Observer Design Approach Research Articles

The Bigger Level Of Blood Lead, The Higher Level Of SGOT and SGPT In Residents Around The Used Battery Recycling Industry

Hazardous materials that need to be watched out for are exposure to lead (Pb) in solder wire from the used battery recycling industry. Pb can cause health problems for workers and the community around the high risk industry. Exposure occurs through inhalation, ingestion or skin because Pb is a multi-media pollutant. Abnormal levels of Pb in the blood have a risk of 1,783 times, can reach toxic levels and cause disturbances in the soft tissues of the liver, characterized by increased levels of SGOT and SGPT in the blood. The purpose of this study was to determine the relationship between blood lead levels and SGOT & SGPT levels in residents around the used battery recycling industry. The number of research samples as many as 40 respondents through the analytical method of observational cross-sectional design approach. Sampling was done by non-probability sampling with purposed sampling technique. The results showed that Pb levels reached 695.90 ug/L exceeds the value of the biological exposure index (IPB). There is a relationship between blood lead levels and blood SGOT& SGPT levels (p = 0.003) and (p = 0.000) with a strong positive relationship (r = 0.460)and (r = 0.526). The conclusion is that there is a relationship between blood lead levels and SGOT & SGPT levels in residents around the used battery recycling industry and the greater the blood Pb level, the higher the SGOT & SGPT levels.

Data-Driven Observer Design for an Inertia Wheel Pendulum with Static Friction

An indirect data-driven state observer design approach for the inertia wheel pendulum considering static friction of the actuated inertia disc is presented. The frictional forces occurring in a real laboratory setup are characterized by the Stribeck effect as well as the transition between two different dynamic behaviors, sticking and non-sticking. These switching nonlinear dynamics are identified with various machine learning methodologies in a data-driven manner, i.e., the unsupervised separation and feature clustering of measured state trajectories into two dynamic classes, and the supervised classification of a state-dependent switching condition. The identified system with the interior switching-structure of two dynamics is combined with a moving horizon estimator.

Discrete-time LPV Systems with Inexact Scheduling Parameters: an Unknown Input Observer Design approach

In this paper, a novel unknown input observer (UIO) design for discrete-time linear parameter-varying (LPV) with inexact scheduling parameters is addressed. The proposed approach is particularly relevant as most LPV design conditions require that the time-varying parameters of the system are completely known and real-time available. Therefore, such strategies do not present adequate formulations to deal with such types of uncertainty. Moreover, UIOs have significant applications in different areas, such as fault detection and isolation problems. Existence conditions for the UIO are provided in order to properly handle the mismatch along with the presence of unknown inputs in the LPV system. The design conditions are based on an input-to-state stability approach obtained from a parameter-dependent Lyapunov function and are cast in the form of Linear Matrix Inequalities. The effectiveness of the proposed methods is illustrated using a numerical example.

Set-membership state estimators based on cooperative output injections

To estimate validated bounds on the actual state vector of uncertain non-linear systems, cooperative output injections methods are proposed in this contribution. The aim of the output injections is to design set-membership state estimators that ensure the order-preserving property between the lower, actual and upper state trajectories. Based on a special sensors placement, continuous-time and event-triggered output injections are proposed to cope with the conservatism of the classical bounding system methods. Furthermore, based on some properties of monotone dynamical systems, the convergence of the proposed set-membership state estimators is shown. It is worth pointing out that the proposed set-membership state estimation method allows one: on one hand, to avoid the conservatism related to the use of similarity transformations usually required in the framework of interval observer design approaches, and on the other hand, to circumvent the pessimism accumulation related to the wrapping effect of set-valued iterative numerical schemes.

Output-Feedback Speed-Tracking Control Without Current Feedback for BLDCMs Based on Active-Damping and Invariant Surface Approach

With the proposed technique, a controlled brushless DC motor can robustly track the desired trajectory, while estimating angular acceleration, to remove current feedback. The controller design task does not require true motor parameters and load information using the standard disturbance observer design approach. The first feature is that a parameter-independent angular acceleration observer is devised to avoid direct differentiation of the speed measurement. The second one is that active-damping pole-zero cancellation control stabilizes the surface, thereby describing the desired first-order tracking system dynamics. The prototype 50-W BLDCM control system experimentally evaluates the speed-tracking and positioning performances.

