Maximum Hit Rate Research Articles

The application of social recommendation algorithm integrating attention model in movie recommendation

To improve the accuracy of recommendations, alleviate sparse data problems, and mitigate the homogenization of traditional socialized recommendations, a gated recurrent neural network is studied to construct a relevant user preference model to mine user project preferences. Through the Preference Attention Model Based on Social Relations (PASR), this study extracts user social influence preferences, performs preference fusion, and obtains a Recommendation Algorithm Based on User Preference and Social Influence (UPSI). The study demonstrates that the UPSI algorithm outperforms other methods like the SocialMF algorithm, yielding improved recommendation results, higher HR values, and larger NDCG values. Notably, when the K value equals 25 in Top-K recommendation and using the CiaoDVDs dataset, the NDCG value of the UPSI algorithm is 0.267, which is 0.120 higher than the SocialMF algorithm's score. Considering the user's interaction with the project and their social relationships can enhance the effectiveness of recommendations. Unlike other variants, the UPSI algorithm achieves a maximum hit rate HR value of 0.3713 and NDCG value of 0.2108 in the Douban dataset. In the CiaoDVDs dataset, the maximum hit rate HR value of UPSI is 0.4856, 0.0333 higher than UPS-A, 0.0601 higher than UPS, and 0.0901 higher than UP. Research methods can effectively improve the homogenization problem of traditional socialized recommendations, increase algorithm hit rates and NDCG values. Compared to previous studies, research methods can more fully explore the preference correlation between users, making recommended movies more in line with user requirements.

An Improved Web Caching System With Locally Normalized User Intervals

Caching is one of the most promising areas in the field of future internet architecture like Information-centric Networking, Software Defined Networking, and IoT. In Web caching, most of the web content is readily available across the network, even if the webserver is not reachable. Several existing traditional caching methods and cache replacement strategies are evaluated based on the metrics like hit ratio and byte hit Ratio. However, these metrics have not been improved over the period because of the traditional caching policies. So, in this paper, we have used an intelligent function like locally normalized intervals of page visit, website duration, users’ interest between user groups is proposed. These intervals are combined with multiple distance metrics like Manhattan, squared Euclidean, and 3-,4-,5-norm Minkowski. In order to obtain significant common user navigation patterns, the clustering relation between the users using different intervals and distances is thoroughly analyzed. These patterns are successfully coupled with greedy web cache replacement strategies to improve the efficiency of the proposed web cache system. Particularly for improving the caching metrics more, we used an AI-based intelligent approach like Random Forest classifier to boost the prefetch buffer performance and achieves the maximum hit rate of 0.89, 0.90, and byte hit rate of 0.87, 0.89 for Greedy Dual Size Frequency and Weighted Greedy Dual Size Frequency algorithms, respectively. Our experiments show good hit/byte hit rates than the frequently used algorithms like least recently used and least frequently used.

Realisation of Cache Optimisation using New Technique

An impressive design of cache memory is an important view in computer architecture to boost or increase the system performance. In this task we study the response of reducing the cache performance to the cache address on the performance experimentally. Since cache miss penalty has direct contact on the system’s performance. To overtake from this, we proposed a new model in which we use revisited second chance FIFO (RS FIFO), which uses partial comparator and use multiple search to increase cache hit rate, by reducing cache miss rate. The Above proposed technique gives maximum hit rate when using revisited SFIFO rather than FIFO. Keywords: cache mapping technique; hit rate; miss rate; cache optimisation; cache replacement policies.

