• 제목/요약/키워드: Self-Potential

검색결과 1,448건 처리시간 0.026초

Self-Assembled Peptide Structures for Efficient Water Oxidation

  • Lee, Jae Hun;Lee, Jung Ho;Park, Yong Sun;Nam, Ki Tae
    • Proceedings of the Korean Vacuum Society Conference
    • /
    • 한국진공학회 2013년도 제45회 하계 정기학술대회 초록집
    • /
    • pp.280-280
    • /
    • 2013
  • In green plants, energy generation is accomplished through light-harvesting photosystem, which utilize abundant visible light and multi-stepwise redox reaction to oxidize water and reduce NADP+, transferring electrons efficiently with active cofactors1. Inspired by natural photosynthesis, artificial solar water-splitting devices are being designed variously. However, the several approaches involving immobilization2, conjugation3, and surface modification4 still have limitations. We have made artificial photosynthesis templates by self-assembling tyrosine-based peptide to mimick photosystem II. Porphyrin sensitizer absorbing blue light strongly was conjugated with the templates and they were hybridized with cobalt oxide through the reduction of cobalt ions in an aqueous solution. The formation of hybrid templates was characterized using TEM, and their water oxidation performance was measured by fluorescence oxygen probe. Our results suggest that the bio-templated assembly of functional compounds has a great potential for artificial photosynthesis.

  • PDF

Adversarial Wall: Physical Adversarial Attack on Cityscape Pretrained Segmentation Model (도시 환경에서의 이미지 분할 모델 대상 적대적 물리 공격 기법)

  • Suryanto, Naufal;Larasati, Harashta Tatimma;Kim, Yongsu;Kim, Howon
    • Proceedings of the Korea Information Processing Society Conference
    • /
    • 한국정보처리학회 2022년도 추계학술발표대회
    • /
    • pp.402-404
    • /
    • 2022
  • Recent research has shown that deep learning models are vulnerable to adversarial attacks not only in the digital but also in the physical domain. This becomes very critical for applications that have a very high safety concern, such as self-driving cars. In this study, we propose a physical adversarial attack technique for one of the common tasks in self-driving cars, namely segmentation of the urban scene. Our method can create a texture on a wall so that it can be misclassified as a road. The demonstration of the technique on a state-of-the-art cityscape pretrained model shows a fairly high success rate, which should raise awareness of more potential attacks in self-driving cars.

Self-expandable Metal Stents for Malignant Colorectal Obstruction (악성 대장 폐색에서의 자가팽창형 스텐트 삽입술)

  • Jae Jun Park
    • Journal of Digestive Cancer Research
    • /
    • 제12권1호
    • /
    • pp.15-22
    • /
    • 2024
  • Malignant colorectal obstructions urgently require decompression therapy to prevent the severe risks of intestinal ischemia and bowel perforation. In managing malignant colonic strictures endoscopically, the use of self-expandable metal stents (SEMS) is the predominant approach. Colonic SEMs are primarily used in preoperative decompression therapy before curative surgery and palliative treatment in patients with advanced disease stages. Furthermore, the stenting process, which requires rigorous clinical supervision, can lead to complications. This review endeavors to concisely review the clinical considerations associated with the SEMS procedure, with a focus on its indications, technical aspects, and potential complications that may arise during the procedure.

Theoretical Electronic Structure of PTCDA and PTCDI Molecules

  • Hyeon, Jeong-Min
    • Proceeding of EDISON Challenge
    • /
    • 제2회(2013년)
    • /
    • pp.221-223
    • /
    • 2013
  • Self-assembly of the molecular system of perylene-3,4,9,10-tetracarboxylic-3,4,9,10-dianhydride (PTCDA) and the amide analogue (PTCDI) is of potential importance for organic semiconductor devices. Therefore we studied the density of states (DOS), the charge densities, and intermolacular bond lengths for PTCDA and PTCDI using the density functional theory calculations.