Fault-Tolerant Quantized Sliding Mode Observers Design for a Class of Takagi-Sugeno Fuzzy System With Unmeasurable Premise Variable

This article addresses the state and fault estimation problems for a class of quantized Takagi–Sugeno (T-S) fuzzy systems with sensor and actuator faults. Two types of observer design methods are developed for two different network transmission environments. In the first case, the signal quantization effect is only considered on the channel between sensor and controller, and a sliding mode observer is designed, which can reconstruct the actuator faults. In the second case, the quantization effects are considered in both the sensor-controller side and the controller-actuator side, which is more difficult to be dealt with compared to the first case, and the sliding mode observer method cannot be effective now since the discontinuous term is difficult to be designed. A descriptor reduced-order observer is presented to solve this problem, where the jumping behavior that resulted from the signal quantization is considered in the observer, which is novel and effective to compensate the quantization effects. Finally, simulation examples of rigid-body satellite attitude control T-S fuzzy system are presented to verify the effectiveness of the proposed observer design approaches.

An algebraic, distributed state observer for continuous‐ and discrete‐time linear time‐invariant systems with time‐varying communication graphs

SummaryIn this paper we address the problem of distributed state estimation of continuous‐ and discrete‐time stable, LTI systems. The classical observer canonical form representation of the system dynamics is used to identify the observable states for each node (agent). The main novelty of our contribution is to obviate the need of the asymptotically (or finite‐time) local Luenberger observers. Instead, following the generalized parameter estimation‐based observer design approach, we use the state transition matrix of the system to translate the problem of reconstruction of the observable states into one of parameter estimation‐‐‐namely, the initial conditions of the associated trajectory. Exploiting the local observability property of the agents we prove that, with a simple sample‐and‐hold or finite summation operation, it is possible to estimate these parameters algebraically. Consensus strategies are then used to fuse the parameter estimates of all agents to reconstruct the complete state vector. Asymptotic or finite convergence time of the observer are established for several scenarios for the graph, including time‐varying, switching and with transmission delays.

Observer design for a class of nonlinear systems combining dissipativity with interconnection and damping assignment

AbstractA nonlinear observer design approach is proposed that exploits and combines port‐Hamiltonian systems and dissipativity theory. First, a passivity‐based observer design using interconnection and damping assignment for time variant state affine systems is presented by applying output injection to the system such that the observer error dynamics takes a port‐Hamiltonian structure. The stability of the observer error system is assured by exploiting its passivity properties. Second, this setup is extended to develop an observer design approach for a class of systems with a time varying state affine forward and a nonlinear feedback contribution. For a class of nonlinear systems, the theory of dissipative observers is adapted and combined with the results for the passivity‐based observer design using interconnection and damping assignment. The convergence of the compound observer design is determined by a linear matrix inequality. The performance of both observer approaches is analyzed in simulation examples.

Adaptive Controller and Observer Design Using Open and Closed-Loop Reference Models for Linear Time-Invariant Systems With Unknown Dynamics

This article presents an output feedback controller and observer design approach for linear time-invariant systems with unknown dynamics. The presented method uses an open-loop reference model to generate the desired trajectory and a closed-loop reference model as an observer. The controller only uses the observer states. Lyapunov-based stability proofs show that the error states converge asymptotically to zero and that all other signals are uniformly stable. Furthermore, bounds are proven on the transient behavior.

On the Observability and Observer Design on the Special Orthogonal Group Based on Partial Inertial Sensing

The aim of this article is to discuss the observability properties and observer design for the attitude of a rigid body, under conditions of partial inertial sensing. In particular, we introduce an observability analysis tool for the attitude dynamics when only accelerometer and gyroscope measurements are available, as in several robotics applications. In various scenarios, in fact, the measurement of the magnetic field via a magnetometer is unreliable, due to magnetic interferences. Herein, we first focus on a formal observability analysis, which reveals that the target dynamics is weakly locally observable , but not first-order observable. The lack of first-order observability prevents standard observers from achieving global convergence. Therefore, we discuss a more suitable approach for observer design to deal with this problem. The proposed approach is validated by providing numerical and experimental results. The former show that the proposed approach is able to achieve convergence (final error 0.004 $\%$ ). Experiments validate our inference about observability and show the improvements brought by the proposed approach concerning the error convergence (final error 0.15 $\%$ ).

