Korea Communications Commission

Abstract Subminiature GPSL1band (center frequency: 1575 MHz, wavelength []: 190 mm) microstrip antenna suitable for mounting in small electronic devices is proposed in this paper. The newly proposed antenna was transformed from the basicλ/2 microstrip patch antenna to aλ/4 microstrip antenna. To apply the perturbation theory, the width of the radiating element on the feeding point with strong magnetic field energy was narrowed. In addition, the open end of the radiating element with strong electric field energy was folded down in a “王” shape to reduce the antenna size. The size of the designed subminiature microstrip antenna is 10 mm (0.05) × 9.5 mm (0.05) × 8.5 mm (0.04). For impedance matching, the position of the feeding point and the gap between the feeding line and the short stub were adjusted. The fabricated antenna obtained of −17 dB at the center frequency of 1575 MHz. While the size of the ground plane was 48 mm (0.25λ) × 50 mm (0.26λ), the omnidirectional radiation characteristics for both in thexz‐plane andxy‐plane with average gain of −0.3 and −1.7 dBi, respectively. A size reduction ratio of 98.9% was secured from the results compared to the basicλ/2 microstrip patch antenna.

The use of social media, such as social networking sites and instant messaging, in everyday life continues to spread, along with social media use in the workplace. This study examined how using social media like Facebook (social networking sites) and KakaoTalk (instant messaging) at work affects individual job performance. It also analyzed whether social media use has different effects on individual job performance depending on the characteristics of the given task. The results demonstrated that both Facebook and KakaoTalk had linearly positive effects on individual job performance. Moreover, task equivocality had a positive moderating effect on the relationship between KakaoTalk use and job performance. The results may have significant implications for firms reviewing their policies on employees’ social media use. Since using social media such as Facebook and KakaoTalk in the workplace improves job performance, firms may consider encouraging employees toward this practice. In particular, they may consider supporting those employees who perform tasks with high task equivocality in making use of instant messaging platforms.

In this letter, we present a method for improving the front-to-back ratio (FBR) of a broadcast antenna. The digitalization of terrestrial TV demands more efficient channel usage due to the reduction in TV bands after the switch-over. Thus, we designed an antenna with an FBR improved over -45dB as compared to the -20 to -25dB FBR range of existing antennas. We show experimentally that this antenna satisfies the required performance.

PurposeThe purpose of this paper is to reveal the core determinants and adoption patterns of the major enterprise information systems.Design/methodology/approachThis study incorporated the core representative and meaningful explanatory variables in the major previous literatures and analyzes the core determinants of businesses' adoption of the essential information systems and the substitutionary patterns among them, using a Bayesian multivariate probit model, which is based on McFadden's random utility model and capable of handling multiple response data.FindingsIt was found that not only factors from the classical technological diffusion viewpoint but also factors such as organizational tools and strategic behaviors play an important role in firms' adoption of information systems. Specifically, epidemic effect generally outweighs size effect, and putting more effort into the intensity of information strategy planning is more influential than the hiring of a professional chief information officer. On the other hand, such variables as age of the firm, labor intensity, and number of PCs per person generally have no significant impacts. Finally, a relatively strong complementary relationship exists between enterprise resource planning and customer relationship management adoption, and between e‐buy and groupware adoption.Originality/valueThe results presented in this paper have important implications for firms on a minimal budget that want to maximize their productivity through the adoption of information systems. They also provide important information for government policymakers whose job it is to design strategies for the successful deployment of information systems.

In this paper, we propose an experiment that assesses fusional response curve and eye-blink rate to measure visual fatigue induced by stereoscopic videos. A random dot stereogram was utilized to measure the reliable fusional limit and response curve acquired by determining the direction of Landolt C. The results were analyzed to discriminate the individual ability of 3D fusion and compared with the results of subjective evaluation and descriptive self-report. It shows that while watching 3D video, viewers who have slow fusional response and low fusional limits are more sensitive to visual fatigue. In addition, eye-blinks were measured using eye images captured by a camera. Eye-blinks were increased in the video with moderate visual fatigue than low visual fatigue and decreased more in the second half than the first half of the session.

Surface plasmon polaritons, as a surface electromagnetic wave, have plenty of features in the near-field zone. We find that not only localized SSPs but also magnetic plasmon resonance play a vital role in plasmonic electromagnetically induced transparency (EIT). Their interaction is investigated in detail by analyzing the phase evolution of the induced electromagnetic fields in nanoscale volume, which is rendered by the unique near-field properties and not the case in the far-field zone. Based on this picture, the plasmonic EIT controlled by a single optical field is suggested in a modified scheme for active plasmonic switching by simply adjusting the incident angle of the optical field. The tunability of plasmonic EIT in this scheme is exhibited sufficiently.

In this paper, a multi-band antenna is designed, and the effect of its near-zone field on the Hearing Aid is checked.