Showing papers by "Korea University published in 2008"
TL;DR: The Compact Muon Solenoid (CMS) detector at the Large Hadron Collider (LHC) at CERN as mentioned in this paper was designed to study proton-proton (and lead-lead) collisions at a centre-of-mass energy of 14 TeV (5.5 TeV nucleon-nucleon) and at luminosities up to 10(34)cm(-2)s(-1)
Abstract: The Compact Muon Solenoid (CMS) detector is described. The detector operates at the Large Hadron Collider (LHC) at CERN. It was conceived to study proton-proton (and lead-lead) collisions at a centre-of-mass energy of 14 TeV (5.5 TeV nucleon-nucleon) and at luminosities up to 10(34)cm(-2)s(-1) (10(27)cm(-2)s(-1)). At the core of the CMS detector sits a high-magnetic-field and large-bore superconducting solenoid surrounding an all-silicon pixel and strip tracker, a lead-tungstate scintillating-crystals electromagnetic calorimeter, and a brass-scintillator sampling hadron calorimeter. The iron yoke of the flux-return is instrumented with four stations of muon detectors covering most of the 4 pi solid angle. Forward sampling calorimeters extend the pseudo-rapidity coverage to high values (vertical bar eta vertical bar <= 5) assuring very good hermeticity. The overall dimensions of the CMS detector are a length of 21.6 m, a diameter of 14.6 m and a total weight of 12500 t.
5,193 citations
TL;DR: This tutorial review focuses on the recent development of rhodamine derivatives, in which the spirolactam to ring-opened amide (fluorescent) process was utilized.
Abstract: This tutorial review focuses on the recent development of rhodamine derivatives, in which the spirolactam (non-fluorescent) to ring-opened amide (fluorescent) process was utilized.
1,481 citations
TL;DR: Although the optical analogs of 2D NMR do not provide an atomic resolution structure of complex molecules, optical domain multi-dimensional spectroscopy has certain advantages because of the dramatic gain in time resolution possible and the ability to directly observe and quantify the couplings between quantum states involved in molecular dynamical processes.
Abstract: Theoretical descriptions of two-dimensional (2D) vibrational and electronic spectroscopy are presented By using a coupled multi-chromophore model, some examples of 2D spectroscopic studies of peptide solution structure determination and excitation transfer process in electronically coupled multi-chromophore system are discussed A few remarks on perspectives of this research area are given
720 citations
TL;DR: ESD is an effective and safe therapy in the management of early gastric neoplasms and endoscopists have to accept the need for advanced endoscopic techniques for performing ESD in the case of large lesions, scar lesions, undifferentiated cancers, or for the lesions in the upper portion of the stomach.
558 citations
TL;DR: It is found that for human dynamics memory is weak, and the bursty character is due to the changes in the interevent time distribution, and it is shown that current models lack in their ability to reproduce the activity pattern observed in real systems, opening up avenues for future work.
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 intense 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. Here we propose to characterize the bursty nature of real signals using orthogonal measures quantifying two distinct mechanisms leading to burstiness: the interevent time distribution and the 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 the 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 avenues for future work. Copyright c �EPLA, 2008
461 citations
TL;DR: This paper presents power-control strategies of a grid-connected hybrid generation system with versatile power transfer, the combination of photovoltaic array, wind turbine, and battery storage via a common dc bus, and its control system.
Abstract: This paper presents power-control strategies of a grid-connected hybrid generation system with versatile power transfer. The hybrid system is the combination of photovoltaic (PV) array, wind turbine, and battery storage via a common dc bus. Versatile power transfer was defined as multimodes of operation, including normal operation without use of battery, power dispatching, and power averaging, which enables grid- or user-friendly operation. A supervisory control regulates power generation of the individual components so as to enable the hybrid system to operate in the proposed modes of operation. The concept and principle of the hybrid system and its control were described. A simple technique using a low-pass filter was introduced for power averaging. A modified hysteresis-control strategy was applied in the battery converter. Modeling and simulations were based on an electromagnetic-transient-analysis program. A 30-kW hybrid inverter and its control system were developed. The simulation and experimental results were presented to evaluate the dynamic performance of the hybrid system under the proposed modes of operation.
