bluuebunny/crossref_metadata_2025 huggingface dataset:
Extrapolating evidence for molecularly targeted therapies from common to rare cancers: a scoping review of methodological guidance
Authors: Cho Doah , Cheyne Saskia , Lord Sarah J , Simes John , Lee Chee Khoon
Published: July 2022

Objectives

Cancer is increasingly classified according to biomarkers that drive tumour growth and therapies developed to target them. In rare biomarker-defined cancers, randomised controlled trials to adequately assess targeted therapies may be infeasible. Extrapolating existing evidence of targeted therapy from common cancers to rare cancers sharing the same biomarker may reduce evidence requirements for regulatory approval in rare cancers. It is unclear whether guidelines exist for extrapolation. We sought to identify methodological guidance for extrapolating evidence from targeted therapies used for common cancers to rare biomarker-defined cancers.

Design

Scoping review.

Data sources

Websites of health technology assessment agencies, regulatory bodies, research groups, scientific societies and industry. EBM Reviews—Cochrane Methodology Register and Health Technology Assessment, Embase and MEDLINE databases (1946 to 11 May 2022).

Eligibility criteria

Papers proposing a framework or recommendations for extrapolating evidence for rare cancers, small populations and biomarker-defined cancers.

Data extraction and synthesis

We extracted framework details where available and guidance for components of extrapolation. We used these components to structure and summarise recommendations.

Results

We identified 23 papers. One paper provided an extrapolation framework but was not cancer specific. Extrapolation recommendations addressed six distinct components: strategies for grouping cancers as the same biomarker-defined disease; analytical validation requirements of a biomarker test to use across cancer types; strategies to generate control data when a randomised concurrent control arm is infeasible; sources to inform biomarker clinical utility assessment in the absence of prospective clinical evidence; requirements for surrogate endpoints chosen for the rare cancer; and assessing and augmenting safety data in the rare cancer.

Conclusions

In the absence of an established framework, our recommendations for components of extrapolation can be used to guide discussions about interpreting evidence to support extrapolation. The review can inform the development of an extrapolation framework for biomarker-targeted therapies in rare cancers.
Comparison of fracture risk calculators in elderly fallers: a hospital-based cross-sectional study
Authors: Todorov Georgi , Brook Susan , Quah Qin Xian Nicole , Von Widekind Sophia , Freudenthal Bernard , Comninos Alexander N
Published: July 2022

Objective

Elderly patients presenting with falls are known to carry an extremely high risk of future fragility fractures. Current osteoporosis guidelines recommend using fracture risk calculators such as FRAX, QFracture or Garvan to guide management. However, they differ considerably in their inputs and may therefore provide contrasting risk estimations in certain individuals. In this study, we compare these risk calculators in a high-risk cohort of elderly patients admitted to hospital with falls.

Design

Hospital-based cross-sectional study.

Setting

Secondary care, London, UK.

Participants

Data from 120 consecutive elderly patients who had falls presenting to a single hospital over 4 months were collected. 10-year major and hip fracture risks were calculated using FRAX, QFracture and Garvan. 1-year major and hip fracture risks from QFracture were assessed against prospective incidence of fracture.

Results

Median 10-year major fracture risk was: FRAX 19.5%, QFracture 26.0%, Garvan 32.5%. Median 10-year hip fracture risk was: FRAX 9.6%, QFracture 21.1%, Garvan 6.5%. Correlation between FRAX and QFracture was r=0.672 for major, r=0.676 for hip fracture (both p<0.0001); FRAX and Garvan r=0.778 (p<0.0001) for major, r=0.128 (p=0.206) for hip fracture; QFracture and Garvan r=0.658 (p<0.0001) for major, r=0.318 (p<0.001) for hip fracture. QFracture 1-year predicted major and hip fracture rates were 1.8% and 1.2%, respectively, compared with actual rates of 2.1% and 0%, respectively.

Conclusions

Although strong correlations between calculators were observed in the study cohort, there were differences of up to 13% between estimated risks. QFracture captured several elderly-specific inputs not considered by other calculators and so projected higher fracture risk than the other calculators. QFracture provided 1-year fracture risks that were comparable with the prospective observed fracture incidence in the cohort. This study has important clinical implications for the use of fracture risk calculators to guide treatment decisions, particularly in the high-risk cohort of elderly patients admitted to hospital following falls.
Effect of HEAT therapy in patiEnts with type 2 Diabetes mellitus (HEATED): protocol for a randomised controlled trial
Authors: Sebők Judit , Édel Zsófia , Dembrovszky Fanni , Farkas Nelli , Török Zsolt , Balogh Gábor , Péter Mária , Papp Ildiko , Balogi Zsolt , Nusser Nóra , Péter Iván , Hooper Philip , Geiger Paige , Erőss Bálint , Wittmann István , Váncsa Szilárd , Vigh László , Hegyi Péter
Published: July 2022

Introduction

The burden of type 2 diabetes mellitus (T2DM) is increasing worldwide. Heat therapy has been found effective in improving glycaemic control. However, to date, there is a lack of randomised controlled studies investigating the efficacy of heat therapy in T2DM. Therefore, we aim to investigate whether heat therapy with natural thermal mineral water can improve glycaemic control in patients with T2DM.

