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关键词： Face recognition   Virtual face images   Representation classification   Principal component analysis  

摘要： Classifiers such as sparse representation or collaborative representation can get good performance in face recognition. But these methods require a number of train samples in each class to construct the dictionary. On the condition of undersampled train samples, their performance decreases dramatically. A novel method is proposed in this paper to address undersampled face recognition problem. Firstly, virtual face images are generated by principal component analysis and mirror transform. Secondly, the test sample is collaboratively represented by the augmented train samples and is recognized by classifier based on representation. A number of face recognition experiments on three benchmark face database show that the recognition accuracy of our method is greater than that of a similar method, while time efficiency of our method is competitive to similar method.

关键词： smallholder   coffee forest   vulnerability   El Nino   Ethiopia  

摘要： Smallholder farmers dependent on rain-fed agriculture are particularly vulnerable to extremeclimate events and, therefore, it is necessary to identify adaptive measures thatwould increase farmer resilience to these shocks. Themanagement options in a low-input system, like forest coffee (Coffea arabica), arelimited and there are several factors out of farmers' control driving their vulnerability to changing climatic conditions. These can relate to social structures and landscape factors, which can interact to reduce farmers' adaptive capacity, creating a state of contextual vulnerability. We explored the potential synergies of this interaction across elevation, patch area and shade management gradients for smallholder coffee farms around theUNESCOYayu Coffee Forest BiosphereReserve in Ethiopia before, during and immediately following the 2015/16 El Nino. We documented a dramatic collapse in coffee yields across all farms, resulting in coffee incomes 29.5% +/- 18.0% and 19.5% +/- 10.0% of 2014 incomes in 2015 and 2016, respectively. We identified farms at elevations between 1500 and 1600mwith canopy openness between 40% and 45% as being consistently lowyielding over our study period. We found these farmers had the highest rates of income diversification and, therefore, were already exhibiting adaptive capacity. Farmerswith the largest income losses were spatially concentrated between 1600 and 1700m, located in larger patch areas with lower canopy openness. Farmers at this elevation have access to poor infrastructure, restrictions on shademanagement and reported higher dependence on incomefromcoffee, indicating an interaction of biotic and social factors exacerbating their vulnerability. Unfortunately, due to a nationally declared state of emergency, wewere unable to survey farmers on the adaptivemeasures they undertook;therefore, we are limited in assessing their resilience. However, we do show the importance of considering both biotically and socially-mediated influe

关键词： ELECTRIC lines   TIMBERLINE   SYSTOLIC blood pressure   BLOOD pressure   CAROTID artery   HEMODYNAMICS  

摘要： We developed a whole-circulation computational model by integrating a transmission line (TL) model describing vascular wave transmission into the established CircAdapt platform of whole-heart mechanics. In the present paper, we verify the numerical framework of our TL model by benchmark comparison to a previously validated pulse wave propagation (PWP) model. Additionally, we showcase the integrated CircAdapt-TL model, which now includes the heart as well as extensive arterial and venous trees with terminal impedances. We present CircAdapt-TL haemodynamics simulations of: 1) a systemic normotensive situation and 2) a systemic hypertensive situation. In the TL-PWP benchmark comparison we found good agreement regarding pressure and flow waveforms (relative errors <= 2.9% for pressure, and <= 5.6% for flow). CircAdapt-TL simulations reproduced the typically observed haemodynamic changes with hypertension, expressed by increases in mean and pulsatile blood pressures, and increased arterial pulse wave velocity. We observed a change in the timing of pressure augmentation (defined as a late-systolic boost in aortic pressure) from occurring after time of peak systolic pressure in the normotensive situation, to occurring prior to time of peak pressure in the hypertensive situation. The pressure augmentation could not be observed when the systemic circulation was lumped into a (non-linear) three-element windkessel model, instead of using our TL model. Wave intensity analysis at the carotid artery indicated earlier arrival of reflected waves with hypertension as compared to normotension, in good qualitative agreement with findings in patients. In conclusion, we successfully embedded a TL model as a vascular module into the CircAdapt platform. The integrated CircAdapt-TL model allows detailed studies on mechanistic studies on heart-vessel interaction.

关键词： FannDESIGN model   Farmer livelihoods   Labor   Multi-objective optimization   Nutrition   Soil organic matter  

摘要： Farm models have the potential to describe farming systems and livelihoods, identify trade-offs and synergies, and provide ex-ante assessments of agricultural technologies and policies. We developed three new modules related to budget, labor, and human nutrition for the bio-economic whole-farm model 'FarmDESIGN'. The expanded model positions the fanning enterprise within the farm household. We illustrate the model's new capabilities for farm households in two villages in Northwest Vietnam, where we conducted multi-objective optimization to identify options for improving the farm households' current performance on key sustainability and livelihood indicators. Modeling results suggest trade-offs between environmental, economic, and social objectives are common, although not universal. The new modules increase the scope for modeling flows of resources (namely cash, labor, and food) between the farm enterprise and the farm household, as well as beyond the farm gate. This allows conducting modeling explorations, optimization routines, and scenario analyses in farming systems research.

