Physical State Conditions Research Articles

Tensionless tales of compactification

We study circle compactifications of tensionless bosonic string theory, both at the classical and the quantum level. The physical state condition for different representations of BMS3, the worldsheet residual gauge symmetry for tensionless strings, admits three inequivalent quantum vacua. We obtain the compactified mass spectrum in each of these vacua using canonical quantization and explicate their properties.

Effect of loss of bond on the behaviour of RC beams under service load conditions

Deviation of the flexural reinforcement spacing from code specifications appears to underly the cause of the loss of bond (LoB) between concrete and steel that preceded the unexpected collapse of the top-floor balcony of a building under service load conditions on 15 October 2021 in Athens. Although rare, LoB has also been identified as the cause of collapse of buildings under similar conditions in the UK and Canada. However, the codes of practice for reinforced concrete (RC) design neither make reference to the effect of LoB on structural behaviour, nor include LoB in the parameters that the formulae currently used for assessing load-carrying capacity are dependent on. In view of this, a description of the effect of LoB on the function of RC beams is provided in this paper and this description is used as the basis for the derivation of a formula linking LoB with load-carrying capacity. The validity of the proposed formula is verified using published experimental information on the subject. The proposed formula is used for the structural assessment of the collapsed balcony, taking into account the design details, physical state and loading conditions of structural members similar to the one that collapsed.

Readiness for discharge from hospital: a concept analysis

PurposeThis study aimed to analyze and define the concept of readiness for hospital discharge (RHD) in patients with myocardial infarction (MI).Design/methodology/approachWalker and Avant's approach was used for concept analysis. Electronic text searches were performed using valid databases with “readiness for hospital discharge” and “MI” keywords. The research included quantitative and qualitative studies related to RHD published between 1997 and 2021 in English and Persian. Out of 103 obtained articles, 29 met the inclusion criteria.FindingsIn the analysis, the authors identified stable physical state, desirable individual and social conditions, psychological stability, adequate support, adequate information and knowledge, and multidisciplinary care as the attributes of the determinants of RHD. Antecedents were divided into two categories, including preadmission conditions (economic and social, etc.) and postadmission conditions (disease severity and patient health needs, etc). The consequences were also identified as both positive (e.g. self-care) and side effects (e.g. reduced readmission).Originality/valueThe results showed that the concept of RHD in MI patients is a complex and multidimensional condition that applies to all patients on discharge. It is critical for the care team to pay attention to its attributes and scopes in the process of preparing the patient for discharge. It is also suggested that the concept be used as a nursing diagnosis on the North American Nursing Diagnosis Association (NANDA) list. The Association provides nurses with an up-to-date list of nursing diagnoses.

State of Charge Dual Estimation of a Li-ion Battery Based on Variable Forgetting Factor Recursive Least Square and Multi-Innovation Unscented Kalman Filter Algorithm

Battery management is the key technical link for electric vehicles. A good battery management system can realize the balanced charge and discharge of batteries, reducing the capacity degradation and the loss of health caused by battery overcharge and discharge, which all depend on the real-time and accurate estimation of the battery’s state of charge (SOC). However, the battery’s SOC has highly complex nonlinear time-varying characteristics related to the complex chemical and physical state and dynamic environmental conditions, which are difficult to measure directly, and this has become a difficulty in design and research. According to the characteristics of ternary lithium-ion batteries of electric vehicles, a battery SOC dual estimation algorithm based on the Variable Forgetting Factor Recursive Least Square (VFFRLS) and Multi-Innovation Unscented Kalman Filter (MIUKF) is proposed in this paper. The VFFRLS algorithm is used to estimate battery model parameters, and the MIUKF algorithm is used to estimate the battery’s SOC in real time. The two algorithms are coupled to update battery model parameters and estimate the SOC. The experiment results show that the algorithm has high accuracy and stability.

Deriving on-shell open string field amplitudes without using Feynman rules

Abstract We present a series of new gauge-invariant quantities in Witten’s open string field theory. They are defined for a given set of open string states which satisfy the physical state condition around a classical solution. For known classical solutions, we demonstrate that these gauge-invariant quantities compute on-shell tree-level scattering amplitudes around the corresponding D-brane configuration.

