• Title/Summary/Keyword: feature hypothesis

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An Empirical Study on the Vendor's Opportunism in the Collaboration between Buyer and Vendor

  • Hwang, Sunil;Suh, Eung-Kyo
    • The Journal of Industrial Distribution & Business
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    • v.8 no.5
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    • pp.53-63
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    • 2017
  • Purpose - The main feature of this study is understanding of the vendor's opportunism on the collaboration context between buyer and vendor from the buyer's viewpoint with resource dependence theory. A number of studies on opportunism have focused on opportunistic definitions and its theoretical studies. Other researches emphasize the importance of governance in ways that reduce opportunism. We think that this research could be filled with the lack of previous studies. Research design, data, and methodology - In order to accomplish research purpose, four hypotheses have been established based on the framework of resource dependence theory and previous studies. And we have used 599 survey data jointly collected by Korea Productivity Center and the Ministry of Trade, Industry and Energy. To verify these hypothesis, we have conducted multiple regression analysis with SPSS 23.0. Results - The vendor 's opportunism decreases as mutual trust with buyer becomes higher. However, as the degree of dependence of buyers on vendor resources increases, vendor's opportunism increases. And monitoring vendor's capacity has a moderating effect with buyer resource dependency to vendor's opportunism. Conclusions - This study suggest there are two options to decrease vendor's opportunism. Increasing mutual trust or decrease dependence on vendor's resources. Also, monitoring suppler's capacity could be effective when vendor's resource dependence is high.

Polyadenylation-Dependent Translational Control of New Protein Synthesis at Activated Synapse

  • Shin Chan-Young;Yang Sung-Il;Kim Kyun-Hwan;Ko Kwang-Ho
    • Biomolecules & Therapeutics
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    • v.14 no.2
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    • pp.75-82
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    • 2006
  • Synaptic plasticity, which is a long lasting change in synaptic efficacy, underlies many neural processes like learning and memory. It has long been acknowledged that new protein synthesis is essential for both the expression of synaptic plasticity and memory formation and storage. Most of the research interests in this field have focused on the events regulating transcriptional activation of gene expression from the cell body and nucleus. Considering extremely differentiated structural feature of a neuron in CNS, a neuron should meet a formidable task to overcome spatial and temporal restraints to deliver newly synthesized proteins to specific activated synapses among thousands of others, which are sometimes several millimeters away from the cell body. Recent advances in synaptic neurobiology has found that almost all the machinery required for the new protein translation are localized inside or at least in the vicinity of postsynaptic compartments. These findings led to the hypothesis that dormant mRNAs are translationally activated locally at the activated synapse, which may enable rapid and delicate control of new protein synthesis at activated synapses. In this review, we will describe the mechanism of local translational control at activated synapses focusing on the role of cytoplasmic polyadenylation of dormant mRNAs.

A New Video Bit Rate Estimation Scheme using a Model for IPTV Services

  • Cho, Hye-Jeong;Noh, Dae-Young;Jang, Seong-Hwan;Kwon, Jae-Cheol;Oh, Seoung-Jun
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.5 no.10
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    • pp.1814-1829
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    • 2011
  • In this paper, we present a model-based video bit rate estimation scheme for reducing the bit rate while maintaining a given target quality in many video streaming services limited by network bandwidth, such as IPTV services. Each item of video content can be stored on a video streaming server and delivered with the estimated bit rate using the proposed scheme, which consists of the following two steps: 1) In the first step, the complexity of each intra-frame in a given item of video content is computed as a frame feature to extract a group of candidate frames with a lot of bits. 2) In the second step, the bit rate of the video content is determined by applying statistical analysis and hypothesis testing to that group. The experimental results show that our scheme can reduce the bit rate by up to 78% with negligible degradation of subjective quality, especially with the low-complexity videos commonly used in IPTV services.

