• Title/Summary/Keyword: Overcome Factors

Search Result 1,027, Processing Time 0.023 seconds

Comparative Evaluation for Seasonal CO2 Flows Tracked by GOSAT in Northeast Asia (GOSAT으로 추적된 동북아시아 이산화탄소 유동방향의 계절별 비교평가)

  • Choi, Jin Ho;Um, Jung-Sup
    • Spatial Information Research
    • /
    • v.20 no.5
    • /
    • pp.1-13
    • /
    • 2012
  • This study intends to evaluate the seasonal flow direction of carbon dioxide in Northeast Asia by using GOSAT, the first Greenhouse Observing SATellite, in an attempt to overcome costly, laborious and time consuming ground observation which has been frequently pointed out in existing studies. For this purpose, missing values were supplemented by applying the Kriging interpolation and the overall flow direction of carbon dioxide was determined through anisotoropy semi-variogram. As a result, it was found that the overall spatial distribution of carbon dioxide in Northeast Asia varies depending on the latitude, and that carbon dioxide mainly flows southeast or east in spring, autumn and winter, but northeast or north in summer. Similar to the flow of monsoons in Northeast Asia, these results show that carbon dioxide flows mainly from the west to the east, which proves that carbon dioxide discharged from China is influencing even the Korean Peninsula and Japan. However, as the flow of carbon dioxide varies depending on a variety of factors such as artificial sources, plant respiration, and the absorption and discharge of the ocean, follow-up studies are requested to evaluate such variables and the correlations.

Angiogenesis and vasculogenic mimicry as therapeutic targets in ovarian cancer

  • Lim, Dansaem;Do, Yeojin;Kwon, Byung Su;Chang, Woochul;Lee, Myeong-Sok;Kim, Jongmin;Cho, Jin Gu
    • BMB Reports
    • /
    • v.53 no.6
    • /
    • pp.291-298
    • /
    • 2020
  • Tumor angiogenesis is an essential process for growth and metastasis of cancer cells as it supplies tumors with oxygen and nutrients. During tumor angiogenesis, many pro-angiogenic factors are secreted by tumor cells to induce their own vascularization via activation of pre-existing host endothelium. However, accumulating evidence suggests that vasculogenic mimicry (VM) is a key alternative mechanism for tumor vascularization when tumors are faced with insufficient supply of oxygen and nutrients. VM is a tumor vascularization mechanism in which tumors create a blood supply system, in contrast to tumor angiogenesis mechanisms that depend on pre-existing host endothelium. VM is closely associated with tumor progression and poor prognosis in many cancers. Therefore, inhibition of VM may be a promising therapeutic strategy and may overcome the limitations of anti-angiogenesis therapy for cancer patients. In this review, we provide an overview of the current anti-angiogenic therapies for ovarian cancer and the current state of knowledge regarding the links between microRNAs and the VM process, with a focus on the mechanism that regulates associated signaling pathways in ovarian cancer. Moreover, we discuss the potential for VM as a therapeutic strategy against ovarian cancer.

Preliminary study on car detection and tracking method using surveillance camera in tunnel environment for accident detection (터널 내 유고상황 자동 판정을 위한 선행 연구: CCTV를 이용한 차량의 탐지와 추적 기법 고찰)

  • Oh, Young-Sup;Shin, Hyu-Soung
    • Journal of Korean Tunnelling and Underground Space Association
    • /
    • v.19 no.5
    • /
    • pp.813-827
    • /
    • 2017
  • Surveillance cameras installed in tunnels capture the various video frames effected by dynamic and variable factors. In addition, localizing and managing the cameras in tunnel is not affordable, and quality of capturing frame is effected by time. In this paper, we introduce a new method to detect and track the vehicles in tunnel by using surveillance cameras installed in a tunnel. It is difficult to detect the video frames directly from surveillance cameras due to the motion blur effect and blurring effect on lens by dirt. In order to overcome this difficulties, two new methods such as Differential Frame/Non-Maxima Suppression (DFNMS) and Haar Cascade Detector to track cars are proposed and investigated for their feasibilities. In the study, it was shown that high precision and recall values could be achieved by the two methods, which then be capable of providing practical data and key information to an automatic accident detection system in tunnels.