Methods and analysis

The HEAT therapy in patiEnts with type 2 Diabetes mellitus (HEATED) Study is a single-centre, two-arm randomised controlled trial being conducted at Harkány Thermal Rehabilitation Centre in Hungary. Patients with T2DM will be randomly assigned to group A (bath sessions in 38°C natural thermal mineral water) and group B (baths in thermoneutral water (30°C–32°C)). Both groups will complete a maximum of 5 weekly visits, averaging 50–60 visits over the 12-week study. Each session will last 30 min, with a physical check-up before the bath. At baseline, patients’ T2DM status will be investigated thoroughly. Possible microvascular and macrovascular complications of T2DM will be assessed with physical and laboratory examinations. The short form-36 questionnaire will assess the quality of life. Patients will also be evaluated at weeks 4, 8 and 12. The primary endpoint will be the change of glycated haemoglobin from baseline to week 12. An estimated 65 patients will be enrolled per group, with a sample size re-estimation at the enrolment of 50% of the calculated sample size.

Ethics and dissemination

The study has been approved by the Scientific and Research Ethics Committee of the Hungarian Medical Research Council (818-2/2022/EÜIG). Written informed consent is required from all participants. We will disseminate our results to the medical community and will publish our results in peer-reviewed journals.

Trial registration number

ClinicalTrials.gov, NCT05237219.
Constraining the $${\mathcal {C}}{\mathcal {P}}$$ structure of Higgs-fermion couplings with a global LHC fit, the electron EDM and baryogenesis
Authors: Bahl Henning , Fuchs Elina , Heinemeyer Sven , Katzy Judith , Menen Marco , Peters Krisztian , Saimpert Matthias , Weiglein Georg
Published: July 2022

$${\mathcal {C}}{\mathcal {P}}$$

C
P

violation in the Higgs couplings to fermions is an intriguing, but not yet extensively explored possibility. We use inclusive and differential LHC Higgs boson measurements to fit the $${\mathcal {C}}{\mathcal {P}}$$

C
P

structure of the Higgs Yukawa couplings. Starting with simple effective models featuring $${\mathcal {C}}{\mathcal {P}}$$

C
P

violation in a single Higgs–fermion coupling, we probe well-motivated models with up to nine free parameters. We also investigate the complementarity of LHC constraints with the electron electric dipole moment bound, taking into account the possibility of a modified electron Yukawa coupling, and assess to which extent $${\mathcal {C}}{\mathcal {P}}$$

C
P

violation in the Higgs–fermion couplings can contribute to the observed baryon asymmetry of the universe. Even after including the recent analysis of angular correlations in $$H\rightarrow \tau ^+\tau ^-$$

H
→

τ
+

τ
-

decays, we find that a complex tau Yukawa coupling alone may be able to account for the observed baryon asymmetry, but with large uncertainties in the baryogenesis calculation. A combination of complex top and bottom quark Yukawa couplings yields a result four times larger than the sum of their separate contributions, but remains insufficient to account for the observed baryon asymmetry.
Weyl cosmology
Authors: Berezin V. A. , Dokuchaev V. I.
Published: July 2022

The homogeneous and isotropic cosmological model in the Weyl conformal geometry is considered. We showed that, despite the conformal invariance, the dust matter is allowed in such a universe. It is shown that the number of dust particles is not conserved, i.e. they are continuously produced. The general form of the law for their creation is found.
Stochastic processes in the space of random joint events and equations for transition probabilities of quantum systems
Authors: Biryukov A. A.
Published: July 2022

A model of the space of random joint events is constructed. In the space, along with the existence of a symmetric difference of joint events, a new postulate about the existence of a symmetric sum of random joint events is introduced. In the generated space, a stochastic equation of the system motion and an equation for the probabilities of the system transition between two events are constructed. The probability of transition depends on the probabilities of compatibility of two, three, etc. events. The equation is equivalent to the equation of quantum theory if the events are compatible only in pairs. The proposed equation for incompatible events passes into the equation of the Markov chain.
Neutron physics investigations of fundamental processes of statistical mechanics
Authors: Dzheparov F. S. , Gulko A. D. , Elyutin N. O. , Lvov D. V. , Shestopal V. E.
Published: July 2022

Studies in spin dynamics of disordered media and multiple ultra-small angle neutron scattering are considered. The experiments were carried out on unique installations designed in ITEP laboratory of neutron physics: beta-NMR spectrometer and universal neutron diffractometer. The main attention is paid to random walks in disordered systems and ultra-small angle neutron scattering (USANS) on objects with space correlations in positions of scatterers. Synthesis of concentration expansion, semi-phenomenological theory and numerical simulations produced satisfactory description of the nuclear polarization transfer within disordered 8Li–6Li spin subsystem in LiF single crystal. The theory of USANS starts from eikonal approximation for the scattering amplitude, which (a) reproduces the phenomenological Moliere–Bethe theory for the observable neutron angular distributions for uncorrelated random positions of scatterers, and (b) gives a possibility to take into account their spatial correlations.
Chaotic RF Generator for Sub-1-GHz Chaos-Based Communication Systems: Mathematical Modeling and Experimental Validation
Authors: Messaadi Moundher , Sadoudi Said , Ouslimani Achour , Teguig Djamal , Bendecheche Hichem
Published: July 2022

