Showing papers by "Korea University published in 2006"
TL;DR: Choi et al. as mentioned in this paper reported strong OLS and instrumental variable evidence that an overall corporate governance index is an important and likely causal factor in explaining the market value of Korean public companies.
Abstract: We report strong OLS and instrumental variable evidence that an overall corporate governance index is an important and likely causal factor in explaining the market value of Korean public companies. We construct a corporate governance index (KCGI, 0~100) for 515 Korean companies based on a 2001 Korea Stock Exchange survey. In OLS, a worst-to-best change in KCGI predicts a 0.47 increase in Tobin's q (about a 160% increase in share price). This effect is statistically strong (t = 6.12) and robust to choice of market value variable (Tobin's q, market/book, and market/sales), specification of the governance index, and inclusion of extensive control variables. We rely on unique features of Korean legal rules to construct an instrument for KCGI. Good instruments are not available in other comparable studies. Two-stage and three-stage least squares coefficients are larger than OLS coefficients and are highly significant. Thus, this paper offers evidence consistent with a causal relationship between an overall governance index and higher share prices in emerging markets. We also find that Korean firms with 50% outside directors have 0.13 higher Tobin's q (roughly 40% higher share price), after controlling for the rest of KCGI. This effect, too, is likely causal. Thus, we report the first evidence consistent with greater board independence causally predicting higher share prices in emerging markets.
1,063 citations
01 Sep 2006-International Journal of Human-computer Studies \/ International Journal of Man-machine Studies
TL;DR: In this article, the authors report on a study that attempts to expand the set of post-adoption beliefs in the expectation-confirmation model (ECM) in order to extend the application of the ECM beyond an instrumental focus.
Abstract: The expectation-confirmation model (ECM) of IT continuance is a model for investigating continued information technology (IT) usage behavior. This paper reports on a study that attempts to expand the set of post-adoption beliefs in the ECM, in order to extend the application of the ECM beyond an instrumental focus. The expanded ECM, incorporating the post-adoption beliefs of perceived usefulness, perceived enjoyment and perceived ease of use, was empirically validated with data collected from an on-line survey of 811 existing users of mobile Internet services. The data analysis showed that the expanded ECM has good explanatory power (R^2=57.6% of continued IT usage intention and R^2=67.8% of satisfaction), with all paths supported. Hence, the expanded ECM can provide supplementary information that is relevant for understanding continued IT usage. The significant effects of post-adoption perceived ease of use and perceived enjoyment signify that the nature of the IT can be an important boundary condition in understanding the continued IT usage behavior. At a practical level, the expanded ECM presents IT product/service providers with deeper insights into how to address IT users' satisfaction and continued patronage.
931 citations
TL;DR: The results show that the cyanoacrylic acid groups are essentially coplanar with respect to the thiophene units, reflecting the strong conjugation across theThiophene-cyanoac acrylic groups.
Abstract: Novel organic sensitizers comprising donor, electron-conducting, and anchoring groups were engineered at molecular level and synthesized. The functionalized unsymmetrical organic sensitizers 3-{5-[N,N-bis(9,9-dimethylfluorene-2-yl)phenyl]-thiophene-2-yl}-2-cyano-acrylic acid (JK-1) and 3-{5'-[N,N-bis(9,9-dimethylfluorene-2-yl)phenyl]-2,2'-bisthiophene-5-yl}-2-cyano-acrylic acid (JK-2), upon anchoring onto TiO2 film, exhibit unprecedented incident photon to current conversion efficiency of 91%. The photovoltaic data using an electrolyte having composition of 0.6 M M-methyl-N-butyl imidiazolium iodide, 0.04 M iodine, 0.025 M LiI, 0.05 M guanidinium thiocyanate, and 0.28 M tert-butylpyridine in a 15/85 (v/v) mixture of valeronitrile and acetonitrile revealed a short circuit photocurrent density of 14.0 +/- 0.2 mA/cm2, an open circuit voltage of 753 +/- 10 mV, and a fill factor of 0.76 +/- 0.02, corresponding to an overall conversion efficiency of 8.01% under standard AM 1.5 sunlight. DFT/TDDFT calculations have been performed on the two organic sensitizers to gain insight into their structural, electronic, and optical properties. Our results show that the cyanoacrylic acid groups are essentially coplanar with respect to the thiophene units, reflecting the strong conjugation across the thiophene-cyanoacrylic groups. Molecular orbitals analysis confirmed the experimental assignment of redox potentials, while TDDFT calculations allowed assignment of the visible absorption bands.
