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South Korea's mortgage loan policy, which represents a regulatory policy for stabilizing the housing market, has changed significantly in accordance with changes in presidency and partisanship. Which partisan government's housing policy has been most effective in stabilizing the market? To answer this question, we discuss the different partisanships of Korea's conservative and progressive parties, their policy preferences, and the previous governments' key housing policies. Thereafter, we concretize the research methodology and examine the housing volatility witnessed since 1987, using the Markov-switching regression. The results reveal that the market was highly unstable when the progressive government actively promoted regulation in favor of "governmentalist" partisanship. Moreover, the policy was mostly effective in lowering apartment prices in Seoul, which was the regulation's primary target all along. Based on these findings, we conclude with some policy implications of the study. Given that governmentalist partisanship heightens volatility in the housing market, housing market policies should be designed to hedge the negative externalities of partisanship. [ABSTRACT FROM AUTHOR]

The propagation of spin waves in magnetically ordered systems has emerged as a potential means to shuttle quantum information over large distances. Conventionally, the arrival time of a spin wavepacket at a distance, d, is assumed to be determined by its group velocity, vg. Here, we report time-resolved optical measurements of wavepacket propagation in the Kagome ferromagnet Fe3Sn2 that demonstrate the arrival of spin information at times significantly less than d=vg. We show that this spin wave "precursor" originates from the interaction of light with the unusual spectrum of magnetostatic modes in Fe3Sn2. Related effects may have far-reaching consequences toward realizing long-range, ultrafast spin wave transport in both ferromagnetic and antiferromagnetic systems. [ABSTRACT FROM AUTHOR]

Graphene oxide, which exhibits extraordinary acidic properties and a high theoretical surface area, is a good candidate for the catalytic transformation of biomass resources to valuable chemicals and biofuels. In this study, graphene oxide was prepared through various graphite oxide exfoliation methods, including sonication, microwave irradiation, and freeze-thaw cycling, and the activity of the prepared catalysts was evaluated in the saccharification of cellulose. The results indicated that graphene oxide prepared via these methods exhibited superior catalytic performances compared to graphite oxide; however, no significant difference in the catalytic activity of the graphene oxide catalysts was observed based on the exfoliation method used. Therefore, we proposed that thinning of graphite oxide improves its catalytic activity by increasing the contact efficiency between the substrate and the catalyst; however, this is not dependent on the exfoliation method used to prepare the graphene oxide. [ABSTRACT FROM AUTHOR]

In 2009, Korea implemented a law school educational system, which not only changed the legal education system, but the legal landscape as a whole. This has led to rapid growth in the number of attorneys. Although the increased number of attorneys has resulted in lower barriers to accessing justice, it has also brought the unintended consequence of cut-throat competition. With the number of disciplinary actions rising by four-fold in the last three years, the current version of the Korean Code of Ethics for Attorneys is certainly a step in the right direction but may not be enough to strengthen attorneys' legal ethics in such an unprecedented time in Korean legal history. In light of the heated discussion in Korea regarding legal ethics, this comment, following the accompanying translation of the Korean Bar Association's Code of Ethos for Attorneys, first, analyzes how the Korean legal education system and legal ethics education has changed over time. Second, to provide context on how the current Code of Ethics reached its current form, this comment reviews the history of and recent amendments to the Code of Ethics. Lastly, it considers next steps for the Code of Ethics and how attorneys can have a better sense of legal ethics in the long term. This comment is for those interested in comparative legal ethics, Korean legal ethics, and the Korean legal system. [ABSTRACT FROM AUTHOR]

For local homing navigation, an agent is supposed to return home based on the surrounding environmental information. According to the snapshot model, the home snapshot and the current view are compared to determine the homing direction. In this paper, we propose a novel homing navigation method using the moment model. The suggested moment model also follows the snapshot theory to compare the home snapshot and the current view, but the moment model defines a moment of landmark inertia as the sum of the product of the feature of the landmark particle with the square of its distance. The method thus uses range values of landmarks in the surrounding view and the visual features. The center of the moment can be estimated as the reference point, which is the unique convergence point in the moment potential from any view. The homing vector can easily be extracted from the centers of the moment measured at the current position and the home location. The method effectively guides homing direction in real environments, as well as in the simulation environment. In this paper, we take a holistic approach to use all pixels in the panoramic image as landmarks and use the RGB color intensity for the visual features in the moment model in which a set of three moment functions is encoded to determine the homing vector. We also tested visual homing or the moment model with only visual features, but the suggested moment model with both the visual feature and the landmark distance shows superior performance. We demonstrate homing performance with various methods classified by the status of the feature, the distance and the coordinate alignment. [ABSTRACT FROM AUTHOR]

