• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.23 no.9
• /
• pp.1019-1024
• /
• 2012

In this paper, a UWB antenna using a SIR(Step Impedance Resonator) that eliminate signal interference at 5 GHz WLAN as the first rejection band and adjust the second rejection band is proposed. Unlike the unit impedance resonator, the second harmonic of SIR is decided according to step impedance. Therefore, To adjust the second rejection band, SIR is applied to UWB antenna. Also, the equivalent circuit of the antenna at first rejection band is presented and the equivalent modeling values of the SIR and the coupling value is obtained. The proposed antenna is satisfied to cover full UWB band with return losses less than -10 dB and has band rejection characteristic in 5 GHz WLAN band. The radiation patterns show +y directivity characteristics in H-plane and the group delay variations are within 1.0 ns.

• Journal of the Economic Geographical Society of Korea
• /
• v.8 no.2
• /
• pp.195-215
• /
• 2005

This study was carried into execution to analyze Spatial Characteristics of Seoul Business Services Cluster in circumstance of local economic development led by knowledge-intensive business services. The analysis was performed for industrial agglomeration and companies' linkage and network. As the result, there are three business services cluster, including the largest one in Gang-Nam Gu, Seoul, and for last 10 years, there has been increasing development of business services cluster. In the meanwhile, their linkage and network have not been performed briskly. Therefore, from now on, a plan that can help companies' linkage and network performed inside of cluster to have active and international structure has to be considered in cluster policy.

• Journal of the Economic Geographical Society of Korea
• /
• v.21 no.3
• /
• pp.254-269
• /
• 2018

The aim of this paper is to identify the components of the sustainable regional ecosystem of social economy enterprises (hereafter 'regional ecosystem'), and to explore the principles of reciprocity, regard and public policy, which have a fundamental impact on the development of such regional ecosystem. The regional ecosystem is an interactive system of the stakeholders who are related to the process of planning, producing, distributing and selling goods and services, and the agents who maintain and spread their social value orientation. This system operates through the interaction of 'local network (business relations and social relations)', 'intermediary organization' and 'public role.' On the basis of the conceptual framework on the regional ecosystem, the result of the in-depth analysis on the case of Gorang-erang Coop shows the interaction of reciprocity and public policy with respect to regard within the context of a characteristic of the regional ecosystem.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.24 no.1
• /
• pp.36-46
• /
• 2013

This paper proposes the design of broadband spiral antenna for a potable non-linear junction detector (NLJD) system. To realize the broadband antenna design, it was considered optimization of the number of spiral turns by iteration calculation. Ground plane with the Archimedean spiral slit to keep the same current distribution between radiating plane and ground is considered for circular polarization design. In order to realize high directivity and high gain of the proposed antenna, the cavity wall and the metal cap which is located on back of ground plane were also considered in design. Measurement results of return loss were agreed well with VSWR 2:1 at interested frequency band among 2.4 to 2.44 GHz, 4.84 to 4.92 GHz and 7.28 to 7.36 GHz. Measured axial ratio was observed 3 dB below and showed reasonable agreement with simulation results. Characteristics of the RHCP(Right Hand Circular Polarization) with the measured gain of 6.8 dBi above at interested frequency band were also observed.

• Journal of Korean Academy of Nursing Administration
• /
• v.22 no.4
• /
• pp.396-405
• /
• 2016

Purpose: The study was done to investigate nurses' customer orientation, emotional labor, unit manager-nurse exchange and relational bonds and to identify the factors affecting nurses' turnover intentions. Methods: A cross-sectional survey was conducted using self-report questionnaires. The participants in this study were 276 nurses in tertiary hospital located in a metropolitan city, Korea. Data were analyzed using descriptive statistics, t-test, ANOVA, Pearson correlation coefficient and stepwise multiple regression with the SPSS program 22.0. Results: The mean scores were $3.74{\pm}0.90$ (out of 5) for turnover intention, $5.31{\pm}0.87$ (out of 7) for customer orientation, $4.82{\pm}0.96$ (out of 7) for emotional labor, $3.58{\pm}0.61$ (out of 7) for relational bonds, and $3.18{\pm}0.57$ (out of 5) for unit manager-nurse exchange. Factors influencing turnover intention were 'emotional labor' (${\beta}$=.39, p<.001), 'unit manager-nurse exchange' (${\beta}$=-.22, p<.001), 'financial bonds' (${\beta}$=-.19, p<.001), 'perceived economic status' (${\beta}$=-.15 p=.003) and 'career' (${\beta}$=.14, p=.005). These factors explained 34.9% of the variance in turnover intension (F=30.46, p<.001). Conclusion: Findings indicate that to reduce nurses' turnover intention in the hospital, there is a need to improve unit manager-nurse exchange and to manage strategies lowering nurses' emotional labor.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.14 no.12
• /
• pp.2642-2648
• /
• 2010

