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A combination of the venturi module and the vortex cup was proposed to solve vortex instability and to enhance grip capacity. Mounting a venturi suction pad inside the vortex cup improved vacuum generation efficiency. When the vortex cup properly maintained the non-contact air gap and generated an equivalent vacuum to achieve a sealing effect around the open gap of the suction pad, the combined head improved grip capacity and stabilized the non-contact environment. Furthermore, the flow patterns around the venturi chamber and the swirl inside the vortex cup were analyzed based on the design elements of each module. In a module that integrated some of the venturi’s features internally, increased air consumption of the vortex cup was required than that of the venturi. However, it supported a wide range of non-contact grips. The coupled model effectively protected the vacuum suction features of the venturi suction pad in all non-contact environments in that range.

Background To investigate the surgical outcomes of implantable collamer lens (ICL) implantation in eyes with residual myopia after primary laser vision correction (LVC) surgeries. Methods This study included patients who underwent ICL implantation and had a history of LVC surgery, including photorefractive keratectomy (PRK) or laser-assisted in situ keratomileusis (LASIK). Visual acuity and refractive error were assessed pre and 3-months postoperatively and the efficacy and safety indices calculated accordingly. Results A total of 30 eyes of 17 patients were included in this study. At 3 months, the mean logMAR uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), and spherical equivalent were − 0.03 ± 0.11 (include logMAR), − 0.04 ± 0.09 (include logMAR), and − 0.06 ± 0.33 diopters (D), respectively. The 3-month Snellen UDVA was better than 20/20 for 83% of eyes, and 97% of eyes showed an unchanged or improved CDVA after surgery. The mean efficacy and safety indices were 1.11 ± 0.22 and 1.13 ± 0.20, respectively. Further, 93 and 100% of eyes were within ±0.5 and ± 1.0 D of the attempted spherical equivalent refraction, respectively. Conclusions ICL implantation in eyes with myopic regression after previous LVC surgery showed safe, effective, and predictable outcomes. Trial registration retrospectively registered.

In this article, a novel experimental characterization technique for coupled transmission lines fabricated on organic substrates is presented. The high-frequency characterizations of transmission lines fabricated on organic substrates are extremely difficult due to parasitic resonances. We eliminated the parasitic resonance effects by combining physical circuit models with experimental characterizations. The reconstructed coupled transmission-line parameters obtained using the proposed technique are compared from 10 MHz to 40 GHz with the measurement data using a vector network analyzer (VNA). The transmission-line parameters using S-parameter measurement data are too contaminated with external noise, whereas those using the proposed technique can effectively eliminate the parasitic effects.

In this article, a new experimental characterization technique for coupled transmission lines is presented. Three specific experimental test patterns (E-, F-, and G-type structures) that can individually characterize the electromagnetic coupling of two coupled lines are developed and fabricated on the same wafer using a 0.18- $\mu \text{m}$ CMOS process. Since the devised test patterns are two-port networks, well-established two-port network characterization techniques can be exploited. Transmission line model parameters (i.e., propagation constants and characteristic impedances) associated with the three two-port test patterns can be directly determined from the measured S-parameters, followed by circuit model parameters ( $R$ , $L$ , $C$ , and $G$ ) for two coupled lines. Without rigorous equipment calibration and deembedding parasitic effects, experimental characterizations for two coupled lines using four-port network S-parameter measurements may yield physically ambiguous data above 10 GHz due to the parasitic resonances, whereas the proposed technique can determine stable and accurate network parameters over a broad frequency band. To further support the validity of the proposed technique, they are compared with data using 3-D numerical calculations and low-frequency capacitance measurements.

The complex permittivity of mixed organic materials that are widely employed for micro-strip transmission lines is experimentally investigated. Micro-strip transmission line test patterns consisting of two different dielectric materials are fabricated on an organic substrate. In order to extract the complex permittivity over a broadband frequency, we determine the per-unit-length (PUL) capacitance and conductance with the S-parameters measured from 10 MHz to 40 GHz by using a vector network analyzer (VNA). In order to show the physical validity of the determined complex permittivity of mixed organic materials, we calculate the wave propagation factor and compare it with nominal and measured values. The complex permittivity characterized in this paper is shown to reflect accurately the loss of a transmission line at the high frequency.

In this paper, over a broad frequency band, a novel transmission line (TL) characterization method for highly-lossy miniaturized integrated circuit (IC) interconnect lines is presented. TLs fabricated on lossy organic substrates are difficult to characterize in a broad frequency band due to frequency-dependent losses and resonances. Test TLs are fabricated using a packaging process that employs an organic substrate and then characterized by using a vector network analyzer up to 40 GHz. TLs are modeled as a function of frequency by combining the modified skin effect model with experimental S-parameter data. Parallel admittance of TLs can be yielded by unifying the propagation constant with the frequency-variant resistance and inductance models, followed by TL characterization. It is verified that IC package interconnect lines can be reliably characterized up to high frequencies.

