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Effects of body mass index on intraocular pressure and ocular pulse amplitude 被引量:3
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作者 Remzi Karadag Zeynel Arslanyilmaz +1 位作者 Bahri Aydin Ibrahim F. Hepsen 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2012年第5期605-608,共4页
AIM: To investigate the effects of body mass index (BMI) on intraocular pressure (IOP) and ocular pulse amplitude(OPA). METHODS: Totally 140 healthy individuals without any systemic diseases were included in the study... AIM: To investigate the effects of body mass index (BMI) on intraocular pressure (IOP) and ocular pulse amplitude(OPA). METHODS: Totally 140 healthy individuals without any systemic diseases were included in the study. BMI (kg/m2) was calculated for every individual. IOP and OPA were measured with Pascal Dynamic contour tonometer (DCT). Blood pressure was also measured along with the DCT. The patients were divided into three groups according to BMI as: Group1, BMI<25; Group2, 25≤BMI<30; Group3, BMI≥30. Mean values of IOP, OPA, systolic blood pressure (SBP) and diastolic blood pressure (DBP) were used in statistical analysis.RESULTS: In Group1, the means of IOP, OPA, were 16.8±2.3mmHg, 2.7±0.7mmHg respectively; and SBP, DBP were 120.0±6.1mmHg, and 77.4±5.6mmHg respectively. In group2, the mean IOP, OPA, SBP, and DBP were found to be 16.6±2.1mmHg, 2.4±0.7mmHg, 121.7±5.3mmHg, and 79.5±4.9mmHg respectively. In group3, the mean IOP, OPA, SBP, and DBP were found to be 17.3±1.7mmHg, 2.1±0.7mmHg, 122.4±5.7mmHg, and 79.7±5.2mmHg respectively. There were no statistically significant difference between groups in terms of IOP, SBP and DBP, while OPA values were significantly lower in group3 (P=0.001). CONCLUSION: Decreased OPA values in individuals with higher BMI may indicate that subjects with higher BMI have lower choroidal perfusion and lower ocular blood flow. 展开更多
关键词 body mass index choroidal perfusion intraocular pressure ocular pulse amplitude OBESITY
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Deinterleaving of radar pulse based on implicit feature
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作者 GUO Qiang TENG Long +2 位作者 WU Xinliang QI Liangang SONG Wenming 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2023年第6期1537-1549,共13页
In the complex countermeasure environment,the pulse description words(PDWs)of the same type of multi-function radar emitters are similar in multiple dimensions.Therefore,it is difficult for conventional methods to dei... In the complex countermeasure environment,the pulse description words(PDWs)of the same type of multi-function radar emitters are similar in multiple dimensions.Therefore,it is difficult for conventional methods to deinterleave such emitters.In order to solve this problem,a pulse deinterleaving method based on implicit features is proposed in this paper.The proposed method introduces long short-term memory(LSTM)neural networks and statistical analysis to mine new features from similar PDW features,that is,the variation law(implicit features)of pulse sequences of different radiation sources over time.The multi-function radar emitter is deinterleaved based on the pulse sequence variation law.Statistical results show that the proposed method not only achieves satisfactory performance,but also has good robustness. 展开更多
关键词 multi-functional radars of the same type pulse deinterleaving pulse amplitude implicit feature long short-term memory(LSTM)neural networks.
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Temperature and light tolerance of representative brown,green and red algae in tumble culture revealed by chlorophyll fluorescence measurements 被引量:4
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作者 PANG Shaojun SHAN Tifeng 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2008年第4期137-146,共10页
Laminaria japonica, Undaria pinnatifida, Ulva lactuca, Grateloupia turuturu and Palmaria palmata are suitable species that fit the requirements of a seaweed-animal integrated aquaculture system in terms of their viabl... Laminaria japonica, Undaria pinnatifida, Ulva lactuca, Grateloupia turuturu and Palmaria palmata are suitable species that fit the requirements of a seaweed-animal integrated aquaculture system in terms of their viable biomass, rapid growth and promising nutrient uptake rates. In this investigation, the responses of the optimal chlorophyll fluorescence yield of the five algal species in tumble culture were assessed at a temperature range of 10 - 30℃. The results revealed that Ulva lactuca was the most resistant species to high temperature, withstanding 30℃ for 4 h without apparent decline in the optimal chlorophyll fluorescence yield . While the arctic alga Palmaria palmata was the most vulnerable one, showing significant decline in the optimal chlorophyll fluorescence yield at 25℃ for 2 h. The cold-water species Laminaria japonica, however, demonstrated strong ability to cope with higher temperature (24 -26℃ ) for shorter time (within 24 h) without significant decline in the optimal chlorophyll fluorescence yield . Grateloupia turuturu showed a general decrease in the optimal chlorophyll fluorescence yield with the rising temperature from 23 to 30℃ , similar to the temperate kelp Undaria pinnatifida. Changes of chlorophyll fluorescence yields of these algae were characterized differently indicating the existence of species-unique strategy to cope with high light. Measurements of the optimal chlorophyll fluorescence yield after short exposure to direct solar irradiance revealed how long these exposures could be without significant photoinhibition or with promising recovery in photosynthetic activities. Seasonal pattern of alternation of algal species in tank culture in the Northern Hemisphere at the latitude of 36°N was proposed according to these basic measurements. 展开更多
关键词 seaweeds chlorophyll fluorescence measurements pulse amplitude Modulation temperature tolerance integrated aquaculture
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TEMPLATE MATCHING ALGORITHM OF RADAR BEAM SCAN TYPE RECOGNITION 被引量:3