In this paper, we have studied, designed and realized a single-transistor chaotic generator with a smooth power spectrum of about −35 dBm in frequency bandwidth up to 1 GHz. The chaos generator model is described by a continuous-time six-dimensional autonomous system assuming an exponential nonlinearity. Chaotic behavior is characterized by bifurcation diagrams, Lyapunov exponents, phase portraits of the attractors and spectra of the oscillations, using both numerical and circuit simulations. Advanced Design System (ADS)-based simulations were carried out to support the theoretical analysis, and to validate the mathematical model. The simulations are carried out using real transistor parameters and taking into account the properties of the substrate, the influence of the board topology and the characteristics of the layout material. This simulation method known as EM/Circuit Co-Simulation allows the simulation results to approach as closely as possible to those of the experiments. In the light of the positive simulation results, the proposed structure is realized to demonstrate its feasibility, and to confirm the numerical results. The prototype is manufactured and mounted on a breadboard using the surface-mount devices and BFP193 bipolar junction transistor. After realizing the generator, we pushed it further towards perfection, through the proposal and realization of a broadband amplifier, in order to gain more bandwidth to improve the spectral characteristic of the generator, which makes it promising for many communication applications such as spread spectrum communication, direct chaotic communication, etc.
Cooperative Autonomous Driving for Urban Intersections Assisted by Vehicular Sensor Networks
Authors: Zhou Momiao , Wang Pengcheng , Ding Zhizhong , Liu Zhengqiong , Niu Jian , Shen Jie , He Liu
Published: July 2022

The current autonomous driving vehicles cannot collaborate with each other due to the disconnection of sensors between vehicles, which leads to poor performance in traffic efficiency and safety. Recently, with the development of wireless intelligent sensors, vehicular sensor network (VSN) is emerging to provide information sharing between vehicles, so that cooperative autonomous driving (CAD) can be enabled. This paper especially investigates the VSN-assisted straight-going CAD at urban intersections under the rule of traffic signals. First, the function of VSN is presented, and the information sharing mechanism is designed. Then distributed stop-and-go strategies with maintaining the optimal safety spacing between adjacent vehicles are proposed for multiple traffic cases. With the proposed strategies, every vehicle can get an exact time to decelerate or accelerate at signalized intersections. Finally, we use the model predictive control (MPC) scheme to actuate our strategies, and it is demonstrated that vehicles perform well in both passage safety and efficiency as expected.
Improving Large-Gap Clone Detection Recall Using Multiple Features
Authors: Dai Peng , Zhang Qianjin , Wang Yawen , Jin Dahai , Gong Yunzhan
Published: July 2022

Code clone refers to two or more identical or similar source code fragments. Research on code clone detection has lasted for decades. Investigation and evaluation of existing clone detection techniques indicate that they are resilient to function-level clone detection. Still, there may be room for further research in block-level clone detection. Particularly, type-3 clones that include large gaps, are ongoing challenges. To solve these problems, we propose a clone detection method based on multiple code features. It aims to improve the recall rate of code block clone detection and overcome large-gap and hard-to-detect type-3 clones. This method first splits the source code files based on the program’s structural features and context features to obtain code blocks. The collection of code blocks obtained in this way is complete, and the large gaps in clone pairs will also be removed. In addition, we only need to compute the similarity between code blocks with the same structural features, which can also significantly save time and resources. The similarity is obtained by calculating the proportion of the same tokens between two code blocks. Moreover, since different types of tokens have different weights in similarity calculation, we use supervised learning to obtain a classifier model between token features and code clone. We divide the tokens into 13 types and train the machine learning model with the manually confirmed clone or non-clone pair. Finally, we develop a prototype system and compare our tools with existing tools under the Mutation Framework and in several actual C projects. The experimental results also demonstrate the advancement and practicality of our prototype.
Shape coexistence and possible isomers in 117Sn
Authors: Bai H. F. , Wang S. Y. , Xu W. Z. , Zhu L. H. , Wu X. G. , Sun D. P. , Liu C. , Li Z. Q. , Jia H. , Qi B. , Li G. S. , Wang S. , Guo R. J. , Han X. C. , Xiao X. , Mu L. , He C. Y. , Zheng Y. , Wang X. D. , Zhu L. , Li Y. J. , Liu L.
Published: July 2022

Excited states of 117Sn have been populated using the fusion-evaporation reaction 114Cd(7Li, 1p3n) at a beam energy of 48[Formula: see text]MeV. A total of nine new transitions have been identified and added into the level scheme of 117Sn. Based on the systematical comparisons with the neighboring Sn isotopes and the configuration-fixed constrained triaxial relativistic mean-field (RMF) calculations, a collective structure and two isomers are proposed to exist in 117Sn. The phenomenon of shape coexistence has been extended to A = 117 in odd-A Sn isotopes for the first time.
A FINITE SUM INVOLVING GENERALIZED FALLING FACTORIAL POLYNOMIALS AND DEGENERATE EULERIAN POLYNOMIALS
Authors: KIM TAEKYUN , KIM DAE SAN , PARK JIN-WOO , BOULAARAS SALAH MAHMOUD
Published: July 2022

