scholarly journals Tightness of Semidefinite Programming Relaxation to Robust Transmit Beamforming with SINR Constraints

2013 ◽  
Vol 2013 ◽  
pp. 1-10 ◽  
Author(s):  
Yanjun Wang ◽  
Ruizhi Shi
Keyword(s):  
Transmit Beamforming ◽  
Semidefinite Programming Relaxation ◽  
Quadratic Constraints ◽  
Worst Case ◽  
Sdp Relaxation ◽  
Relaxation Problem ◽  
System A ◽  
Rank One ◽  
Robust Formulation ◽  
The One

This paper considers a multiuser transmit beamforming problem under uncertain channel state information (CSI) subject to SINR constraints in a downlink multiuser MISO system. A robust transmit beamforming formulation is proposed. This robust formulation is to minimize the transmission power subject to worst-case signal-to-interference-plus-noise ratio (SINR) constraints on the receivers. The challenging problem is that the worst-case SINR constraints correspond to an infinite number of nonconvex quadratic constraints. In this paper, a natural semidifinite programming (SDP) relaxation problem is proposed to solve the robust beamforming problem. The main contribution of this paper is to establish the tightness of the SDP relaxation problem under proper assumption, which means that the SDP relaxation problem definitely yields rank-one solutions under the assumption. Then the SDP relaxation problem provides globally optimum solutions of the primal robust transmit beamforming problem under proper assumption and norm-constrained CSI errors. Simulation results show the correctness of the proposed theoretical results and also provide a counterexample whose solutions are not rank one. The existence of counterexample shows that the guess that the solutions of the SDP relaxation problem must be rank one is wrong, except that some assumptions (such as the one proposed in this paper) hold.

Purification of a Specific Placental Plasminogen Activator Inhibitor by Monoclonal Antibody and Its Complex Formation with Plasminogen Activator

1985 ◽  
Vol 53 (01) ◽  
pp. 122-125 ◽  
Author(s):  
B Åstedt ◽  
Ingegerd Lecander ◽  
T Brodin ◽  
A Lundblad ◽  
Karin Löw
Keyword(s):  
Monoclonal Antibody ◽  
Complex Formation ◽  
Plasminogen Activator ◽  
Plasminogen Activator Inhibitor ◽  
Tissue Type ◽  
System A ◽  
The One ◽  
Fast Acting ◽  
Chain Form ◽  
Activator Inhibitor

SummaryA monoclonal antibody of IgG2a-type was obtained against a specific fast acting plasminogen activator inhibitor found in placenta. The placental inhibitor was purified by affinity chromatography using the monoclonal antibody and additionally in a FPLC-system. A strong complex formation was found between the inhibitor and urokinase and also with the two-chain form of plasminogen activator of the tissue-type. A weaker complex was found between the placental inhibitor and the one- chain form of the tissue-type activator.

scholarly journals Analysis of the robustness of a steel frame structure with composite floors subject to multiple fire scenarios

2021 ◽  
pp. 136943322199249
Author(s):  
Riza Suwondo ◽  
Lee Cunningham ◽  
Martin Gillie ◽  
Colin Bailey
Keyword(s):  
Progressive Collapse ◽  
Three Dimensional ◽  
Steel Structure ◽  
Frame Structure ◽  
Worst Case ◽  
Collapse Resistance ◽  
Fire Scenarios ◽  
Element Approach ◽  
The One ◽  
Steel Frame Structure

This study presents robustness analyses of a three-dimensional multi-storey composite steel structure under the action of multiple fire scenarios. The main objective of the work is to improve current understanding of the collapse resistance of this type of building under different fire situations. A finite element approach was adopted with the model being firstly validated against previous studies available in the literature. The modelling approach was then used to investigate the collapse resistance of the structure for the various fire scenarios examined. Different sizes of fire compartment are considered in this study, starting from one bay, three bays and lastly the whole ground floor as the fire compartment. The investigation allows a fundamental understanding of load redistribution paths and member interactions when local failure occurs. It is concluded that the robustness of the focussed building in a fire is considerably affected by the size of fire compartments as well as fire location. The subject building can resist progressive collapse when the fire occurs only in the one-bay compartment. On the other hand, total collapse occurs when fire is located in the edge three-bay case. This shows that more than one fire scenario needs to be taken into consideration to ensure that a structure of this type can survive from collapse in the worst-case situation.

