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“X不比Y·Z”三种语义类型的历史来源 被引量:4
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作者 谢仁友 《古汉语研究》 CSSCI 北大核心 2006年第4期21-27,共7页
“X不比Y·Z”是个歧义句式,包含三种语义类型:Ⅰ.陈述差异,Ⅱ.陈述差距,Ⅲ.否定差距。本文认为,类型Ⅰ是宋代以来汉语中一直存在的;类型Ⅱ是五四前后在外语特别是英法德俄等语言的推动下通过功能扩展产生的;类型Ⅲ是在英法德俄... “X不比Y·Z”是个歧义句式,包含三种语义类型:Ⅰ.陈述差异,Ⅱ.陈述差距,Ⅲ.否定差距。本文认为,类型Ⅰ是宋代以来汉语中一直存在的;类型Ⅱ是五四前后在外语特别是英法德俄等语言的推动下通过功能扩展产生的;类型Ⅲ是在英法德俄等外语的直接影响下产生的。 展开更多
关键词 X不比Y·Z 历史来源
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High Extinction Ration Polarization Independent EA Modulator 被引量:1
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作者 孙洋 王圩 +3 位作者 陈娓兮 刘国利 周帆 朱洪亮 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2001年第11期1374-1376,共3页
An electro absorption modulator is fabricated for optical network system.The strained InGaAs/InAlAs MQW shows improved modulation properties,including polarization independent,high extinction ratio (>40dB) and low... An electro absorption modulator is fabricated for optical network system.The strained InGaAs/InAlAs MQW shows improved modulation properties,including polarization independent,high extinction ratio (>40dB) and low capacitance (<0 5pF),with which,an ultra high frequency(>10GHz) can be obtained. 展开更多
关键词 electro absorption MODULATOR polarization independence
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Improved hybrid iterative optimization method for seismic full waveform inversion
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作者 王义 董良国 刘玉柱 《Applied Geophysics》 SCIE CSCD 2013年第3期265-277,357,358,共15页
In full waveform inversion (FWI), Hessian information of the misfit function is of vital importance for accelerating the convergence of the inversion; however, it usually is not feasible to directly calculate the He... In full waveform inversion (FWI), Hessian information of the misfit function is of vital importance for accelerating the convergence of the inversion; however, it usually is not feasible to directly calculate the Hessian matrix and its inverse. Although the limited memory Broyden-Fletcher-Goldfarb-Shanno (L-BFGS) or Hessian-free inexact Newton (HFN) methods are able to use approximate Hessian information, the information they collect is limited. The two methods can be interlaced because they are able to provide Hessian information for each other; however, the performance of the hybrid iterative method is dependent on the effective switch between the two methods. We have designed a new scheme to realize the dynamic switch between the two methods based on the decrease ratio (DR) of the misfit function (objective function), and we propose a modified hybrid iterative optimization method. In the new scheme, we compare the DR of the two methods for a given computational cost, and choose the method with a faster DR. Using these steps, the modified method always implements the most efficient method. The results of Marmousi and overthrust model testings indicate that the convergence with our modified method is significantly faster than that in the L-BFGS method with no loss of inversion quality. Moreover, our modified outperforms the enriched method by a little speedup of the convergence. It also exhibits better efficiency than the HFN method. 展开更多
关键词 Full waveform inversion Hessian information limited memory BFGS method Hessian-free inexact Newton method decrease ratio
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Catchment-based Imperviousness Metrics Impacts on Floods in Niushou River Basin,Nanjing City,East China 被引量:1
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作者 SU Weizhong DUAN Hongtao 《Chinese Geographical Science》 SCIE CSCD 2017年第2期229-238,共10页
Concerns regarding urbanization impacts on floods gradually moved from end-of-pipe solutions, based on open channel hydraulics improvement, to imperviousness ratio limiting and then to land use control and to integrat... Concerns regarding urbanization impacts on floods gradually moved from end-of-pipe solutions, based on open channel hydraulics improvement, to imperviousness ratio limiting and then to land use control and to integrated planning at local and large scale levels. The Niushou River basin is one of the fastest urbanizing areas in Nanjing City, East China, however, the high urban land percentage has leaded to series of flooding events. The paper aims to reveal the impact of imperviousness ratio, patterns and drainage system on flooding areas based on the unit of catchment and Storm Water Management Model(SWMM). The following conclusions were reached. 1) The ratio or spatial characteristics of the impervious surface affected the runoff volumes and associated floods areas. Despite the well-established drainage system, the high imperviousness ratio, particularly clustered pattern in locations such as hydrological sensitive zones aggravated the flooding tension across the basin. 2) The poor drainage hydraulic efficiency in local areas, and the lack of integral processes of infiltration, yield, storage and discharge in local catchment and larger basin are also significant factors. 3) The Niushou River basin development should improve the drainage transformations from a single local, short-term drainage process into integral, elastic processes of infiltration, yield, storage, and discharge. 展开更多
