Correlation and spectral theory for periodically correlated random fields indexed on Z2

We show that a field X(m, n) is strongly periodically correlated with period (M, N) if and only if there exist commuting unitary operators, U1and U2that shift the field unitarily by M and N along the respective coordinates. This is equivalent to a field whose shifts on a subgroup are unitary. We also define weakly PC fields in terms of other subgroups of the index set over which the field shifts unitarily. We show that every strongly PC field can be represented as X(m, n) = U1mU2n(m, n) where U1and U2are unitary and P(m, n) is a doubly periodic vector-valued sequence. This leads to the Gladyshev representations of the field and to strong harmonizability. The 2- and 4-fold Wold decompositions are expressed for weakly commuting strongly PC fields. When the field is strongly commuting, a one-point innovation can be defined. For this case, we give necessary and sufficient conditions for a strongly commuting field to be PC and strongly regular, although possibly of deficient rank, in terms of periodicity and summability of the southwest moving average coefficients

Improving hydro-formability of stainless steel tubes by tube channel pressing

© Published under licence by IOP Publishing Ltd. Tube channel pressing (TCP), which is one of the severe plastic deformation (SPD) technologies to refine grain size into submicron size for tubular materials, have been applied to ferritic stainless steel tubes for one pass, in order to alleviate ridging and enhance the hydro-formability. It was found that grain-scale shear bands were introduced by one-pass TCP, and texture and microstructure was successfully modified by promoting recrystallization of deformation microstructure, which is otherwise hard-to-recrystallize, in the post-TCP annealing. Elongation to failure, strain-hardening exponent (n-value) and Lankford values of both longitudinal and circumferential directions increased in comparison to with the tube fabricated by conventional process.Japan Science and Technology Agency (JST) matching planner program

The relationship between a plant-based diet and mental health: Evidence from a cross-sectional multicentric community trial (LIPOKAP study)

BACKGROUND: Dietary patterns emphasizing plant foods might be neuroprotective and exert health benefits on mental health. However, there is a paucity of evidence on the association between a plant-based dietary index and mental health measures. OBJECTIVE: This study sought to examine the association between plant-based dietary indices, depression and anxiety in a large multicentric sample of Iranian adults. METHODS: This cross-sectional study was performed in a sample of 2,033 participants. A validated food frequency questionnaire was used to evaluate dietary intakes of participants. Three versions of PDI including an overall PDI, a healthy PDI (hPDI), and an unhealthy PDI (uPDI) were created. The presence of anxiety and depression was examined via a validated Iranian version of the Hospital Anxiety and Depression Scale (HADS). RESULTS: PDI and hPDI were not associated to depression and anxiety after adjustment for potential covariates (age, sex, energy, marital status, physical activity level and smoking). However, in the crude model, the highest consumption of uPDI approximately doubled the risk of depression (OR= 2.07, 95% CI: 1.49, 2.87; P<0.0001) and increased the risk of anxiety by almost 50% (OR= 1.56, 95% CI: 1.14, 2.14; P= 0.001). Adjustment for potential confounders just slightly changed the associations (OR for depression in the fourth quartile= 1.96; 95% CI: 1.34, 2.85, and OR for anxiety in the fourth quartile= 1.53; 95% CI: 1.07, 2.19). CONCLUSIONS: An unhealthy plant-based dietary index is associated with a higher risk of depression and anxiety, while plant-based dietary index and healthy plant-based dietary index were not associated to depression and anxiety

Correlation and Spectral Theory for Periodically Correlated Random Fields Indexed on Z&amp;sup2;

This paper is concerned with second order random fields, indexed on Z 2 , whose correlation functions are invariant under shifts of certain lengths in some of the variables. Primarily we study the strongly PC (periodically correlated) fields in which the field X(m;n) is PC in m with period M for every n and PC in n with period N for every m. We also define weakly PC fields in terms of subgroups of the index set over which the field evolves unitarily. We first extend Gladyshev&apos;s results for PC sequences by giving necessary and sufficient conditions on a collection of Fourier coefficient functions to belong to the correlation of some strongly periodically correlated field. It is also shown that two-dimensional strongly PC fields are strongly harmonizable. Next we show the relationship of unitary operators to strongly PC fields. In essence, a field X is periodically correlated with period (M;N) if and only if there exists a pair of commuting unitary operators, U 1 and U 2 operating in ..

