• Title/Summary/Keyword: selective activation

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Ion Migration in Metal Halide Perovskites

  • Nur'aini, Anafi;Lee, Seokwon;Oh, Ilwhan
    • Journal of Electrochemical Science and Technology
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    • v.13 no.1
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    • pp.71-77
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    • 2022
  • Metal halide perovskites are promising photovoltaic materials, but they still have some issues that need to be solved. Hysteresis is a phenomenon that strongly is correlated with ion migration; thus, a fast, easy, and low-temperature method for measuring ion migration is required. Through selective blocking, ion migration can be measured separately, apart from electron migration. In this study, ion migration in metal halide perovskites was measured using a vertical device. At different temperatures, ionic activation energies were obtained for a range of perovskite compositions such as MAPbI3, FAPbI3, CsPbI3, and MAPbBr3. By comparing the measured ionic activation energies with the theoretical values, we conclude that among other possibilities, I- is the migrating ion in MAPbI3, FAPbI3, CsPbI3, and Br- is the migrating in MAPbBr3.

Expanded Object Localization Learning Data Generation Using CAM and Selective Search and Its Retraining to Improve WSOL Performance (CAM과 Selective Search를 이용한 확장된 객체 지역화 학습데이터 생성 및 이의 재학습을 통한 WSOL 성능 개선)

  • Go, Sooyeon;Choi, Yeongwoo
    • KIPS Transactions on Software and Data Engineering
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    • v.10 no.9
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    • pp.349-358
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    • 2021
  • Recently, a method of finding the attention area or localization area for an object of an image using CAM (Class Activation Map)[1] has been variously carried out as a study of WSOL (Weakly Supervised Object Localization). The attention area extraction from the object heat map using CAM has a disadvantage in that it cannot find the entire area of the object by focusing mainly on the part where the features are most concentrated in the object. To improve this, using CAM and Selective Search[6] together, we first expand the attention area in the heat map, and a Gaussian smoothing is applied to the extended area to generate retraining data. Finally we train the data to expand the attention area of the objects. The proposed method requires retraining only once, and the search time to find an localization area is greatly reduced since the selective search is not needed in this stage. Through the experiment, the attention area was expanded from the existing CAM heat maps, and in the calculation of IOU (Intersection of Union) with the ground truth for the bounding box of the expanded attention area, about 58% was improved compared to the existing CAM.

Removal of Iron from Ilmenite through Selective Chlorination Using PVC (PVC에 의한 일메나이트 광석 중 선택염화에 의한 Fe의 제거)

  • Son, Yongik;Ring, Rie;Sohn, Ho-Sang
    • Resources Recycling
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    • v.25 no.3
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    • pp.74-81
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    • 2016
  • Study on chlorination of ilmenite ore were carried out by using PVC(polyvinyl chloride) as the chlorinating agent in a static bed reactor for selective removal of iron. The effect of amount of PVC and reaction temperature were investigated. It was found that the removal ratio of iron increased with amount of PVC and temperature. After reaction with HCl gas generated from PVC, porous surface of the specimens were observed. As a result, HCl gas could react with iron in the central portion of ilmenite particle through these pores. Examination of data using kinetic model suggest that the selective chlorination rate is controlled by chemical reaction at the interface of particles. The activation energy for the selective chlorination of ilmenite using PVC was calculated as 20.47 kJ/mol.

The Inhibitory Effect of Opioid on the Hyperpolarization-Activated Cation Currents in Rat Substantia Gelatinosa Neurons