A number of landmark-based navigation algorithms have been studied using feature extraction over the visual information. In this paper, we apply the distance information of the surrounding environment in a landmark navigation model. We mount a depth sensor on a mobile robot, in order to obtain omnidirectional distance information. The surrounding environment is represented as a circular form of landmark vectors, which forms a snapshot. The depth snapshots at the current position and the target position are compared to determine the homing direction, inspired by the snapshot model. Here, we suggest a holistic view of panoramic depth information for homing navigation where each sample point is taken as a landmark. The results are shown in a vector map of homing vectors. The performance of the suggested method is evaluated based on the angular errors and the homing success rate. Omnidirectional depth information about the surrounding environment can be a promising source of landmark homing navigation. We demonstrate the results that a holistic approach with omnidirectional depth information shows effective homing navigation. [ABSTRACT FROM AUTHOR]

The dynamic characteristics of III-nitride multi-quantum well laser diodes (LDs) emitting at 410 nm were investigated. LDs were grown on semipolar (20¯2¯1¯) bulk GaN substrates and fabricated into devices with cavity lengths ranging from 900 nm to 1800 nm. A 3-dB bandwidth of 5GHz and 5 Gbit/s direct modulation with on-off keying were demonstrated, which were limited by the bandwidth of the photodetector used for the measurements. The differential gain of the LDs was determined to be 2.5±0.5 ×10-16 cm2 by comparing the slope efficiency for different cavity lengths. Analysis of the frequency response showed that the K-factor, the gain compression factor, and the intrinsic maximum bandwidth were 0.33 ns, 7.4 × 10-17 cm3, and 27 GHz, respectively. Published [ABSTRACT FROM AUTHOR]

For sequential stacking of an Al2O3 passivation layer and a main HfO2 gate dielectric layer on In0.53Ga0.47As, we used single- and dual-temperature atomic-layer deposition processes, and systematically compared their effects on the dielectric-related electrical properties. When the deposition of Al2O3 passivation layer (approximately 0.7−0.8 nm) took place at relatively low temperatures of 100 °C, an increase in the subsequent deposition temperature for HfO2 (from 100 to 300 °C) assisted in decreasing both capacitance-equivalent oxide thickness and the number of bulk-related traps. However, the valuable reduction in both near-interface defect density and leakage current through the low-temperature Al2O3 passivation approach was monotonically lessened with an increase in the process temperature for the subsequent HfO2 deposition, which suggests the need for a careful optimization of a thermal budget for the dual-temperature process. [ABSTRACT FROM AUTHOR]

The number of atomic layer deposition (ALD) cycles for ZnO treatment was changed to study its merits and demerits as a passivation layer prior to the deposition of a HfO2 film on a p-type In0.53Ga0.47As substrate. Even a few cycles of ZnO ALD treatment was effective in improving the capacitance–voltage (C–V) characteristics by suppressing strong Fermi-level pinning, which occurred because of a high interface state density near the lower half of the In0.53Ga0.47As band gap. Increases in the number of ZnO ALD cycles induced an increase in the minimum capacitance and response of minority carriers at higher frequencies in the inversion region of the C–V characteristics. According to various temperature- and frequency-dependent C–V analyses, these changes were explained by the shallow p-type doping effect of Zn atoms in the In0.53Ga0.47As substrate. As a disadvantage, ZnO ALD treatment caused a slight increase in the dielectric leakage current. [ABSTRACT FROM AUTHOR]

