• Journal of Pharmaceutical Investigation
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• 제40권5호
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• pp.313-319
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• 2010

The objectives of this study were to evaluate the effect of formulation ingredients on the drug release and to optimize the novel sustained release matrix tablet formulations of bupropion hydrochloride. A three factor, three-level Box-Behnken design was used for the optimization procedure, with the amounts of PEO ($X_1$), citric acid ($X_2$) and Compritol 888 ATO ($X_3$) as the independent variables. The selected dependent variables were the cumulative percentage values of bupropion hydrochloride that had dissolved after 1, 4 and 8 hr. Various dissolution profiles of the drug from sustained release matrix tablets were obtained. Optimization was performed for $X_1$, $X_2$ and $X_3$ using the following target ranges; $30%{\leq}Y_1{\leq}45%$; $70{\leq}Y_2{\leq}85%$; $85%{\leq}Y_3{\leq}100%$. The optimized formulation for bupropion hydrochloride was achieved with 12.5% PEO ($X_1$), 2.5% citric acid ($X_2$) and 10% Compritol 888 ATO ($X_3$). The sustained release matrix tablets with the optimized formulation provided a release profile that was close to predicted values. In addition, the dissolution profiles of the sustained release matrix tablet with the optimized formulation were similar to those of the commercial product Wellbutrin$^{(R)}$ SR tablets ($f_2$=79.83).

• 물과 미래
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• 제28권2호
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• pp.155-168
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• 1995

본고는 개수로 마찰계수를 산정하거나 단면평균유속을 구하는 전통적인 방법의 경험식을 논의하였으며, 새로운 형태의 산정식을 제시하였다. 기존 경험식중 형태가 가능한 것은 차원의 일치를 기하기 위하여 수정하였으며, 등가조고를 도입하여 새로운 형태의 경험식을 제안하였다. 개수로에서의 마찰계수 분포도 원형판에서의 완난류 마찰계수 분포와 유사함을 고려하여 대부분의 관측자료는 완난류 구간에 드는 것으로 판단하였으며, 원형관 완난류 마찰계수 산정식을 수정하여 사각형 개수로 완난류 마찰계수 산정식을 개발하였다. 또한 차원의 일치를 이룬 새로운 형태의 경험식들을 포함하여 이들 산정식을 Bazin의 실험자료에 적용하여 비교 검토하였다.

• Korea-Australia Rheology Journal
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• 제21권1호
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• pp.13-16
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• 2009

We investigate time-temperature superposition from the viewpoint of geometry. The arc length of viscoelastic plots provides powerful resolution for check of the validity of time-temperature superposition. We also suggest a new algorithm for determination of shift factor which is base on the minimization of the total arc length and does not assume any functional form of viscoelastic function.

• Kyungpook Mathematical Journal
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• 제48권1호
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• pp.93-100
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• 2008

In this paper, by introducing some parameters and estimating the weight function, we give a new Hilbert-type integral inequality with a best constant factor. The equivalent inequality and the reverse forms are considered.

• Biomolecules & Therapeutics
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• 제31권4호
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• pp.456-465
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• 2023

Cervical tumors represent a prevalent form of cancer affecting women worldwide; current treatment options involve surgery, radiotherapy, and chemotherapy. Angiogenesis, the process of new blood vessel formation, is a crucial factor in cervical tumor growth. The molecular mechanisms underlying the effects of the liver kinase B1 (LKB1/STK11) tumor suppressor protein on tumor angiogenesis have not been elucidated. Therefore, we investigated the role of LKB1 in cervical tumor angiogenesis both in vitro and in vivo in this study. Our results demonstrated that LKB1 inhibited cervical tumor angiogenesis by suppressing the expression of angiogenesis-related factors such as vascular endothelial growth factor (VEGF) and hypoxia inducible factor-1α. LKB1 directly affected both carcinoma and vascular endothelial cells, resulting in a significant reduction in tumor growth and angiogenesis. Furthermore, LKB1 was found to bind to VEGF receptor 2 (VEGFR-2) and target the VEGFR-2-mediated protein kinase B/mechanistic target of rapamycin signaling pathway in endothelial cells, thereby reducing cervical tumor growth and angiogenesis. Our study provides new insights into the molecular mechanisms underlying the anti-tumor and anti-angiogenic effects of LKB1 in cervical cancer. These findings will help develop new therapeutic strategies for cervical cancer.

• 대한조선학회논문집
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• 제54권3호
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• pp.171-186
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• 2017

This paper introduces a study on ship performance in waves to consider the effects of added resistance in the early stage of hull-form design. A ship experiences a loss of speed in actual seaways, hence this study proposes the overall procedure of a new design concept that takes into account the hydrodynamic performance of ship in waves. In the procedure, the added resistance is predicted using numerical methods: slender-body theory and Maruo's far-field formulation, since these methods are efficient in initial design stage, and an empirical formula is adopted for short waves. As computational models, KVLCC2 hull and Supramax bulk carrier are considered, and the results of added resistance and weather factor for test models are discussed. The computational results of vertical motion response and added resistance of KVLCC2 hull are compared with the experimental data. In addition, the sensitivity analysis of added resistance and weather factor for KVLCC2 hull to the variations of ship dimensions are conducted, and the change of the added resistance and propulsion factors after hull form variations are discussed.

