Failure Envelopes of Single-Plate Rigid Helical Anchors for Floating Offshore Wind Turbine

Helical anchor is a kind of novel foundation for floating offshore wind turbines,which should be subjected to combined tensile loading caused by wind,wave and current.However,the research about the capacity of helical anchor was mainly examined under uniaxial loading and scarcely explored under combined loading.In this study,three-dimensional finite element limit analysis is adopted to assess the bearing capacities of single-plate rigid helical anchors with different ratios of helix to shaft diameter,D_(H)/D_(S) and embedment ratios L/D_(S).Result shows that the vertical,horizontal and moment bearing capacities increase with increasing D_(H)/D_(S) and L/D_(S).The normalized V-H failure envelopes expands with increasing L/D_(S),while the normalized V-M failure envelopes tend to contract with the increase of D_(H)/D_(S).With increasing D_(H)/D_(S) or decreasing L/D_(S),the normalized H-M failure envelopes expand when the horizontal and moment loading act in the same direction and contract when they act in the opposite direction.The effect of D_(H)/D_(S) and L/D_(S) on the shape of H-M failure envelope become insignificant when L/D_(S)≥4.A series of failure mechanisms under different loading conditions were observed and can be used to explain the trend.Besides,a series of approximate expressions were proposed to fit the uniaxial bearing capacities and the failure envelopes.

Thermal performance of integration of solar collectors and building envelopes

The integration of building with solar collector was studied. The theoretical model of integration of building envelopes and flat plate solar collectors was set up and the thermal performance of integration was studied in winter and summer,and compared to envelopes without solar collectors. The results show that the solar collection efficiency is raised in the integration of building envelopes and solar collectors with the air layer doors closed. This is true whether in winter or summer. The increment is higher as the inlet water temperature increases or the ambient temperature is low. In winter,the heat loss is significantly reduced through integration of the building envelopes and solar collectors with the closed air layer doors. The integration with the open air layer door is worse than that without collectors. In summer,the heat gains of the integration of envelopes and solar collectors are more obviously reduced than envelopes without collectors,the integration with the open air layer door is a little better than the closed one,but the difference is very small.

Dynamism and Soft Robotics in the Intelligence of the New Design of Lightweight Envelopes

The innovation of building envelopes is densely characterized, in the new design process, by new products of the building industry and intelligent robotic systems, making them efficient and dynamic in an eco-efficient environmental context and spatial flexibility. The goal is that of energy efficiency and environmental sustainability that invest above all the building production sector, pushing towards a circular economy with the use of clean energy resources and new artificial intelligence systems. The intelligence is highlighted through the optimization of the performance of new lightweight envelopes, in the technological design and the new building process, through Lean planning and Lean construction, Mass customization, with application of criteria, methods and tools. So there are innovative technological solutions, for environmental comfort and energy saving, and typological solutions with high performance level, with the use of innovative, adaptive, advanced, light materials with nanoproducts, intelligent IT systems, etc. We highlight the effectiveness of design with natural passive use of renewable energy and energy efficiency of the envelope as “skin” and relative increase in performance levels, in the interaction with the internal environment and natural dynamic flows and in the conversion of thermal and electrical energy. The methodologies are aimed at the application of digital technologies and soft robotic systems for the management and quality of services with technological and constructive solutions for dynamic interactive envelope and intelligent systems of double or triple skin, curtain walls, etc. The challenge is new design models of dynamic enclosures, on criteria and methods that guide the new rules on energy efficiency in buildings, for environmental sustainability and housing quality with the integration of soft robots.

Simple Proofs of Upper and Lower Envelopes of Van Der Pauw’s Equation for Hall-Plates with an Insulated Hole and Four Peripheral Point-Contacts

For plane singly-connected domains with insulating boundary and four point-sized contacts, C0 …C3, van der Pauw derived a famous equation relating the two trans-resistances R01,23, R12,30 with the sheet resistance without any other parameters. If the domain has one hole van der Pauw’s equation becomes an inequality with upper and lower bounds, the envelopes. This was conjectured by Szymański et al. in 2013, and only recently it was proven by Miyoshi et al. with elaborate mathematical tools. The present article gives new proofs closer to physical intuition and partly with simpler mathematics. It relies heavily on conformal transformation and it expresses for the first time the trans-resistances and the lower envelope in terms of Jacobi functions, elliptic integrals, and the modular lambda elliptic function. New simple formulae for the asymptotic limit of a very large hole are also given.

