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Between the City and Images:An Analysis of Mainstream Media’s Paths of Constructing the Cultural Memory of a City:Taking Chengdu Radio and Television’s“Hi Chengdu”as an Example 被引量:1
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作者 Ding Ran Shi Lei 《Contemporary Social Sciences》 2024年第2期97-111,共15页
Mainstream media play a crucial role in constructing the cultural memory of a city.This study used 319 short videos released by“Hi Chengdu,”a new media product of Chengdu Radio and Television,as samples.Based on the... Mainstream media play a crucial role in constructing the cultural memory of a city.This study used 319 short videos released by“Hi Chengdu,”a new media product of Chengdu Radio and Television,as samples.Based on the grounded theory,a research framework encompassing“content,technology,and discourse”was established to explore the paths through which mainstream media construct the cultural memory.Regarding content,this paper emphasized temporal and spatial contexts and urban spaces,delving deep into the themes of the cultural memory and vehicles for it.In terms of technology,this paper discussed the practice of leveraging audio/visual-mode discourse to stitch together the impressions of a city and evoke emotional resonance to create a“flow”of memory.As for discourse,this paper looked at the performance of a communication ritual to frame concepts and shape urban identity.It is essential to break free from conventional thinking and leverage local culture as the primary driving force to further boost a city’s productivity,in order to excel in cultural communication. 展开更多
关键词 the cultural memory of a city short videos the grounded theory Chengdu Radio and television “Hi Chengdu”
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Standard-definition White-light,High-definition White-light versus Narrow-band Imaging Endoscopy for Detecting Colorectal Adenomas:A Multicenter Randomized Controlled Trial
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作者 Chang-wei DUAN Hui-hong ZHAI +10 位作者 Hui XIE Xian-zong MA Dong-liang YU Lang YANG Xin WANG Yu-fen TANG Jie ZHANG Hui SU Jian-qiu SHENG Jun-feng XU Peng JIN 《Current Medical Science》 SCIE CAS 2024年第3期554-560,共7页
Objective This study aimed to compare the performance of standard-definition white-light endoscopy(SD-WL),high-definition white-light endoscopy(HD-WL),and high-definition narrow-band imaging(HD-NBI)in detecting colore... Objective This study aimed to compare the performance of standard-definition white-light endoscopy(SD-WL),high-definition white-light endoscopy(HD-WL),and high-definition narrow-band imaging(HD-NBI)in detecting colorectal lesions in the Chinese population.Methods This was a multicenter,single-blind,randomized,controlled trial with a non-inferiority design.Patients undergoing endoscopy for physical examination,screening,and surveillance were enrolled from July 2017 to December 2020.The primary outcome measure was the adenoma detection rate(ADR),defined as the proportion of patients with at least one adenoma detected.The associated factors for detecting adenomas were assessed using univariate and multivariate logistic regression.Results Out of 653 eligible patients enrolled,data from 596 patients were analyzed.The ADRs were 34.5%in the SD-WL group,33.5%in the HD-WL group,and 37.5%in the HD-NBI group(P=0.72).The advanced neoplasm detection rates(ANDRs)in the three arms were 17.1%,15.5%,and 10.4%(P=0.17).No significant differences were found between the SD group and HD group regarding ADR or ANDR(ADR:34.5%vs.35.6%,P=0.79;ANDR:17.1%vs.13.0%,P=0.16,respectively).Similar results were observed between the HD-WL group and HD-NBI group(ADR:33.5%vs.37.7%,P=0.45;ANDR:15.5%vs.10.4%,P=0.18,respectively).In the univariate and multivariate logistic regression analyses,neither HD-WL nor HD-NBI led to a significant difference in overall adenoma detection compared to SD-WL(HD-WL:OR 0.91,P=0.69;HD-NBI:OR 1.15,P=0.80).Conclusion HD-NBI and HD-WL are comparable to SD-WL for overall adenoma detection among Chinese outpatients.It can be concluded that HD-NBI or HD-WL is not superior to SD-WL,but more effective instruction may be needed to guide the selection of different endoscopic methods in the future.Our study’s conclusions may aid in the efficient allocation and utilization of limited colonoscopy resources,especially advanced imaging technologies. 展开更多
关键词 standard-definition white-light endoscopy high-definition white-light endoscopy narrow-band imaging colonoscopy colorectal cancer screening adenoma detection rate
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Construction and Development of the National Experimental Teaching Demonstration Center for Drama and Film and Television Disciplines
