Analysis of the development of drifting ice formations impact on marine facilities assessment methods

The high resource potential of the Arctic determines the active exploration and development of these territories, in particular the Arctic continental shelf. The development of offshore fields is directly related to the issues of marine communications construction and operation in freezing waters. They are associated with minimization of environmental risks, reducing the cost of construction work, and ensuring reliable operation of underwater systems. The ice loads, especially, loads from ice gouging are considered one of the most significant loading conditions for such systems. Deformations of the soil around the pipeline during gouging may cause unacceptable deformations as a result of bending, which may lead to emergency situations. The article discusses the main features of ice gouging and the development of research and assessment methods for ice gouging impact on offshore pipelines. The article also provides the analysis of the research methods, their applications and limitations, and points out further research directions.

Adhesion Strength of Al/Epoxy Resin Interface over a Wide Range of Loading Rates

This study evaluated the interfacial adhesive strength between aluminium alloy and epoxy resin (Al/epoxy resin) over a wide range of strain rates (loading rates). We conducted three types of tests with different loading rate, i.e., a quasi-static tensile test for the range of lower loading rate, a Split Hopkinson Bar (SHB) for the range of middle loading rate, and Laser Shock Adhesion Test (LaSAT) for the range of higher loading rate. LaSAT is a unique test of adhesion evaluation, since laser induced shock wave is employed to lead interfacial fracture. In parallel, finite element method (FEM) is conducted in order to calculate stress distribution at the interface during LaSAT. As a result, it was found that the interface between the aluminium alloy and the epoxy resin interface shows significant loading rate dependency of the adhesion strength and this tendency is very similar to that of bulk epoxy materials.

Effects of ZIF-8 MOFs on structure and function of blood components

ZIF-8 MOFs, with their large specific surface area and void volume, unique biodegradability and pH sensitivity, and significant loading capacity, have been widely used as carrier materials for bioactive molecules such as drugs, vaccines and genes.

Modeling and Design Optimization of Robotic Hoses for 3D Printing of Cement

Modeling tendon tensions for applications of tendon-actuated continuum robots under significant loading is necessary for sizing motors, tendons, and other components to ensure that the robot can safely support its mass during operation. While models exist that express tendon tensions as a function of continuum robot configuration, previously proposed models do not consider the effects of gravity on tendon tensions. In this paper, we discuss the addition of gravity to a static model previously developed for low-mass tendon-actuated continuum robots. Using the Euler-Lagrange methodology, the potential energy due to gravity is incorporated into the formulation of the equations that describe tendon tensions as a function of robot configuration. Preliminary experimental results reveal the potential of this nonzero-gravity tendon-tension model.

Design and Test of an Articulation Mechanism for a Morphing Missile Nosecone

This paper covers the design and development of a mechanism to change the angle of an air-to-air missile nosecone relative to the missile body while in flight. A group of senior cadets at the United States Air Force Academy performed the work in fulfillment of requirements for their capstone design project. The Air Force Research Laboratory (AFRL) sponsored the project and provided a set of requirements to guide the design. These requirements include the challenge of torque transfer under significant loading in order to drive the nosecone to a new angle. The report will cover significant design changes from last year’s design and the justification for these changes. A complete sub-system breakdown follows. Finally, the planned testing and evaluation of the design is discussed.

Protecting against Website Fingerprinting with Multihoming

Anonymous communication tools, such as Tor, are extensively employed by users who want to keep their web activity private. But recent works have shown that when a local, passive adversary observes nothing more than the timestamp, size and direction (incoming or outgoing) of the packets, it can still identify with high accuracy the website accessed by a user. Several defenses against these website fingerprinting attacks have been proposed but they come at the cost of a significant overhead in traffic and/or website loading time. We propose a defense against website fingerprinting which exploits multihoming, where a user can access the Internet by sending the traffic through multiple networks. With multihoming, it is possible to protect against website fingerprinting by splitting traffic among the networks, i.e., by removing packets from one network and sending them through another, whereas current defenses can only add packets. This enables us to design a defense with no traffic overhead that, as we show through extensive experimentation against state-of-the-art attacks, reaches the same level of privacy as the best existing practical defenses. We describe and evaluate a proof-ofconcept implementation of our defense and show that is does not add significant loading-time overhead. Our solution is compatible with other state-of-the-art defenses, and we show that combining it with another defense further improves privacy.

