A Near-Optimal Decentralized Servomechanism Controller for Hierarchical Interconnected Systems

This paper is concerned with decentralized output regulation of hierarchical systems subject to input and output disturbances. It is assumed that the disturbance can be represented as the output of an autonomous LTI system with unknown initial state. The primary objective is to design a decentralized controller with the property that not only does it reject the degrading effect of the disturbance on the output (for a satisfactory steady-state performance), it also results in a small LQ cost function (implying a good transient behavior). To this end, the underlying problem is treated in two phases. In the first step, a number of modified systems are defined in terms of the original system. The problem of designing a LQ centralized controller which stabilizes all the modified systems and rejects the disturbance in the original system is considered, and it is shown that this centralized controller can be efficiently found by solving a LMI problem. In the second step, a method recently presented in the literature is exploited to decentralize the designed centralized controller. It is proved that the obtained controller satisfies the pre-determined design specifications including disturbance rejection. Simulation results elucidate the efficacy of the proposed control law

Systematic Error Detection in Laboratory Medicine

Measurements in laboratory medicine have a degree of uncertainty; this uncertainty is often called “error” and refers to imprecisions and inaccuracies in measurement. This measurement error refers to the difference between the true value of the measured sample and the measured value. One of the types of error is systematic error, also called bias, because these errors errors are reproducible and skew the results consistently in the same direction. A common approach to identify systematic error is to use control samples with a method comparison approach. An alternative is use of statistical methods that analyze actual patient values either as an “Average of Normals” or a “Moving Patient Averages.” Fundamental questions should be decided before a quality control method is used: how are weights assigned to the results? Is preference given to more recent samples or to the older samples? How sensitive should the model be? In this chapter, we will expand the fundamental notion of systematic error and explain why it is difficult to identify and measure and current statistical methods that are used to detect systematic error or bias

Split calvarial graft and titanium mesh for reconstruction of post-craniotomy frontal bone defect

Background: The goal of cranioplasty is to achieve a lifelong, stable and structural reconstruction of the cranium covered by a healthy skin and scalp flap. We present two cases of large frontal bone defect following a accident..Cases: We describe the utilization of autogenous local split calvarial graft and titanium mesh for the reconstruction of the post trauma frontal bone defect.Conclusion: Cranioplasty using split calvarial bone grafting for restoring large cranial defects resulting from a trauma is a useful technique, and allows the surgeon to reconstruct a moderate to large cranial defect without rifting the inner cortical plate.Keywords: Bone Graft; Calvarial Splitting; Cranioplast

Effect of concrete properties and prestressing steel indentation types on the development length and flexural capacity of pretensioned concrete members

Doctor of PhilosophyCivil EngineeringRobert J. PetermanA study was conducted to determine the effect of different concrete properties and prestressing steel indentation types on development length and flexural capacity of pretensioned members. Wires and strands commonly used in the manufacturing of prestressed concrete railroad ties worldwide were selected for the study. Thirteen different 5.32-mm-diameter prestressing wire types and six different strands (four, seven-wire strands and two, three-wire strands) were used to cast prisms with a square cross section. The ratio of concrete to prestressed steel in the test prism’s cross section was representable of typical concrete railroad ties. Thus, geometrical and mechanical properties of test prisms were representative of actual ties in the railroad industry. To understand the effect of concrete-release strengths and slumps on development length, all parameters were kept constant in the prisms except concrete-release strength and slump. To manufacture prisms with different release strengths, all four wires/strands were pulled and detensioned gradually when the concrete compressive strength reached 3500 (24.13 MPa), 4500 (31.03 MPa), and 6000 (41.37 MPa) psi. To determine the effect of different slumps on development length, prisms with different slumps of 3 in. (7.6 cm), 6 in. (15.2 cm), and 9 in. (22.9 cm) were manufactured and all other parameters were kept constant in prisms. All prisms were tested in three-point bending at different spans to obtain estimations of development length based on type of reinforcement, concrete-release strength, and concrete slump. Lastly, a design equation was developed based on experimental data for prediction of development length. In the last phase of load tests, cyclic-loading tests were conducted on the prisms manufactured with wires to evaluate the bond performance of wires with different indentation types under cyclic loading. A total of 210 load tests, including 14 cyclic tests, were conducted. The monotonic-load tests revealed a large difference in the development length of pretensioned concrete members manufactured with different wire/strand types and different concrete-release strengths. Also, the cyclic-load tests revealed a significant difference in bond performance of different wire types under cyclic loading compared to monotonic loading

Sufficient conditions for the convergence of a class of nonlinear distributed consensus algorithms

