• 한국컴퓨터정보학회논문지
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• 제19권12호
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• pp.71-80
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• 2014

최근 무선기술의 발전으로 인해 스마트폰과 같은 이동노드는 멀티인터페이스를 장착하고 있다. 이와 같은 특징은 이동노드가 멀티네트워크에 동시 접속을 가능하게 하고 있다. 이에 따라 멀티인터페이스를 활용할 수 있는 다양한 네트워킹 연구가 진행되었다. 본 논문에서는 이와 관련해서 멀티인터페이스 이동노드가 PMIPv6 도메인에 접속한 환경에서 핸드오버 발생 시 데이터 손실을 줄일 수 있는 MPTCP 기반의 핸드오버 기법을 제안한다. 제안하는 핸드오버 기법은 특정 네트워크 인터페이스의 핸드오버 수행 시 멀티인터페이스를 통해 2 단계 플로우 이동성을 수행하고 MPTCP 서브플로우 기능을 통해 단대단 끊김 현상을 극복한다. 따라서 제안하는 기법으로 이동노드의 핸드오버 시 발생하는 데이터 손실을 줄이고 핸드오버 지연을 최소화 할 수 있는 장점을 가지고 있다.

• 한국수자원학회논문집
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• 제46권9호
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• pp.909-919
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• 2013

본 연구에서는 실내실험을 통하여 식생의 변화에 따른 하도의 수리학적특성, 저수로의 변화, 사주의 거동, 하안의 안정성 등을 정량적으로 파악하였다. 실내실험은 기존에 인공식생 대신에 수로에서 실제식생인 알팔파를 성장시켜서 수행하였다. 식생대에서는 유속이 매우 느리며, 저수로의 이동이 감소하였다. 2중 퓨리에 해석 결과, 교호사주의 특성을 나타낸 1-1모드의 진폭이 지배적이지만, 시간이 증가하면서 복렬사주의 특성을 나타내는 2-2와 2-3모드의 진폭이 증가하였다. 식생에 의하여 저수로가 고착화 되어 하도의 안정성이 증가하고, 하도 내 사주의 이동속도는 감소하지만, 하상이 불규칙하게 변하면서, 사주의 수는 증가하였다. 식생의 밀도가 증감함에 따라 하안의 안정성은 증가하였다. 식생의 밀도가 증가함에 따라 유사의 유출량과 유출량의 변동성이 감소하였다. 또한 망상화 강도는 감소하지만, 하도의 상관계수와 하상의 기복지수(BRI)는 증가하는 특성을 보여주었다.

• Archives of Plastic Surgery
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• 제35권4호
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• pp.393-399
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• 2008

Purpose: Chronic infected wounds sustained over 4 weeks with exposed tendon or bone are difficult challenges to plastic surgeons. Vacuum assisted closure (VAC) device has been well used for the management of chronic wounds diminishing wound edema, reducing bacterial colonization, promoting formation of granulation tissue and local blood flow by negative pressure to wounds. But Commercial ready-made VAC device might have some difficulties to use because of its high expenses and heavy weight. So we modified traditional VAC device with silver dressing materials as topical therapeutic agents for control of superimposed bacterial wound infection such as MRSA, MRSE and peudomonas. Methods: We designed the modified VAC device using wall suction, 400 cc Hemovac and combined slow release silver dressing materials. We compared 5 consecutive patients' data treated by commercial ready-made VAC device(Group A) with 11 consecutive patients' data treated by modified VAC device combined with silver dressing materials(group B) from September 2004 to June 2007. Granulation tissue growth, wound discharge, wound culture and wound dressing expenses were compared between the two groups. Results: In comparison of results, no statistical differences were identified in reducing rate of wound size between group A and B. Wound discharge was significantly decreased in both groups. Modified VAC device with silver dressing materials showed advantages of convenience, cost effectiveness and bacterial reversion. Conclusion: In combination of modified VAC device and silver dressing materials, our results demonstrated the usefulness of managing chronic open wounds superimposed bacterial infection, cost effectiveness compared with traditional VAC device and improvement of patient mobility.

