基于高效边缘检测的彩色图像灰度化算法

为了使彩色图像灰度化后能更好地保留原始对比度和细节特征,课题组提出一种基于高效边缘检测的彩色图像灰度化算法。课题组通过对线性参数模型产生的一系列备选图像采用像素差值网络（pixel difference networks, PiDiNet）实现鲁棒性、准确性的边缘检测,边界点数最多的备选图像所对应的权重则被选为映射函数的最优解,由于引用了像素差值卷积PDC,对边缘信息敏感度增强。实验结果表明：此算法相比于其他算法能较好地保留原彩色图像的细节特征,使得输出图像轮廓清晰且自然,主客观评价均较优。     

Jokers wild: the importance of humour in the maintenance of organizational culture

Humour may have a number of different effects within organizations, but it is usually manifested in one of two major‘joke forms’: standardized/canned or situation/spontaneous. Using examples of each from fieldwork conducted in a large manufacturing bakery, it is argued that both forms depend for their effect on their appositeness to the‘joke in the social structure’Both forms share the capacity to enable the reversal, within the humorous framework, of problematic social relations, patterns of control, or customary mystifications. Humour may be used to create ambiguity or to promote closure: its impact on the organizational culture will depend on the extent to which the symbolic transformations achieved within its boundaries can be transposed into material,‘real-world’relationships.     

Quantifying Water Pathogen Risk in an Epidemiological Framework

Traditionally, microbial risk assessors have used point estimates to evaluate the probability that an individual will become infected. We developed a quantitative approach that shifts the risk characterization perspective from point estimate to distributional estimate, and from individual to population. To this end, we first designed and implemented a dynamic model that tracks traditional epidemiological variables such as the number of susceptible, infected, diseased, and immune, and environmental variables such as pathogen density. Second, we used a simulation methodology that explicitly acknowledges the uncertainty and variability associated with the data. Specifically, the approach consists of assigning probability distributions to each parameter, sampling from these distributions for Monte Carlo simulations, and using a binary classification to assess the output of each simulation. A case study is presented that explores the uncertainties in assessing the risk of giardiasis when swimming in a recreational impoundment using reclaimed water. Using literature-based information to assign parameters ranges, our analysis demonstrated that the parameter describing the shedding of pathogens by infected swimmers was the factor that contributed most to the uncertainty in risk. The importance of other parameters was dependent on reducing the a priori range of this shedding parameter. By constraining the shedding parameter to its lower subrange, treatment efficiency was the parameter most important in predicting whether a simulation resulted in prevalences above or below non outbreak levels. Whereas parameters associated with human exposure were important when the shedding parameter was constrained to a higher subrange. This Monte Carlo simulation technique identified conditions in which outbreaks and/or nonoutbreaks are likely and identified the parameters that most contributed to the uncertainty associated with a risk prediction.     

Sports PR in message boards on Major League Baseball websites

Message boards are possible places for sports fans to actively express and exchange their opinions. The purpose of this study is to explore the typology of message board uses on sports websites. The analysis of 1350 topics on eight Major League Baseball teams’ websites for 10 days revealed that: (1) the cognitive need of using message boards in a sports organization's website was an outstanding motivation; (2) sharing opinions was a new motivation category (compared to traditional uses and gratifications) that was found to be dominant; and (3) winning teams and losing teams’ message boards were significantly different in terms of number of topics, number of users, and optimism score; however, messages seemed to be optimistic. Implications for public relations practitioners suggest that the message board is an excellent monitoring tool for them as well as a fine communication tool between sports organizations and fans.     

透视星座文化流行背后的秘密

星座文化以神秘时尚、内容丰富、先验预测的形象出现,吸引了众多青少年的关注。现代青少年迫切希望认识自我、了解他人、把握未来,这是星座文化得以流行的重要原因。星座文化的流行对青少年具有满足需要、缓解压力等积极功能。但对星座文化的过度迷恋实质是一种迷信,应该采取有效措施,满足青少年发展的现实需求,引导青少年树立科学的世界观,引领和帮助青少年健康成长。     

Modifications of the Mack-Wolfe umbrella tests for a generalized Behrens-Fisher problem

We are concerned with testing procedures for umbrella alternatives in the k-sample location problem without making the assumption that the underlying populations have the same shape. Modifications of the Mack-Wolfe tests are proposed for the cases when the peak of the umbrella is known or unknown. The proposed procedures are exactly distribution-free when the continuous populations have the same shape. The modified test for peak-known umbrella alternatives remains asymptotically distribution-free when the continuous populations are symmetric, but not necessarily with the same shape.     

Al_（0．3）Ga_（0．7）As／GaAs超晶格在高能高温注入下的晶格损伤

用卢瑟福背散射／沟道技术研究了ＩＭｅＶＳｉ￣＋衬底加温注入Ａｌ_（０．３）Ｇａ_（０．７）Ａｓ／ＧａＡｓ超晶格和作为比较的ＧａＡｓ晶体后晶格的损伤积累与注入剂量的关系。实验结果表明，在注入剂量比较小的情况下，两种晶体都只有很轻微的损伤；动态退火过程的存在抑制了晶格损伤的积累。但在较高的注入剂量下，在几乎无损伤的表面下两种晶体中都形成了损伤埋层，且ＧａＡｓ中损伤峰处的损伤程度和损伤峰的宽度都大于Ａｌ_（０．３）Ｇａ_（０．７）Ａｓ／ＧａＡｓ超晶格中的情形，根据级联碰撞理论分析了晶体中的损伤积累过程，并从化学键相对强度差异的角度定性地解释了ＧａＡｓ和Ａｌ_（０．３）Ｇａ_（０．７）Ａｓ／ＧａＡｓ超晶格实验结果的不同。