• 약학회지
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• 제41권1호
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• pp.60-73
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• 1997

In order to design a 24 hr sustained release preparation of sulindac for oral administration, fast release pellet (FR), slow release pellet (SR) and two combined formulation (1 : 1 and 1 : 2) were prepared. The pharmacokinetic effect of such preparations has been evaluated using rabbits as a suitable in vivo model, and tested in man. Dose determination was carried out using curve fitting according to RSTPJP II program. In bioavailability test using rabbit, AUCs of sulindac in a few designed formulations were similar to each other. $C_{max}$- of RF and SR were 1.8 times and 1.2 times higher, respectively, compared to that of combined formulation (FR:SR=1:1). While plasma concentration of FR and SR decreased rapidly, that of combined formulation (FR:SR 1:1) lasted at the level close to $C_{max}$ for 24 hrs. Plasma concentration of sulfide form from the combined pellet(FR:SR=1:1) lasted for 24 hrs, and its AUC value was 1.4-fold, 2.7-fold. and 1.2-fold greater than FR pellet, SR pellet and combined pellet (FR:SR 1 : 2). Thus, the combined pellet of 1:1 ratio was found to be the most effective for oral sustained release formulation. Bioavailability test in human showed that AUC of sulfide from TSRP (1 : 1) was approximately 1.5 times greater than total AUC of Immbaron$^{\circledR}$ administered twice in a day. While $T_{max}$ of sulfide from lmmbaron$^{\circledR}$ was 4.33 +/- 1.37 hr (lst administration) and 3.33 ${pm}$ 0.82 hr (2nd administration), respectively, that of sulfide from TSRP increased to 7.17 ${pm}$ 2.86 hr. Plasma concentration of sulfide from TSRP was sustained at more, than 1.0 ${\mu}g{\cdot}$hr/ml until 24 hrs after one dose administration. In addition, TSRP may decrease local adverse reaction in the stomach, since plasma concentration of sulfide from the combined pellet was low within 2hrs in the stomach. In conclusion, it is suggested that TSRP formulation may be effective for oral 24 hr sustained release formulation of sulindac dosing 300 ~ 350mg once a day.

• 전자공학회논문지
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• 제50권5호
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• pp.25-38
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• 2013

미래의 무선 시스템은 사용자가 이동하며 생활하는 것을 지원해야 한다. 이동성은 매우 다른 특성을 가진 여러 개의 중첩 네트워크의 사용을 통해 제공 될 것이다. 이러한 네트워크는 오늘날의 인기 있는 데스크탑 서비스인 웹 브라우징, 쌍방향 멀티미디어 및 모바일 화상회의 등의 원활한 제공을 지원해야 한다. 따라서 이러한 모바일 시스템 설계의 주요 과제 중 하나는 서비스 품질(QoS) 보장이 될 것이며 이것은 애플리케이션이 다양한 네트워킹 인프라 아래에서 요구하는 것에 따라 보장해야 한다. 우리는 응용 프로그램에 QoS 보장을 제공하는 자원의 예약 및 적응 기법을 사용할 필요가 있다. 그러나 전체 서비스 예약 및 사전 구성은 지나치게 많아서 결과가 매우 비효율적이고 신뢰할 수도 없는 방식이다. 이것을 극복하기 위해 사용자의 이동성 패턴을 이용할 수 있다. 사용자의 움직임을 미리 알고 있을 경우, 예약 및 구성 절차는 사용자가 방문할 가능성이 있는 네트워크의 영역으로 제한할 수 있다. 제안한 Proxy-UMP기법은 다른 기법들에 비해 탐색비용의 증가에 민감하지 않으며, SMR(Session Mobility Ratio)증가에 따라 총비용의 증가율이 적은 것을 보여준다.

• 대한화장품학회지
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• 제36권2호
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• pp.115-120
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• 2010

피부에서 표피를 통한 물질의 수송은 피부의 여러 가지 보호 작용으로 인해 경피 흡수가 쉽게 이루어지지 않아 결과적으로 생리 활성 성분이 그 효과를 발휘하는 진피층까지 도달하기 어렵다. 본 연구는 피부에서 매우 낮은 농도가 투과되는 친수도가 높은 약물(알부틴)의 경피흡수를 촉진하는 화학적 촉진제의 in vitro 흡수 양상에 대한 연구이다. 화학적 촉진제로 N-methyl-2-pyrrolidone (NMP)을, 경피흡수장치는 Franz diffusion cell을 사용하였다. NMP는 약물의 경피흡수에 상당히 영향을 준다는 것을 알 수 있었다. NMP는 피부 지질층의 유동성에 영향을 주지 않고 약물의 보조흡수제로 작용하여 알부틴의 경피흡수촉진비율을 약 1.3~1.5배 증가 시켰지만 지연 시간의 변화는 없었다. 따라서 NMP는 친수성 생리활성 물질의 효과적인 화학적 경피흡수 촉진제로 작용하였으며, 향후 화장품 제형 및 약물전달체계에 응용이 기대된다.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2010년도 학술발표회
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• pp.774-778
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• 2010