The effectiveness of trimethylaluminum (TMA) and tetrakis(dimethylamido)titanium (TDMAT) pretreatments on GaSb substrates were compared by examining the interfacial and capacitance–voltage (C–V) characteristics of Al2O3/p-type GaSb capacitors. In addition, for sample preparation, the temperature-dependent surface reactivity of GaSb was confirmed by examining the impact of the atomic layer deposition (ALD) loading temperature (stand-by temperature in air). An increase in the loading temperature from 65 to 150 °C in air ambient degraded the interfacial and C–V properties, which confirms the importance of the processing temperature for GaSb-based devices. Both in situ TMA and TDMAT pretreatments at 65 °C prior to the ALD of Al2O3 (150 °C) were effective in decreasing the amount of the interface oxide and the interface state density. While a similar degree of frequency dispersion in the C–V accumulation region was observed in the ALD-Al2O3/GaSb capacitor samples with and without TMA pretreatment, it largely increased for the TDMAT-pretreated sample, probably due to the formation of a Ti-oxide interlayer. [ABSTRACT FROM AUTHOR]

A multilayer thin film antenna for mobile devices is proposed. The proposed antenna consists of a (indium–zinc–tin oxide) IZTO/Ag/IZTO multilayer film, which is fabricated on a polyimide substrate (εr = 3.5) and a copper layer. The centre frequency of the antenna is 1260 MHz. The geometry of the antenna is made up of a coupled loop and two branches. The proposed antenna was fabricated using the DC pulse sputter instrument. The measured and simulated results of the antenna are given. The measured peak gain of the proposed antenna is 1.66 dBi. The transparency of the IZTO/Ag/IZTO thin film on the polyimide substrate is 86%. The advantages of the proposed antenna are high transparency, low resistivity and flexibility. [ABSTRACT FROM AUTHOR]

The excitonic insulator is an electronically driven phase of matter that emerges upon the spontaneous formation and Bose condensation of excitons. Detecting this exotic order in candidate materials is a subject of paramount importance, as the size of the excitonic gap in the band structure establishes the potential of this collective state for superfluid energy transport. However, the identification of this phase in real solids is hindered by the coexistence of a structural order parameter with the same symmetry as the excitonic order. Only a few materials are currently believed to host a dominant excitonic phase, Ta2NiSe5 being the most promising. Here, we test this scenario by using an ultrashort laser pulse to quench the broken-symmetry phase of this transition metal chalcogenide. Tracking the dynamics of the material's electronic and crystal structure after light excitation reveals spectroscopic fingerprints that are compatible only with a primary order parameter of phononic nature. We rationalize our findings through state-of-the-art calculations, confirming that the structural order accounts for most of the gap opening. Our results suggest that the spontaneous symmetry breaking in Ta2NiSe5 is mostly of structural character, hampering the possibility to realize quasi-dissipationless energy transport. [ABSTRACT FROM AUTHOR]

Amorphous Ti1−xAlxOy films in the Ti-oxide-rich regime (x  <  0.5) were deposited on p-type GaAs via atomic layer deposition with titanium isopropoxide, trimethylaluminum, and H2O precursor chemistry. The electrical properties and energy band alignments were examined for the resulting materials with their underlying substrates, and significant frequency dispersion was observed in the accumulation region of the Ti-oxide-rich Ti1−xAlxOy films. Although a further reduction in the frequency dispersion and leakage current (under gate electron injection) could be somewhat achieved through a greater addition of Al-oxide in the Ti1−xAlxOy film, the simultaneous decrease in the dielectric constant proved problematic in finding an optimal composition for application as a gate dielectric on GaAs. The spectroscopic band alignment measurements of the Ti-oxide-rich Ti1−xAlxOy films indicated that the band gaps had a rather slow increase with the addition of Al-oxide, which was primarily compensated for by an increase in the valance band offset, while a nearly-constant conduction band offset with a negative electron barrier height was maintained. [ABSTRACT FROM AUTHOR]

Experiments were conducted to measure the performance of direct-current-pulsed electrohydrodynamic drop formation as a function of liquid viscosity, electrical conductivity, and surface tension. While hydrodynamic and charge relaxation times and Taylor cone formation frequencies suggest theoretical drop-generation frequencies well in excess of 100Hz, we show that it is impossible to produce more than 50 drops per second with performance decreasing as viscosity increased or electrical conductivity decreased (and not a significant function of surface tension). Instead of relying on relaxation-time calculations to predict the maximum, reliable dropproduction frequency, a dimensionless coefficient that is a function of viscosity and electrical conductivity is proposed to estimate the fulcrum frequency. [ABSTRACT FROM AUTHOR]