The aim of this paper is two-fold. First, we investigate a finite sum involving the generalized falling factorial polynomials, in some special cases of which we express it in terms of the degenerate Stirling numbers of the second kind, the degenerate Bernoulli polynomials and the degenerate Frobenius–Euler polynomials. Second, we consider the degenerate Eulerian polynomials and deduce the generating function and a recurrence relation for them.
SOME RESULTS ON r-TRUNCATED DEGENERATE POISSON RANDOM VARIABLES
Authors: KIM TAEKYUN , KIM DAE SAN , PARK JIN-WOO , LEE SI-HYEON , PARK SEONG-HO , ALQAWBA MOHAMMED SULAIMAN , JANG LEE-CHAE
Published: July 2022

The zero-truncated Poisson distributions are certain discrete probability distributions whose supports are the set of positive integers, which are also known as the conditional Poisson distributions or the positive Poisson distributions. Recently, as a natural extension of those distributions, Kim–Kim studied the zero-truncated degenerate Poisson distributions. In this paper, we introduce the [Formula: see text]-truncated degenerate Poisson random variable with parameter [Formula: see text], whose probability mass function is given by [Formula: see text], and investigate various properties of this random variable.
ANALYSIS OF THE TRANSMISSION OF NIPAH VIRUS UNDER FRACTIONAL OPERATOR WITH NON-SINGULAR AND NONLOCAL KERNEL
Authors: ALI ARSHAD , YOUSEF ALI , ULLAH AMAN , AHMAD SHABIR , NAZ HAFSA , AL-MDALLAL QASEM M.
Published: July 2022

The fractional dynamics of the lethal Nipah virus (NiV) is investigated in this research. The transmission patterns of the Nipah virus are studied quantitatively and qualitatively. Fixed-point results are utilized to study the NiV fractional model qualitatively. An efficient numerical method Predictor–Corrector (PC) is used to deduce the numerical results of the NiV model. The stability of the numerical approach is studied through nonlinear analysis. The numerical results are graphically presented in various fractional orders. The effects of transmission and infection rates on the evolution of the proposed model are presented through numerical simulations.
THE GUAVA MODEL INVOLVING THE CONFORMABLE DERIVATIVE AND ITS MATHEMATICAL ANALYSIS
Authors: HOSSEINI KAMYAR , SADRI KHADIJEH , MIRZAZADEH MOHAMMAD , SALAHSHOUR SOHEIL , PARK CHOONKIL , LEE JUNG RYE
Published: July 2022

A nonclassical model known as the guava model with the conformable derivative describing the interaction of guava pests and natural enemies is studied in this paper. To this end, first the Adams–Bashforth–Moulton predictor–corrector (ABM-PC) scheme is adopted to numerically solve the guava model with the conformable derivative such that its performance is examined using the finite-difference (FD) method. The truncation error of the ABM-PC scheme is then presented in a detailed way. The effect of the order of the conformable derivative on the dynamical characteristics of guava pests and natural enemies is investigated by considering a series of graphical representations. In the end, based on the results given in this study, it is shown which day is more beneficial to harvest the guava.
NOTES ON CONFORMAL PERTURBATION OF HEAT KERNELS
Authors: ZHAO SHILIANG
Published: July 2022

Let [Formula: see text] be a smooth n-dimensional Riemannian manifold for [Formula: see text]. Consider the conformal perturbation [Formula: see text] where [Formula: see text] is a smooth bounded positive function on [Formula: see text]. Denote by [Formula: see text] the Laplace–Beltrami operator of manifold [Formula: see text]. In this paper, we derive the upper bounds of the heat kernels for [Formula: see text] with [Formula: see text]. Moreover, we also investigate the gradient estimates of the heat kernel for [Formula: see text].
NONEXISTENCE RESULTS FOR A CLASS OF NONLINEAR FRACTIONAL DIFFERENTIAL INEQUALITIES INVOLVING ERDÉLYI–KOBER FRACTIONAL DERIVATIVES
Authors: ALAZMAN IBTEHAL , JLELI MOHAMED , SAMET BESSEM
Published: July 2022

A class of Erdélyi–Kober fractional differential inequalities with a polynomial nonlinearity and a singular potential function is investigated in this paper. By mean of the test function method, we establish sufficient conditions for the nonexistence of global weak solutions. Some examples are provided to illustrate our obtained results. To the best of our knowledge, the issue of nonexistence of global solutions for fractional differential equations or inequalities, involving Erdélyi–Kober fractional derivatives, was never addressed in the literature.
ON HIGHLY EFFICIENT SIMULTANEOUS SCHEMES FOR FINDING ALL POLYNOMIAL ROOTS
Authors: SHAMS MUDASSIR , RAFIQ NAILA , KAUSAR NASREEN , AGARWAL PRAVEEN , MIR NAZIR AHMAD , LI YONG-MIN
Published: July 2022

This paper develops optimal family of fourth-order iterative techniques in order to find a single root and to generalize them for simultaneous finding of all roots of polynomial equation. Convergence study reveals that for single root finding methods, its optimal convergence order is 4, while for simultaneous methods, it is 12. Computational cost and numerical illustrations demonstrate that the newly developed family of methods outperformed the previous methods available in the literature.
ON q-DERANGEMENT NUMBERS AND POLYNOMIALS
Authors: KIM TAEKYUN , KIM DAE SAN , KIM HYE KYUNG
Published: July 2022