Construction of Bode Envelopes Using REP Based Range Finding Algorithms

The frequency domain analysis of systems is an important topic in control theory. Powerful graphical tools exist in classic control, such as the Nyquist plot, Bode plots, and Nichols chart. These methods have been widely used to evaluate the frequency domain behavior of system. A literature survey shows that various approaches are available for the computation of the frequency response of control systems under different types of parametric dependencies, such as affine, multi-linear, polynomial, etc. However, there is a lack of tools in the literature to construct the Bode envelopes for the general nonlinear type of parametric dependencies. In this paper, we address the problem of computation of the envelope of Bode frequency response of a non-rational transfer function with nonlinear parametric uncertainties varying over a box. We propose two techniques to compute the Bode envelopes：first, based on the natural interval extensions （NIE） combined with uniform subdivision and second, based on the existing Taylor model combined with subdivision strategy. We also propose the algorithms to further speed up both methods through extrapolation techniques.

PARAMETRIC WAVEFORMS AND SPECTRA OF THE PRIMARY PULSES WITH TWO KINDS OF ENVELOPES

The integral of the pulse self-demodulation in acoustic parametric array can be calculated in light of the Fourier convolution theorem.Instead of a rectangular pulse with two discontinuous edges,two kinds of primary envelopes are used,the waveforms and their spectra are investigated.An optimal ratio of the primary duration has been found theoretically.Experimental results support this theory.

Risk profiles and outcomes of patients receiving antibacterial cardiovascular implantable electronic device envelopes:A retrospective analysis

BACKGROUND Cardiovascular implantable electronic devices(CIEDs)are implanted in an increasing number of patients each year,which has led to an increase in the risk of CIED infection.Antibacterial CIED envelopes locally deliver antibiotics to the implant site over a short-term period and have been shown to reduce the risk of implant site infection.These envelopes are derived from either biologic or nonbiologic materials.There is a paucity of data examining patient risk profiles and outcomes from using these envelope materials in the clinical setting and comparing these results to patients receiving no envelope with their CIED implantation.AIM To evaluate risk profiles and outcomes of patients who underwent CIED procedures with an antibacterial envelope or no envelope.METHODS After obtaining Internal Review Board approval,the records of consecutive patients who underwent a CIED implantation procedure by a single physician between March 2017 and December 2019 were retrospectively collected from our hospital.A total of 248 patients within this period were identified and reviewed through 12 mo of follow up.The CIED procedures used either no envelope(n=57),a biologic envelope(CanGaroo®,Aziyo Biologics)that was pre-hydrated by the physician with vancomycin and gentamicin(n=89),or a non-biologic envelope(Tyrx^(TM),Medtronic)that was coated with a resorbable polymer containing the drug substances rifampin and minocycline by the manufacturer(n=102).Patient selection for receiving either no envelope or an envelope(and which envelope to use)was determined by the treating physician.Statistical analyses were performed between the 3 groups(CanGaroo,Tyrx,and no envelope),and also between the No Envelope and Any Envelope groups by an independent,experienced biostatistician.RESULTS On average,patients who received any envelope(biologic or non-biologic)were younger(70.7±14.0 vs 74.9±10.6,P=0.017),had a greater number of infection risk factors(81.2%vs 49.1%,P<0.001),received more high-powered devices(37.2%vs 5.8%,P=0.004),and were undergoing more reoperative procedures(47.1%vs 0.0%,P<0.001)than patients who received no envelope.Between the two envelopes,biologic envelopes tended to be used more often in higher risk patients(84.3%vs 78.4%)and reoperative procedures(62.9%vs 33.3%)than non-biologic envelopes.The rate of CIED implant site pocket infection was low(any envelope 0.5%vs no envelope 0.0%)and was statistically equivalent between the two envelope groups.Other reported adverse events(lead dislodgement,lead or pocket revision,device migration or erosion,twiddler’s syndrome,and erythema/fever)were low and statistically equivalent between groups(biologic 2.2%,non-biologic 3.9%,no envelope 1.8%).CONCLUSION CIED infection rates for biologic and non-biologic antibacterial envelopes are similar.Antibacterial envelopes may benefit patients who are higher risk for infection,however additional studies are warranted to confirm this.

