially acylating of tacrolimus with iodoacetic acid at the 24-,32-, or 24,32-positions and then reacting the resulting acylated tacrolimus with a mPEG in the pres-ence of a base such as sodium bicarbonate. These conjugates were converted again into tac-rolimus by the action of enzymes in human liver homogenate, and the half-lives of the conjugates are approximately 10 min in the homogenate, indicating that the esterified tacroli-mus derivatives may be practically applicable as a prod rug for the immunosuppressant.

페르시아 카페트에 표현된 디자인 구도 및 패턴특징에 관한 연구 (A Study on Types of Design Composition and Characteristics of Patterns Expressed in Persian Carpets)

  • 김희선
    • 한국의상디자인학회지
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    • 제5권1호
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    • pp.25-32
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    • 2003
  • The purpose of this study is to categorize the types of design composition and analyse the characteristics of patterns expressed in persian carpets. For this study, 188 works of Persian carpets were selected out in the book "Carpet & Rug" and contents in the internet sites of www. carpetwordwide.net/, www.jafarnet.com/. The types of design composition expressed in Persian carpets were classified into the following categories. 1) Medallion design composition 2) Mihrab design composition 3) All over design composition 4) Vase design composition 5) Garden design composition 6) Moharamat design composition 7) Painting design composition 8) Tree of Life design composition 9) Plant Pattern design composition 10) Mosaic pattern design composition. Patterns expressed in Persian carpets were Mosk pattern, Tree of life pattern, Lotus pattern being related to their religion and Hunting picture patterns related to their real life. In particular, various patterns of beautiful flowers, plants, trees, animals such as birds, insects and stream, beauriful landscapes were expressed in Persian carpets.

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