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摘要： No abstract available.

关键词： Recommender systems   Reinforcement learning   Cybernetics   Computer science   Cats   Training   Research and development   Deep reinforcement learning (DRL)   hierarchy   large action space   recommender system  

摘要： Deep reinforcement learning (DRL)-based recommender systems have recently come into the limelight due to their ability to optimize long-term user engagement. A significant challenge in DRL-based recommender systems is the large action space required to represent a variety of items. The large action space weakens the sampling efficiency and thereby, affects the recommendation accuracy. In this article, we propose a DRL-based method called deep hierarchical category-based recommender system (DHCRS) to handle the large action space problem. In DHCRS, categories of items are used to reconstruct the original flat action space into a two-level category-item hierarchy. DHCRS uses two deep Q-networks (DQNs): 1) a high-level DQN for selecting a category and 2) a low-level DQN to choose an item in this category for the recommendation. Hence, the action space of each DQN is significantly reduced. Furthermore, the categorization of items helps capture the users' preferences more effectively. We also propose a bidirectional category selection (BCS) technique, which explicitly considers the category-item relationships. The experiments show that DHCRS can significantly outperform state-of-the-art methods in terms of hit rate and normalized discounted cumulative gain for long-term recommendations.

关键词： environmental destruction   dreams   collective unconscious   Jewish myth   borderland' personality   sandplay  

摘要： The author, although an analyst, is an initiate into the topic of environmental destruction. Following Wendell Berry, she enters the dark and begins a journey of dream-like reflection, weaving images from her own dream and drawing on the work of Vaughan, Bernstein, Soloveitchik and Sacks. She asks, 'not if but where does climate change enter the room?'. The second half of the paper focuses on the manifestations of environmental destruction in dreams and sandplay from three patients and one dream group participant. The paper argues that the analyst must see and intuit before our patients can access the objective layer of environmental destruction in dreams and symbolic material. In this way, the climate becomes the wounded patient, and the analyst as wounded healer must first access his/her own relationship to the wounds inside. Finally, using an ancient Jewish mythological story of Rabbi Shimon bar Yochai, the author argues that Jungian analysts must work to find balance between the inner world of depth psychology and the outer world with its challenges and problems that include environmental destruction.

关键词： Resource management   Ash   Interference   Bandwidth   Virtualization   Parallel architectures   Computer science   Multitenant   over-provisioning space (OPS)   solid-state drives (SSDs)   virtualization   workload characteristic  

摘要： Sharing a flash-based solid-state drive (SSD) among multiple tenants has become a common practice to improve storage utilization and cost efficiency. Meanwhile, how to allocate limited storage resources, especially the over-provisioning space (OPS) resources, among competitive tenants has emerged as a critical problem. The OPS refers to additional user-invisible storage space, whose size influences garbage collection (GC) efficiency. Due to unawareness of workload characteristics of different tenants, prior studies on multitenant OPS allocation lead to suboptimal SSD performance. In this article, we propose a novel workload-adaptive OPS allocation scheme for multitenant SSDs, called WA-OPShare. It targets an OPS sharing scheme that dynamically allocates the OPS among tenants to improve overall SSD performance. Two models are developed to identify underutilized storage space and predict the OPS-induced performance benefit of each tenant, respectively. Guided by the models, WA-OPShare regularly releases the underutilized storage space and then reallocates it to the tenant who can benefit the most. Experimental results show that compared to the traditional Partition and Sharing schemes, WA-OPShare improves the performance by up to 40.3% and 31.2%, and reduces the write amplification by up to 37.0% and 17.5%, respectively.

关键词： Neurons   Biological neural networks   Safety   Robustness   Input variables   Computer science   Venus   Abstract analysis   complete verification   input refinement   input splitting   neural network verification  

摘要： Safety and robustness properties are highly required for neural networks deployed in safety-critical applications. Current complete verification techniques of these properties suffer from the lack of efficiency and effectiveness. In this article, we present an efficient complete approach to verify safety and robustness properties of neural networks through incrementally determinizing activation states of neurons. The key idea is to generate constraints via layerwised splitting that make activation states of hidden neurons become deterministic efficiently. These constraints are then utilized for refining inputs systematically so that abstract analysis over the refined input can be more precise. Our approach decomposes a verification problem into a set of subproblems via layerwised input space splitting. The property is then checked on each subproblem, where the activation states of at least one hidden neurons will be determinized. Further checking is accelerated by constraint-guided input refinement. We have implemented a parallel tool called LayerSAR to verify safety and robustness properties of ReLU neural networks in a sound and complete way, and evaluated it extensively on several benchmark sets. Experimental results show that our approach is promising, compared with complete tools, such as Planet, Neurify, Marabou, ERAN, Venus, Venus2, and nnenum in verifying safety and robustness properties on the benchmarks.