Validation of a childhood eating disorder outcome scale

We developed and validated a childhood eating disorder outcome scale based on outcomes associated with body mass index standard deviation score (BMI-SDS). This prospective observational study included 131 children with eating disorders (aged 5–15 years). Participants’ outcomes scales were completed at the first visit and at 1, 3, 6, and 12 months. The scale evaluated 12 outcomes: body weight change (BW), eating attitude (EA), fear of being fat (FF), body image distortion (BD), menstruation (ME), perceived physical condition (PC), attending school (AS), disease recognition by school (RS), family function (FA), disease recognition by parent (RP), social adaptation (SA), and relationships with friends (RF). Responses to all items were on a four-point Likert scale. Exploratory factor analysis was used to determine the number of factors based on the 12 outcomes. The relation between outcome scale scores and BMI-SDS over the 12-month follow-up period was analyzed. Two types of factors were extracted: disease-specific factors (EA, FF, BD) and biopsychosocial factors (BW, PC, AS, FA, SA, RF). Three items (ME, RS, RP) were excluded because they showed no significant loading effect. There was a significant negative correlation between the outcome scale and BMI-SDS, and changes in outcome scale scores from baseline to 12 months were significantly associated with improvement in BMI-SDS. We developed a childhood eating disorder outcome scale characterized by disease-specific and biopsychosocial factors. Biopsychosocial management combined with a therapeutic approach for disease-specific symptoms may support body weight recovery for children with eating disorders.

Fluorine-donating electrolytes enable highly reversible 5-V-class Li metal batteries

Lithium metal has gravimetric capacity ∼10× that of graphite which incentivizes rechargeable Li metal batteries (RLMB) development. A key factor that limits practical use of RLMB is morphological instability of Li metal anode upon electrodeposition, reflected by the uncontrolled area growth of solid–electrolyte interphase that traps cyclable Li, quantified by the Coulombic inefficiency (CI). Here we show that CI decreases approximately exponentially with increasing donatable fluorine concentration of the electrolyte. By using up to 7 m of Li bis(fluorosulfonyl)imide in fluoroethylene carbonate, where both the solvent and the salt donate F, we can significantly suppress anode porosity and improve the Coulombic efficiency to 99.64%. The electrolyte demonstrates excellent compatibility with 5-V LiNi0.5Mn1.5O4 cathode and Al current collector beyond 5 V. As a result, an RLMB full cell with only 1.4× excess lithium as the anode was demonstrated to cycle above 130 times, at industrially significant loading of 1.83 mAh/cm2 and 0.36 C. This is attributed to the formation of a protective LiF nanolayer, which has a wide bandgap, high surface energy, and small Burgers vector, making it ductile at room temperature and less likely to rupture in electrodeposition.

Developing Entrepreneurial Intensity among Women Entrepreneurs of Jammu & Kashmir: Model Building through Confirmatory Factor Analysis

In developing nations like India, entrepreneurship can be a solution of many economy-related problems; to achieve this, high level of entrepreneurial intensity (EI) is to be ensured. EI measures the focus and commitment of an entrepreneur towards his/her venture. It can influence performance of firms, provide sustainable advantage to individuals, societies etc. The state of Jammu and Kashmir (J&K) is facing issues like low GDP and high unemployment. High level of EI, especially among women, can provide solution to many of its problems. So, the present endeavour assesses the level of intensity among the women entrepreneurs and then suggests some measures to enhance the same. The results of the study show that innovativeness, pro-activeness, risk-taking, competitive aggressiveness and autonomy, which are taken as the basic postulates of EI in study, show significant loading. Although women entrepreneurs tend to show pro-activeness and competitive aggressiveness strongly, it is innovativeness, risk-taking and autonomy are not good fit. This study proposes a model for training for the women entrepreneurs to improve their level of EI to accelerate the growth of entrepreneurship in the state. This will in turn enhance the overall economic growth of the state.

Structural Equation Modelling applied to proposed Statistics Attitudes-Outcomes Model: A case of a University in South Africa

The purpose of the study is to investigate the structural relationships among constructs of the statistics attitudes-outcomes model (SA-OM) using exploratory structural equation modelling (ESEM) methodology. The sample consists of 583 first-year undergraduate students enrolled for statistics courses at the university in South Africa. ESEM reveal that all but two of the nine constructs have well to excellent reliability. To enhance the model, we deleted the eight variables. All other indicators have a significant loading into a construct. Congruency of the SA-OM and expectancy value model (EVM) is noted. The SRMR for all modified models are less than 0.10 suggesting that all these models have acceptable fit. Moreover, all the modified models have RMSE values within the ranges of adequate fit. On the contrary, all the models have unacceptable fit according to PCF, CFI, AGFI and PGFI statistics, i.e. according to all parsimony fit indices except the RMSE. The results also reveal that all incremental fit indices but the BBNFI approve the modified models as acceptable since most of these indices are almost equal to a cut-off point of 0.9. However, BBNNI disapprove the ML3 and ML5 models as being acceptable. A host of inconsistencies in fit indices are noted.