  • Seol, Geun-Hee;Kim, Jun;Cho, Sun-Hee;Kim, Won-Ki;Kim, Jong-Whan;Kim, Sang-Jeong
    • The Korean Journal of Physiology and Pharmacology
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    • v.5 no.5
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    • pp.373-380
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    • 2001
  • The action of opioid on the hyperpolarization-activated cation current $(I_h)$ in substantia gelatinosa neurons were investigated by using whole-cell voltage-clamp recording in rat spinal brain slices. Hyperpolarizing voltage steps revealed slowly activating currents in a subgroup of neurons. The half-maximal activation and the reversal potential of the current were compatible to neuronal $I_h.$ DAMGO $(1\;{\mu}M),$ a selective- opioid agonist, reduced the amplitude of $I_h$ reversibly. This reduction was dose-dependent and was blocked by CTOP $(2\;{\mu}M),$ a selective ${\mu}-opioid$ antagonist. DAMGO shifted the voltage dependence of activation to more hyperpolarized potential. Cesium (1 mM) or ZD 7288 $(100\;{\mu}M)$ blocked $I_h$ and the currents inhibited by cesium, ZD 7288 and DAMGO shared a similar time and voltage dependence. These results suggest that activation of ${\mu}-opioid$ receptor by DAMGO can inhibit $I_h$ in a subgroup of rat substantia gelatinosa neurons.

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Selective Contact Hole Filling by electroless Ni Plating (무전해 Ni 도금에 의한 선택적 CONTACT HOLE 충전)

  • 우찬희;권용환;김영기;박종완;이원해
    • Journal of the Korean institute of surface engineering
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    • v.25 no.4
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    • pp.189-206
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    • 1992
  • The effect of activation and electroless nickel plating conditions on contact properties was investi-gated for selective electroless nickel plating of Si wafers in order to obtain an optimum condition of con-tact hole filling. According to RCA prosess, p-type silicon (100) surface was cleaned out and activated. The effects of temperature, DMAB concentration, time, and strirring were investigated for activation of p-type Si(100) surface. The optimal activation condition was 0.2M HF, 1mM PdCl2, 2mM EDTA,$ 70^{\circ}C$, and 90sec under ultrasonic vibration. In electroless nickel plating, the effect of temperature, DMAB concentra-tion, pH, and plating time were studied. The optimal plating condition found was 0.10M NiSO4.H2O, 0.11M Citrate, pH 6.8, $60^{\circ}C$, 30minutes. The contact resistance of films was comparatively low. It took 30minutes to obtain 1$\mu\textrm{m}$ thick film with 8mM DMAB concentration. The film surface roughness was improved with decreasing temperature and decreasing pH of the plating solution. The best quality of the film was obtained at the condition of temperature $60^{\circ}C$ and pH 6.0. The micro-vickers hardness of film was about 800Hv. Plating rate of nickel on the hole pattern was slower than that of nickel on the line pattern.

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Effects of the Additional Scapular Posterior Tilt Movement on Selective Muscle Activation of the Lower Trapezius during Prone Shoulder Extension

  • Kim, Sooyong;Kang, Minhyeok
    • Journal of International Academy of Physical Therapy Research
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    • v.12 no.2
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    • pp.2308-2313
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    • 2021
  • Background: Although the scapular posterior tilt movement could facilitate the lower trapezius (LT) muscle activity, no study identified the effects of the scapular posterior tilt movement on the selective activation of the LT muscle during prone shoulder extension. Objectives: To examine the influences of additional scapular posterior tilt on electromyography (EMG) of the upper trapezius (UT) and the LT muscles during prone shoulder extension. Design: Cross-sectional study. Methods: There were 15 asymptomatic male participants in this study who performed prone shoulder extension with and without scapular posterior tilt movements. For the scapular posterior tilt movements, participants performed visual biofeedback training for scapular movement using motion sensor. During the exercises, the EMG activity of the UT and LT was recorded using surface EMG system. Results: The EMG activity of the LT significantly increased during prone shoulder extension with scapular posterior tilt compared to that of general prone shoulder extension, whereas that of the UT was not significantly different between the two exercises. Moreover, scapular posterior tilt application significantly decreased UT/LT muscle activity ratio. Conclusion: Scapular posterior tilt movement may be emphasized during exercise when facilitating LT muscle activation.