关键词： Data augmentation   deep learning   generative adversarial networks (GANs)   scene classification  

摘要： Lack of annotated samples greatly restrains the direct application of deep learning in remote sensing image scene classification. Although research studies have been done to tackle this issue by data augmentation with various image transformation operations, they are still limited in quantity and diversity. Recently, the advent of the unsupervised learning-based generative adversarial networks (GANs) brings us a new way to generate augmented samples. However, such GAN-generated samples are currently only served for training GANs model itself and for improving the performance of the discriminator in GANs internally (in vivo). It becomes a question of serious doubt whether the GAN-generated samples can help better improve the scene classification performance of other deep learning networks (in vitro), compared with the widely used transformed samples. To answer this question, this letter proposes a SiftingGAN approach to generate more numerous, more diverse, and more authentic labeled samples for data augmentation. SiftingGAN extends traditional GAN framework with an Online-Output method for sample generation, a GenerativeModel-Sifting method for model sifting, and a Labeled-Sample-Discriminating method for sample sifting. Experiments on the well-known aerial image data set demonstrate that the proposed SiftingGAN method can not only effectively improve the performance of the scene classification baseline that is achieved without data augmentation but also significantly excels the comparison methods based on traditional geometric/radiometric transformation operations.

关键词： Chemiluminescence detection   Gas chromatography   Nitrosamines   Discrimination analysis  

摘要： The problems of contamination of many products by nitroso compounds have been discussed since 1970's and have been partially solved, namely, the contamination by carcinogenic volatile N-nitrosamines. However, there is still a gap in knowing non-volatile nitroso compounds in terms of both the determination of these compounds and the description of their toxicity. Therefore, a procedure for their detailed non-targeted study is necessary to be developed. Based on these facts, a new method permitting the detection and the classification of nitroso compound groups, such as N-nitroso, C-nitroso, and interfering substances in the nitrosamine specific chemiluminescence detection after previous gas chromatographic separation, was developed. The method is based on signal profiling of chromatographic peaks recorded by a chemiluminescence detector at different pyrolytic temperatures and subsequent multivariate chemometric classification. The resulting classification function by linear discriminant analysis shows good performance with total accuracy of 96.12% after the method validation. The method was successfully applied and demonstrated on a non-targeted beer sample analysis. Nitroso compounds detected by the method were selected for detailed structural analysis by GC-MS/MS. The combination of the presented method with the MS/MS instrumentation provides a really powerful analytical tool for the identification of unknown nitroso compounds in complex samples. This study represents a valuable contribution to the protocols of identification of organic compounds with the nitrogen functional groups - toxicologically and analytically important nitroso compounds. (C) 2019 Elsevier B.V. All rights reserved.

关键词： 受伤运动员   运动康复   遵医意图   计划行为理论   模型检验  

摘要： 以计划行为理论为基础,选取中国19个省市专业队的350名正在接受治疗的受伤运动员作为研究对象,现场匿名填写计划行为量表、行动计划量表、预期后悔量表及遵医行为量表,构建并检验受伤运动员遵医行为混合模型,揭示受伤运动员康复遵医意图与行为的作用机制。结果显示:①在计划行为理论传统的3个行为意图前因变量中,仅主观规范能有效预测康复遵医行为意图;②行动计划在行为意图与遵医行为之间起部分中介作用;③预期后悔对行为意图与遵医行为之间关系的调节作用通过行动计划的前半部分中介实现。提示:①对于受伤运动员而言,周围重要人物(主观规范)能够显著影响其康复遵医意图;②某些受伤运动员需要通过制订行动计划才能促成遵医行为的实现,另一些则不需要;③相对于预期后悔评分较低的受伤运动员,间接效果对预期后悔评分较高的受伤运动员的影响更显著。

关键词： 教育收益   个体幸福感   中介因素   性别差异  

摘要： 基于个体的教育收益不仅包括以工资收入反映出来的经济回报,还涵盖了涉及人类生存各方面的非经济收益,倍受关注的个体幸福感也是其中之一。以中国综合社会调查2012年的全国数据为基础,对教育是否能够提升个体幸福感及其提升的作用机制进行了研究。结果显示:教育能够促进个体幸福感的提升;个体的健康水平、个体的社会地位、个体的休闲程度和个体的人际关系都可以部分地解释教育提升个体幸福感指数的作用,其部分中介效果成立;个体职业收入这一变量的部分中介效果只在男性子样本中成立,在女性子样本中不成立。

关键词： 全血C反应蛋白   血常规   细菌性感染性   诊断作用  

摘要： 目的主要研究说明CRP、血常规检验的可行性,此方式应用在儿科当中,观察其情况。方法选取我院60例患儿作为分析的对象,参照组开展血常规,实验组开展血常规外,再检验CRP,综合分析其各项情况。结果实验组肺炎的情况占比8/30,肠炎的情况占比5/30,尿路感染的情况占比10/30,脑膜炎的情况占比6/30,其检测正确的情况为29/30,错误的情况为1/30;参照组肺炎的情况占比5/30,肠炎的情况占比4/30,尿路感染的情况占比9/30,脑膜炎的情况占比2/30,其检测正确的情况为20/30,错误的情况为10/30。不同组具有较大的不同(P<0.05)。结论应用实验组的方式,其检验中所具有的问题少,正确性高。

关键词： 制造业投入服务化   出口技术复杂度   技术创新  

摘要： 制造业投入服务化作为制造业和服务业连接的纽带是出口产品技术复杂度提升的重要动力。本文采用WIOD数据库,CEPII的BACI数据库以及中国工业企业数据库的匹配数据,基于Hausmann等核算出口产品技术复杂度的方法,实证分析了制造业投入服务化对于出口产品技术复杂度的作用机制。结果表明:制造业投入服务化能显著促进我国制造业出口技术复杂度的提高;投入服务化可通过技术创新渠道促进制造业出口技术复杂度的提升,且对不同要素密集度制造业而言技术创新渠道作用程度有所不同。