451 citations
Gyeongsang National University1, University of Tokyo2, Budker Institute of Nuclear Physics3, École Polytechnique Fédérale de Lausanne4, Tata Institute of Fundamental Research5, University of Sydney6, Polish Academy of Sciences7, University of Maribor8, National Taiwan University9, National Central University10, Hanyang University11, Sungkyunkwan University12, University of Melbourne13, Virginia Tech14, University of Ljubljana15, Osaka University16, Nagoya University17, Nara Women's University18, Tohoku Gakuin University19, Kyungpook National University20, Saga University21, Tokyo Institute of Technology22, Yonsei University23, Chiba University24, Niigata University25, Seoul National University26, Graduate University for Advanced Studies27, University of Cincinnati28, Panjab University, Chandigarh29, University of Giessen30, Austrian Academy of Sciences31, Osaka City University32, Tokyo University of Agriculture and Technology33, Toho University34, Kanagawa University35, University of Nova Gorica36, Tokyo Metropolitan University37, National United University38, Korea University39, University of Science and Technology of China40
TL;DR: In this paper, the authors presented a method to detect the presence of a tumor in the human brain using the Web of Science Record created on 2010-11-05, modified on 2017-12-10.
Abstract: Reference EPFL-ARTICLE-154575doi:10.1103/PhysRevLett.100.142001View record in Web of Science Record created on 2010-11-05, modified on 2017-12-10
427 citations
426 citations
TL;DR: The results show that distinguishing among different types of owners is instrumental in enhancing the understanding of the nature of the relationship between financial slack and R&D investments.
Abstract: We use agency theory to examine the influence of ownership structure on the relationship between financial slack and R&D investments, highlighting how that relationship might differ depending on the identity of the owners, and their potentially different interests. In doing so, we extend the scope of agency theory by examining the principal-principal conflicts of interests that may exist among different types of owners. Using a sample of Korean manufacturing firms in R&D-intensive industries between 1998 and 2003, we find that financial slack has an inverted U-shaped relationship with R&D investments. Furthermore, that relationship varies depending on the presence of different types of owners. Family ownership positively moderates the relationship between financial slack and R&D investments, whereas domestic institutional investors and foreign investors negatively moderate that relationship. Our results show that distinguishing among different types of owners is instrumental in enhancing our understanding of the nature of the relationship between financial slack and R&D investments.
397 citations
TL;DR: Recent developments in nanobiocatalysis are described and their potential applications in various fields, such as trypsin digestion in proteomic analysis, antifouling, and biofuel cells are described.
391 citations
TL;DR: This poster presents a probabilistic procedure to characterize the response of the immune system to laser-spot assisted, 3D image analysis of central nervous system injury.
Abstract: Reference LPI-ARTICLE-2008-048doi:10.1002/anie.200703852View record in Web of Science Record created on 2008-01-16, modified on 2016-08-08
TL;DR: A nanowire-based gas sensor is fabricated using a simple method of growing SnO(2) nanowires bridging the gap between two pre-patterned Au catalysts, in which the electrical contacts to the Nanowires are self-assembled during the synthesis of the nanOWires.
Abstract: We fabricated a nanowire-based gas sensor using a simple method of growing SnO2 nanowires bridging the gap between two pre-patterned Au catalysts, in which the electrical contacts to the nanowires are self-assembled during the synthesis of the nanowires. The gas sensing capability of this network-structured gas sensor was demonstrated using a diluted NO2. The sensitivity, as a function of temperature, was highest at 200 °C and was determined to be 18 and 180 when the NO2 concentration was 0.5 and 5 ppm, respectively. Our sensor showed higher sensitivity compared to different types of sensors including SnO2 powder-based thin films, SnO2 coating on carbon nanotubes or single/multiple SnO2 nanobelts. The enhanced sensitivity was attributed to the additional modulation of the sensor resistance due to the potential barrier at nanowire/nanowire junctions as well as the surface depletion region of each nanowire.
