Computational Soundness for Dalvik Bytecode

Automatically analyzing information flow within Android applications that rely on cryptographic operations with their computational security guarantees imposes formidable challenges that existing approaches for understanding an app's behavior struggle to meet. These approaches do not distinguish cryptographic and non-cryptographic operations, and hence do not account for cryptographic protections: f(m) is considered sensitive for a sensitive message m irrespective of potential secrecy properties offered by a cryptographic operation f. These approaches consequently provide a safe approximation of the app's behavior, but they mistakenly classify a large fraction of apps as potentially insecure and consequently yield overly pessimistic results. In this paper, we show how cryptographic operations can be faithfully included into existing approaches for automated app analysis. To this end, we first show how cryptographic operations can be expressed as symbolic abstractions within the comprehensive Dalvik bytecode language. These abstractions are accessible to automated analysis, and they can be conveniently added to existing app analysis tools using minor changes in their semantics. Second, we show that our abstractions are faithful by providing the first computational soundness result for Dalvik bytecode, i.e., the absence of attacks against our symbolically abstracted program entails the absence of any attacks against a suitable cryptographic program realization. We cast our computational soundness result in the CoSP framework, which makes the result modular and composable.Comment: Technical report for the ACM CCS 2016 conference pape

Representation of Africa online: sourcing practice and frames of reference

The dominant perspective on the representation of Africa in the western media claims that western media coverage is bias and crisis orientated and the liberal perspective claims that the coverage of Africa is not as negative as is often assumed. However, there is a paucity of literature on the representation of Africa online. This research enquiry is relevant because literature claims that the Internet has the potential to resolve the journalistic predicament of representing other culture through political participation and deliberation. But this requires a re-orientation of the sourcing practice of news organization to embrace sensitivity to and knowledge of African cultures. Moreover, the journalistic predicament can be resolved or not depending on the news gathering approach adopted by the news organization. Literature has identified two approaches, that is, ‘gatekeeping’ used mainly by dominant traditional media and ‘gatewatching’ used by alternative media in their quest to counter mainstream ideology. This study examines the impacts of the ‘gatewatching’ approach adopted by Africa Have Your Say (AHYS) website on its representation and frames of reference of Africa. It uses on-site observation, in-depth interviews and textual analysis to gather data. The study found that although the sourcing practice at the AHYS is elaborate and complex, the ‘gatewatching’ approach makes its susceptible to second level agenda setting. Hence, its frame repeats the attributes and tone used by the mainstream traditional media. However, a minority of users did not use repeat this frame in their comments

Establishing a meaningful human rights due diligence process for corporations : learning from experience of human rights impact assessment

The United Nations Special Representative of the Secretary-General on Business and Human Rights, Professor John Ruggie, has constructed a new international framework, which is set to become the cornerstone for all action on human rights and business at the international level. The principle of human rights due diligence (HRDD) is the central component of the corporate duty to respect human rights within that framework. This article argues that Ruggie's HRDD principle contains the majority of the core procedural elements that a reasonable human rights impact assessment (HRIA) process should incorporate. It is likely that the majority of corporations will adopt HRIA as a mechanism for meeting their due diligence responsibilities. However, in the context of the contentious debate around corporate human rights performance, the current state of the art in HRIA gives rise to concerns about the credibility and robustness of likely practice. Additional requirements are therefore essential if HRDD is to have a significant impact on corporate human rights performance – requirements in relation to transparency; external participation and verification; and independent monitoring and review

E-grocery challenges and remedies: Global market leaders perspective

The purpose of the study is to identify logistic elements germane to e-grocery businesses, and to reveal the challenges collateral with each logistic element. Further, it strives to create a better understanding of specific remedies that have been employed by top e-grocery retailers to overcome existing challenges while aligning identified challenges with Turban’s framework. Extensive semi-structured interviews were conducted with management staff in three of the top ten global online grocery retailers and another that was a market leader in a European country. The qualitative data collected was transcribed and coded using a non-hierarchical axial coding to identify emerging themes in content analysis. The results expose a range of challenges that could be compartmentalised into three broad categories, in harmony with the different stages of the order fulfilment process. Interestingly, the study found that most challenges were operational rather than tactical or strategic in nature. While the study expands existing knowledge, its revelation that most challenges lie in the management of roles and responsibilities domain is instructive. This makes it imperative for practitioners to focus on this specific area if meaningful improvement in e-grocery retailing performance is to be realised. This research offers a systematic understanding of supply and distribution challenges, including remedies utilised to ameliorate the effect of the challenges from the perspectives of the top companies in the industry. These remedies can be invaluable for existing and emerging e-grocers

Unbundling in Current Broadband and Next-Generation Ultra-Broadband Access Networks

This article overviews the methods that are currently under investigation for implementing multi-operator open-access/shared-access techniques in next-generation access ultra-broadband architectures, starting from the traditional "unbundling-of-the-local-loop" techniques implemented in legacy twisted-pair digital subscriber line access networks. A straightforward replication of these copper-based unbundling-of-the-local-loop techniques is usually not feasible on next-generation access networks, including fiber-to-the-home point-to-multipoint passive optical networks. To investigate this issue, the article first gives a concise description of traditional copper-based unbundling-of-the-local-loop solutions, then focalizes on both next-generation access hybrid fiber-copper digital subscriber line fiber-to-the-cabinet scenarios and on fiber to the home by accounting for the mix of regulatory and technological reasons driving the next-generation access migration path, focusing mostly on the European situation. © 2014 Taylor and Francis Group, LLC

