• 제목/요약/키워드: Rogers

검색결과 161건 처리시간 0.026초

Substrate-integrated-waveguide cavity-backed circularly polarized antenna with enhanced bandwidth and gain

  • Shankaragouda M. Patil;Rajeshkumar Venkatesan
    • ETRI Journal
    • /
    • 제46권3호
    • /
    • pp.404-412
    • /
    • 2024
  • We propose a method for increasing the bandwidth of a substrate-integrated-waveguide (SIW) cavity-backed antenna with taper-based micro-strip SIW transition feeding. For radio transmission, a circular slot is etched on top of the SIW cavity. For optimal antenna design, the slot is etched slightly away from the cavity center to generate circularly polarized waves. Simulations show a wide axial ratio bandwidth of 7.860% between 11.02 GHz and 11.806 GHz. Experimental results confirm a similar wide axial ratio bandwidth of 4.9% between 10.8 GHz and 11.35 GHz. An SIW feed from an inductive window excites the radiating circular slot, resulting in a simulated wide impedance range of 1.548 GHz (10.338 GHz-11.886 GHz) and bandwidth of 13.93%. Experimental results show a wide impedance of 2.08 GHz (10.2 GHz-12.08 GHz) and bandwidth of 18.84%. The SIW cavity-backed antenna creates a unidirectional pattern, leading to gains of 6.61 dBi and 7.594 dBi in simulations and experiments, respectively. The proposed antenna was fabricated on a Rogers RT/Duroid 5880 substrate, and the reflection coefficient, radiation patterns, and gains were tested and compared using a computer simulator. The developed broadband antenna seems suitable for X-band applications.

A Study on Influencing factors and strategic market segmentation for diffusing ATCA based network equipments (ATCA 기반 통신 장비의 수요 요인 분석 및 도입 전략에 관한 연구)

  • Yoo Jae-heung;Ha Im-sook;Choi Mun-kee
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • 제30권7B호
    • /
    • pp.450-463
    • /
    • 2005
  • This paper aims to find influencing factors for firms to adopt network equipments which based on Advanced Telecom Computing Architecture (ATCA). ATCA suggests a standardized specification for telecom equipments design. This new paradigm of developing network equipment provides benefits for network equipment manufacturers by reducing development time for new equipments with lower CapEx and OpEx. It also deliver oportunities for telecom services providers to exploit or test new services by replacing or upgrading part of total system with modular based network equipments. The research model basically depends on various researches based on Rogers' Innovation and Diffusion theory and it is verified through an empirical study for ninety-one domestic forms. Binary logistic regression was conducted to find the relationship between purchase intention and factors affecting new technology adoption. As a result, two factors such as scalability and cost/benefit effectiveness of the new system were statistically significant. Cluster analysis followed with those two variables. This helps TEMs (Telecom Equipments Manufacturers) get some implications on timing and target customers for diffusing the ATCA based technologies in the market.

Findings from the Survey Responses by Cambodian Doctors and Patients for Telemedicine (캄보디아 환자와 의사의 원격 의료에 대한 반응 조사)

  • Yoo, Sun-gil;Oh, Dongik;Min, Sedong;Shin, Wonhan
    • Journal of Internet Computing and Services
    • /
    • 제16권4호
    • /
    • pp.13-23
    • /
    • 2015
  • In order to reduce public medical expenses as well as to provide effective medical services, telemedicine between doctors and patients is considered as an alternative to the conventional hospital visit. But the medical community has been protesting the introduction of telemedicine for the efficacy and safety reasons. Korean government has been conducting a number of pilot projects to demonstrate the efficacy and safety of telemedicine for more than 10 years. However, still the system is not yet legalized. In this study, we have conducted a telemedicine pilot project in Cambodia for one year, where telemedicine can be more freely exercised. After the project, we conducted a survey based on the 'Rogers diffusion' theory. Survey results show that both physicians and patients are positive about the relative advantage of the telemedicine. However, the complexity and high cost of the equipment used in telemedicine has been found to be a possible obstacle. In addition, we found that there is no problem for providing telemedicine services under challenged environment, such as in Cambodia.

Clinical Factors Associated with the Non-Operative Airway Management of Patients with Robin Sequence

