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An iterative approach to an integrated land use and transportation planning tool for small urban areas 被引量:1
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作者 Meiwu AN Mei CHEN 《Journal of Modern Transportation》 2012年第3期160-167,共8页
There has been increasing interests in developing land use models for small urban areas for various planning applications such as air quality conformity analysis. The output of a land use model can serve as a major in... There has been increasing interests in developing land use models for small urban areas for various planning applications such as air quality conformity analysis. The output of a land use model can serve as a major input to a transportation model; conversely, transportation model output can provide a critical input to a land use model. The connection between the two models can be achieved by an accessibility measure. This paper presents an iterative approach to solving a regression-based land use model and a transportation model with combined trip distribution- assignment. A case study using data from a small urban area is presented to illustrate the application of the proposed modeling framework. Tests show that the procedures can converge, and the modeling framework can be a valuable tool for planners and decision-makers in evaluating land use policies and transportation investment strategies. 展开更多
关键词 integrated land use and transportation model urban model travel demand model combined trip distribution and assignment model urban planning
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Integrated management strategy for improving the grain yield and nitrogen-use efficiency of winter wheat 被引量:5
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作者 XU Hai-cheng DAI Xing-long +5 位作者 CHU Jin-peng WANG Yue-chao YIN Li-jun MA Xin DONG Shu-xin HE Ming-rong 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2018年第2期315-327,共13页
Understanding of how combinations of agronomic options can be used to improve the grain yield and nitrogen use efficiency(NUE) of winter wheat is limited. A three-year experiment involving four integrated management... Understanding of how combinations of agronomic options can be used to improve the grain yield and nitrogen use efficiency(NUE) of winter wheat is limited. A three-year experiment involving four integrated management strategies was conducted from 2013 to 2015 in Tai'an, Shandong Province, China, to evaluate changes in grain yield and NUE. The integrated management treatments were as follows: current practice(T1); improvement of current practice(T2); high-yield management(T3), which aimed to maximize grain yield regardless of the cost of resource inputs; and integrated soil and crop system management(T4) with a higher seeding rate, delayed sowing date, and optimized nutrient management. Seeding rates increased by 75 seeds m^-2 with each treatment from T1(225 seeds m^-2) to T4(450 seeds m^-2). The sowing dates were delayed from T1(5 th Oct.) to T2 and T3(8 th Oct.), and to T4 treatment(12 th Oct.). T1, T2, T3, and T4 received 315, 210, 315, and 240 kg N ha^-1, 120, 90, 210 and 120 kg P2O5 ha^-1, 30, 75, 90, and 45 kg K2O ha^-1, respectively. The ratio of basal application to topdressing for T1, T2, T3, and T4 was 6:4, 5:5, 4:6, and 4:6, respectively, with the N topdressing applied at regreening for T1 and at jointing stage for T2, T3, and T4. The P fertilizers in all treatments were applied as basal fertilizer. The K fertilizer for T1 and T2 was applied as basal fertilizer while the ratio of basal application to topdressing(at jointing stage) of K fertilizer for both T3 and T4 was 6:4. T1, T2, T3, and T4 were irrigated five, four, four and three times, respectively. Treatment T3 produced the highest grain yield among all treatments over three years and the average yield was 9 277.96 kg ha^-1. Grain yield averaged across three years with the T4 treatment(8 892.93 kg ha^-1) was 95.85% of that with T3 and was 21.72 and 6.10% higher than that with T1(7 305.95 kg ha^-1) and T2(8 381.41 kg ha^-1), respectively. Treatment T2 produced the highest NUE of all the integrated treatments. The NUE with T4 was 95.36% of that with T2 and was 51.91 and 25.62% higher than that with T1 and T3, respectively. The N uptake efficiency(UPE) averaged across three years with T4 was 50.75 and 16.62% higher than that with T1and T3, respectively. The N utilization efficiency(UTE) averaged across three years with T4 was 7.74% higher than that with T3. The increased UPE with T4 compared with T3 could be attributed mostly to the lower available N in T4, while the increased UTE with T4 was mainly due to the highest N harvest index and low grain N concentration, which consequently led to improved NUE. The net profit for T4 was the highest among four treatments and was 174.94, 22.27, and 28.10% higher than that for T1, T2, and T3, respectively. Therefore, the T4 treatment should be a recommendable management strategy to obtain high grain yield, high NUE, and high economic benefits in the target region, although further improvements of NUE are required. 展开更多
