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We focus on mean-variance hedging problem for models whose asset price follows an exponential additive process. Some representations of mean-variance hedging strategies for jump-type models have al...

In the present work, the structure and properties of products from heat-resistant nickel-based superalloy ZhS6U formed by wire-feed electron beam additive technology were investigated. Products were obtained under different parameters of electron beam additive process (accelerating voltage, beam current and movement speed of working table were varied). It was shown that a high speed of displacement leads to the formation of defects in the form of cracks and delamination of the obtained product from the substrate, which also leads to the appearance of cracks. It has been established that the greatest energy input leads to evaporation of aluminum (the main hardening γ’ phase). The phase composition of the additive product did not differ from the original material.

Digital fabrication represents innovative, computer-controlled processes and technologies with the potential to expand the boundaries of conventional construction. Their use in construction is currently restricted to complex and iconic structures, but the growth potential is large. This paper aims to investigate the environmental opportunities of digital fabrication methods, particularly when applied to complex concrete geometries. A case study of a novel robotic additive process that is applied to a wall structure is evaluated with the Life Cycle Assessment (LCA) method. The results of the assessment demonstrate that digital fabrication provides environmental benefits when applied to complex structures. The results also confirm that additional complexity is achieved through digital fabrication without additional environmental costs. This study provides a quantitative argument to position digital fabrication at the beginning of a new era, which is often called the Digital Age in many other disciplines.

The Common Agricultural Policy (CAP) has undergone different reforms often presented as a historical evolutionary process in which old policy instruments are replaced by new measures. In this paper we explore the current nature and developments of the CAP by interviewing experts closely involved in the reforms either as commentators or lobbyists. The results show a policy historically built by an additive process of layering specific instruments on top of the others. This multilayered nature implies structural challenges. Interviews reveal a strong dispute between powerful lobby groups and their paradigms for more space within the CAP. Current developments include the effort for incorporating environmental issues within the CAP promoted by environmentalists and the proposal for sustainable intensification promoted by farmers.

The main motivations for this study arise from the need for an assessment of the fatigue performance of DMLS produced Maraging Steel MS1, when it is used in the “as fabricated” state. The literature indicates a lack of knowledge from this point of view, moreover the great potentials of the additive process may be more and more incremented, if an easier and cheaper procedure could be used after the building stage. The topic has been tackled experimentally, investigating the impact of heat treatment, machining and micro-shot-peening on the fatigue strength with respect to the “as built” state. The results indicate that heat treatment significantly enhances the fatigue response, probably due to the relaxation of the post-process tensile residual stresses. Machining can also be effective, but it must be followed (not preceded) by micro-shot-peening, to benefit from the compressive residual stress state generated by the latter.

A relatively simple mathematical model is proposed and developed that allows using additive process mechanics approaches to trace the evolution of technological stress fields in cylindrical composites during their manufacture by slow multi-layer winding of fibre-reinforced material with an arbitrary variation in the pre-tension force and fibre packing density. The constructed closed analytical dependences make it possible to state problems on controlling the distributions of these stresses.

Technological processes of layer-by-layer manufacturing of cylindrical products by the method of power winding of a thin tape on a sufficiently rigid circular base are considered. A characteristic factor for the processes under consideration is the creation of initial stresses in the elementary layers of additional material, which are sequentially included in the composition of the being formed product. It is assumed that the applied winding technology allows us to arbitrarily influence these stresses. This makes it possible to control the technological stresses developing in the resulting product. This paper is devoted to the formulation and solution of one of the problems of such control using current approaches of additive process mechanics. The simulation is performed in a quasi-static approximation within the limits of small elastic strains. A non-classical mechanical model of the process under study is proposed, and a mathematical formulation of the corresponding initial boundary value problem and its closed analytical solution are given. Based on the constructed solution, the regularities of the influence of the initial stress state of the attached material on the nature of the development of the contact pressure on the used base from the side of the material layer formed on it are studied. The problem of providing the required law of change in the value of this pressure in the process under consideration by setting the appropriate program for varying the initial stresses is formulated and solved. Corollaries of an applied nature are made.

Lately, Semi Additive process has been considered to dry processing for the downsizing of the emiconductor packages. WET process is a process depending on the chemical reaction of the chemical solution. There are many problems with the formation of the minute redistribution layer. We repeated the study of the Photodesmear technology as a new technology of the dry process, reported result in IMAPS in 2013 and 2015. We completed a panel level experiment tool equipped with a high power irradiation light source. We reported findings of the coherency improvement by integrated dry process which fused in a Photodesmear technology and a dry seed technology. We confirmed the following effects in integrated dry process. Desmear of micro via was difficult at a panel level. We were able to keep flatness characteristics of the resin before the plating low. We were able to confirm strong coherence of the via filled plating. VUV light irradiation is effective for the residue that is left when removing the protective film before the pre-dry seed layer process. Integrated dry process is a key technology to establish the next generation semi additive process.

