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Korotkoff sounds are known to change their characteristics during blood pressure (BP) measurement, resulting in some uncertainties for systolic and diastolic pressure (SBP and DBP) determinations. The aim of this study was to assess the variation of Korotkoff sounds during BP measurement by examining all stethoscope sounds associated with each heartbeat from above systole to below diastole during linear cuff deflation. Three repeat BP measurements were taken from 140 healthy subjects (age 21 to 73 years; 62 female and 78 male) by a trained observer, giving 420 measurements. During the BP measurements, the cuff pressure and stethoscope signals were simultaneously recorded digitally to a computer for subsequent analysis. Heart beats were identified from the oscillometric cuff pressure pulses. The presence of each beat was used to create a time window (1s, 2000 samples) centered on the oscillometric pulse peak for extracting beat-by-beat stethoscope sounds. A time-frequency two-dimensional matrix was obtained for the stethoscope sounds associated with each beat, and all beats between the manually determined SBPs and DBPs were labeled as ‘Korotkoff’. A convolutional neural network was then used to analyze consistency in sound patterns that were associated with Korotkoff sounds. A 10-fold cross-validation strategy was applied to the stethoscope sounds from all 140 subjects, with the data from ten groups of 14 subjects being analysed separately, allowing consistency to be evaluated between groups. Next, within-subject variation of the Korotkoff sounds analysed from the three repeats was quantified, separately for each stethoscope sound beat. There was consistency between folds with no significant differences between groups of 14 subjects (P = 0.09 to P = 0.62). Our results showed that 80.7% beats at SBP and 69.5% at DBP were analysed as Korotkoff sounds, with significant differences between adjacent beats at systole (13.1%, P = 0.001) and diastole (17.4%, P < 0.001). Results reached stability for SBP (97.8%, at 6th beats below SBP) and DBP (98.1%, at 6th beat above DBP) with no significant differences between adjacent beats (SBP P = 0.74; DBP P = 0.88). There were no significant differences at high cuff pressures, but at low pressures close to diastole there was a small difference (3.3%, P = 0.02). In addition, greater within subject variability was observed at SBP (21.4%) and DBP (28.9%), with a significant difference between both (P < 0.02). In conclusion, this study has demonstrated that Korotkoff sounds can be consistently identified during the period below SBP and above DBP, but that at systole and diastole there can be substantial variations that are associated with high variation in the three repeat measurements in each subject.

Tinnitus is a phantom auditory perception. An increasing number of people begin to complain that tinnitus bring a lot of negative things to their lives. Tinnitus retraining therapy (TRT) has been used for many years in tinnitus clinics around the world. Two components that are essential for TRT are counselling and sound therapy. Scientific researches show that TRT can relieve tinnitus by some similar and not repetitive music. It is important for us to design such music. We aimed to synthesize music based on chaos theory and musical instrument digital interface (MIDI) files. However, if we only directly map the output of chaotic systems to pitch or rhythm value, there will be some imperfections that we cannot overcome at the same time. So we proposed a new method of synthesizing music for tinnitus therapy. Experiment results show that the music in this paper was not only self-similar, but also no sudden changes. What's more, the fluctuation of pitch and duration obey 1/f power law. In a word, it can promote recent advances in tinnitus treatment.

As the incidence of tinnitus increasing year by year, more and more people begin to pay attention to the exploration and research of tinnitus treatment. Because of its advantages such as validity and security, masking treatment has become a common method of treating tinnitus. The only way for patients to get treatment is going to hospitals. However, it is costly and not conducive for patients to treat themselves anywhere. Aiming at Android handsets, we built a practical mobile treatment platform for tinnitus which was easy for development. With the help of multiple network technologies, the platform accomplished several functions such as the acquisition of the tinnitus therapy sound and personal information from the server, the doctor-patient communication and the tinnitus forum. The result shows that the platform is stable and can realize various functions smoothly. It provides a new idea for tinnitus protable treatment and has an excellent prospect.

Photoplethysmography (PPG) signal has been commonly used in detecting the peripheral blood volume pulse. This kind of optical-based technique is simple, rapid, low-cost and non-invasive. It can be used widely for different purposes. Many useful information can be obtained from the PPG signal, including heart rate, respiratory rate, pulse wave velocity (PWV) and so on. In order to obtain these information, feature points must be extracted first. In this paper eight healthy subjects were studied. One PPG probe was used to record the PPG signal from left ear and the ECG signal has also been recorded simultaneously. These signals were converted into digital signals and stored into computer for off-line analysis. An automatic algorithm based on wavelet approach has been developed to extract feature points from the PPG signal, then compare with the manual measurement. The result shows that the automatic algorithm provided an effective way for PPG signal feature extraction.

To curb worm spread, it is vital to detect worms in time and restrict the victims' network behavior effectively. A worm detection and containment system for local networks is proposed. Normal service requests are characterized with the self-set, which is applied to monitor for suspicious service requests. The system correlates the suspicious service requests in the form of binary trees, and binary trees' anomaly values are monitored for worm attacks. Possible worm victims are determined from the binary trees. Based on the self-set, the worm victims' normal traffic is permitted while their worm activities are strictly contained. Experiments show the system contains worms effectively, and the detrimental effect of the system's deployment on normal network traffic is negligible.

Fuzzing has proved successful in finding security vulnerabilities in large binary programs. Traditionally, reversing engineering technologies are used to locate codes that may lead to exceptions in Fuzzing, and this may demand a great amount of human efforts and consequently gives rise to low efficiency. In this paper, an automatic fault localization method for Fuzzing is proposed together with an automatic vulnerability analysis system named Fuzz Loc. Fuzz Loc can filter key instructions that may directly cause exceptions. Starting from these key instructions, Fuzz Loc implements automatic fault localization by back tracing. With Fuzz Loc, a great deal of human efforts can be saved. Experiments show that Fuzz Loc can locate fault codes accurately with little human intervention and consequently improves efficiency of fault analysis and vulnerability mining.

Line-loss management is a complex and systematic project. This paper analyses the feature of scientific quality management system, which is systematic, standardized, scientific, and operable, sustainable and comprehensive. Combined with the practice of the line-loss management, this paper proposes the establishment of a scientific management system in line with the characteristics of line-loss management mode which must be ldquosix in placerdquo, that is, organizations in place, systems in place, responsibility in place, and assessment in place, management in place and measures in place. On this basis, the paper also focuses on the development of line-loss management in the future.