TL;DR: The facile immobilization of PDA vesicles on solid substrates and the affinity-induced fluorescence emission combine to make this system applicable to the fabrication of label-free PDA sensors.
Abstract: This Account describes a new strategy for the preparation of label-free sensor systems based on the fluorogenic properties of the conjugated polymer, polydiacetylene (PDA). PDA has been extensively investigated as a sensor matrix, owing to a brilliant blue-to-red color transition that takes place in response to environmental perturbations. It has been known for some time that “blue-phase” PDAs are nonfluorescent while their “red-phase” counterparts fluoresce. For the most part, however, the significance of the different fluorogenic properties of PDAs has been ignored in the context of sensor applications. In the course of developing PDA-based sensors, we discovered that PDA vesicles can be readily immobilized on solid substrates. This is an attractive property of PDAs since it leads to the combined advantages of the vesicle sensors (which have three-dimensional interactions between sensor and target molecules) and film sensors (which are applicable to a two-dimensional array or chip format). Stable blue-p...
TL;DR: In this article, a three-dimensional, extrinsically enriched meshfree method for initiation, branching, growth and coalescence of an arbitrary number of cracks in non-linear solids including large deformations, for statics and dynamics is presented.
TL;DR: This article examined the motivations for public equity offers, using a sample of 17,226 initial public offerings and 13,142 seasoned equity offerings from 38 countries between 1990 and 2003, and estimated the uses of funds raised in both initial and seasoned offerings.
TL;DR: A survey of NLO chromophores and materials incorporating them can be found in this article, where the authors provide a brief introduction explaining overall principles relating to the origin of second-order nonlinear optical properties.
TL;DR: Performance of the proposed scheme is shown to be better than the original difference expansion scheme by Tian and its improved version by Kamstra and Heijmans and can be possible by exploiting the quasi-Laplace distribution of the difference values.
Abstract: Reversible data embedding theory has marked a new epoch for data hiding and information security. Being reversible, the original data and the embedded data should be completely restored. Difference expansion transform is a remarkable breakthrough in reversible data-hiding schemes. The difference expansion method achieves high embedding capacity and keeps distortion low. This paper shows that the difference expansion method with the simplified location map and new expandability can achieve more embedding capacity while keeping the distortion at the same level as the original expansion method. Performance of the proposed scheme in this paper is shown to be better than the original difference expansion scheme by Tian and its improved version by Kamstra and Heijmans. This improvement can be possible by exploiting the quasi-Laplace distribution of the difference values.
TL;DR: Qualitative and quantitative analyses of the representative host-based and network-based mobility management approaches, which highlight the main desirable features and key strengths of PMIPv6 are presented.
Abstract: Recently, a network-based mobility management protocol called Proxy Mobile IPv6 (PMIPv6) is being actively standardized by the IETF NETLMM working group, and is starting to attract considerable attention among the telecommunication and Internet communities. Unlike the various existing protocols for IP mobility management such as Mobile IPv6 (MIPv6), which are host-based approaches, a network-based approach such as PMIPv6 has salient features and is expected to expedite the real deployment of IP mobility management. In this article, starting by showing the validity of a network-based approach, we present qualitative and quantitative analyses of the representative host-based and network-based mobility management approaches (i.e., MIPv6 and PMIPv6), which highlight the main desirable features and key strengths of PMIPv6. Furthermore, a comprehensive comparison among the various existing well-known mobility support protocols is investigated. Although the development of PMIPv6 is at an early stage yet, it is strongly expected that PMIPv6 will be a promising candidate solution for realizing the next-generation all-IP mobile networks.
TL;DR: Compared the clinical characteristics of two GBM patient groups divided according to CD133-positive cell ratios, the results suggest thatCD133-negative cells of GBMs also possess tumor-initiating potential, which is indicative of complexity in the identification of cancer cells for therapeutic targeting.
TL;DR: The Korean version of the PHQ-9 is an appropriate diagnostic tool for depression, and a score of 5 is the optimal cutoff for Korean elderly subjects, suggesting an optimal cutoff score to screen for major depressive disorders.