Popular music and school music education: Chinese students' preferences and dilemmas in Shanghai, China

This empirical study investigates Chinese students’ popular music preferences in daily life and to what extent and in what ways they prefer learning popular music in school in Shanghai, China. Data were drawn from questionnaires completed by 1,730 secondary students (aged 12–17) and interviews with 60 students from 10 secondary schools, between September and October, 2011. Findings from these efforts were supplemented by and triangulated with data from interviews with 18 music teachers and school leaders. Findings revealed the cultural diversification and rational consumption of popular music by Chinese students in and out of school, as well as the cultural dilemmas those students confront due to their preferences for popular (Chinese and non-Chinese) and classical music in the school music curriculum. These findings can be interpreted as indicating that music and music education in formal or informal settings are complex cultural constructs that can be reinvented through the intertwined interplay of different actors concerned with the selection of music elements in a multileveled, multicultural world.postprin

Internet penetration and consumption inequality in China

Growing research shows that information technology accelerates economic growth and development, but the effect of Internet penetration on inequality is less well documented, especially about consumption inequality. On the one hand, Internet lowers transaction costs and offers equal access to online products especially beneficial for remote and poor populations, seemingly reducing inequality. On the other hand, uneven access to the Internet may increase divergences. This study examines the relationship between Internet penetration and consumption inequality. Using data from 155 counties available from 2010 to 2016 China Family Panel Studies, this study examines whether Internet penetration potentially impacts consumption inequality considering regional heterogeneity. Based on fixed‐effect models and the two‐stage least squares regressions, results suggest the Internet penetration may increase consumption inequality measured by the Gini index. Furthermore, higher education and over a certain Internet penetration rate buffer the positive impact of the Internet. In some cases, the Internet has smaller positive or even negative impacts on consumption inequality in regions with higher education levels and over threshold penetrations

Multi-Signal Informed Attention for Beat and Downbeat Detection

Processing multiple signal sources presents a challenge but also an opportunity in music information processing, especially when the sources provide complementary information. The attention mechanism paves the way toward addressing this challenge. In this paper, a novel transformer for beat and down-beat detection is proposed, named Informed Beat Transformer. It is theorised to both improve upon previous beat and downbeat detection models and take advantage of auxiliary information. Two experiments are run to test these two hypotheses. In the first experiment, it is directly compared to the Beat Transformer and found to have an average improvement of 0.005 in the F1 score across 4 datasets. The second experiment compares the Beat Transformer and madmom's beat tracker to the Informed Beat Transformer in a situation where a beat coherent signal stream is available, in this case a drum track. It was found to have a significant improvement to the Beat Transformer with an increase in F1 score of 0.702 and an increase of 0.018 to the madmom beat tracker. These results show the efficacy of the Informed Beat Transformer in both experimental settings

Use of an innovative model to evaluate mobility in seniors with lower-limb amputations of vascular origin: a pilot study

<p>Abstract</p> <p>Background</p> <p>The mobility of older individuals has often been only partially assessed, without considering all important aspects such as potential (available) versus effective (used) mobilities and the physical and psychosocial factors that modulate them. This study proposes a new model for evaluating mobility that considers all important aspects, applied here to lower-limb amputees with vascular origin. This model integrates the concepts of potential mobility (e.g. balance, speed of movement), effective mobility (e.g. life habits, movements in living areas) and factors that modulate these two types of mobility (e.g. strength, sensitivity, social support, depression). The main objective was to characterize potential and effective mobility as well as mobility modulators in a small sample of people with lower-limb amputations of vascular origin with different characteristics. The second objective of this pilot study was to assess the feasibility of measuring all variables in the model in a residential context.</p> <p>Methods</p> <p>An observational and transversal design was used with a heterogeneous sample of 10 participants with a lower-limb amputation of vascular origin, aged 51 to 83, assessed between eight and 18 months after discharge from an acute care hospital. A questionnaire of participant characteristics and 16 reliable and valid measurements were used.</p> <p>Results</p> <p>The results show that the potential mobility indicators do not accurately predict effective mobility, i.e., participants who perform well on traditional measures done in the laboratory or clinic are not always those who perform well in the real world. The model generated 4 different profiles (categories) of participants ranging from reduced to excellent potential mobility and low to excellent effective mobility, and characterized the modulating factors. The evaluations were acceptable in terms of the time taken (three hours) and the overall measurements, with a few exceptions, which were modified to optimize the data collected and the classification of the participants. For the population assessed, the results showed that some of the negative modulators (particularly living alone, no rehabilitation, pain, limited social support, poor muscle strength) played an important role in reducing effective mobility.</p> <p>Conclusion</p> <p>The first use of the model revealed interesting data that add to our understanding of important aspects linked to potential and effective mobility as well as modulators. The feasibility of measuring all variables in the model in a residential context was demonstrated. A study with a large number of participants is now warranted to rigorously characterize mobility levels of lower-limb amputees with vascular origin.</p