We study the critical energy dissipation in an atomic superfluid gas with two symmetric spin components by an oscillating magnetic obstacle. Above a certain critical oscillation frequency, spin-wave excitations are generated by the magnetic obstacle, demonstrating the spin superfluid behavior of the system. When the obstacle is strong enough to cause density perturbations via local saturation of spin polarization, half-quantum vortices (HQVs) are created for higher oscillation frequencies, which reveals the characteristic evolution of critical dissipative dynamics from spin-wave emission to HQV shedding. Critical HQV shedding is further investigated using a pulsed linear motion of the obstacle, and we identify two critical velocities to create HQVs with different core magnetization., Comment: 8 pages, 7 figures

Comparison of rectangular and hexagonal hogel printing for holographic stereogram printer based on integral imaging is presented. The hexagonal hogel printing is efficient than rectangular hogel printing and enhances the reconstruction image quality. Numerical simulation and optical reconstructions are implemented.

Purpose To investigate the surgical outcomes of immediate transepithelial photorefractive keratectomy (PRK) after suction loss during small-incision lenticule extraction (SMILE) and compare the outcomes with those of uneventful SMILE. Setting Eyereum Eye Clinic, Seoul, South Korea. Design Retrospective case series. Methods This study included 24 eyes of 12 patients who had uneventful SMILE in one eye and immediate transepithelial PRK after the development of suction loss during the lenticule cut in the contralateral eye. Visual acuity assessments, manifest refraction, and measurements of corneal wavefront aberrations were performed preoperatively and 6 months postoperatively. Results At 6 months, the mean uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), and spherical equivalent were -0.04 ± 0.05, -0.09 ± 0.05, and -0.02 ± 0.24 diopter (D), respectively, in the transepithelial PRK group and -0.10 ± 0.07, -0.06 ± 0.07, and -0.04 ± 0.17 D, respectively (P = .036, P = .109, and P = .671, respectively), in the uneventful SMILE group. The 6-month Snellen UDVA was better than 20/20 for 11 (92%) and 12 (100%) of eyes in the transepithelial PRK and uneventful SMILE groups, respectively. All 24 eyes showed unchanged or improved CDVA and a significant increase in the total corneal higher-order aberrations postoperatively. Corneal spherical aberrations exhibited a significant postoperative increase only in the transepithelial PRK group. Conclusions Immediate transepithelial PRK after early suction loss during SMILE might be safe and effective, with refractive outcomes that are comparable with those after uneventful SMILE.

We examine the effect of mandatory IFRS adoption on the information content of earnings announcement in Korea, and its main driving factors. We find an increase in earnings information content with...

This study examines the informational role of tax expense and deferred tax and investigates the fundamental determinants of their information content. Our theoretical and empirical analysis shows that the association between tax expense and stock returns after controlling for pre-tax profit should be determined by the difference in the information content between permanent book-tax differences and the other pre-tax profit. Empirical evidence is that the relatively lower informativeness of permanent differences results in the positive relation of tax expense to stock returns. In addition, the earnings persistence of permanent differences is lower than that of the other pre-tax profit, and various firm characteristics, including the composition of permanent differences, affect the information content of tax expense. In addition, it is a temporary book-tax difference that bases deferred tax in substance. Therefore, the control variable in a regression analysis for deferred tax should not include the temporary difference-related items. Using such a revised regression model, this paper shows that deferred tax expense (liability) has a positive association with stock returns (price), contrary to prior studies. Our study contributes to the literature through clarifying the underlying mechanisms behind the information content of tax expense items and providing new findings on their informational role. Particularly, this paper has implications for future study in that it provides a guideline for interpreting the relationship between the regression coefficients regarding tax expense accounts and improves the prior research methodology.

We investigate the early-time dynamics of a quasi-two-dimensional spin-1 antiferromagnetic Bose-Einstein condensate after a sudden quench from the easy-plane to the easy-axis polar phase. The post-quench dynamics shows a crossover behavior as the quench strength $\tilde{q}$ is increased, where $\tilde{q}$ is defined as the ratio of the initial excitation energy per particle to the characteristic spin interaction energy. For a weak quench of $\tilde{q}2$. The observed crossover behavior is found to be consistent with the Bogoliubov description of the dynamic instability of the initial spinor condensate., 7 pages, 6 figures

We study the propagation of sound waves in a binary superfluid gas with two symmetric components. The binary superfluid is constituted using a Bose-Einstein condensate of $^{23}$Na in an equal mixture of two hyperfine ground states. Sound waves are excited in the condensate by applying a local spin-dependent perturbation with a focused laser beam. We identify two distinct sound modes, referred to as density sound and spin sound, where the densities of the two spin components oscillate in phase and out of phase, respectively. The observed sound propagation is explained well by the two-fluid hydrodynamics of the binary superfluid. The ratio of the two sound velocities is precisely measured with no need for absolute density calibration, and we find it in quantitatively good agreement with known interaction properties of the binary system., 5 pages, 4 figures

This paper describes a green stripping process to effectively strip the remaining DFR layer on a non-alkali-based ITO glass surface after an etching process. A stripper, water-soluble amine compound, is used to investigate the characteristics of stripping ability and to suggest a valid method for the green process. Increasing the composition (5-30% concentration) of the ethanol amine-based stripper was found to greatly reduce the stripping time applied in the dipping method. The composition (30%) achieved an excellent stripping effect and free-residue impurities. Additionally, it was possible to obtain the effect of stripping in a way to sustain the release before generating DFR sludge from the ITO glass surface by using dipping condition (stripping time) in the composition. An Additional stripping process (buffering) out of dipping can realize productivity improvement and cost reduction because of the higher proportion of re-use of the stripping solution used in the DFR removal step.