Quantization of Gravity and Finite Temperature Effects

Gravity is perturbatively renormalizable for the physical states which can be conveniently defined via foliation-based quantization. In recent sequels, one-loop analysis was explicitly carried out for Einstein-scalar and Einstein-Maxwell systems. Various germane issues and all-loop renormalizability have been addressed. In the present work we make further progress by carrying out several additional tasks. Firstly, we present an alternative 4D-covariant derivation of the physical state condition by examining gauge choice-independence of a scattering amplitude. To this end, a careful dichotomy between the ordinary, and large gauge symmetries is required and appropriate gauge-fixing of the ordinary symmetry must be performed. Secondly, vacuum energy is analyzed in a finite-temperature setup. A variant optimal perturbation theory is implemented to two-loop. The renormalized mass determined by the optimal perturbation theory turns out to be on the order of the temperature, allowing one to avoid the cosmological constant problem. The third task that we take up is examination of the possibility of asymptotic freedom in finite-temperature quantum electrodynamics. In spite of the debates in the literature, the idea remains reasonable.

Experimental study on internal erosion and seepage in the foundation of a dike under variable water head

Internal erosion is one of the main causes of dike failures. Their failure mechanism is related to the physical characteristics (distribution of particle size, permeability characteristics, clay content, etc.), stress state, and hydraulic conditions of the soil around the dikes. In this study, a series of erosion tests under different rising rates of the water head were conducted to study the internal erosion mechanism of a dike foundation under varying hydraulic conditions. It was found that different water head rising rates resulted in different internal erosion failure modes; furthermore, two critical values of water head rising rate were observed that decided whether erosion or piping occurred, and influenced the failure destructiveness of the internal erosion. Under the action of a continuous water head, the continuous failure through internal erosion occurred primarily in four stages. Moreover, under different water head rising rates, the change rules of the water head, seepage flow, and Jx–Q (average horizontal hydraulic gradient–seepage flow) curve were different. The mechanism of internal erosion and the critical hydraulic gradient could be determined based on the Jx–Q change characteristics. The backward erosion piping, based on the well flow model, suggested that the water head changing rate influenced the piping process.

Quantization viewed as Galois extension

Quantization is studied from a viewpoint of field extension. If the dynamical fields and their action have a periodicity, the space of wave functions should be algebraically extended `a la Galois, so that it may be consistent with the periodicity. This was pointed out by Y. Nambu three decades ago. Having chosen quantum mechanics (one dimensional field theory), this paper shows that a different Galois extension gives a different quantization scheme. A new scheme of quantization appears when the invariance under Galois group is imposed as a physical state condition. Then, the normalization condition appears as a sum over the product of more than three wave functions, each of which is given for a different root adjoined by the field extension.

Attenuation of Palm Stearin Emulsion Droplet in Vitro Lipolysis with Crystallinity and Gastric Aggregation.

Emulsions with partially crystalline solid (SE) and undercooled-liquid (LE) droplets with equivalent droplet sizes (centering ∼416 nm), surface charges (∼-56 mV), and spherical morphologies were prepared by hot microfluidization based on 10% palm stearin and 0.4% Span 60. Lipid crystallinity attenuated earlygastroduodenal lipolysis in vitro ( p < 0.05), both with and without inclusion of a gastric phase ( p < 0.05). Gastric exposure, in particular acidic pH, led to partial coalescence of SE and flocculation and partial crystallization of LE, and it attenuated the rate and extent of lipolysis in both samples. In vitro shear conditions further impacted colloidal stability, particularly for SE, with implications for digestibility. Although lipid crystallinity consistently attenuated early lipolysis, gastric-phase SE partial coalescence had a relatively greater impact on digestibility than did droplet physical state. These findings show that a complex interplay exists among a droplet's physical state, colloidal properties, and digestion conditions, which combine to impact emulsion in vitro lipolysis.

A note on circle compactification of tensile ambitwistor string

We discuss a number of problems associated with the circle compactification of the bosonic tensile ambitwistor string with the asymmetric vacuum choice. By considering the spectrum and physical state conditions, we show that the circle radius plays a role as a tuning parameter which determines the low energy effective field theory. At the self dual point, we construct the current operators and compute OPEs between them. While the final outcome remains as yet inconclusive, several new results are obtained. Through the current algebra analysis we show that there is a subsector of the massless states where the gauge symmetry is enhanced to ISO(2)L×SU(2)R. Using the fact that the one loop partition function is not modular invariant, we show that tensile ambitwistor string partition function is exactly the same as a field theory partition function. Our result proves that despite the existence of winding modes, which is a typical characteristic of a string, the tensile ambitwistor string behaves as a point particle theory.