ANALYSIS OF NURSE'S JOB SATISFACTION BASED ON INTERNAL SERVICE QUALITY MEASUREMENT

Nurses who are considered by the hospital to be able to provide maximum health services to patients so that they can increase patient satisfaction. This research was conducted to analyze the job satisfaction of nurses based on Internal Service Quality in the inpatient installation of RSI A. Yani Surabaya. The study was conducted with an observational analytic design and cross-sectional approach. The study population was the nurses in the inpatient installation of RSI A. Yani Surabaya, a total of 104 nurses. The sample size was 78 nurses who were spread in each inpatient room of RSI A. Yani Surabaya. The method of sampling using simple random sampling. Data analysis was performed using binary logistic regression test. The results showed that 98.7% of nurses rated internal service quality as good and 64.1% of nurses said they were satisfied. Based on the statistical test, it was found that the value of p = 0.999 ( 0.05), which means that internal service quality has no significant effect on job satisfaction of nurses. However, based on the aspect of internal service quality, the aspects of tools and reward and recognition can provide an almost significant effect on job satisfaction of nurses. Provision of tools has 9.23 times less risk of dissatisfying nurses than providing good tools. Likewise, giving rewards and recognition that was less likely to have a 3.34 times risk of making nurses dissatisfied compared to giving good recognition.

Adaptive Fault Estimation for Unmanned Surface Vessels With a Neural Network Observer Approach

This paper is concerned with the fault reconstruction observer design problem with unknown nonlinearities, external disturbances and faults. First, a neural-network-based fault estimation approach is developed to generate the estimations of the actuator failures. In this design, the neural network strategy is utilized to approximate the totally unknown nonlinear functions. Then, an iterative adaptive observer is designed to offer the accurate estimations of the sensor faults, where the estimations in the previous iteration are applied in the current iteration to guarantee the convergence of sensor fault estimation errors. The developed neural network observer design approach can reconstruct the states, actuator and sensor faults for the unmanned surface vessel simultaneously. Finally, a practical example of the unmanned surface vessel is presented to illustrate the effectiveness and the potential of the proposed observer technique.

Integrated fault tolerant tracking control for rigid spacecraft using fractional order sliding mode technique

In this study, the integrated fault estimation (FE) and fault tolerant control (FTC) design problem is investigated for the attitude system of a rigid spacecraft with inertia uncertainty, Lipschitz nonlinearity, external disturbance and multiple type actuator faults. An adaptive sliding mode observer design approach, which does not require the known upper bound of generalized perturbation, is proposed to obtain the estimation of unknown actuator faults. On this basis, a fault tolerant attitude tracking control scheme is developed for the faulty rigid spacecraft attitude system by combining the fractional order sliding mode control and backstepping control with adaptive fuzzy approximation technique. The stability of faulty closed loop attitude system under the designed FTC strategy is analyzed using Lyapunov approach. Finally, simulation results are given to show the superiority of the proposed integrated FE and FTC compared with some existing results.

Nonfragile H∞ State Estimation for Recurrent Neural Networks With Time-Varying Delays: On Proportional-Integral Observer Design.

In this article, a novel proportional-integral observer (PIO) design approach is proposed for the nonfragile H∞ state estimation problem for a class of discrete-time recurrent neural networks with time-varying delays. The developed PIO is equipped with more design freedom leading to better steady-state accuracy compared with the conventional Luenberger observer. The phenomena of randomly occurring gain variations, which are characterized by the Bernoulli distributed random variables with certain probabilities, are taken into consideration in the implementation of the addressed PIO. Attention is focused on the design of a nonfragile PIO such that the error dynamics of the state estimation is exponentially stable in a mean-square sense, and the prescribed H∞ performance index is also achieved. Sufficient conditions for the existence of the desired PIO are established by virtue of the Lyapunov-Krasovskii functional approach and the matrix inequality technique. Finally, a simulation example is provided to demonstrate the effectiveness of the proposed PIO design scheme.

