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Drawing on literatures from a contingency perspective of strategic human resource management and a dynamic resource‐based view, this study examines dynamic patterns of investment in high‐performance work systems (HPWS) to support labor productivity of growing organizations. We analyzed a four‐wave panel dataset from 267 establishments in South Korea and found that higher usage of HPWS at a prior point in time and increasing usage of HPWS over time led to consistently improved labor productivity when the employment size of establishments continued to grow. Our theory and findings provide new insight into the dynamic fit between HPWS and organizational performance over time in growing organizations. [ABSTRACT FROM AUTHOR]

The spatial and spectral properties of entangled photons from spontaneous parametric down-conversion (SPDC) with a focused pump are investigated with theoretical analysis and numerical simulation. Here, the spatial and spectral properties of down-converted photons are fully calculated without using the transverse momentum conservation assumption. We have obtained the spatial and spectral properties of SPDC photons under focused pumping in various SPDC configurations, including type-I, type-II for both positive and negative uniaxial crystals. Our result not only helps to understand the effect of pump focusing in SPDC better but also can find use in application of SPDC in realizing quantum information protocols. [ABSTRACT FROM AUTHOR]

The aleocharine subtribe Homalotina Heer represents one of the most diverse lineages of Staphylinidae. Despite its wide distribution and diversity, the phylogenetic relationships of the subtribe remain poorly understood. Here, we present the first cladistic analysis of the Homalotina based on morphological data. The subtribe is hypothesized to be a monophyletic group consisting of seven genera ( Anomognathus Solier, Cephaloxynum Bernhauer, Holisomimus Cameron, Homalota Mannerheim, Neomalota Cameron, Stenomastax Cameron, and Thecturota Casey). The dataset for phylogenetic analysis comprised 83 characters representing 245 character states derived from adult morphology. These data were analysed using equal weighting and implied weighting schemes ( k = 1-6) and results support the monophyly of the subtribe based on two synapomorphic characters (complete postoccipital sutures on head, posterolateral margin of metacoxae with macrosetae) and three homoplastic characters (medial setae on prementum not extended to apex of ligula, medial setae on labium contiguous, posterolateral angle of elytron slightly sinuate). Generic relationships differ in each analysis within the Homalotina ( EW, IW with k = 1, 2-4, 5-6) although there are some identical topologies among the IW trees. Clades A, B, C, D, H, J and G were resolved as monophyletic in all weighting regimes. The monophyly of the genera is relatively well supported except for the genera Homalota and Stenomastax. Homalota species were recovered in four independent clades (clade C, D, I, K) and the Stenomastax species were recovered in two independent lineages. Candidates for the possible new genera are discussed. We herein transfer Homalota flavomaculata Bernhauer to the genus Stenomastax, resulting in the new combination [ Stenomastax flavomaculata (Bernhauer)]. Our preliminary character correlation tests using phylogenetic pairwise comparisons did not support the hypothesis of association between flattened body form, and subcortical habitat and anterior shift of antennal insertion in Homalotini. [ABSTRACT FROM AUTHOR]

This article proposes a direct approach for the prediction of inverter efficiency using MATLAB/Simulink, instead of an indirect loss calculation approach based on analytical models. In analytical approach, efficiency is obtained by calculating individual losses separately, such as switching losses, conduction losses and harmonic losses using analytical models. However, this approach requires accurate analytical models and complicated calculations, due to the variation in the switching frequency, switching transient and modulation techniques. In the proposed approach, the actual waveform of the inverter system is directly generated using MATLAB/Simulink. The instantaneous voltage and current waveform including switching transients are generated. Thus, the proposed approach is very simple and convenient for efficiency prediction. The proposed approach also works for any system parameters or control methods, such as various pulse-width modulation (PWM) techniques, different switching frequencies, switching devices and load types. The proposed approach can be adopted for the efficiency prediction of any switching strategies and any types of inverters such as neutral-point-clamped (NPC) inverters, H bridge inverters and H5 topology, since the topologies are modelled as circuits in the MATLAB/Simulink program and no analytical model is required for the proposed approach. Furthermore, the proposed approach can provide operation techniques and conditions such as PWM techniques and switching frequency that offer high efficiency. In this article, inverter performance is evaluated for various PWM techniques and switching frequencies. The PWM technique and switching frequency that offer high efficiency is obtained. Finally, the proposed approach is verified by experimental results. [ABSTRACT FROM PUBLISHER]

