• International Journal of Naval Architecture and Ocean Engineering
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• v.12 no.1
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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.

• Journal of Pharmaceutical Investigation
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• v.22 no.2
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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.

• Journal of the Society of Disaster Information
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• v.19 no.4
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• pp.908-915
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• 2023

Purpose: The purpose of this study is to examine the types of fraudulent crimes among various crimes taking place during NFT transactions, and to approach institutional problems caused by crime types analysis and crackdown methods and legal limitations. Method: IIn order to classify the types of fraudulent crimes that appear in NFT transactions, the crime types were analyzed through the results of previous studies and cases of current incidents. Result: Most of the crimes that are taking place through NFTs are various types of fraudulent crimes such as rug pools, thefts, personal information theft fraud, and pig murder. Therefore, these types were classified and various damage cases were also analyzed. It is a matter of copyright. Conclusion: Currently, the financial problems caused by the occurrence of fraudulent crimes in NFTs worldwide are the most worrisome, and the scale will be even greater as the market grows in the future. Therefore, in Korea, various institutional supplements and policies should be prepared through analysis of crime types that can affect crime prevention and investigation and arrest activities.

• International Commerce and Information Review
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• v.5 no.2
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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.

• Proceedings of the PSK Conference
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• 2003.04a
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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)

• Proceedings of the PSK Conference
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• 2003.04a
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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)

• Journal of Advanced Navigation Technology
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• v.21 no.6
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• pp.537-543
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• 2017

Underwater glider is the long-term operating underwater robot that was developed with a purpose of continuous oceanographic observations and explorations. Torpedo-type underwater glider is not efficient from an aspect of maneuverability, because it uses a single buoyancy engine and motion controller for obtaining propulsive forces and moments. This paper introduces a ray-type underwater glider(RUG) with dual buoyancy engine, which improves the control performance of buoyancy and motion compared with torpedo-type underwater glider. Carrying out Computational Fluid Dynamics (CFD) analysis as static pitch drift test, the performance of fluid resistance for gliding motion was identified. Based on the calculated hydrodynamic coefficients, the dynamic simulation compared and analyzed the motion performance of torpedo-type and ray-type while controlling same volume of buoyancy engine. Small-sized model of RUG was developed to perform fundamental performance tests.

• Korea Journal of Hospital Management
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• v.6 no.3
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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.

• Archives of Pharmacal Research
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• v.27 no.8
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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.

• Journal of the Korea Fashion and Costume Design Association
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• v.5 no.1
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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.