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作者 Wei Zhou 《Journal of Contemporary Educational Research》 2024年第9期271-276,共6页
Taking the National Experimental Teaching Demonstration Center of the Central Academy of Drama as an example,this article explores the construction and development of the National Experimental Teaching Demonstration C... Taking the National Experimental Teaching Demonstration Center of the Central Academy of Drama as an example,this article explores the construction and development of the National Experimental Teaching Demonstration Center for the practical teaching of drama and film and television disciplines.The article first introduces the background and importance of the demonstration center and then analyzes in depth the construction content and achievements of the demonstration center from four aspects:practical teaching philosophy,practical teaching system,practical teaching resources,and practical teaching effects.Finally,the article summarizes the experience and shortcomings of the demonstration center and proposes future development directions and suggestions. 展开更多
关键词 Drama and film and television disciplines Practical teaching National Experimental Teaching Demonstration Center Central Academy of Drama
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Utilizing Microwave Technology in Radio and Television Transmitters 被引量:1
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作者 Rui Zheng 《Journal of Electronic Research and Application》 2023年第4期1-6,共6页
In order to improve the performance and reliability of the radio and televisio transmission system and prowide users with a better audiovisual experience,this paper first analyzes the advantages of microwave in radio ... In order to improve the performance and reliability of the radio and televisio transmission system and prowide users with a better audiovisual experience,this paper first analyzes the advantages of microwave in radio and television transmitters,and further elaborates the radio and television transmission system.Through the reasonable configuration and appication of microwave equipment,the performance and reliability of radio and television transmission system can be improved,and the stable transmission of radio and television signals can be ensured. 展开更多
关键词 MICROWAVE Launch pad television broadeast
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Signal and Data Processing of Television Based on Multistatic Radar Systems 被引量:1
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作者 李硕 曾涛 龙腾 《Journal of Beijing Institute of Technology》 EI CAS 2002年第3期271-275,共5页
A television based multistatic radar system is described. The commercial television transmitter is used as the illuminator in the multistatic radar system. The reflected commercial television signals are measured by ... A television based multistatic radar system is described. The commercial television transmitter is used as the illuminator in the multistatic radar system. The reflected commercial television signals are measured by an array of sensors. A data processing scheme is developed that adapts to the poor signal processing ability. The innovation is focused on the construction of the observation space, which could reduce the non linearity error. The new method leads to better system stability than the traditional one. Monte Carlo simulation is utilized and compared with the traditional method. 展开更多
关键词 multistatic radar television signal signal detection tracking and filter sequential processing
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Effect of Television Viewing on Pediatric Obesity 被引量:5
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作者 MAGUAN-SHENG LIYAN-PING 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2002年第4期291-297,共7页
Objective To test the effect of television viewing on pediatric obesity in urban China. Methods Stratified multistage cluster random sampling method was used for subjects selection. Nine thousand three hundred and fif... Objective To test the effect of television viewing on pediatric obesity in urban China. Methods Stratified multistage cluster random sampling method was used for subjects selection. Nine thousand three hundred and fifty-six children, as well as their parents, were investigated. Questionnaire survey was used for data collection. Children's weights and heights were measured in the clinic of the investigated kindergartens or schools by trained investigators following the standardized procedure. Results The percentages of children and adolescents who watched television less than 1 h, 1-2 h, 2-3 h and more than 3 h daily were 32.5%, 46.0%, 15.4% and 6.1%, respectively, while the prevalence of obesity was 10.9%, 11.8%, 13.2% and 15.1%, respectively. Each hourly increment of television viewing was associated with 1 %-2% increase in the prevalence of obesity. Conclusions Time spent watching television is directly related to an increase risk of obesity, television viewing time is an independent factor for pediatric obesity. 展开更多
