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关键词： Women in computing   intersectionality   computing demographics   computing history   historical context analysis   race   ethnicity   gender   diversity  

摘要： Although computing occupations have some of the greatest projected growth rates, there remains a deficit of graduates in these fields. The struggle to engage enough students to meet demands is particularly pronounced for groups already underrepresented in computing. specifically, individuals that self-identify as a woman, or as Black, Hispanic/Latinx, or Native American. Prior studies have begun to examine issues surrounding engagement and retention, but more understanding is needed to close the gap, and to broaden participation. In this research, we provide quantitative evidence from the Multiple-Institution Database for Investigating Engineering Longitudinal Development-a longitudinal, multi-institutional database to describe participation trends of marginalized groups in computer science. Using descriptive statistics, we present the enrollment and graduation rates for those situated at the intersection of race/ethnicity and gender between 1987 and 2018. In this work, we observed periods of significant flux for Black men and women. and White women in particular, and consistently low participation of Hispanic/Latinx and Native American men and women, and Asian women. To provide framing for the evident peaks and valleys in participation, we applied historical context analysis to describe the political, economic, and social factors and events that may have impacted each group. These results put a spotlight on populations largely overlooked in statistical work and have the potential to inform educators, administrators, and researchers about how enrollments and graduation rates have changed over time in computing fields. In addition, they offer insight into potential causes for the vicissitudes, to encourage more equal access for all students going forward.

关键词： Social networking (online)   Optimal control   Diffusion processes   Dynamic scheduling   Resource management   Computer science   Biological system modeling   Fraud information diffusion   mobile social networks (MSNs)   optimal control   simulation   system dynamics  

摘要： Mobile social networks (MSNs) provide real-time information services to individuals in social communities through mobile devices. However, due to their high openness and autonomy, MSNs have been suffering from rampant rumors, fraudulent activities, and other types of misuses. To mitigate such threats, it is urgent to control the spread of fraud information. The research challenge is: how to design control strategies to efficiently utilize limited resources and meanwhile minimize individuals' losses caused by fraud information? To this end, we model the fraud information control issue as an optimal control problem, in which the control resources consumption for implementing control strategies and the losses of individuals are jointly taken as a constraint called total cost, and the minimum total cost becomes the objective function. Based on the optimal control theory, we devise the optimal dynamic allocation of control strategies. Besides, a dynamics model for fraud information diffusion is established by considering the uncertain mental state of individuals, we investigate the trend of fraud information diffusion and the stability of the dynamics model. Our simulation study shows that the proposed optimal control strategies can effectively inhibit the diffusion of fraud information while incurring the smallest total cost. Compared with other control strategies, the control effect of the proposed optimal control strategies is about 10% higher.

关键词： Feature extraction   Gray-scale   Image color analysis   Learning systems   Neural networks   Training   Computer science   Colorization   global broad learning system (GBLS)   global features   local broad learning system (LBLS)   local features  

摘要： The scribble- and example-based colorization methods have fastidious requirements for users, and the training process of deep neural networks for colorization is quite time-consuming. We instead proposed an automatic colorization approach with no dependence on user input and no need to endure long training time, which combines local features and global features of the input gray-scale images. Low-, mid-, and high-level features are united as local features representing cues existed in the gray-scale image. The global feature is regarded as data prior to guiding the colorization process. The local broad learning system is trained for getting the chrominance value of each pixel from the local features, which could be expressed as a chrominance map according to the position of pixels. Then, the global broad learning system is trained to refine the chrominance map. There are no requirements for users in our approach, and the training time of our framework is an order of magnitude faster than the traditional methods based on deep neural networks. To increase the user's subjective initiative, our system allows users to increase training data without retraining the system. Substantial experimental results have shown that our approach outperforms state-of-the-art methods.

关键词： Math. Appl. in Environmental Science   Earth Sciences   general   Probability Theory and Stochastic Processes   Statistics for Engineering   Physics   Computer Science   Chemistry and Earth Sciences   Computational Intelligence   Waste Water Technology / Water Pollution Control / Water Management / Aquatic Pollution  

摘要： Constructing an accurate and dependable displacement forecasting model is a prerequisite for realizing effective early warning systems of landslide disasters. To overcome the drawbacks of previous displacement prediction models for landslides with step-like deformation characteristics, such as the low prediction accuracy of the mutational displacements and the unclear reliability of the prediction results, we propose a novel hybrid interval forecasting model. This model consists of four parts. First, clustering by fast search and find of density peaks is implemented to distinguish the deformation states of the landslide. Second, the ensemble classifier based on the random forest algorithm is established to identify the deformation states. Third, based on the wild bootstrap, kernel extreme learning machine, and back propagation neural network approaches, the ensemble regressors under different deformation states are built. Finally, by combining the ensemble classifier and ensemble regressors, an interval prediction framework is constructed to realize the dynamic interval prediction of landslide displacement. Taking the Baishuihe landslide as an example, the datasets of three monitoring sites from June 2006 to December 2016 are used to verify the accuracy and reliability of the proposed model. The results show that the proposed model can effectively improve the prediction accuracy of mutational displacements, with the root mean square errors of 28.19 mm, 14.21 mm, and 34.44 mm and the R-squares of 0.9827, 0.9955, and 0.9903, respectively. Moreover, the reliability of the prediction results obtained using this model can be expressed in the flexible prediction intervals (PIs) under different deformation states. The coverage width-based criteria of PIs at 90% nominal confidence are 140.38 mm, 86.61 mm, and 173.68 mm, respectively. In conclusion, the proposed model provides a good basis for developing early warning systems for landslides with step-like deformation charact

关键词： Machinery  

摘要： To reversify an arbitrary sequential algorithm A, we gently instrument A with bookkeeping machinery. The result is a step-for-step reversible algorithm that mimics A step-for-step and stops exactly when A does. Without loss of generality, we presume that algorithm A is presented as an abstract state machine that is behaviorally identical to A. The existence of such representation has been proven theoretically, and the practicality of such representation has been amply demonstrated. © 2021, European Association for Theoretical Computer Science. All rights reserved.

