Upgrade capacity scenarios enabled by multi-band optical systems

The ITU-G.652D is the most deployed optical fiber worldwide and presents a wide low-loss window with negligible water absorption peak. Multi-band systems exploit this characteristic to increase the transmission capacity. In this work, we show the optical degradation in terms of generalized signal-to-noise ratio, on different bands, resulting from successive channel upgrades until the complete low-loss window is occupied

To Cloud or not to Cloud: A Qualitative Study on Self-Hosters’ Motivation, Operation, and Security Mindset

Despite readily available cloud services, some people decide to self-host internal or external services for themselves or their organization. In doing so, a broad spectrum of commercial, institutional, and private self-hosters take responsibility for their data, security, and reliability of their operations. Currently, little is known about what motivates these self- hosters, how they operate and secure their services, and which challenges they face. To improve the understanding of self-hosters’ security mindsets and practices, we conducted a largescale survey (NS=994) with users of a popular self-hosting suite and in-depth follow-up interviews with selected commercial, non-profit, and private users (NI =41). We found exemplary behavior in all user groups; however, we also found a significant part of self-hosters who approach security in an unstructured way, regardless of social or organizational embeddedness. Vague catch-all concepts such as firewalls and backups dominate the landscape, without proper reflection on the threats they help mitigate. At times, self-hosters engage in creative tactics to compensate for a potential lack of expertise or experience

A semi-automated security advisory system to resist cyber-attack in social networks

Social networking sites often witness various types of social engineering (SE) attacks. Yet, limited research has addressed the most severe types of social engineering in social networks (SNs). The present study investigates the extent to which people respond differently to different types of attack in a social network context and how we can segment users based on their vulnerability. In turn, this leads to the prospect of a personalised security advisory system. 316 participants have completed an online-questionnaire that includes a scenario-based experiment. The study result reveals that people respond to cyber-attacks differently based on their demographics. Furthermore, people’s competence, social network experience, and their limited connections with strangers in social networks can decrease their likelihood of falling victim to some types of attacks more than others

Maternal and offspring intelligence in relation to BMI across childhood and adolescence

Objective: The present study tested the association between both mothers’ and offspring’s intelligence and offspring’s body mass index (BMI) in youth. Method: Participants were members of the National Longitudinal Survey of Youth 1979 (NLSY-79) Children and Young Adults cohort (n = 11,512) and their biological mothers who were members of the NLSY-79 (n = 4932). Offspring’s IQ was measured with the Peabody Individual Achievement Test (PIAT). Mothers’ IQ was measured with the Armed Forces Qualification Test (AFQT). A series of regression analyses tested the association between IQ and offspring’s BMI by age group, while adjusting for pre-pregnancy BMI and family SES. The analyses were stratified by sex and ethnicity (non-Black and non-Hispanic, Black, and Hispanic). Results: The following associations were observed in the fully adjusted analyses. For the non-Blacks and non-Hispanics, a SD increment in mothers’ IQ was negatively associated with daughters’ BMI across all age-groups, ranging from β = −0.12 (95% CI −0.22 to −0.02, p = 0.021) in late childhood, to β = −0.17 (95% C.I. −0.27 to −0.07, p = 0001), in early adolescence and a SD increment in boys’ IQ was positively associated with their BMI in early adolescence β = 0.09 (95% CI 0.01–0.18, p = 0.031). For Blacks, there was a non-linear relationship between mothers’ IQ and daughters’ BMI across childhood and between girls’ IQ and BMI across adolescence. There was a positive association between mothers’ IQ and sons’ BMI in early adolescence (β = 0.17, 95% CI 0.02–0.32, p = 0.030). For Hispanic boys, there was a positive IQ-BMI association in late childhood (β = 0.19, 95% CI 0.05–0.33, p = 0.008) and early adolescence (β = 0.17, 95% CI 0.04–0.31, p = 0.014). Conclusion: Mothers’ IQ and offspring’s IQ were associated with offspring’s BMI. The relationships varied in direction and strength across ethnicity, age group and sex. Obesity interventions may benefit from acknowledging the heterogeneous influence that intelligence has on childhood BMI

Impact resistance bio compound

Modified wood fibre reinforced polypropylene composites at a wood fibre content of 50 wt. % are prepared using different types of wood fibres (beech wood refiner fibre, mercerised beech wood refiner fibre, mercerised and bleached beech wood refiner fibre as well as beech wood chips, mercerised beech wood chips, mercerised and bleached beech wood chips) to improve the impact resistance of the final composite. Additionally a beech wood refiner fibre-PP composite as well as a beech wood chip-PP composite are mixed with regenerated cellulosic fibres (5 wt. % and 10 wt. %) to further enhance the impact resistance. To increase the interfacial adhesion with the matrix and to improve the dispersion of particles two different coupling agents with contents from 2 wt. % to 8 wt. % are tested with two wood plastic composites (WPC). One is made of beech wood refiner fibres and the other one is produced from beech wood chips. The present study investigated Charpy impact property of wood fibres reinforced polypropylene as a function of fibre modification, content of regenerated cellulosic fibres and coupling agent. From the results it is observed that beech wood refiner fibre-PP composites show better Charpy impact properties than beech wood chips-PP composites. Charpy impact resistance is improved by mixing regenerated cellulose fibres (RCF) and RCF-PP-granule with beech wood refiner fibres and chips. The maximum increase in impact resistance is two times for refiner fibres and 10 % RCF-PP-granule respectively three and a half times for chips and 10 % RCF-PP-granule. By adding coupling agent Charpy impact resistance is nearly doubled for all wood fibre-PP composites

Einsatz von faserverstärkten Kunststoffen für tragende Baukonstruktionen

Der Mensch suchte schon immer nach Materialien, die er zur Umsetzung seiner Ideen und nach seinen Ansprüchen einsetzen kann. Die Entwicklung des Bauwesens ist daher eng verknüpft mit der Entwicklung der Baustoffe. Faserverstärkte Kunststoffe kamen Mitte des 20. Jahrhunderts als eine eigenständige Baustoffgruppe in das Bauwesen. Sie ermöglichten die Realisierung von Flächentragwerken und Sandwich-konstruktionen des Leichtbaus, die Realisierung von Traumgebilden, die dünnwandig über weite Strecken spannen, Blumen- und Kristallgebilde, die uns Menschen eine neuartige Schutzhülle, eine Behausung sind. Faserverstärkte Kunststoffe sind eine weit gefasste Baustoffgruppe, da verschiedenste Faserarten neben Tausenden von Kombinationen der Kunststoffe gemeinsam neue leistungsfähige Werkstoffe bilden. Die Kunststoffe befinden sich heute in einer Umbruchphase. Nicht mehr allein das Erdöl dient als Basis zur Produktion der Plasten, sondern auch Naturprodukte werden chemischen Prozessen unterworfen und als Biokunststoffe angeboten. Naturfasern verlassen ihren angestammten Platz als Textilgewebe der Kleidungs- oder Teppichindustrie. Das hier vorgestellte, sich in der Entwicklung befindliche Bausystem, basiert auf dem Zusammenspiel von neuem Materialverbund, vorhandenen Erkenntnissen des Leichtbaus durch Sandwichsysteme und aktuellen nachhaltigen ressourcen- und energiesparenden Bauweisen