765 citations
TL;DR: In this paper, various inorganic fillers including aluminum nitride (AlN), wollastonite, silicon carbide whisker (SiC), and boron nitride(BN) with different shape and size were used alone or in combination to prepare thermally conductive polymer composites.
Abstract: This study aims at investigating package materials based on polymer matrix for microelectronics. The next generation package materials are expected to possess high heat dissipation capability in addition to low coefficient of thermal expansion (CTE) as the accumulated heat from high performance electronic devices should be removed for proper operation. In this study, various inorganic fillers including aluminum nitride (AlN), wollastonite, silicon carbide whisker (SiC) and boron nitride (BN) with different shape and size were used alone or in combination to prepare thermally conductive polymer composites. In case of AlN, titanate coupling agent was used for the surface treatment of fillers. The use of hybrid filler was found to be effective in increasing thermal conductivity of the composite probably due to the enhanced connectivity offered by structuring filler with high aspect ratio in hybrid filler. For given filler loading, the use of larger particle and surface treated filler resulted in composite materials with enhanced thermal conductivity. The surface treatment of filler also allowed producing the composites with lower CTE.
733 citations
01 Dec 2006
Abstract: This study examines the utility of three prospective models for understanding the continued IT usage behavior. The three models include: Expectation-Confirmation Model in IT Domain (ECM-IT), Technology Acceptance Model (TAM), and a hybrid model integrating TAM and ECM-IT (extended ECM-IT). Based on a survey of 1826 mobile Internet users, the LISREL analysis shows that all three models meet the various goodness-of-fit criteria. When compared using special indices for differentiating among alternative good models, TAM has the best fit to the data followed by ECM-IT, and the extended ECM-IT. In terms of variance explained for intention to continue IT usage, the extended ECM-IT has the highest R2 (67%) followed by TAM (63%), and ECM-IT (50%). We conclude that TAM is the most parsimonious and generic model that can be used to study both initial and continued IT adoption; the extended ECM-IT explains continued IT usage behavior as well as TAM; and both the ECM-IT and extended ECM-IT models provide additional information to increase our understanding of continued IT usage.
717 citations
TL;DR: In this article, measurements of {nu}{sub {mu}} disappearance in K2K, the KEK to Kamioka long-baseline neutrino oscillation experiment are presented.
Abstract: We present measurements of {nu}{sub {mu}} disappearance in K2K, the KEK to Kamioka long-baseline neutrino oscillation experiment. One-hundred and twelve beam-originated neutrino events are observed in the fiducial volume of Super-Kamiokande with an expectation of 158.1{sub -8.6}{sup +9.2} events without oscillation. A distortion of the energy spectrum is also seen in 58 single-ring muonlike events with reconstructed energies. The probability that the observations are explained by the expectation for no neutrino oscillation is 0.0015% (4.3{sigma}). In a two-flavor oscillation scenario, the allowed {delta}m{sup 2} region at sin{sup 2}2{theta}=1 is between 1.9 and 3.5x10{sup -3} eV{sup 2} at the 90% C.L. with a best-fit value of 2.8x10{sup -3} eV{sup 2}.
672 citations
TL;DR: In this article, a phase inversion process was used for the preparation of multi-walled carbon nanotubes (MWNTs)/polysulfone (PSf) blend membranes using N -methyl-2-pyrrolidinone (NMP) as a solvent and water as a coagulant.
523 citations
TL;DR: The authors show that perceptual or conceptual similarity is not necessary to obtain mapping effects; a type of structural similarity is sufficient and polarity correspondence is sufficient to produce mapping effects.
Abstract: Differences in performance with various stimulus-response mappings are among the most prevalent findings for binary choice reaction tasks. The authors show that perceptual or conceptual similarity is not necessary to obtain mapping effects; a type of structural similarity is sufficient. Specifically, stimulus and response alternatives are coded as positive and negative polarity along several dimensions, and polarity correspondence is sufficient to produce mapping effects. The authors make the case for this polarity correspondence principle using the literature on word-picture verification and then provide evidence that polarity correspondence is a determinant of mapping effects in orthogonal stimulus-response compatibility, numerical judgment, and implicit association tasks. The authors conclude by discussing implications of this principle for interpretation of results from binary choice tasks and future model development.
469 citations
TL;DR: In this article, the effect of antimicrobial activities of chitosan and acetic acid against Escherichia coli was investigated by the method of Acetic acid hydrolysis, and the mechanism of antibacterial activity was that E. coli was flocculated.
