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1.
针对图像稀疏重建中因使用固定参数的全变分(TV)正则项所带来的图像细节缺失和阶梯效应问题,提出了一种自适应二阶广义全变分(TGV)约束的图像稀疏重建算法。该算法采用二阶广义全变分模型权衡图像的一阶导数和二阶导数,且能够根据每次迭代得到的重构解及对应张量函数自适应地修正权重系数,实现图像的稀疏重建。与全变分正则模型和固定参数广义全变分正则模型相比,该算法能更好地保持图像轮廓和细节信息,提高重建图像的峰值信噪比(PSNR)和结构相似度(SSIM)。  相似文献   

2.
针对统计非局部均值滤波损坏图像的细节与鲁棒性双边带滤波去噪不充分的缺点,提出了一种基于统计非局部均值滤波与鲁棒性双边带滤波相结合的复合滤波算法。该复合滤波算法通过统计非局部均值滤波与鲁棒性双边带滤波线性组合,利用Stein无偏风险估计对复合算法中的参数进行估计。实验中,从主观与客观方面进行对比分析,证明所提出的复合算法体现了非局部均值滤波与双边带滤波的优点,能有效地去除噪声并更好地保留图像的细节信息,峰值信噪比提高1~2 dB。  相似文献   

3.
为了提高鲁棒无损信息隐藏算法容量,利用多光谱图像谱段间的相关性及其小波变换高频系数分块均值的稳定性,提出一种变换域统计量移位的鲁棒无损信息隐藏算法。首先,在光谱方向采用Karhunen Loêve变换(KLT)去相关,然后对得到的KLT本征子图像进行离散小波变换,将小波HH高频系数分块均值作为统计量,通过其直方图移位来隐藏秘密信息,最后将浮点数变换和像素溢出引起的误差嵌入含密图像中以便对恢复的载体图像进行误差补偿。实验结果表明:在图像质量和以往算法相当的情况下,该算法的隐藏容量增加了1倍,并且能抵抗噪声攻击;而与最新算法相比,在隐藏容量相同时,该算法抗JPEG2000压缩倍数平均提高23.9%,误码率平均降低了44.8%。  相似文献   

4.
针对现有技术不能解决机载可见光图像快速自动定位的问题,提出了一种定位精度高、处理速度快、可扩展性好的机载可见光图像定位方法。该方法以传感器共线成像模型为中心,将实时图像和传感器成像参数送入共线模型进行正射校正,校正后的图像与相应的基准图像进行图像配准,使用配准同名点信息更新传感器成像参数,最后再次通过共线模型获取实时图地理坐标定位信息。这种通过图像配准再计算成像模型的间接定位方法,不仅减少了计算量,而且使自动配准算法稳定,较传统的直接定位方法或图像配准方法有突出的优势。此外,该方法具有严格的误差传递计算公式,能计算定位结果的误差。仿真实验表明即使在大倾斜角条件下,该方法也能获得优于100 m的定位精度。  相似文献   

5.
机场跑道场景下,由于雾、霾等恶劣天气以及大气散射的作用,使拍摄的图像对比度降低,颜色退化,物体特征难以辨认,影响机场跑道图像的异物检测与识别,带来一些安全隐患。针对上述问题,提出基于双线性插值和中值滤波的改进的引导滤波算法,提高图像对比度和处理速度,利于机场跑道异物检测与识别。仿真结果表明,改进的引导滤波算法与已有算法相比,处理速度提高了2~3倍,且图像彩色值分布更广,直方图更均匀。该算法拥有良好的边缘保持性,在细节增强方面有很好的指导意义。随后将改进的引导滤波算法移植到数字信号处理器(DSP)平台上,以满足实际工程应用对小型化的需求。  相似文献   

6.
激光光斑图像是用来评价激光光束质量的重要依据,在光电信息转换处理中有着较为重要的应用。为进一步优化激光光斑图像的信噪比,提出了一种激光光斑图像的去噪算法,通过双向加权的维纳滤波,改善了获取的激光光斑图像的信噪比。和加权中值滤波,维纳滤波相比,在图像峰值信噪比、信息熵值和结构相似度都取得了一定程度的增益。算法可以进一步清晰光斑图像,从而能够使激光探测的后续分析更加准确。  相似文献   

7.
局部变分有效地增强图像的轮廓信息,但不可避免地模糊图像的细节并在平滑区域产生阶梯效应。非局部变分能有效重构图像的纹理信息,但同时会破坏图像的结构轮廓信息。考虑到局部与非局部变分的互补性,提出了一种基于图像局部梯度与非局部梯度的复合变分模型,并通过Bregman交替迭代极小化图像的局部梯度与非局部梯度的L1范数,使去噪后的图像在去除噪声的同时更好地保留图像的结构与细节信息。对比实验证明,提出的复合变分模型有效地利用了图像的局部变分与非局部变分的优点,在图像评价的主客观方面都表现出了更好的性能。  相似文献   