关键词： Switches   Complexity theory   Fuzzy sets   Iterative methods   Computer science   Fuzzy logic   Sorting   Centroid   center-of-sets type reducer without sorting requirement (COSTRWSR)   direct approach (DA)   enhanced karnik-mendel (EKM) algorithm   enhanced iterative algorithm with stop condition (EIASC)   interval type-2 (IT2) fuzzy set   karnik-mendel (KM) algorithm   nonderivative-based direct approach (DAND)   simplified COSTRWSR (SC)   type-reduction  

摘要： Improving the efficiency of type-reduction algorithms continues to attract research interest. Recently, there has been some new type-reduction approaches claiming that they are more efficient than the well-known algorithms such as the enhanced Karnik-Mendel (EKM) and the enhanced iterative algorithm with stopping condition (EIASC). In a previous paper, we found that the computational efficiency of an algorithm is closely related to the platform, and how it is implemented. In computer science, the dependence on languages is usually avoided by focusing on the complexity of algorithms (using big O notation). In this article, the main contribution is the proposal of two novel type-reduction algorithms. Also, for the first time, a comprehensive study on both existing and new type-reduction approaches is made based on both algorithm complexity and practical computational time under a variety of programming languages. Based on the results, suggestions are given for the preferred algorithms in different scenarios depending on implementation platform and application context.

关键词： Work zone safety   Crash severity   Mixed Logit Model   Support vector machine   Cuckoo search optimization algorithm  

摘要： In the context of work zone safety, worker presence and its impact on crash severity has been less explored. Moreover, there is a lack of research on contributing factors by time-of-day. To accomplish this, first a mixed logit model was used to determine statistically significant crash severity contributing factors and their effects. Significant factors in both models included work-zone-specific characteristics and crash-specific characteristics, where environmental characteristics were only significant in the daytime model. In addition, results from parameter transferability test provided evidence that daytime and nighttime crashes need to be modeled separately. Further, to explore the nonlinear relationship between crash severity levels and time-of-day, as well as compare the effects of variables to that of the logit model and assess prediction performance, a Support Vector Machines (SVM) model trained by Cuckoo Search (CS) algorithm was utilized. Opening the SVM black-box, a variable impact analysis was also performed. In addition to the characteristics identified in the logit models, the SVM models also included the impacts of vehicle-level characteristics. The variable impact analysis illustrated that the termination area of the work zone is most critical for both daytime and nighttime crashes, as this location has the highest increase in severe injury likelihood. In summary, results of this study demonstrate that work zone crashes need to be modeled separately by time-of-day with a high level of confidence. Furthermore, results show that the CS-SVM models provide better prediction performance compared to the SVM and logit models.

关键词： Artificial Intelligence   Computer Science   general   Engineering Economics   Organization   Logistics   Marketing   Control   Robotics   Mechatronics   Performing Arts   Methodology of the Social Sciences  

关键词： Capital punishment   Death penalty   UN drug conventions   Human rights   Drug law reform  

摘要： Background: Research into capital punishment has focussed on the length of time it will take to abolish. It will take decades or centuries. A key moment in the movement to abolish the death penalty was the 1980s when the Second Optional Protocol to the ICCPR was developed. This was also the decade that the last significant changes were made to the United Nations drug conventions. At the time, awareness of the issue of capital punishment for drug offences was increasing around the world as more people were getting executed. This article looks at how western countries and the United Nations responded to Malaysia which introduced the mandatory death penalty for drug offences in 1982. Methods: Over 30,000 pages of documents have been accessed through the National Archives of Australia in Canberra. These have been photographed, scanned and converted to OCR. The most relevant folders have then been analysed through NVivo 12 to look for relevant mentions of the research question: capital punishment and Malaysia. All probative data is then presented in the article. Results: The data from National Archives suggests that the UN, Australia, and other western countries were happy to continue supporting Malaysia's drug policy and to elect it to high positions at UN meetings despite their public proclamations that they were opposed to the death penalty. Conclusion: Applying a critical juncture approach, the article concludes that the 1980s was a critical juncture in the movement to abolish the death penalty but abolitionist countries allowed capital punishment to continue for drug offences. This may have set back the abolition movement by decades.

关键词： Death penalty   Drugs   Drug offences   Human rights   War on drugs   Capital punishment   Drug control  

摘要： The last decade has seen a significant amount of progress in the struggle to abolish the death penalty for drug offences, a practice that is both illegal under international law and proven to be ineffective. Political, legal and policy developments at the international, regional and national level have led to a progressive shift away from capital punishment as a tool for drug control, resulting in a relatively sharp decrease in global executions. Yet a small number of countries, primarily in Asia, continue to aggressively pursue the policy, executing hundreds of disadvantaged individuals every year, often following trials that do not meet international standards of fairness. At the same time, populist rhetoric advocating for the death penalty for drugs is on the rise in the region, reinvigorating aggressive drug wars and threatening to undermine the framework of existing international legal obligations and unravel decades of progress.