A Grounded-theory Approach to the Process of Life Adaptation in Women with Cervical Cancer (자궁경부암 여성의 삶의 적응에 관한 근거이론적 접근)

  • Lee, Sook-Hee;Kim, Jeung-Im;Lee, Hae-Kyung;Kang, Nam-Mi;Kim, Hae-Won;Lee, Eun-Hee;Hur, Myung-Haeng;Park, Young-Sook
    • Women's Health Nursing
    • /
    • v.10 no.1
    • /
    • pp.32-41
    • /
    • 2004
  • Purpose: The purpose of this study was to explore and describe the process of life adaptation in women with cervical cancer. Method: A grounded theory method with guided data collection and analysis was used. Fifteen women with cervical cancer who had some kind of treatment at the hospital were asked open-ended and descriptive questions with a guideline. All interviews were tape-recorded and transcribed verbatim. Result: The core category that emerged from the comparative analysis was "overcoming cancer" named as a process of life adaptation in the participants. The process of overcoming cancer evolved three stages - "admitting reality", "attempting health-care" and "continuing health-care". Depending on the paradigm model, the central phenomena of the experiences was "powerlessness". The internal factors motivating women to overcome cancer were "denial of cancer" and "desire for life". Strategies of overcoming cancer included "living as a cancer patient," "selective food eating," "steady exercising," "getting rid of stress," and "preparing for death". The intervening conditions, "supportive system," "forms of life," and "burden on family," influenced overcoming cancer. Conclusion: The results of this study could help clinical nurses to understand life adaptation in cervical cancer patients and establish efficient coping strategies in dealing with the problems they face.

  • PDF

A New Metric for Evaluation of Forecasting Methods : Weighted Absolute and Cumulative Forecast Error (수요 예측 평가를 위한 가중절대누적오차지표의 개발)

  • Choi, Dea-Il;Ok, Chang-Soo
    • Journal of Korean Society of Industrial and Systems Engineering
    • /
    • v.38 no.3
    • /
    • pp.159-168
    • /
    • 2015
  • Aggregate Production Planning determines levels of production, human resources, inventory to maximize company's profits and fulfill customer's demands based on demand forecasts. Since performance of aggregate production planning heavily depends on accuracy of given forecasting demands, choosing an accurate forecasting method should be antecedent for achieving a good aggregate production planning. Generally, typical forecasting error metrics such as MSE (Mean Squared Error), MAD (Mean Absolute Deviation), MAPE (Mean Absolute Percentage Error), and CFE (Cumulated Forecast Error) are utilized to choose a proper forecasting method for an aggregate production planning. However, these metrics are designed only to measure a difference between real and forecast demands and they are not able to consider any results such as increasing cost or decreasing profit caused by forecasting error. Consequently, the traditional metrics fail to give enough explanation to select a good forecasting method in aggregate production planning. To overcome this limitation of typical metrics for forecasting method this study suggests a new metric, WACFE (Weighted Absolute and Cumulative Forecast Error), to evaluate forecasting methods. Basically, the WACFE is designed to consider not only forecasting errors but also costs which the errors might cause in for Aggregate Production Planning. The WACFE is a product sum of cumulative forecasting error and weight factors for backorder and inventory costs. We demonstrate the effectiveness of the proposed metric by conducting intensive experiments with demand data sets from M3-competition. Finally, we showed that the WACFE provides a higher correlation with the total cost than other metrics and, consequently, is a better performance in selection of forecasting methods for aggregate production planning.

Nonlinear soil parameter effects on dynamic embedment of offshore pipeline on soft clay

  • Yu, Su Young;Choi, Han Suk;Lee, Seung Keon;Park, Kyu-Sik;Kim, Do Kyun
    • International Journal of Naval Architecture and Ocean Engineering
    • /
    • v.7 no.2
    • /
    • pp.227-243
    • /
    • 2015
  • In this paper, the effects of nonlinear soft clay on dynamic embedment of offshore pipeline were investigated. Seabed embedment by pipe-soil interactions has impacts on the structural boundary conditions for various subsea structures such as pipeline, riser, pile, and many other systems. A number of studies have been performed to estimate real soil behavior, but their estimation of seabed embedment has not been fully identified and there are still many uncertainties. In this regards, comparison of embedment between field survey and existing empirical models has been performed to identify uncertainties and investigate the effect of nonlinear soil parameter on dynamic embedment. From the comparison, it is found that the dynamic embedment with installation effects based on nonlinear soil model have an influence on seabed embedment. Therefore, the pipe embedment under dynamic condition by nonlinear parameters of soil models was investigated by Dynamic Embedment Factor (DEF) concept, which is defined as the ratio of the dynamic and static embedment of pipeline, in order to overcome the gap between field embedment and currently used empirical and numerical formula. Although DEF through various researches is suggested, its range is too wide and it does not consider dynamic laying effect. It is difficult to find critical parameters that are affecting to the embedment result. Therefore, the study on dynamic embedment factor by soft clay parameters of nonlinear soil model was conducted and the sensitivity analyses about parameters of nonlinear soil model were performed as well. The tendency on dynamic embedment factor was found by conducting numerical analyses using OrcaFlex software. It is found that DEF was influenced by shear strength gradient than other factors. The obtained results will be useful to understand the pipe embedment on soft clay seabed for applying offshore pipeline designs such as on-bottom stability and free span analyses.