8.
噪声图像的恢复是影响图像信息提取的一个重要因素。主要针对现存的噪声图像恢复算法在消除细线及椒盐噪声方面的困难,基于待检像素的邻域信息提出了一种针对细线和椒盐噪声感染的图像的恢复算法。实验结果表明,文中所提算法不仅具有很好的抑制细线及椒盐噪声的效果,而且有效地保存了图像的细节与结构信息,同时对其它的噪声也有一定的抑制作用。  相似文献   

9.
针对图像的非局部稀疏表示忽略图像中结构相似信息的缺点,将群稀疏表示引入到图像的最优滤波中,提出了一种有效去除图像高斯噪声的非局部群稀疏表示模型。该模型首先选择图像非局部相似块构建相似矩阵,在群稀疏限制下对相似矩阵进行正交分解得到正交矩阵;在已知噪声服从高斯分布的情况下,再通过求得的正交矩阵结合贝叶斯最小均方误差准则实现对特征矩阵的最优估计;最后通过正交矩阵与特征矩阵重构去噪后的图像。实验对比证明,所提的非局部群稀疏表示的图像去噪模型在去除噪声的同时更好地保留了图像的结构信息,获得了更好的主客观评价指标,去噪的峰值信噪比提高1 dB以上。  相似文献   

10.
介绍了一种新颖的图像融合算法。该方法首先将图像的亮度通道进行分解,然后对分 解后的层使用不同的方式进行处理。该方法使用均值插值法来解决图像融合问题。实验表明 ,该方法在外观不同的图像上能够获得比较满意的结果,融合结果和目标图像的细节纹理匹 配完好且无缝。此外,基于图形处理器(GPU)的并行实现提高了算法的效率。  相似文献   

11.
美国进口商和中国出口商不满美国商务部对来自中国的某些非公路用轮胎实施反倾销和反补贴税的裁定,向美国国际贸易法院提出起诉。美国国际贸易法院裁定,美国法律没有明确规定反倾销税法是否可适用于非市场经济国家;本案中美国商务部做的"双反"裁定,在方法上不合理。本文在介绍该案的基本案情、归纳法院推理和判决的基础上,对该案涉及的法律问题做了简要评论。  相似文献   

12.
In this study, we evaluate how the effect of customers' experiences on revisit intention for non-indigenous restaurants can be moderated by economic distance (ED), cultural distance (CD) and global-connectedness distance (GD) between the country of origin for a given non-indigenous restaurant and the customer’s resident country. Surveys were conducted in seven countries across three continents, and the levels of ED, CD and GD between Korea and the seven countries were used as moderators. The findings suggest that the types of food and staff are two elements that should be emphasized in countries that are relatively close to Korea. Conversely, elements like the atmosphere of the restaurant and word of mouth should be emphasized in countries that have greater distances from Korea. Of the three distances considered in the study, GD had the strongest moderating effect on the relationship between customers’ experiences and their intentions to return to the restaurant. As a whole, the results imply that ED, CD and GD are important points of reference when considering prior experience while selecting a target country based on the strength of the restaurant’s experience management.  相似文献   

13.
This paper addresses the important question of whether public investment spending on economic infrastructure enhances economic growth in Mexico. It estimates a Cobb-Douglas production function that includes public infrastructure capital. Using cointegration analysis, the paper estimates a vector error correction model (VECM) for the 1995?–?99 period. The results suggest that there is a long-term stable relationship among the variables included in the VECM. The evidence also indicates that both public infrastructure spending and private capital formation have a positive and highly significant effect on the rate of output growth. Finally, the impulse response functions (IRF) and the variance decompositions (VDC) of the endogenous variables in the VECM suggest that the response of private capital to public infrastructure is positive while the reverse causation is not affirmed. From a policy standpoint, the findings call into question stabilization policies that disproportionately reduce public infrastructure to meet targeted reductions in the fiscal deficit (JEL, O1, O47, O54).  相似文献   

14.
Unlike previous studies which only focus on the main effect between IC and FV, this research includes PTE with the gap of resource-based view. IC is a key element in creating a competitive advantage, as it has a great influence on FV. A company may put relatively less into IC if it demonstrates higher efficiency. However, previous studies have neglected the fact that relative efficiency and IC affect FV and stock returns directly and indirectly. The research period was from 2006 to 2010 and the main research methods include HRA and DEA. The main research findings include the following. (1) There is a space for improvement in terms of the total technical efficiency. (2) PTE has a significant moderating effect between IC and FV. (3) IC and PTE have a significant influence on FV. (4) Apart from PTE and stock returns, IC and FV show significant differences within the sub-industry.  相似文献   