关键词 integrated management strategy grain yield winter wheat nitrogen use efficiency nitrogen uptake efficiency nitrogen utilization efficiency
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INTEGRATED CONTROL FOR VEHICLE YAW MOTION USING DOUBLE-COST-FUNCTION LQR 被引量:5
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《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2000年第3期228-233,共7页
关键词 In integrated CONTROL FOR VEHICLE YAW MOTION USING DOUBLE-COST-FUNCTION LQR
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Land Use Changes in Himalaya and Their Impacts on Environment, Society and Economy: A Study of the Lake Region in Kumaon Himalaya, India 被引量:1
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作者 Prakash TIWARI 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2008年第6期1029-1042,共14页
The traditional resource use structure in Himalaya has transformed considerably during the recent past, mainly owing to the growth of population and the resultant increased demand of natural resources in the region. T... The traditional resource use structure in Himalaya has transformed considerably during the recent past, mainly owing to the growth of population and the resultant increased demand of natural resources in the region. This transformation in resource use practices is particularly significant in the densely populated tracts of Himalaya. As a result, cultivated land, forests, pastures and rangelands have been deteriorated and depleted steadily and significantly leading to their conversion into degraded and non-productive lands. These rapid land use changes have not only disrupted the fragile ecological equilibrium in the mountains through indiscriminate deforestation, degradation of land resources and disruption of the hydrological cycle, but also have significant and irreversible adverse impacts on the rural economy, society, livelihood and life quality of mountain communities. It has been observed that the agricultural production has declined, water sources are drying up fast due to decreased ground water recharge and a large number of villages are facing enormous deficit of critical resources, such as food, fodder, firewood and water, mainly due to unabated deforestation. As a result, the rural people, particularly the women, have to travel considerably long distances to collect fodder and firewood and to fetching water. It is therefore highly imperative to evolve a comprehensive and integrated land use framework for the conservation of the biophysical environment and sustainable development of natural resources in Himalaya. The land use policy would help local communities in making use of their natural resources scientifically and judiciously, and thus help in the conservation of the biophysical environment and in the increasing of the productivity of natural resources. The study indicates that conservation of forests and other critical natural resources through community participation, generation of alternative means of livelihood, and employment in rural areas can help increase rural income as well as restore ecosystem services. 展开更多
关键词 subsistence agriculture population growth resource use pattern urbanization deforestation hydrological disruptions resource deficit integrated land use framework
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Chip-scale broadband spectroscopic chemical sensing using an integrated supercontinuum source in a chalcogenide glass waveguide 被引量:9
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作者 QINGYANG DU ZHENGQIAN LUO +6 位作者 HUIKAI ZHONG YIFEI ZHANG YIZHONG HUANG TUANJIE DU WEI ZHANG TIAN GU JUEJUN HU 《Photonics Research》 SCIE EI 2018年第6期506-510,共5页
On-chip spectroscopic sensors have attracted increasing attention for portable and field-deployable chemical detection applications. So far, these sensors largely rely on benchtop tunable lasers for spectroscopic inte... On-chip spectroscopic sensors have attracted increasing attention for portable and field-deployable chemical detection applications. So far, these sensors largely rely on benchtop tunable lasers for spectroscopic interrogation. Large footprint and mechanical fragility of the sources, however, preclude compact sensing system integration. In this paper, we address the challenge through demonstrating, for the first time to our knowledge, a supercontinuum source integrated on-chip spectroscopic sensor, where we leverage nonlinear Ge_(22)Sb_(18)Se_(60) chalcogenide glass waveguides as a unified platform for both broadband supercontinuum generation and chemical detection. A home-built, palm-sized femtosecond laser centering at 1560 nm wavelength was used as the pumping source. Sensing capability of the system was validated through quantifying the optical absorption of chloroform solutions at 1695 nm. This work represents an important step towards realizing a miniaturized spectroscopic sensing system based on photonic chips. 展开更多