446 citations
TL;DR: The results identify a molecular surface likely to be recognized by FT‐ and/or TFL1‐specific interactors, and identify a region important in vivo localizes to a 14‐amino‐acid segment that evolves very rapidly in T FL1 orthologs, but is almost invariant in FT orthology.
Abstract: The Arabidopsis genes FT and TERMINAL FLOWER1 (TFL1) encode related proteins with similarity to human Raf kinase inhibitor protein. FT, and likely also TFL1, is recruited to the promoters of floral genes through interaction with FD, a bZIP transcription factor. FT, however, induces flowering, while TFL1 represses flowering. Residues responsible for the opposite activities of FT and TFL1 were mapped by examining plants that overexpress chimeric proteins. A region important in vivo localizes to a 14-amino-acid segment that evolves very rapidly in TFL1 orthologs, but is almost invariant in FT orthologs. Crystal structures show that this segment forms an external loop of variable conformation. The only residue unambiguously distinguishing the FT and TFL1 loops makes a hydrogen bond with a residue near the entrance of a potential ligand-binding pocket in TFL1, but not in FT. This pocket is contacted by a C-terminal peptide, which also contributes to the opposite FT and TFL1 activities. In combination, these results identify a molecular surface likely to be recognized by FT- and/or TFL1-specific interactors.
431 citations
TL;DR: This paper proposed two empirical heuristics: per-document text normalization and feature weighting method, which performed very well in the standard benchmark collections, competing with state-of-the-art text classifiers based on a highly complex learning method such as SVM.
Abstract: While naive Bayes is quite effective in various data mining tasks, it shows a disappointing result in the automatic text classification problem Based on the observation of naive Bayes for the natural language text, we found a serious problem in the parameter estimation process, which causes poor results in text classification domain In this paper, we propose two empirical heuristics: per-document text normalization and feature weighting method While these are somewhat ad hoc methods, our proposed naive Bayes text classifier performs very well in the standard benchmark collections, competing with state-of-the-art text classifiers based on a highly complex learning method such as SVM
TL;DR: In this article, a membrane capacitive deionization (MCDI) system was developed to test desalination performance for power plant wastewater, and the maximum salt removal rate and electric energy consumption were about 92% and 1.96 Wh/L, respectively.
15 Sep 2006-Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment
TL;DR: The D0 experiment enjoyed a very successful data-collection run at the Fermilab Tevatron collider between 1992 and 1996 as discussed by the authors, and the detector has been upgraded to take advantage of improvements to the Tevoton and to enhance its physics capabilities.
Abstract: The D0 experiment enjoyed a very successful data-collection run at the Fermilab Tevatron collider between 1992 and 1996. Since then, the detector has been upgraded to take advantage of improvements to the Tevatron and to enhance its physics capabilities. We describe the new elements of the detector, including the silicon microstrip tracker, central fiber tracker, solenoidal magnet, preshower detectors, forward muon detector, and forward proton detector. The uranium/liquid-argon calorimeters and central muon detector, remaining from Run I, are discussed briefly. We also present the associated electronics, triggering, and data acquisition systems, along with the design and implementation of software specific to D0.
TL;DR: In this article, the effect of partial gelatinization and retrogradation on in vitro enzymatic digestibility of waxy rice starch was investigated, and the relationship between the residual crystallinity and digestibility measured.
TL;DR: In this paper, the thermal conductivities of nanofluid containing a small amount of ultra-dispersed diamond (UDD), silver, and silica nanoparticles were measured using a transient hot-wire method.
Abstract: The thermal conductivities of nanofluid containing a small amount of ultra-dispersed diamond (UDD), silver, and silica nanoparticles were measured using a transient hot-wire method. To explain the enhancement of thermal conductivity of nanofluid, the effective volume of nanoparticles was used instead of the real volume to predict the thermal conductivity of nanofluid. The liquid layering on the surface of nanoparticles may be described as the effective volume of nanoparticles. This liquid layering is one important mechanism of the heat transfer in nanofluids. The effective volume of nanoparticles was estimated from high shear viscosity of nanofluid using the Einstein equation. The Hamilton–Crosser model with an effective volume fraction of nanoparticles resulted in better correlation for the thermal conductivities of nanofluids.
TL;DR: In this article, an electron impact trans-cis conformational change of the isolated azobenzene molecules is explained by an electron-impact transcis conformation change of both isomers.