Calibration of Four Nonlinear Failure Envelopes from Triaxial Test Data and Influence of Nonlinearity on Geotechnical Computations

It is now recognized that many geomaterials have nonlinear failure envelopes. This non-linearity is most marked at lower stress levels, the failure envelope being of quasi-parabolic shape. It is not easy to calibrate these nonlinear failure envelopes from triaxial test data. Currently only the power-type failure envelope has been studied with an established formal procedure for its determination from triaxial test data. In this paper, a simplified procedure is evolved for the development of four different types of nonlinear envelopes. These are of invaluable assistance in the evaluation of true factors of safety in problems of slope stability and correct computation of lateral earth pressure and bearing capacity. The use of the Mohr-Coulomb failure envelopes leads to an overestimation of the factors of safety and other geotechnical quantities.

Three-Dimensional Sound Source Location Algorithm for Subsea Leakage Using Hydrophone

Leakages from subsea oil and gas equipment cause substantial economic losses and damage to marine ecosystem,so it is essential to locate the source of the leak.However,due to the complexity and variability of the marine environment,the signals collected by hydrophone contain a variety of noises,which makes it challenging to extract useful signals for localization.To solve this problem,a hydrophone denoising algorithm is proposed based on variational modal decomposition(VMD)with grey wolf optimization.First,the average envelope entropy is used as the fitness function of the grey wolf optimizer to find the optimal solution for the parameters K andα.Afterward,the VMD algorithm decomposes the original signal parameters to obtain the intrinsic mode functions(IMFs).Subsequently,the number of interrelationships between each IMF and the original signal was calculated,the threshold value was set,and the noise signal was removed to calculate the time difference using the valid signal obtained by reconstruction.Finally,the arrival time difference is used to locate the origin of the leak.The localization accuracy of the method in finding leaks is investigated experimentally by constructing a simulated leak test rig,and the effectiveness and feasibility of the method are verified.

A Proposal for the Automatic Computation of Envelopes of Families of Plane Curves

The idea of envelope of a family of plane curves is an elementary notion in differential geometry. As such, its implementation in dynamic geometry environments is quite universal(Cabri,The Geometer's Sketchpad, Cinderella, Geo Gebra,...). Nevertheless, most of these programs return,when computing certain envelopes, both some spurious solutions and the curves that truly ?t in the intuitive de?nition of envelope. The precise distinction between spurious and genuine parts has not been made before: This paper proposes such distinction in an algorithmic way, ready for its implementation in interactive geometry systems, allowing a ?ner classi?cation of the different parts resulting from the current, advanced approach to envelope computation and, thus, yielding a more precise output, free from extraneous components.

Trial application of the envelope method to the potential ambiguity problem

The optical potential ambiguity is a long-standing problem in the analysis of elastic scattering data.For a specific collid-ing system,ambiguous potential families can lead to different behaviors in the nearside and farside scattering components.By contrast,the envelope method can decompose the experimental data into two components with negative and positive deflection angles,respectively.Hence,a question arises as to whether the comparison between the calculated nearside(or farside)component and the derived positive-deflection-angle(or negative-deflection-angle)component can help analyze the potential ambiguity problem.In this study,we conducted a trial application of the envelope method to the potential ambiguity problem.The envelope method was improved by including uncertainties in the experimental data.The colliding systems of 16O+28Si at 215.2 MeV and 12C+12C at 1016 MeV were considered in the analyses.For each colliding system,the angular distribution experimental data were described nearly equally well by two potential sets,one of which is“surface transpar-ent”and the other is refractive.The calculated angular distributions were decomposed into nearside and farside scattering components.Using the improved envelope method,the experimental data were decomposed into the positive-deflection-angle and negative-deflection-angle components,which were then compared with the calculated nearside and farside components.The capability of the envelope method to analyze the potential ambiguities was also discussed.

An envelope-based machine learning workflow for locating earthquakes in the southern Sichuan Basin

The development of machine learning technology enables more robust real-time earthquake monitoring through automated implementations. However, the application of machine learning to earthquake location problems faces challenges in regions with limited available training data. To address the issues of sparse event distribution and inaccurate ground truth in historical seismic datasets, we expand the training dataset by using a large number of synthetic envelopes that closely resemble real data and build an earthquake location model named ENVloc. We propose an envelope-based machine learning workflow for simultaneously determining earthquake location and origin time. The method eliminates the need for phase picking and avoids the accumulation of location errors resulting from inaccurate picking results. In practical application, ENVloc is applied to several data intercepted at different starting points. We take the starting point of the time window corresponding to the highest prediction probability value as the origin time and save the predicted result as the earthquake location. We apply ENVloc to observed data acquired in the southern Sichuan Basin, China, between September 2018 and March 2019. The results show that the average difference with the catalog in latitude, longitude, depth, and origin time is 0.02°,0.02°, 2 km, and 1.25 s, respectively. These suggest that our envelope-based method provides an efficient and robust way to locate earthquakes without phase picking, and can be used in earthquake monitoring in near-real time.