关键词 Children and adolescent television viewing OBESITY
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Television News Coverage of Obesity in China,1982-2009 被引量:3
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作者 YI Zhe XU Rui Qing +1 位作者 ZHAO Kun LIKe Ji 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2012年第3期325-333,共9页
Objective The purpose of this study was to explore how obesity was covered in television news in China, including the trends over time and the characteristics of obesity-related news. Methods The frame analysis was ad... Objective The purpose of this study was to explore how obesity was covered in television news in China, including the trends over time and the characteristics of obesity-related news. Methods The frame analysis was adopted to assess the content of obesity-related news broadcasted in China Central Television (CCTV) from 1982 to 2009. To investigate the characteristics of the news, the obesity-related news was divided into subgroups according to populations concerned, as well as the period in which the news was broadcasted. The differences between subgroups were examined. Results A total of 1 599 pieces of news reported obesity, in which 1 278 pieces (79.92%) aired in "wealthy" period (2006-2009). More news was concerned with adults (1 134, 70.92%). "Individual behavior" dominated most of the cause frames (389, 24.33%), solution frames (522, 32.65%), and responsibility frames (860, 53.78%). There was more news mentioning individual factors in news aired in "wealthy" period and news concerning children. The coverage of social-structure causes was higher in news concerning children, while the coverage of social-structure solutions was higher in news concerning children and news aired in "wealthy" period. Conclusion Although the coverage of obesity was modest, it showed an incremental trend as the economy grew. Obesity was mostly depicted as an individual problem in terms of responsibility, causes and solutions. 展开更多
关键词 OBESITY television NEWS Frame analysis
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High-definition colonoscopy with i-Scan:Better diagnosis for small polyps and flat adenomas 被引量:12
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作者 Pier Alberto Testoni Chiara Notaristefano +2 位作者 Cristian Vailati Milena Di Leo Edi Viale 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第37期5231-5239,共9页
AIM: To investigate if high-definition (HD) colonoscope with i-Scan gave a higher detection rate of mucosal le- sions vs standard white-light instruments. METHODS: Data were collected from the computer- ized datab... AIM: To investigate if high-definition (HD) colonoscope with i-Scan gave a higher detection rate of mucosal le- sions vs standard white-light instruments. METHODS: Data were collected from the computer- ized database of the endoscopy unit of our tertiary referral center. We retrospectively analyzed 1101 con- secutive colonoscopies that were performed over 1 year with standard white-light (n = 849) or HD+ with i-Scan (n = 252) instruments by four endoscopists, in an outpatient setting. Colonoscopy records included patients' main details and family history for colorectal cancer, indication for colonoscopy (screening, diagnos- tic or surveillance), type of instrument used (standard white-light or HD+ plus i-Scan), name of endoscopist and bowel preparation. Records for each procedure included whether the cecum was reached or not and the reason for failure, complications during or imme- diately after the procedure, and number, size, location and characteristics of the lesions. Polyps or protruding lesions were defined as sessile or pedunculated, and nonprotruding lesions were defined according to Paris classification. For each lesion, histological diagnosis was recorded. RESULTS: Eight hundred and forty-nine colonosco- pies were carried with the standard white-light video colonoscope and 252 with the HD+ plus i-Scan video colonoscope, The four endoscopists did 264, 300, 276 and 261 procedures, respectively; 21.6%, 24.0%, 21.7% and 24.1% of them with the HD+ plus i-Scan technique. There were no significant differences be- tween the four endoscopists in either the number of procedures done or the proportions of each imaging technique used. Both techniques detected one or more mucosal lesions in 522/1101 procedures (47.4%). The overall number of lesions recognized was 1266; 645 in the right colon and 621 in the left. A significantly higher number of colonoscopies recognized lesions in the HD+ plus i-Scan mode (171/252 = 67.9%) than with the standard white-light technique (408/849 = 48.1%) (P 〈 0.0001). HD+ with i-Scan colonoscopies identified more lesions than standard white-light imag- ing (459/252 and 807/849, P 〈 0.0001), in the right or left colon (mean :1: SD, 1.62±1.36 vs 1.33±0.73, P 〈 0.003 and 1.55±0.98 vs 1.17±0.93, P = 0.033), more lesions 〈 10 mm (P 〈 0.0001) or nonprotruding (P 〈 0.022), and flat polyps (P = 0.04). The cumulative mean number of lesions per procedure detected by the four endoscopists was significantly higher with HD+ with i-Scan than with standard white-light imaging (1.82 ± 2.89 vs 0.95± 1.35, P 〈 0.0001). CONCLUSION: HD imaging with i-Scan during the withdrawal phase of colonoscopy significantly increased the detection of colonic mucosal lesions, particularly small and nonprotruding polyps. 展开更多
关键词 COLONOSCOPY high-definition with i-Scancolonoscopy White-light colonoscopy Colonic polyps Nonprotruding lesions Adenoma detection rate With-drawal time Surface enhancement Contrast enhance-ment Tone enhancement
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Online Data Processing Methods in Xlet Applications for Seismic Early Warning and Emergency Services on Interactive Digital Television 被引量:1
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作者 Mustafa Asim Kazancigil 《International Journal of Communications, Network and System Sciences》 2013年第5期221-235,共15页
In this paper, I described the methods that I used for the creation of Xlets, which are Java applets that are developed for the IDTV environment;and the methods for online data retrieval and processing that I utilized... In this paper, I described the methods that I used for the creation of Xlets, which are Java applets that are developed for the IDTV environment;and the methods for online data retrieval and processing that I utilized in these Xlets. The themes that I chose for the Xlets of the IDTV applications are Earthquake and Tsunami Early Warning;Recent Seismic Activity Report;and Emergency Services. The online data regarding the Recent Seismic Activity Report application are provided by the Kandilli Observatory and Earthquake Research Institute (KOERI) of Bogazici University in Istanbul;while the online data for the Earthquake and Tsunami Early Warning and the Emergency Services applications are provided by the Godoro website which I used for storing (and retrieving by the Xlets) the earthquake and tsunami early warning simulation data, and the DVB network subscriber data (such as name and address information) for utilizing in the Emergency Services (Police, Ambulance and Fire Department) application. I have focused on the methodologies to use digital television as an efficient medium to convey timely and useful information regarding seismic warning data to the public, which forms the main research topic of this paper. 展开更多
关键词 Xlet Java TV INTERACTIVE Digital television DVB Data Processing SEISMIC Early WARNING
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Discussion on the Problems Faced by Film and Television Education and the Development Trends in the New Media Environment 被引量:1
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作者 Jianliang Gu 《Review of Educational Theory》 2019年第4期42-45,共4页
With the development of the economy,film and television education has gradually received more and more attention.With the rapid development of new media technologies,there are still some problems in film and televisio... With the development of the economy,film and television education has gradually received more and more attention.With the rapid development of new media technologies,there are still some problems in film and television education in the new media environment.This paper mainly analyzes the problems faced by film and television education in the new media environment,and the development direction of film and television education in the new media era,and explores the forms of film and television education and film industry integration. 展开更多
关键词 Film and television EDUCATION New media environment Development TRENDS
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Teaching Television-A Review of John Hartley's Uses of Television
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作者 陈芃 《海外英语》 2011年第8X期397-398,共2页
This is to review and analyse the chapters of one of John Hartley's works Uses of Television, and compare it with different readers related to the studies of TV. It mainly discusses teaching television in four par... This is to review and analyse the chapters of one of John Hartley's works Uses of Television, and compare it with different readers related to the studies of TV. It mainly discusses teaching television in four parts: the effect of the audience on television, textual tradition and television, television and citizenship, and television as transmodern teaching. 展开更多