关键词 imperviousness ratio (IR) imperviousness pattern floods areas catchment system Niushou River basin
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Comparison of New Maize Cultivars at Different Altitudes
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作者 陆顺生 曾林 +3 位作者 段再燕 宋云飞 刘艳 单艳 《Agricultural Science & Technology》 CAS 2016年第9期2030-2036,共7页
[Objective] This study aimed to meet the demand of farmers for highyielding, high-quality, wide-adaptability and multi-resistant new maize cultivars, and to make food production grow continuously. [Method] Comparative... [Objective] This study aimed to meet the demand of farmers for highyielding, high-quality, wide-adaptability and multi-resistant new maize cultivars, and to make food production grow continuously. [Method] Comparative test of new maize cultivars was conducted at different altitudes in 2015, and the yield, main economic characters, agronomic traits, growth period and resistance of maize cultivars were analyzed. [Result] Ruidan 26 and Yongrui 16 can be cultivated in the areas below the altitude of 2 200 m; Huaxingdan 88 can be cultivated in the areas below the altitude of 1 750 m; the other new maize cultivars still need to be tested further. [Cenclusion] The research results can be applied in this area and other similar areas, which will effectively promote the upgrading of maize cultivars and improve the yield per unit area. 展开更多
关键词 New maize cultivar Comparative test Different altitudes
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Research on the measurement of belt speed by video in coal mine based on improved template matching algorithm 被引量:1
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作者 ZHU Ai-chun HUA Wei +1 位作者 WANG Chun WANG Yong-xing 《Journal of Coal Science & Engineering(China)》 2011年第4期469-474,共6页
In order to improve the intelligence of video monitoring system of belt and make up the deficiency of higher failure rate and bad real-time performance in the traditional systems of measurement of belt speed, accordin... In order to improve the intelligence of video monitoring system of belt and make up the deficiency of higher failure rate and bad real-time performance in the traditional systems of measurement of belt speed, according to the fact that the light of coal mine is uneven, the strength of light changes greatly, the direction of belt movement is constant, and the position of camera was fixed, various algorithms of speed measurement by video were studied, and algorithm for template matching based on sum of absolute differences (SAD) and correlation coefficient was proposed and improved, besides, the tracking of feature regions was realized. Then, a camera calibration method using the invariance of the cross-ratio was adopted and the real-time measurement of belt speed by the hardware platform based on DM642 was realized. Finally, experiment results show that this method not only has advantages of high precision and strong anti-jamming capability but also can real-time reflect the changes of belt speed, so it has a comprehensive applicability. 展开更多
关键词 speed measurement by video template matching algorithm DM642 invariance of cross-ratio
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Studies of B_s^O→η′η′ Decays in pQCD Approach
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作者 LIU Xin XIAO Zhen-Jun WANG Hui-Sheng 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第4期981-986,共6页
We calculate the CP averaged branching ratios and CP-violating asymmetries for Bs^0 → η'η' and η'η' decays in the perturbative QCD (pQCD) approach here. The pQCD predictions for the C P-averaged branchin... We calculate the CP averaged branching ratios and CP-violating asymmetries for Bs^0 → η'η' and η'η' decays in the perturbative QCD (pQCD) approach here. The pQCD predictions for the C P-averaged branching ratios are Br(Bs^0 → ηη)=(14.2-7.5^+18.0) ×10^-6,Br(Bs^0 → ηη')=(12.4-7.0^+18.2)×10^-6,and Br(Bs^0 → η'η') =(9.2-4.9^+15.3)×10^-6, which agree well with those obtained by employing the QCD factorization approach and also be consistent with available experimental upper limits. The gluonic contributions are small in size: less than 7% for Bs →ηηand ηη' decays, and around 18% for Bs →η'η' decay. The CP-violating asymmetries for three decays are very small: less than 3% in magnitude. 展开更多
关键词 branching ratio CP-violating asymmetry perturbative QCD
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Rate Control for MPEG-4 Bit Stream
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作者 王振洲 李桂苓 《Transactions of Tianjin University》 EI CAS 2003年第4期279-282,共4页
