• 한국통신학회논문지
• /
• 제34권12A호
• /
• pp.962-970
• /
• 2009

본 논문에서는 Long Term Evolution (LTE) 시스템에서 새로 설치된 셀이 자율적으로 이웃 셀 정보를 수집하고 Physical Cell Identifier (PCI)를 결정하는 방안을 제안한다. PCI의 수는 한정되어 재사용이 필요하며, 도심 환경에서 Macro 셀 안에 Pico/Femto 셀과 같은 작은 크기의 셀이 다수 설치되면 PCI의 수는 더욱 제한될 것으로 예상된다. 따라서 제한된 수의 PCI를 효율적으로 할당하는 연구가 필요하다. 본 논문에서는 Self-Organization Network (SON) 환경에서 셀이 주변 셀들로부터 오는 수신신호세기를 수집하고, 이를 이용하여 PCI 재사용 효율을 높일 수 있도록 자율적으로 PCI를 할당하는 방안을 제안한다. 모의실험을 구성하여 제안한 방안이 적용된 경우의 성능을 분석하였고, 새로 설치되는 셀의 커버리지 타입에 따른 성능도 도출하고 분석하였다. 제안한 기법을 적용하면 시스템을 운용하는데 필요한 PCI의 수를 줄여 효율적으로 PCI를 재사용할 수 있음을 확인하였다

• IMMUNE NETWORK
• /
• 제11권3호
• /
• pp.135-154
• /
• 2011

The great discovery of microRNAs (miRNAs) has revolutionized current cell biology and medical science. miRNAs are small conserved non-coding RNA molecules that post-transcriptionally regulate gene expression by targeting the 3' untranslated region of specific messenger RNAs for degradation or translational repression. New members of the miRNA family are being discovered on a daily basis and emerging evidence has demonstrated that miRNAs play a major role in a wide range of developmental process including cell proliferation, cell cycle, cell differentiation, metabolism, apoptosis, developmental timing, neuronal cell fate, neuronal gene expression, brain morphogenesis, muscle differentiation and stem cell division. Moreover, a large number of studies have reported links between alterations of miRNA homeostasis and pathological conditions such as cancer, psychiatric and neurological diseases, cardiovascular disease, and autoimmune disease. Interestingly, in addition, miRNA deficiencies or excesses have been correlated with a number of clinically important diseases ranging from cancer to myocardial infarction. miRNAs can repress the gene translation of hundreds of their targets and are therefore well-positioned to target a multitude of cellular mechanisms. As a consequence of extensive participation in normal functions, it is quite logical to ask the question if abnormalities in miRNAs should have importance in human diseases. Great discoveries and rapid progress in the past few years on miRNAs provide the hope that miRNAs will in the near future have a great potential in the diagnosis and treatment of many diseases. Currently, an explosive literature has focussed on the role of miRNA in human cancer and cardiovascular disease. In this review, I briefly summarize the explosive current studies about involvement of miRNA in various human cancers and cardiovascular disease.

• 한국전산유체공학회:학술대회논문집
• /
• 한국전산유체공학회 2009년 추계학술대회논문집
• /
• pp.65-70
• /
• 2009

In this paper a hybrid grid generation program for general 2-D region is introduced. The program is developed by using JAVA programming language, and it can be used either as an application program on a local computer or as an applet in the network environment. The hybrid grid system for a 2-D problem means a combination of triangular cells and quadrilateral cells, and it can offer both of the high flexibility of triangular cells and the high accuracy and efficiency of structured-type quadrilateral cells. To accommodate a quadrilateral-cell region and a triangular-cell region into one computational domain, it is importance to take good care of the interface between two different regions so that overall good grid quality can be maintained. In this research advancing layer method(ALM) augmented by elliptic smoothing method is used for the quadrilateral-cell region and advancing front method(AFM) is used for the triangular-cell region. A special treatment technique for the interface between those two regions is also developed. The interface treatment technique is basically to prevent the propagation of small cell size due to ALM method into the triangular region and maintain the smooth transition of cell-size scale between two different regions. By applying current technique high-quality hybrid grids for general 2-D regions can be easily generated, and typical grid generation results and flow solutions are demonstrated.