关键词 Chip-scale broadband spectroscopic chemical sensing using an integrated supercontinuum source in a chalcogenide glass waveguide length SC
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Vertically Integrated Thermo-Optic Waveguide Switch Using Optical Polymers 被引量:2
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作者 Ki-Hong Kim Sang-Yung Shin Doo-Sun Choi 《光学学报》 EI CAS CSCD 北大核心 2003年第S1期359-360,共2页
We propose and fabricate a vertically integrated thermo-optic waveguide switch. It controls the optical path between two vertically stacked waveguides using the thermo-optic effect of optical polymer. The measured cro... We propose and fabricate a vertically integrated thermo-optic waveguide switch. It controls the optical path between two vertically stacked waveguides using the thermo-optic effect of optical polymer. The measured crosstalk is less than -10 dB. 展开更多
关键词 mode in HEAT it THAN Vertically integrated Thermo-Optic Waveguide Switch Using Optical Polymers of
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Research on photodiode integrated with wide spectrum focusing reflector using nonperiodic subwavelength gratings 被引量:2
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作者 刘涛 黄永清 +5 位作者 费嘉瑞 武刚 马晓凯 段晓峰 刘凯 任晓敏 《Chinese Optics Letters》 SCIE EI CAS CSCD 2018年第5期52-55,共4页
The fabrication and characterization of p-i-n photodiodes integrated with wide spectrum focusing reflectors using nonperiodic strip and concentric-circular subwavelength gratings are presented. The experimental result... The fabrication and characterization of p-i-n photodiodes integrated with wide spectrum focusing reflectors using nonperiodic strip and concentric-circular subwavelength gratings are presented. The experimental results show that the gratings can reflect and focus the incident light on the absorber of the photodiode, and thus can simultaneously achieve high speed and high efficiency. For the gratings’ integrated photodiodes, the responsivity is improved over a wide spectral range, and when the absorber was 600 nm and the mesa diameter was40 μm, a responsivity of 0.46 A/W at a wavelength of 1.55 μm and a 3 dB bandwidth of 21.6 GHz under a reverse bias of 3 V were simultaneously obtained. 展开更多
关键词 length Research on photodiode integrated with wide spectrum focusing reflector using nonperiodic subwavelength gratings
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Photonic microwave true time delays for phased array antennas using a 49 GHz FSR integrated optical micro-comb source[Invited] 被引量:5
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作者 XINGYUAN Xu JIAYANG Wu +6 位作者 THACH G.NGUYEN TANIA MOEIN SAI T.CHU BRENT E.LITTLE ROBERTO MORANDOTTI ARNAN MITCHELL DAVID J.Moss 《Photonics Research》 SCIE EI 2018年第5期I0055-I0061,共7页
We demonstrate significantly improved performance of a microwave true time delay line based on an integrated optical frequency comb source. The broadband micro-comb(over 100 nm wide) features a record low free spectra... We demonstrate significantly improved performance of a microwave true time delay line based on an integrated optical frequency comb source. The broadband micro-comb(over 100 nm wide) features a record low free spectral range(FSR) of 49 GHz, resulting in an unprecedented record high channel number(81 over the C band)—the highest number of channels for an integrated comb source used for microwave signal processing. We theoretically analyze the performance of a phased array antenna and show that this large channel count results in a high angular resolution and wide beam-steering tunable range. This demonstrates the feasibility of our approach as a competitive solution toward implementing integrated photonic true time delays in radar and communications systems. 展开更多
关键词 FSR Invited Photonic microwave true time delays for phased array antennas using a 49 GHz FSR integrated optical micro-comb source
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Multiwavelength generation using an add-drop microring resonator integrated with an InGaAsP/InP sampled grating distributed feedback 被引量:1
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作者 S.E.Alavi I.S.Amiri +3 位作者 M.R.K.Soltanian R.Penny A.S.M.Supa'at H.Ahmad 《Chinese Optics Letters》 SCIE EI CAS CSCD 2016年第2期27-32,共6页
