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关键词： Estimation   Drugs   Biological system modeling   Inference algorithms   Advertising   Computer science   Treatment effect estimation   variable decomposition   adjustment variables   confounder separation  

摘要： Causal Inference plays an important role in decision making in many fields, such as social marketing, healthcare, and public policy. One fundamental problem in causal inference is the treatment effect estimation in observational studies when variables are confounded. Controlling for confounding effects is generally handled by propensity score. But it treats all observed variables as confounders and ignores the adjustment variables, which have no influence on treatment but are predictive of the outcome. Recently, it has been demonstrated that the adjustment variables are effective in reducing the variance of the estimated treatment effect. However, how to automatically separate the confounders and adjustment variables in observational studies is still an open problem, especially in the scenarios of high dimensional variables, which are common in the big data era. In this paper, we first propose a Data-Driven Variable Decomposition (D2VD) algorithm, which can 1) automatically separate confounders and adjustment variables with a data-driven approach, and 2) simultaneously estimate treatment effect in observational studies with high dimensional variables. Under standard assumptions, we theoretically prove that our D2VD algorithm can unbiased estimate treatment effect and achieve lower variance than traditional propensity score based methods. Moreover, to address the challenges from high-dimensional variables and nonlinear, we extend our D2VD to a non-linear version, namely Nonlinear-D2VD (N-D2VD) algorithm. To validate the effectiveness of our proposed algorithms, we conduct extensive experiments on both synthetic and real-world datasets. The experimental results demonstrate that our D2VD and N-D2VD algorithms can automatically separate the variables precisely, and estimate treatment effect more accurately and with tighter confidence intervals than the state-of-the-art methods. We also demonstrated that the top-ranked features by our algorithm have the best prediction p

关键词： 盐津乌骨鸡   文化传承   品牌  

摘要： 品牌文化一直是农产品进行品牌宣传中常被忽视的因素。1978年以来,随着经济的不断发展,市场逐渐向完全竞争市场转变,消费者选择的空间逐渐扩大。在云南省打造“绿色食品牌”的背景下,盐津乌骨鸡产品的品牌文化与“绿色食品牌”相融合是本文的主要研究目标。本文运用了霍夫施泰德的洋葱皮理论从符号、英雄、礼仪和价值观4个维度出发,将盐津乌骨鸡绿色食品优势与品牌文化相融合,提高产品附加值。但发现该产品文化与生态定位不相容、文化标志模糊不清、绿色文化价值同质化等问题,政府和企业应通过围绕文化IP打造“绿色食品牌”、突出绿色农产品的文化定位、构建绿色文化展示区和对绿色品牌的管理进行文化品牌营销宣传,助推盐津县乌骨鸡产业的发展。

关键词： 计算机技术   物联网   核心技术  

摘要： 现如今我们国家经济、科技水平不断提升,许多新型技术、设备也应运而生。在物联网背景之下,人们的生活发生翻天覆地的变化,计算机科学技术的运用让人们学习、工作、生活更加便利。本文阐述了物联网的概念,分析物联网的三个核心技术,并且提出计算机科学技术对物联网的推动作用,以便进一步提升计算机科学技术水平,促进社会进步与发展。

关键词： Pricing   Computer science   Forward contracts   Finance   Forecasting   Machine learning   Electricity supply industry   Power markets  

摘要： Electricity Price Forecasting (EPF) IS A branch of forecasting at the interface of electrical engineering, statistics, computer science, and finance that focuses on predicting prices in wholesale electricity markets for a whole spectrum of horizons. These range from a few minutes (real-time/intraday auctions and continuous trading);through days (day-ahead [DA] auctions);to weeks, months, or even years (exchange and over-the-counter traded futures and forward contracts). DA markets are the workhorse of power trading, particularly in Europe, and a commonly used proxy for "the electricity price." The vast majority-up to 90%-of the EPF literature has focused on predicting DA prices. These are typically determined around noon during 24 uniform-price auctions, one for each hour of the next day. This has direct implications for the way EPF models are built.

关键词： Codes   Linear codes   Codecs   Generators   Telecommunications   Computer science   Technological innovation   Quaternary linear code   subfield code   weight distribution   simplicial complex  

摘要： In this paper, we mainly study quaternary linear codes and their binary subfield codes. First we obtain a general explicit relationship between quaternary linear codes and their binary subfield codes in terms of generator matrices and defining sets. Second, we construct quaternary linear codes via simplicial complexes and determine the weight distributions of these codes. Third, the weight distributions of the binary subfield codes of these quaternary codes are also computed by employing the general characterization. Furthermore, we present two infinite families of optimal linear codes with respect to the Griesmer Bound, and a class of binary almost optimal codes with respect to the Sphere Packing Bound. We also need to emphasize that we obtain at least 9 new quaternary linear codes.

关键词： civic engagement   political behavior   media   electronic   race   ethnicity   African-American  

摘要： This study examined associations between Black youth's engagement with hip-hop culture and their sociopolitical development (SPD) (e.g., critical social analysis, critical agency, and anti-racist activism). Participants included 499 Black adolescents recruited from across the United States through an online survey panel. Findings from regression analysis revealed the differential effects of rap media (music and music videos) and hip-hop media (e.g., blogs, video shows, radio) on youth's SPD. Black youth who consumed more hip-hop media and who interacted with artists on social media had more agency to address racism and reported engaging in more racial-justice activism. The frequency of youth's rap media usage was not consistently related to youth's SPD. However, youth's perceptions of rap (e.g., rap is empowering or misogynistic) were found to be directly associated with indicators of SPD. These findings provide insight into the potential influence of hip-hop culture beyond music on youth's racial-justice beliefs and actions.

