Separation Principle Research Articles

M. M. Speransky – a person, a citizen, a statesman

The history periodically introduces us to really brilliant people, who are, as a rule, not appreciated by contemporaries. M.M. Speransky can rightfully be considered such a genius. A brilliant student of the seminary, a responsible official, an executive forwarder and head of the office, became a victim of court intrigues. However, even after his exile and return, Speransky turned out to be useful to the court of Emperor Nicholas I.The purpose of the research is to analyze the life and views of an outstanding politician of the first quarter of the 19th century, whose transformations were not appreciated in a timely manner, butwhose benefits are obvious at the present time. In the study the following methods have been used: the retrospective one allowing you to immerse yourself in the events of the past, the historical andgenetic method, revealing the specifics of M.M. Speransky’s views, and the chronological one. The results of the research consist in the study and analysis of M.M. Speransky ‘s life and political views as an ideological inspirer of state reforms. The conclusions made are: M. Speransky’s ideas were embodied in the future in the such well-known political institutions as the State Council, the bicameral parliament, the principle of separation of powers.

Primary immunodeficiencies (PID) Life Index in Southeast Asia: A comparative analysis of PID Principles of Care (PoC).

To analyze the implementation of the Principles of Care (PoC) in primary immunodeficiencies (PID) in Southeast Asia (SEA) countries - six years after its call of action. Using the newly developed PID Life Index software, the index of implementation of principles of care in the management of PIDs patients involving the six participating SEA countries (Cambodia, Indonesia, Malaysia, Vietnam, Thailand, and Philippines) were extracted. For each of the six separate principles, the index from the six countries will be compared and presented based on the calculated index. Comparative analysis of the six principles of care of PID in the SEA countries showed low diagnostic rate with minimal availability of diagnostic tests options. Generally, almost all SEA countries provide curative treatments, vaccines, and anti-infectious therapies although the reimbursement scheme varied in relieving patients' financial burden. We also highlighted the active involvement of patient organizations in SEA, with main areas of work focused on advocacy and increasing awareness among public and healthcare professionals. It is applaudable that the SEA continent is gradually strengthening its work in management of PID, especially in Thailand and Vietnam. However, more emphasis must be placed among stakeholders in SEA countries towards successful implementation of the PoC for a holistic management of PID patients.

An Investigation of India's and Pakistan's Legal Systems through the Lens of Rule of Law

The rule of law furthers the goals of nationhood and peace throughout developmental processes. It's the bedrock of a free society, and democratic values are nothing more than a buzzword if the courts aren't entirely independent and the legislature and president don't treat them with the respect they deserve. Respect and autonomy thrive when one state institution may rein in the authority of another state institution (a phenomenon known as "horizontal accountability"). The principle of separation of powers among governmental authorities is essential to the rule of law. This paper will compare the rule of law in India and Pakistan, with a particular emphasis on the role of the judiciary in each country's legal system. It will also investigate the facts surrounding the question of whether or not governmental powers are constrained when it comes to protecting citizens' basic liberties. At the same time, the effects of a purely hypothetical version of the rule of law on its observance will be examined. The study will also compare and contrast the two nations' levels of representative government and the ease with which citizens may obtain civil justice.

Integrating Fly Ash-Controlled Surface Morphology and Candle Grease Coating: Access to Highly Hydrophobic Poly (L-lactic Acid) Composite for Anti-Icing Application

New ways of recycling fly ash are of great significance for reducing the environmental pollution. In this work, biodegradable hydrophobic poly (L-lactic acid)/fly ash composites for anti-icing application were successfully fabricated via a facile solvent-volatilization-induced phase separation approach. A silane coupling agent of 3-(Trimethoxysilyl) propyl methacrylate was used to decorate a fly ash surface (FA@KH570) for strengthening the interface bonding between fly ash and poly (L-lactic acid). Moreover, FA@KH570 could obviously enhance the crystallinity of poly (L-lactic acid) (PLLA)/FA@KH570 composites, which accelerated the conversion from the liquid-liquid to the liquid-solid phase separation principle. Correspondingly, the controllable surface morphology from smooth to petal-like microspheres was attained simply by adjusting the FA@KH570 content. After coating nontoxic candle grease, the apparent contact angle of 5 wt% PLLA/FA@KH570 composite was significantly increased to an astonishing 151.2°, which endowed the composite with excellent anti-icing property. This strategy paves the way for recycling waste fly ash and manufacturing hydrophobic poly (L-lactic acid) composite for potential application as an anti-icing material for refrigerator interior walls.