This paper is concerned with the convergence of a class of continuous-time nonlinear consensus algorithms for single integrator agents. In the consensus algorithms studied here, the control input of each agent is assumed to be a state-dependent combination of the relative positions of its neighbors in the information flow graph. Using a novel approach based on the smallest order of the nonzero derivative, it is shown that under some mild conditions the convex hull of the agents has a contracting property. A set-valued LaSalle-like approach is subsequently employed to show the convergence of the agents to a common point. The results are shown to be more general than the ones reported in the literature in some cases. An illustrative example demonstrates how the proposed convergence conditions can be verifie

Predictors of hypoglycemia fear in patients with type 2 diabetes under treatment of oral anti hyperglycemic agents

Introduction: Hypoglycemia is a medical emergency that disrupt routine life. Hypoglycemia experience likely causes fear of its recurrence. Even mild or moderate episodes may worry patients for frequent events. Limited studies have assessed predictors offear of hypoglycemia in patients with diabetes. The aim of the present study was to determine the predicting factors of hypoglycemia in type 2 diabetic patients treated with oral anti-hyperglycemic agents. Materials and Methods: This cross-sectional study was conducted on 357 patients with type 2 diabetes treated with oral anti-diabetic drugs. Data was collected through interviews by using a three-part questionnaire (socio-demographic & clinical characteristics, HFS-II). The data was analyzed with descriptive and deductive statistic methods (Generalized Linear Models) at 5<0.05 using SPSSv.16 software. Results: Mean age of patients was 54.11±11.54 years and the majority were female (56.6%). The mean HFS score was 16.8±16.33. In regression analysis, frequency of hospitalization (p<0.001), employment (p<0.048), number of medications (p<0.029), hyperlipidemia (p<0.026), hypoglycemia (p<0.001) and hypoglycemia intensity (p<0.001) were related to fear of hypoglycemia. Conclusion: According to the results of the present study, hypoglycemia and its intensity are considered as the strongest predictors of fear of hypoglycemia. Therefore, prevention of hypoglycemia occurrence and reduction of its related fear can be performed by modifying the other predictors identified in this study. Keywords: Fear of hypoglycemia, Diabetes Mellitus, Oral anti-hyperglycemic agent

Investigation the Dysfunctional attitudes and its´ relationship with stress, anxiety and depression in breast cancer patients

Background: Breast cancer is considered as the most common as well as most effective malignancy in adult female population, has leaded to deep psychological and emotional problems such as depression, anxiety and stress. One of the possible factors lead to develop of depression, anxiety and stress in people based on cognitive models, is the cognitive distortions and dysfunctional attitudes towards the situation. The components included high prevalence and huge effects of breast cancer´s depression, anxiety and stress on different aspect as well as key role of dysfunctional attitudes in development of these elements; encouraged us to design and perform a study with aim to investigation the dysfunctional attitudes and its´ relationship with stress, anxiety and depression in breast cancer patients referred to a specialized cancer hospital Isfahan, Iran. Methods: This descriptive, analytic cross sectional study was conducted on cancer patients who were selected using simple sampling. A total number of 297 hospitalized patients with breast cancer were enrolled in 6 months. The clinical and demographic characteristics information, dysfunctional attitudes questionnaire (DAS-26) and the depression, anxiety, and stress scale (DASS-42) were used. All analyses were performed with descriptive and analytic statistical methods in SPSS for Windows 18.0 (SPSS Inc., Chicago, IL, USA). Findings: Mean scores of dysfunctional attitudes were 87.35 (27.53). Also mean scores of stress, anxiety and depression were 14.16 (9.38), 11.64 (8.27) and 12.06 (9.52) relatively. Based on study findings there was a statistically significant relationship between dysfunctional attitudes with stress, anxiety and depression in patients with breast cancer. Conclusion: With regard to results of this study, breast cancer patients with higher scores dysfunctional attitudes had more stress, anxiety and depression. In addition low dysfunctional attitudes score was an important protecting factor against stress, anxiety and depression in these patients

Environmental Impact Assessment of the Industrial Estate Development Plan with the Geographical Information System and Matrix Methods

Background. The purpose of this study is environmental impact assessment of the industrial estate development planning. Methods. This cross-sectional study was conducted in 2010 in Isfahan province, Iran. GIS and matrix methods were applied. Data analysis was done to identify the current situation of the region, zoning vulnerable areas, and scoping the region. Quantitative evaluation was done by using matrix of Wooten and Rau. Results. The net score for impact of industrial units operation on air quality of the project area was (−3). According to the transition of industrial estate pollutants, residential places located in the radius of 2500 meters of the city were expected to be affected more. The net score for impact of construction of industrial units on plant species of the project area was (−2). Environmental protected areas were not affected by the air and soil pollutants because of their distance from industrial estate. Conclusion. Positive effects of project activities outweigh the drawbacks and the sum scores allocated to the project activities on environmental factor was (+37). Totally it does not have detrimental effects on the environment and residential neighborhood. EIA should be considered as an anticipatory, participatory environmental management tool before determining a plan application