scholarly journals Parallel One-Step Control of Parametrised Boolean Networks

Mathematics ◽  
2021 ◽  
Vol 9 (5) ◽  
pp. 560 ◽  
Author(s):  
Luboš Brim ◽  
Samuel Pastva ◽  
David Šafránek ◽  
Eva Šmijáková
Keyword(s):  
Control Problem ◽  
Boolean Networks ◽  
Actual State ◽  
Worst Case ◽  
Symbolic Data ◽  
One Step ◽  
The One ◽  
Step Control ◽  
Symbolic Algorithm ◽  
Naive Approach

Boolean network (BN) is a simple model widely used to study complex dynamic behaviour of biological systems. Nonetheless, it might be difficult to gather enough data to precisely capture the behavior of a biological system into a set of Boolean functions. These issues can be dealt with to some extent using parametrised Boolean networks (ParBNs), as this model allows leaving some update functions unspecified. In our work, we attack the control problem for ParBNs with asynchronous semantics. While there is an extensive work on controlling BNs without parameters, the problem of control for ParBNs has not been in fact addressed yet. The goal of control is to ensure the stabilisation of a system in a given state using as few interventions as possible. There are many ways to control BN dynamics. Here, we consider the one-step approach in which the system is instantaneously perturbed out of its actual state. A naïve approach to handle control of ParBNs is using parameter scan and solve the control problem for each parameter valuation separately using known techniques for non-parametrised BNs. This approach is however highly inefficient as the parameter space of ParBNs grows doubly exponentially in the worst case. We propose a novel semi-symbolic algorithm for the one-step control problem of ParBNs, that builds on symbolic data structures to avoid scanning individual parameters. We evaluate the performance of our approach on real biological models.

Clinical Notes on Haemorrhages in General Paralysis

1886 ◽  
Vol 31 (136) ◽  
pp. 504-507
Author(s):  
Geo. H. Savage
Keyword(s):  
Nervous System ◽  
Nervous Disease ◽  
General Paralysis ◽  
Clinical Notes ◽  
System A ◽  
General Pathology ◽  
Mental Symptoms ◽  
The One ◽  
Nutritional Changes

In so-called nervous disorders it is common to find changes occur in other of the bodily systems than the nervous. The pathology of nervous disease should be looked upon as a general pathology, and it is certain that we cannot look to the one system alone for causes of all the nervous disorders without greatly misunderstanding the whole subject. The more exact we become in limiting the causes, the more liable are we to error. We are all prepared to consider general paralysis of the insane as essentially a disease of the nervous system, a disease in which nearly every part of the nervous system may suffer sooner or later. But beside the essentially nervous symptoms which occur in the disease, we are constantly struck by the regular series of nutritional changes which occur in general paralysis, and this is so much the case that we are quite prepared to recognise as general paralysis a disorder in which any mental symptoms have been present, but have after a brief period of acuteness been followed by a state of fatness and weak-mindedness which again has been followed by a period of wasting and further mental weakness. We have here nervous symptoms related very directly with nutritional changes.

Topology Optimization of Dynamic Systems Under Uncertain Loads: An H∞-Norm-Based Approach

2019 ◽  
Vol 14 (2) ◽  
Author(s):  
Paolo Venini
Keyword(s):  
Topology Optimization ◽  
Structural Parameters ◽  
Goal Function ◽  
Dynamic Compliance ◽  
Case Scenario ◽  
Worst Case ◽  
Original Definition ◽  
Optimal Material ◽  
The One ◽  
Definition Of

An innovative approach to topology optimization of dynamic system is introduced that is based on the system transfer-function H∞-norm. As for the structure, the proposed strategy allows to determine the optimal material distribution that ensures the minimization of a suitable goal function, such as (an original definition of) the dynamic compliance. Load uncertainty is accounted for by means of a nonprobabilistic convex-set approach (Ben-Haim and Elishakoff, 1990, Convex Models of Uncertainty in Applied Mechanics, Elsevier Science, Amsterdam). At each iteration, the worst load is determined as the one that maximizes the current dynamic compliance so that the proposed strategy fits the so-called worst case scenario (WCS) approach. The overall approach consists of the repeated solution of the two steps (minimization of the dynamic compliance with respect to structural parameters and maximization of the dynamic compliance with respect to the acting load) until convergence is achieved. Results from representative numerical studies are eventually presented along with extensions to the proposed approach that are currently under development.