Three new species of the mycophagous aleocharine genus Gyrophaena Mannerheim are described in Korea. The types and paratypes of the new species are designated. Illustrations of the diagnostic characters and habitus photographs of new species are provided with a key to Korean species of Gyrophaena. [ABSTRACT FROM AUTHOR]

In this article, a contactless power transfer system using a series–series–parallel resonant converter (SSPRC) is proposed. The proposed converter can improve on or eliminate the disadvantages of the contactless system based on conventional resonant converters, since it independently compensates for a primary side leakage inductance, a secondary side leakage inductance and a magnetising inductance. The proposed converter also reduces the circulating currents and the reactive power by controlling the phase angle difference between the inverter output voltage and the current. In addition, the system design can be simplified, since the voltage gain is determined only by the transformer turns ratio for the overall load range without being affected by the other transformer parameters. The proposed converter is analysed with respect to the gain and current margin. The system design procedure is then described for the proposed circuit based on the circuit analysis. Finally, the experimental results are presented in order to verify the proposed contactless power supply. [ABSTRACT FROM PUBLISHER]

In this paper, a rectangular contactless transformer is proposed to be used in a contactless power supply system. The proposed rectangular contactless transformer maintains a high coupling coefficient even when it has a relatively large air gap. The characteristics of the proposed transformer are compared to a transformer using a general EE core with a variable air gap. The proposed system is verified through simulation and experimental results. The experimental results demonstrate that the efficiency of the contactless power transmission system using a contactless transformer based on a rectangular core is over 20% greater than the system based on the EE core. [ABSTRACT FROM AUTHOR]

A taxonomic study of Korean Myrmecopora Saulcy is presented. Myrmecopora ( Lamproxenusa) rufescens (Sharp) previously reported by Ahn was an incorrect identification of M. ( L.) reticulata Assing. Diagnoses, habitus photographs and line drawings of diagnostic characters are provided. [ABSTRACT FROM AUTHOR]

Abstract: We report methods for preparation and tomographic reconstruction of an arbitrary single-photon path qubit. The arbitrary single-photon path qubit is prepared losslessly by passing the heralded single-photon state from spontaneous parametric down-conversion through variable beam splitter. Quantum state tomography of the single-photon path qubit is implemented by introducing path-projection measurements based on the first-order single-photon quantum interference. Using the state preparation and path-projection measurements methods for the single-photon path qubit, we demonstrate preparation and complete tomographic reconstruction of the single-photon path qubit with arbitrary purity. [Copyright &y& Elsevier]

Three staphylinid species, Aleochara ( Aleochara) coreana Bernhauer, A. ( Coprochara) verna Say and Prosthecarthron sauteri Raffray, are recorded for the first time from South Korea. Redescriptions and line drawings of diagnostic characters of all three species are provided. Ecological notes are provided for P. sauteri. [ABSTRACT FROM AUTHOR]

Abstract: We report - Ga2O3/diamond-like carbon (DLC) core–shell heterostructure nanowires fabricated by vapor–liquid–solid method and radio frequency plasma enhanced chemical vapor deposition (PECVD). As-synthesized - Ga2O3 nanowires have widths of 30–150 nm and outer shell DLC thickness was in the range of 20–30 nm. The products were examined by scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersed spectrometry (EDS). In addition, outer DLC layer was confirmed by Raman spectroscopy, which shows typical two Raman bands at 1550 cm−1 (G peak) and 1330 cm−1 (D peak) corresponding to disordered graphite peak. [Copyright &y& Elsevier]

Abstract: We report a scalable linear optical scheme for generating entangled states of multiple ququarts in which the individual single-ququart state is prepared with the biphoton polarization state of frequency-nondegenerate spontaneous parametric down-conversion. The output state is calculated with the full consideration of the higher order effect (double-pair events) of spontaneous parametric down-conversion. Scalability to multiple-ququart entanglement is demonstrated with examples: linear optical entanglement of three and four individual biphoton ququarts. [Copyright &y& Elsevier]