Universal Quantification by Children (보편 양화사 (Universal Quantifier)에 대한 아동들의 해석 양상)

  • 강혜경
    • Language and Information
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    • v.5 no.2
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    • pp.39-55
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    • 2001
  • This paper investigates the idiosyncratic understanding of universal quantifiers such as every, each or all by young children at the ages of 4 to 7, and argues that the phenomenon is explicable in terms of the maturation of both the cognitive system and the linguistic system. Evidence for this dual explanation comes from the fact that the visual input, a picture, plays a key role in determining the children's conceptual representation, suggesting the need for the central integration of visual and linguistic elements; and from the fact that a quantifier in the linguistic input has an intrinsic property, i.e. a <+focus> feature. I have tried to explain the nature of the cognitive factors in terms of the function of the central system, suggesting a modified form of Smith & Tsimpli's (1995) yersion of Fodor's (1983) modularity hypothesis. The categorial status of the quantifier in the children's interpretation is considered, focusing on the movement of that quantifier out of its own extended projection to FP. It is claimed that children initially treat quantifiers as modifiers, rather than functional heads, and that the phenomenon of quantifier spreading by children can be attributed to delay in the development of the relevant functional category, i.e., DP (or QP), in language acquisition.

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3D Quantitative and Qualitative Structure-Activity Relationships of the δ -Opioid Receptor Antagonists

  • Chun, Sun;Lee, Jee-Young;Ro, Seong-Gu;Jeong, Ki-Woong;Kim, Yang-Mee;Yoon, Chang-Ju
    • Bulletin of the Korean Chemical Society
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    • v.29 no.3
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    • pp.656-662
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    • 2008
  • Antagonists of the d -opioid receptor are effective in overcoming resistance against analgesic drugs such as morphine. To identify novel antagonists of the d -opioid receptor that display high potency and low resistance, we performed 3D-QSAR analysis using chemical feature-based pharmacophore models. Chemical features for d -opioid receptor antagonists were generated using quantitative (Catalyst/HypoGen) and qualitative (Catalyst/HipHop) approaches. For HypoGen analysis, we collected 16 peptide and 16 non-peptide antagonists as the training set. The best-fit pharmacophore hypotheses of the two antagonist models comprised identical features, including a hydrophobic aromatic (HAR), a hydrophobic (HY), and a positive ionizable (PI) function. The training set of the HipHop model was constructed with three launched opioid drugs. The best hypothesis from HipHop included four features: an HAR, an HY, a hydrogen bond donor (HBD), and a PI function. Based on these results, we confirm that HY, HAR and PI features are essential for effective antagonism of the d -opioid receptor, and determine the appropriate pharmacophore to design such antagonists.

Adenosine Kinase Inhibitor Design Based on Pharmacophore Modeling

  • Lee, Yun-O;Bharatham, Nagakumar;Bharatham, Kavitha;Lee, Keun-Woo
    • Bulletin of the Korean Chemical Society
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    • v.28 no.4
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    • pp.561-566
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    • 2007
  • Adenosine kinase (AK) is a ubiquitous intracellular enzyme, which catalyzes the phosphorylation of adenosine (ADO) to adenosine monophosphate (AMP). AK inhibitors have therapeutic potential as analgesic and antiinflammatory agents. A chemical feature based pharmacophore model has been generated from known AK inhibitors (26 training set compounds) by HypoGen module implemented in CATALYST software. The top ranked hypothesis (Hypo1) contained four features of two hydrogen-bond acceptors (HBA) and two hydrophobic aromatics (Z). Hypo1 was validated by 124 test set molecules with a correlation coefficient of 0.905 between experimental and estimated activity. It was also validated by CatScramble method. Thus, the Hypo1 was exploited for searching new lead compounds over 238,819 chemical compounds in NCI database and then the selected compounds were screened based on restriction estimated activity and Lipinski's rules to evaluate their drug-like properties. Finally we could obtain 72 new lead candidates and the two best compound structures from them were posted.

A Study on the Effects of a Relationship Marketing on the Customer Response and Long-Term Relationship Orientation in Freight Forwarder (프레이트 포워더의 관계마케팅이 고객반응, 장기적 관계지향성에 미치는 영향에 관한 연구)

  • Choi, Hyung-Rim;Hwang, Seok-Jun;Hong, Soon-Goo;Lee, Kang-Bae;Gang, Seong-Ho
    • Journal of Fisheries and Marine Sciences Education
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    • v.24 no.1
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    • pp.111-122
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    • 2012
  • This study aims to analyze a relationship marketing of freight forwarders, and based on this, customer's satisfaction, trust, and long-term relationship orientation are additionally analyzed. Through previous research, a relationship marketing of freight forwarders is considered, at the same time, the key factors of a relationship marketing is divided into reputation, physical feature, size, and professionalism. Targets of survey are companies which are registered in Korea complex transportation forward association. And a total of 292 questionnaires are collected from freight forwarder in Basan and Kyongnam from November 7 through November 18 in 2011. The result of hypothesis testing, show that relations between freight forwarders and customers is mightily important. In the future research, what effects of maintaining relation between freight forwarders and customers should be analyzed.

