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关键词： Hyperspectral image classification   Deep learning   Multi-grained scanning   MugNet  

摘要： In recent years, deep learning based methods have attracted broad attention in the field of hyperspectral image classification. However, due to the massive parameters and the complex network structure, deep learning methods may not perform well when only few training samples are available. In this paper, we propose a small-scale data based method, multi-grained network (MugNet), to explore the application of deep learning approaches in hyperspectral image classification. MugNet could be considered as a simplified deep learning model which mainly targets at limited samples based hyperspectral image classification. Three novel strategies are proposed to construct MugNet. First, the spectral relationship among different bands, as well as the spatial correlation within neighboring pixels, are both utilized via a multi-grained scanning approach. The proposed multi-grained scanning strategy could not only extract the joint spectral-spatial information, but also combine different grains' spectral and spatial relationship. Second, because there are abundant unlabeled pixels available in hyperspectral images, we take full advantage of these samples, and adopt a semi-supervised manner in the process of generating convolution kernels. At last, the MugNet is built upon the basis of a very simple network which does not include many hyperparameters for tuning. The performance of MugNet is evaluated on a popular and two challenging data sets, and comparison experiments with several state-of-the-art hyperspectral image classification methods are revealed. (C) 2017 International Society for Photogrammetry and Remote Sensing, Inc. (ISPRS). Published by Elsevier B.V. All rights reserved.

关键词： contracting   quality improvement   pay-before-performance   pay-after-performance  

摘要： This study examines different contract forms for the supply chain with quality improvement decision and retailer price decision. We consider three types of quality improvement: cost consuming, cost identical, and cost saving, which correspond to the cases in which quality improvement leads to an increment, no change, and a decrease in production cost, respectively. We compare the performance of two types of quality contracts: (1) pay-before-performance contract, under which the supplier receives monetary support from the buyer before exerting quality improvement effort;and (2) pay-after-performance contract, under which the supplier receives monetary compensation based on the outcome of effort. We find that the performance of each contract depends on the types of quality improvement. Further, the pay-after-performance contract leads to close-to-perfect contract efficiency and dominates the pay-before-performance contract from the supplier's perspective in most cases. However, this result does not apply in two extended cases: when there are multiple competing suppliers, the pay-before-performance contract can dominate the pay-after-performance contract if quality improvement is cost consuming;and when the buyer can exert sales effort, neither contract can achieve close-to-perfect efficiency in most cases.

关键词： aerosol‐cloud interaction   vertical variations   South Asia  

摘要： Changes in anthropogenic aerosol loading affect cloud albedo and the Earth's radiative balance with a low level of scientific understanding. Aerosol-cloud interaction and its effects on climate are mainly evaluated using passive observations in a global scale. Here this study estimated the intrinsic response of clouds to aerosols by combining active and passive satellite observations from July 2006 to February 2011 in South Asia. We evaluate the average radiative forcing by the intrinsic aerosol-cloud interaction for warm liquid clouds as 0.63 +/- 0.19, -0.34 +/- 0.40, and 1.11 +/- 0.08 W/m(2) during the annual, monsoon, and nonmonsoon periods in South Asia, respectively. Relationships derived among liquid water path, cloud droplet number concentration, and consequent cloud albedo are assessed as a function of aerosol concentration. The intensity of the aerosol-cloud interaction gradually weakens with increasing cloud base height above ground level in South Asia, is associated with aerosol vertical distribution and vertical atmospheric upward motion. Moreover, distinct regional and seasonal variations in the aerosol-cloud interaction are observed for liquid water path, cloud droplet number concentration, and the resulting cloud albedo in South Asia. These variations are associated with water vapor and aerosol absorption levels. Results contribute to the understanding and modeling of aerosol-cloud interactions and determining their effects on radiative forcing and climate in South Asia.