TL;DR: In this paper, the gas sensing characteristics of the p-type oxide semiconductor were investigated and the sensor showed two opposite NO2 sensing behaviors; the resistance decreased upon exposure to 30 −100 -ppm NO2, but increased upon contact with ≤ 5 −5 −ppm No2.
Abstract: CuO nanowires (NWs) were grown by the thermal oxidation of Cu foil at 400 °C and gas sensors were fabricated by the deposition of a solution containing the CuO NWs. At 300–370 °C, the sensor resistance increased upon exposure to 30–100 ppm CO. This has been explained by the gas sensing characteristics of the p-type oxide semiconductor. In contrast, the sensor showed two opposite NO2 sensing behaviors; the resistance decreased upon exposure to 30–100 ppm NO2, but increased upon contact with ≤5 ppm NO2. The increase in resistance upon contact with both reducing CO and a low concentration of oxidizing NO2 gases provides a simple and novel sensing algorithm for air quality control in automotive cabins.
TL;DR: In this article, the authors empirically examined how online communities influence brand commitment and subsequent customer behavior in a field study of over 1,500 members of an existing online community for herbal products.
Abstract: Companies are increasingly using online communities to create value for the firm and their customers. To date, evidence regarding the effectiveness of online communities as a marketing tool has been primarily anecdotal. Yet, industry practice suggests that online communities add value in several ways by: 1) building brand awareness and image, 2) providing access to the voice of loyal customers, 3) increasing supplier commitment, and 4) generating revenue from new and existing customers. Relying on social identity theory and reciprocal action theory, we develop a framework that explores the process of how a firm's online community enhances consumers' brand commitment. We empirically examine how online communities influence brand commitment and subsequent customer behaviour in a field study of over 1,500 members of an existing online community for herbal products. In our analysis, we confirm that online community commitment is a key influence on brand commitment. We also find that online community participa...
TL;DR: For Au + Au collisions at 200 GeV, neutral pion production is measured with good statistics for transverse momentum, pT, and a fivefold suppression is found, which is essentially constant for 5 < pT < 20 GeV/c.
Abstract: For Au + Au collisions at 200 GeV, we measure neutral pion production with good statistics for transverse momentum, p(T), up to 20 GeV/c. A fivefold suppression is found, which is essentially constant for 5 in the parton quenching model. The spectral shape is similar for all collision classes, and the suppression does not saturate in Au + Au collisions.
TL;DR: In this article, a polymeric dry electrode that changes its shape in a way that supports the electrode's contact with the skin and does not cause skin irritations or allergic reactions is presented.
Abstract: In this paper, we present a novel polymeric dry electrode that (1) changes its shape in a way that supports the electrode's contact with the skin and (2) that does not cause skin irritations or allergic reactions For a polymeric substrate of electrodes, we have used the elastomer poly(dimethylsiloxane), which is known to be inexpensive, biocompatible, and amenable to micro-molding, and to have excellent gas and water permeability We have established a process by which one can deposit a metal layer on the PDMS substrate, etch the electrode patterns chemically and with good resolution, and package the electrode so that it is easily wearable on the forearm We measured the impedance according to the frequency change and compared the results with those of Ag/AgCl electrodes Afterward, we measured the ECG signal and investigated possible artifacts caused by motion For the feasibility of long-term monitoring, we examined the influence of surface electrodes on the skin after 7 days of ECG monitoring In conclusion, our PDMS-based dry electrode measured the ECG signals with comparatively good fidelity, but showed better skin compatibility after long-term tests We expect that our method for the production of PDMS-based dry electrodes will be broadly applicable to the field of ubiquitous biosignal monitoring
TL;DR: It was found that readiness for change had an indirect effect on behavioral intention to use an ERP system and was found to be enhanced by two factors: organizational commitment and perceived personal competence.
TL;DR: In this paper, the relative size of spillover and competition effects in China between foreign entrants and local firms, among foreign entrants, and among local firms was examined, and it was shown that the increased presence of foreign entrants has generally benefited local firms nationally, but has negatively affected the survival rates of local firms in regional markets.