상류에서 유입된 토사는 지표수를 오염시키고 때때로 퇴적이 발생시 심각한 문제들을 야기하게 된다. 본 연구에서는 GIS 기반의 경험적 토사유실모형을 통해 모의된 토사유실량과 관측된 유사량 자료를 이용하여 유사전달률 자료를 구축하였다. 모의된 토사유실량과 관측된 유사량과의 관계를 분석한 결과, 강우량에 의한 결정계수는 동향과 천천에 대해 각각 0.427과 0.667인 반면, 강우 강도에 의한 결정계수는 0.873과 0.927로 높게 나타났다. 자료의 검보정을 위해 2002-2005년도(보정)와 2006-2008년도(검증) 자료로 분류한 후 USLE 모형과 관측된 유사량을 이용하여 SDR을 계산하였다. 동향과 천천유역의 강우량에 의한 SDR의 평균은 각각 6.273과 3.353인 반면 강우강도에 의한 SDR의 평균은 4.799와 2.874로 낮게 나타났으며, 표준편차는 강우량의 3.746과 2.090에 비해 강우강도가 0.930과 0.407로 낮게 나타났다. 따라서 토사유실 모델링시 강우량에 의한 방법보다는 강우강도에 의한 SDR 추정값을 사용하는 것이 더 바람직함을 보여준다.

• Journal of Preventive Medicine and Public Health
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• 제9권1호
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• pp.109-116
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• 1976

Reorganization of myun health care service is one of the main issues in health care delivery in rural Korea. The fundamenta, concept of the role and function of the myun health subcenter is that it is the basic unit of rural health care service and is to provide comprehensive health care service through the integration of curative and preventive services. The aim of this study is to analyze the patterns of curative activities in the myun health subcenter in terms of the most prevalent types of diseases, necessary diagnostic methods and required equipment, types of treatment, necessary drugs and materials, and finally the cost of curative services. The population on which this study was done was the 1596 patients who visited the two myun health subcenters (Sunwon Myun and Naega Myun) in Kang Wha County, the area of the Yonsei University Community Health Teaching Project, during period from May 1, 1975 to June 10, 1976. For the patient's record in the clinic, problem oriented medical records were used. Decisions regarding the disease classification, the diagnostic methods used and selection of the most appropriate and adequate medical treatment were made by a group of three experienced physicians after reviewing the medical records which had been written by public physicians who were treating patients in the study area. The records were reviewed by resident staff members of the Department of Preventive Medicine, of Yonsei University College of Medicine. A brief summary of results of the study is as follow: 1. 29.9% of the patients who visited the clinics were ages between 0-4. No sex difference was observed among patients less than 20 years of age. However, among patients over 20 years old, females predominated. Thus it is evident that the majority of patients were either children or mothers and grandmothers. 2. The distance from the individual villages to the myun health subcenter was one of important factors in determining the ratio of clinic visits. However, other factors such as the activities of the health workers also affected the rates substantially. 3. The most common 25 diseases comprised 90.2% of all the diseases recorded. Acute respiratory infection (25.5%), Skin (12.7%) , diarrheal diseases (6.8%), neuralgia and back pain (4.9%) and. all other injuries (3.9%) were the five most common diseases. 4. Of all the diseases diagnosed and treated, 9.2% required simple laboratory tests for diagnosis, 6.5% required X-ray examination, and altogether 13.6% required either laboratory test or X-ray examination. 5. Treatment and management of 42.0% of the cases could be accomplished with simple, inexpensive drugs, 12.8% required the use of more expensive drugs (mostly antibiotics) and injections were required in 19.7% of the cases. Minor surgery and referral were necessary in 5% of the cases. 6. The cost for diagnosis and treatment was estimated with a standard which was set by general concensus. The average cost of diagnosis was 144 per case and the cost of treatment was 726 per case, The Total average cost per visit was 870.