15.
文章根据风险调整收益(RAROC)的原理,借鉴J.P.摩根的信用计量CreditMetrics模型中信用等级转移的思想,构建了应收账款回收期内受信企业信用状况转移矩阵,并据此计算出企业信用VaR值和经济资本CaR值,进而计算RAROC比值,可为企业信用销售决策提供依据。通过将RAROC方法引入企业信用风险管理体系,可以对企业经营活动进行基于风险的绩效考核和业绩评价,以期提高企业信用风险管理水平。  相似文献   

16.
采用高效液相色谱(HPLC)与电感耦合等离子体质谱(ICP-MS)联用技术,建立了粉质化妆品中六价铬的测定方法。样品经0.05 mol/L氢氧化纳溶液超声振荡提取;HPLC采用Hypersil GOLD C18柱分离,以5%(v/v)甲醇-2 mmol/L四丁基硫酸氢铵水溶液(pH 4.0)作为流动相;ICP-MS测定选用碰撞池技术以消除40Ar12C对52Cr的谱学干扰。方法学研究结果表明,添加水平为0.040-2.000 mg/kg时,回收率为77.5%-107.5%,相对标准偏差(RSD)小于10%。  相似文献   

17.
张岳松 《商业研究》2006,4(2):69-74
供应链管理和虚拟企业是已经在世界范围所采用的概念。这些概念包括一系列管理、组织和技术问题,公司为了提高竞争能力,开拓市场机遇,建立合作联盟。供应链管理是一种集成的管理思想,从战略上整体地整合供应商和顾客。虚拟企业是一种动态的临时组织形式,不同的企业为了开拓商业机遇而通过合作弥补自身竞争力的不足。虽然他们有各自的特点,但是也有共同点。  相似文献   

18.
In recent years, there has been an exponential increase in the amount of foreign investment by emerging market multinational enterprises (EMNEs). While it has been debated whether EMNEs strengthen or weaken the institutions in host countries they invest in, the literature has paid limited attention to how EMNE investment impacts corruption in other emerging markets, one of the most significant destinations of EMNEs. Following Hoskisson et al. (2013), we categorize two types of emerging markets as targets of EMNE investment, a) low-income emerging markets and b) middle-income emerging markets, based on their institutional and market development. Building on the theory of firm-specific advantages (FSAs) and the institutional advantage (IA) of EMNEs, we reason that EMNEs enter foreign markets in accordance to where their skills and competencies can be effectively utilized, and this impacts corruption in the host country. We make two key arguments: (1) EMNEs predominantly use their IA in low-income emerging markets, which in the long term increases corruption in the host market, and (2) EMNEs predominantly use their FSAs to gain competitive advantage in middle-income emerging markets, which decreases corruption in the host market. Empirical analysis of Chinese outward FDI from the 2008-2018 period supports our hypotheses. Our research contributes to both the literature on EMNEs and corruption.  相似文献   

19.
ABSTRACT

Building on social-identity theory, the research develops a model for understanding of the impact of consumer identification with a nation on consumers' brand evaluations. It posits that developing-country consumers' identification with a foreign (developed) nation influences three factors—consumer-based brand equity, consumer-based country image, and consumer-based brand credibility. The research was informed by data from 400 Vietnamese consumers in relation to two Japanese brands Sony and Honda and analyzed using structural equation modeling (SEM). The findings show that Vietnamese (developing-country) consumers prefer Japanese (developed-country) brands over domestic brands, when these consumers identify with the developed nation.  相似文献   

20.
Customers voice their negative brand experiences to their family and friends in the form of negative word-of-mouth (NWOM). Web 2.0 enables the sharing of NWOM in electronic format on various social media sites, online customer review forums, and blogs, which is known as negative electronic word-of-mouth (NeWOM). Researchers need to study the spread of NWOM/NeWOM to prevent adverse consequences for companies and suggest an optimal response for its redressal. Existing literature review studies have focused on word-of-mouth (WOM) and electronic WOM (eWOM) and have considered both positive and negative WOM and eWOM concurrently. Past literature reviews have captured the breadth of the WOM domain, ignoring the depth. This research article contains a review of 282 journal papers capturing the depth of the extant literature by focusing solely on ‘negative’ WOM and eWOM (NWOM and NeWOM), and presents a broad view of the NWOM and NeWOM domains using morphological analysis (MA). This will help to conceptualize and categorize the existing state-of-the-art literature into broad dimensions and identify future research opportunities. The MA framework helps to bifurcate this literature into the following four dimensions: (i) nomenclature of NWOM and NeWOM, (ii) antecedents of NWOM/NeWOM, (iii) impacts of NWOM/NeWOM, and (iv) prevention and recovery response to NeWOM. Further dissection of these four dimensions leads to 15 sub-dimensions and 217 variants. Combinations of the 217 variants enable the identification of 550 novel future research opportunities in the area of NWOM and NeWOM.  相似文献   

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