Handy Ruler

When describing findings from physical examination including sizes, instead of measuring, we wrongly\ud eye-size and record inaccurate data. In order to show the rather constant measures at hand and the\ud disparity of size estimations by colleagues, we recorded size appreciation and hand measurements.\ud Sixty doctors were interviewed and asked to estimate length. Besides, their hands were measured accordingly\ud in order to check on presumed figures. All of the data was analyzed using statistic methods.\ud The results confirmed our hypothesis. Subjective estimation had a very low accuracy, ranging from\ud only 18% to 33%. The measurements of the hands showed constant figures which coincide with our\ud previous experience. This confirms our hypothesis that using our hand as a handy ruler is trustable and\ud dependable when describing or measuring distances or while planning and drawing a surgical procedure.\ud Therefore, we recommend the dependable handy ruler instead of subjective eye estimation

Динамика цен на драгоценные металлы

Приводится динамика цен на драгоценные металлы в долгосрочных и среднесрочных периодах. Показана низкая эластичность цен на золото, серебро, платину и палладий в среднесрочных и долгосрочных периодах. При сравнении стоимости драгоценных металлов в различных национальных валютах выявлено отсутствие относительного роста их цен (в долларах США) в среднесрочном периоде после 2001 г. Выявлена отрицательная зависимость цен на золото с объемами перетоков международных инвестиций

Hybrid Fabrics as Cement Matrix Reinforcement

Hybrid systems with two or more fiber materials were used to combine the benefits of each fiber into a single composite product. Strength and toughness optimization of hybrid thin sheet composites has been studied extensively using combination of different fiber types with low and high modulus of elasticity. Hybrid reinforcement is more significant when the reinforcing structure is in fabric geometry. Fabric structure provides full control on the exact location of each yarn and its orientation in the composite during production, thus maximizes the reinforcing efficiency. A high-strength, high-modulus fiber primarily tends to increase the composite strength with nominal improvements in toughness. A low-modulus fiber expected to mainly improve toughness and ductility. Combination of two or more types of fiber can produce a composite that is both strong and tough as compared to a mono fiber composite. The purpose of the current work was to study hybrid warp knitted fabrics as reinforcement for cementbased composite, having AR (Alkali Resistance) glass and Polypropylene (PP) as the reinforcing yarns. The examined ratios between the two different yarns were 0:100, 25:75, 50:50, 75:25, 100:0 (glass: PP, by percentage). It was found that in the hybrid system, the fracture mechanism is a superposition of the mono systems, and the tensile behavior is a combination between the two materials

Hybrid fabrics as cement matrix reinforcement

Hybrid systems with two or more fiber materials were used to combine the benefits of each fiber into a single composite product. Strength and toughness optimization of hybrid thin sheet composites has been studied extensively using combination of different fiber types with low and high modulus of elasticity. Hybrid reinforcement is more significant when the reinforcing structure is in fabric geometry. Fabric structure provides full control on the exact location of each yarn and its orientation in the composite during production, thus maximizes the reinforcing efficiency. A high-strength, high-modulus fiber primarily tends to increase the composite strength with nominal improvements in toughness. A low-modulus fiber expected to mainly improve toughness and ductility. Combination of two or more types of fiber can produce a composite that is both strong and tough as compared to a mono fiber composite. The purpose of the current work was to study hybrid warp knitted fabrics as reinforcement for cementbased composite, having AR (Alkali Resistance) glass and Polypropylene (PP) as the reinforcing yarns. The examined ratios between the two different yarns were 0:100, 25:75, 50:50, 75:25, 100:0 (glass: PP, by percentage). It was found that in the hybrid system, the fracture mechanism is a superposition of the mono systems, and the tensile behavior is a combination between the two materials