Abstract: We propose to utilize azobenzene as a nanomolecular switch which can be triggered by transmitting electrons above threshold biases. The effect is explained by an electron impact trans-cis conformational change of the isolated azobenzene molecules. The molecular electronic states of both isomers have been measured with spatially resolved scanning tunneling microscopy or spectroscopy, leading to suggested transition pathways of the electron-induced isomerization.
TL;DR: In this paper, the authors confirm a link between mitochondrial dysfunction and type 2 diabetes, and propose a method to confirm the link between mitochondria dysfunction and Type 2 diabetes using a blood test.
Abstract: Aims/hypothesis
The aim of this study was to confirm a link between mitochondrial dysfunction and type 2 diabetes.
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TL;DR: This paper found that the burstiness of natural phenomena is rooted in both the interevent time distribution and memory, for human dynamics memory is weak, and the bursty character is due to changes in the Interevent Time Distribution.
Abstract: The dynamics of a wide range of real systems, from email patterns to earthquakes, display a bursty, intermittent nature, characterized by short timeframes of intensive activity followed by long times of no or reduced activity. The understanding of the origin of such bursty patterns is hindered by the lack of tools to compare different systems using a common framework. We introduce two measures to distinguish the mechanisms responsible for the bursty nature of real signals, changes in the interevent times and memory. We find that while the burstiness of natural phenomena is rooted in both the interevent time distribution and memory, for human dynamics memory is weak, and the bursty character is due to changes in the interevent time distribution. Finally, we show that current models lack in their ability to reproduce the activity pattern observed in real systems, opening up new avenues for future work.
TL;DR: Whether business groups' roles in facilitating affiliate firms' innovation varies by country and time period is explored to compare the innovativeness of firms affiliated with business groups to that of independent firms in two emerging economies: South Korea and Taiwan.
Abstract: Using a comparative institutional perspective, we explore whether business groups' roles in facilitating affiliate firms' innovation varies by country and time period. We compare the innovativeness of firms affiliated with business groups to that of independent firms in two emerging economies: South Korea and Taiwan. On average, business group affiliates outperform independent firms in South Korea, but not in Taiwan, and in the early 1990s, but not in the late 1990s. The existence of alternative institutional infrastructures for innovation might explain these differences. Groups' abilities to share technological knowledge and financial resources among affiliates enables them to create value by promoting innovation in emerging economies, but groups' diversification might inhibit individual affiliates' innovativeness.
TL;DR: This paper develops efficient adaptive sequential and batch-sequential methods for an early detection of attacks that lead to changes in network traffic, such as denial-of-service attacks, worm-based attacks, port-scanning, and man-in-the-middle attacks.
Abstract: Large-scale computer network attacks in their final stages can readily be identified by observing very abrupt changes in the network traffic. In the early stage of an attack, however, these changes are hard to detect and difficult to distinguish from usual traffic fluctuations. Rapid response, a minimal false-alarm rate, and the capability to detect a wide spectrum of attacks are the crucial features of intrusion detection systems. In this paper, we develop efficient adaptive sequential and batch-sequential methods for an early detection of attacks that lead to changes in network traffic, such as denial-of-service attacks, worm-based attacks, port-scanning, and man-in-the-middle attacks. These methods employ a statistical analysis of data from multiple layers of the network protocol to detect very subtle traffic changes. The algorithms are based on change-point detection theory and utilize a thresholding of test statistics to achieve a fixed rate of false alarms while allowing us to detect changes in statistical models as soon as possible. There are three attractive features of the proposed approach. First, the developed algorithms are self-learning, which enables them to adapt to various network loads and usage patterns. Secondly, they allow for the detection of attacks with a small average delay for a given false-alarm rate. Thirdly, they are computationally simple and thus can be implemented online. Theoretical frameworks for detection procedures are presented. We also give the results of the experimental study with the use of a network simulator testbed as well as real-life testing for TCP SYN flooding attacks
TL;DR: The results suggest that macrophages are an important mediator in the initiation period of ischaemia/reperfusion injury and strategies that limit initial macrophage infiltration or activation can be useful in the treatment of acute renal failure.
