• 제목/요약/키워드: further study

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Rapid Surface Heating Promotes Laser Desorption Ionization of Thermally Labile Molecules from Surfaces

  • Han, Sang Yun
    • Mass Spectrometry Letters
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    • 제7권4호
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    • pp.91-95
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    • 2016
  • In recent years, matrix-free laser desorption ionization (LDI) for mass spectrometry of thermally labile molecules has been an important research subject in the pursuit of new ionization methods to serve as alternatives to the conventional matrix-assisted laser desorption ionization (MALDI) method. While many recent studies have reported successful LDI of thermally labile molecules from various surfaces, mostly from surfaces with nanostructures, understanding of what drives the LDI process still requires further study. This article briefly reviews the thermal aspects involved in the LDI mechanism, which can be characterized as rapid surface heating. The thermal mechanism was supported by observed LDI and postsource decay (PSD) of peptide ions produced from flat surfaces with special thermal properties including amorphous Si (a-Si) and tungsten silicide ($WSi_x$). In addition, the concept of rapid surface heating further suggests a practical strategy for the preparation of LDI sample plates, which allows us to choose various surface materials including crystalline Si (c-Si) and Au tailorable to specific applications.

산업용 위험기계·기구 의무 및 임의 안전인증의 효과 및 균형 (Effectiveness and Balance of Compulsory and Voluntary Safety Certification of Industrial Machines and Devices)

  • 최기흥
    • 한국안전학회지
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    • 제31권1호
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    • pp.7-12
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    • 2016
  • This study first focuses on the quantitative evaluation of both compulsory and voluntary safety certification of industrial machines and devices. Based on the results of statistical analysis, effectiveness of those safety certifications were confirmed. In order to reduce both the frequency and the strength of industrial accidents associated with industrial machines and devices, major target of safety regulations needs to be shifted from users to manufacturers. Adjustment of industrial machines and devices which are subject to compulsory safety certification and implementation of risk assessment are further suggested. As for the voluntary certification, reestablishment of the concept of voluntary safety certification and balance between compulsory and voluntary certifications is discussed. Voluntary safety certification is further suggested as a mean to manage safety of industrial machines and devices which are not subject to any safety regulations.

DYNAMIC BEHAVIOUR FOR A NONAUTONOMOUS SMOKING DYNAMICAL MODEL WITH DISTRIBUTED TIME DELAY

  • Samanta, G.P.
    • Journal of applied mathematics & informatics
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    • 제29권3_4호
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    • pp.721-741
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    • 2011
  • In this paper we have considered a dynamical mathematical model of the sub-populations of potential smokers (non-smokers), smokers, smokers who temporarily quit smoking, smokers who permanently quit smoking and a class of smoking associated illness by introducing time dependent parameters and distributed time delay to acquire smoking habit. Here, we have established some sufficient conditions on the permanence and extinction of the smoking class in the community by using inequality analytical technique. We have introduced some new threshold values $R_0$ and $R^*$ and further obtained that the smoking class in the community will be permanent when $R_0$ > 1 and the smoking class in the community will be going to extinct when $R^*$ < 1. By Lyapunov functional method, we have also obtained some sufficient conditions for global asymptotic stability of this model. Computer simulations are carried out to explain the analytical findings. The aim of the analysis of this model is to identify the parameters of interest for further study, with a view to informing and assisting policy-maker in targeting prevention and treatment resources for maximum effectiveness.

Does Fake News Matter to Election Outcomes? The Case Study of Taiwan's 2018 Local Elections

  • Wang, Tai-Li
    • Asian Journal for Public Opinion Research
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    • 제8권2호
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    • pp.67-104
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    • 2020
  • Fake news and disinformation provoked heated arguments during Taiwan's 2018 local election. Most significantly, concerns grew that Beijing was attempting to sway the island's politics armed with a new "Russian-style influence campaign" weapon (Horton, 2018). To investigate the speculated effects of the "onslaught of misinformation," an online survey with 1068 randomly selected voters was conducted immediately after the election. Findings confirmed that false news affected Taiwanese voters' judgment of the news and their voting decisions. More than 50% of the voters cast their votes without knowing the correct campaign news. In particular, politically neutral voters, who were the least able to discern fake news, tended to vote for the China-friendly Kuomintang (KMT) candidates. Demographic analysis further revealed that female voters tended to be more likely to believe fake news during the election period compared to male voters. Younger or lower-income voters had the lowest levels of discernment of fake news. Further analyses and the implications of these findings for international societies are deliberated in the conclusion.

Online Flow: Effects of Perceived Challenges Measured Before and After a Shopping Task

  • Shim, Soo In;Kwon, Wi-Suk
    • Fashion, Industry and Education
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    • 제14권1호
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    • pp.10-17
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    • 2016
  • The purpose of this study is to examine the difference between perceived challenges measured before and after shopping online for fashion products and their effects in leading to flow. An online survey including an online shopping task was conducted with a national sample of 500 adult consumers recruited in the U.S.A. The paired t-test results show that perceived challenge measured before the task is significantly higher than perceived challenge measured after the task. ANOVA results further show that the interaction effect between skill and challenge on flow is significant only when perceived challenge is measured after that task. Implications of the findings and recommendations for further research are also discussed.