• 한국재료학회지
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• 제14권2호
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• pp.90-93
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• 2004

Silicon dioxide thin films were deposited on p-type Si (100) substrates by atomic layer deposition (ALD) method using alternating exposures of $SiH_2$$Cl_2$ and $O_3$ at $300^{\circ}C$. $O_3$ was generated by corona discharge inside the delivery line of $O_2$. The oxide film was deposited mainly from $O_3$ not from $O_2$, because the deposited film was not observed without corona discharge under the same process conditions. The growth rate of the deposited films increased linearly with increasing the exposures of $SiH_2$$Cl_2$ and $O_3$ simultaneously, and was saturated at approximately 0.35 nm/cycle with the reactant exposures over $3.6 ${\times}$ 10^{9}$ /L. At a fixed $SiH_2$$Cl_2$ exposure of $1.2 ${\times}$ 10^{9}$L, growth rate increased with $O_3$ exposure and was saturated at approximately 0.28 nm/cycle with $O_3$ exposures over$ 2.4 ${\times}$ 10^{9}$ L. The composition of the deposited film also varied with the exposure of $O_3$. The [O]/[Si] ratio gradually increased up to 2 with increasing the exposure of $O_3$. Finally, the characteristics of ALD films were compared with those of the silicon oxide films deposited by conventional chemical vapor deposition (CVD) methods. The silicon oxide film prepared by ALD at $300^{\circ}C$ showed better stoichiometry and wet etch rate than those of the silicon oxide films deposited by low-pressure CVD (LPCVD) and atmospheric-pressure CVD (APCVD) at the deposition temperatures ranging from 400 to $800^{\circ}C$.

• 한국건축시공학회지
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• 제18권3호
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• pp.227-234
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• 2018

콘크리트의 특징은 그 품질을 확보함에 있어서 시멘트, 모래, 자갈, 물, 혼화재료 등 구성재료 개개의 품질 및 그 배합비 그리고 생산관리 및 시공관리, 양생 등에 의해 영향을 받는다는 점이다. 콘크리트 배합설계에 따라 시공연도와 강도가 변화하게 된다. 대부분의 건설현장은 동일구간에 여러 레미콘 회사의 제품을 동시에 타설하는 것이 일반적이나 표준시방서에는 혼합타설을 원칙적으로 금지하고 있으며 필요시 책임기술자의 확인을 받도록 규정되어 있다. 이 연구는 불가피한 혼합타설시 콘크리트 품질확보를 하기 위한 방안을 제시하고자 하였으며, 연구방법은 문헌검토, 설문조사를 통하여 혼합타설의 문제점을 파악하고 불가피함을 확인하였으며, 사례현장의 콘크리트 타설계획과 군산지역의 레미콘 회사의 현황을 통하여 혼합타설의 문제점을 파악하고 불가피함을 확인하였다. 혼합타설을 하지 않는 방법으로 5가지 안을 제시하여 그 중에서 지역별 표준배합설계를 작성하여 동일한 배합비로 11개 레미콘 회사로 하여금 생산하도록 하여 혼합타설의 위험성을 배제하였으며 그 과정의 문제점을 제시하였다. 향후 연구과제로는 본 연구를 통하여 검증되지 않은 방안인 레미콘 회사의 규모확장 및 통폐합, 혼합타설된 콘크리트의 품질 추적조사, 혼화제의 상응성테스트 그리고 콘크리트 강도의 조기판정기법의 개발 및 골재등의 재료 통일방안등을 연구하여 혼합타설시 피해를 최소화할 수있도록 해야 할 것이다.

• 대한예방한의학회지
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• 제14권3호
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• pp.1-12
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• 2010

Objective : Samulatang (herbal description) is much used for women's disease in Korean Traditional Medicine. The aim of this study is to evaluate reproductive toxic effect by Samultang in pregnant rats and fetuses, and ascertain a dose-response relationship Method : Pregnant Sprague-Dawley rats were administered with the Samultang at single, double and quadruple dose for 20 days, orally. Pregnant rats were sacrificed at 20th day of gestation, and observed internal and reproductive organs. Live fetuses of gestation were randomly selected and fixed in 95% ethanol. Fetuses were stained with alcian blue and alizarin red S. We observe maternal body weight,, index associated pregnancy, and skeletal malformations in fetus Result : Maternal body weight of Samultang treated group has increased, side effect was not found in maternal body compared to that of control group. There were no significant difference in internal and reproductive organs. Double concentration administered group had lowest value in number of implantation, live fetuses, implantation rate and delivery rate, Also double concentration administered group showed higher early and late resorption rate than the other group. But, these are not significant. In the sex ratio, number of females, bigger than number of males in all Samultang administered groups. The fetuses of dams treated with Samultang didn't showed external and skeletal malformation. Vertebral and sternal variations were observed in single, double and quadruple concentration administered group but, compared to the control, those variations were insignificant. There were no significant changes in number of ribs, cervical, thoracic, lumber, sacral and caudal vertebrae Conclusion : Samultang is not expected to affect on pregnant rats and fetus about maternal body weight and number of live fetuses. There were no significant changes in organ weight, reproductive organs. Although skeletal variations were showed in vertebrae and sternum, treated groups were shown insignificant changes in skeletal variation

