Dynamic Virtual Page-based Flash Translation Layer with Novel Hot Data Identification and Adaptive Parallelism Management

Solid-state disks (SSDs) tend to replace traditional motor-driven hard disks in high-end storage devices in past few decades. However, various inherent features, such as out-of-place update [resorting to garbage collection (GC)] and limited endurance (resorting to wear leveling), need to be reduced to a large extent before that day comes. Both the GC and wear leveling fundamentally depend on hot data identification (HDI). In this paper, we propose a hot data-aware flash translation layer architecture based on a dynamic virtual page (DVPFTL) so as to improve the performance and lifetime of NAND flash devices. First, we develop a generalized dual layer HDI (DL-HDI) framework, which is composed of a cold data pre-classifier and a hot data post-identifier. Those can efficiently follow the frequency and recency of information access. Then, we design an adaptive parallelism manager (APM) to assign the clustered data chunks to distinct resident blocks in the SSD so as to prolong its endurance. Finally, the experimental results from our realized SSD prototype indicate that the DVPFTL scheme has reliably improved the parallelizability and endurance of NAND flash devices with improved GC-costs, compared with related works.Peer reviewe

A New Approximation Method for Constant Weight Coding and Its Hardware Implementation

In this chapter, a more memory-efficient method for encoding binary information into words of prescribed length and weight is presented. The solutions in existing work include complex float point arithmetic or extra memory overhead which make it demanding for resource-constrained computing platform. The solution we propose here solves the problems above yet achieves better coding efficiency. We also correct a crucial error in previous implementations of code-based cryptography by exploiting and tweaking the proposed encoder. For the time being, the design presented in this work is the most compact one for any code-based encryption schemes. We show, for instance, that our lightweight implementation of Niederreiter encrypting unit can encrypt approximately 1 million plaintexts per second on a Xilinx Virtex-6 FPGA, requiring 183 slices and 18 memory blocks

The Role of Entrepreneurship and Spirituality in the Provision of Elective Social Enterprise Courses in Business Schools

The final chapter in this section, chapter ten, Cherry Cheung, Sujun Fieldhouse and Caleb Kwong examine the extent to which the spirituality of a university may impact its decision to offer social enterprise courses as part of their business curriculum. Universities face increasing pressures from stakeholders to produce moral, civically aware and socially responsible citizens who will create positive change in their societies. Because of their concern and focus on social, economic, environmental and now spiritual ‘bottom-lines’, social enterprises courses are seen as one way of engaging in the conversations to examine transformational shifts in society. Using data from 494 business schools accredited by AACSB in the US, Cheung, Fieldhouse and Kwong found that, alongside structural differences, universities with higher entrepreneurship orientation, as well as the presence of spirituality markers, such as sustainability, diversity and religious orientations, are more likely to be offering social enterprise courses for business students, after controlling for other factors. This is an important finding, confirming that spirituality has a role to play in supporting a broader education experience that has the potential to develop socially responsible citizens who have the awareness to create transformational social changes. Thus, the study alerts the wider academic community of the contributions that social enterprise courses can make in creating social change, particularly for those without a strong emphasis of spirituality that may struggle to see the need to offer such courses

New Detections of Optical Emission from Kiloparsec-scale Quasar Jets

We report initial results from the detection of optical emission in the arcsecond-scale radio jets of two quasars utilizing images from the {\it Hubble Space Telescope} archive. The optical emission has a very knotty appearance and is consistent with synchrotron emission from highly relativistic electrons in the jet. Combining these observations with those of previously reported features in other quasars, an emerging trend appears to be that their radio-to-optical spectral indices are steeper than those of similar features in jets of lower power radio sources.Comment: 4 pgs, 2 figs, Proc of The Physics of Relativistic Jets in the Chandra and XMM Era workshop, eds. G. Brunetti, D.E. Harris, R.M. Sambruna, and G. Setti, submitted to New Astronomy Review. Quality of figure 1 degraded to fit into preprint server. Includes elsart.cls fil

Key-point Detection based Fast CU Decision for HEVC Intra Encoding

As the most recent video coding standard, High Efficiency Video Coding (HEVC) adopts various novel techniques, including a quad-tree based coding unit (CU) structure and additional angular modes used for intra encoding. These newtechniques achieve a notable improvement in coding efficiency at the penalty of significant computational complexity increase. Thus, a fast HEVC coding algorithm is highly desirable. In this paper, we propose a fast intra CU decision algorithm for HEVC to reduce the coding complexity, mainly based on a key-point detection. A CU block is considered to have multiple gradients and is early split if corner points are detected inside the block. On the other hand, a CU block without corner points is treated to be terminated when its RD cost is also small according to statistics of the previous frames. The proposed fast algorithm achieves over 62% encoding time reduction with 3.66%, 2.82%, and 2.53% BD-Rate loss for Y, U, and V components, averagely. The experimental results show that the proposed method is efficient to fast decide CU size in HEVC intra coding, even though only static parameters are applied to all test sequences

Effects of macrosegregation and microstructure on the corrosion resistance and hardness of a directionally solidified Zn-5.0wt.%Mg alloy