Mathematical foundation of foliation-based quantization

We have recently proposed in \cite{Park:2014tia} the quantization of pure 4D Einstein gravity through hypersurface foliation, and observed that the 4D Einstein gravity becomes renormalizable once all (or most) of the unphysical degrees of freedom are removed. In this work, we confirm this observation from a more mathematical angle. In particular, we show that the physical state condition arising from the shift vector constraint connects with the requirement that the manifold admit "totally geodesic (TG) foliation". The TG foliation, in turn, makes it possible to view the 4D manifold as abelian fibration over a 3D base. Associating the abelian fibration with the 4D diffeomorphism leads to reduction of the 4D manifold to 3D, thereby realizing and generalizing the holography of 't Hooft.

The Choice of Renal Replacement Therapy (CORETH) project: dialysis patients' psychosocial characteristics and treatment satisfaction.

Until today, research has underestimated the role of psychosocial conditions as contributing factors to dialysis modality choice. The novelty within the Choice of Renal Replacement Therapy (CORETH) project (German Clinical Trials Register #DRKS00006350) is its focus on the multivariate associations between these aspects and their consecutive significance regarding treatment satisfaction (TS) in peritoneal dialysis (PD) versus haemodialysis (HD) patients. In this article, we present the baseline results of a multicentre study, which is supported by a grant from the German Ministry for Education and Research. Six to 24 months after initiation of dialysis, 780 patients from 55 dialysis centres all over Germany were surveyed. The questionnaire addressed psychosocial, physical, socio-demographic and shared decision-making (SDM) aspects. Furthermore, cognitive functioning was tested. After indexing the measures, two propensity score-matched groups (n = 482) were compared in a first step, after having chosen PD or HD. In a second step, a moderated multiple regression (n = 445) was conducted to initially investigate the multivariate impact of patient characteristics on TS. In comparison with HD patients, PD patients were more satisfied with their treatment (P < 0.001), had a more autonomy-seeking personality (P = 0.04), had better cognitive functioning (P = 0.001), indicated more satisfying SDM (P < 0.001) and had a larger living space (P < 0.001). All patients were more satisfied when they had a good psychological state and received SDM. Especially in HD patients, TS was higher when the patient had a less autonomous personality, lower cognitive functioning, more social support, a poorer physical state and poorer socio-demographic conditions (R2 = 0.26). Psychosocial characteristics play a major role in TS in dialysis patients. Within a multivariate approach, these factors are even more important than physical or environment-related factors. In practice, focusing on SDM and screening patient characteristics at an early stage can foster patients’ TS. Changes will be examined in a 1-year follow-up.

On the field-antifield (a)symmetry of the pure spinor superstring

In this work, the DDF-like approach to the pure spinor cohomology is extended to the next ghost number level, the so called antifields. In a direct (supersymmetric) parallel to the bosonic string, some properties of the ghost number two cohomology are derived with the enlargement of the DDF algebra. Also, the DDF conjugates of the b ghost zero mode emerge naturally from the extended algebra and the physical state condition is discussed. Unlike the bosonic string case, the cohomology analysis of the pure spinor b ghost is restricted to BRST-closed states.

New multi-physics approach for modelling and design of alkaline electrolyzers

This work presents a multi-physics model used for the design and diagnosis of the alkaline electrolyzers. The model is based on a new approach that allows to choose precisely the design parameters of a new electrolyzer even if it is not commercially available and predicting energy consumption, efficiency and rate of hydrogen production, taking into account to their physical state and various operating conditions. The approach differs from those of conventional models of the following: It allows the characterization of the electrolyzer based on its structural parameters in a relatively short time (few minutes) compared with the conventional approach which need experimental data collected for few weeks (Ulleberg). The approach allows describing a range of alkaline electrolyzers, while semi-empirical models found in literature are inherent to a specific electrolyzer. In addition, the model takes into account the variation of all structural parameters (geometry, materials and their evolution depending on operating conditions) and operational parameters of the electrolyzer (temperature, pressure, concentration, bulk bubbling and recovery rate of electrode surface by the bubble), while the models in the literature involve only the temperature. The developed multi-physics model was programmed in a Matlab Simulink® environment and an alkaline electrolyzer’s simulation tool was developed. The simulation tool was validated using two industrial (Stuart and Phoebus) electrolyzers with different structures and power rates. Simulation results reproduced experimental data with good accuracy (less than 0.9%). The simulation tool was also used to compare the energy efficiency of two hydrogen production systems. The first one is based on atmospheric electrolyzer with a compressor for hydrogen storage and the second one is a barometric electrolyzer (under pressure) with its auxiliary devices to identify the effective mode of hydrogen production according to the physical state and operating conditions of the electrolyzer. The analysis of results revealed that the second mode of hydrogen production is more efficient and confirms the results of the literature based solely on the thermodynamic approach (K. Onda et al) without the input of the power consumed by power overvoltages.