Abstract: We report a practical non-postselection entanglement concentration scheme in which a maximally entangled Bell-state photon pair is produced from two pairs of partially (or non-maximally) entangled photons. Since this scheme is built only upon linear optical elements and does not require photon-number resolving detectors, it has immediate applications in experimental implementations of various quantum information protocols which require two-photon Bell-states. [Copyright &y& Elsevier]

We report an experiment which conclusively demonstrates that the two-photon entangled state interference cannot be pictured as the overlap and ‘bunching’ of two individual photons on a beamsplitter. We also demonstrate that photon ‘bunching’ does not occur if the two-photon Feynman amplitudes are distinguishable, even though individual photons do overlap on a beamsplitter. [Copyright &y& Elsevier]

This paper describes two different systems which can compensate harmonic currents generated in a power system. As non-linear loads increase gradually in industry fields, harmonic current generated in the electric power network system also increase. Harmonic currents make power network currents distorted and generate heat, vibration and noise in the power machinery. Many approaches have been applied to compensate harmonic currents generated in the power system. Among various approaches, in this paper, two approaches are compared and evaluated. They are flywheel compensators based on wounded rotor induction motor and squirrel cage induction motor. Both systems have a common structure. They use a flywheel as an energy storage device and use pulse width modulation inverters. The main differences are the size and rating of the converter used. [Copyright &y& Elsevier]

The quantum state of the photon pair generated from type-II spontaneous parametric downconversion pumped by an ultrafast laser pulse exhibits strong decoherence in its polarization entanglement, an effect which can be attributed to the clock effect of the pump pulse or, equivalently, to distinguishing spectral information in the two-photon state. Here, we propose novel temporal and spectral engineering techniques to eliminate these detrimental decoherence effects. The temporal engineering of the two-photon wavefunction results in a universal Bell-state synthesizer that is independent of the choice of pump source, crystal parameters, wavelengths of the interacting photons and the bandwidth of the spectral filter. In the spectral engineering technique, the distinguishing spectral features of the two-photon state are eliminated through modifications to the two-photon source. In addition, spectral engineering also provides a means for the generation of polarizationentangled states with novel spectral characteristics: the frequency-correlated state and the frequency-uncorrelated state. [ABSTRACT FROM AUTHOR]

By using the quantum teleportation protocol, Alice can send an unknown quantum state (e.g. the polarization of a single photon) to Bob without ever knowing about it. This paper discusses a quantum teleportation experiment in which nonlinear interactions are used for the Bell state measurement. Since the Bell state measurement is based on nonlinear interactions, all four Bell states can be distinguished. Therefore, teleportation of a polarization state can occur with certainty, in principle. Details of the theory and the experimental set-up are discussed. [ABSTRACT FROM AUTHOR]

Investigates several electrical models for the batteries. Electrical models of the battery; Ideal model; Linear model; Thevenin model; System analysis with battery characteristics; Conclusions.

Background and Aims: Endoscopic ultrasonography (EUS) is a useful diagnostic modality for evaluating gastric mesenchymal tumors; however, differentiating gastrointestinal stromal tumors (GISTs) from benign mesenchymal tumors such as leiomyomas and schwannomas remains challenging. For this reason, we developed a convolutional neural network computer-aided diagnosis (CNN-CAD) system that can analyze gastric mesenchymal tumors on EUS images. Methods: A total of 905 EUS images of gastric mesenchymal tumors (pathologically confirmed GIST, leiomyoma, and schwannoma) were used as a training dataset. Validation was performed using 212 EUS images of gastric mesenchymal tumors. This test dataset was interpreted by three experienced and three junior endoscopists. Results: The sensitivity, specificity, and accuracy of the CNN-CAD system for differentiating GISTs from non-GIST tumors were 83.0%, 75.5%, and 79.2%, respectively. Its diagnostic specificity and accuracy were significantly higher than those of two experienced and one junior endoscopists. In the further sequential analysis to differentiate leiomyoma from schwannoma in non-GIST tumors, the final diagnostic accuracy of the CNN-CAD system was 75.5%, which was significantly higher than that of two experienced and one junior endoscopists. Conclusions: Our CNN-CAD system showed high accuracy in diagnosing gastric mesenchymal tumors on EUS images. It may complement the current clinical practices in the EUS diagnosis of gastric mesenchymal tumors. [ABSTRACT FROM AUTHOR]