This study aims to analyze the influence of macrosegregation on microstructure evolution, and of microstructure length scale on the corrosion resistance of a Zn-5.0wt.%Mg alloy casting. The analyzed samples were taken along the length of castings unidirectionally solidified in unsteady state conditions of heat extraction. Microstructure characterization, microhardness, linear polarization and electrochemical impedance spectroscopy (EIS) tests were performed. A unique type of microstructure was observed, characterized essentially by a morphology typified by idiomorphic MgZn2 crystals in a “complex eutectic mixture” [coexistence of stable (Zn+Mg2Zn11) and metastable (Zn+MgZn2) eutectics]. The correlation between thermal and microstructural parameters, permitted experimental growth laws, correlating the evolution of the lamellar eutectic spacing with the cooling rate to be established. Vickers microhardness and electrochemical corrosion tests showed that more refined microstructures associated with higher experimental cooling rates, are related to a better set of higher hardness and corrosion resistance221CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQCOORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP155863/2013-4; Project i-link0944; 166912/2017-4não tem2012/08494-0; 2013/15478-3; 2013/25452-1; 2013/23396-7; 2014/50502-

The Point of Origin of the Radio Radiation from the Unresolved Cores of Radio-Loud Quasars

Locating the exact point of origin of the core radiation in active galactic nuclei (AGN) would represent important progress in our understanding of physical processes in the central engine of these objects. However, due to our inability to resolve the region containing both the central compact object and the jet base, this has so far been difficult. Here, using an analysis in which the lack of resolution does not play a significant role, we demonstrate that it may be impossible even in most radio loud sources for more than a small percentage of the core radiation at radio wavelengths to come from the jet base. We find for 3C279 that $\sim85$ percent of the core flux at 15 GHz must come from a separate, reasonably stable, region that is not part of the jet base, and that then likely radiates at least quasi-isotropically and is centered on the black hole. The long-term stability of this component also suggests that it may originate in a region that extends over many Schwarzschild radii.Comment: 7 pages with 3 figures, accepted for publication in Astrophysics and Space Scienc

Envelhecimento e doenças neurodegenerativas crônicas na Amazônia brasileira: implantação de novas metodologias de avaliação em pacientes com declínio cognitivo leve e doença de Alzheimer

