• 한국벤처창업학회:학술대회논문집
• /
• 2019.11a
• /
• pp.51-59
• /
• 2019

현대사회가 당면한 다양한 문제를 해결하는 주체로 '제4섹터(the fourth sector)'가 주목받고 있다. 제4섹터는 사회적경제 기업으로 대표되는 제3섹터의 지나친 정부 의존도와 서비스 모델 동형화의 문제점을 해결하고자 등장하였다(Meadows, 1972; Howaldt and Schwarz, 2010). 이러한 제4섹터의 핵심 주체로서 소셜벤처가 언급되고 있다(경기연구원, 2018). 그러나 아직까지 소셜벤처에 대한 학술적 및 정책적 개념이 모호한 실정이다. 따라서 본 연구에서는 사회의 포용적 성장을 도모하기 위해 제4섹터로서의 소셜벤처 정의와 특성을 명확히 하고, 소셜벤처 생태계 활성화를 위한 발전전략을 연구하고자 한다.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2009.11a
• /
• pp.471-472
• /
• 2009

여러 개의 섹터에 존재하는 안테나들로부터 협력적으로 신호를 전송 받는 다수의 사용자를 시간축에서 선택하는 스케쥴러의 성능을 시스템 전체 성능과 평등성 지표의 관점에서 개선하기 위하여 섹터 간의 협력을 고려할 수 있다. 기존 스케쥴러는 단일 셀에서의 사용자를 선택하는 방식으로 평등성 지표의 향상만을 고려하였으나 제안하는 섹터 간 협력 비례적 평등 스케쥴러는 동시 전송 사용자들 간의 채널의 직교성을 고려함으로써 시스템 전체 성능과 하위 사용자의 성능을 개선할 수 있다. 본 논문에서는 총 3 개의 인접한 섹터로 이루어진 분산 다중 안테나 시스템에 스케쥴러를 적용하고 그 성능을 분석한다. 섹터 간 협력 비례적 평등 스케쥴러는 각 섹터에 존재하는 사용자들의 채널 직교성을 활용하는 동시에 채널 변화 속도가 빨라짐에 따른 다이버시티 효과를 이용하여 시스템 전체 성능을 크게 향상시킨다. 또한 이 방식은 하위 사용자 성능이 우수한 수정된 협력 최대-최소 평등 스케쥴러의 하위 사용자 성능의 최고 99%의 성능을 달성한다.

• The Proceeding of the Korean Institute of Electromagnetic Engineering and Science
• /
• v.8 no.3
• /
• pp.40-47
• /
• 1997

안테나의 특성은 셀룰러 시스템의 서비스 품질에 직접적으로 영향을 미치는 요소가 되며, 특히 섹터화로 인한 용량의 증가를 기할 수 있는 CDMA 시스템의 경우에는 매우 중요한 의미를 갖는다. 본 논문의 지향성 안테나를 이용하여 전력 제어된 CDMA 셀을 섹터화할 경우 얻을 수 있는 용량의 이득을 논의한다. 용량의 측면에서 이상적인 안테나 패턴과 비교할 때 실제 안테나 패턴의 역방향 링크 용량 효율을 해석적으로 구한다. 셀룰러 CDMA 시스템의 용량은 동일한 주파수 대역을 사용할 수 있는 최대 통신 채널의 수이므로 용량 효율은 결국 주파수 스펙트럼 이용 효율을 의미한다. 측정된 반사판 섹터 안테나 패턴을 대상으로 분석한 결과를 제시하고 패턴 특성과 섹터 셀의 배치 구조에 따라 용량 효율이 86~97%로 변화함을 보인다.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2008.05a
• /
• pp.693-697
• /
• 2008

Generally, the rate of reuse should be increased within the certain area for efficient operation of radio resources in a CDMA mobile communication system, and then signal interference between the sane radio channels should be minimized. for this reason, this study conducted a simulation of cell secterization methods(3 and 4 sectors) as a practical and immediately applicable method to the field to minimize signal interference, to construct an economical network, and to increase the efficiency of frequency use. Also, by analyzing RSSi, $E_c/I_o$, $E_b/N_t$ and 3-way handoff which were simulation results, their possibility of use was identified.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
• /
• v.15 no.3
• /
• pp.1-17
• /
• 2020

