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ISBN: (纸本)9781478015567;9781478022800

摘要： In The Emancipation Circuit Thulani Davis provides asweeping rethinking of Reconstruction by tracing how the fourmillion people newly freed from bondage created...

关键词： 死刑   大清律例   中华法治   治外法权   礼教之争  

摘要： 大清死刑在近两百年中外法制讨论中被极其夸张地烙上滥用、残酷的专政印记，最终造成晚清诸仕为迎列强而开法律西化之路。然而，法制不文明仅是西方夺取商业利益和治外法权，发动鸦片战争的借口，其根源在于法律帝国主义、尊孔禁令后的文明之争。将乾隆五年版《大清律例》中的死罪条文拆分成691种具体规定，解析死刑的分布格局和立法逻辑。多种策略分析后发现，死罪主要是杂犯、监候等基本不杀条文；律文立决条款只占10.27%,过半死罪由例文规定且立决率更高；立决以斩刑为主，绞刑以监候为主；死罪集中在刑律的人身犯罪，以伤亡侵财等加重结果为前提；立决只能是故意犯罪，死刑种类与尊卑、再犯、主犯及严重程度有关。正确看待《大清律例》传承了唐明律的高超立法技术，认识大清死刑中的律例关系、礼法合一、宽严相济，有助于重建和弘扬中华法治文明。

关键词： Computer science   Artificial intelligence  

摘要： Motivated by the need for fair algorithmic decision making in the age of automation and artificially-intelligent technology, this technical report provides a theoretical insight into adversarial training for fairness in deep learning. We build upon previous work in adversarial fairness, show the persistent tradeoff between fair predictions and model performance, and explore further mechanisms that help in offsetting this tradeoff.

关键词： Fourier transforms   Support vector machines   Computer science   Mathematics   Web studies  

摘要： Reactive maintenance in industry is associated with high downtime costs and the risk of catastrophic failure; predictive maintenance has the potential to mitigate these costs and risks. Currently, to analyze tool wear in CNC machines, rolling element bearing health, and other vibration-sensitive environments, accelerometers are used to gather vibration data. It is common in industry to use feature extraction (i.e., Fourier Transform) to identify fault frequencies in the vibration signals. Machine learning can also be used to identify patterns in the faulty equipment’s vibrations. Machine learning can provide accurate predictions on bearing and tool health from raw vibration data given enough data, training time, and computational power. However, connection to powerful computational resources (the cloud) is not always possible in remote locations or for security reasons. In many applications, it would be useful to leverage the power of machine learning in a local device. This practice is called edge computing, and its feasibility is investigated in this research. A small device is used to demonstrate a low-cost, easy to install solution. Data preprocessing, model training, and data analysis are all possible on a small local device. However, it is possible to save time and computational power by training the model elsewhere and simply using it for inference (to make predictions) on the small device. The prediction accuracy and time to compute of eight machine learning models was compared between a high-end CPU and a small device CPU over four data sets (two bearing health and two tool wear). From all the models, a convolutional neural network was shown to be optimal using compute time and accuracy as metrics. The small device CPU was able to make predictions in only 15 times the amount of time as the high-end CPU. In this way, the tests verified the feasibility of using an edge computing device with machine learning for machine condition monitoring.

关键词： Maps   3-D printers   Software   Design   Algorithms   Geometry   Designers   Computer science   Mathematics  

摘要： 3D printing for microfluidic device fabrication has received considerable interest in recent years, in part driven by the potential to dramatically speed up device development by reducing device fabrication time to the minutes timescale. Moreover, in contrast to traditional cleanroom-based fabrication processes that require manual production and stacking of a limited number of layers, 3D printing allows full use of the 3D fabrication volume to lay out microfluidic elements with complex yet compact 3D geometries. The Nordin group has successfully developed multiple generations of high resolution printers and materials for microfluidic devices that achieve this vision. However, because of the customizability of design in the Nordin microfluidics lab, finding settings that lead to a successful print can involve a taxing cycle of adjustments. The current 3D microfluidics design flow, which requires each student to find settings for each design, makes it difficult for new students to rapidly print successful designs with new components. In this thesis I present an Improved Microfluidic Design Approach (IMDA) that is based on a pre-defined component library. It allows students to reuse a library of components such that a new designer can utilize the work of more experienced predecessors, allowing the lab to avoid repeating the same parameter tuning process with each student. So far the tool has shown the feasibility of printing new designs based on previously tested components. Ultimately, my work demonstrates an attractive path to make the 3D printed microfluidic design experience more robust, repeatable, and easier for newcomers to learn.

关键词： Community colleges   Computer science education   Empirical research   Equity in STEM education  

摘要： This study aimed to understand the identity and attitude of students enrolled in computer science (CS) or programming-related course at community colleges nationwide. This study quantitatively evaluation data for estimating the relationships between students’ identity and attitudes toward computer science with prior programming experience and other demographic factors. I distributed the survey to community college faculty of computer science programs nationwide. Questions for this study were adapted from the Computing Attitude Survey developed by Weibe, Williams, Yang,&Miller (2003). Using two robust quantitative statistical methodologies, I investigated the correlations and predictability of previous programming experience, gender, race, and age with participants' attitudes toward computer science. This study drew its inspiration from prior works of Dorn and Tew (2015) and Chen, Haduong, Brennan, Sonnert, and Sadler (2018), whose studies looked at previous experiences in programming with a favorable attitude toward computer science. The primary independent variable was a students’ prior programming experience. Under evaluation, the dependent variables were students' programming experience and demographic characteristics such as race, gender, and age. This investigation showed a significant association between programming experience and attitude toward computer science. Among the demographic variables evaluated, students' racial identity was the only factor found highly correlated with attitudes toward computer science. Future work will consider the association between participants' accumulated college credit hours and specific programming language effects on computer science attitudes.