Mitophagy: a balance regulator of NLRP3 inflammasome activation

  • Kim, Min-Ji;Yoon, Joo-Heon;Ryu, Ji-Hwan
    • BMB Reports
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    • v.49 no.10
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    • pp.529-535
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    • 2016
  • The NLRP3 inflammasome is activated by a variety of external or host-derived stimuli and its activation initiates an inflammatory response through caspase-1 activation, resulting in inflammatory cytokine IL-1β maturation and secretion. The NLRP3 inflammasome activation is a kind of innate immune response, most likely mediated by myeloid cells acting as a host defense mechanism. However, if this activation is not properly regulated, excessive inflammation induced by overactivated NLRP3 inflammasome can be detrimental to the host, causing tissue damage and organ dysfunction, eventually causing several diseases. Previous studies have suggested that mitochondrial damage may be a cause of NLRP3 inflammasome activation and autophagy, which is a conserved self-degradation process that negatively regulates NLRP3 inflammasome activation. Recently, mitochondria-selective autophagy, termed mitophagy, has emerged as a central player for maintaining mitochondrial homeostasis through the elimination of damaged mitochondria, leading to the prevention of hyperinflammation triggered by NLRP3 inflammasome activation. In this review, we will first focus on the molecular mechanisms of NLRP3 inflammasome activation and NLRP3 inflammasome-related diseases. We will then discuss autophagy, especially mitophagy, as a negative regulator of NLPP3 inflammasome activation by examining recent advances in research.

A Robust Continuous Object Tracking Protocol Using Chained Selective Wakeup Strategy in Wireless Sensor Networks (무선 센서 네트워크에서 연결된 선택적 활성화 기법을 사용하는 강건한 연속 객체 추적 프로토콜)

  • Hong, Hyungseop;Kim, Sang-Ha
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.38B no.1
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    • pp.72-79
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    • 2013
  • In wireless sensor networks, the selective wakeup scheme is one of the energy saving mechanisms, that is used for an object detecting or tracking. Recently, many protocols are proposed using the selective wakeup scheme for the continuous objects tracking such as forest fires and poison gas. They predict the future shape of continuous objects and activate only sensors in the predicted boundary area of the objects. It works correctly in a uniformly deployed wireless sensor networks. However, it cannot be directly applied to a randomly deployed sensor networks with voids. When the predicted area is in the void area, the activation message cannot reach and the predicted area cannot be activated at the right time. It leads to many detection errors for continuous object. Moreover, if a sensor is once foiled in a activation control then the next activation control might be continuously failed. The detection errors can be result in serious harm to people. In this paper, we propose a chaining selective wakeup scheme for robust continuous object tracking in wireless sensor networks. In our protocol, we collect the information of a void area during the network configuration time; if the next boundary area is in the void area, we activate the chained area surrounding the void area with activation control message.

DEPRENYL INHIBITS POTENTIATED ARSENIC-INDUCED CYTOTOXICITY VIA THE INHIBITION OF C-JUN N- TERMINAL KINASE ACTIVATION

  • Park, Jeong-Weon;Kim, Sang-Geon
    • Proceedings of the Korean Society of Toxicology Conference
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    • 2001.10a
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    • pp.147-147
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    • 2001
  • A previous study showed that sulfur amino acid deprivation (SAAD) potentiated cytotoxicity induced by arsenic (As) and that activation of ERKl/2, p38 kinase and JNK1 was responsible for the potentiation of As toxicity. In the present study, we found for the first time that deprenyl a selective monoamine oxidase B inhibitor prevented potentiation of As toxicity by SAAD in a dose-dependent manner.(omitted)

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Area selective atomic layer deposition via surface reaction engineering: a review (표면 반응 제어를 통한 영역 선택적 원자층 증착법 연구 동향)

  • Ko, Eun-Chong;Ahn, Ji Sang;Han, Jeong Hwan
    • Journal of the Korean institute of surface engineering
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    • v.55 no.6
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    • pp.328-341
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    • 2022
  • Area selective atomic layer deposition (AS-ALD) is a bottom-up nanopattern fabrication method that can grow the ALD films only on the desired substrate areas without using photolithography and etching processes. Particularly, AS-ALD has attracted great attention in the semiconductor manufacturing process due to its advantage in reducing edge placement error by fabricating self-aligned patterns. In this paper, the basic principles and characteristics of AS-ALD are described. In addition, various approaches for achieving AS-ALD with excellent selectivity were comprehensively reviewed. Finally, the technology development to overcome the selectivity limit of AS-ALD was introduced along with future prospects.