From the Information Bottleneck to the Privacy Funnel

We focus on the privacy-utility trade-off encountered by users who wish to disclose some information to an analyst, that is correlated with their private data, in the hope of receiving some utility. We rely on a general privacy statistical inference framework, under which data is transformed before it is disclosed, according to a probabilistic privacy mapping. We show that when the log-loss is introduced in this framework in both the privacy metric and the distortion metric, the privacy leakage and the utility constraint can be reduced to the mutual information between private data and disclosed data, and between non-private data and disclosed data respectively. We justify the relevance and generality of the privacy metric under the log-loss by proving that the inference threat under any bounded cost function can be upper-bounded by an explicit function of the mutual information between private data and disclosed data. We then show that the privacy-utility tradeoff under the log-loss can be cast as the non-convex Privacy Funnel optimization, and we leverage its connection to the Information Bottleneck, to provide a greedy algorithm that is locally optimal. We evaluate its performance on the US census dataset

Analisis Kualitas Layanan Website Bukalapak Terhadap Kepuasan Pengguna Menggunakan Metode Webqual 4.0

Pertumbuhan Teknologi Informasi dan Komunikasi yang demikian pesat menjadikan website sebagai bagian yang tidak terpisahkan dari sebuah perusahaan dalam hal kualitas layanan bagi pelanggan khususnya pada website Bukalapak.com. layanan yang baik menjadikan alasan konsumen lebih tertarik untuk berbelanja secara online, Dengan itu suatu website perlu diukur untuk mengetahui tingkat kepuasan pelanggan. Dalam penelitian ini, kualitas website Bukalapak.com diukur dengan menggunakan metode Webqual 4.0. Webqual merupakan instrumen yang menilai kualitas suatu website. Responden dalam penelitian ini adalah pengguna website. Jumlah sampel yang digunakan dalam penelitian ini sebanyak 45 responden. Data penelitian diperoleh dari hasil penyebaran kuisoner terhadap responden.Teknik analisis data menggunakan analisis regresi linier berganda dengan menggunakan software SPSS versi 24.0 for windows.Dari hasil penelitian dapat disimpulkan bahwa secara simultan kualitas website berpengaruh terhadap kepuasan pengguna. Sedangkan secara parsial terdapat dua dimensi Webqual yaitu kualitas kegunaan (Usability) dan kualitas informasi (Information Quality) tidak mempengaruhi kepuasan pengguna secara signifikan. Dengan kata lain pada dimensi kualitas kegunaan (Usability) dan kualitas informasi (Information Quality) perlu ditingkatkan lagi

NUMERICAL MODELING OF UNSTABLE FLOWS IN CONDUCTS WITH VARIABLE GEOMETRY

Changes in the system flow of a fluid in a conduct often cause sudden changes in pressure and give rise to so-called unstable flows. So, the study of the phenomenon of unstable flows aims to determine ifthe pressure in a system is within the prescribed limits, following a perturbation of the flow. In the objective of studying the rangeof a water hammer, an examination of variations in velocity or flow and pressure resulting from inappropriate operation of the hydraulic system is made. This study presents a numerical modeling of the phenomenon of instable flows in load conducts with variable geometries. The characteristic method is used to solve the governing equations. Thanks to the AFT Impulse industrial program, very interesting and very practical numerical resultsare obtainedto describe the phenomenon of instable flows inconducts with variable geometry. And to more illustrate the graphical presentation two cases are graphically overlay for each of the two types of models (slow closing and rapid closingof the valve)

