In this research, a variable stiffness actuator is proposed to enhance the damping of the mechanical vibrating system. The frequency response analysis of the vibrating system is dependant in order to analyze and synthesis this semi-active damping, where the suggested process is using active filter to estimate the present frequency of the vibration system, and this will limit the value of the stiffness of the vibrated system. Two active filter s are needed, low-pass-filter (LPF) to choose the higher stiffness of the actuator at small frequencies as well as more damping and high-pass-filter (HPF) to choose the lower stiffness of the actuator at high frequencies as well as more damping, and so

Background: The final stage of endodontic therapy is complete obturation of the root canal system to provide as perfect as possible at the cementodentinal junction of the apical foramen. The purpose of this in vitro study was to evaluate the sealing ability of injection molded thermoplasticized gutta percha and lateral condensation techniques with and without the use of sealers. Materials and Methods: Forty freshly extracted adult human maxillary central incisors with complete formed apices were utilized in this study. The teeth were randomly divided into four groups for evaluation of the apical seal. Group (1) lateral condensation gutta percha technique without sealer, (2) lateral condensation gutta percha technique with sealer, (3) Inject

The present research aims at identifying the educational problems and psychological problems of distinguished students at the intermediate level. The research sample consists of (246) students who are randomly selected from four distinguished schools (2) in the Karkh\1 and (2) in the Rusafa\2.

The researcher has constructed two scales for measuring the educational and psychological problems. She ensures the psychometric characteristics of the two scales. Alph-Cronbach and test-retest methodsare used to ensure reliability. Some statistical treatments are used to find out the aims of research. These treatments include the one-sample T-test, two independent samples T-test, and the Pearson correlation coefficient. The results show th

Arabian Political Regimes: Problems of Policies and Rule; An Introduction to Interpreting (The Arabian Spring) The Arab Region witnessed, since 2011, critical changes overthrew a group of Arab regimes in some of its countries, and the reaction of these changes are still going on up to now. These changes were given lots of justifications and interpretations. The current study tries to concentrate on the most important problems which were due to what was known as (The Arab Spring). The study proposes that the crisis which the countries of the area are exposed to is not spontaneous in many of its aspects. It is totally a crisis of rule and policies. Because it is a reflection of the nature of authority in the Arabian regimes on the one hand

The research aims to study the administrative problems in the sports management of the members of the administrative bodies of the first-class clubs of the province of Baghdad in football. The researchers used the descriptive approach (survey study) for its relevance to the nature of the research. The research community is represented by first-class football players, who numbered (176) players. The research sample was chosen by the deliberate method, as the basic research sample reached (136) individuals from the total research community. The researchers used the questionnaire to collect the necessary data to achieve the goal of the research by applying a questionnaire that aims to ident

The early childhood stage, which is usually described as establishing the development and growth of most of the child’s mental, psychological, moral, and physical abilities, so scientists and researchers have been interested in the growth and upbringing of the child, especially for the specified period between (6 until the age of 11) due to the importance of education in this stage. The age stage in terms of developing the child’s senses and experiences, because he is by nature inclined to play and draw in his instinctive activity, according to which his natural responses to stimuli and his contemplation of what surrounds him change. Since drawing plays an important role in raising a child from an emotional and intellectual point of vie

ان الغرض من هذا البحث هو المزج بين القيود الضبابية والاحتمالية. كما يهدف الى مناقشة اكثر حالات مشكلات البرمجة الضبابية شيوعا وهي عندما تكون المشكلة الضبابية تتبع دالة الانتماء مرة دالة الاتنماء المثلثية مرة اخرى، من خلال التطبيق العملي والتجريبي. فضلا عن توظيف البرمجة الخطية الضبابية في معالجة مشكلات تخطيط وجدولة الإنتاج لشركة العراق لصناعة الأثاث، وكذلك تم استخدام الطرائق الكمية للتنبؤ بالطلب واعتماده

Background: Conventional  MR imaging is essential for diagnosis and evaluation of the posterior fossa tumors  Objectives: To assess the value of diffusion weighted imaging and apparent diffusion coefficient in making distinction between different histological types of posterior fossa tumors.

Type of the study: Cross-sectional study.

Methods: Brain MRI and DWI assessed 19 patients (12 female and 7 male) with MRI diagnosis of posterior fossa tumors. absolute ADC values of contrast -enhancing solid tumor region and ADC ratio of solid tumor to ADC of normal -appearing deep White matter were compared with histological diagnosis postoperatively .The m

The study of cohomology groups is one of the most intensive and exciting researches that arises from algebraic topology. Particularly, the dimension of cohomology groups is a highly useful invariant which plays a rigorous role in the geometric classification of associative algebras. This work focuses on the applications of low dimensional cohomology groups. In this regards, the cohomology groups of degree zero and degree one of nilpotent associative algebras in dimension four are described in matrix form.