关键词： Computer science   Feminist pedagogy   Gender gaps   Women students   Women of color  

摘要： The participation and engagement of traditionally underrepresented students remained low in computer science subjects and career paths, especially women and women of color. In terms of the urgent need to achieve intellectual diversity within the computer science field, many institutions strived to broaden the participation of women and women of color in computer science programs. However, access does not mean success. Effective pedagogical interventions are essential to change the classroom culture to support the retention and completion of women students in computer science. Research showed the promise of feminist pedagogy in eliminating gendered stereotypes, biases, and oppressions perpetuated within computer science education. The purpose of this article is to discuss course design considerations while adopting feminist pedagogy to promote gender parity in computer science, as indicated in feminist consciousness, collaborative learning, and reflexive learning. Further research and interventions are needed to address inequality issues in computer science in other contexts.

关键词： Routing   Costs   Blockchains   Contracts   Stochastic processes   Scalability   Computer science   Blockchain   payment channel   game theory   Shapley value  

摘要： Scaling blockchain efficiency is crucial to its widespread usage in which the payment channel is one of the most prominent approaches. With payment channels and the network they construct, two users can move some transactions off-chain to avoid expensive and time-consuming on-chain settlements. Existing works are devoted to designing high-throughput payment channel networks (PCNs) or efficient PCN routing policies to reduce the fee charged by intermediate nodes. In this paper, we investigate the PCN routing from a different perspective by answering whether the routing fee of transactions can be saved through being a bit more patient. The key idea is to reorder the processing sequence of atomic transactions, other than to handle each of them separately and immediately. We present two mechanisms, one is periodic transaction processing and the other is purely strategic waiting. In the former, the incoming transactions in a short time interval are processed collectively. We formulate an optimization model to minimize their total routing fee and derive the optimal permutation of processing transactions as well as the routing policy for each of them. A Shapley value based scheme is presented to redistribute the benefit of reordering among the transactions efficiently and fairly. In the latter, we model the waiting time of a strategic transaction on a single payment channel as the first passage time problem in queuing theory when the transaction value is higher than the channel balance upon its arrival. By capturing the balance dynamics, we are able to calculate the recursive expression of waiting time distribution that is useful to gauge a user's cost of patience. Experimental results manifest that our cost redistribution mechanism can effectively save routing fees for all the transactions, and the waiting time distribution coincides with the model well.

关键词： Sociology   Statistics   Evolutionary computation   Optimization   Heuristic algorithms   Search problems   Computer science   Evolutionary algorithm (EA)   irregular Pareto front   multiobjective optimization   projection  

摘要： This article proposes a simple yet effective multiobjective evolutionary algorithm (EA) for dealing with problems with irregular Pareto front. The proposed algorithm does not need to deal with the issues of predefining weight vectors and calculating indicators in the search process. It is mainly based on the thought of adaptively selecting multiple promising search directions according to crowdedness information in local objective spaces. Concretely, the proposed algorithm attempts to dynamically delete an individual of poor quality until enough individuals survive into the next generation. In this environmental selection process, the proposed algorithm considers two or three individuals in the most crowded area, which is determined by the local information in objective space, according to a probability selection mechanism, and deletes the worst of them from the current population. Thus, these surviving individuals are representative of promising search directions. The performance of the proposed algorithm is verified and compared with seven state-of-the-art algorithms [including four general multi/many-objective EAs and three algorithms specially designed for dealing with problems with irregular Pareto-optimal front (PF)] on a variety of complicated problems with different numbers of objectives ranging from 2 to 15. Empirical results demonstrate that the proposed algorithm has a strong competitiveness power in terms of both the performance and the algorithm compactness, and it can well deal with different types of problems with irregular PF and problems with different numbers of objectives.

关键词： Machine learning   Informatics   Critical infrastructure   Privacy   Medical services   Wireless communication   Computer science   Critical Infrastructure   Security   Federated Learning   Cyber incident  

摘要： Critical energy infrastructure (CEI) is specific engineering information about proposed or existing critical infrastructure. Modern critical infrastructures are increasingly turning into distributed, complex cyber-physical systems that need proactive protection and fast restoration to mitigate physical or cyber incidents or attacks. Most importantly, combined cyber-physical attacks are much more challenging and are expected to become the most intrusive attack. This is particularly true for the CEIs. During 2015, the Industrial Control Systems Cyber Emergency Response Team in the Unites States responded to more than 245 incidents; the energy sector tops the list with 32% incidents. Considering the importance of energy in our daily lives and its influence on other critical infrastructures, CEI requires significant attention comparatively. For example, the wind-turbine system is considered one of the most complex cyber-physical infrastructures, causing huge cascading effects to other CEIs, such as electrical power and energy systems and transportation, healthcare sector, communications, industry, and finance. Wind turbines are mainly composed of condition monitoring and operational data (i.e., supervisory command and data acquisition), including air temperature, air pressure, voltage, and power with multiple parameters and periodic characteristics.