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摘要： The article offers information on National Conference of State Legislatures' 2019 Legislative Summit in Nashville, Tennessee. It discusses the support of death penalty by Utah Representative Paul Ray and Colorado Senator Rhonda Fields. It also discusses the opposition of death penalty by New Hampshire Representative Renny Cushing and Wyoming Representative Jared Olsen.

关键词： Computer science   Computer science and engineering  

摘要： Information technology has transformed the collection, analysis, dissemination, and usage of data. Unfortunately, the variability of available resources, infrastructure, and technical expertise in the world’s diverse communities has prevented the digital revolution from benefiting all populations equally. Despite many technological advances, mobile technologies often fail to meet the needs of global development organizations because of poor design assumptions about the availability of infrastructure and resources. For example, the assumption of constant Internet connectivity to access cloud data makes some mobile technologies ill-suited to the long periods of disconnected operation required by many humanitarian organizations. For mobile technologies to be successful in resource-constrained environments they should be usable by minimally-trained users, deployable by resource-constrained organizations, and robust to intermittent power and networking outages. Designing flexible software tools that are configurable by global development organizations necessitates new abstractions that are usable by non-programmers with limited technical expertise. Our research focuses on developing complementary software frameworks that when used together create a new generation of mobile tools called “Open Data Kit 2”. ODK 2 is a configurable disconnected data management solution that can be adapted to meet the needs of under-served populations in resource-constrained environments. Our research aims to design, build, and evaluate multiple software frameworks that create an ensemble of mobile tools that can be used together or independently to produce mobile information systems that can adapt to challenged network environments.

关键词： Computer engineering   Computer science   Urban planning  

摘要： Understanding representativeness in cellular web logs at city scale is essential for web applications. Most of the existing work on cellular web analyses or applications is built upon data from a single network in a city, which may not be representative of the overall usage patterns since multiple cellular networks coexist in most cities in the world. In this thesis, we conduct a comprehensive investigation of multiple cellular networks in a city with a 100% user penetration rate. We study web usage patterns (e.g., internet access services) correlation and difference between diverse cellular networks in terms of spatial and temporal dimensions to quantify the representativeness of web usage from a single network in usage patterns of all users in the same city. Moreover, relying on three external datasets, we study the correlation between the representativeness and contextual factors (e.g., Point-of-Interest, population, and mobility) to explain the potential causalities for the representativeness difference. We found that contextual diversity is a key reason for representativeness difference, and representativeness has a significant impact on the performance of real-world applications. Based on the analysis results, we further design a correction model to address the bias of single cellphone networks and improve representativeness by 45.8%.

关键词： Computer science  

摘要： Determination of surface and hypersurface curvature is considered here. Focus is on the (1) introduction of four new methods for determining surface curvature in range images, (2) introduction of three new methods for determining surface curvature in volumes, (3) introduction of two new methods for determining hypersurface curvature in volumes, and (4) evaluative studies of such types of methods. The evaluative studies include evaluations of existing and new methods based on the accuracy of the determined curvatures, run times, and results on a set of curvature-based tasks.

关键词： Computer science  

摘要： The purpose of this research was to demonstrate a method of automating web application penetration testing using Burp Suite’s web vulnerability scanner and Python Selenium. This method is dependent on Burp Suite Professional, Selenium Google Chrome WebDriver, and Google Chrome Web Browser. The Python test script was written using the Page Object Model (POM) design pattern. The metrics analyzed were test time and the Burp scanner report results, which was measured in second and number of issues, respectively. The research was conducted to assist organizations to begin the implementation of automated web application penetration testing, compare the advantages and disadvantages of automated and manual testing, and analyze the benefits that automated testing can bring to an organization. The research found that using this method of automation functional testing and security testing can be performed at the same time. If applied to a Continuous Integration and Continuous Delivery (CI/CD) environment, the specific feature that is under development can be tested instead of the whole web application. This will increase an organization’s productivity, make security assessment more accessible to non-experts, produce a more secure web application, reduce an organization’s risk and financial loss, prevent system downtime and data loss, and have a positive affect customer retention and loyalty.

关键词： Petroleum engineering   Artificial intelligence   Computer science  

摘要： The challenges related to liquid loading have been observed during flow-back after hydraulic fracturing, as well as during the production phase, and are further aggravated with the high inclination angles found in deviated wellbores. Accurate prediction of the onset of liquid loading is of great importance in terms of production design and operation optimization. An experimental study was carried out to investigate the onset of liquid loading and a unified mechanistic model was developed to predict critical gas velocity for large diameter pipes. The experimental setup includes a 6-inch diameter acrylic test section which can be inclined from 0° to 90°. The study involves two-phase air-water flow in low-liquid-loading conditions to simulate a gas well. The critical gas velocity associated with the onset of liquid loading shows a strong function with the inclination angle and liquid flow rate in the current experimental study. A comparison with previous experimental data reveals that it also depends on the gas density and pipe diameter – i.e., it decreases with increasing gas density and increases when pipe diameter increases. A comprehensive model evaluation was conducted in the current study. It showed a large discrepancy for inclination angles higher than 45° and only a few existing models capturing all the effects of inclination angle, liquid flow rate, pressure, and pipe diameter. The experiments in this study provide new insights into the onset of liquid accumulation in large diameter deviated wells. The new mechanistic model fills the critical gap to enhance accuracy when predicting the onset of liquid loading especially for deviated and large-diameter wells. Accurate prediction of the onset of liquid loading requires a good prediction of pressure gradient and liquid holdup for segregated flow. In addition to the mechanistic model for the onset of liquid loading, the current study proposes a new hybrid-physics-data-driven algorithm to predict pressure gradient