MODELING M-THEORY VACUA VIA GAUGED S-DUALITY

We construct a model of M-theory vacua using gauged S-duality and the Chan–Paton symmetries by introducing an infinite number of open string charges. In the Bechi–Rouet–Stora–Tyutin formalism, the local description of the gauged S-duality on its moduli space of vacua is fully determined by one physical state condition on the vacua. We introduce the string probe of the spatial degrees of freedom and define the increment of the cosmic time. The dimensionality of space–time and the gauge group of the low energy effective theory originate in the symmetries (with or without their breakdown) in our model. This modeling leads to the derived category formulation of the quantum mechanical world including gravity and to the concept of a nonlinear potential of gauged and affinized S-duality which specifies the morphism structure of this derived category.

THE ORBIFOLD-STRING THEORIES OF PERMUTATION-TYPE II: CYCLE DYNAMICS AND TARGET SPACE–TIME DIMENSIONS

We continue our discussion of the general bosonic prototype of the new orbifold-string theories of permutation-type. Supplementing the extended physical-state conditions of the previous paper, we construct here the extended Virasoro generators with cycle central charge [Formula: see text], where fj(σ) is the length of cycle j in twisted sector σ. We also find an equivalent, reduced formulation of each physical-state problem at reduced cycle central charge cj(σ) = 26. These tools are used to begin the study of the target space–time dimension [Formula: see text] of cycle j in sector σ, which is naturally defined as the number of zero modes (momenta) of each cycle. The general model-dependent formulae derived here will be used extensively in succeeding papers, but are evaluated in this paper only for the simplest case of the "pure" permutation orbifolds.

The orbifold-string theories of permutation-type: I. One twisted BRST per cycle per sector

We resume our discussion of the new orbifold-string theories of permutation-type, focusing in the present series on the algebraic formulation of the general bosonic prototype and especially the target space-times of the theories. In this first paper of the series, we construct one twisted BRST system for each cycle $j$ in each twisted sector $\sigma$ of the general case, verifying in particular the previously-conjectured algebra $[Q_{i}(\sigma),Q_{j}(\sigma)]_{+} =0$ of the BRST charges. The BRST systems then imply a set of extended physical-state conditions for the matter of each cycle at cycle central charge $\hat{c}_{j}(\sigma)=26f_{j}(\sigma)$ where $f_{j}(\sigma)$ is the length of cycle $j$.

Relativistic Particle in Complex Spacetime

A modified version of the bilocal particle is presented in terms of complex spacetime. Unusual constraint structure of the model is studied, and a new concept of the physical equivalence is proposed in accordance with Dirac's conjecture. It is found that in the quantum theory the physical state conditions are compatible with existence of eigenstates of momentum only when the dimension of spacetime is four. An example of scattering amplitude is calculated.

Nonlinear completion of massive gravity of the Fierz-Pauli type

A possible nonlinear completion of massive gravity of the Fierz-Pauli type is proposed. The theory describes a system consisting of a massive tensor field of the Fierz-Pauli type and an additional massive vector field. Massless limit as well as flat-spacetime limit can be taken smoothly. Constructing a nonlinear version of the physical-state condition which drives an extra scalar ghost from physical states is still unsettled.

Physical state condition in quantum general relativity as a consequence of BRST symmetry

Quantization of systems with constraints can be carried out with several methods. In the Dirac formulation the classical generators of gauge transformations are required to annihilate physical quantum states to ensure their gauge invariance. Carrying on BRST symmetry it is possible to get a condition on physical states which, different from the Dirac method, requires them to be invariant under the BRST transformation. Employing this method for the action of general relativity expressed in terms of the spin connection and tetrad fields with path integral methods, we construct the generator of the BRST transformation associated with the underlying local Lorentz symmetry of the theory and write a physical state condition following from BRST invariance. This derivation is based on the general results on the dependence of the effective action used in path integrals and consequently of Green's functions on the gauge-fixing functionals used in the DeWitt–Faddeev–Popov method. The condition we gain differs from the one obtained within Ashtekar's canonical formulation, showing how we recover the latter only by a suitable choice of the gauge-fixing functionals. Finally we discuss how it should be possible to obtain all of the requested physical state conditions associated with all the underlying gauge symmetries of the classical theory using our approach.