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作者 Liang Huadong Han Jianghong Guo Guohua 《Journal of Electronics(China)》 2014年第2期100-106,共7页
Phased array radar has been applied broadly because of its sound performance.But signal of phased array radar is of a wide variety of types.Therefore,recognition of phased array radar is the most puzzling aspect of th... Phased array radar has been applied broadly because of its sound performance.But signal of phased array radar is of a wide variety of types.Therefore,recognition of phased array radar is the most puzzling aspect of the whole emitter identification domain.To solve the problem,the article proposes the method that identifies phased array radar by pulse amplitude information,and studies the phased array radar,models transmit signal of them,and receiving signal by radar countermeasure reconnaissance receiver.From constructing template of pulse train's amplitude vector of mechanical scanning radar,computing distance of samples and standard template,finding threshold of the template matching arithmetic,the article puts forward the template matching algorithm of radar beam scan type recognition to identify phased array radar automatically. 展开更多
关键词 Beam scan RECOGNITION Template matching pulse amplitude Normative correlation coefficient
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All-Optical Wavelength Conversion with Amplitude Equalization and Pulse Shaping
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作者 C.W.Chow C.S.Wong H.K.Tsang 《光学学报》 EI CAS CSCD 北大核心 2003年第S1期491-492,共2页
A dual-wavelength-injection-locked (DWIL) Fabry-Perot (FP) laser is used as an all-optical wavelength converter and regenerator. Regenerated pulses have narrower pulse-width of 37ps. Power penalty and extinction-ratio... A dual-wavelength-injection-locked (DWIL) Fabry-Perot (FP) laser is used as an all-optical wavelength converter and regenerator. Regenerated pulses have narrower pulse-width of 37ps. Power penalty and extinction-ratio improvement of 1.5dB and 4dB respectively were achieved. 展开更多
关键词 EDFA on in as of MODE FP All-Optical Wavelength Conversion with amplitude Equalization and pulse Shaping with DBM
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Security enhanced underwater visible light communication system based on chaotic phase scrambling and conjugate frequency hopping
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作者 卢芝蓝 沈超 +1 位作者 施剑阳 迟楠 《Chinese Optics Letters》 SCIE EI CAS CSCD 2023年第6期11-16,共6页
We propose an encryption technique for underwater visible light communication[UVLC]based on chaotic phase scrambling[PS]and conjugate frequency hopping[CFH].The technique is experimentally tested using an 8-level puls... We propose an encryption technique for underwater visible light communication[UVLC]based on chaotic phase scrambling[PS]and conjugate frequency hopping[CFH].The technique is experimentally tested using an 8-level pulse amplitude modulation[PAM-8]and a 1.2 m underwater link.The security key of the phase scrambling code is generated according to a logistic map,and the frequency hopping is achieved by adding the same zero frequency points to the signal spectrum.The maximum transmission rate of 2.1 Gbit/s is measured with bit-error-rate[BER]below 7%the hard-decision forward error correction[HD-FEC]threshold of 3.8×10^(-3). 展开更多
关键词 underwater visible light communication pulse amplitude modulation phase scrambling logistic mapping conjugate frequency hopping
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Multi-distributed probabilistically shaped PAM-4 system for intra-data-center networks 被引量:1
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作者 刘梦丽 高明义 柯俊驰 《Chinese Optics Letters》 SCIE EI CAS CSCD 2021年第11期32-37,共6页
Probabilistically shaped(PS) pulse amplitude modulation(PAM) is a promising technique for intra-data-center networks due to its superior performance, for which a low-complexity and cost-effective distributed matching ... Probabilistically shaped(PS) pulse amplitude modulation(PAM) is a promising technique for intra-data-center networks due to its superior performance, for which a low-complexity and cost-effective distributed matching method is critical. In this work, we propose an energy-level-assigned method to yield PS-PAM-4 signals with various bit rates based on variable probabilistic distributions. We experimentally demonstrate the proposed method in a 25 Gbaud PS-PAM-4 transmission over a bandwidth of approximately 10 GHz. Compared to a uniform PAM-4 system, the proposed multi-distributed PS-PAM-4 system approaches the hard decision threshold at a wide range of received optical power for different applications. 展开更多
关键词 probabilistic shaping pulse amplitude modulation feed-forward equalizer
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A PO-CI/MC-CDMA scheme for high modulation styles
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作者 Yanyan ZHANG Lisha TANG +2 位作者 Xiaofeng TAO Xiaoxuan ZHU Ping ZHANG 《Frontiers of Electrical and Electronic Engineering in China》 CSCD 2008年第2期145-149,共5页
Through analyzing the theoretical spreading principle,it has been proved in this paper that the benefit of pseudo-orthogonal carrier interferometry(PO-CI)spreading code is not supported when complex signal modulation(... Through analyzing the theoretical spreading principle,it has been proved in this paper that the benefit of pseudo-orthogonal carrier interferometry(PO-CI)spreading code is not supported when complex signal modulation(e.g.,quadrature phase-shift keying(QPSK)and quadrature amplitude modulation(QAM))types are employed.On this basis,a novel and feasible structure for this problem is brought forward.Within the structure mentioned,instead of complex modulation patterns,pulse amplitude modulation(PAM)combined with PO-CI spreading code is utilized.This allows us to maintain the throughput increase of a multi-carrier code division multiple access(MC-CDMA)system with minimal loss in performance and no bandwidth expansion. 展开更多
关键词 pseudo-orthogonal carrier interferometry pulse amplitude modulation spreading/de-spreading multi-carrier code division multiple access doubled throughput
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