The Fourth Sector has been attracting attention as a means to solve the various problems plaguing modern society; it emerged to overcome the Third Sector's issues such as excessive reliance on the government and service model isomorphism, represented by social economy enterprises (Meadows, 1972; Howaldt & Schwarz, 2010). Social venture companies have been mentioned as key agents of the Fourth Sector (Gyeonggi Research Institute, 2018). However, the academic and policy concepts related to social ventures continue to be vague. Therefore, this study aims to clarify the concept of social ventures as part of the Fourth Sector, and research development strategies for the vitalization of the social venture ecosystem in an effort to encourage inclusive growth of society. To achieve these goals, it establishes the concept of social ventures differentiated from the Third Sector, based on previous studies, and presents the importance of an intermediate support organization for the ecosystem's vitalization. Furthermore, to propose strategies for said vitalization, the study derives detailed forms of social venture intermediate support organizations, and provides suggestions regarding their importance and roles through social innovation levels.

• The Journal of the Korea institute of electronic communication sciences
• /
• v.4 no.3
• /
• pp.211-216
• /
• 2009

Chattering phenomenon is still a large drawback of VSS. To overcome this problem, various approaches have been reported. A new notion of sliding sector has been proposed recently. In this paper, fuzzy control with time-varying boundary layer using the sliding sector theory with continued input function in the sector is proposed. This paper analyzes the stability, using Lyapunov function on the sliding sector. Computer simulation for inverted pendulum results in elimination of the chattering phenomenon.

• The Journal of the Korea institute of electronic communication sciences
• /
• v.2 no.3
• /
• pp.168-173
• /
• 2007

Chattering phenomenon is still a large drawback of VSS. To overcome this problem, various approaches have been reported. A new notion of sliding sector has been proposed recently. In this paper, new methods of the nonlinear system control using the sliding sector theory with continued input function in the sector is proposed. This paper analyzes the stability, using Lyapunov function on the sliding sector. computer simulation for inverted pendulum results in elimination of the chattering phenomenon.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.18 no.12
• /
• pp.2816-2822
• /
• 2014

In this paper, a wideband loop antenna for UWB applications is studied. The structure of the proposed wideband loop antenna is a circular loop antenna with appended circular sectors to obtain an ultra-wideband characteristic. The circular sectors are used instead of conventional triangular sectors to match with the 50 ohm feed line. Optimal design parameters are obtained by analyzing the effects of the gap between the circular sectors and the radius of the circular loop on the input reflection coefficient and gain characteristics. The optimized wideband loop antenna is fabricated on an FR4 substrate with a dimension of 41 mm by 41 mm. Experiment results show that the proposed antenna has a frequency band of 3.1-11.0 GHz for a VSWR < 2.25, which assures the operation in the UWB band. Measured gain ranges 1.3-5.3 dBi in the UWB band.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.36 no.7B
• /
• pp.818-826
• /
• 2011

This paper proposes a novel FTL (Flash Translation Layer) algorithm employing sector-level mapping technique based on locality to reduce the number of erase operations in flash memory accesses. Sector-level mapping technique shows higher performance than other mapping techniques, even if it requires a large mapping table. The proposed algorithm reduces the size of mapping table by employing dynamic table update, processes sequential writes by exploiting sequential locality and extracts hot sector in random writes. Experimental results show that the number of erase operations has been reduced by 75.4%, 65.8%, and 10.3% respectively when compared with well-known BAST, FAST and sector mapping algorithms.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.10 no.2
• /
• pp.303-312
• /
• 2009

In this paper, we design and fabricate a disk sector antenna fed by CPW fur UWB communications. Also, we insert a rectangular slit on the arc-edge of the disk sector antenna. Then, the antenna has the directivity of E-면. In order to design the antenna, the input impedance is matched with the feed line of $50{\Omega}$ as varying the physical antenna parameters, which are the radius, the flare angle of disk sector, the length of ground, and the length of ground comer near by feed tine. Dimension of the antenna designed for UWB communication is $72mm{\times}26mm$ and bandwidth through computer simulation is $3{\sim}13GHz$. From the measured results, the bandwidth is $1.98{\sim}11GHz$. Return loss and gain of the fabricated antenna are -50.38dB, 1.34dBi at 3.5GHz, -12.27dB, 3.35dBi at 5.5GHz, -23.2dB, 3.8dBi at 8GHz and -16.17dB, 5.2dBi at 10GHz, respectively.