关键词 television TEACHING EFFECT
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Research and Application of Broad-Storage Architecture in Digital Television System
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作者 邢玲 马建国 +1 位作者 李幼平 刘志文 《Journal of Beijing Institute of Technology》 EI CAS 2009年第2期215-219,共5页
A new dual-mode transmission networks (DMTN) based on broad-storage architecture for digital television (DTV) is proposed, in which the primary TV network is superimposed by a complementary framework based on broa... A new dual-mode transmission networks (DMTN) based on broad-storage architecture for digital television (DTV) is proposed, in which the primary TV network is superimposed by a complementary framework based on broad-storage TV (BSTV). The necessity of congregating hot TV resources is discussed via analyzing the scale-free properties in DMTN. The self-organized parallel broadcasting technology (SPBT) and the uniform content locator (UCL) are studied to utilize availably transmission channels and to help consumers to communicate with each other expediently. Experimental results show that DMTN can provide not only traditional TV services on schedule, but also digital interactive TV services on demand by using a single channel. 展开更多
关键词 interactive television digital television (DTV) uniform content loeator (UCL) scale-free properties
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Association of Television Watching Practices of Mothers on Overweight and Obesity of Their Under-5 Offspring in Urban Bangladesh
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作者 Jui Das Sumon Kumar Das +8 位作者 Shahnawaz Ahmed Mohammod Jobayer Chisti Mohammad Habibur Rahman Sarker Fahmida Dil Farzana Farzana Ferdous Mohammad Abdul Malek Aminur Rahman Abu Syed Golam Faruque Abdullah Al Mamun 《Food and Nutrition Sciences》 2014年第19期1811-1817,共7页
Childhood overweight and obesity, is an emerging public health concern in developing countries like Bangladesh. However, regular television watching by child’s mother and its impact on excess weight gain or overweigh... Childhood overweight and obesity, is an emerging public health concern in developing countries like Bangladesh. However, regular television watching by child’s mother and its impact on excess weight gain or overweight and obesity to their offspring is not reported elsewhere. The aim of the present analysis was to determine the socio-demographic characteristics among overweight and obese children based on those mothers who watch television regularly and compare this finding with malnourished and well-nourished under-5 children. A total of 20,800 under-5 children were enrolled during 1996 to 2012 in the Diarrheal Disease Surveillance System (DDSS) of Dhaka Hospital of International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b). Mean weight-for-age z-score (–1.61 vs. –2.30;mean difference: ?0.69;p < 0.001), height-for-age z-score (–1.42 vs. –1.99;–0.57;<0.001), weight-for-height z-score (–1.59 vs. –1.07;–0.53;<0.001), BMI-for-age z-score (–1.09 vs. –1.61, –0.52;<0.001) differed significantly between the children whose mother did and did not watch television regularly. Under-5 children whose mother watched television regularly (2%) compared to those who did not (1%), had 2.28 [(95% CI-1.61 - 3.24) p < 0.001] times increased odds of being overweight and obese. Television watching of mothers is associated with childhood overweight and obesity and is one of the most public health concerns in Bangladesh. These changes may be in part of better socio-economic condition, changes in life style behaviour and dietary pattern. 展开更多
关键词 Childhood OVERWEIGHT and Obesity Mother’s WATCHING of television URBAN BANGLADESH
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HIGH-EFFICIENCY CODING FOR PAL COLOR TELEVISION SIGNAL
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作者 程玉林 《Journal of Electronics(China)》 1994年第2期135-142,共8页
Proceeding from the specific characteristics of PAL television signals adopted in China this paper points out that if the fs = 2fsc of sub-Nyquist sampling and DPCM encoding is used for PAL complete signal and if the ... Proceeding from the specific characteristics of PAL television signals adopted in China this paper points out that if the fs = 2fsc of sub-Nyquist sampling and DPCM encoding is used for PAL complete signal and if the blanking time is utilized to transmit code of effective area, it is possible to transmit a color TV signal over PCM three-group channel. 展开更多
关键词 Digital television High-efficiency CODING Sub-Nyquist sampling DIFFERENTIAL PULSE code modulation Effective area CODING
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Optical diagnosis of colorectal polyps using high-definition i-scan: An educational experience