The design of coupling and rectifying circuits for the maritime VHF digital modem is investigated in this paper. To monitor the transmitting power of the modem, a directional coupler which is used to extract a small fraction of the transmitter signal power, and a rectifying circuit which make DC voltage proportional to the coupled rf power are designed and fabricated. The parallel-coupled line coupler with directivity of above 25 dB at 160 MHz bands is designed and it is shown that the output voltage of the rectifying circuit is linearly changing from 0.85 V to 1.6 V when the transmitting power of the modem is varying from 1 W to 25 W. The proposed coupler and rectifying circuits are expected to be suitable for maritime VHF digital modem.

• The Journal of the Acoustical Society of Korea
• /
• v.35 no.6
• /
• pp.436-444
• /
• 2016

Uniformity in transducer performance is a must-have to ensure the reliable acoustic performance of a tile projector, used for active echo reduction. However, practical limitations imposed by variations in material properties and fabrication errors lead to performance variations among unit transducers, which could degrade the radiation characteristics (transmitting voltage response and directivity) of the tile projector and ultimately the echo reduction performance. In this paper we present a method to minimize these adverse effects via an appropriate placement of unit transducers within the tile projector. To this end, we perform a series of coupled acoustic-piezoelectric simulations, assuming a group of 36 unit transducers having 6 dB variations in transmitting voltage response, to analyze and compare the radiation characteristics of tile projectors under different transducer placement schemes.

• Journal of Digital Convergence
• /
• v.11 no.11
• /
• pp.85-94
• /
• 2013

This paper presents a novel mobile measurement system with multi antennas which enable mobile measurement as well as fixed measurement with telescope mast. Proposed system installed 4 omni directional antennas for the space diversity process and one directional log periodic antenna for the simultaneous conventional fixed measurement. Whole antenna systems are connected to the custom DTV channel analyzers with Ethernet networks respectively and processed by the main controller to calculate real time average receive levels. To prove the performance of proposed system, the typical receive models are categorized as 3 area types - open area, building area and house area, and then intensive field tests were performed through mobile and fixed measurement phases. With these measurement data, the relationships between mobile and fixed measurement are analyzed, and the concept of compensation factor is proposed to assume the average receive level of signal. The field test is fulfilled as a co-work with public broadcasters and the proposed system is applied to the intensive coverage measurement projects for metropolitan areas by the korean government agencies.

• Journal of the Korea Society of Computer and Information
• /
• v.18 no.10
• /
• pp.183-192
• /
• 2013

This paper examines the impact of the strategic leadership of CEOs after M&A on resistance to change and on perceived performance. Most M&A research has focused on the strategic, financial and economic aspects, while studies on leadership and employee behavior have been limited. CEO leadership is critical to a successful M&A. Recently, strategic leadership has been attracting more attention. Strategic leadership can be defined as a person's ability to anticipate, envision, maintain flexibility, think strategically and to work with others to initiate changes that will create a viable future for an organization. It can also reduce resistance and improve perceived performance. So this paper used empirical studies from the IT industry after M&A.

• Journal of Service Research and Studies
• /
• v.5 no.2
• /
• pp.1-13
• /
• 2015

This study deduced an effect produced on the export performance of ICT company through precedent study. And the importance of each factor was analyzed, regarding the deduced influencing factors. And influencing factors in the export performance of ICT export companies were presented at a practical level on the basis of analysis results. According to the results of analysis, with regard to the influencing factor in the export performance of ICT company, companies' factors were interpreted as the most important influencing factor among the 1st hierarchical factors. According to the results of analysis after setting 12 factors for the 2nd hierarchical factor, 4 factors including export experience, CEO's market orientation, marketing strategy, and export market attractiveness were interpreted as very important factors. Therefore, it was possible to find that, with regard to the influencing factor in the export performance of ICT company, above all, enterprise internal factors- i.e., companies' factors, marketing factors- were more important influencing factors.