Observer Design for a Class of Nonlinear Systems With Nonscalar-Input Nonlinear Consequents

This letter presents a discrete-time Takagi-Sugeno fuzzy observer design approach for a class of nonlinear systems. Instead of including all the nonlinear terms in the membership functions, some of them are kept as nonlinear consequents, and they need to fulfill a global Lipschitz condition. The form considered permits nonlinear consequents that depend on nonscalar inputs. The design conditions are defined in terms of linear matrix inequalities, and they are less restrictive than previous conditions from the literature. Two numerical examples highlight the advantages obtained.

Health Disaster Preparedness Using Android Mobile Based Application Case Mount Bromo Eruption

Introduction: In the last 10 years, Mount Bromo has erupted four times; 2004, 2010, 2015 and 2019. However, it is unique that people at Tengger are reluctant to evacuate even though Mount Bromo is erupting and releasing volcanic material such as stones and dust.Methods: This research is a quantitative study, using correlative analytic observational design and cross sectional approach with pourposife sample of 120 taken from online questionare results of bivariate analysis using gamma correlation test obtained the results of knowledge factors (p=0.005; r=0.27) attitude (p=0.000; r=0.45), means of infrastructure (p=0.000; r=0.58), and android application (p=0.000; r=0.59) for health preparedness. Results: Knowledge, attitude, infrastructure and android application factors can influence health preparedness in disaster risk reduction in Bromo area.Using the smartphone application as the Mount Bromo information facilities are one of an effort so that people and tourists can activate if an eruption occurs. There is important health preparedness about features made in the application such as distribution shelters, evacuation routes, health centres, photos, videos, and primary health care information.Conclusion: Assessment results to the application interface, the information conveyed, and the features offered showed that the application was very useful and gives a new perspective in conveying accurate information to the public and also tourists. The health preparedness community level is also quite good with the services provided by the Bromo alert application.

The impact of social capital, demographic factors, and coping strategies on community adaptation in supporting people with severe mental illness.

Background: People with severe mental illness have the ability to live a satisfactory and independent life with the help of the community. Their adaptation to life’s challenges is a dynamic process, and the community plays an important role. This research, therefore, aims to address the question of how social capital, demographic factors, and coping strategies affect the community’s ability to adapt to people with severe mental illness.Design and methods: The multi-stage random sampling was used to obtain data from 137 respondents from rural society using an analytic observational design and cross-sectional approach. In addition, the Somers’ D test was used to measure the effect of social capital, demographic factors, and coping strategies on community adaptation.Results: The results showed a significant effect of social capital, demographic factors, and the coping strategy of community adaptation (P<0.05). Based on empirical research, access to social capital is critical in fostering community adaptation through its social participation, network, trust, coping strategies, and cooperation.Conclusions: In conclusion, social capital, demographic factors, and coping strategies are significant factors in developing community adaptation of people with severe mental illness.Significance for public healthPeople with severe mental illness (PSMI) have difficulties in carrying out daily tasks, therefore, they tend to avoid social interaction. A strong sense of community provides opportunities for PSMI to learn new skills, thereby encouraging an independent life style. The ability of communities to understand the stress experienced by PSMI, enables them to tackle the constraints. This study answers the question associated with the social capital, demographic factors, and coping strategies of communities in coping with mental ill people.