• 정보처리학회논문지C
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• 제12C권3호
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• pp.429-436
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• 2005

모바일 애드혹 네트워크(MANET)는 어떤 고정 기반구조나 중앙 집중형 관리 구조를 갖지 않는 모바일 노드의 집합으로 구성된다. AODV (Ad hoc On-demand Distance Vector routing)는 MANET용 온디맨드(on-demand) 라우팅 프로토콜로서, IETF (Internet Engineering Task Force)의 MANET 워킹 그룹에 제출된 기고문(Internet Draft)이다. 본 논문에서는 최대의 노드 비중첩 및 링크 비중첩을 제공하고, AODV 프로토콜은 물론 기존의 AODV 기반 다중경로 프로토콜보다 성능이 우수한 새로운 최대 비중첩 다중경로 AODV (MDAODV) 프로토콜을 제안한다. 본 연구의 핵심 아이디어는 경로 요청(RREQ:Route REQuest) 메시지에 소스 라우팅(source routing) 주소 정보를 추가시켜 확장하는 것과 수신 노드가 일정 시간 동안 도착한 다수의 RREQ를 조사하여 2개의 경로를 선택하는 것이다. 제안한 MDAODV 프로토콜은 기존 다중경로 라우팅 프로토콜에 비해 높은 신뢰성과 우수한 견고성을 갖는 경로를 제공할 뿐만 아니라, 수신 노드에서 경로를 결정하므로 중간 노드에서의 오버헤드를 감소시킨다. 성능평가 결과에 의하면, 제안한 MDAODV 프로토콜은 기존의 AODV 기반 다중경로 프로토콜보다 패킷 전달율과 평균 지연시간의 측면에서 성능이 우수한 반면 라우팅 오버헤드는 오히려 감소하는 경향을 나타낸다.

• Journal of Pharmaceutical Investigation
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• 제38권2호
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• pp.127-134
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• 2008

Peroral administration is the most convenient one for the administration of pharmaceutically active compounds. Most of poorly water-soluble drugs administered via the oral route, however, remain poorly available due to their precipitation in the gastrointestinal (GI) tract and low permeability through intestinal mucosa. In this study, one of drug delivery carriers, lipid nanoparticles (LNPs) were designed in order to reduce side effects and improve solubility and stability in GI tract of the poorly water soluble drugs. However, plain LNPs are generally unstable in the GI tract and susceptible to the action of acids, bile salts and enzymes. Accordingly, the surface of LNPs was modified with polyethylene glycol (PEG) for the purpose of improving solubility and GI stability of paclitaxel (PTX) in vitro. PEG-modified LNPs containing PTX was prepared by spontaneous emulsification and solvent evaporation (SESE) method and characterized for mean particle diameter, entrapping efficiency, zeta potential value and in vitro GI stability. Mean particle diameter and zeta potential value of PEG-modified LNP containing PTX showed approximately 86.9 nm and -22.9 mV, respectively. PTX entrapping efficiency was about 70.5% determined by UV/VIS spectrophotometer. Futhermore, change of particle diameter of PTX-loaded PEG-LNPs in simulated GI fluids and bile fluid was evaluated as a criteria of GI stability. Particle diameter of PTX-loaded PEG-LNPs were preserved under 200 nm for 6 hrs in simulated GI fluids and bile fluid at $37^{\circ}C$ when DSPE-mPEG2000 was added to formulation of LNPs above 4 mole ratio. As a result, PEG-modified LNPs improved stability of plain LNPs that would aggregate in simulated GI fluids and bile solution. These results indicate that LNPs modified with biocompatible and nontoxic polymer such as PEG might be useful for enhancement of GI stability of poorly water-soluble drugs and they might affect PTX absorption affirmatively in gastrointestinal mucosa.