• 센서학회지
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• 제23권2호
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• pp.114-121
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• 2014

We report a polysilicon active area membrane field effect transistor (PSAFET) pressure sensor for low stress deflection of membrane. The PSAFET was produced in conventional FET semiconductor fabrication and backside wet etching. The PSAFET located at the front side measured pressure change using 300 nm thin-nitride membrane when a membrane was slightly strained by the small deflection of membrane shape from backside with any physical force. The PSAFET showed high sensitivity around threshold voltage, because threshold voltage variation was composed of fractional function form in sensitivity equation of current variation. When gate voltage was biased close to threshold voltage, a fractional function form had infinite value at $V_{tn}$, which increased the current variation of sensitivity. Threshold voltage effect was dominant right after the PSAFET was turned on. Narrow transistor channel established by small current flow was choked because electron could barely cross drain-source electrodes. When gate voltage was far from threshold voltage, threshold voltage effect converged to zero in fractional form of threshold voltage variations and drain current change was mostly determined by mobility changes. As the PSAFET fabrication was compatible with a polysilicon FET in CMOS fabrication, it could be adapted in low pressure sensor and bio molecular sensor.

• IMMUNE NETWORK
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• 제2권1호
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• pp.25-34
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• 2002

Background: Rheumatoid arthritis (RA) is a chronic inflammatory disease characterized by synovial hyperplasia and joint destruction. The synovial fibroblasts express cell adhesion molecules and have a role in adhesive interation with inflammatory cells in synovial tissue. It has been suggested that hypoxic conditioins are thought to exist in arthritic joints, and several studies indicate that reactive oxygen species (ROS) produced in hypoxic condition can initiate events that lead to pro-adhesive changes via increased expression of adhesion molecules. So, this study wsa designed to examine whether antioxidant can inhibit hypoxia-induced expression of ICAM-1 in cultured human synovial fibroblasts. Methods: Synovial fibroblasts were isolated from synovial tissue in patients with RA and cultured at hypoxic condition. Antioxidant, PDTC (pyrrolidine dithiocarbamate) were pre-treated for an hour before the hypoxic culture and synovial fibroblasts were harvested at 0, 6, 12, 24, 48 hours time points. Cell surface ICAM-1 expression in synovial fibroblasts was examined by the flow cytometric analysis. To analyse the expression of ICAM-1 mRNA, reverse-transcriptase polymerase chain reaction (RT-PCR) was performed. The levels of cytokines in culture supernatants were measured by ELISA, and activation of NF-${\kappa}B$ was analysed by electrophoretic mobility shift assay. The adhesive reaction between synovial fibroblasts and lymphocytes was assayed by measurement of fluorescent intensity of BCECF-AM in lymphocytes. Results: Hypoxic stimuli up-regulated the ICAM-1 expression as well as the adhesive interaction of human synvial fibroblasts to lymphocytes in a time-dependent manner, and PDTC inhibited hpyoxia-induced ICAM-1 expression and cell-cell interaction. PDTC also inhibited the hypoxia-induced activation of intracellular transcription factor, NF-${\kappa}B$. PDTC decreased the amount of hypoxia-induced production of IL-$1{\beta}$ and TNF-${\alpha}$. Conclusion: These studies demonstrate that PDTC inhibit the hypoxia-induced expression of the adhesion molecule, ICAM-1 and activation of NF-${\kappa}B$ in cultured human synovial fibroblasts.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2017년도 춘계학술대회
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• pp.294-296
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• 2017