Mechanical Properties and Acoustic Emission Properties of Rocks with Different Transverse Scales

Since the stability of engineering rock masses has important practical significance to projects like mining, tunneling, and petroleum engineering, it is necessary to study mechanical properties and stability prediction methods for rocks, cementing materials that are composed of minerals in all shapes and sizes. Rocks will generate acoustic emission during damage failure processes, which is deemed as an effective means of monitoring the stability of coal rocks. In the meantime, actual mining and roadway surrounding rocks tend to have transverse effects; namely, the transverse scale is larger than the length scale. Therefore, it is important to explore mechanical properties and acoustic emission properties of rocks under transverse size effects. Considering the transverse scale effects of rocks, this paper employs the microparticle flow software PFC2D to explore the influence of different aspect ratios on damage mechanics and acoustic emission properties of rocks. The results show that (1) the transverse scale affects uniaxial compression strength of rocks. As the aspect ratio increases, uniaxial compression strength of rocks decreases initially and later increases, showing a V-shape structure and (2) although it affects the maximum hit rate and the strain range of acoustic emission, it has little influence on the period of occurrence. As the transverse scale increases, both damage degree and damage rate of rocks decrease initially and later increase.

A 4.2 ps Time-Interval RMS Resolution Time-to-Digital Converter Using a Bin Decimation Method in an UltraScale FPGA

The common solution for a field programmable gate array (FPGA)-based time-to-digital converter (TDC) is constructing a tapped delay line (TDL) for time interpolation to yield a sub-clock time resolution. The granularity and uniformity of the delay elements of TDL determine the TDC time resolution. In this paper, we propose a dual-sampling TDL architecture and a bin decimation method that could make the delay elements as small and uniform as possible, so that the implemented TDCs can achieve a high time resolution beyond the intrinsic cell delay. Two identical full hardware-based TDCs were implemented in a Xilinx UltraScale FPGA for performance evaluation. For fixed time intervals in the range from 0 to 440 ns, the average time-interval RMS resolution is measured by the two TDCs with 4.2 ps, thus the timestamp resolution of single TDC is derived as 2.97 ps. The maximum hit rate of the TDC is as high as half the system clock rate of FPGA, namely 250 MHz in our demo prototype. Because the conventional online bin-by-bin calibration is not needed, the implementation of the proposed TDC is straightforward and relatively resource-saving.

An Efficient Variable Selection Method for Predictive Discriminant Analysis

Seeking a subset of relevant predictor variables for use in predictive model construction in order to simplify the model, obtain shorter training time, as well as enhance generalization by reducing overfitting is a common preprocessing step prior to training a predictive model. In predictive discriminant analysis, the use of classic variable selection methods as a preprocessing step, may lead to “good” overall correct classification within the confusion matrix. However, in most cases, the obtained best subset of predictor variables are not superior (both in terms of the number and combination of the predictor variables, as well as the hit rate obtained when used as training sample) to all other subsets from the same historical sample. Hence the obtained maximum hit rate of the obtained predictive discriminant function is often not optimal even for the training sample that gave birth to it. This paper proposes an efficient variable selection method for obtaining a subset of predictors that will be superior to all other subsets from the same historical sample. In application to real life datasets, the obtained predictive function using our proposed method achieved an actual hit rate that was essentially equal to that of the all-possible-subset method, with a significantly less computational expense.

Web Cache Replacement with the Repairable LRU Algorithm

The number of people using the web objects has enlarged quickly. This situation effects the traffic network. At present, the web cache memory is used to solve the traffic network problem. It can keep web objects from original servers and clients can download web objects from the web cache memory. However, the web cache memory has a small memory therefore it cannot record every web object. Many techniques are used to solve this problem but these techniques give the average hit rate of not over 40 percent. Therefore, this research investigates the optimization with mathematical and statistical methods for increasing the hit rate with web cache memory which are as follows: estimated value, interpolation, cubic spline, to find area under the curve function and first order condition. This research investigates to create the Repairable Least Recently Used (RLRU) algorithm to recommend for the web cache memory management. This algorithm is tested with the datasets obtained from a university in Thailand. Furthermore, the RLRU algorithm has compared the performance of the hit rate with the LRU algorithm. The experimental results of this research can apprize that the RLRU algorithm gives the maximum hit rate at 72.56 percent while the LRU algorithm offers the maximum hit rate at 53.34 percent. However, the average hit ratio of the RLRU algorithm is at 53.80 percent while the average hit ratio of the LRU algorithm amounts to about 12.99 percent.