The derangement number [Formula: see text] is the number of fixed point free permutations on a set of [Formula: see text] elements and the derangement polynomial [Formula: see text]) is a natural extension of the derangement number [Formula: see text]. The aim of this paper is to introduce [Formula: see text]-derangement numbers and polynomials, which are [Formula: see text]-analogs of the derangement numbers and polynomials, and to investigate their connection with some other [Formula: see text]-special numbers and polynomials. In more detail, we derive explicit expressions and recurrence relations for the [Formula: see text]-derangement numbers and polynomials. Further, we obtain some identities involving such polynomials and numbers and other special [Formula: see text]-polynomials and numbers, which include [Formula: see text]-Bell polynomials, [Formula: see text]-analogs of Fubini polynomials and [Formula: see text]-Stirling numbers of the second kind.
THERMAL SPRAYING AND RELATED TECHNOLOGIES FOR THE SURFACE MODIFICATION OF AL ALLOYS: REVIEW
Authors: SAHOO BAIDEHISH , DAS TANMOY , PAUL JINU
Published: July 2022

Aluminum (Al) and its alloys are attractive for a variety of applications due to its advantages like light weight, ease of processing, and high thermal/electrical conductivities. However, it suffers short comings in terms of strength, wear resistance, and corrosion resistance. Thermal spray processes are widely used techniques for the surface property improvement like thermal, wear, and corrosion resistances of aluminum and other light metals. This paper summarizes the recent developments in thermal spraying and related technologies. Plasma spraying, flame spraying, and arc spraying are the chief thermal spraying techniques, whereas the HVOF and D-gun processes are the derivatives of flame spraying process. The cold spraying technique is an emerging coating technique where the particles are heated to a temperature lower than their melting point travel at high velocity and coat on impact with the target material by plastic deformation. Different parameters like heat source characteristics, coating material properties, substrate properties, and spray torch operating circumstances affect the coating microstructure and properties.
INVESTIGATION OF SURFACE PROPERTIES AND FeB-Fe2B LAYER FORMATION IN PACK BORONIZING OF CEMENTATION STEEL
Authors: TEKER TANJU , SARI MURAT
Published: July 2022

In this study, cementation steel was boronized at 1050∘C for 6[Formula: see text]h, 8[Formula: see text]h, and 10[Formula: see text]h. Microstructural change on the surface of the samples after boronization was detected by optical microscope (OM), scanning electron microscope (SEM), energy dispersive spectroscopy (EDS), X-Ray diffraction (XRD), and electron back scatter diffraction (EBSD) analyses. Also, surface roughness, microhardness, and layer thickness were measured. FeB, Fe2B phases, and saw tooth morphology expected in iron-based metals during boring process occurred in the entire process time. The average layer thickness of the boronized samples at 1050∘C for 10[Formula: see text]h was measured as 222[Formula: see text][Formula: see text]m and the surface roughness value was 3.40[Formula: see text][Formula: see text]m. The hardness of boride phases acquired on the samples varied between 1700 HV and 1730 HV. As a result, while the ratio of chromium carbide is the highest in the base metal, the boron level was the highest in the coating. Compounds 49[Formula: see text]wt.% Cr7C3 and 47[Formula: see text]wt.% B were identified as the most intensely concentrated.
MICROSTRUCTURE AND TRIBOLOGICAL PERFORMANCE OF SELF-LUBRICATE CLADDING PRODUCED BY TUNGSTEN INERT GAS AND MICROWAVE HYBRID HEATING TECHNIQUES
Authors: SURESH G. , RAMESH M. R. , SHANMUGAM N. SIVA , SRINATH M. S.
Published: July 2022

The wear reduction of moving components is highly desirable because wear limits their reliability and service life, mainly at elevated temperatures. This study produced thick clads of NiCrSiB/WC/MoS2/BaF2 by tungsten inert gas (TIG) and microwave hybrid heating (MHH) cladding techniques, which were compared for microstructural and high-temperature tribological properties. The clad samples were subjected to sliding contact using a pin on disc tribometer at 200∘C, 400∘C, 600∘C under 20 and 40[Formula: see text]N load. The worn surface was analyzed using FESEM, XRD and three-dimensional (3D) profilometer. The experimental results revealed a significant effect of the TIG current and MHH exposure time on the microhardness value, which predominantly depends on the morphological characteristics. The average hardness of TIG clads was found to be 1.2 times higher than the MHH clad. Because of the MoS2 and BaF2 encapsulation, the continuous lubricant layer formation compensated for improved wear resistance with good reliability and longer service life. This work provides significant insights into the wear behavior of TIG and MHH clads at elevated temperatures and the prospective applications in turbines, where inadequate wear resistance of titanium alloy is the major concern for its use.
MULTIVARIATE DYNAMIC CASH SUB-ADDITIVE RISK MEASURES FOR PROCESSES
Authors: SUN FEI , LUO KUI , FENG YU
Published: July 2022

In this paper, we study a new class of dynamic risk measures for processes. These new risk measures are derived for the portfolio vectors and adapted to a given filtration. By introducing the notion of discount factor, we deeply analyze the property of cash sub-additivity for these risk measures. Furthermore, by expanding the risk position space, we derive the relationship between these new risk measures and the dynamic convex risk measures introduced by Wei & Hu [(2014) Coherent and convex risk measures for portfolios with applications, Statistics & Probability Letters 90, 114–120]. At last, we establish the representation results for them by making full use of the relationship.
A STOCHASTIC CONTROL APPROACH TO BID-ASK PRICE MODELLING
Authors: DELA VEGA ENGEL JOHN C. , ELLIOTT ROBERT J.
Published: July 2022