关键词： Design   Computer science   Hydraulic engineering   Materials science   Mathematics   Mechanics   Physics  

摘要： Strain path changes are common in complex automotive stampings, where sheet materials undergo a combination of drawing, stretching, and bending to achieve a desired part shape. Aluminum sheet alloys are increasingly used in vehicle structure light-weighting efforts, but limited formability and high levels of springback present challenges to the manufacturing and assembly processes. The current work explores springback levels in AA6016-T4 sheet after various pure bending operations, where sheets were first pre-strained in uniaxial, plane-strain, and biaxial tension. Finite element modeling of the pre-straining and subsequent bending operations will be performed using both isotropic and elasto-plastic self-consistent (EPSC) crystal plasticity approaches. Because the EPSC model incorporates backstresses informed by GND content, as measured via high-resolution EBSD, the predictions are more accurate than those of the isotropic model. The benefits and limitations of the current EPSC model, regarding accuracy of the predictions for the proposed strain path changes, are discussed.

关键词： Mechanical engineering   Morphology   Aerospace engineering   Applied Mathematics   Atomic physics   Biology   Computer science   Engineering   Industrial engineering   Mathematics   Mechanics   Physics   Plastics   Polymer chemistry   Textile Research  

摘要： Nonwoven fabrics are composed of groups of randomly oriented fibers bonded at multiple locations. The properties of nonwoven fabrics are highly affected by fiber selection, fiber orientation, and bond strength. The properties of nonwovens could be affected during the manufacturing process where the fabrics are subjected to rapid loading or from common applications like automotive and aerospace. Most nonwoven products are subjected to a variety of loading rates ranging from low-speed quasi-static loads to high-speed dynamic loads during their life cycles. This can be seen when nonwovens fabrics are stretched abruptly during motion. Investigating the nonwoven fabrics response to a wide range of loading rates is critical to improve the design of nonwoven products and optimize their fabrication process to ensure high quality during rapid manufacturing. A detailed study is proposed to address the disparity in nonwoven characterization to elucidate the relationship between loading-induced fiber reorientation and effective mechanical properties at different loading rates. The goal of this study is to understand the influence of loading rate on the mechanical behavior of nonwovens and identify when transitions in failure modes occur, and the underlying mechanisms associated with these transitions. The polypropylene samples are carded and thermally bonded with basis weights of 20 gsm and 30 gsm. The samples are tested in the machine direction (MD) and cross direction (CD). Three groups of samples with a diamond-shaped bonding pattern, a rectangular-shaped bonding pattern, and a circular-shaped bonding are studied. The tensile response of nonwovens is investigated at different loading rates: low strain rate (10-3 and 10-2 strain/s), intermediate strain rates (0.1 and 1 strain/s), and high strain rates tests (100 to 400 strain/s) by means of Instron 5802 universal testing machine and Split-Hopkinson tension bars. A low-speed camera and LED lighting are used to monitor deformat

关键词： Convolution   Computer architecture   Estimation   Feature extraction   Kernel   Computer science   Annotations   Surveillance   neural network   supervised learning  

摘要： Crowd counting is critical for numerous video surveillance scenarios. One of the main issues in this task is how to handle the dramatic scale variations of pedestrians caused by the perspective effect. To address this issue, this paper proposes a novel convolution neural network-based crowd counting method, termed Perspective-guided Fractional-Dilation Network (PFDNet). By modeling the continuous scale variations, the proposed PFDNet is able to select the proper fractional-dilation kernels for adapting to different spatial locations. It significantly improves the flexibility of the state-of-the-arts that only consider the discrete representative scales. In addition, by avoiding the multi-scale or multi-column architecture that used in other methods, it is computationally more efficient. In practice, the proposed PFDNet is constructed by stacking multiple Perspective-guided Fractional-Dilation Convolutions (PFC) on a VGG16-BN backbone. By introducing a novel generalized dilation convolution operation, the PFC can handle fractional dilation ratios in the spatial domain under the guidance of perspective annotations, achieving continuous scales modeling of pedestrians. To deal with the problem of unavailable perspective information in some cases, we further introduce an effective perspective estimation branch to the proposed PFDNet, which can be trained in either supervised or weakly-supervised setting once the branch has been pre-trained. Extensive experiments show that the proposed PFDNet outperforms state-of-the-art methods on ShanghaiTech A, ShanghaiTech B, WorldExpo'10, UCF-QNRF, UCF_CC_50 and TRANCOS dataset, achieving MAE 53.8, 6.5, 6.8, 84.3205.8, and 3.06 respectively.

摘要： This integrated article thesis provides an analysis of the past, present, and potential future state of Computer Science (CS) in K-12 education. Once implemented in optional courses at the secondary level, CS concepts and skills are now being integrated into other subject areas such as mathematics, science, and technology and other grades including K-8. This new state of K-12 CS education is explored through an analysis of 1) related theory reflected in the literature, 2) historical secondary school CS curriculum, 3) enrolment data and important issues related to equity, diversity, and inclusion, and 4) K-8 CS-related curriculum approaches currently being implemented in educational jurisdictions across Canada. The four articles in this dissertation employ a qualitative approach to research, drawing on a constructivist epistemology. Thematic Analysis is used in the comparative analysis of historical curriculum documents from Ontario and Document Analysis is used in comparing the various K-8 curriculum documents from across Canada. Together, the chapters included in this integrated article thesis provide a comprehensive analysis of K-12 CS education that supports educators, policy makers, and researchers in the field during a transformative time.