  • PDF

MOSFET Model HiSIM Based on Surface-Potential Description for Enabling Accurate RF-CMOS Design

  • Miura-Mattausch, M.;Mattausch, H.J.;Ohguro, T.;Iizuka, T.;Taguchi, M.;Kumashiro, S.;Miyamoto, S.
    • JSTS:Journal of Semiconductor Technology and Science
    • /
    • 제4권3호
    • /
    • pp.133-140
    • /
    • 2004
  • The origin of the phenomena, obstructing circuit performance in the RF operating regime, as well as their modeling will be discussed. The applied surface-potential-based modeling allows self-consistent description of all phenomena important for accurate circuit simulation, as demonstrated with the MOSFET model HiSIM.

Studies on the Adsorption Modeling of Cationic Heavy Metals(Pb, Cd) by the Surface Complexation Model (Surface Complexation Model을 이용한 양이온 중금속(Pb, Cd) 흡착반응의 모델화 연구)

  • 신용일;박상원
    • Journal of Environmental Science International
    • /
    • 제8권2호
    • /
    • pp.211-219
    • /
    • 1999
  • Surface complexation models(SCMs) have been performed to predict metal ion adsorption behavior onto the mineral surface. Application of SCMs, however, requires a self-consistent approach to determine model parameter values. In this paper, in order to determine the metal ion adsorption parameters for the triple layer model(TLM) version of the SCM, we used the zeta potential data for Zeolite and Kaolinite, and the metal ion adsorption data for Pb(II) and Cd(II). Fitting parameters determined for the modeling were as follows ; total site concentration, site density, specific surface area, surface acidity constants, etc. Zeta potential as a new approach other than the acidic-alkalimetric titration method was adopted for simulation of adsorption phenomena. Some fitting parameters were determined by the trial and error method. Modeling approach was successful in quantitatively simulating adsorption behavior under various geochemical conditions.

  • PDF

Rate Proportional SCFQ Algorithm for High-Speed Packet-Switched Networks

  • Choi, Byung-Hwan;Park, Hong-Shik
    • ETRI Journal
    • /
    • 제22권3호
    • /
    • pp.1-9
    • /
    • 2000
  • Self-Clocked Fair Queueing (SCFQ) algorithm has been considered as an attractive packet scheduling algorithm because of its implementation simplicity, but it has unbounded delay property in some input traffic conditions. In this paper, we propose a Rate Proportional SCFQ (RP-SCFQ) algorithm which is a rate proportional version of SCFQ. If any fair queueing algorithm can be categorized into the rate proportional class and input is constrained by a leaky bucket, its delay is bounded and the same as that of Weighted Fair Queueing (WFQ) which is known as an optimal fair queueing algorithm. RP-SCFQ calculates the timestamps of packets arriving during the transmission of a packet using the current value of system potential updated at every packet departing instant and uses a starting potential when it updates the system potential. By doing so, RP-SCFQ can have the rate proportional property. RP-SCFQ is appropriate for high-speed packet-switched networks since its implementation complexity is low while it guarantees the bounded delay even in the worst-case input traffic conditions.

  • PDF

Psychosocial Predictors of Breast Self-Examination among Female Students in Malaysia: A Study to Assess the Roles of Body Image, Self-efficacy and Perceived Barriers

