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关键词： Carbon black   Cell culture media   Amino acid   Assessment   Toxicity  

摘要： Carbon black nanomaterial (CB-NM), as an industrial product with a large number of applications, poses a high risk of exposure, and its impact on health needs to be assessed. The most common testing platform for engineered (E)NMs is in vitro toxicity assessment, which requires prior ENM dispersion, stabilization, and characterization in cell culture media. Here, asymmetric flow field-flow fractionation (AF4) coupled to UV-Vis and dynamic light scattering (DLS) detectors in series was used for the study of CB dispersions in cell culture media, optimizing instrumental variables and working conditions. It was possible to disperse CB in a non-ionic surfactant aqueous solution due to the steric effect provided by surfactant molecules attached on the CB surface which prevented agglomeration. The protection provided by the surfactant or by culture media alone was insufficient to ensure good dispersion stability needed for carrying out in vitro toxicity studies. On the other hand, cell culture media in combination with the surfactant improved dispersion stability considerably, enabling the generation of shorter particles and a more favourable zeta potential magnitude, leading to greater stability due to electrostatic repulsion. It was demonstrated that the presence of amino acids in the culture media improved the monodisperse nature and stability of the CB dispersions, and resulted in a turn towards more negative zeta potential values when the pH was above the amino acid isoelectric point (IEP). Culture media used in real cell culture scenarios were also tested, and in vitro toxicity assays were developed optimizing the compatible amount of surfactant.

关键词： Smart homes   Access control   Servers   Emulation   Permission   Computer science   Safety   smart homes   reinforcement learning  

摘要： Smart home systems are both technologically and economically advancing rapidly. As people become gradually inalienable to smart home infrastructures, their security conditions are getting more and more closely tied to everyone's privacy and safety. In this paper, we consider smart apps, either malicious ones with evil intentions or benign ones with logic errors, that can cause property loss or even physical sufferings to the user when being executed in a smart home environment and interacting with human activities and environmental changes. Unfortunately, current preventive measures rely on permission-based access control, failing to provide ideal protections against such threats due to the nature of their rigid designs. In this paper, we propose CommandFence, a novel digital-twin-based security framework that adopts a fundamentally new concept of protecting the smart home system by letting any sequence of app commands to be executed in a virtual smart home system, in which a deep-q network (DQN) is used to predict if the sequence could lead to a risky consequence. CommandFence is composed of an Interposition Layer to interpose app commands and an Emulation Layer to figure out whether they can cause any risky smart home state if correlating with possible human activities and environmental changes. We fully implemented our CommandFence implementation and tested against 553 official SmartApps on the Samsung SmartThings platform and successfully identified 34 potentially dangerous ones, with 31 of them reported to be problematic Author: Please provide index terms/keywords for your article. To download the IEEE Taxonomy go to http://***/documents/taxonomy_*** ?> the first time to our best knowledge. Moreover, We tested our CommandFence on the 10 malicious SmartApps created by Jia et al. 2017, and successfully identified 7 of them as risky, with the missed ones actually only causing smartphone information leak (not harmful to the smart home system). We also

关键词： Design-based research   Coding   Computational Thinking   Powerful Ideas   ScratchJr  

摘要： This paper describes the iterative research and evaluation of the Coding as Another Language (CAL) curricu-lum that utilizes the free ScratchJr programming language in kindergarten to second grade. CAL was designed using principles of three theoretical frameworks: Curriculum Research Framework (CRF), which proposes differ-ent phases in the creation of research-based curriculum;Constructionism, which presents a computationally-rich project-based methodology based on identifying powerful ideas from a learning domain;and Positive Techno-logical Development, which intentionally integrates socio-emotional and ethical dimensions into curricular ex-periences. The pedagogical foundation of CAL involves the understanding of coding as a literacy, that is, putting developmentally-appropriate powerful ideas of computer science in conversation with those taught in language arts. The paper first describes CAL and then presents results from both a pilot study and a cluster randomized con-trolled trial that set to evaluate CAL's feasibility and impact on students' learning outcomes. Our findings showed that the CAL curriculum was not only feasible to implement, but also effective for improving coding skills. How-ever, CAL's impact on computational thinking is less clear given that in the cluster randomized controlled trial, both the control and the intervention groups improved equally on a measure of computational thinking.

关键词： Computer Science   Visualization   Uncertainty   Software   Cognition   Human Factors   Data Models   Recycling   Disease Rating   Journalism   Scientific Information   Behavior Of People   Average Treatment Effect   Population Of Persons   Forms Of Uncertainty   Lot Of Knowledge   Current Research In The Field   People Trying  

摘要： Artist Mare Hirsch is driven by data, but it wasn't always that way. After initially studying both classical and jazz guitar, Hirsch gravitated to music composition because it offered more of an authorship role. She scored films and created sound-art installations, always in search of ways for audiences to experience sound anywhere besides the concert hall stage.

关键词： Industries   Computer science   Conferences   Europe   Computer graphics   History   Standards  

摘要： "The Origins of Computer Graphics in Europe," is being published in two parts: Part 1, published in the March/April issue of IEEE Computer Graphics and Applications (IEEE CG & A), is subtitled "The Beginnings in Germany";Part 2, published in this May/June 2023 issue, is subtitled "The Early Spreading of Computer Graphics in Europe." I was a participant, contributor, and witness to the events reported here and I relate my personal story along with the broader history. Part 1 describes the origins and successful evolution of computer graphics in Germany, starting in 1965, and includes details of the people and subject matter of the earliest research groups. It describes the efforts undertaken to establish computer graphics as a proper academic discipline, including the founding of EUROGRAPHICS, and creation of institutes for both basic and applied research in computer graphics. Part 2 continues the story with a focus on activities contributing to the growth of the academic and industrial computer graphics communities across Europe and documents the two IFIP workshops held at Seillac and the development of the GKS Graphics Standard. Over the years, computer graphics gained respect and importance as a component of the computer science curricula and became an important tool and enabling technology for applications for industry and for the IT market in Europe.