Simultaneous Inhibition of CXCR4 and VLA-4 Exhibits Combinatorial Effect in Overcoming Stroma-Mediated Chemotherapy Resistance in Mantle Cell Lymphoma Cells

  • Kim, Yu-Ri;Eom, Ki-Seong
    • IMMUNE NETWORK
    • /
    • v.14 no.6
    • /
    • pp.296-306
    • /
    • 2014
  • There is growing evidence that crosstalk between mantle cell lymphoma (MCL) cells and stromal microenvironments, such as bone marrow and secondary lymphoid tissues, promotes tumor progression by enhancing survival and growth as well as drug resistance of MCL cells. Recent advances in the understanding of lymphoma microenvironment have led to the identification of crucial factors involved in the crosstalk and subsequent generation of their targeted agents. In the present study, we evaluated the combinatory effect of blocking antibodies (Ab) targeting CXCR4 and VLA-4, both of which were known to play significant roles in the induction of environment-mediated drug resistance (EMDR) in MCL cell line, Jeko-1. Simultaneous treatment with anti-CXCR4 and anti-VLA-4 Ab not only reduced the migration of Jeko-1 cells into the protective stromal cells, but also enhanced sensitivity of Jeko-1 to a chemotherapeutic agent to a greater degree than with either Ab alone. These combinatorial effects were associated with decreased phosphorylation of ERK1/2, AKT and NF-${\kappa}B$. Importantly, drug resistance could not be overcome once the adhesion of Jeko-1 to the stromal occurred despite the combined use of Abs, suggesting that the efforts to mitigate migration of MCLs should be attempted as much as possible. Our results provide a basis for a future development of therapeutic strategies targeting both CXCR4 and VLA-4, such as Ab combinations or bispecific antibodies, to improve treatment outcomes of MCL with grave prognosis.

The Management Strategy of Network Competitiveness by Korean Enterprises in local Turkey (터키 현지 진출 한국 기업의 네트워크 경쟁 전략)

  • Bae, Kyung-Won;Park, Myung-Chan
    • International Commerce and Information Review
    • /
    • v.13 no.4
    • /
    • pp.101-124
    • /
    • 2011
  • This paper is framed for analyzing what the most significant factors are in Turkey, where the Korean investing enterprises should overcome and accomodate to the various barriers of management, especially in terms of network construction. The main purpose of this research is to test empirically some connections of between the managing strategy of network competitiveness by Korean enterprises and the management performances of Korean ones in Turkey while this is composed of two stages. First, the study model is planned by discussing relevant theories, previous studies and the current investment circumstances in local Turkey. Second, the survey of Korean enterprises participated in investment activities in there is practiced by gathering questionnaires. The strategic method of structural equation modeling is implemented to testing some hypotheses. Summing up partially, to maximize profits growth, Korean enterprises have been making application of the internal worker controlling as the means of network competitive advantages.

  • PDF

Indoor Positioning Using the WLAN-based Wavelet and Neural Network (WLAN 기반의 웨이블릿과 신경망을 이용한 위치인식 방법)

  • Kim, Jong-Bae
    • Journal of the Institute of Electronics Engineers of Korea CI
    • /
    • v.45 no.5
    • /
    • pp.38-47
    • /
    • 2008
  • The most commonly used location recognition system is the GPS-based approach. However, the GPS is inefficient for an indoor or urban area where high buildings shield the satellite signals. To overcome this problem, this paper propose the indoor positioning method using wavelet and neural network. The basic idea of proposed method is estimated the location using the received signal strength from wireless APs installed in the indoor environment. Because of the received signal strength of wireless radio signal is fluctuated by the environment factors, a feature that is strength of signal noise and error and express the time and frequency domain is need. Therefore, this paper is used the wavelet coefficient as the feature. And the neural network is used for estimate the location. The experiment results indicate 94.6% an location recognition rate.

Walking Environment Survey for Development of Specification on Personal Mobility (PM) Device for Elderly (고령자용 개인교통수단 개발 사양 정의를 위한 보행환경 조사)

  • Kim, Youngmin;Kim, Jisoo;Moon, Byeongsup
    • The Journal of The Korea Institute of Intelligent Transport Systems
    • /
    • v.16 no.6
    • /
    • pp.156-168
    • /
    • 2017
  • Personal mobility (PM) can increase the mobility of individual, so that the elderly can be set as the target group for using PM because of relatively low walking ability to normal. In this study, we design PM device for elderly that can be used safely in the walking environment such as sidewalk. There are various obstacles in the walking environment, so the device must have mechanical performance to overcome all of them. In this study, we survey the status and level of obstacle factors in walking environment to determine the dynamic performance of the PM device for elderly. We check up several guidelines about walking facilities to define obstacle points for the device, establish field survey methodologies, and conduct field survey for some specific road sections. Based on the survey results, we confirm the possible problems that could arise when the dynamic performance of the device is selected based on the facility-related criteria. We also define the performance requirements for the device based on the requirements for electric wheelchair.