A system of an add-drop microring resonator integrated with a sampled grating distributed feedback (SG-DFB) is investigated via modeling and simulation with the time-domain traveling wave (TDTW) method. The propos... A system of an add-drop microring resonator integrated with a sampled grating distributed feedback (SG-DFB) is investigated via modeling and simulation with the time-domain traveling wave (TDTW) method. The proposed microring resonator comprises a SiO2 waveguide integrated with an InGaAsP/InP SG-DFB, and the SiO2 waveguide consists of a silicon core having a refractive index of 3.48 and Kerr co- efficient of 4.5 × 10^-18 m2/W. The SG-DFB consists of a series of grating bursts that are constructed using a periodic apodization function with a burst spacing in the grating of 45 μm, a burst length of 5 μm, and I0 bursts across the total length of the SG-DBR. Transmission results of the through and drop port of the microring resonator show the significant capacity enhancement of the generated center wavelengths. The Q-factor of the microring resonator system, defined as the center wavelength (λ0) divided by 3 dB FWHM, without and with integration with the SG-DFB is calculated as 1.93 × 10^5 and 2.87 × 10^5, respectively. Analysis of the dispersion of the system reveals that increasing the wavelength results in a decrease of the dispersion. The higher capacity and efficiency are the advantages of integrating the microring resonator and the InGaAsP/InP SG-DFB. 展开更多
关键词 Ga As Multiwavelength generation using an add-drop microring resonator integrated with an InGaAsP/InP sampled grating distributed feedback DFB SG
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Knowledge, attitude and use of complementary and integrative health strategies: a preliminary survey of Iranian nurses 被引量:1
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作者 Abbas Balouchi Mozhgan Rahnama +2 位作者 Marie Hastings-Tolsma Mohammadali M.Shoja Enayatollah Bolaydehyi 《Journal of Integrative Medicine》 SCIE CAS CSCD 2016年第2期121-127,共7页
BACKGROUND: Disagreement exists regarding the need for knowledge about complementary and integrative health(CIH) strategies, as well as for the need to consider such strategies in clinical nursing practice. OBJECT... BACKGROUND: Disagreement exists regarding the need for knowledge about complementary and integrative health(CIH) strategies, as well as for the need to consider such strategies in clinical nursing practice. OBJECTIVE: This study was conducted to assess the knowledge, attitude and use of CIH strategies among nurses in Iran. DESIGN, SETTING, PARTICIPANTS AND INTERVENTIONS: A cross-sectional study of nurses working in two hospitals of Zabol University of Medical Sciences, in southeast Iran, was conducted from October 2014 to April 2015. The questionnaire, developed specifically for this research, was used to assess the knowledge, attitude and use of CIH by nurses. Descriptive and inferential statistics were used to interpret the survey responses.RESULTS: Most nurses(n=95, 60.5%) have average knowledge about CIH strategies with most holding a positive attitude about use(n=81, 51.6%). The majority(n=90, 57.3%) of nurses, however, never applied CIH methods. Where CIH was used, massage was most often clinically applied(n=129, 82.2%) and a large percentage believed it useful for treating illness(n=136, 87.9%). Other CIH methods commonly used included prayer and herbal medicine.CONCLUSION: Nurses have positive attitudes about CIH though knowledge was typically weak. Educational programs should carefully consider how knowledge about CIH methods could be strengthened within curricula. 展开更多
关键词 knowledge attitude and use nurses complementary and alternative medicine complementary and integrative health
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Urban Transport and Sustainable Transport Strategies: A Case Study of Karachi, Pakistan 被引量:1
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作者 Intikhab Ahmed Qureshi 陆化普 《Tsinghua Science and Technology》 EI CAS 2007年第3期309-317,共9页
The uncontrolled growth in urbanization and motorization generally contributes to an urban land use and transportation system that is socially, economically, and environmentally unsustainable. This paper uses Karachi ... The uncontrolled growth in urbanization and motorization generally contributes to an urban land use and transportation system that is socially, economically, and environmentally unsustainable. This paper uses Karachi as a case study, which is the largest urban and economic centre of Pakistan, passing through an uncontrolled phase of rapid urbanization and motorization. The paper first reviews research related to sustainable transportation systems to comprehend the concept of sustainable development and transportation. The paper then evaluates the existing transportation and infrastructure system, national transportation policies, and urban transportation projects to determine if the current paradigm is moving toward or away from sustainable transportation. Furthermore, the principles for sustainable urban transportation are developed to see what significance national transportation policies have given to urban transportation from a sustainable transportation point of view. Finally some strategies are suggested, adoption of which may lead to a sustainable urban development and transportation system in Karachi. 展开更多
关键词 sustainable development URBANIZATION MOTORIZATION SOCIO-ECONOMIC integrated land use and urban transportation system