• International Journal of Oral Biology
• /
• 제45권3호
• /
• pp.115-125
• /
• 2020

Resveratrol has been reported to exert anticancer activity via modulation of multiple pathways and genes. In this study, we examined the effect of resveratrol on YD-10B human oral squamous cell carcinoma cells and its molecular mechanisms of action. We found that resveratrol inhibited the proliferation of YD-10B cells in a dose- and time-dependent manner. The suppressive effect of resveratrol was accompanied by a reduction in Bmi-1 gene expression. We observed that silencing the Bmi-1 gene by small interfering RNA effectively downregulated the levels of GLUT1 mRNA and protein, which were also repressed by resveratrol. Bmi-1 silencing increased the number of YD-10B cells in S-phase arrest by approximately 2.3-fold compared with the control. In conclusion, the results of the present study demonstrate, for the first time, that resveratrol suppresses Bmi-1-mediated GLUT1 expression in human oral squamous cell carcinoma cells and suggest that the specific molecular targeting of Bmi-1 and/or GLUT1 expression can be combined with a chemotherapeutic strategy to improve the response of oral cancer cells to resveratrol.

• 한국통신학회논문지
• /
• 제40권7호
• /
• pp.1424-1432
• /
• 2015

해양 산업과 IT 기술의 융합으로 해상 통신에 대한 여러 무선통신 기술들이 논의됨에 따라 채널 선택에 따른 간섭 제어, 시간영역에서 간섭 제어 등 다양한 간섭 제어 방법이 시도되고 있다. 이를 위해 본 논문에서는 다양한 해양 통신 환경에서 시스템의 성능을 측정하고 검증 및 평가할 수 있도록 하향링크 시스템 레벨 시뮬레이터를 구현하였다. 제안하는 시뮬레이터는 기존의 이동통신 시뮬레이터와 달리 해상에서 선박 간 신호간섭을 조정할 수 있도록 3GPP Release 10의 주요 기술 enhanced inter-cell interference coordination(eICIC)을 적용하였다. 또한 개발한 시스템 레벨 시뮬레이터를 사용하여 eICIC의 주요 기술인 almost blank subframes(ABS)와 cell range expansion(CRE) 변화에 따른 소형 셀의 수율 분포를 도출하였다.

• ETRI Journal
• /
• 제38권1호
• /
• pp.112-122
• /
• 2016

This paper presents a set of candidate regulatory requirements for TV band devices (TVBDs) in the Rep. of Korea. To guarantee the protection of incumbent services, especially digital TV (DTV) and wireless microphones, in TV frequency bands, we suggest minimum separation distances of TVBDs from the noise-limited contour according to incumbent users and TVBD types. This paper also deals with multiple sets of separation distances of a co-channel TVBD network from a DTV protected contour on the basis of the radio propagation characteristics of different geographic areas to make good use of TV white space (TVWS) and safely protect the DTV service. We present a low-power transmission mode of TVBDs and the relevant separation distances for small-cell deployment. The service coverage reduction ratio of a TVBD network is investigated in the presence of DTV interference in four geographic areas. The TVWS field verification results, conducted on the island of Jeju (Rep. of Korea), show that incumbent services operate well without harmful interference from neighboring TVBDs with the proposed separation distances.

• 정보처리학회논문지C
• /
• 제9C권6호
• /
• pp.945-952
• /
• 2002

For a successful inter-system handoff, several important issues must be handled and additional new features must be considered. This paper focuses on the cellular structure of small cells which are required for the high density of population and a handoff scheme designed between two heterogenous networks. Incase of inter-system handoff (ISHO), the time required to complete the handoff can vary and depends on the structure of networks. And also the transmission of additional signals can increase the probability of failure for ISHO. Here we propose the sub-boundary cell base station (Sub-BBS) to alleviate the role of the BBS. The Sub-BBS is adjacent to BBS in the same regional mobile network. 쪼en the mobile terminal enters Sub-BBS, the network starts finding a new route and after entering BBS, it initiates the transformation process. The proposed scheme significantly reduces the ISHO failure rate compared to the existing one which is the most recent and known as efficient.