On the Vegetation Zone of Mt. Paektu (백두산의 식생대에 관하여)

  • 임양재;심재국
    • The Korean Journal of Ecology
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    • v.21 no.5_2
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    • pp.501-518
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    • 1998
  • Mt. Paektu(2,749.6m)m the biggest mountain in Northeast Asia, located on the border line of Korea and China is characterized as an aspite with broad gentle mountain area and rich biota. however, it seems that the study of forest vegetational feature or vegetation zones in the whole area of this mountain is not yet sufficient in spite of contribution by many investigators. in this paper thermal climatic approach was carried out for the determination of vegetation zones of the mountain with the meteorological data of four stations including Cheonjj and various vegetational data. the application of Warmth Index and/or coldness Index(Kira 1977) for the determination of forest vegetation boundary was useful also here, and their boundaries largely coincided with those of thermal indicies obtained in the Korean Peninsula(Yim and Kira, 1975), including the lapse rate of air temperature along increasing elevation. However, in the mountain the boundary of vegetation zones in not clear like those of mountains in Korea. It may be due so the topographic differences between this area and the Korean Peninsula. Besides, the broad ecotones between different vegetations in this area support the vegetation continum concept rather than the unit concept, and the limit of timber line or tree line reflects various hypothesis(Steven and fox 1991). Therefore, for the explantion of vegetation zone of this area should be considered topography or soil condition, for example, as known the hierachy of ecological units (zonobiomes, orobiomes and pedobiomes, Walter, 1973).

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Circumnuclear gas around the central AGN in a cool-core cluster, A1644-South

  • Baek, Junhyun;Chung, Aeree;Kim, Jae-Woo;Jung, Taehyun
    • The Bulletin of The Korean Astronomical Society
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    • v.45 no.1
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    • pp.30.2-31
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    • 2020
  • We present the properties of circumnuclear gas associated with the AGN located in the center of Abell 1644-South. A1644-S is the main cluster in a merging system, which is also known for gas sloshing in its core as seen in X-ray. The X-ray emission of A1644-S shows a rapidly declining profile, indicating the presence of cooling gas flow. This flow of cool gas may fuel the supermassive black hole embedded in the brightest cluster galaxy, leading to the activation of the central AGN. Indeed, we find a parsec-scale bipolar jet feature in the center of A1644-S in our recent KaVA observation, which implies that its central AGN is likely to have been (re)powered quite recently. In order to verify the hypothesis that cooling gas flow in the cluster core can (re)activate the central AGN, we probe the cold gas properties of the central 1 kpc region of A1644-S using the archival VLA and ALMA data. Based on the spatially resolved morphology and kinematics of HI and CO gas, we challenge to identify inflow/outflow gas streams and clumps. We study the role of circumnuclear cool gas in fueling the centrally located cluster AGN in the cool-core environment. We also discuss how the feedback due to the (re)powered AGN affects the surrounding medium.

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Techniques for Improving Host-based Anomaly Detection Performance using Attack Event Types and Occurrence Frequencies

  • Juyeon Lee;Daeseon Choi;Seung-Hyun Kim
    • Journal of the Korea Society of Computer and Information
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    • v.28 no.11
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    • pp.89-101
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    • 2023
  • In order to prevent damages caused by cyber-attacks on nations, businesses, and other entities, anomaly detection techniques for early detection of attackers have been consistently researched. Real-time reduction and false positive reduction are essential to promptly prevent external or internal intrusion attacks. In this study, we hypothesized that the type and frequency of attack events would influence the improvement of anomaly detection true positive rates and reduction of false positive rates. To validate this hypothesis, we utilized the 2015 login log dataset from the Los Alamos National Laboratory. Applying the preprocessed data to representative anomaly detection algorithms, we confirmed that using characteristics that simultaneously consider the type and frequency of attack events is highly effective in reducing false positives and execution time for anomaly detection.