Abstract: Background. Although neutrophils and T cells are important in mediating renal injury following ischaemia/reperfusion, the role of macrophages is still unknown. Using liposomal clodronate (LC), we investigated the effect of systemic monocyte– macrophage depletion on renal damage in ischaemic acute renal failure in rats. Methods. Male Sprague–Dawley rats were injected by LC or liposomal vehicle and underwent bilateral renal pedicle clamping (40 min) or sham ischaemia. Biochemical and histological renal damage was assessed and gene expression kinetics of tumour necrosis factor-a (TNF-a), interleukin-1b (IL-1b), IL-6 and monocyte chemoattractant protein-1 (MCP-1) using quantitative real-time reverse transcription– polymerase chain reaction were conducted at 4, 24 and 72 h after reperfusion. Results. The percentage of peripheral blood monocytes and ectodysplasin-1-positive cells in liver decreased significantly in LC-treated animals at 24 h. Systemic monocyte–macrophage depletion resulted in (a) less severe tubular necrosis, (b) reduced inflammation and (c) reduced apoptosis of renal tubular epithelial cells. Gene expression kinetics showed that IL-6 gene expression peaked early at 4 h after reperfusion, followed by TNF-a, IL-1b and MCP-1 expressions, which peaked at 24 h. Systemic monocyte– macrophage depletion significantly reduced these cytokine and chemokine gene expressions. Conclusions. These results suggest that macrophages are an important mediator in the initiation period of ischaemia/reperfusion injury and strategies that limit initial macrophage infiltration or activation can be useful in the treatment of acute renal failure.
TL;DR: CT is superior to conventional angiography in delineating the ostial origin and proximal path of an anomalous coronary artery and an understanding of the clinical significance of these anomalies are essential in making a correct diagnosis and planning patient treatment.
Abstract: Congenital abnormalities of the coronary arteries are an uncommon but important cause of chest pain and, in some cases of hemodynamically significant abnormalities, sudden cardiac death. For several decades, premorbid diagnosis of coronary artery anomalies has been made with conventional angiography. However, this imaging technique has limitations due to its projectional and invasive nature. The recent development of electrocardiographically (ECG)-gated multi-detector row computed tomography (CT) allows accurate and noninvasive depiction of coronary artery anomalies of origin, course, and termination. Multi-detector row CT is superior to conventional angiography in delineating the ostial origin and proximal path of an anomalous coronary artery. Familiarity with the CT appearances of various coronary artery anomalies and an understanding of the clinical significance of these anomalies are essential in making a correct diagnosis and planning patient treatment.
TL;DR: The key to the successful generation of highly regular, porous thin films is the use of PMMA as a photodegradable mid-block which leads to nanoporous structures with an unprecedented degree of lateral order.
Abstract: The self-assembly of triblock copolymers of poly(ethylene oxide-b-methyl methacrylate-b-styrene) (PEO-b-PMMA-b-PS), where PS is the major component and PMMA and PEO are minor components, provides a robust route to highly ordered, nanoporous arrays with cylindrical pores of 10-15 nm that show promise in block copolymer lithography These ABC triblock copolymers were synthesized by controlled living radical polymerization, and after solvent annealing, thin films showing defect-free cylindrical microdomains were obtained The key to the successful generation of highly regular, porous thin films is the use of PMMA as a photodegradable mid-block which leads to nanoporous structures with an unprecedented degree of lateral order The power of using a triblock copolymer when compared to a traditional diblock copolymer is evidenced by the ability to exploit and combine the advantages of two separate diblock copolymer systems, the high degree of lateral ordering inherent in PS-b-PEO diblocks plus the facile degradability of PS-b-PMMA diblock copolymer systems, while negating the corresponding disadvantages, poor degradability in PS-b-PEO systems and no long-range order for PS-b-PMMA diblocks
TL;DR: In this article, conductive carbon from three different carbon sources (graphite, carbon black, acetylene black) was used to investigate the electrochemical properties of LiFePO4 and found that the carbon-coated particles were smaller than the bare particles.
TL;DR: Overexpression of NGL-2 in cultured rat neurons increased the number of PSD-95–positive dendritic protrusions and NGL knockdown reduced excitatory, but not inhibitory, synapse numbers and currents, suggesting that NGL regulates the formation of exciteatory synapses.
Abstract: Synaptic cell adhesion molecules (CAMs) regulate synapse formation through their trans-synaptic and heterophilic adhesion. Here we show that postsynaptic netrin-G ligand (NGL) CAMs associate with netrin-G CAMs in an isoform-specific manner and, through their cytosolic tail, with the abundant postsynaptic scaffold postsynaptic density–95 (PSD-95). Overexpression of NGL-2 in cultured rat neurons increased the number of PSD-95–positive dendritic protrusions. NGL-2 located on heterologous cells or beads induced functional presynaptic differentiation in contacting neurites. Direct aggregation of NGL-2 on the surface membrane of dendrites induced the clustering of excitatory postsynaptic proteins. Competitive inhibition by soluble NGL-2 reduced the number of excitatory synapses. NGL-2 knockdown reduced excitatory, but not inhibitory, synapse numbers and currents. These results suggest that NGL regulates the formation of excitatory synapses.