摘要： Sociologists of race and ethnicity have convincingly demonstrated that cultural categorizations are affected by racialization. For example, some music genres are clearly dominated by people of color (e.g., rap, soul, r&b), whereas others are particularly popular among whites (e.g., rock, country, classical). However, we know relatively little about how habitual such racialized categorizations are for people. We offer an integrated approach of cultural-sociological insights on the implicit underpinnings of categorization processes to understand how implicit, "nondeclarative" aspects of racial association lie at the heart of the-often, but not always, unintentional-(re)production of racialized cultural categories. We use an Implicit Association Test in combination with a survey (n = 920) to study the connection between rock music and whiteness, and rap music and blackness. First, we find a relationship between whiteness/blackness and having a preference for rock/rap. Second, we demonstrate that the racial associations regarding these genres are firmly grounded in non-declarative knowledge and that this is widely shared across racial groups, albeit somewhat more among people of color.

关键词： Public healthcare   Engineering students   Diseases   Medical services   Computer hacking   Task analysis   Pandemics   Computer science   design thinking   disease   electrical engineering   hackathon   interdisciplinary   outbreaks   public health   rapid prototyping  

摘要： Contribution: Although engineering hackathon events are common, this is one of the first reports of such an event used for the purpose of teaching engineering students about public health concepts. Results from this study suggest that hackathons are an effective format for teaching topics that are not core to the engineering discipline in a short period of time. Background: The current COVID-19 pandemic highlighted the essential role that computer scientists and engineers have in controlling disease outbreaks. However, engineering programs generally do not provide training on public health issues. Thus, there is a critical need to develop innovative and engaging ways to educate engineering students about public health without interfering with required discipline-specific content. Intended Outcomes: Hackathons, short-term events, held outside of the classroom, can provide an engaging and effective method for increasing the interest and knowledge of engineering students in disease outbreaks. In this article, the effectiveness of a hack day in increasing the interest and knowledge of engineering students in disease outbreaks is assessed. Application Design: One-hundred-six undergraduate students, 30 of whom were engineering majors, participated in a multidisciplinary disease focused hackathon. Student learning and engagement during the hackathon was assessed for the 30 engineering students that participated through pre- and post-event surveys. Findings: The results indicated that the hackathon increased both content knowledge and engagement of engineering students in public health issues. Additionally, students gained an increased understanding of public health professions and how they can contribute to disease tracking, prevention, and treatment. Therefore, hackathons are an effective and efficient tool for teaching engineering students about topics outside of their discipline.

关键词： Computer science   Electrical and electronic engineering   Photonic devices  

摘要： Neuromorphic computing using photonic hardware is a promising route towards ultrafast processing while maintaining low power consumption. Here we present and numerically evaluate a hardware concept for realizing photonic recurrent neural networks and reservoir computing architectures. Our method, called Recurrent Optical Spectrum Slicing Neural Networks (ROSS-NNs), uses simple optical filters placed in a loop, where each filter processes a specific spectral slice of the incoming optical signal. The synaptic weights in our scheme are equivalent to the filters' central frequencies and bandwidths. Numerical application to high baud rate optical signal equalization (>100 Gbaud) reveals that ROSS-NN extends optical signal transmission reach to > 60 km, more than four times that of two state-of-the-art digital equalizers. Furthermore, ROSS-NN relaxes complexity, requiring less than 100 multiplications/bit in the digital domain, offering tenfold reduction in power consumption with respect to these digital counterparts. ROSS-NNs hold promise for efficient photonic hardware accelerators tailored for processing high-bandwidth (>100 GHz) optical signals in optical communication and high-speed imaging applications.

关键词： Careers   Computer science   Policy  

摘要： Three charts from the world of research, selected byNatureeditors.

关键词： genetic algorithm   BIM technology   construction   computer science  

摘要： BIM technology is a breakthrough in the construction industry whose application is of great value, and the engineering design, engineering budget and cost control combined with BIM technology have been developed rapidly. Therefore, in this paper, BIM technology is adopted to optimise the construction mode, and the genetic algorithm is selected to solve the scheduling model of construction. By applying an interdisciplinary research method combined with computer science and technology, an intelligent optimisation model of construction can provide a new research perspective and technical method for the development of the construction industry.