백색소음하에서 단어암기 및 재인검사 수행시의 경악 및 정향반사 특성 : 스트레스/정서연구에의 시사점 (STARTLE AND ORIENTING REFLEX COMPONENTS MODULATION BY ATTENTION TO TASK AND PERFORMANCE OF MENTAL TEST WITH NOISE FOREGROUND)

  • ;이임갑;박경진;손진훈
    • 한국감성과학회:학술대회논문집
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    • 한국감성과학회 1999년도 춘계학술발표논문집 논문집
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    • pp.139-145
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    • 1999
  • In current study on 8 college students there was examined modulation of eyeblink (as measured by integrated EMG of m.orbicularis oculi) and skin conductance response (SCR) to an acoustic startle probe (85 dB[A] white noise) by attending to task presented in auditory modality (to memorize words for further recognition) and entire performance of the word recognition test. Both eyeblink magnitude and SCR amplitude and rise time to startle probes were modified (larger magnitude of EMG peak, lower amplitude and shorter rise time of SCR) during attending to task as compared to performance on test. Results are interpreted n terms of modification of electrodermal and eyeblink components of startle and orienting reflexes by task characteristics (passive versus active efforts), attentional demands and aversiveness of experimental situation. However, eyeblink startle response manifested potentiation during attending to task, while SCR demonstrated attenuation. There are discussed implications of startle modulatioas a potentially sensitive probe of situational demands in stress research and also are considered prospects for further studies.

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Ab Initio Study of Mechanism of Forming Germanic Bis-Heterocyclic Compound between Dimethyl-Germylene Carbene (Me2Ge=C:) and Acetone

  • Lu, Xiuhui;Che, Xin;Lian, Zhenxia;Li, Yongqing
    • Bulletin of the Korean Chemical Society
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    • 제32권1호
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    • pp.89-94
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    • 2011
  • The mechanism of the cycloaddition reaction of forming germanic bis-heterocyclic compound between singlet dimethylgermylene carbene and acetone has been investigated with CCSD(T)//B3LYP/6-$31G^*$ method. From the potential energy profile, it can be predicted that, this reaction has one dominant channel. The presented rule of this dominant channel is that the two reactants firstly form a four-membered ring carbene (RC4) through the [2+2] cycloaddition reaction. Due to $sp^2$ hybridization of carbene C atom in RC4, RC4 further combines with acetone to form a reactant complexe (RC5). Due to the further $sp^3$ hybridization of carbene C atom in RC4, RC5 isomerizes to a germanic bisheterocyclic compound (P6) via the transition state (TS5).

Homology Modeling of GPR18 Receptor, an Orphan G-protein-coupled Receptor

  • Kothandan, Gugan;Cho, Seung Joo
    • 통합자연과학논문집
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    • 제6권1호
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    • pp.16-20
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    • 2013
  • G-protein-coupled receptor (GPCR) superfamily is the largest known receptor family, characterized by seven transmembrane domains and considered to be an important drug target. In this study we focused on an orphan GPCR termed as GPR18. As there is no X-ray crystal structure has been reported for this receptor, we report on a homology model of GPR18. Template structure with high homology was used for modeling and ten models were developed. A model was selected and refined by energy minimization. The selected model was further validated using various parameters. Our results could be a starting point for further structure based drug design.

THE NUMERICAL SIMULATION OF ASTRO-CLIMATE CONDITIONS OVER THE TIBETAN PLATEAU

  • QIAN, XUAN;YAO, YONGQIANG;WANG, HONGSHUAI;LIU, LIYONG
    • 천문학논총
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    • 제30권2호
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    • pp.695-697
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    • 2015
  • The wind field and precipitable water vapor over the Tibetan Plateau are analyzed using the numerical model WRF. The spatial and vertical distributions of the relevant meteorological factors are summarized, providing evidence for selecting and further evaluating an astronomical site. This study serves as a further demonstration towards astro-climate regionalization, and provides us with an essential database for an astronomical site survey over the Tibetan Plateau.

Stability Analysis of Soil Oribatid Mite Communities (Acari: Oribatida from Namsan and Kwangreung Deciduous Forests, Korea

  • Jung, Chulue;Lee, Joon-Ho
    • The Korean Journal of Ecology
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    • 제24권4호
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    • pp.239-243
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    • 2001
  • One of the most important justifications of conservation of ecosystem and biodiversity is that diversity begets stability. Impact of biodiversity on community and ecosystem function has long been debated in science. Here we report the stability analysis of soil oribatid mite communities from environmentally stressed habitat(Namsan) and relatively well preserved habitat (Kwangreung) with the perspective of consistency as a primary criteria of stability. Stability of oribatid mite communities were evaluated with turnover rate, constancy analysis, b diversity index, and absolute abundance, abundance ranking, and the presence or absence of species over time. Out of 6 criteria, three consented that oribatid community from Kwangreung was more stable than that from Namsan. Those are turnover rate in litter layer, constancy analysis, and absolute abundance. Feasibility of stability analysis using oribatid mites was further discussed, rendering further study.

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