A note on the security of PAP

In this letter, we analyze the security of an RFID authentication protocol proposed by Liu and Bailey [1], called privacy and authentication protocol (PAP). We present two traceability attacks and an impersonation attack.     

危机与契机并存——从学位论文看我国建筑更新领域学术研究发展情况

本文对我国近十余年间建筑更新及建筑保护领域学术论文做了全面的搜集和多角度的统计工作,分析介绍了我国建筑更新领域的学术地位和学术发展特征,并对其存在的问题进行了阐述和深层次剖析,力求为我国建筑更新领域后续研究工作的开展起到参考借鉴作用。     

Mass transfer during osmotic dehydration of pineapple rings

The effect of temperature (30, 40 and 50°C) and sucrose concentration (50, 60 and 70°Brix) on the osmotic dehydration of commercial size pineapple rings were studied, at an initial ratio of 1:4 fruit:sucrose solution. The rate of water loss in the fruit varied with both osmotic solution concentration and temperature. A proposed model based on Crank's equation was fitted to the experimental data.     

Hydrocarbon preservation and formation water geochemistry in abnormal pressure system in the Bawu area of Lishu depression,Songliao Basin,China

The hydrocarbon production in the Bawu area of Lishu Depression is high. However, the Bawu area has undergone three main tectonic movements, the strata were strongly uplifted and eroded, and the fractures were extremely developed. The conditions of hydrocarbon preservation have become intricate. In this study, by analyzing isotopes compositions and geochemical features of formation water, and the characteristics of formation pressure, the hydrocarbon preservation can be deduced. The subnormal and lower normal pressure zones (away from Xiaokuan Fault) of Yingcheng and Shahezi Formations are relatively closed and more conducive to hydrocarbon preservation.     

改进的中值滤波算法

针对中值滤波器降低图像分辨率的缺点,提出一种改进的中值滤波算法,即在中值滤波前进行边缘判断.首先判断象素是否是边缘,是则不进行变换,直接将该像素值输出.反之则进行中值滤波,将中值滤波后的值输出.实验表明,该算法对图像进行中值滤波时保存了图像的边缘细节.     

JPEG encryption for image rescaling in the encrypted domain

This work proposes a novel protocol of encrypting the JPEG image suitable for image rescaling in the encrypted domain. To protect the privacy of original content, the image owner perturbs the texture and randomizes the structure of the JPEG image by enciphering the quantized Discrete Cosine Transform (DCT) coefficients. After receiving the encrypted JPEG image, the service provider generates a rescaled JPEG image by down-sampling the encrypted DCT coefficients. On the recipient side, the encrypted JPEG image rescaled by the service provider can be decrypted to a plaintext image with a lower resolution with the aid of encryption keys. Experimental results show that the proposed method has a good capability of rescaling the privacy-protected JPEG file.     

低温保存对超干烟草种子活力的影响

将在低温条件下保存的超干烟草种子的活力与在原干燥器内和常温常湿（自然条件）下继续保存的种子进行比较,结果表明超干燥的烟草种子最适合在４℃下继续保存,其次是在－８℃低温下保存,再其次是在干燥器内继续保存,最不利于在常温常湿下继续保存。由此说明超干烟草种子可以安全地向低温冷藏库转移,而且其种子寿命长于继续进行超干燥保存的种子,而经过超干燥处理后的烟草种子不宜在自然条件下保存。     

Potential pitfalls of smart city development: A study on parking mobile applications (apps) in Hong Kong

Smart cities are built upon information and communication technologies (ICTs) to enable a broad range of advanced services. Through a comprehensive literature review, this study identified four pitfalls brought by the pervasive application of ICT, including information insecurity, privacy leakage, information islands, and digital divide. Therefore, a questionnaire survey together with 27 interviews was conducted in Hong Kong to investigate how the public perceived these pitfalls within the context of mobile apps providing real-time parking information which form a major part of smart mobility. System insecurity and privacy leakage were found to arouse worries among the app-users while their awareness of protecting personal data was found to have room for improvement. Islands of real-time parking information occur as a result of the lack of collaboration among private carpark operators. Digital divide existed widely among the disadvantaged groups and the problem cannot be solved by mere provision of ICT facilities. Overall, technologies alone cannot make a city smart or smarter. It is the suitable way in which ICTs are used to serve all citizens that matters.     

冬枣的保鲜方法进展和发展趋势

介绍了冬枣的采收时期和采收的方法,冬枣贮藏保鲜技术和国际上的保鲜发展趋势.