影响建陶产品生命周期因素的分析与探讨

本文从建陶产品生命周期缩短的现象入手，应用产品生命周期理论和相关的数学模型，对建陶产品生命周期的各个影响因素进行了分析和探讨。     

A parallel image encryption method based on compressive sensing

Recently, compressive sensing-based encryption methods which combine sampling, compression and encryption together have been proposed. However, since the quantized measurement data obtained from linear dimension reduction projection directly serve as the encrypted image, the existing compressive sensing-based encryption methods fail to resist against the chosen-plaintext attack. To enhance the security, a block cipher structure consisting of scrambling, mixing, S-box and chaotic lattice XOR is designed to further encrypt the quantized measurement data. In particular, the proposed method works efficiently in the parallel computing environment. Moreover, a communication unit exchanges data among the multiple processors without collision. This collision-free property is equivalent to optimal diffusion. The experimental results demonstrate that the proposed encryption method not only achieves the remarkable confusion, diffusion and sensitivity but also outperforms the existing parallel image encryption methods with respect to the compressibility and the encryption speed.     

A noisy-smoothing relevance feedback method for content-based medical image retrieval

In this paper, we address a new problem of noisy images which present in the procedure of relevance feedback for medical image retrieval. We concentrate on the noisy images, caused by the users mislabeling some irrelevant images as relevant ones, and a noisy-smoothing relevance feedback (NS-RF) method is proposed. In NS-RF, a two-step strategy is proposed to handle the noisy images. In step 1, a noisy elimination algorithm is adopted to identify and eliminate the noisy images. In step 2, to further alleviate the influence of noisy images, a fuzzy membership function is employed to estimate the relevance probabilities of retained relevant images. After noisy handling, the fuzzy support vector machine, which can take into account different relevant images with different relevance probabilities, is adopted to re-rank the images. The experimental results on the IRMA medical image collection demonstrate that the proposed method can deal with the noisy images effectively.     

A DNA-based data hiding technique with low modification rates

In 2010, Shiu et al. proposed three DNA-based reversible data hiding schemes with high embedding capacity. However, their schemes were not focused on DNA modification rate or the expansion problem. Therefore, we propose a novel reversible data hiding scheme based on histogram technique to solve the weaknesses of Shiu et al.’s schemes. The proposed scheme transforms the DNA sequence into a binary string and then combines several bits into a decimal integer. These decimal integers are used to generate a histogram. Afterwards, the proposed scheme uses a histogram technique to embed secret data. The experimental results show that the modification rate of our proposed scheme is 69 % lower than that of Shiu et al.’s schemes for the same embedding capacity. In addition, the length of the DNA sequence remains unchanged in the proposed scheme.     

Detecting video frame-rate up-conversion based on periodic properties of inter-frame similarity

Video frame-rate up-conversion is one of the common operations for tampering digital videos in the temporal domain, such as creating fake high-quality videos and splicing two video clips with different frame rates. However, few existing works have been proposed for detecting this form of tampering operation. Based on the analysis of extensive experiments, we found that frame-rate up-conversion algorithms employed in most current video editing softwares will inevitably introduce some periodic artifacts into inter-frame similarity in the resulting video frame sequence. By analyzing such artifacts, we propose a simple yet very effective method to expose video after frame-rate up-conversion, and further estimate its original frame rate. The experimental results evaluated on 100 original videos at different frame rates have shown the effectiveness of the proposed method. The average detection accuracy can achieve as high as 99 % on noise-free videos in uncompressed and H.264/AVC formats. Besides, the proposed method is robust to noise as the detection accuracy could reach over 85 % and 95 % on noised videos with Gaussian white noise when SNR is 33 db and 36 db respectively.     

Online mining abnormal period patterns from multiple medical sensor data streams

With the advanced technology of medical devices and sensors, an abundance of medical data streams are available. However, data analysis techniques are very limited, especially for processing massive multiple physiological streams that may only be understood by medical experts. The state-of-the-art techniques only allow multiple medical devices to independently monitor different physiological parameters for the patient’s status, thus they signal too many false alarms, creating unnecessary noise, especially in the Intensive Care Unit (ICU). An effective solution which has been recently studied is to integrate information from multiple physiologic parameters to reduce alarms. But it is a challenge to detect abnormalities from high frequently changed physiological streams data, since abnormalities occur gradually due to the complex situation of patients. An analysis of ICU physiological data streams shows that many vital physiological parameters are changed periodically (such as heart rate, arterial pressure, and respiratory impedance) and thus abnormalities are generally abnormal period patterns. In this paper, we develop a Mining Abnormal Period Patterns from Multiple Physiological Streams (MAPPMPS) method to detect and rank abnormalities in medical sensor streams. The efficiency and effectiveness of the MAPPMPS method is demonstrated by a real-world massive database of multiple physiological streams sampled in ICU, comprising 250 patients’ streams (each stream involving over 1.3 million data points) with a total size of 28 GB data.     

高支模施工安全管理问题与对策

高支模工程安全管理不仅需要很高的技术,而且安全管理本身也具有较大的随机性,这就导致相关人员在开展安全管理工作时具有一定的难度。面对这一问题,相关监理人员必须从施工方案的审批、应急预案的落实、质量安全作业的施工技术交底和施工过程中所需要的各种原材料进场前的检验等方面加强管理。     

变电运行倒闸操作的危险点及预防对策探究

在实际操作中,由于变电运行非常复杂,很容易出现危险,因此,做好相关危险点的分析和预防工作,对保证电力系统运行安全有着非常重要的意义。结合变电运行倒闸操作中的危险点,对其预防对策进行了分析和探讨。     

浅谈煤矿地质构造评价指标系统的建立与优选

煤炭资源是我国社会发展的重要能源之一,在煤炭资源开采过程中,必须对煤矿的地质结构进行认真分析。重点分析了煤矿地质结构与煤矿开采的关系,通过对煤矿地质结构的发展规律进行分析,建立了一套完善的煤矿地质构造评价指标系统,从而为煤矿资源的安全开采提供了保障。     

高职院校工学结合人才培养机制的创新与实践

为了推进工学结合、校企合作的人才培养模式改革,以创建国家示范性高职院校为实践平台,通过创新机制,在一定程度上解决了制约工学结合人才培养模式改革的主要问题。