  • Ahmadian, Maryam;Carmack, Suzie;Samah, Asnarulkhadi Abu;Kreps, Gary;Saidu, Mohammed Bashir
    • Asian Pacific Journal of Cancer Prevention
    • /
    • 제17권3호
    • /
    • pp.1277-1284
    • /
    • 2016
  • Background: Early detection is a critical part of reducing the burden of breast cancer and breast self-examination (BSE) has been found to be an especially important early detection strategy in low and middle income countries such as Malaysia. Although reports indicate that Malaysian women report an increase in BSE activity in recent years, additional research is needed to explore factors that may help to increase this behavior among Southeastern Asian women. Objective: This study is the first of its kind to explore how the predicting variables of self-efficacy, perceived barriers, and body image factors correlate with self-reports of past BSE, and intention to conduct future breast self-exams among female students in Malaysia. Materials and Methods: Through the analysis of data collected from a prior study of female students from nine Malaysian universities (n=842), this study found that self-efficacy, perceived barriers and specific body image sub-constructs (MBSRQ-Appearance Scales) were correlated with, and at times predicted, both the likelihood of past BSE and the intention to conduct breast self-exams in the future. Results: Self-efficacy (SE) positively predicted the likelihood of past self-exam behavior, and intention to conduct future breast self-exams. Perceived barriers (BR) negatively predicted past behavior and future intention of breast self-exams. The body image sub-constructs of appearance evaluation (AE) and overweight preoccupation (OWP) predicted the likelihood of past behavior but did not predict intention for future behavior. Appearance orientation (AO) had a somewhat opposite effect: AO did not correlate with or predict past behavior but did correlate with intention to conduct breast self-exams in the future. The body image sub-constructs of body area satisfaction (BASS) and self-classified weight (SCW) showed no correlation with the subjects' past breast self-exam behavior nor with their intention to conduct breast self-exams in the future. Conclusions: Findings from this study indicate that both self-efficacy and perceived barriers to BSE are significant psychosocial factors that influence BSE behavior. These results suggest that health promotion interventions that help enhance self-efficacy and reduce perceived barriers have the potential to increase the intentions of Malaysian women to perform breast self-exams, which can promote early detection of breast cancers. Future research should evaluate targeted communication interventions for addressing self-efficacy and perceived barriers to breast self-exams with at-risk Malaysian women. and further explore the relationship between BSE and body image.

Electrical Responses on the Auriferous Mineralized Bone in Sambo Mine (삼보광산 금 광화대에 대한 전기탐사 반응)

  • You Youngjune;Yoo In-Kol;Kim Jung-Ho
    • Geophysics and Geophysical Exploration
    • /
    • 제7권4호
    • /
    • pp.217-224
    • /
    • 2004
  • Self-potential and electrical resistivity methods were conducted for locating the auriferous mineralized zone, called Jija Vein, of Sambo mine, Limsu-ri, Haeje-myeon, Muahn-gun, Jeollanam-do. The host rocks of the mineralization include gneiss, rhyolite and felsic dyke. Ore vein is mainly fissured-filling type and sulfide minerals, such as pyrite, are disseminated in country rock. By the electrical responses from SP and surface resistivity methods., the mineralized zone is supposed to extend about 360 m directed N5W with the width of 20 m to 30 m. From resistivity tomograms using inclined borehole to surface, the ore body shape is interpreted as the width of 20 m in depth 40 m to 50 m.

MicroRNA-203 As a Stemness Inhibitor of Glioblastoma Stem Cells

  • Deng, Yifan;Zhu, Gang;Luo, Honghai;Zhao, Shiguang
    • Molecules and Cells
    • /
    • 제39권8호
    • /
    • pp.619-624
    • /
    • 2016
  • Glioblastoma stem cells (GBM-SCs) are believed to be a subpopulation within all glioblastoma (GBM) cells that are in large part responsible for tumor growth and the high grade of therapeutic resistance that is so characteristic of GBM. MicroRNAs (miR) have been implicated in regulating the expression of oncogenes and tumor suppressor genes in cancer stem cells, including GBM-SCs, and they are a potential target for cancer therapy. In the current study, miR-203 expression was reduced in $CD133^+$ GBM-SCs derived from six human GBM biopsies. MicroRNA-203 transfected GBM-SCs had reduced capacity for self-renewal in the cell sphere assay and increased expression of glial and neuronal differentiation markers. In addition, a reduced proliferation rate and an increased rate of apoptosis were observed. Therefore, miR-203 has the potential to reduce features of stemness, specifically in GBM-SCs, and is a logical target for GBM gene therapy.