Man, Institutions and Bioeconomics

2003 ◽  
Vol 14 (4) ◽  
pp. 339-355
Author(s):  
Javier Alfonso Gil
Keyword(s):  
Methodological Approach ◽  
Natural Habitat ◽  
Social Technology ◽  
Activity System ◽  
Material Technology ◽  
Political Market ◽  
System A ◽  
Biological Capacity ◽  
Growth Of Knowledge ◽  
The One

Because bioeconomics is born of the interaction between the biological activity system and its socio-economic activity system, a holistic methodological approach is essential to study the relations between them. However, it must search for increasing levels of reductionism within each discipline to delve into the ultimate nature of each one of the intervening forces, whether economic or biological. This paper explores the economic forces. Through the biological capacity to comprehend, man and by extension, society, accumulates knowledge, the fulcrum from which he is able to dominate over his natural habitat. From this ‘point d’appui’, man builds two basic tools to assist him in achieving the goal of bettering his social condition. On the one hand, he creates institutions that allow him to “live with others” and, on the other, he develops technology that helps him to “live better with others”. Institutions, also referred to as ‘social technology’, tend toward stability over time while technology or ‘material technology’, tends toward instability, which would suggest that, normally, the mechanics of change will originate in material technology and, from there, progress to social technology by way of the political market. The level of progress and development attained depends on the quantity and rate of growth of knowledge applied by a society. In the process, man and his collectivity are forced to adopt new views of their environment through new shared mental models. The concurrence of equipment and political market will ultimately become the prime mover of institutional and economic change as well as change in mentality. Both technologies must keep on an adaptive course of stable evolution since discrepancies arising between them can cause tension between the various social groups. Adequate management of technological shock is essential to avoid extreme situations of social conflict. Herein lie the most important political decisions that a government must confront over the long term.

scholarly journals Intelligent design af fokusgrupper - om metodisk design af fokusgrupper og menneskets forskellige intelligenser

2008 ◽  
Vol 24 (45) ◽  
pp. 13
Author(s):  
Lene Heiselberg
Keyword(s):  
Focus Groups ◽  
Intelligent Design ◽  
Verbal Intelligence ◽  
Case Scenario ◽  
Worst Case ◽  
Apparent Lack ◽  
Self Confidence ◽  
Media Research ◽  
The One ◽  
Interviewing Techniques

Når man arbejder professionelt med at gennemføre kvalitative mini- og fokusgruppeanalyser, kan det ikke undgås, at man som moderator indimellem tænker: Hvorfor deltager hun ikke? Hvad kan jeg gøre for at inkludere hende i diskussionen? Ofte skyldes nogle deltageres manglende engagement, at mini- eller fokusgruppens metodiske design favoriserer de deltagere, som har en fremtrædende verbalsproglig intelligens, og samtidig ekskluderes de, der har andre fremtrædende intelligenser, fra at yde det maksimale. En sådan situation er meget uheldig og kan i værste fald give en undersøgelse bias. Derfor har vi i DR Medieforskning arbejdet med en pragmatisk tilgang til problemet, hvor vi har afprøvet et metodisk design, som inkluderer kvalitative interviewteknikker og procesværktøjer, som appellerer til samtlige intelligenser. Som et resultat af en målrettet indsats for at inkludere flere intelligenser i det metodiske design, oplever vi, at deltagerne har mere lyst til at engagere sig og gør det med større selvsikkerhed. Desuden oplever vi i mindre grad fænomenet “cognitive tuning” , og derfor kan vi arbejde med flere og bedre data i analyse- og fortolkningsfasen. Intelligent design of focus groups - article about methodological design of focus groups and the different intelligences When you work professionally with the conducting and moderating of qualitative mini- and focus groups, you can't avoid sometimes thinking: Why isn’t she participating? What can I do to include her in the discussion? A participant's apparent lack of enthusiasm is often caused by the methodological design of the focus group giving preference to participants who have an explicit verbal intelligence, and as a consequence excludes participants with other explicit intelligences from contributing. A situation like the one described above is very undesirable and in a worst-case scenario it can cause a study to be biased. In order to try to solve this problem DR Media Research applied a methodological design which includes qualitative interviewing techniques and processing tools, which appeal to all of the intelligences instead of just one. As a result of this work, we find that the participants are more eager to participate and that they do it with greater self-confidence. In addition we encounter less cognitive tuning, and are therefore able to work with richer data in the phases of analysis and interpretation.