  • Albino, Frank P.;Wood, Benjamin C.;Han, Kevin D.;Yi, Sojung;Seruya, Mitchel;Rogers, Gary F.;Oh, Albert K.
    • Archives of Plastic Surgery
    • /
    • 제43권6호
    • /
    • pp.506-511
    • /
    • 2016
  • Background The indications for surgical airway management in patients with Robin sequence (RS) and severe airway obstruction have not been well defined. While certain patients with RS clearly require surgical airway intervention and other patients just as clearly can be managed with conservative measures alone, a significant proportion of patients with RS present with a more confusing and ambiguous clinical course. The purpose of this study was to describe the clinical features and objective findings of patients with RS whose airways were successfully managed without surgical intervention. Methods The authors retrospectively reviewed the medical charts of infants with RS evaluated for potential surgical airway management between 1994 and 2014. Patients who were successfully managed without surgical intervention were included. Patient demographics, nutritional and respiratory status, laboratory values, and polysomnography (PSG) findings were recorded. Results Thirty-two infants met the inclusion criteria. The average hospital stay was 16.8 days (range, 5-70 days). Oxygen desaturation (<70% by pulse oximetry) occurred in the majority of patients and was managed with temporary oxygen supplementation by nasal cannula (59%) or endotracheal intubation (31%). Seventy-five percent of patients required a temporary nasogastric tube for nutritional support, and a gastrostomy tube placed was placed in 9%. All patients continued to gain weight following the implementation of these conservative measures. PSG data (n=26) demonstrated mild to moderate obstruction, a mean apneahypopnea index (AHI) of $19.2{\pm}5.3events/hour$, and an oxygen saturation level <90% during only 4% of the total sleep time. Conclusions Nonsurgical airway management was successful in patients who demonstrated consistent weight gain and mild to moderate obstruction on PSG, with a mean AHI of <20 events/hour.

A Study on the Perceived characteristics of the mobile payment service using the technology acceptance model (기술수용모델을 활용한 모바일 소액결제 시스템의 인지적 특성 분석)

  • 이석기;김성희
    • Journal of the Korea Society of Computer and Information
    • /
    • 제9권1호
    • /
    • pp.103-109
    • /
    • 2004
  • Mobile payment service is a new innovating technology in the micro payment industry. Although it emerged only one or two years a9o in Korea, it is now highly used and prospered by many online companies. Traditional studies concerning the electronic payment system are usually about the payment process itself, so they stressed the security or the robustness of the process. The study from the angle of behavioral science seldom exists. This article describes the phenomenon of technology adoption with a particular focus on telephone Payment service. The article identifies which characteristic of the telephone payment service affects to the user status (user, non-users). To do this, this article mainly used Roger's Technology Acceptance Model and some characteristics are added to the model. The most important perceptual characteristic that affects to the user status was not security, but ease of use-the telephone payment service had to enhance continuously for the competitive advantage over the other payment service. Observability and convenience are also noted as important.

  • PDF

Evolutionary Concept Analysis of Korean Cancer Survivors' Happiness (한국 암생존자의 행복감에 대한 진화론적 개념분석)

  • Cho, HyeKyung;Song, MiSoon
    • Journal of the Korea Convergence Society
    • /
    • 제9권8호
    • /
    • pp.365-377
    • /
    • 2018
  • The purpose of the study was to analyze the concept of happiness that would be experienced in life of Korean cancer survivors. The concepts of happiness were analyzed using the Rogers' evolutionary concept analysis method for 11 papers satisfying the selection criteria, among domestic journals published from January 2000 to September 2017. The result of this study was that attributes of happiness were subjective experience, positive mind, meaning of life and formation of relationship. Antecedents were to accept-risk-of-life, cope-with-the-reality, implement-self-reflection and environmental-support. As a result of the concept, cancer survivors' inner strength increased, they became feeling love and pursuing new lives, and felt happiness through self-realization. This study is valuable to suggest a basic framework for the stepwise assessment that can improve the happiness of Korean cancer survivors and cancer survivors should be managed through multidisciplinary convergence programs.

A Comparative Study of Korean and British Consumers for the Diffusion of Green Fashion Products (그린패션제품 확산을 위한 한국과 영국 소비자 비교 연구)

  • Lee, Jieun;Sung, Heewon
    • Journal of the Korean Society of Clothing and Textiles
    • /
    • 제36권10호
    • /
    • pp.1087-1099
    • /
    • 2012
  • This study investigated the purchase intention of green fashion products based on Rogers' Diffusion of Innovation theory and compared the differences between Korean and British consumers. In order to identify the impact of personal characteristics, this study also examined the effects of fashion innovativeness and LOHAS tendency on perceived attributes of innovation and intention to purchase. With a convenience sampling method, a survey questionnaire was distributed at popular fashion streets in each country. A total of 426 data were obtained, 203 from the UK and 223 from Korea. About 52% were females, and 69% were in their twenties. A factor analysis generated two LOHAS factors (health concerns and eco concerns) and four attributes of green fashion products (image improvement, symbolic superiority, observability, and compatibility). Two types of green fashion products (organic cotton t-shirts and organic cotton t-shirts with an environmental message) were provided to measure the purchase intention, respectively. The findings were as follows. British consumers were more likely to show LOHAS tendency and to perceive positive advantages of green products compared to Koreans; in addition, British consumers presented higher mean scores on the purchase intentions of organic cotton products. Fashion innovativeness was significant to predict image improvement and symbolic superiority, while eco concerns were significant in compatibility for both nations. Compatibility was important for both countries in order to explain the intention to adopt two types of organic products. In addition, image improvement was another predictor for purchase intention of organic t-shirts with an environmental message. Managerial implications were provided.