摘要： Unlike whipping, which was quickly abolished following independence, India has continued to hold tightly to the noose's rope and remains a retentionist country to our present day. Notably, though the number of executions would fall dramatically in the first decades of India's postcolonial history, the list of crimes made punishable by death has grown ever longer in recent years. Rather than positing the continued presence of the death penalty as an anachronism ill-suited for a modern democracy, this article takes seriously the legal and discursive developments that allowed the most infamous of penal institutions to travel safely across India's twentieth century. From something that begun as a distilled expression of racialised colonial state power, like many other state institutions during this period, the death penalty would undergo a series of changes to remain relevant amidst new organizing political principles of representative democracy and popular will. Moving from the first formal efforts at abolition in the 1920s, through constitutional assembly debates in the 1940s, and Supreme Court judgements between 1967-83, the article positions capital punishment as a product of both deep colonial inheritances, and a particular process of postcolonial translation. Becoming fully couched in the language of popular sentiment by the culmination of this legal transformation, this violence would become well-positioned to grow within a national political culture increasingly organised around majoritarian expressions of national belonging.

关键词： campaigns   collaborative learning   interdisciplinary   pedagogy   professional skills   technology  

摘要： What role does advertising play in product development as part of owned media? For three years, a capstone advertising campaign course collaborated with STEM courses to form interdisciplinary teams composed of advertising, engineering, and computer science. The study provides insight into how teams can be more entrepreneurial by building on the strengths and techniques advertising students possess. Students, faculty, and external partners all saw the experiences as rewarding and valuable. Incorporating scrum project management gave more agency to advertising students while exposing them to product development processes commonly used by those who create technology. STEM students benefited from in-depth research to inform the products and see how advertising techniques can influence their development process. An overview of the approach, scrum project management, technology, assessment tools, lessons learned, and strategies to accomplish meaningful learning throughout the campaign collaborations with STEM students are provided. © The Author(s) 2022.

关键词： Kernel   Linux   Permission   Codes   Access control   Computer science   Computer bugs   Linux kernel   static analysis   permission check   bug detection  

摘要： Permission checks play an essential role in operating system security by providing access control to privileged functionalities. However, it is challenging for kernel developers to scalably verify the soundness of existing checks due to the large codebase and complexity of the kernel. In fact, Linux kernel contains millions of lines of code with hundreds of permission checks, and even worse, its complexity is fast-growing. This paper presents PeX, a static Permission check error detector for LinuX, which takes as input a kernel source code and reports any missing, inconsistent, and redundant permission checks. PeX uses KIRIN (Kernel InteRface based Indirect call aNalysis), a novel, precise, and scalable indirect call analysis technique. Over the interprocedural control flow graph built by KIRIN, PeX automatically identifies permission checks and infers the mappings between permission checks and privileged functions. For each privileged function, PeX examines all possible paths to the function to check if necessary permission checks are correctly enforced. We evaluated PeX on the latest stable Linux kernel v4.18.5 for three types of permission checks: Discretionary Access Controls (DAC), Capabilities, and Linux Security Modules (LSM). PeX reported 45 new permission check errors, 17 of which have been confirmed by the kernel developers.

关键词： Ancestral knowledge systems   Indigenous epistemologies   Decolonizing computing education   Sustainability   Participatory action research   Critical reflexivity  

摘要： This article offers Ancestral Computing for Sustainability (ACS) to dismantle the logics of settler colonialism that affect accessibility, identities, and epistemologies of computer science education (CSE). ACS centers Indigenous epistemologies in researching CSE across four public universities in the United States. This paper describes Ancestral Computing for Sustainability and explores reflections of two students engaging as researchers in ACS inquiry. Drawing on Indigenous methodologies and Participatory Action Research, they share their reflections as co-researchers in ACS through storywork. These critical reflections include their relationship to computing, observations of the interdependent work within ACS, ethics and sustainability, and their experiences within the focus groups. The article ends with recommendations for furthering ACS as a decolonial approach that centers Indigenous epistemologies in CSE. Recommendations for CSE education include Ancestral Knowledge Systems and adding sustainability as a topic within computing education pathways and building student-faculty relationships based on trust is recommended to foster students' academic and personal growth within CSE education and research.

关键词： Computer science   Visualization   Image color analysis   Collaboration   Rendering (computer graphics)   Market research   Biology  

摘要： Aesthetics for the visualization of biomolecular structures have evolved over the years according to technological advances, user needs, and modes of dissemination. In this article, we explore the goals, challenges, and solutions that have shaped the current landscape of biomolecular imagery from the overlapping perspectives of computer science, structural biology, and biomedical illustration. We discuss changing approaches to rendering, color, human-computer interface, and narrative in the development and presentation of biomolecular graphics. With this historical perspective on the evolving styles and trends in each of these areas, we identify opportunities and challenges for future aesthetics in biomolecular graphics that encourage continued collaboration from multiple intersecting fields.