• IMMUNE NETWORK
• /
• 제4권3호
• /
• pp.184-189
• /
• 2004

Background: Hu syndrome, a neurological disorder, is characterized by the remote effect of small cell lung cancer on the neural degeneration. The suspicious effectors for this disease are anti-Hu autoantibodies or Hu-related CD8+ T lymphocytes. Interestingly, the same effectors have been suggested to act against tumor growth and this phenomenon may represent natural tumor immunity. For these diagnostic and therapeutic reasons, the demand for antibodies against Hu protein is rapidly growing. Methods: Polyclonal and monoclonal antibodies were generated using recombinant HuR protein. Western blot analyses were performed to check the specificity of generated antibodies using various recombinant proteins and cell lysates. Extracellular stimuli for HuR expression had been searched and HuR-associated proteins were isolated from polysome lysates and then separated in a 2-dimensional gel. Results: Polyclonal and monoclonal antibodies against HuR protein were generated and these antibodies showed HuR specificity. Antibodies were also useful to detect and immunoprecipitate endogenous HuR protein in Jurkat and BJAB. This report also revealed that TNF-${\alpha}$ treatment in BJAB up-regulated HuR expression. Lastly, protein profile in HuR-associated mRNAprotein complexes was mapped by 2-dimensional gel electrophoresis. Conclusion: This study reported that new antibodies against HuR protein were successfully generated. Currently, project to develop a diagnostic kit is in process. Also, this report showed that TNF-${\alpha}$ up-regulated HuR expression in BJAB and protein profile associated with HuR protein was mapped.

• Applied Microscopy
• /
• 제25권2호
• /
• pp.11-19
• /
• 1995

This research was undertaken to determine the effect of cyclophosphamide(CP) on the Leydig cells and macrophages in the interstitial tissue of the mice(ICR strain). To evaluate how this drug could affect the these cells, during administration(200mg/kg) 1 time to 3 times at intervals of 48hrs. In the Leydig cells of the control and 1 time treated group, a number of microperoxisomes were observed interspersed among the network of smooth endoplasmic reticulum(SER) in cellular regions where the SER predominantes. Microperoxisomes were also founded in close proximity to the cell membrane. The interstitial tissue were exhibited degenerating Leydig cells but macrophages wer containd greatly increased numbers of cytoplasmic inclusion body and secondary lysosomes. In the 1 time treated group. A very small number of Leydig cells were observed, from 2 to 3 time group, but macrophages were more increased than 1 time group in number. CP thus offers a valuable opportunity to study further the interaction between Leydig cells and macrophages in the interstitial tissue. These alteration could be direct mediated by toxic effect of the drug on the interstitial tissue.

• 전기학회논문지P
• /
• 제64권4호
• /
• pp.231-235
• /
• 2015

Bimodal Tram developed by KRRI is driven by a series Hybrid propulsion system which has both the CNG engine, generator and LPB(Lithium Polymer Battery) pack. It has three driving modes; Hybrid mode, Engine mode and Battery mode. Even in case of Battery mode, LPB pack to get enough power to drive the vehicle only by itself onsists of 168 LPB cells(80Ah per lcell), 650V. It is important thing to manage LPB pack in a right way, which will extend the lifetime of LPB cells and operate in the hybrid mode effectively. This paper has shown the development of battery management system(12 BMS, 1 BMS per 14cells) to manage LPB pack which is connected with CAN(Controller Area Network) each other and measure the voltage, current, temperature and also control the cooling fan inside of LPB pack. Using the measured data, BMS can show the SOC(State of Charge), SOH(State of Health) and other status of LPB pack including of the cell balancing.