Abstract: Combining the FDI spillover literature with a competitor analysis framework, we examine the relative size of spillover and competition effects in China between foreign entrants and local firms, among foreign entrants, and among local firms. Our results show that the increased presence of foreign entrants has generally benefited local firms nationally, but has negatively affected the survival rates of local firms in regional markets. Surprisingly, foreign entrants are crowded out not only by their peers, but also by reformed local firms at both the national and regional levels. Copyright © 2008 John Wiley & Sons, Ltd.
TL;DR: The synthesis and evaluation of a novel calix[4]arene-based fluorescent chemosensor 8 for the detection of Cd(2+) and Zn(2+) and the fluorescent spectra changes observed upon addition of various metal ions show that 8 is highly selective for Cd (2+)
Abstract: The synthesis and evaluation of a novel calix[4]arene-based fluorescent chemosensor 8 for the detection of Cd(2+) and Zn(2+) is described. The fluorescent spectra changes observed upon addition of various metal ions show that 8 is highly selective for Cd(2+) and Zn(2+) over other metal ions. Addition of Cd(2+) and Zn(2+) to the solution of 8 results in ratiometric measurement.
TL;DR: The pharmacological actions of these flavonoids suggest their potential activity for treatment of allergic inflammatory diseases through the down-regulation of mast cell activation.
Abstract: Mast cells participate in allergy and inflammation by secreting inflammatory mediators such as histamine and proinflammatory cytokines. Flavonoids are naturally occurring molecules with antioxidant, cytoprotective, and antiinflammatory actions. However, effect of flavonoids on the release of histamine and proinflammatory mediator, and their comparative mechanism of action in mast cells were not well defined. Here, we compared the effect of six flavonoids (astragalin, fisetin, kaempferol, myricetin, quercetin, and rutin) on the mast cell-mediated allergic inflammation. Fisetin, kaempferol, myricetin, quercetin, and rutin inhibited IgE or phorbol-12-myristate 13-acetate and calcium ionophore A23187 (PMACI)-mediated histamine release in RBL-2H3 cells. These five flavonoids also inhibited elevation of intracellular calcium. Gene expressions and secretion of proinflammatory cytokines such as tumor necrosis factor-α (TNF-α), interleukin (IL)-1β, IL-6, and IL-8 were assessed in PMACI-stimulated human mast cells (HMC-1). Fisetin, quercetin, and rutin decreased gene expression and production of all the proinflammatory cytokines after PMACI stimulation. Myricetin attenuated TNF-α and IL-6 but not IL-1β and IL-8. Fisetin, myricetin, and rutin suppressed activation of NF-κB indicated by inhibition of nuclear translocation of NF-κB, NF-κB/DNA binding, and NF-κB-dependent gene reporter assay. The pharmacological actions of these flavonoids suggest their potential activity for treatment of allergic inflammatory diseases through the down-regulation of mast cell activation.
TL;DR: In this article, a three-dimensional mesh-free method for modeling arbitrary crack initiation and crack growth in reinforced concrete structure is presented, based on a partition of unity concept and formulated for geometrically non-linear problems.
TL;DR: It is found that attitude, social influence, media influence, perceived mobility, and perceived monetary value influence consumers’ intention to continue usage of mobile data services.
Abstract: Due to rapid advances in the Internet and wireless technologies, a ubiquitous computing world is becoming a reality in the form of mobile computing. At the center of this phenomenon is mobile data services which arise from the convergence of advanced mobile communication technologies with data services. Despite the rapid growth in mobile data services, research into consumers' usage behavior is scarce. This study attempts to identify and empirically assess the factors that drive consumers' acceptance of mobile data services. A research model based on the decomposed theory of planned behavior and incorporating factors that represent personal needs and motivations in using mobile data services is presented. The model is tested via an online survey of 811 consumers of four categories of mobile data services (i.e., communications, information content, entertainment, and commercial transactions) associated with different usage contexts. We found that attitude, social influence, media influence, perceived mobility, and perceived monetary value influence consumers' intention to continue usage of mobile data services. In addition, perceived ease of use, perceived usefulness, and perceived enjoyment influence attitude toward continued usage of mobile data services. Finally, separate analysis of the different categories of mobile data services highlights the influence of individual usage context on consumers' behavior.