For a very long time video processing dealt exclusively with fixed-rate sequences of rectangular shaped images. However, interest has been recently moving toward a more flexible concept in which the subject of the pro... For a very long time video processing dealt exclusively with fixed-rate sequences of rectangular shaped images. However, interest has been recently moving toward a more flexible concept in which the subject of the processing and encoding operations is a set of visual elements organized in both time and space in a flexible and arbitrarily complex way. The moving picture experts group (MPEG- 4) standard supports this concept and its verification model (VM) encoder has adopted scalable rate control (SRC) as the rate control scheme, which is based on the spatial domain and compatible with constant bit rate (CBR) and variable bit rate (VBR). In this paper,a new rate control algorithm based on the DCT domain instead of the pixel domain is presented. More-(over), macroblock level rate control scheme to compute the quantization step for each macroblock has been adopted. The experimental results show that the new algorithm can achieve a much better result than the original one in both peak signal-to-noise ratio (PSNR) and the coding bits, and that the new algorithm is more flexible than test model 5 (TM5) rate control algorithm. 展开更多
关键词 moving picture experts group verification model scalable rate control constant bit rate variable bit rate
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B→a_0(1450)ρ(ω) Decays in Perturbative QCD Approach
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作者 张志清 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第12期1063-1070,共8页
In the two-quark model supposition for the meson ao(1450), which can be viewed as either the first excited state (scenario I) or the lowest lying state (scenario II), the branching ratios and the direct CP-viola... In the two-quark model supposition for the meson ao(1450), which can be viewed as either the first excited state (scenario I) or the lowest lying state (scenario II), the branching ratios and the direct CP-violating asymmetries for decays B→a0(1450)ρ(ω) are studied by employing the perturbative QCD factorization approach. We find the following results: (a) For the decays B- B→a0(1450)ρ- andB→a0^+(1450)ρ^-, their branching ratios have large difference between two scenarios. Although their branching ratios are larger than other considered decay modes, their direct CP-violating asymmetries in both scenarios are small. (b) For the decays B-→a0^-(1450)ρ0 and B0→ a0(1450)ρ+, a0^0(1450)ρ0, a00 (1450)w, their branching ratios are dose to each other between two scenarios, respectively. (c) Comparing with the decays a0^0(1450)ρ0,π0ρ0 π0π0, the decay B-→a0^-(1450)ρ0 receives a larger branching ratio in each scenario, which is sensitive to the variation of the Cabibbo-Kobayashi-Maskawa angle α. 展开更多
关键词 DECAY scalar meson perturbative QCD branching ratio CP-asymmetry
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Scaling Equation for Invariant Measure
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作者 LIUShi-Kuo FUZun-Tao 《Communications in Theoretical Physics》 SCIE CAS CSCD 2003年第3期295-296,共2页
An iterated function system (IFS) is constructed. It is shown that the invariant measure of IFS satisfies the same equation as scaling equation for wavelet transform (WT). Obviously, IFS and scaling equation of WT bot... An iterated function system (IFS) is constructed. It is shown that the invariant measure of IFS satisfies the same equation as scaling equation for wavelet transform (WT). Obviously, IFS and scaling equation of WT both have contraction mapping principle. 展开更多
关键词 invariant measure iterated system scaling equations wavelet transform
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Bound States for Hypercentral Singular and Exponential Potentials
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作者 A.A. Rajabi 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第4期669-674,共6页
With a view to obtaining an exact closed form solution to the Schroedinger equation for a variety of hypercentral potentials, we investigate further application of an ansatz. This method is good enough for many kinds ... With a view to obtaining an exact closed form solution to the Schroedinger equation for a variety of hypercentral potentials, we investigate further application of an ansatz. This method is good enough for many kinds of potentials, but in this article it applies to a type of the hypercentral singular potentials V(x) = ax^2 + bx^-4+ cx^-6 and exponential hypercentral Morse potential U (x) = Uo ( e^-2ax - 2 e^-ax) for three interacting particles. The Morse potential is used for diatomic molecule while this method will be successfully used for many atomic molecules. The three-body potentials are more easily introduced and treated within the hyperspherical harmonic formalism. The internal particle motion is usually described by means of Jacobi relative coordinates p, A, and R, in terms of three particle positions r1, r2, and r3. We discuss some results obtained by using harmonic and anharmonic oscillators, however the hypercentral potential can be easily generalized in order to allow a systematic anaiysis, which admits an exact solution of the wave equation. This method is also applied to some other types of three-body, four-body, ..., interacting potentials. 展开更多