Image , optique et Vision. Étude exploratoire sur les difficultés des élèves de première au Liban

no abstractCe travail prend son origine dans une réflexion sur les objectifs de l'enseignement de la physique au Liban. Les objectifs explicites figurant dans les programmes officiels se limitent à une liste de contenus Et les objectifs implicites se limitent souvent à réussir l'un des exercices type du baccalauréat. Dans ces conditions, les concepts introduits en cours d'enseignement risquent fort de ne "fonctionner" qu'à travers un nombre particulièrement restreint de leurs propriétés. Il nous semble utile de favoriser une réflexion sur cet état de fait en amorçant un bilan des difficultés qui demeurent chez les élèves après enseignement.L'optique géométrique, contrairement à d'autres domaines tels la mécanique ou l'électricité, n'a pas fait l'objet de recherches didactiques. C'est un chapitre de la physique fort important notamment par toutes les questions pratiques auxquelles il permet d'initier les élèves. L'objectif de ce travail est donc de réaliser une exploration des difficultés liées à l'optique géométrique en classe de Première. Nous espérons avoir dégagé certaines de ces difficultés de façon suffisamment nette pour en favoriser une prise de conscience par les professeurs et les élèves, ce qui nous semble une étape indispensable vers leur solution. Nous voulons par-là contribuer à une réflexion sur la définition des objectifs d'enseignement de cette matière

NUMERICAL MODELING OF UNSTABLE FLOWS IN CONDUCTS WITH VARIABLE GEOMETRY

International audienceChanges in the system flow of a fluid in a conduct often cause sudden changes in pressure and give rise to so-called unstable flows. So, the study of the phenomenon of unstable flows aims to determine ifthe pressure in a system is within the prescribed limits, following a perturbation of the flow. In the objective of studying the rangeof a water hammer, an examination of variations in velocity or flow and pressure resulting from inappropriate operation of the hydraulic system is made. This study presents a numerical modeling of the phenomenon of instable flows in load conducts with variable geometries. The characteristic method is used to solve the governing equations. Thanks to the AFT Impulse industrial program, very interesting and very practical numerical resultsare obtainedto describe the phenomenon of instable flows inconducts with variable geometry. And to more illustrate the graphical presentation two cases are graphically overlay for each of the two types of models (slow closing and rapid closingof the valve)

KNOWLEDGE AND PERCEPTIONS TOWARDS NOVEL CORONAVIRUS (COVID-19) AMONG LEBANESE HEALTHCARE WORKERS

During the first week of March, the surge of coronavirus disease 2019 (COVID-19) cases reached over 100 countries with more than 100,000 cases. Healthcare authorities have already initiated awareness and preparedness activities beyond borders. A poor understanding of the disease among healthcare workers (HCWs) may result in delayed treatment and the rapid spread of infection. This study aimed to investigate the knowledge and perceptions of HCWs about COVID-19. A cross-sectional, web-based study was conducted among HCWs about COVID19, where a 23-item survey instrument was developed and distributed randomly to HCWs using google forms and email portals. The majority of the sample were females (75.5%) and have been working as registered nurses (50.3%), where their main source of information was their hospital and the Ministry of Health, followed by the social media the results of the study showed that the healthcare providers had adequate knowledge and positive perception regarding the prevention of COVID-19, however they have expressed concerns regarding contracting the infection and infecting family members. There has been a significant difference between those who have attended lectures and trainings and who have not on the level of the knowledge and perceptions (

THE CHALLENGES AND PROBLEMS FACED BY STUDENTS IN THE EARLY STAGE OF WRITING RESEARCH PROJECTS IN L2, UNIVERSITY OF BISHA, SAUDI ARABIA

Research, by its nature, is a critical challenging task requires in depth knowledge of the subject matter, planning, care, and hard work. From the students’ point of view, this paper attempts to explore the challenges that are faced by undergraduates when they are writing proposals and research projects at the early stages. The study target group comprised undergraduates in the final year in the College of Science and Arts, Al-Namas, University of Bisha, Saudi Arabia. Around 60 subjects participated in this study and they were from Department of English and Department of Computer Science who conducted their research projects in English as Second Language (ESL). The Research tools of the study include questionnaire and informal interviews with students and teachers of the target groups. Clearly, the results from study showed that around 70 % of the participants who are writing research or conducting research projects in English is one of the predominant challenges for them. Around 50% prefer to conduct their research in L1. The study explored various and common challenges/difficulties during writing the research proposals and projects such as: difficulty in deciding the topic for research, lack of good knowledge of the methodology, inability of finding modern, specialized and related references, lack of interest in research, lack of understanding of the subject matter, lack of time, and research guiding. The study also attempts to give some suggestions/recommendations for developing the process of writing research proposals and research projects.  Article visualizations