关键词： 实验室管理   食品检验   质量体系   工作质量   管理工作   优化  

摘要： 有效的管理可以提升食品检验实验室的工作水平,为进一步保证食品检验工作质量,寻求管理优化十分必要。基于此,本文以食品检验实验室管理的实际问题作为切入点,给予简述,再以此为基础,重点论述质量体系在食品检验实验室管理中的运用方法;给出明确检验计划、加强执行与问题分析、推行循环检验机制等可行建议,借此为后续食品检验实验室管理工作的优化提供必要参考。

关键词： 食品生产   国际化发展   食品检验检测  

摘要： 食品的卫生以及质量安全和人们的健康甚至生命息息相关,因此,需要对食品的卫生质量安全进行系统的检测以及评价。本文主要对食品检验检测所存在的不足进行分析,并提出改进措施,以促进我国的食品安全。

关键词： 痕迹检验技术   交通事故   重要作用  

摘要： 痕迹检验技术隶属于刑事科学技术,它是一种较为常见且极具科学性的侦查技术,在我国刑事案件侦查过程中得以广泛应用。随着近年来我国城市化进程的加快、城市车辆的增加,痕迹检验技术也逐渐应用于交通事故处理过程中,为我国交通事故处理人员带来了极大的便利,在肇事车辆认定、事故责任划分、事故形态判定以及碰撞中心、碰撞顺序方面发挥了重要作用。为了明确痕迹检验技术在交通事故处理中的重要性,以及给相关人士提供有益参考,本文以交通事故处理为视角,对痕迹检验技术应用的重要作用予以分析。

关键词： 口服固体制剂   生物等效性   注册申请   仿制药   样品   分类   化学   国务院办公厅  

摘要： 为贯彻中共中央办公厅、国务院办公厅《关于深化审评审批制度改革鼓励药品医疗器械创新的意见》（厅字[2017]42号）、国务院办公厅《关于改革完善仿制药供应保障及使用政策的意见》（国办发[2018]20号）精神，促进仿制药研发，完善仿制药注册申请的技术标准，保证商业化生产批次样品与生物等效性研究批次样品质量与疗效的一致性，国家药审中心起草制定了《注册分类4、5．2类化学仿制药（口服固体制剂）生物等效性研究批次样品批量的一般要求（试行）》，予以发布。

关键词： 柴达木地区   枸杞   检验方法   干制   水分   贮存   成熟果实   大陆性气候  

摘要： 柴达木干制枸杞为产自柴达木地区的茄科植物枸杞（Lyciumbarbaru）的干燥成熟果实,是我国传统常用药食同源材料.由于青海柴达木盆地独具特色的高原大陆性气候,光照时间长达10小时,昼夜温差大,拥有丰富而独特的光、热、水、土资源,使得柴达木枸杞鲜果玲珑剔透,色红粒大,果实卵圆形,籽少、肉厚,大小均匀,无碎果,无霉变,无杂质,品质优良,是我国传统的出口食品之一.

关键词： 医疗保险   居民医疗支出   释放效应   减负效应  

摘要： 本文在定义医疗保险的"释放效应"和"减负效应"的基础上分析了其对居民个人医疗支出的影响机理,并利用2003—2014年中国30个省份的城镇面板数据进行了实证检验。研究结果表明:医疗保险与城镇居民个人医疗支出呈"倒U曲线"的关系,即医疗保险水平较低时只能发挥"释放效应",只有当医疗保险提高到一定水平的时候才能发挥"减负效应";高的收入水平可以缓解医疗保险发挥"释放效应"的压力,促使医疗保险在一个较低的水平上实现"减负效应",因此当前的医疗保险政策具有亲富人的特征。分区域的实证研究发现,东部地区的医疗保险水平已经发挥了"减负效应",西部地区医疗保险仍主要表现为"释放效应"。政策建议方面,在加大医疗保险投入力度的同时,应重视针对不同收入水平的人群和地区实施有差别的医疗保险政策。

关键词： 暴雨   急流   超低空急流脉动   模式预报检验  

摘要： 利用NCEP fnl 1°×1°全球资料、常规气象观测资料和风廓线雷达资料,从急流角度入手对2014年5月16-18日江西中北部地区的暴雨过程进行诊断分析。结果表明,超低空、低空急流的加强为暴雨区持续提供能量以及水汽,且急流前端辐合抬升加强了上升运动;高空200 h Pa我国东北地区低涡和南亚高压配合形成的分流区产生的辐散作用对降水存在促进作用;超低空急流脉动有利于强降水的产生;高、低空急流的适宜配置产生的动力场耦合作用,为大暴雨的发生、发展提供非常有利的动力条件。对模式风场预报检验发现,模式预报稳定性较好,但是模式预报在急流核强度上与实况存在一些差别。