关键词 hyperspherical harmonic ANHARMONIC THREE-BODY JACOBIAN hypercentral hyperradial
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Information Moment for Chinese Character Recognition
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作者 孙农亮 李明达 +1 位作者 白霄 孟霏 《Journal of Measurement Science and Instrumentation》 CAS 2011年第2期148-151,共4页
Moment invariants firstly introduced by M. K Hu in 1962, has some shortcomings. After counting a large number of statistical distribution information of Chinese characters,the authors put forward the concept of inform... Moment invariants firstly introduced by M. K Hu in 1962, has some shortcomings. After counting a large number of statistical distribution information of Chinese characters,the authors put forward the concept of information moments and demonstrate its invariance to translation,rotation and scaling.Also they perform the experiment in which information moments compared with moment invaiants for the effects of similar Chinese characters and font recognition.At last they show the recognition rate of 88% by information moments,with 70% by moment inariants. 展开更多
关键词 information moment Chinese character recognition moment invariants
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Rearrangement Inequality and Chebyshev's Sum Inequality on Positive Tensor Products of Orlicz Sequence Space with Banach Lattice 被引量:1
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作者 Wei-Kai Lai 《Journal of Mathematics and System Science》 2014年第8期574-578,共5页
Let φ be an Orlicz function that has a complementary function φ* and let lφ be an Orlicz sequence space. We prove a similar version of Rearrangement Inequality and Chebyshev's Sum Inequality in lφ FX, the Freml... Let φ be an Orlicz function that has a complementary function φ* and let lφ be an Orlicz sequence space. We prove a similar version of Rearrangement Inequality and Chebyshev's Sum Inequality in lφ FX, the Fremlin projective tensor product of lφ with a Banach lattice X, and in lφ iX, the Wittstock injective tensor product of lφ with a Banach lattice X. 展开更多
关键词 Rearrangement inequality Chebyshev's sum inequality injective tensor product projective tensor product Orlicz sequence space
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The Popularization of the Weighting of Chebysher's Inequality
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作者 YANG Hui YAO Hong 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2005年第4期367-371,共5页
This paper presents the popularization of the weighting of Chebyshev's inequality and discusses the relation between this popularization and some famous inequalities.
关键词 Chebysher's inequality EXTENSION
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B→K^*у/Decay in Top-Quark Two-Higgs-Doublet Model
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作者 XIAO Zhen-Jun CHENG Hui-Hui Lü Lin-Xia 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第5X期895-900,共6页
By employing the QCD factorization approach for the exclusive B→Vу decays, we study the exclusive decay B→K^*у in the top-quark two-Higgs-doublet mode/(T2HDM). Within the considered parameter space, we find the... By employing the QCD factorization approach for the exclusive B→Vу decays, we study the exclusive decay B→K^*у in the top-quark two-Higgs-doublet mode/(T2HDM). Within the considered parameter space, we find the following conclusions (a) A hght charged-Higgs boson with a mass about 200 GeV is clearly excluded by the date of B→K^*у decay, and this lower limit is comparable with that from the inclusive B→X8*у decay; (b) The theoretical predictions for CP asymmetry of B→K^*у in the T2HDM is always less than 1% in size; and (c) The isospin symmetry breaking for B→K^*у decay in the SM and T2HDM considered here is around 6% in size and well consistent with the data and the general expectations. 展开更多
关键词 B meson decay charged-Higgs boson branching ratio CP asymmetry
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Electrogastrography associated with symptomatic changes after prokinetic drug treatment for functional dyspepsia 被引量:11
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作者 Hyun Chul Lim Sang In Lee +1 位作者 Jiande DZ Chen Hyojin Park 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第41期5948-5956,共9页