Since improvement of wireless communication, IP based mobility management protocols have been studied to provide seamless communication and mobility management. The vehicular ad hoc network (VANET) is one of mobility management protocols, especially providing seamless connection with inter/intra/inner vehicle communication. However, each vehicle moves fast that causes short-lived connections with Access Router (AR). Based on vehicles' characteristic, it is hard to provide the availability of IP services in VANET. The most critical issue of the design of scalable routing algorithm is to provide robustness of frequent path disruption caused by vehicles' mobility. In this paper, we pursue the characteristics of vehicles' mobility and analyze them. With the navigation information which is one of vehicles' mobility characteristics, we classify the mobility into intrahighway mobility and global mobility management. Furthermore, we propose mobility management scheme based on route prediction in VANET. Handoffs with intrahighway mobility are managed locally and transparency is provided to CHs, while global mobility is managed with Mobile IPv6. Finally, through the numerical analysis, we show that proposed mobility management protocol reduces handoff latency, signaling costs, and packet loss. [ABSTRACT FROM AUTHOR]

The genus Coenonica Kraatz in the tribe Homalotini Heer is composed of 154 species from the World and 38 species in the Palaearctic region. In East Asia, 17 species have been recorded from China and four species from Japan. In Korea, two species, Coenonica absurda Pace and C. lewisa (Sharp), have been recorded by Paśnik (2001) from North Korea. Members of the genus Coenonica are characterized by the combination of following features: body depressed, pronotum with a U or V-shaped impression, meso- and metaventral processes rounded or truncate apically. During an ongoing study of the Korean Homalotini, we found four Coenonica species. Coenonica absurda Pace and C. lewisa (Sharp) are reported for the first time in South Korea, and C. sharpi (Fauvel) and C. zhejiangensis Pace from the Korean peninsula. We provide a key to the species of Korean Coenonica and illustrations of habitus photographs with line drawings of diagnostic characters. The specimens studied are deposited in the Chungnam National University Insect Collection (CNUIC, Daejeon), Korea. [ABSTRACT FROM AUTHOR]

While collecting the Korean seashore Staphylinidae, we found unusual rove beetles under decaying seaweeds along beaches of the southern coasts. As a result of the detailed study of them, we identified them as Heterota onorum Maruyama, new to Korean fauna. Heterota Mulsant and Rey contains 11 species worldwide and one species ( H. sunjaei) in Korea, all members of which are confined to coastal habitat and usually found under decaying seaweeds on rocky shore or sandy beach. The genus can be recognized by the combination of following characters: broad occiput; prominent eyes; narrow and long ligula; labial palpi with two articles; transverse pronotum; tarsal formula 4-4-5. In this study, we present a habitus photographs, diagnosis, illustrations of diagnostic characters, and distributional map of the species. [ABSTRACT FROM AUTHOR]

Objective: Particulate matter (PM), which contains organic compounds and toxic metals, is the major cause of air pollution. PM enters the body, causing various health problems. Although the effects of PM on the lower respiratory tract have been extensively investigated, the effects on the upper respiratory tract (including the nasal cavity) require further evaluation. To investigate the effect of fluticasone propionate (FP) on nasal fibroblasts exposed to UPM.Methods: Samples of inferior turbinate tissue were obtained from six patients. The fibroblasts isolated from these samples were exposed to UPM and/or FP. The expression of interleukin (IL)-6, CXC chemokine ligand (CXCL) 1, IL-1β, and tumour necrosis factor-alpha (TNF-α) in nasal fibroblasts was analysed using real-time PCR and enzyme-linked immunosorbent assays. The protein levels of nuclear factor kappa B (NF-κB) and signal transducer and activator of transcription 3 (STAT3) were analysed by western blotting.Results: FP reversed the UPM-induced reduction in cell viability. The mRNA and protein levels of IL-6, CXCL1, IL-1β, and TNF-α were significantly increased by UPM. FP reversed the UPM-induced increases in the protein levels of NF-κB and phosphorylated-STAT3 in a dose-dependent manner. In addition, TNF-α, an inducer of NF-κB, reversed the FP-induced reduction in the levels of signalling molecules.Conclusion: UPM induces the expression of IL-6, CXCL1, IL-1β, and TNF-α in nasal fibroblasts and this effect is reversed by FP via the STAT3 and NF-κB signalling pathways. These results suggest that FP has therapeutic potential for nasal diseases related to UPM, such as allergic and chronic rhinitis. [ABSTRACT FROM AUTHOR]