Diagnosis of Viral Infections: A Review of the Current Assays and the Prediction of the Future

Different types of diagnostics methods were introduced to the public due to the recent global pandemic. From the real-time Reverse Transcript Polymerase Chain Reaction (RT-qPCR) to antigen Lateral Flow Assay (LFA), these tests allow relatively accurate and rapid diagnosis of the infection with SARS-CoV-2 virus. Because each assay has separate principles, benefits, and limitations, the diagnostic methods in the future, especially with the rapid development of new techniques, could provide quick, accurate, and accessible Point-Of-Care Testing (POCT). New technologies could be used to identify the virus for future epidemics or other infections that occur in every-day lives, potentially stopping another global pandemic from affecting the community, the economy, and the government.

Развитие судопроизводства в Крыму (период Крымского ханства)

The article reviews historical and social conditions that have affected the establishment of the system of judicial proceedings in the Crimean Khanate. The author studies the importance of various (religious, political and cultural) prerequisites that have affected the development and functioning of the legal system in Crimea from the 15th to the 17th century. Besides, the author reviews separate principles and aspects of development of the judicial procedure in the Crimean Khanate.

Parametric design method for partial eigenstructure assignment of second-order linear systems via observer-based state feedback

In this article, a parametric method of observer-based partial eigenstrunt in second-order linear time-invariant (LTI) systems is explored. First, an observer is constructed to approximate the full sate vector when the entire state vector is not available for measurement. Meanwhile, the separation principle of the first-order linear systems is extended to second-order linear systems. Second, by partitioning the system matrix of the open-loop system into two parts, the satisfactory and unsatisfactory eigenstructures are selected. On the premise of retaining the satisfactory part in the open-loop system, the unsatisfactory eigenstructure assignment problem can be converted into the solutions of a type of generalized Sylvester equations (GSE). Third, by introducing a group of arbitrary parameters, complete parametric expressions of the proportional plus derivative (PD) state feedback controller can be obtained. The main advantage of the proposed method is that it provides all the design degrees of freedom and reduces the design complexity of the controller. Finally, the correctness of the proposed method is verified by two examples and simulation results. Using the degrees of freedom of the parameters, the gain matrices are optimized through the optimization index provided by the optimization function, and better performance is obtained.

Observer-Based Controller Using Line Integral Lyapunov Fuzzy Function for TS Fuzzy Systems: Application to Induction Motors

This paper deals with the stabilization problem of a nonlinear system described by a Takagi–Sugeno fuzzy (TSF) model with unmeasurable premise variables via a robust controller. Applying the sector nonlinearity techniques, the nonlinear system is represented by a decoupled fuzzy model. Then, we design a robust observer-based controller for the obtained fuzzy system by utilizing the differential mean value approach. The observer and controller gains are obtained by the separation principle, in which the problem is solved in the sum of linear matrix inequalities (LMIs). The paper presents two main contributions: A state feedback controller is designed using differential mean value (DMVT) which ensures robust stabilization of the nonlinear system. Additionally, the Luenberger observer is extended to the Takagi–Sugeno fuzzy models. The second contribution is to reduce conservatism in the obtained conditions, a non-quadratic Lyapunov function (known as the line integral Lyapunov fuzzy candidate (LILF)) is employed. Two examples are provided to further illustrate the efficiency and robustness of the proposed approach; specifically, the Takagi–Sugeno fuzzy descriptor of an induction motor is derived and a robust observer-based controller applied to the original nonlinear system.

Distributed control for a class of nonlinear systems based on distributed high-gain observer

This paper concerns the problem of designing distributed control law for a class nonlinear system in which the measurement outputs of the system are distributed in different subsystems. It leads to a challenge that the states of the original systems cannot be completely reconstructed by any single subsystem. In order to solve this problem, distributed state observers and the distributed observer-based distributed control problem emerges as the times require. However, the distributed observers problem of the nonlinear systems is rarely studied, and the distributed control law formed by distributed nonlinear observers has hardly ever been studied up to now. To this end, this paper develops the distributed high-gain observers for a class of nonlinear systems. Unlike the previous several results, our study has the ability to deal with model uncertainty, and devotes itself to overcoming the problem that the separation principle is not tenable. In addition, based on the state estimate generated by the designed distributed observer, an output feedback control law formed by applying the state estimate is developed. Furthermore, a class of sufficient conditions is proved for guaranteeing the error dynamics of the distributed observer and the state trajectory of the closed-loop system to enter an arbitrary small invariant set around the origin. Finally, the simulation results verify the effectiveness of the proposed method.