scholarly journals Gut microbiota and renin-angiotensin system: a complex interplay at local and systemic levels

2021 ◽  
Author(s):  
Kinga Jaworska ◽  
Mateusz Koper ◽  
Marcin Ufnal
Keyword(s):  
Gut Microbiota ◽  
Renin Angiotensin System ◽  
Gastrointestinal Diseases ◽  
Electrolyte Balance ◽  
Ample Evidence ◽  
Angiotensin System ◽  
Renin Angiotensin ◽  
System A ◽  
Potential Mediator ◽  
The One

Gut microbiota is a potent biological modulator of many physiological and pathological states. The renin-angiotensin system (RAS), including the local gastrointestinal RAS (GI RAS), emerges as a potential mediator of microbiota-related effects. The RAS is involved in cardiovascular system homeostasis, water-electrolyte balance, intestinal absorption, glycemic control, inflammation, carcinogenesis and aging-related processes. Ample evidence suggests a bidirectional interaction between the microbiome and RAS. On the one hand, gut bacteria and their metabolites may modulate GI and systemic RAS. On the other hand, changes in the intestinal habitat caused by alterations in RAS may shape microbiota metabolic activity and composition. Notably, the pharmacodynamic effects of the RAS-targeted therapies may be in part mediated by the intestinal RAS and changes in the microbiome. This review summarizes studies on gut microbiota and RAS physiology. Expanding the research on this topic may lay a foundation for new therapeutic paradigms in gastrointestinal diseases and multiple systemic disorders.

scholarly journals An Analytic Theologian Stance on the Existence of God

2013 ◽  
Vol 5 (2) ◽  
pp. 129-146 ◽  
Author(s):  
Benedikt Paul Göcke
Keyword(s):  
Point Of View ◽  
The Other ◽  
Philosophical Discussion ◽  
Existence Of God ◽  
Worst Case ◽  
The One

The existence of God is once again the focus of vivid philosophical discussion. From the point of view of analytic theology, however, people often talk past each other when they debate about the putative existence or non- existence of God. In the worst case, for instance, atheists deny the existence of a God, which no theists ever claimed to exist. In order to avoid confusions like this we need to be clear about the function of the term ‘God’ in its different contexts of use. In what follows, I distinguish between the functions of ‘God’ in philosophical contexts on the one hand and in theological contexts on the other in order to provide a schema, which helps to avoid confusion in the debate on the existence or non-existence of God.

scholarly journals Robust Secure Beamforming Design for Cooperative Cognitive Radio Nonorthogonal Multiple Access Networks

2021 ◽  
Vol 2021 ◽  
pp. 1-9
Author(s):  
Quanzhong Li ◽  
Sai Zhao
Keyword(s):  
Cognitive Radio ◽  
Secure Communication ◽  
Multiple Access ◽  
Spectrum Efficiency ◽  
Maximization Problem ◽  
Artificial Noise ◽  
Practical Case ◽  
Secrecy Rate ◽  
Worst Case ◽  
Rank One

By the integration of cooperative cognitive radio (CR) and nonorthogonal multiple access (NOMA), cooperative CR NOMA networks can improve the spectrum efficiency of wireless networks significantly. Due to the openness and exposure of wireless signals, secure communication is an important issue for cooperative CR NOMA networks. In this paper, we investigate the physical layer security design for cooperative CR NOMA networks. Our objective is to achieve maximum secrecy rate of the secondary user by designing optimal beamformers and artificial noise covariance matrix at the multiantenna secondary transmitter under the quality-of-service at the primary user and the transmit power constraint at the secondary transmitter. We consider the practical case that the channel state information (CSI) of the eavesdropper is imperfect, and we model the imperfect CSI by the worst-case model. We show that the robust secrecy rate maximization problem can be transformed to a series of semidefinite programmings based on S-procedure and rank-one relaxation. We also propose an effective method to recover the optimal rank-one solution. Simulations are provided to show the effectiveness of our proposed robust secure algorithm with comparison to the nonrobust secure design and traditional orthogonal multiple access schemes.

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