Mechanical Behavior of the Extraction Mud Dam for Use in the Manufacture of CEB

The aim of this work is to study the mechanical behavior of the sediments extracted from the Koudiet Meddaouar, Timgad dam (Algeria), for a possible valorization in the field for building works in order to minimize this phenomenon which is currently a concern for the operators and the persons in charge of the mobilization of the water resources. This siltation therefore severely limits its storage capacity and consequently it’s operating life. The extraction of the sediments accumulated in the dam's reservoir is therefore imperative, on the pain of seeing it perish in the medium term. These sediments are, however, of great geotechnical and mechanical value. The results of the tests conducted in the laboratory have enabled us to identify the different sediments from a physical and geotechnical point of view In front of the difficulties noted in the control of the silting up of the dams in Algeria, a very important quantity of silt being deposited annually in the dams. In order to achieve our objective, different mixtures of silt with or without lime treatment, cement glass fibers and powdered fibers were studied for the possible manufacture of Compressed Earth Bricks (CEB). The results obtained show that some of the mixtures present very interesting results in the different tests (compression and bending), verifying the conditions of the standards in force and thus allowing their use in the field of the manufacture of building materials. Doi: 10.28991/cej-2021-03091759 Full Text: PD

Strengthening of Continuous SCC Hollow Beams under Shear Stresses Using Warped CFRP Strips

The present paper is deal with shear strength evaluation of continuous self-compacting concrete hollow beams containing internal concrete ribs and externally strengthening by carbon fiber strips (CFRP). Six full-scale beam specimens and series of control specimens were tested. The adopted variables in this study are the number of internal concrete ribs and external U-shape CFRP strips at (45º). Experimental results show that the shear failure was the dominant failure for all tested beams. The cracking and ultimate load are reduced by about (19.6-30.6%) for the hollow beams specimens contains five and three ribs respectively compared with the reference beam. The ultimate load was increased for about (50.7%) for five internal ribs hollow beams strengthened by CFRP strips in compared with the same beams but without strengthening.  While, the ultimate load was increased for about (33.46%), for beam specimen who has three internal ribs and strengthened by CFRP, in comparison with the same beams but without strengthening. Keywords: CFRP Strips, Shear, Continuous Beam, Self-Compacting Concrete, Hollow, Rib

The Experimental Study On the Effectiveness of Social Media Ad Campaign: Like, Comment, Share

The popularity of social media outlets has forced us to inquire about marketing effectiveness in any area of the industry. Social media has rapidly risen in popularity as a new advertising platform that allows users to connect with one another and engage with brands.  This research has attempted to explore the attitude of people over the advertisements in what formats most people prefer to like, comment or share. We focus top trended social media sites Facebook, Twitter and LinkedIn to demonstrate the consumer engagement on advertisements placed on these sites. This research has identified the factors which influence the users to keep an eye out on advertisements that make them want to continue watching it as they spend their daily time on these social media websites and apps. To determine what makes Ads and online marketing campaigns successful we used variables such as Vividness, Content of Posts, Position of Posts, Scheduling and Call to Action.  It was conducted on 300 respondents. We used the questionnaire to collect the data and used a semantic differential scale. We questioned about the ads to respondents which were based on our variables. Results showed that our research is decisive but the variable call to action has an insignificant effect and other variables such as vividness, the position of post, the content of the post, schedule have a significant relation with customer engagement