Timepix3: first measurements and characterization of a hybrid-pixel detector working in event driven mode

Timepix3 is a hybrid pixel detector readout chip. It features a data driven readout mode where the chip sends out a data packet containing pixel coordinate, time over threshold and time of arrival immediately after the hit is processed by the pixel. The maximum hit rate is 40 Mhits/cm2/s with a minimum time step in the arrival time measurement of 1.56 ns. The pixel matrix consist of 256 × 256 square pixels at a 55 μm pitch and the pixel front end noise is 61 e− RMS. In this paper we present the first radiation measurements with Timepix3 bump bonded to a 300 μm thick silicon sensor. The chip is calibrated per pixel, using internal test pulses and the calibration is verified using X-ray fluorescence. The energy resolution, threshold dispersion and gain dispersion is measured. The energy resolution in time over threshold mode under normal operation conditions is 4.07 keV FWHM at 59.5 keV. At 10.5 keV an energy resolution of 0.72 keV FWHM was achieved in photon counting mode and in time over threshold mode, by optimizing the energy response, we achieved a 1.38 keV FWHM. We also investigate the time walk and present first results on using the time information for track reconstruction.

A spatial approach of magnitude-squared coherence applied to selective attention detection

Auditory selective attention is the human ability of actively focusing in a certain sound stimulus while avoiding all other ones. This ability can be used, for example, in behavioral studies and brain-machine interface. In this work we developed an objective method - called Spatial Coherence - to detect the side where a subject is focusing attention to. This method takes into consideration the Magnitude Squared Coherence and the topographic distribution of responses among electroencephalogram electrodes. The individuals were stimulated with amplitude-modulated tones binaurally and were oriented to focus attention to only one of the stimuli. The results indicate a contralateral modulation of ASSR in the attention condition and are in agreement with prior studies. Furthermore, the best combination of electrodes led to a hit rate of 82% for 5.03 commands per minute. Using a similar paradigm, in a recent work, a maximum hit rate of 84.33% was achieved, but with a greater a classification time (20s, i.e. 3 commands per minute). It seems that Spatial Coherence is a useful technique for detecting focus of auditory selective attention.

Monte Carlo study for optimal conditions in single-shot imaging with femtosecond x-ray laser pulses

Intense x-ray pulses from x-ray free electron lasers (XFELs) enable the unveiling of atomic structure in material and biological specimens via ultrafast single-shot exposures. As the radiation is intense enough to destroy the sample, a new sample must be provided for each x-ray pulse. These single-particle delivery schemes require careful optimization, though systematic study to find such optimal conditions is still lacking. We have investigated two major single-particle delivery methods: particle injection as flying objects and membrane-mount as fixed targets. The optimal experimental parameters were searched for via Monte Carlo simulations to discover that the maximum single-particle hit rate achievable is close to 40%.

Model-based automated detection of echolocation calls using the link detector

The link detector combines a model-based spectral peak tracker with an echo filter to detect echolocation calls of bats. By processing calls in the spectrogram domain, the links detector separates calls that overlap in time, including call harmonics and echoes. The links detector was validated by using an artificial recording environment, including synthetic calls, atmospheric absorption, and echoes, which provided control of signal-to-noise ratio and an absolute ground truth. Maximum hit rate (2% false positive rate) for the links detector was 87% compared to 1.5% for a spectral peak detector. The difference in performance was due to the ability of the links detector to filter out echoes. Detection range varied across species from 13 to more than 20 m due to call bandwidth and frequency range. Global features of calls detected by the links detector were compared to those of synthetic calls. The error in all estimates increased as the range increased, and estimates of minimum frequency and frequency of most energy were more accurate compared to maximum frequency. The links detector combines local and global features to automatically detect calls within the machine learning paradigm and detects overlapping calls and call harmonics in a unified framework.