• BMB Reports
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• 제36권1호
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• pp.120-127
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• 2003

The formation of new blood vessels, angiogenesis, is an essential process during development and disease. Angiogenesis is well known as a crucial step in tumor growth and progression. Angiogenesis is induced by hypoxic conditions and regulated by the hypoxia-inducible factor 1 (HIF-1). The expression of HIF-1 correlates with hypoxia-induced angiogenesis as a result of the induction of the major HIF-1 target gene, vascular endothelial cell growth factor (VEGF). In this review, a brief overview of the mechanism of angiogenesis is discussed, focusing on the regulatory processes of the HIF-1 transcription factor. HIF-1 consists of a constitutively expressed HIF-1 beta(HIF-1β) subunit and an oxygen-regulated HIF-1 alpha(HIF-1α) subunit. The stability and activity of HIF-1α are regulated by the interaction with various proteins, such as pVHL, p53, and p300/CBP as well as by post-translational modifications, hydroxylation, acetylation, and phosphorylation. It was recently reported that HIF-1α binds a co-activator of the AP-1 transciption factor, Jab-1, which inhibits the p53-dependent degradation of HIF-1 and enhances the transcriptional activity of HIF-1 and the subsequent VEGF expression under hypoxic conditions. ARD1 acetylates HIF-1α and stimulates pVHL-mediated ubiquitination of HIF-1α. With a growing knowledge of the molecular mechanisms in this field, novel strategies to prevent tumor angiogenesis can be developed, and form these, new anticancer therapies may arise.

• 전기학회논문지
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• 제66권12호
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• pp.1899-1904
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• 2017

This paper presents a new one-time password approach generated based on $4{\times}4$ pattern schedule. It demonstrates generation of passkey from initial seed of random codes and mapping out in table pattern schedule which will produce a new form of OTP scheme in protecting information or data. The OTP-2FA has been recognized by many organizations as a landmark to authentication techniques. OTP is the solution to the shortcomings of the traditional user name/password authentication. With the application of OTP, some have benefited already while others have had second thoughts because of some considerations like cryptographic issue. This paper presents a new method of algorithmic approach based on table schedule (grid authentication). The generation of OTP will be based on the random parameters that will be mapped out in rows and columns allowing the user to form the XY values to get the appropriate values. The algorithm will capture the values and extract the predefined characters that produce the OTP codes. This scheme can work in any information verification system to enhance the security, trust and confidence of the user.

• 한국수소및신에너지학회논문집
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• 제26권1호
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• pp.1-7
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• 2015

In this study, characteristics of reforming process of automotive liquefied petroleum gas (LPG) fuel using plasma reactor are investigated. Because plasma reformer technology has advantages of a fast start-up and wide fuel/oxidizer ratio of operation, and reactor size is smaller and more simple compared to typical combustor and catalytic reactor, plasma reforming is suitable to the on-board vehicle reformer. To evaluate the characteristics of the reforming process, parametric effect of $O_2/C$ ratios, reactant flow rate and metal form on the process were investigated. In the test of varying $O_2/C$ ratio from partial oxidation to stoichiometry combustion, conversion of LPG was increased but selectivity of $H_2$ decreased. The optimum condition of $O_2/C$ ratio for the highest $H_2$ yield was determined to be around 1.0 for 20~50 lpm, and 1.35 for 100 lpm. Specific energy density (SED) was major factor in reforming process and higher SED leads to higher $H_2$ yield. And metal form in the reformer increased $H_2$ yield of about 34 % as compared to the case of no metal form. The result can be a guide to map optimal condition of reforming process.

• 한국강구조학회 논문집
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• 제23권2호
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• pp.189-198
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• 2011

최근 건축물들이 미적인 아름다움을 추구하며 점차 비정형화 되어감에 따라 이를 실현시켜 주기 위한 새로운 구조시스템들이 개발되고 있다. Diagrid system은 외각에 배치 된 경사진 기둥을 통해 구조물의 중력하중과 횡력을 모두 저항하는 시스템으로 건물 내부에 기둥이 없어 비교적 평면 변화에 유리한 시스템이다. 하지만 현행의 내진설계 기준에는 이와 같은 새로운 구조시스템에 대한 내진성능계수가 명시되어 있지 않다. 이에 새로운 내진성능 평가 방법인 ATC-63이 제안되었다. 본 논문에서는 구조물의 비정형성을 고려해주기 위해 3D 비선형 해석 모델에 각각 작용하는 하중의 방향을 달리하며 ATC-63에서 제시하고 있는 절차에 따라 비정형 Diagrid system의 내진성능을 평가하였다.