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作者 Mariёlle WE Bouwens Rogier de Ridder +4 位作者 Ad AM Masclee Ann Driessen Robert G Riedl Bjorn Winkens Silvia Sanduleanu 《World Journal of Gastroenterology》 SCIE CAS 2013年第27期4334-4343,共10页
AIM:To examine performances regarding prediction of polyp histology using high-definition (HD) i-scan in a group of endoscopists with varying levels of experience. METHODS:We used a digital library of HD i-scan still ... AIM:To examine performances regarding prediction of polyp histology using high-definition (HD) i-scan in a group of endoscopists with varying levels of experience. METHODS:We used a digital library of HD i-scan still images, comprising twin pictures (surface enhancement and tone enhancement), collected at our university hospital. We defined endoscopic features of adenomatous and non-adenomatous polyps, according to the following parameters:color, surface pattern and vascular pattern. We familiarized the participating endoscopists on optical diagnosis of colorectal polyps using a 20-min didactic training session. All endoscopists were asked to evaluate an image set of 50 colorectal polyps with regard to polyp histology. We classified the diagnoses into high confidence (i.e., cases in which the endoscopist could assign a diagnosis with certainty) and low confidence diagnoses (i.e., cases in which the endoscopist preferred to send the polyp for formal histology). Mean sensitivity, specificity and accuracy per endoscopist/image were computed and differences between groups tested using independent-samples t tests. High vs low confidence diagnoses were compared using the pairedsamples t test. RESULTS:Eleven endoscopists without previous experience on optical diagnosis evaluated a total of 550 images (396 adenomatous, 154 non-adenomatous). Mean sensitivity, specificity and accuracy for diagnosing adenomas were 79.3%, 85.7% and 81.1%, respectively. No significant differences were found between gastroenterologists and trainees regarding performances of optical diagnosis (mean accuracy 78.0%vs 82.9%,P = 0.098). Diminutive lesions were predicted with a lower mean accuracy as compared to non-diminutive lesions (74.2% vs 93.1%, P = 0.008). A total of 446 (81.1%) diagnoses were made with high confidence. High confidence diagnoses corresponded to a significantly higher mean accuracy than low confidence diagnoses (84.0% vs 64.3%, P = 0.008). A total of 319 (58.0%) images were evaluated as having excellent quality. Considering excellent quality images in conjunction with high confidence diagnosis, overall accuracy increased to 92.8%. CONCLUSION:After a single training session, endoscopists with varying levels of experience can already provide optical diagnosis with an accuracy of 84.0%. 展开更多
关键词 COLONOSCOPY high-definition i-scan Optical diagnosis Colorectal POLYPS Training
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Low Noise Amplifier Design for Digital Television Applications
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作者 Anastasios Tsaraklimanis Evangelia Karagianni 《Journal of Electromagnetic Analysis and Applications》 2011年第7期291-296,共6页
The DVB-T (Digital Video Broadcasting—Terrestrial) standard is being deployed in many parts of the world for digital broadcasting services, providing a variety of features extending the capabilities of the older anal... The DVB-T (Digital Video Broadcasting—Terrestrial) standard is being deployed in many parts of the world for digital broadcasting services, providing a variety of features extending the capabilities of the older analog ones. In this paper, a two-stage low noise amplifier (LNA) is designed for use with the DVB-T standard. The design is employed based on microstrip. The microwave design meets all the specifications required, achieving input and output return loss below ?10 dB, high gain of 35 dB and high linearity. Low noise figure of 1.3 dB is achieved with the use of pHEMT transistor technology. 展开更多
关键词 Digital television Low Noise AMPLIFIERS MICROWAVE CIRCUITS
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Improvement Strategies of Meteorological Movie and Television Services Facing Public Needs
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作者 Xiaoli Wang Bichun Li 《Meteorological and Environmental Research》 CAS 2013年第8期10-13,共4页
The development course of China's meteorological movie and television was analyzed firstly, and then the improvement strategies of meteorological movie and television services facing public needs were put forward bas... The development course of China's meteorological movie and television was analyzed firstly, and then the improvement strategies of meteorological movie and television services facing public needs were put forward based on the statistical results of a meteorological service questionnaire. 展开更多