The factors relevant to the onset of vascular complications after coronary intervention in Shahid Rajaei Cardiovascular Center in Tehran, Iran

&quot;nBackground: Vascular complications, as the most common complications of diagnostic catheterization and percutaneous coronary intervention (PCI), are important factors in the morbidity of patients undergoing such procedures; thus, this study was done to evaluate the prevalence of these complications and their related factors.&quot;n &quot;nMethods: This is a descriptive study composed of 2097 consecutive patients who underwent percutaneous coronary intervention in Shahid Rajaei Cardiovascular Center in Tehran, Iran from January 2008 to January 2009. Occurrence of vascular complications in course of hospitalization and the related factors leading to the complications were investigated.&quot;n &quot;nResults: Out of 2097 patients, 1544 (73.6%) were male and 553 (26.4%) were female, and the mean age of the participants was 57&amp;plusmn;10 years. Vascular complications from the time of PCI to the time discharge were observed in 19 (0.9%) patients. The other complications included: hematoma in 10 cases (52.6%), pseudoaneurysm in five cases (26.3%), retroperitoneal hemorrhage and arteriovenous fistula in 2 (10.5%) patients each. The complications were significantly more common in female patients (P=0.003), in patients with a history of hypertension (P=0.02), people of shorter stature (P=0.004), and being on gp IIIa/IIb inhibitors (P=0.003).&quot;n &quot;nConclusion: The rate of vascular complications post-percutaneous coronary interventions is low and it is considered to be a good treatment option for patients with coronary stenosis; provided that sufficient compression is applied on the vascular access point in the right time after removal of the arterial sheath. PCI is of fewer vascular complications, especially in female patients, history of hypertension, and higher anticoagulant concentrations

Correlation and spectral theory for periodically correlated random fields indexed on Z2

We show that a field X(m,n) is strongly periodically correlated with period (M,N) if and only if there exist commuting unitary operators, U1 and U2 that shift the field unitarily by M and N along the respective coordinates. This is equivalent to a field whose shifts on a subgroup are unitary. We also define weakly PC fields in terms of other subgroups of the index set over which the field shifts unitarily. We show that every strongly PC field can be represented as where and are unitary and P(m,n) is a doubly periodic vector-valued sequence. This leads to the Gladyshev representations of the field and to strong harmonizability. The 2- and 4-fold Wold decompositions are expressed for weakly commuting strongly PC fields. When the field is strongly commuting, a one-point innovation can be defined. For this case, we give necessary and sufficient conditions for a strongly commuting field to be PC and strongly regular, although possibly of deficient rank, in terms of periodicity and summability of the southwest moving average coefficients.Random fields Periodically correlated processes Harmonizable processes Spectral theory Wold decomposition Prediction

An auction and witness enhanced trustworthy SLA model for decentralized cloud marketplaces

Cloud computing has become one of the most important technolo-gies that have changed the traditional application developmentand operation (DevOps) lifecycle. However, current cloud softwareDevOps often faces the following key challenges: 1) selecting thebest fitting service providers, customizing services and planningcapacities for large-scale distributed applications; 2) guarantee-ing high-quality and trustworthy service level agreements (SLAs)among multiple service providers; 3) enhancing the interoperabilityof cloud services across providers; 4) designing incentive modeleffectively among players. In this study, a framework called AWE-SOME is proposed to build a decentralized cloud marketplace andto address the above challenges. The proposed framework containsfour subsystems including a customizable auction model, an incen-tive witness mechanism, and a social behavior-based simulator asone automated framework. We also provide a proof of concept todemonstrate that the AWESOME framework is feasible