Effect of right-angled ribbed geometry on the performance of a Ranque–Hilsch vortex tube: A numerical study

The working principle for the energy separation observed in a Ranque–Hilsch Vortex Tube (RHVT) is a matter that is widely debated and unsettled. It is, however, indisputable that modifications to the tube geometry can substantially affect the performance of the tube. In this paper, a three-dimensional computational fluid dynamic study is performed to investigate the enhanced performance of a geometrically modified vortex tube by studying the flow structure, heat transfer, and energy separation. The novel vortex tube is modeled in ANSYS FLUENT, similar to the original device: 3D Steady-state flow analysis using the standard k-ϵ turbulence model on a hybrid mesh. The results acquired are compared and found to demonstrate the increase in the observed energy separation in the novel geometry. The total increase in thermal separation for the novel design is observed to be 15.1 K at 0.9 Cold Mass Fraction, with an increase of 10 W in overall energy transfer. Compared to the nominal design, a maximum of 13.74 percent improvement in thermal separation. Furthermore, the flow structures are compared to understand the reason behind the increased performance. It is found that the factors responsible for the extent of separation of energy in the tube are: Higher Radial Pressure Gradient, Higher Circumferential, and Axial Shear Work, and Conductive Heat Transfer. Finally, an energy balance is carried out on the peripheral hot control volume to study the fundamental modes of energy transfer. The energy balance verifies that these factors are the prominent factors responsible for the observed increase in separation.

Cellular liquid-liquid phase separation: Concept, functions, regulations, and detections.

Liquid-liquid phase separation is a multicomponent system separated into phases with different compositions and structures. It has been identified and explored in organisms after being introduced from the thermodynamic field. Condensate, the product of phase separation, exists in different scales of cellular structures, such as nucleolus, stress granules, and other organelles in nuclei or cytoplasm. And also play critical roles in different cellular behaviors. Here, we review the concept, thermodynamical and biochemical principles of phase separation. We summarized the main functions including the adjustment of biochemical reaction rates, the regulation of macromolecule folding state, subcellular structural support, the mediation of subcellular location, and intimately linked to different kinds of diseases, such as cancer and neurodegeneration. Advanced detection methods to investigate phase separation are collected and analyzed. We conclude with the discussion of anxiety of phase separation, and thought about how progress can be made to develop precise detection methods and disclose the potential application of condensates.

Technologies and Applications of Pipeline-type Oil-gas-water Separation

The separation of oil, gas, and water mixture is an important process in the production of crude oil. Traditional separation tanks are large, heavy, long in separation time, and high cost to manufacture. This paper introduces a separation technology with the main characteristics of the pipeline structure. This technology uses the principles of centrifugation, expansion, air flotation, and gravity separation. Pipes and other equipment are the core equipment, which has the advantages of flexible process composition, small footprint, and high separation efficiency. This technology can be used for rapid oil, gas, and water separation, solving the problems of expansion, upgrading old oilfield stations, realizing the purpose of re-injection of water in-situ, energy saving, and reducing emissions.

The principle of separation of powers in the United States of America and its impact on public liberties

The framers of the US Federal Constitution of 1787 wanted to adopt the principle of ensuring a balance between each of the three authorities (executive-legislative-judicial) on the one hand, and achieving coordination between the powers and authorities of the federal government and the state government on the other hand. In order to achieve public freedoms within society. The Founding Fathers also wanted to guarantee the rights and freedoms of the American people. Those rights that were taken away during the subjection of the American colonies to the British crown and during the reduction of the volume of these freedoms during the successive American administrations under the pretext of preserving national security and others. For this reason, the study was the subject of research Within two axes: the first dealt with the stages of formation of the US Constitution and its basic amendments. The second took it upon himself to discuss public freedoms under the authorities of the United States of America and separate them. To cover some concepts of justice, privacy, individuality, public freedoms and democracy in contemporary American history according to the political, social and security data that affected the functioning of this totalitarian system within society in America