This paper develops a model for the bid and ask prices of a European-type asset by formulating a stochastic control problem. The state process is governed by a modified geometric Brownian motion whose drift and diffusion coefficients depend on a Markov chain. A Girsanov theorem for Markov chains is implemented for the change of coefficients, including the diffusion coefficient which cannot be changed by the usual Girsanov theorem for Brownian motion. The price of a European-type asset is then determined using an Esscher transform and a system of partial differential equations. A dynamic programming principle and a maximum/minimum principle associated with the stochastic control problem are then derived to model bid and ask prices. These prices are not quotes of traders or market makers but represent estimates in our model on which reasonable quantities could be traded.
Rethinking Optimum Currency Area in East and South-East Asia: New Empirical Evidence
Authors: Sharma Chandan , Khanna Rupika
Published: July 2022

This paper evaluates the viability of a monetary union or optimum currency area (OCA) in East and South-East Asia. Previous studies have mainly focused on a single aspect of integration, which has led to contrary findings. We adopt several alternative approaches that cover fiscal, output, and price aspects to accomplish the objective. As the synchronization of business cycle is a key prerequisite for forming an OCA, we test the level of business cycle synchronization among the countries of this region. The results of synchronization testing appear favorable, thus, strengthening the argument for forming a monetary union. Our analysis also shows that the regional shock is a dominating factor determining output movements in these countries. Next, we use a generalized purchasing power parity (G-PPP) procedure to test the long-run interrelationship among bilateral real exchange rates. Our findings based on bilateral real exchange rates indicate that the vital macroeconomic variables that determine real exchange rates, such as trade, finance, and price movements, are highly associated in the region. We also find that the short-run adjustment speed is sufficiently large for most exchange rates, barring a few. Consequently, we show that most economies in the region are sufficiently integrated to form a monetary union at any time.
Does the Firm with Well-Educational Level of Board Members Have Good Corporate Governance?
Authors: Hung Shih-Wei , Hsiao Hsing-Chin , Wang Jan-Chung
Published: July 2022

This study examined the degree to which the educational level of directors affects corporate governance and firm value in firms. From the results, it has been found that the educational levels of directors are negatively related to corporate governance performance. On the other hand, firms with higher-educated directors have lower block shareholders’ holdings, which implies that the ownership right is not concentrated and block shareholders cannot effectively monitor the operation of the firm to avoid agency problems. Furthermore, a firm with higher educational levels of directors and stronger governance mechanisms is more significant to raise the firm value.
The prime submodules hypergraph of a free module of finite rank over a commutative ring
Authors: Mirzaei F. , Nekooei R.
Published: July 2022

Let [Formula: see text] be a commutative ring with identity, [Formula: see text] be a prime ideal of [Formula: see text] and [Formula: see text] be a free [Formula: see text]-module of finite rank. In this paper, we use hypergraphs to give a full characterization of prime submodules of [Formula: see text]. Also we define a hypergraph [Formula: see text] called the prime submodules hypergraph of [Formula: see text] with respect to [Formula: see text] and use properties of Steiner systems for counting the number of [Formula: see text]-prime submodules of [Formula: see text] when the number of cosets of [Formula: see text] in [Formula: see text] is finite.
On representations induced from the Zelevinsky segment and a tempered representation in the half-integral case
Authors: Matić Ivan
Published: July 2022

Let [Formula: see text] denote either the group [Formula: see text] or [Formula: see text] over a non-archimedean local field of characteristic zero. We determine the reducibility criteria for a parabolically induced representation of the form [Formula: see text], where [Formula: see text] denotes the Zelevinsky segment representation of the general linear group attached to the segment [Formula: see text], with [Formula: see text] half-integral, and [Formula: see text] denotes an irreducible tempered representation of [Formula: see text].
Gorenstein homogeneous subrings of graphs
Authors: Cruz Lourdes , Reyes Enrique , Toledo Jonathan
Published: July 2022

Let [Formula: see text] be a connected simple graph, with [Formula: see text] vertices whose homogeneous monomial subring is [Formula: see text]. We prove that if [Formula: see text] is normal and Gorenstein, then [Formula: see text] is unmixed with cover number [Formula: see text] and [Formula: see text] has a strong [Formula: see text]-[Formula: see text]-reduction. Also, if [Formula: see text] is normal and [Formula: see text] is unmixed whose cover number is [Formula: see text], we give sufficient conditions for [Formula: see text] to be Gorenstein.
TemporalGSSA: A numerically robust R-wrapper to facilitate computation of a metabolite-specific and simulation time-dependent trajectory from stochastic simulation algorithm (SSA)-generated datasets
Authors: Kundu Siddhartha
Published: July 2022

