STUDY OF RIB KNITS COURSEWISE TENSILE PROCESS

Stretchability of knitwear is one of the most important factors of wearing comfort. Elasticity of knitted structures in course wise direction is usually higher than along wales and often characterized by crosswise shrinkage. Existing methods of knitting program development do not consider the real rate of wale wise shrinkage of rib knitted structure under the course wise extension. During the study experimental research has been carried out to fulfill empirical data on the relationship between samples’ length and width under uniaxial course wise elongation. A range of samples of rib 1×1, 2×2, 3×3, 4×4 and 5×5 knits, made of cotton, bamboo, polyacrylonitrile (PAN), wool/acrylic blend and wool yarn, were stretched with a tensile machine WDW-05M. In the process of stretching the width of each specimen was defined in the moments of extension by 50, 100, 150, 200, 250 and 300 per cent. It has been found that linear approximation can be applied to describe the dependence of specimen’s width on its relative course wise elongation. It was found that the stitch height/width ratio changes unevenly. In the beginning of the process of course wise stretching of a rib knitted structure, it does exist, such an interval, where an increase of the knit’s linear size along the courses occurs without a significant shrinkage in the wale wise direction. It is suggested to name the upper limit of this interval as “unidimensional extension limit” and define it as an extension of a standard (100×50mm) specimen, at which its width decreases by 10%. It was found as well that the value of this index significantly depends on the ribbing variation and much less on the type of raw materials

FRAME MODEL OF UNIAXIAL STRETCHING OF 1x1 RIB KNITS

One of the nowadays challenges is the development of scientific sound models of knitwear deformations. The paper is devoted to developing an algorithm for constructing a frame model of rib 1x1 knits stretched in the course or wale direction. In the process of uniaxial stretching, the shape of the sample depends on the tensile forces orientation. A frame model of a deformed knitted structure, and an algorithm of construction of a mesh frame, are developed during the study. The frame model makes it possible to find coordinates of intermeshing points of every stitch. Then yarn characteristic points can be determined that, in turn, serve as input data for the construction of 3D model of rib 1x1 structure under uniaxial tensile deformations at the yarn level of detail. The study provides a graphical tool for formalization of geometric transformation that happen during 2D deformations of knitted structures, characterized by gradual change of the specimens width crosswise to the loading direction. This model is intended to become a part of a general deformation model of knitted fabrics

Personal Values as Regulators of Teacher Burnout

The aim was to identify the means of correction and prevention of burnout syndrome in college teachers who switched to online teaching during the period of quarantine caused by the COVID-19 pandemic. Descriptive and experimental research designs were used to achieve the aim. Causal relationships were defined using one-way analysis of variance (ANOVA) and correlational analysis. The Fisher’s angular transform criterion and the Mann–Whitney U test (STATISTICA 10.0) were used to determine the psychological characteristics of teachers with different levels of burnout syndrome. Boyko’s Emotional Burnout Inventory and Rokeach Value Survey (RVS) were used for diagnosis. The practical recommendations for college administrations were developed based on the causal relationships revealed in the results. It was found that the system of personal values could be an effective regulator of the personal state in difficult situations.Метою було виявлення засобів корекції та профілактики синдрому професійного вигорання у викладачів коледжу які перейшли на онлайн-навчання під час карантину, спричиненого пандемією COVID-19. Для досягнення мети використовувалися описовий та експериментальний плани дослідження. Причинно-наслідкові зв'язки були визначається за допомогою одностороннього дисперсійного аналізу (ANOVA) і кореляційного аналізу. Кутовий Фішера для визначення психологічні особливості вчителів із різним рівнем синдрому вигорання. Емоційний Бойко Для діагностики використовували інвентаризацію вигорання та опитування цінностей Рокіча (RVS). Практичний На основі виявлених причинно-наслідкових зв’язків розроблено рекомендації для адміністрацій коледжів в результатах. Виявлено, що ефективним регулятором особистості може бути система цінностей особистості стан у складних ситуаціях