AIM:To evaluate the effect of prokinetic drugs on electrogastrography(EGG) parameters according to symptomatic changes in patients with functional dyspepsia(FD).METHODS:Seventy-four patients with FD were prospectively... AIM:To evaluate the effect of prokinetic drugs on electrogastrography(EGG) parameters according to symptomatic changes in patients with functional dyspepsia(FD).METHODS:Seventy-four patients with FD were prospectively enrolled in this study between December 2006 and December 2010.We surveyed the patients using a questionnaire on dyspeptic symptoms before and after an 8-wk course of prokinetic drug treatment.We also measured cutaneous pre-prandial and postprandial EGG recordings including percentage of gastric waves(normogastria,bradygastria,tachygastria),dominant frequency(DF),dominant power(DP),dominant frequency instability coefficient(DFIC),dominant power instability coefficient(DPIC),and the ratio of post-prandial to fasting in DP before and after the 8-wk course of prokinetic drug treatment.RESULTS:Fifty-two patients(70%) achieved symptomatic improvement after prokinetic drug treatment.Patients who had normal gastric slow waves showed symptom improvement group after treatment.Postprandial DF showed a downward trend in the symptom improvement group,especially in the itopride group.Post-prandial DP was increased regardless of symptom improvement,especially in the itopride group and mosapride group.Post-prandial DFIC and DPIC in the symptom improvement group were significantly increased after the treatment.The EGG power ratio was increased after treatment in the symptom improvement group(0.50 ± 0.70 vs 0.93 ± 1.77,P = 0.002),especially in the itopride and levosulpiride groups.CONCLUSION:Prokinetics could improve the symptoms of FD by regulating gastric myoelectrical activity,and EGG could be a useful tool in evaluating the effects of various prokinetics. 展开更多
关键词 ELECTROGASTROGRAPHY Functional dyspepsia ITOPRIDE MOSAPRIDE Levosulpiride
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Comparison of two approximal proximal point algorithms for monotone variational inequalities 被引量:1
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作者 TAO Min 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2007年第6期969-977,共9页
Proximal point algorithms (PPA) are attractive methods for solving monotone variational inequalities (MVI). Since solving the sub-problem exactly in each iteration is costly or sometimes impossible, various approx... Proximal point algorithms (PPA) are attractive methods for solving monotone variational inequalities (MVI). Since solving the sub-problem exactly in each iteration is costly or sometimes impossible, various approximate versions ofPPA (APPA) are developed for practical applications. In this paper, we compare two APPA methods, both of which can be viewed as prediction-correction methods. The only difference is that they use different search directions in the correction-step. By extending the general forward-backward splitting methods, we obtain Algorithm Ⅰ; in the same way, Algorithm Ⅱ is proposed by spreading the general extra-gradient methods. Our analysis explains theoretically why Algorithm Ⅱ usually outperforms Algorithm Ⅰ. For computation practice, we consider a class of MVI with a special structure, and choose the extending Algorithm Ⅱ to implement, which is inspired by the idea of Gauss-Seidel iteration method making full use of information about the latest iteration. And in particular, self-adaptive techniques are adopted to adjust relevant parameters for faster convergence. Finally, some numerical experiments are reported on the separated MVI. Numerical results showed that the extending Algorithm II is feasible and easy to implement with relatively low computation load. 展开更多
关键词 Projection and contraction methods Proximal point algorithm (PPA) Approximate PPA (APPA) Monotone variational inequality (MVI) Prediction and correction
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Are we leveling the playing field? Trends and disparities in sports participation among sexual minority youth in Canada
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作者 Marion Doull Ryan J.Watson +2 位作者 Annie Smith Yuko Homma Elizabeth Saewyc 《Journal of Sport and Health Science》 SCIE 2018年第2期218-226,共9页
Purpose: Sports participation and physical fitness are widely beneficial for young people, yet activity levels among young people are declining.Despite growing popular media attention on the participation of sexual mi... Purpose: Sports participation and physical fitness are widely beneficial for young people, yet activity levels among young people are declining.Despite growing popular media attention on the participation of sexual minority(e.g., lesbian, gay, and bisexual) youth in sports and various campaigns to improve the often homophobic climate of sports, there is limited evidence that sexual minority youth participate in sports. Our aim was to provide a current portrait of sports participation among 3 groups of sexual minority youth(e.g., lesbian, gay, and bisexual) in British Columbia, Canada, as well as to document population trends.Methods: Pooled population-level data from British Columbia, Canada(n = 99,373) were used to examine trends and disparities in sports participation among sexual minority and heterosexual youth. Age-adjusted logistic regression models were used to examine changes in participation over time and disparities in participation over time(1998—2013).Results: We found an overall decline in sports participation and physical activity(PA) for all youth. Sexual minority students were less likely to participate in formal sports(with a coach) and informal sports(without a coach) compared with their heterosexual peers. The disparity in participating in informal sports between