TL;DR: Fearful and Angry-dismissive styles were shown to partially mediate the relationship between childhood adversity and depression or anxiety, and insecure attachment styles predicted both major depression and case anxiety in follow-up.
Abstract: There has been little prospective investigation of the relationship between adult attachment style and clinical levels of anxiety and major depression. This paper seeks to address this, as well as examining the potentially mediating role of adult insecure attachment styles in the relationship between childhood adverse experience and adult disorder. 154 high-risk community women studied in 1990–1995, were followed-up in 1995–1999 to test the role of insecure attachment style in predicting new episodes of anxiety and/or major depressive disorder. The Childhood Experience of Care and Abuse (CECA) and the Attachment Style Interview (ASI) were administered at first interview and the Structured Clinical Interview for DSM-IV (SCID) administered at first and follow-up interview. Major depression and clinical level anxiety disorders (GAD, Social Phobia or Panic and/or Agoraphobia) were assessed at first contact and for the intervening follow-up period. 55% (85/154) of the women had at least one case level disorder in the follow-up period. Only markedly or moderately (but not mildly) insecure attachment styles predicted both major depression and case anxiety in follow-up. Some specificity was determined with Fearful style significantly associated both with depression and Social Phobia, and Angry-Dismissive style only with GAD. Attachment style was unrelated to Panic Disorder and/or Agoraphobia. In addition, Fearful and Angry-dismissive styles were shown to partially mediate the relationship between childhood adversity and depression or anxiety. In order to correctly interpret lifespan models of adult psychiatric disorder, it is necessary to test for mediating factors. Attachment theory provides a framework for explaining how dysfunctional interpersonal style arising from early childhood perpetuates vulnerability to affective disorders. This has implications for intervention and treatment to break cycles of risk.
TL;DR: The role of deformation-induced nanocrystallites on the plasticity of monolithic amorphous alloys was examined using high-resolution transmission electron microscopy in this article.
TL;DR: A novel tag anti-collision scheme called adaptive binary splitting (ABS) is presented, which assigns distinct timeslots to tags by using information obtained from the last identification process.
Abstract: Tag collision arbitration for passive RFID tags is a significant issue for fast tag identification. This letter presents a novel tag anti-collision scheme called adaptive binary splitting (ABS). For reducing collisions, ABS assigns distinct timeslots to tags by using information obtained from the last identification process. Our performance evaluation shows that ABS outperforms other tree based tag anti-collision protocols.
05 Jun 2006
TL;DR: This paper analyzes the existing LANDMARC system, solves the potential problems within it and proposes a more efficient mechanism to enhance the accuracy of indoor localization.
Abstract: The location-aware technology and its application are prerequisite to realize the ubiquitous computing. However, another special system for indoor localization is needed in the complicated indoor environment, where the Global Positioning System (GPS) is not available. RFID technology makes the building up of indoor localization system with low cost possible. LANDMARC is an indoor localization system using RFID technology, which introduces the concept of reference tag to reduce the number of deployed RFID readers and provides high possibility to be used in reality, and we can guarantee the accuracy of localization and thus lower the cost of importing system with it. In this paper, we analyze the existing LANDMARC system, solve the potential problems within it and propose a more efficient mechanism to enhance the accuracy of indoor localization.
TL;DR: The PHENIX experiment as mentioned in this paper measured midrapidity of electrons as a function of centrality in Au+Au collisions at [FORMULA: SEE TEXT] and removed contributions from photon conversions and from light hadron decays, mainly Dalitz decays of pi0 and eta mesons.
Abstract: The PHENIX experiment has measured midrapidity ([FORMULA: SEE TEXT]) transverse momentum spectra ([FORMULA: SEE TEXT]) of electrons as a function of centrality in Au+Au collisions at [FORMULA: SEE TEXT]. Contributions from photon conversions and from light hadron decays, mainly Dalitz decays of pi0 and eta mesons, were removed. The resulting nonphotonic electron spectra are primarily due to the semileptonic decays of hadrons carrying heavy quarks. Nuclear modification factors were determined by comparison to nonphotonic electrons in p+p collisions. A significant suppression of electrons at high pT is observed in central Au+Au collisions, indicating substantial energy loss of heavy quarks.