Features of L-Menthol Crystallization in Optically Active Medium Based on L- and D-Asparaginate Chitosan

The phase separation kinetics of an ethanolic L-menthol solution in an aqueous solution of optically and biologically active chitosan L- and D-aspartate was studied. It has been established that this process proceeds according to the extraction crystallization mechanism and combines two types of phase separation, namely: liquid–liquid and liquid–crystal. The effect of aspartic acid stereoisomer, chitosan molecular weight, and polymer: acid ratio on the optical, structural-morphological, and dimensional characteristics of dispersed phase droplets at the initial stage of phase separation and crystal aggregates of the L-menthol condensed phase at the final stage was assessed. In the chitosan D-aspartate medium, as well as with an increase in the concentration of components in the optically active medium and the molecular weight of the polymer, the rate of phase separation, the size of droplets and particles increase. It has been suggested that the system under study is promising for encapsulating hydrophobic drugs, creating chirooptic waveguides, and sensors for biomedical purposes, as well as developing new methods for studying the fundamental principles of phase separation in intracellular regulation of membraneless organelles and subcellular organization of biosystems, including under stress conditions of a living organism underlying the development of new pharmaceuticals to treat rare and currently incurable diseases.

Fast finite-time observer-based sliding mode controller design for a class of uncertain nonlinear systems with input saturation

In this paper, a novel fast finite-time velocity observer-based terminal sliding mode controller is proposed for a class of multi-input multi-output nonlinear systems in the presence of unknown time-varying matched uncertainties and input saturation constraint. The considered nonlinear system is a chain of interdependent second-order nonlinear subsystems that can describe a multitude of real practical applications. The notion of an auxiliary system is introduced and utilized to deal with the input saturation. Due to the hardship of measuring and accessibility to all the system states, a robust output feedback sliding mode controller is designed based on nonsingular fast terminal sliding surfaces exploiting the estimated states and the auxiliary system’s states which is capable of alleviating the control signal gains and enhancing the convergence rate. By noticing that the separation principle does not hold in nonlinear systems, analyzing the finite-time stability of the closed-loop system is a challenging problem and will be assured via an innovative Lyapunov function candidate. Moreover, an explicit adjustable finite convergence time is derived. Simulation results on two practical systems consisting of a two-degree-of-freedom rigid robotic manipulator and Van der Pol oscillator illustrate the effectiveness and superiority of the suggested control scheme.

Phase separation in fungi.

Phase separation, in which macromolecules partition into a concentrated phase that is immiscible with a dilute phase, is involved with fundamental cellular processes across the tree of life. We review the principles of phase separation and highlight how it impacts diverse processes in the fungal kingdom. These include the regulation of autophagy, cell signalling pathways, transcriptional circuits and the establishment of asymmetry in fungal cells. We describe examples of stable, phase-separated assemblies including membraneless organelles such as the nucleolus as well as transient condensates that also arise through phase separation and enable cells to rapidly and reversibly respond to important environmental cues. We showcase how research into phase separation in model yeasts, such as Saccharomyces cerevisiae and Schizosaccharomyces pombe, in conjunction with that in plant and human fungal pathogens, such as Ashbya gossypii and Candida albicans, is continuing to enrich our understanding of fundamental molecular processes.

Design of PDMS/SiO2@MXene composites with “Floatable Interlayer” structure for the electromagnetic shielding behavior improvement

Designing inhomogeneous structure is an efficient method to prepare polymer composites with electromagnetic interference (EMI) shielding. According to principle of phase separation induced by volatilizing solvent, herein, sandwich structure with a SiO2@MXene “floatable interlayer” is designed by regulating the affinity of mixed solvents (dimethylbenzene and tetrahydrofuran) and SiO2@MXene, and then compounded with poly(dimethylsiloxane) (PDMS). The interactions among SiO2@MXene, PDMS and mixed solvents can be dynamically adjusted during solvents evaporation via controlling the nano-SiO2 in/on MXene, which accurately regulates the dispersion of SiO2@MXene in PDMS for further forming floatable conductive interlayer. The composite PDMS/SiO2@MXene-0.25 (SiO2: MXene = 0.25) containing 10 wt% of MXene exhibits typical sandwich structure owing to the opportune specific surface area (545.42 m2 g−1) and surface-loaded SiO2 of the SiO2@MXene-0.25 nanohybrids. The special sandwich structure brings superior performances to the PDMS/SiO2@MXene composites including an average EMI shielding effectiveness of 43.3 dB (0.2 mm in thickness) in X-band, stable mechanical property (remain > 97% after 150 cycles of stretch testing) and wide temperature window in application (-50 ∼ 200 °C). Thus, this study provides a novel method for designing sandwich-like heterostructure of PDMS/SiO2@MXene composites that can be used for EMI shielding in a wide temperature range.