Nonlinear optical interactions can be enhanced dramatically by tight light-confinement and long interaction-length. Optical fiber tapers with micro/nano-thickness waists considerably increase light-matter interactions in or near their waists. Here, we propose and demonstrate a novel tapering method of fabricating uniform, low-loss, and ultra-long micro/nano fibers. The technique comprises three steps for conventional flame-brushing and pulling, recalibration, and one-directional pulling. Using the proposed method, two strands of tapered fibers are fabricated, having 0.82-μm/1.6-μm diameters, 220-mm/500-mm uniform lengths with <55-nm/66-nm diameter variances, and high transmittances of 90.2%/91.5%. A figure of merit indicating the nonlinear-optic efficiency is defined and used to compare the results obtained in this study with those for tapered fibers in references. The proposed tapering method will be very useful for the fabrication of tapered fiber devices exploiting nonlinear optic effects, including Brillouin scattering, Raman amplification, and other third-order nonlinearities for supercontinuum generation. [ABSTRACT FROM AUTHOR]

Background: When gastric mesenchymal tumors (GMTs) measuring 2–5 cm in size are found, whether to undergo further treatment or not is controversial. Endoscopic ultrasonography (EUS) is useful for the evaluation of malignant potential of GMTs, but has limitations, such as subjective interpretation of EUS images. Therefore, we aimed to develop a scoring system based on the digital image analysis of EUS images to predict gastrointestinal stromal tumors (GISTs). Methods: We included 103 patients with histopathologically proven GIST, leiomyoma or schwannoma on surgically resected specimen who underwent EUS examination between January 2007 and June 2018. After standardization of the EUS images, brightness values, including the mean (Tmean), indicative of echogenicity, and the standard deviation (TSD), indicative of heterogeneity, in the tumors were analyzed. Results: Age, Tmean, and TSD were significantly higher in GISTs than in non-GISTs. The sensitivity and specificity were almost optimized for differentiating GISTs from non-GISTs when the critical values of age, Tmean, and TSD were 57.5 years, 67.0, and 25.6, respectively. A GIST-predicting scoring system was created by assigning 3 points for Tmean ≥ 67, 2 points for age ≥ 58 years, and 1 point for TSD ≥ 26. When GMTs with 3 points or more were diagnosed as GISTs, the sensitivity, specificity, and accuracy of the scoring system were 86.5%, 75.9%, and 83.5%, respectively. Conclusions: The scoring system based on the information of digital image analysis is useful in predicting GISTs in case of GMTs that are 2–5 cm in size. [ABSTRACT FROM AUTHOR]

BACKGROUND: Maximum intensity projection (MIP) is a volume rendering technique that determines the pixel intensity as the maximum of all values sampled along the viewing direction. MIP has been successfully applied to diagnose bone fractures in computed tomography (CT) and the stenosis of vascular structures in magnetic resonance angiography (MRA). However, MIP has a major drawback in that the depth and occlusion information cannot be perceived in the output images. The most universal way to alleviate this problem is to occasionally change the viewpoint for depth perception. To support this function in real time, MIP should be performed at an interactive frame rate.OBJECTIVE: We develop an efficient rendering algorithm for MIP so that MIP is performed at an interactive frame rate without a loss of image quality.METHODS: The proposed method predicts the position of the maximum intensity for each ray using blockwise maximum bounds, after which it performs bidirectional compositing toward both ends of the ray from this predicted position. During the compositing process, block skipping is used as an acceleration method.RESULTS: The proposed method outperformed the block skipping method using the sequential compositing with a speed-up factor of 2.2 &nvsim; 2.8 depending on the data set without any degradation of the image quality.CONCLUSION: We proposed an efficient rendering technique for MIP. Our method was superior to the conventional block skipping method with respect to the rendering speed and degree of performance consistency. [ABSTRACT FROM AUTHOR]