Whilst data on biochemical networks has increased several-fold, our comprehension of the underlying molecular biology is incomplete and inadequate. Simulation studies permit data collation from disparate time points and the imputed trajectories can provide valuable insights into the molecular biology of complex biochemical systems. Although, stochastic simulations are accurate, each run is an independent event and the data that is generated cannot be directly compared even with identical simulation times. This lack of robustness will preclude a biologically meaningful result for the metabolite(s) of concern and is a significant limitation of this approach. “TemporalGSSA” or temporal Gillespie Stochastic Simulation Algorithm is an R-wrapper which will collate and partition SSA-generated datasets with identical simulation times (trials) into finite sets of linear models (technical replicates). Each such model (time step of a single run, absolute number of molecules for a metabolite) computes several coefficients (slope, intercept, etc.). These coefficients are averaged (mean slope, mean intercept) across all trials of a technical replicate and along with an imputed time step (mean, median, random) is incorporated into a linear regression equation. The solution to this equation is the number of molecules of a metabolite which is used to compute the molar concentration of the metabolite per technical replicate. The summarized (mean, standard deviation) data of this vector of technical replicates is the outcome or numerical estimate of the molar concentration of a metabolite and is dependent on the duration of the simulation. If the SSA-generated dataset comprises runs with differing simulation times, “TemporalGSSA” can compute the time-dependent trajectory of a metabolite provided the trials-per technical replicate constraint is complied with. The algorithms deployed by “TemporalGSSA” are rigorous, have a sound theoretical basis and have contributed meaningfully to our comprehension of the mechanism(s) that drive complex biochemical systems. “TemporalGSSA”, is robust, freely accessible and easy to use with several readily testable examples.
Freezing of geometric discords for two qutrits in environments
Authors: Xiao Wei , Zhen Mei-Yun , Hou Xi-Wen
Published: July 2022

Several measures of geometric discords have been recently proposed and mostly characterized in qubits. In this work, the dynamics of four measures of geometric discords is studied for two kinds of initial states in the two-qutrit model under environments. It is shown that four indicators can display freezing in Markovian regime and multiple freezing with multiple sudden changes in non-Markovian regime for suitable initial states and model parameters. Moreover, those measures evolve in a similar manner, but they differ from the decaying or increasing rate, the oscillatory amplitude and the time interval of freezing. However, they do not exhibit any freezing for the general Bell states. The dynamical hierarchy is discussed for those indicators. Those are helpful to understand the rich phenomena of discordant dynamics in open qutrits.
The Post-Buckling Analysis of Porous Sandwich Cylindrical Shells with Shape Memory Alloy Wires Reinforced Layers Under Mechanical Loads
Authors: Khosravi Farshid
Published: July 2022

The main purpose of this paper is to analyze the nonlinear post-buckling behavior of three-layer porous sandwich cylindrical shells with shape memory alloy (SMA) wires reinforced outer layers under the mechanical loads. Considering the large deformations, the governing differential equations were extracted and then, using the Ritz energy method and considering the Airy function, the analytical expression for the critical stress of the system was extracted. Three types of porosity distributions were considered in the shell core and the mechanical properties of SMA-reinforced layers were determined using the law of mixtures. After validating the results, the effect of various parameters such as porosity distribution, volume fraction of SMA wires and geometric characteristics on nonlinear buckling loads and post-buckling behavior of these structures has been investigated. According to the results, it can be seen that the difference in critical buckling stress for three different porosity distribution types is significant, which reveals the need to determine the optimal porosity distribution for composite shells reinforced with SMA wires. The results show that the SMA wires increase the equivalent stiffness of the structure and their presence has a significant effect on improving the critical axial stress of the shells. According to the results, for the use of 1% volume fraction of SMA wires, the axial stress of sandwich shells can be increased up to about 51%. Therefore, the use of SMA wires is a good method to increase the load-bearing capacity of this type of structures.
An Improved Element-Free Galerkin Method Based on the Dimension Splitting Moving Least-Squares Method for 2D Potential Problems in Irregular Domains
Authors: Sun Fengxin , Wang Jufeng , Wu Yong , Wei Qi
Published: July 2022

By introducing the dimension splitting (DS) method into the moving least-squares (MLS) approximation, a dimension splitting moving least-squares (DS-MLS) method is proposed in this paper. In the DS-MLS method, the operator splitting and independent variable splitting of the DS method are used to reduce the dimension, thereby reducing the computational complexity of the matrix. The shape function of the DS-MLS method has the advantages of simple derivation and high computational efficiency. Then, by coupling DS-MLS method and Galerkin weak form, and performing the coordinate transformation, an improved element-free Galerkin method (IEFGM) based on the DS-MLS method is proposed for two-dimensional (2D) potential problems on irregular domains. The effectiveness of the method in this paper is verified by some numerical examples. The numerical results show that, compared with the element-free Galerkin (EFG) method, the IEFGM based on the DS-MLS method in this paper consumes less CPU time and has higher computational accuracy for some 2D potential problems on irregular domains.
Modeling of the Initial Stage of Wave Generation by a Suddenly Rising or Falling Seabed
Authors: Chang Chih-Hua
Published: July 2022

In this study, a three-dimensional entirely nonlinear model was used for simulating the wave generation problem caused by seabed movement. This study focuses on the waveform of the initial stage of wave generation. The numerical model was verified by comparing the simulated results with existing experimental results. Satisfactory results of the waveforms and flow fields were obtained. The simulations of the free surface disturbances and flow field velocities caused by the sudden rising or falling of a circular cylinder with the dimensionless radius ([Formula: see text]) and height ([Formula: see text]) normalized by still-water depth are discussed. We considered the combinations of [Formula: see text]–10 and [Formula: see text]–0.3. For the moving cylinder with a moderate height (e.g. [Formula: see text] and [Formula: see text]) and [Formula: see text], it is found that the water-surface shape is closer to the shape of the terrain. The central water level ([Formula: see text]) varying with time is also focused herein. For the rising cylinder, when [Formula: see text], the maximum [Formula: see text] is always less than its corresponding [Formula: see text] for any [Formula: see text]. For the falling cylinder, if [Formula: see text] is larger than five times the still water depth, then the maximum [Formula: see text] will exceed its corresponding [Formula: see text]. This result provides a further understanding of the basic phenomenon of the initial waves caused by the movement of the seabed topography.
Estimation and Application of Strength and Stiffness Reduction Factors of Liquefiable Soil
Authors: Chou Jui-Ching , Chiang Ming-Yen , Tang Ciao-Rou
Published: July 2022