클라우드 컴퓨팅은 클라우드 노드에서 발생하는 모든 데이터를 클라우드 서버에 업로드하여, 서비스로서 사용자에게 제공하는 역할을 수행하는 컴퓨팅 기법이다. 이는 네트워크의 상황에 따라 실시간으로 서비스를 제공하기에는 어렵다. 그것은 로컬의 영역이 아니라 네트워크를 통하여 원격지로 정보를 전송하고, 클라우드에서 서비스를 제공하기 위해 추가적으로 다운로드를 해야 하기 때문이다. 이에 대한 대안으로 포그 컴퓨팅이 제안되었다. 본 논문에서는 클라우드, 포그 그리고 사용자 간의 효율적인 데이터 교환 기법을 제안하고자 한다. 제안된 포그는 사용자에게 서비스를 제공하고, 데이터를 수집하여 처리하도록 한다. 클라우드는 포그 간의 데이터 교환과 제어의 흐름을 담당하도록 한다. 우리는 이에 대한 데이터의 교환에 필요한 표준 방식을 제안한다. 이를 위한 적용은 BAN(Body Area Network)에서 발생하는 정보를 포그에서 처리 및 서비스를 하고, 클라우드는 중재 역할을 수행하는 시스템으로 한다. 이는 기기 또는 서비스 간에서 발생하는 데이터 이질성을 해결하고, 효율적인 데이터 이동을 제공할 수 있다.

• 한국전기전자재료학회논문지
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• 제21권9호
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• pp.835-843
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• 2008

We have fabricated the source-drain electrodes for OTFTs by screen printing method and manufactured Ag pastes as conductive paste. To obtain excellent conductivity and screen-printability of Ag pastes, the dispersion characteristics of Ag pastes prepared from two types of acryl resins with different molecular structures and Ag powder treated with caprylic acid, triethanol amine and dodecane thiol as surfactant respectively were investigated. The Ag pastes containing Ag powder treated with dodecane thiol having thiol as anchor group or AA4123 with carboxyl group(COOH) of hydrophilic group as binder resin exhibited excellent dispersity. But, Ag pastes(CA-41, TA-41, DT-41) prepared from AA4123 fabricated the insulating layer since the strong interaction between surface of Ag powder and carboxyl group(COOH) of AA4123 interfered with the formation of conduction path among Ag powders. The viscosity behavior of Ag pastes exhibited shear-thinning flow in the high shear rate range and the pastes with bad dispersion characteristic demonstrated higher shear-thinning index than those with good dispersity due to the weak flocculated network structure. The output curve of OTFT device with a channel length of 107 ${\mu}m$ using screen-printed S-D electrodes from DT-30 showed good saturation behavior and no significant contact resistance. And this device exhibited a saturation mobility of $4.0{\times}10^{-3}$ $cm^2/Vs$, on/off current ratio of about $10^5$ and a threshold voltage of about 0.7 V.

• 동의생리병리학회지
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• 제37권6호
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• pp.165-171
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• 2023

COVID-19 infection heightens the risk of thromboembolism. To see the similarities between the COVID-19 infection and Taeyang blood retention pattern, we conducted a PubMed search using specific terms related to blood circulation issues in the context of COVID-19, summarizing findings from 13 cases and 4 observational studies involving actual patients. Patients with COVID-19 are at risk of blood coagulation due to factors such as viral-induced cytokine storms, vascular endothelial dysfunction, reduced mobility in bedridden or isolated individuals, and resulting constipation. Additionally, cytokine storms and severe inflammation can lead to delirium in COVID-19 patients. The Taeyang blood retention pattern manifests as symptoms arising from delirium and an increased blood coagulation tendency in patients with a robust immune response. According to the Sanghan theory, certain herbal treatments can alleviate symptoms in patients with a tight lower abdomen who do not experience urinary issues. Studies show that components like Persicae Semen and Rhei Redix et Rhizoma in these prescriptions enhance blood circulation and reduce hypercoagulability. Additionally, these treatments aim to promote blood flow by relieving abdominal pressure through facilitating bowel movements. The excessive inflammation and heightened blood coagulation tendency in COVID-19 resemble the Taeyang blood retention pattern, although they are caused by different pathogens. Reinterpreting classical oriental medicine's principles in a modern context may enhance our understanding of traditional East Asian Medicine and foster future developments.