Health Disaster Preparedness Using Android Mobile Based Application Case Mount Bromo Eruption

Introduction: In the last 10 years, Mount Bromo has erupted four times; 2004, 2010, 2015 and 2019. However, it is unique that people at Tengger are reluctant to evacuate even though Mount Bromo is erupting and releasing volcanic material such as stones and dust. Methods: This research is a quantitative study, using correlative analytic observational design and cross sectional approach with pourposife sample of 120 taken from online questionare results of bivariate analysis using gamma correlation test obtained the results of knowledge factors (p=0.005; r=0.27) attitude (p=0.000; r=0.45), means of infrastructure (p=0.000; r=0.58), and android application (p=0.000; r=0.59) for health preparedness. Results: Knowledge, attitude, infrastructure and android application factors can influence health preparedness in disaster risk reduction in Bromo area.Using the smartphone application as the Mount Bromo information facilities are one of an effort so that people and tourists can activate if an eruption occurs. There is important health preparedness about features made in the application such as distribution shelters, evacuation routes, health centres, photos, videos, and primary health care information. Conclusion: Assessment results to the application interface, the information conveyed, and the features offered showed that the application was very useful and gives a new perspective in conveying accurate information to the public and also tourists. The health preparedness community level is also quite good with the services provided by the Bromo alert application.

The correlation between body mass index and menstrual cycle disorders in medical students of Udayana University

Background: One relevant indicator in describing women's reproductive health and quality of life is the menstrual cycle. A high or low body mass index (BMI) can be a risk factor for menstrual disorders including irregular menstrual cycles, absence of menstruation and menstrual pain.&#x0D; Aim: This study aims to determine the correlation between body mass index and menstrual cycle disorders in medical faculty students of Udayana University.&#x0D; Method: This study used observational analytic study design and cross sectional approach. Samples are selected using purposive sampling technique. The samples were students in Medical Faculty of Udayana University with 90 amount of respondents aged 19-22 years old.&#x0D; Result: Based on chi square statistical test, the results obtained with p value= 0,000 (p value &lt;0,05).&#x0D; Conclusion: The conclusion is there is a significant correlation between body mass index and menstrual cycle disorders in medical faculty students of Udayana University.

The Modifying Factor of Lead Exposure Time with Blood Lead Levels on Adulterated Paint Worker

The modifying factor for exposure time for paint workers who work more than 8 hours / day have abnormal blood lead levels&gt; 10 μg / dl. Lead exposure to paint workers occurs when mixing paints, mostly through air, skin, through food and drinks. The longer the work, the more the amount of lead exposure received, although the amount of lead absorbed by the body is only small, this metal turns out to be very dangerous and can cause health problems due to the buildup of lead in the body. The presence of lead (Pb) in the blood can cause severe and dangerous effects including interfering with the hematopoietic system, a long exposure can disrupt the gastrointestinal system, central nervous system, immune system, kidneys. The purpose of this research was to determine the relationship and closeness of the relationship between the modification factors of exposure time with blood lead levels of adulterated paint workers in the area of East Jakarta. The research method uses primary data through an analytic observational cross-sectional design approach. Sampling is done by non-probability sampling with consecutive sampling techniques. The correlation test used was the Spearman test with a confidence level of 95%. The results of the research found that the average exposure time of adulterated paint workers was 48.9 hours/week exceeding the permissible work time, and the exposure time &gt;40 hours/week was 77.5% of the number of respondents. The average blood lead level was 0.15 mg/L, with the highest blood lead level 0.45 mg/L and workers with exposure times&gt; 40 hours/week obtained blood lead levels exceeding the safe reference limit (40 mg/L) of 19.4%. The conclusion is that there is a significant relationship between duration of exposure and lead level of adulterated paint workers (p-value = 0.029) and shows the moderate closeness of the relationship with the direction of a positive relationship. The value of r = 0.346, means that the longer the person is exposed to lead, the higher the level of lead in the blood of adulterated paint workers. The discussion of modification factors of exposure time in adulterated paint workers can influence lead exposure continuously, in the long term, absorption of lead in the body 99% which is bound to erythrocytes will accumulate in the blood, then it is distributed into the blood which is 90% binding to cells red blood cells (erythrocytes), and the rest are bound to blood plasma. Once absorbed, the lead will be stored in the blood for 35 days. For 8 hours, a worker can absorb up to 400 μg and add 20 - 30 μg / day from food, drinks, and air. The presence of lead in blood represents a reflection of the dynamic continuity between exposure, absorption, distribution, and excretion, so that it is one indicator to know and follow ongoing exposure.&#x0D; Keywords : Modifying Effect, Exposure Time, Relationship Strength, Blood Lead Levels