A high-frequency fine-pitched (i.e., very narrow line width) thin-film transmission line (TL) characterization technique is presented. A new dielectric permittivity determination technique for thin-film TL structures is developed. Multi-layered mixed dielectric materials are then accurately characterized in a broad frequency band, to be followed by the TL characterization. For experiments, various lengths of TL and extra patterns were designed and fabricated by using both a ${\hbox{0.18-}}\mu{\hbox{m}}$ SK Hynix CMOS process and ${\hbox{0.13-}}\mu{\hbox{m}}$ Samsung CMOS process. S-parameters for the test patterns were measured by using a vector network analyzer from 10 MHz to 50 GHz. It is shown that not only the inherent de-embedding problems associated with wafer-level high-frequency characterizations can be conveniently eliminated, but also the frequency-variant characteristic impedance of a thin-film TL can be readily determined using the proposed technique. It can be exploited for accurate high-frequency wafer-level component characterizations including miniaturized transistors, frequency-variant interconnect lines, and other circuit components.

We investigate the stability of a hard-axis polar state in a spin-1 antiferromagnetic Bose-Einstein condensate under a magnetic field gradient, where the easy-plane spin anisotropy is controlled by a negative quadratic Zeeman energy $q, Comment: 8 pages, 7 figures

We investigate the phase transition dynamics of a quasi-2D antiferromagnetic spin-1 Bose-Einstein condensate from the easy-axis polar phase to the easy-plane polar phase, which is initiated by suddenly changing the sign of the quadratic Zeeman energy $q$. We observe the emergence and decay of spin turbulence and the formation of half-quantum vortices (HQVs) in the quenched condensate. The characteristic time and length scales of the turbulence generation dynamics are proportional to $|q|^{-1/2}$ as inherited from the dynamic instability of the initial state. In the evolution of the spin turbulence, spin wave excitations develop from large to small length scales, suggesting a direct energy cascade, and the spin population for the axial polar domains exhibit a nonexponential decay. The final equilibrated condensate contains HQVs, and the number is found to increase and saturate with increasing $|q|$. Our results demonstrate the time-space scaling properties of the phase transition dynamics near the critical point and the peculiarities of the spin turbulence state of the antiferromagnetic spinor condensate., Comment: 8 pages, 7 figures

This paper describes an improved design model that can be used to configure a non-contact pneumatic device to turn a large sheet at the in-line system. For rotational moving in the conveyor system, the conventional method is to turn the system itself. The improved non-contact pick-up system mainly uses 8 pairs of L-shaped latches and 12 swirl type heads. It is positioned above the upward air flow table. This system performs the non-contact gripping and side-edge contact support in the vertical and rotational directions to hold the self-weight of a large flat sheet. A non-contact air head can exert a sufficient gripping ability at 4N lower than the standard working pressure. The side latches support 60% of the lifting force required. Through structural and flow analysis, the working conditions were simultaneously considered in accordance with the deflection and flatness of the glass.Received 5 September 2014Revised 8 October 2014Accepted 10 October 2014

This paper presents an applicable basic design that can configure non-contact levitation table for conveying a large sheet of glass. The suggested air levitation table consists of a series of air chambers with porous pads and fans as the conveyor system. The air supply chambers are arrayed to supply an adequately strong upward airflow for supporting the glass. Levitation is controlled by the size and discharge velocity, of the chamber arrays, as well as the glass supporting height. After pre-evaluation of the glass rigidity and the filer functional performance, a one-way fluid structure interface (FSI) analysis is performed for predicting pressure and deflection working of the 8G glass in the transverse and longitudinal directions, respectively. After comparing calculated levels of flatness of the glass, it determines the chamber array for the linear non-contact conveying motion.

This paper describes an improved model that can be used for configuring a non-contact pneumatic head to handle a large sheet of glass. The cylindrical head model is of a large size (70 mm). It operates on vortex flow, which can simultaneously generate suction and repulsion over the flat object`s surface. The head allows for the minimal non-contact lifting of objects weighing over 3N by using reference conditions (working pressure and head dimensions). Additionally, a functional flow-guide is applied for inducing a developing tangential vortex flow to increase suction and repulsion to the reference head. The cylindrical flow-guide is associated with relatively low tangential velocity. The improved model generates greater lifting force than the reference model, as verified experimentally.