In pulsed power system, mechanical characteristic means the structure of the plasma reactor, and impedance matching between the pulse generator and the plasma reactor means the electrical characteristics. It is a very important issue in the industry because impedance matching is closely related to the efficiency and reliability of the pulsed power system. In this paper, the design and implementation for improving the energy density of the wire-plate plasma reactor are presented. The system configuration, impedance characteristics and structures of the plasma reactor are described, and the output characteristic of the plasma reactor according to the structure of the wires and plates is analyzed. The plasma reactor model is realized on the simulation tool, and the simulation results are compared with the experiment data. Based on the theoretical analysis and the simulated model, impedance matching between the wire-plate plasma reactor and the pulsed power generator can be more fully achieved. [ABSTRACT FROM AUTHOR]

Capacitor charging power supply (CCPS) is a developed technology that utilizes resonant converters topology for high power applications. This paper proposes new a capacitor charging power supply using leg-rotation control method within a phase-shifted PWM full-bridge dc/dc converter. The capacitor charging power supply was connected in series to increase output voltage. Also, the proposed system is designed with soft switching techniques in order to achieve high efficiency, and a leg-rotation control method was used to reduce the heat generated from the IGBTs. The operation of the converter and design methodology will be described. A simplified model of a high-voltage high-frequency transformer is given and the structure is designed to decrease high-voltage stress. The validity of the proposed system is then verified by experimental results. The performance test of the capacitor charging power supply was carried out with a 2 μF capacitive load with a 20 kV output voltage. [ABSTRACT FROM AUTHOR]

In high-voltage systems such as in pulse power, commonly used semiconductor devices cannot be applied to the generation part of high-voltage pulse. However, unlike semiconductor, the magnetic switch cannot control its own ON and OFF operation. Moreover, with the magnetic switch the system efficiency goes down with load variation, and arcs caused by saturation of the energy in reactor have a negative effect on the whole system. This letter presents the way to effectively control the magnetic switch applied to high-voltage pulse power supplies such as plasma generators. The efficiency of the system is optimized by automatically controlling the magnetic switch based on the load variation. Then, the energy the load requires is supplied to the system, which leads to the stability of the system. The proposed method is confirmed by experiments on a designed system. [ABSTRACT FROM AUTHOR]

Decoherence, often caused by unavoidable coupling with the environment, leads to degradation of quantum coherence. For a multipartite quantum system, decoherence leads to degradation of entanglement and, in certain cases, entanglement sudden death. Tackling decoherence, thus, is a critical issue faced in quantum information, as entanglement is a vital resource for many quantum information applications including quantum computing, quantum cryptography, quantum teleportation and quantum metrology. Here, we propose and demonstrate a scheme to protect entanglement from decoherence. Our entanglement protection scheme makes use of the quantum measurement itself for actively battling against decoherence and it can effectively circumvent even entanglement sudden death. [ABSTRACT FROM AUTHOR]

We report operation and characterization of a lab-assembled single-photon detector based on commercial silicon avalanche photodiodes (PerkinElmer C30902SH, C30921SH). Dark count rate as low as 5 Hz was achieved by cooling the photodiodes down to -80 °C. While afterpulsing increased as the photodiode temperature was decreased, total afterpulse probability did not become significant due to detector's relatively long deadtime in a passively-quenched scheme. We measured photon detection efficiency >50% at 806 nm. [ABSTRACT FROM AUTHOR]

Abstract: We report experimental verification of the commutation relation for Pauli spin operators using the single-photon polarization state. The experimental quantum operation corresponding to the commutator, , showed process fidelity of 0.94 compared to the ideal operation and is determined to be . [ABSTRACT FROM AUTHOR]

We investigate light absorption in metal films, silver and aluminum, with different surface roughness. Measurements using an integrating sphere show that the reflectance in silver decreases significantly with increasing surface roughness whereas the reflectance in aluminum is almost constant. The experimental results agree well with numerical simulations in which the surface roughness of metal is described properly. In particular, the simulations demonstrate that the absorption by surface-plasmon-polaritons excited on a rough silver surface causes the surface-dependent reflectance in silver. This study suggests a convenient and feasible rule to rationally design a backside metal reflector toward high-efficiency light-emitting diodes and photovoltaics. [ABSTRACT FROM AUTHOR]