Systematic study on the genus Corbicula (Bivalvia : Corbiculidae) in Korea (한국산 재첩속(Corbicula) 이매패류의 계통분류학적 연구)

  • 이준상;김종범
    • Animal Systematics, Evolution and Diversity
    • /
    • 제13권3호
    • /
    • pp.233-246
    • /
    • 1997
  • A genetic analysis using starch gel electrophoresis was performed to clarify the degrees of genetic differentiation and the phylogenetic relationships among four species of the genus Corbicula (Bivalvia, Corbiculidae). The average genetic similarity coefficients among the populations of each species on C. fluminea, C. leana and C. colorata were very closed (Rogers' S$\geq$0.970), whereas the other C. japonica was separated into two genetic groups (S=0.873) with distinct allelic difference at the Gpl locus. Thuefore additional taxonomic studies are needed on this species. On the other hand, these four species were well distinguished from each other genetically with distinct allelic differences at 4 to 9 loci. The genetic similarity coefficients (S) between C. leana and C. colorata, C. fluminea and C. leana, and C. fluminea and C. colorata were 0.737, 0.689, and 0.594, respectively. In particular, the average genetic similarity coefficients between these three species (inhabiting in freshwater) and the other C. japonica (inhabiting in brackishwater) were notably lower (S=0.370).

  • PDF

A Study on the Characteristics of Exhibition Space Organization of the Museum's Typology on Served and Servant Space Type - Focused on Renzo Piano's Work Influenced by Louis I. Kahn's Characteristics of Exhibition Space Organization - (뮤지엄건축에 있어서 분리형 전시공간구성 특성에 관한 연구 - 루이스 칸의 전시공간구성방법의 영향을 받은 렌조 피아노의 작품분석을 중심으로 -)

  • Lee, Sung-Hoon;Park, Yong-Hwan
    • Korean Institute of Interior Design Journal
    • /
    • 제15권5호
    • /
    • pp.238-246
    • /
    • 2006
  • Renzo Piano was first introduced to us when he got together with Richard Rogers and won the Grand Prize on Center George Pompidou Competition in Paris. Since then, he designed number of world renowned museum architecture such as Menil Collection & Museum, The Cy Twombly Gallery, Beyeler Foundation Museum, and most recently the New Pavilion of High Museum of Art. His museum design, in particular, showed very consistent feature which is differentiating the 'Served Space(exhibition area) and the Servant Space(service core or mechanical system area)'. In addition, the way he treats natural light as a special feature within his museum space was nicely done and it is remarkable both in design and engineering side; he always designed a very unique roof structure system to give life and to simulate emotion of light within the space. These are just a few points of his special design characteristics which differentiate him from the rest of the architect working today. While interested by works of Renzo Piano, we found that his work had very close relationship to Louis I. Kahn's design. Specially the way Renzo Piano differentiating serving and servant space and the way he treating natural light. Therefore, the purpose of study is focused on providing typology of museum exhibition organization as well as finding evidence of Louis I. Kahn's influence and concept he has shown in his museum projects through actual site visits and reference research. The method of research was as the following; first to find typology and its characteristics of exhibition space organization of all Renzo Piano's museum projects. Secondly to distinguish projects which show 'differentiated servant and served space'. As the result of this study, it was clear that Renzo Piano had influence of Louis I. Kahn on adopting 'Servant and Served Space' concept. But the research concluded with the facts to approve the uniqueness of Renzo Piane's design concept.

A Study on the Proximity of Cosmetic to Self by Self-Efficacy (자기효능감(自己效能感)에 따른 화장근접도(化粧近接度)에 관(關)한 연구(硏究))

  • Jo, Ki-Yeu;Yoo, Tai-Soon
    • Journal of Fashion Business
    • /
    • 제3권1호
    • /
    • pp.104-112
    • /
    • 1999
  • The purpose of this study was to examine the proximity of cosmetic to self by self-efficacy. The scales used in this study include the scale of Sherer, Mercadante, Maddux, Rrentice-Dunn, Jacobs and Rogers(1982) for general and social self-efficacy, the scale of Ryckman, Roddins, Thorton, and Cantrell(1982) for physical self-efficacy, and the scale developed by the researcher for proximity of cosmetic to self. The subjects of this study were 885 adult women in Taegu. The data collected were analyzed by using MANOVA, ANOVA, and the Cronbach $\alpha$ reliability was also applied. The results of this study were summarized as follows: The persons with high general self-efficacy showed high degrees of joy of change in the sub-factors of proximity of cosmetic to self, while there was no difference in social confidence, skin care, self-satisfaction and instrument of disguise between persons with high general self-efficacy and those with low general self-efficacy. In addition, the persons with high social self-efficacy showed high degree of social confidence, skin care, joy of change, self-satisfaction and instrument of disguise in the sub-factors of proximity of cosmetic to self. And the persons With high physical self-efficacy had high degrees of joy of change and disguise. In the sub-factors of proximity of cosmetic to self, while there was no difference in the social confidence, skin care, self-satisfaction between persons with high physical self-efficacy and those With low physical self-efficacy.

  • PDF