关键词： Computer science  

摘要： Learning programming involves a variety of complex cognitive activities, from abstract knowledge construction to structural operations, which include program design,modifying, debugging, and documenting tasks. In this work, the objective was to explore and investigate the barriers and obstacles that programming novice learners encountered and how the learners overcome them. Several lab and classroom studies were designed and conducted, the results showed that novice students had different behavior patterns compared to experienced learners, which indicates obstacles encountered. The studies also proved that proper assistance could help novices find helpful materials to read. However, novices still suffered from the lack of background knowledge and the limited cognitive load while learning, which resulted in challenges in understanding programming related materials, especially code examples. Therefore, I further proposed to use the natural language generator (NLG) to generate code explanations for educational purposes. The natural language generator is designed based on Long Short Term Memory (LSTM), a deep-learning translation model. To establish the model, a data set was collected from Amazon Mechanical Turks (AMT) recording explanations from human experts for programming code lines. To evaluate the model, a pilot study was conducted and proved that the readability of the machine generated (MG) explanation was compatible with human explanations, while its accuracy is still not ideal, especially for complicated code lines. Furthermore, a code-example based learning platform was developed to utilize the explanation generating model in programming teaching. To examine the effect of code example explanations on different learners, two lab-class experiments were conducted separately in a programming novices’ class and an advanced students’ class. The experiment result indicated that when learning programming concepts, the MG code explanations significantly improved the l

关键词： Computer science  

摘要： How should a seller price multiple items in order to maximize their revenue from a single buyer? This question has been key in connecting research done by computer scientists and economists to applications such as online ad auctions and spectrum auctions. It was shown almost 40 years ago that if the buyer only cares for one item it is optimal for the seller to offer the buyer the item at a take-it-or-leave-it price. This elegant solution, however, may be far from optimal even for the case with a single buyer interested in just two items. Optimal auction design for two or more items is intricate for a number of reasons: the auctions may be bizarre, computationally hard to find or simply too complex to present to a bidder. Numerous results suggest that (under reasonable complexity assumptions) efficiently finding optimal auctions, even in some simple settings, is impossible. In this thesis, I will present numerous ways in which we try to circumvent these impossibility results in order to recover positive results. These include the study of different multi-item models and beyond-worst case analysis for mechanism design. I will also discuss recent advances in tournament design, a field at the intersection of mechanism design and social choice theory. For problems in this field we get around known impossibility results via approximations in order to find approximately strategy-proof tournament rules.

摘要： Carefully and conscientiously we shall study the questions, which affect the race most deeply and directly. Against the convict lease system, the Jim Crow car laws, lynchings and all other barbarities which degrade us, we shall protest with such force of logic and intensity of the soul that those who oppress us will either cease to disavow the inalienability and equality of human rights, or be ashamed to openly violate the very principles upon which this government was *** immorality of colored women is a theme upon which those who know little about them or those who maliciously misrepresent them love to descant. Foul aspersions upon the character of colored women are assiduously circulated by the press of certain sections and especially by the direct descendants of those who in years past were responsible for the moral degradation of their female slaves […] Dotted all over the country are charitable institutions for the aged, orphaned, and poor which have been established by colored women, just how many it is[End Page 33]difficult to state, owing to the lack of statistics bearing on the progress, possessions, and prowess of colored *** the late nineteenth and early twentieth centuries, black middle-class women around the United States formed a series of clubs to mobilize a racial uplift reform movement. They created kindergartens and reading groups.3They encouraged and guided the cultivation of black homes. And above all else, black clubwomen, as they came to be known, worked tirelessly to address the myriad challenges the black race faced with the rollback of civil rights following the end of Reconstruction and the steady rise of racial prejudice and antiblack violence.4By way of introduction into this essay’s focus on the archive of black clubwomen’s public writing and print culture, I offer a reading of the two passages above by Mary Church Terrell. Terrell was one of the most influential and powerful black women’s club leaders and the first preside

摘要： Students with disabilities are struggling to meet expectations in science at the national and local level. Many studies have linked difficulties with science content to difficult and technical vocabulary, and this has been evident at the local level, too. To try to improve science instruction for students with disabilities, the purpose of this study was to evaluate the implementation of computer-assisted science vocabulary modules with students with an intellectual disability and autism in an adapted environmental science class. This study aimed to answer how the implementation of computer-assisted vocabulary modules, which adhere to evidence-based practices of special education vocabulary instruction, affected the acquisition and application of science vocabulary terms with students with an intellectual disability and autism in an adapted environmental science class, as well as how the students were engaged in the computer-assisted instruction activities. This study implemented an action research design. The participants in this study included three students (n = 3) who were diagnosed with a moderate intellectual disability, autism, and a speech/language impairment who attended a weekly adapted environmental science class at their self-contained school. The students participated in computer-assisted vocabulary modules which included computer-assisted instruction features, vocabulary strategies including keyword mnemonics and graphic organizers, and the special education evidence-based practice of explicit instruction. The modules were developed surrounding the topic of photosynthesis, using Gagne’s nine events of instruction, psycholinguistic/schema theory, and dual coding theory, as well as South Carolina-Alt performance level descriptors. The effectiveness of the computer-assisted vocabulary modules was measured through data collection which included a pre- and posttest, formative assessments in each module, the Classroom Measurement of Achievement Engagement, an