heterosexual and sexual minority youth has narrowed over time for some sexual orientation groups, whereas the disparity in participating in formal sports has widened over time in some cases.Conclusion: This study provides a comprehensive examination of sports participation among sexual minority youth over the past 15 years.Despite changing societal attitudes and laudable efforts to reduce homophobia in sports, results suggest that there are continued barriers to participation for sexual minority youth. Further research is needed to understand the factors that limit sports participation for these youth and to inform program development. PA is critical to lifelong health and well-being, and thus continued efforts are needed to increase the sports participation of sexual minority youth in particular. 展开更多
关键词 CANADA DISPARITIES Physical activity Sexual minority youth Sexual orientation Sports participation
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Access to Healthy Food Stores for Residents of Aboriginal Reserves in Rural British Columbia
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《Journal of Food Science and Engineering》 2017年第7期342-350,共9页
The rate of food insecurity has increased tremendously over the past decade in Canada. This increase has been more pronounced in rural and remote areas especially among Aboriginal peoples. Substantial studies indicate... The rate of food insecurity has increased tremendously over the past decade in Canada. This increase has been more pronounced in rural and remote areas especially among Aboriginal peoples. Substantial studies indicated that nearly half of the on-reserve Aboriginal households in British Columbia (BC) suffer from some degree of food insecurity. Despite the valuable research about obtaining traditional food, the issue of access to market food has been less discussed in the literature. The aim of this study was to assess the local food environment of on-reserve Aboriginal peoples by using a proximity-based approach tool in terms of access to healthy food stores such as supermarket and grocery stores. In the first stage, the addresses of all healthy food stores were geocoded into a map layer. Then the locations of Aboriginal reserves were geocoded to a separate map layer. In the second stage, using "Closest Facility Analysis" tool in ArcGIS Version 10.3, the distance based on a 15-minute driving time was measured from each reserve to the closest healthy food destination on CanMapRouteLogistics network. The results indicated that 25% of Aboriginal reserves did not have reasonable access to healthy food stores. We concluded that Aboriginal peoples in low access rural reserves with lower socioeconomic status are at potential risk of perpetuate food insecurity. 展开更多
关键词 Food security rural aboriginal reserves network analysis ArcGIS.
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Natural Processes for the Restoration of Dam Removal Disturbances
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作者 David Franklin Polster 《Journal of Environmental Science and Engineering(B)》 2017年第11期564-568,共5页
The Heber River Diversion Dam (Heber Dam) and 3.6 km penstock on Vancouver island, British Columbia, Canada was built in 1953 and by 2009, it had reached the end of its useful life due to the deteriorated wooden str... The Heber River Diversion Dam (Heber Dam) and 3.6 km penstock on Vancouver island, British Columbia, Canada was built in 1953 and by 2009, it had reached the end of its useful life due to the deteriorated wooden structures. A decision was taken to remove the dam, return the flows in the Heber River to pre-dam conditions and restore the footprint of the dam and penstock. Plans were developed for removal of the dam and contaminated materials including the creosote coated wooden penstock and other wooden structures associated with the dam and site restoration. Work on removal and restoration was undertaken over the summer and fall of 2012 and the spring of 2013. Restoration treatments were based on the use of natural processes as a model for recovery. The recovery of dam and penstock removal disturbances was initiated in the late summer and fall of 2012 with the fall dispersal of seeds from mature pioneering species that formed a significant part of the local undisturbed vegetation. This paper describes the treatments that were applied to enhance the natural recovery of the disturbed areas and the results of those treatments. The restoration treatments were designed to address the filters that were present in project areas. These were identified during an initial inspection in 2009 and were centred on compaction of substrates and a lack of micro-sites. In addition to the use of natural processes for the restoration of project disturbances, a local First Nations crew was hired to transplant sword ferns (Polystichum munitum (Kaulf.) C. Presl) from the adjacent forest areas onto project sites to provide a social benefit from the restoration work. 展开更多
关键词 Natural processes dam removal.
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