Implementation of the ASDBLR straw tube readout ASIC in DMILL technology

The ASDBLR application-specific integrated circuit (ASIC) provides eight channels of low-noise low-power high-rate on-detector readout suitable for the ATLAS transition radiation tracker (TRT) at the large hadron collider. The TRT's unprecedented wire chamber readout requirements of a maximum hit rate per wire of 20 MHz and double-pulse resolution of /spl sim/25 ns with position resolution of better than 150 /spl mu/m in a high radiation environment have been addressed in the design of the ASDBLR. A carefully tuned ion tail cancellation stage followed by an output sensing baseline restorer implemented in differential structures provides robust signal-processing combination compatible with the realities of ASIC design. Two comparators track the output of the signal-processing stage to provide tracking information from charged particles and evidence of higher energy transition radiation photons; their outputs are summed as current steps to form a differential ternary output. The ten-year total dose requirement for neutrons of 10/sup 14/ n/cm/sup 2/ and 1.5 MRad of ionizing radiation led to the implementation of this design in the radiation hardened DMILL process.

Studies on ageing effects and rate dependence of Thin Gap Chambers

We studied ageing effects of Thin Gap Chambers (TGC). The gas mixture was 55% of CO2 and 45% of n-pentane. The TGCs were irradiated with β-rays of a 90Sr source. The maximum hit rate per wire was 41–84kHz/cm. The gas flow rate was equivalent to replacing 0.3–2.6 of the TGC volume per minute. We observed neither significant deterioration on pulse height nor time jitter up to an accumulated charge of 1C/cm. We also performed a beam test to study the TGC performance under a high radiation environment. The maximum background rate of approximately 3.8MHz/cm2 was achieved using a 90Sr source. The pulse height did not change significantly up to background rates of 100kHz/cm2.

A 2D smart pixel detector for time-resolved crystallography

A smart pixel detector is being developed for time-resolved crystallography for biological and material science applications. Using the pixel detector presented here, the Laue method will enable the study of the evolution of structural changes that occur within a protein as a function of time. The x-ray pixellated detector is assembled to the integrated circuit through a bump bonding process. Within a pixel size of 150×150 mm2, a low-noise preamplifier-shaper, a discriminator, a 3-bit counter and the readout logic are integrated. The readout, based on the column architecture principle, will accept hit rates above 5×108/cm2/s with a maximum hit rate per pixel of 1 MHz. This detector will allow time-resolved Laue crystallography to be performed in a frameless operation mode, without dead time. Target specifications, architecture, and preliminary results on a 8×8 prototype are presented.

A 2D smart pixel detector for time resolved protein crystallography

A smart pixel detector is being developed for Time Resolved Crystallography for biological and material science applications. Using the Pixel Detector presented here, the Laue method will enable the study of the evolution of structural changes that occur within the protein as a function of time. The X-ray pixellated detector is assembled to the integrated circuit through a bump bonding process. Within a pixel size of 150/spl times/150 /spl mu/m/sup 2/, a low noise preamplifier-shaper, a discriminator, a 3 bit counter and the readout logic are integrated. The read out, based on the Column Architecture principle, will accept hit rates above 5/spl times/10/sup 8//cm/sup 2//s with a maximum hit rate per pixel of 1 MHz. This detector will allow time resolved Laue crystallography to be performed in a frameless operation mode, without dead time. Target specifications, architecture and preliminary results on the 8/spl times/8 front-end prototype and the column readout are presented.

２項事象系列の出現確率判断における確率認知

The fallacious probability judgment of binary event sequence (Bernoulli sequence) was studied in terms of probability cognition. The categorizational fallacy hypothesis (Kasai, 1982) asserts that people tend to respond with a categorical probability (the probability of occurrence of the category to which a given instance belongs) even when they are asked to answer the individual probability of instance. In Exp. 1, 46 undergraduates were instructed to make the paired comparison of probability among 15 binary sequences of length 6. Their modal judgments were compared with the theoretical predictions based on the ideal probability distributions and also with the predictions from the subjective distributions which were generated by 24 undergraduates in Exp. 2. The results confirmed the predictions, particularly those based on the subjective distributions (maximum hit rate 82.9%). Based on these results it was concluded that the subjects judged the likelihood of each sequence in terms of categorical probability rather than the required individual probability, and it was suggested that the fallacious judgment is derived from the cognitive process of abstracting and symbolizing.