By 2025, the number of elderly people in the world will double and by 2050 will reach around two billion individuals, with the majority of them in developing countries. Alzheimer's disease (AD) is the fourth disease that most compromises the quality of life in elderly. This work aims to suggest new methodologies for evaluating elderly people with mild cognitive impairment and Alzheimer‟s disease, introducing a Brazilian version of the TSM-"Test Your Memory" and showing the performance fo this people in tests from CANTAB. It is an analytical, retrospective, longitudinal case-control study, performed at the Laboratory of Neurodegeneration and Infection, University Hospital João de Barros Barreto, from January 2009 to January 2011. Ninety five individuals 65 years old or older were divided in three groups: Alzheimer's disease (AD, n = 21), mild cognitive impairment (DCL, n = 31) and control (n = 43). Patients with previous stroke, primary depression, head injury, other dementias and other neuropsychiatric disorders, and serious visuo-auditory deficits were excluded. The participants were submitted to an initial assessment, screening with GDS-5 and DSM-IV, the International Physical Activity Questionnaire (IPAQ), CERAD neuropsychological test battery and the TSM - Test Your Memory (Brazilian version).Statistical analysis was performed using one-way ANOVA, defining the p-value<0.05 to detect significant differences. Female individuals of mixed ethnicity, aged 70 to 79 years predominated in all groups. The average MMSE score between the three groups was significantly different (control: 26.6± 2.2; DCL: 25.1 ± 2.6, DA: 17.3 ± 4.9, p <0.05), however, the TSM proved to be a more sensitive test to distinguish DCL patients from AD (control: 42.4± 5; DCL: 35.5 ± 7.7, DA: 25.7 ± 8, p <0.01 ). The three groups had different mean scores. In the CERAD word list, clock test, TNBr and phonological verbal fluency. The performance in TSM was significantly lower in DCL and AD groups than in the control group. And DA group was worse in this test than the DCL group too. The tests and measurements of CANTAB that best separate the three groups from the performance obtained were RVP A‟, PAL-trials to success and PAL-total errors in 6 patterns phase. Good correlations were found between the TSM and other tests, especially with the MMSE (Pearson‟s coefficient r = 0.79, p <0.0001) and clock test (r = 0.76, p <0.0001), as well as good correlations between the measures of PAL and TSM and MMSE. Physical activity level, in the control group was higher than in all other groups. When the level of physical activity and performance on cognitive tests were correlated, there were no significant differences in the different groups, except by a better performance in word recall test from CERAD, and word list in DCL group (DCL "active":4.7 ± 1.8; DCL"not active": 3 ± 1.5,p <0.01). Taken as a Whole, these results suggest that the application of automated automated neuropsychological tests associated with routine clinical tests and TYM, improve the clinical assessment´s sensitivity and reliability, especially in the early stages of dementia where the precoceous and accurate diagnosis are essential to guide therapeutic actions, drugs or behavioral modifications.Em 2025 o número de idosos no mundo irá dobrar e por volta de 2050 alcançará dois bilhões de indivíduos, estando a maioria em países desenvolvidos. A doença de Alzheimer (DA) é a quarta doença que mais compromete a qualidade de vida dos idosos. Este trabalho pretende sugerir novas metodologias de avaliação de pacientes com declínio cognitivo e doença de Alzheimer, apresentando uma versão brasileira a partir da versão original em língua inglesa intitulada “Test Your Memory” TYM (“teste sua memória- TSM), bem como mostrar os resultados do desempenho dos idosos na bateria de testes neuropsicológicos de Cambridge (CANTAB). Trata-se de estudo analítico, transversal retrospectivo do tipo caso-controle, realizado em pacientes do ambulatório de Geriatria do Hospital Universitário João de Barros Barreto, e em voluntários da comunidade no período de janeiro de 2009 a janeiro de 2011. Participaram 95 indivíduos com 65 ou mais anos de idade, divididos em 3 grupos: Alzheimer (DA, n=21), declínio cognitivo (DCL, n=31) e controle (n=43). Foram excluídos pacientes com história de acidente vascular encefálico (AVE), depressão primária, trauma cranioencefálico, outras demências, outras patologias neuropsiquiátricas e déficits visuo-auditivos limitantes. Os participantes foram submetidos à avaliação inicial, triagem com GDS-5 e DSM-IV, ao Questionário Internacional de Atividades Físicas (IPAQ), testes neuropsicológicos da bateria CERAD, teste do relógio, TSM (versão adaptada para o Português) e a bateria de Alzheimer do CANTAB. A análise estatística foi realizada empregando-se ANOVA, um critério, definindo-se o valor p<0,05 como significante. Houve predomínio em todos os grupos de indivíduos do gênero feminino, de cor parda, na faixa etária de 70 a 79 anos. A média de pontuação do MEEM entre os três grupos foi diferente (controle: 26,6±2,2; DCL: 25,1±2,6; DA: 17,3±4,9; p<0,05), entretanto o TSM mostrou ser uma ferramenta de triagem mais confiável para distinguir os pacientes DCL dos DA (controle: 42,4±5; DCL: 35,5±7,7; DA: 25,7±8; p<0,01). Na lista de palavras do CERAD, teste do relógio, TNBR e na fluência verbal fonológica os três grupos apresentaram diferenças significantes na média de pontos obtidos. A média da pontuação total no TSM foi significativamente menor nos grupos DCL e DA do que no grupo controle, e no grupo DA em relação ao DCL. Os testes e medidas do CANTAB que separam os três grupos pelo desempenho obtido são: RVP A‟, número de tentativas para o sucesso e total de erros na fase de 6 figuras do PAL. Foram encontradas boas correlações entre o TSM e outros testes, principalmente com o MEEM (Coeficiente de Pearson, r = 0,79; p<0,0001) e teste do relógio (r = 0,76; p<0,0001), bem como boa correlação entre as medidas do PAL e a pontuação do TSM e o MEEM. O nível de atividade física no grupo controle foi maior do que em todos os outros grupos. Ao ser correlacionado o nível de atividade física e o desempenho nos testes cognitivos, não foram observadas diferenças significativas nos diferentes grupos, exceto pela evocação de palavras no grupo DCL. Tomados em conjunto os resultados sugerem que a aplicação de testes neuropsicológicos automatizados associados aos testes da rotina clínica e ao TSM aumentam a resolução e a confiabilidade das análises particularmente no estágio inicial das síndromes demenciais onde a precocidade e a precisão diagnóstica são fundamentais para orientar as ações terapêuticas, sejam elas medicamentosas e/ou comportamentais

A Multi-band Study of the Remarkable Jet in Quasar 4C+19.44

We present arcsecond-resolution data in the radio, IR, optical, and X-ray for 4C+19.44 (=PKS 1354+195), the longest and straightest quasar jet with deep X-ray observations. We report results from radio images with half to one arcsecond angular resolution at three frequencies, plus Hubble Space Telescope and Spitzer data. The Chandra data allow us to measure the X-ray spectral index in 10 distinct regions along the 18'' jet and compare with the radio index. The radio and X-ray spectral indices of the jet regions are consistent with a value of $\alpha =0.80$ throughout the jet, to within $2\sigma$ uncertainties. The X-ray jet structure to the south extends beyond the prominent radio jet and connects to the southern radio lobe, and there is extended X-ray emission, both in the direction of the unseen counter-jet, and also coincident with the northern radio lobe. This jet is remarkable because its straight appearance over a large distance allows the geometry factors to be taken as fixed along the jet. Using the model of inverse Compton scattering of the cosmic microwave background (iC/CMB) by relativistic electrons, we find that the magnetic field strengths and Doppler factors are relatively constant along the jet. If instead the X-rays are synchrotron emission, they must arise from a population of electrons distinct from the particles producing the radio synchrotron spectrum