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Strategies and Methods for the Treatment of Diabetic Neuropathy Using Integrative Chinese and Western Medicine 被引量:4
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作者 衡先培 《Chinese Journal of Integrative Medicine》 SCIE CAS 2008年第4期245-247,共3页
Diabetic neuropathy (DN) is the most common metabolic neuropathy in clinics, not only in diabetes patients (〉60%), but also in pre-diabetic (8%) and normal persons (5%)^(1). Its pathogenesis has not been fu... Diabetic neuropathy (DN) is the most common metabolic neuropathy in clinics, not only in diabetes patients (〉60%), but also in pre-diabetic (8%) and normal persons (5%)^(1). Its pathogenesis has not been fully understood up to now. It is generally believed that it is related to the increase in glycation endoproducts (AGEs) caused by hyperglycemia, 展开更多
关键词 Strategies and Methods for the Treatment of Diabetic Neuropathy Using Integrative Chinese and Western Medicine
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InP photonic circuits using generic integration [Invited] 被引量:1
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作者 K.A.Williams E.A.J.M.Bente +5 位作者 D.Heiss Y.Jiao K.Lawniczuk X.J.M.Leijtens J.J.G.M.van derTol M.K.Smit 《Photonics Research》 SCIE EI 2015年第5期60-68,共9页
InP integrated photonics has become a critical enabler for modern telecommunications, and is poised to revolutionize data communications, precision metrology, spectrometry, and imaging. The possibility to integrate hi... InP integrated photonics has become a critical enabler for modern telecommunications, and is poised to revolutionize data communications, precision metrology, spectrometry, and imaging. The possibility to integrate high-performance amplifiers, lasers, modulators, and detectors in combination with interferometers within one chip is enabling game-changing performance advances, energy savings, and cost reductions. Generic integration accelerates progress through the separation of applications from a common technology development. In this paper, we review the current status in In P integrated photonics and the efforts to integrate the next generation of high-performance functionality on a common substrate using the generic methodology. 展开更多
关键词 mode Invited InP photonic circuits using generic integration
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Reliable iris localization using integral projection function and 2D-shape properties
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作者 Farmanullah Jan Imran Usman Shahrukh Agha 《Chinese Optics Letters》 SCIE EI CAS CSCD 2012年第11期50-55,共6页
Iris recognition technology recognizes a human based on his/her iris pattern. However, the accuracy of the iris recognition technology depends on accurate iris localization. Localizing a pupil region in the presence o... Iris recognition technology recognizes a human based on his/her iris pattern. However, the accuracy of the iris recognition technology depends on accurate iris localization. Localizing a pupil region in the presence of other low-intensity regions, such as hairs, eyebrows, and eyelashes, is a challenging task. This study proposes an iris localization technique that includes a localizing pupillary boundary in a sub-image by using an integral projection function and two-dimensional shape properties (e.g., area, geometry, and circularity). The limbic boundary is localized using gradients and an error distance transform, and the boundary is regularized with active contours. Experimental results obtained from public databases show the superiority of the Drooosed techniaue over contemporary methods. 展开更多
关键词 Reliable iris localization using integral projection function and 2D-shape properties ROI
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Theoretical analysis of a collimated hollow-laser-beam generated by a single axicon using diffraction integral
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作者 钱勇 王育竹 《Chinese Optics Letters》 SCIE EI CAS CSCD 2004年第4期232-234,共3页
A novel method to generate a collimated hollow-laser-beam (HLB) by only a single axicon is proposed. With some reasonable assumptions, the radial light intensity distribution is calculated in detail by diffraction int... A novel method to generate a collimated hollow-laser-beam (HLB) by only a single axicon is proposed. With some reasonable assumptions, the radial light intensity distribution is calculated in detail by diffraction integral theory.The result of numerical simulation shows that this method is valid.Compared with other methods of generating HLB,this scheme is extraordinarily simple in principle and can be utilized experimentally to construct a light trap in atomic fountain for convenience. 展开更多
关键词 HLB Theoretical analysis of a collimated hollow-laser-beam generated by a single axicon using diffraction integral
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