The reduction of soil strength and stiffness caused by soil liquefaction is an important issue in designing pile or shallow foundations on liquefiable soils. In practice, strength and stiffness reduction is considered via a reduction factor ([Formula: see text]) approach in seismic design. Different sets of values of [Formula: see text] are available according to the factor of safety against liquefaction ([Formula: see text]) of the liquefiable soil; these ([Formula: see text]) values are usually calculated using simplified liquefaction analysis procedures. Each set of [Formula: see text] is calibrated and constructed for specific simplified liquefaction analysis procedures or soil conditions. Thus, engineers have difficulty in selecting [Formula: see text] when using a simplified liquefaction analysis procedure without a corresponding set of [Formula: see text]. In this study, values of [Formula: see text] for simplified liquefaction analysis procedures commonly used in Taiwan are obtained using a single element test via FLAC program and UBCSAND model. In addition, a novel application of [Formula: see text] is introduced to improve the usability of the simplified numerical procedure used to predict the liquefaction-induced settlement of a shallow foundation. Simulation results show that the simplified numerical procedure with [Formula: see text] approach yields a convincing and conservative result.
Influences of Wall Configurations on Earthquake Behavior of Cantilever Retaining Walls Considering Soil-Structure Interaction Effects
Authors: Ozturk Kasif Furkan , Cakir Tufan , Araz Onur
Published: July 2022

Cantilever walls are frequently and necessarily built not only in earthquake prone regions but also on different foundation subsoils with various physical and mechanical characteristics. The response of these structures is a complicated soil-structure interaction (SSI) problem, in which the relative stiffness between the soil and structure is of critical importance. In addition to different soil conditions and earthquake motions, the wall configurations have an important role in the cantilever retaining wall design. Thus, the major objective of this work is to investigate the effects of various configurations on seismic response of the cantilever retaining walls considering SSI. Accordingly, the seismic response of the interaction systems is revealed using the 3D finite element models (FEM) in time domain, assuming linearly elastic behavior for the wall, and elastoplastic behavior for backfill and foundation soil. Viscous absorbent boundaries are employed to both simulate radiation scenario and avoid undesirable wave reflections generated by soil lateral boundaries. Backfill-wall interfaces are modeled using the unidirectional interface elements with nonlinear force-deflection abilities. The interaction systems are analyzed considering three different cantilever wall configurations (inverted T-type, L-type, and the wall with a base key), four different ground motion records, and four different subsoil systems. Nonlinear seismic analyses are carried out to visit how considering the variation of these parameters influences the wall behavior. The results from parametric studies show that the wall configuration, SSI effects and ground motions are remarkably influential on seismic responses of the cantilever walls such as the stresses and horizontal displacements.
Friction Tuned Mass Dampers in Seismic-Excited High-Rise Buildings with SSI Effects: A Reliability Assessment
Authors: Etedali Sadegh , Akbari Morteza , Seifi Mohammad
Published: July 2022

The probabilistic performance of the seismic-excited structures supplemented with passive control devices has recently received attention. Friction tuned mass damper (FTMD) devise as a novel passive control device is inspired by the idea of the combination of the friction mechanism with the traditional tuned mass damper (TMD) device. Although the application of the FTMD device has recently been considered for seismic control of structures, to the best of the authors’ knowledge, a probabilistic reliability evaluation of the high-rise building equipped with FTMD under near-field earthquakes considering soil-structure interaction (SSI) effects has not yet been addressed in the literature. In the presence of uncertainties considered for the structural model, FTMD model, foundation and soil model, and stochastic near-fault ground motion model, the reliability analyses are carried out on a benchmark 40-story building equipped with FTMD considering SSI effects to estimate the failure probabilities of both structures with and without FTMD. Three soil types, three earthquake magnitudes, three fault distances, and three seismic performance levels which include 162 reliability analyses are considered for the extension of the study. Considering different near-fault earthquake model parameters, a total average reduction of 51.13%, 49.42%, and 17.50% is given for the maximum inter-story drift ratio response of the structure equipped with FTMD than the uncontrolled ones. It is found that ignoring the uncertainties may result in an inaccurate estimation of the seismic responses of the tall buildings especially those built on soft soil near faults. The results show that the FTMD passive device is not able to satisfy the requirements of the seismic codes at the performance level of immediate occupancy, especially in high earthquake magnitudes and structures built near the fault. However, for the seismic performance levels of life safety and collapse prevention, the FTMD reduces failure probabilities of the structures for most conditions of the earthquake magnitudes and fault distances. The efficiency of the FTMD in the reduction of failure probability is often declined by increasing the softness of soils, especially for severe earthquakes closer to the fault.