• Journal of Ginseng Research
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• 제48권2호
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• pp.190-201
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• 2024

Background: Deposition of immune complexes drives podocyte injury acting in the initial phase of lupus nephritis (LN), a process mediated by B cell involvement. Accordingly, targeting B cell subsets represents a potential therapeutic approach for LN. Ginsenoside compound K (CK), a bioavailable component of ginseng, possesses nephritis benefits in lupus-prone mice; however, the underlying mechanisms involving B cell subpopulations remain elusive. Methods: Female MRL/lpr mice were administered CK (40 mg/kg) intragastrically for 10 weeks, followed by measurements of anti-dsDNA antibodies, inflammatory chemokines, and metabolite profiles on renal samples. Podocyte function and ultrastructure were detected. Publicly available single-cell RNA sequencing data and flow cytometry analysis were employed to investigate B cell subpopulations. Metabolomics analysis was adopted. SIRT1 and AMPK expression were analyzed by immunoblotting and immunofluorescence assays. Results: CK reduced proteinuria and protected podocyte ultrastructure in MRL/lpr mice by suppressing circulating anti-dsDNA antibodies and mitigating systemic inflammation. It activated B cell-specific SIRT1 and AMPK with Rhamnose accumulation, hindering the conversion of renal B cells into plasma cells. This cascade facilitated the resolution of local renal inflammation. CK facilitated the clearance of deposited immune complexes, thus reinstating podocyte morphology and mobility by normalizing the expression of nephrin and SYNPO. Conclusions: Our study reveals the synergistic interplay between SIRT1 and AMPK, orchestrating the restoration of renal B cell subsets. This process effectively mitigates immune complex deposition and preserves podocyte function. Accordingly, CK emerges as a promising therapeutic agent, potentially alleviating the hyperactivity of renal B cell subsets during LN.

• Asian Pacific Journal of Cancer Prevention
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• 제14권4호
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• pp.2325-2331
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• 2013

Objective: To detect effects of plumbagin on proliferation and apoptosis in non-small cell lung cancer cell lines, and investigate the underlying mechanisms. Materials and Methods: Human non-small cell lung cancer cell lines A549, H292 and H460 were treated with various concentrations of plumbagin. Cell proliferation rates was determined using both cell counting kit-8 (CCK-8) and clonogenic assays. Apoptosis was detected by annexin V/propidium iodide double-labeled flow cytometry and TUNEL assay. The levels of reactive oxygen species (ROS) were detected by flow cytometry. Activity of NF-${\kappa}B$ was examined by electrophoretic mobility shift assay (EMSA) and luciferase reporter assay. Western blotting was used to assess the expression of both NF-${\kappa}B$ regulated apoptotic-related gene and activation of p65 and $I{\kappa}B{\kappa}$. Results: Plumbagin dose-dependently inhibited proliferation of the lung cancer cells. The IC50 values of plumbagin in A549, H292, and H460 cells were 10.3 ${\mu}mol/L$, 7.3 ${\mu}mol/L$, and 6.1 ${\mu}mol/L$ for 12 hours, respectively. The compound concentration-dependently induced apoptosis of the three cell lines. Treatment with plumbagin increased the intracellular level of ROS, and inhibited the activation of NK-${\kappa}B$. In addition to inhibition of NF-${\kappa}B$/p65 nuclear translocation, the compound also suppressed the degradation of $I{\kappa}B{\kappa}$. ROS scavenger NAC highly reversed the effect of plumbagin on apoptosis and inactivation of NK-${\kappa}B$ in H460 cell line. Treatment with plumbagin also increased the activity of caspase-9 and caspase-3, downregulated the expression of Bcl-2, upregulated the expression of Bax, Bak, and CytC. Conclusions: Plumbagin inhibits cell growth and induces apoptosis in human lung cancer cells through an NF-${\kappa}B$-regulated mitochondrial-mediated pathway, involving activation of ROS.