Optimal regularity of plurisubharmonic envelopes on compact Hermitian manifolds

In this paper, we prove the C^(1,1)-regularity of the plurisubharmonic envelope of a C^(1,1) function on a compact Hermitian manifold. We also present the examples to show this regularity is sharp.

Evaluation of Energy Efficiency and Analysis of Influencing Factors of Company CW’s Manufacturing Workshops

In this work,the Slacks-Based Measure(SBM)model within Data Envelopment Analysis was employed to establish a set of indicators for evaluating the energy efficiency of manufacturing workshops.The energy efficiency of 12 Company CW’s manufacturing workshops from 2016 to 2022 was assessed.The findings indicated that aside from a few workshops operating at the production frontier,the rest exhibit significant fluctuations in energy efficiency and generally low energy efficiency.Subsequently,a combined GRA-Tobit analysis model was introduced to identify factors influencing the energy efficiency of Company CW’s manufacturing workshops.Regression analysis revealed that technological investments,employee quality,workshop production scale,investment in clean energy,and the level of pollution control all significantly impact the energy efficiency of Company CW’s manufacturing workshops.By evaluating the energy efficiency of Company CW’s manufacturing workshops and studying their influencing factors,this research aids company managers in understanding the energy efficiency of the manufacturing process.It optimizes the combination of various production elements,thereby offering effective guidance for improving the energy efficiency issues of the company’s manufacturing workshops,which can contribute to enhancing the corporation’s overall energy efficiency.

Injective envelopes,cogenerators and direct products in the Doi-Hopf module category

It is proved that there exist injective envelopes, cogenerators and direct products in the Doi-Hopf module category.

Restricted Envelopes of Lie Superalgebrast

Certain important results concerning p-envelopes of modular Lie algebras are generalized to the super-case. In particular, any p-envelope of the Lie algebra of a Lie superalgebra can be naturally extended to a restricted envelope of the Lie superalgebra. As an application, a theorem on the representations of Lie superalgebras is given, which is a super-version of Iwasawa＇s theorem in Lie algebra case. As an example, the minimal restricted envelopes are computed for three series of modular Lie superalgebras of Cartan type.

Some Specific Unboundedness Property in Smoothness Morrey Spaces. The Non-existence of Growth Envelopes in the Subcritical Case

Abstract We study smoothness spaces of Morrey type on Rn and characterise in detail those situa s,r n s n tions when such spaces of type Ap,q^s,r（Rn ） or A u^sp,q（R ） are not embedded into L∞（R^n）. We can show that in the so-called sub-critical, proper Morrey case their growth envelope function is always infinite which is a much stronger assertion. The same applies for the Morrey spaces Mu,p（Rn） with p 〈 u. This is the first result in this direction and essentially contributes to a better understanding of the structure of the above spaces.

Relatively Flat Envelopes

The aim of this paper is to investigate relatively flat envelopes. A necessary and sufficient condition is given for a relatively-finitely presented module to have a (mono-morphic or epic) relatively flat envelope. Then those rings are characterized whose every relatively-finitely presented module has a relatively flat envelope which coincides with its in-jective envelope. Some known results are obtained as corollaries.

Envelopes of Two Families of Chords of an Ellipse

In this paper, we investigate the envelope of two special families of chords of an ellipse and prove that the envelopes are also ellipses. The obtained results are important for computerized design of the generation of envelope curves and examples are illustrated graphically with Matlab.

Envelopes of Commutative Rings

Given a significative class F of commutative rings, we study the precise conditions under which a commutative ring R has an S-envelope. A full answer is obtained when F is the class of fields, semisimple commutative rings or integral domains. When .F is the class of Noetherian rings, we give a full answer when the Krull dimension of R is zero and when the envelope is required to be epimorphic. The general problem is reduced to identifying the class of non-Noetherian rings having a monomorphic Noetherian envelope, which we conjecture is the empty class.