关键词 Public needs Meteorological movie and television services Improvement strategies China
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Delivery Digital Television Services over Ethernet
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作者 左健存 孙秋冬 黄晓东 《Journal of Donghua University(English Edition)》 EI CAS 2011年第3期321-325,共5页
A new architecture for digital television (DTV) delivery based on Ethernet was presented. In this architecture, new protocol stack and packet encapsulation were proposed to help implementation of DTV services over Eth... A new architecture for digital television (DTV) delivery based on Ethernet was presented. In this architecture, new protocol stack and packet encapsulation were proposed to help implementation of DTV services over Ethernet link. A simple quality of service (QoS) structure was provided in traffic control of nodes to achieve QoS requirements of DTV delivery. Experiments were proceeded successfully to implement the idea. Finally, a short evaluation to QoS provisions was given, achieving good results. 展开更多
关键词 digital television (DTV) ETHERNET quality of service (QoS)
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Empirical Studies on Topographical Influences on Crbc/Akbc Terrestrial Television Stations’ Signals in Akpabuyo Local Council Area, Nigeria
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作者 Donatus Enang Bassey Godwin O. Effiong +1 位作者 Ofem U. Omini Effiong O. Obisung 《Journal of Computer and Communications》 2019年第9期50-71,共22页
Dissemination of information to citizens is a relevant component of governance. Expectedly, viewers tuned to broadcast stations within and outside their localities, expecting their receivers to faithfully reproduce th... Dissemination of information to citizens is a relevant component of governance. Expectedly, viewers tuned to broadcast stations within and outside their localities, expecting their receivers to faithfully reproduce the exact features of the transmitted signal. Akpabuyo is a dense forest zone near the creeks leading to the Atlantic ocean in Cross River State, Nigeria. The location has distinct environmental characteristics that made Akpabuyo Area Council, a challenging location to propagate electromagnetic waves;and therefore recipe for further investigation. Radio frequency analyzer, with 24 channels spectrum, ranging between 46 - 870 MHz (model: RO.VE.R.-“DLM3-T”) was deployed to capture signals from terrestrial television stations (TV). CATV measured signal of TV stations in dB, dBμV and dBmV. Its frequency ranged from 40 - 860 MHz;while varying from channel 1 to channel 69. Measurements taken from Akpabuyo L.G.A. showed the following results: the signal strength received from VHF Channel 11 ranged from 20 dBμV to 49 dBμV. From recorded empirical statistics from the study, 50% of the area received signal from this station above 30 dBμV, while other regions had signals below this value;representing the fringe zone of the frequency. The results obtained from the study relatively showed acceptance with Egli’s model. The study recorded a steady fluctuation between 17 dBμV and 19 dBμV from both propagating stations. However, Channel 27 signal at 519 MHz, had very weak signal coverage in Akpabuyo Local Government Area;with signal strength dropped to as low as 13 dB in many parts of the rural area. The study discovered that the state’s broadcasting stations, both at UHF and VHF channels did not transmit successfully across this densely forest (rural) location. Remedial measures such as installing Repeater stations at different locations as signal booster were recommended. 展开更多
关键词 Akamkpa Biase BROADCAST Station Channels Propagation Models Signal television STATIONS UHF/VHF SIGNALS
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Birth of"Television Set" in Tashkent
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作者 Yuldashev Eldar Sadikovich 《Journal of Literature and Art Studies》 2014年第8期661-668,共8页
The invention and development of television art is closely connected with scientific research. The historic facts have witnessed the influence of scientific research progress on the development of television art. In t... The invention and development of television art is closely connected with scientific research. The historic facts have witnessed the influence of scientific research progress on the development of television art. In this paper, the author intends to reveal some phenomenal facts which are known by very few people, namely, the first ever appearance of electronic television in Uzbekistan. This paper gives us some authentic and valuable historic materials for the invention and development of television set in the world. 展开更多
关键词 television electronic television television system
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