Label-Free Separation of Circulating Tumor Cells and Clusters by Alternating Frequency Acoustic Field in a Microfluidic Chip

Circulating tumor cells (CTCs) play an important role in the prognosis and efficacy evaluation of metastatic tumors. Since CTCs are present in very low concentrations in the blood and the phenotype is dynamically changing, it is a great challenge to achieve efficient separation while maintaining their viability. In this work, we designed an acoustofluidic microdevice for CTCs separation based on the differences in cell physical properties of size and compressibility. Efficient separation can be achieved with only one piece of piezoceramic working on alternating frequency mode. The separation principle was simulated by numerical calculation. Cancer cells from different tumor types were separated from peripheral blood mononuclear cells (PBMCs), with capture efficiency higher than 94% and a contamination rate of about 1% was obtained. Furthermore, this method was validated to have no negative effect on the viability of the separated cells. Finally, blood samples from patients with different cancer types and stages were tested, with measured concentrations of 36-166 CTCs per milliliter. Effective separation was achieved even when the size of CTCs is similar to that of PBMCs, which has the prospect of clinical application in cancer diagnosis and efficacy evaluation.

Optimization of the Course Movement of an Unmanned Vehicle in the Presence of Obstacles and Disturbances

The article discusses the optimization of the control process of an unmanned vehicle. Currently, there is an active development and use of unmanned vehicles. There is a practice of using unmanned shuttles in closed areas (conferences, forums, etc.). The use of cars with automated control in urban conditions and on rough terrain is being tested. In this regard, it is important to develop control algorithms that allow solving problems of car control in real time under the influence of disturbances and the presence of obstacles. With the development of technology and an increase in computing power, it becomes possible to use optimal control algorithms that allow you to achieve better results when the terminal conditions are met, minimizing energy costs. This paper shows the solution of the problem of optimal control of an unmanned vehicle in the presence of a penalty function, measurement noise and disturbances from incomplete data using the separation principle. The problem of optimal control in a deterministic and stochastic setting is solved using an algorithm with a predictive model with a generalized work functional. The effectiveness of applying the Kalman filter is shown depending on the different intensity of measurement noise and different vehicle speeds. The results of numerical modeling are presented, showing the possibility of using the proposed algorithm to control an unmanned vehicle under various initial and final conditions. The developed algorithm has been successfully applied to bypass a moving object.

Observer-based event-triggered leader-following consensus of multi-agents with generalized Lipschitz nonlinear dynamics

This paper discusses a leader-following consensus problem for nonlinear multi-agent systems (MASs) subjected to generalized Lipschitz-type nonlinearity using output feedback. An event-triggered (ET) leader-following control scheme, based upon estimated states using observers, is proposed for efficient bandwidth utilization by application of invariant sets. Distributed observers are designed to estimate the states of the followers because actual states are not always readily available. Besides, in order to reduce unnecessary data communication among the followers, an ET strategy has been formulated which excludes Zeno behavior as well. Under this proposed scheme, sufficient conditions are formulated using Lyapunov theory. These conditions not only guarantee the asymptotic stability of estimation error, but also ensure the tracking consensus of nonlinear MASs. Further, a simple and less conservative design approach using a decoupling scheme for assuring necessity and sufficiency for the main design approach has also been explored. The decoupling scheme is similar to separation principle for linear systems. Contrary to the existing works, the nonlinear systems considered in this study cover a wide family of Lipschitz nonlinearities, including both globally and locally Lipschitz systems. Moreover, the proposed approach is more efficient in handling ET consensus. Finally, the obtained results are verified with single link robots and modified Chua’s circuits.