We study a bistable gradient system perturbed by a stable-like additive process with a periodically varying stability index. Among a continuum of intrinsic time scales determined by the values of the stability index we single out the characteristic time scale on which the system exhibits the metastable behaviour, namely it behaves like a time discrete two-state Markov chain.

Current methods to spatiotemporally modify stimuli response in hydrogels are typically subtractive and lead to a decrease in response. To increase the breadth of hydrogel applications and biomedical systems, new formulations are needed that can introduce and increase stimuli response spatiotemporally in hydrogels. In this work, the light-induced thiol–norbornene click chemistry reaction was used to modify the stimuli response of robust hyaluronic acid hydrogels through an additive process in spatiotemporal fashion, overcoming this limitation. These stimuli-responsive hydrogels were made from norbornene-functionalized hyaluronic acid (NorHA) cross-linked with thermoresponsive dithiol-terminated poly(N-isopropylacrylamide) (DTPN). Variation of the cross-linker molecular weight and gelation conditions led to a range of compression modulus (5 to 54 kPa) and mass loss (9 to 33%) upon heating to 37 °C while retaining a majority of NorHA in the hydrogel. The thermoresponse of these hydrogels could be controlled ...

Both the spanwise and the vertical velocity components in high-Reynolds-number wall-bounded flows may be modeled via a random additive process. Evidence shows that a hierarchical, treelike structure exists for the spanwise velocity component.

This paper presents the investigations regarding the reactions of nano Ag catalysts and Pd catalysts on Cu foils. According to the survey, the nano Ag catalysts can be removed immediately and detached from the Cu foils in seed layer etching steps. But the Pd catalysts will deposit on the Cu foils again while etching because of the substitution from Cu to Pd; consequently the Pd catalyst steps will cause the deposition outside fine patterns in final treatments even in Modified Semi Additive Process (MSAP). With the electroless copper plating process using the nano Ag catalysts, it becomes possible to conduct the ultra-fine patterning of Line/Space (L/S) = 5 μm/5 μm.

The additive process of forming a semicircular arched structure by means of layer-by-layer addition of material to its inner surface is simulated. The impact of this process running mode on the development of the technological stresses fields in the structure being formed under the action of gravity under properties of the material creep and aging is examined. In the framework of the linear mechanics of accreted solids a mathematical model of the process under study is offered and numerical experiments are conducted. It is shown that the stress-strain state of the additively formed heavy objects decisively depends on their formation mode. Various practically important trends and features of this dependence are studied.

For real-valued additive process ( X t ) t ≥ 0 a recursive equation is derived for the entire positive moments of functionals I s , t = ∫ s t exp ( − X u ) d u , 0 ≤ s t ≤ ∞ , in case the Laplace exponent of X t exists for positive values of the parameter. From the equation emerges an easy-to-apply sufficient condition for the finiteness of the moments. As an application we study first hit processes of diffusions.

Wireframe models are becoming a popular option in 3D printing. Generating sparse wireframe models using classic mesh simplification methods leads to models that require a lot of support structures in the layer-upon-layer additive process. In this paper we present a mesh simplification method that takes into account the overhang angle. Specifically, we propose a metric for self-supportability. By combining this novel metric together with the classic error metrics for mesh simplification, our method generates sparse wireframe models that need much less supports. Moreover, the operations of vertex position optimization and edge flipping are used to further increase self-supportability of the wireframe models. We demonstrate the effectiveness of the proposed method on a number of 3D models.

This paper reviews the state-of-the-art of an additive process planning methods amd models. Paper deals with the literature review of the planning process of additive manufacturing. The study also demonstrate multi-criteria planning model of engines parts additive manufacturing using multi-attributes decision-making problems approach.

This article will focus on recent reports that have applied three-dimensional (3D) printing for designing millimeter to micrometer architecture for robotic motility. The utilization of 3D printing has rapidly grown in applications for medical prosthetics and scaffolds for organs and tissue, but more recently has been implemented for designing mobile robotics. With an increase in the demand for devices to perform in fragile and confined biological environments, it is crucial to develop new miniaturized, biocompatible 3D systems. Fabrication of materials at different scales with different properties makes 3D printing an ideal system for creating frameworks for small-scale robotics. 3D printing has been applied for the design of externally powered, artificial microswimmers and studying their locomotive capabilities in different fluids. Printed materials have also been incorporated with motile cells for bio-hybrid robots capable of functioning by cell contraction and swimming. These 3D devices offer new methods of robotic motility for biomedical applications requiring miniature structures. Traditional 3D printing methods, where a structure is fabricated in an additive process from a digital design, and non-traditional 3D printing methods, such as lithography and molding, will be discussed.

For Gaussian random fields defined as additive processes based on Slepian processes, we study their Karhunen–Loeve expansions and obtain the Pythagorean type distribution identities. As applications, the corresponding small deviation estimates are given.

Pareto distributions are most popular for modeling heavy tailed data. Here, we obtain weak limits of a sequence of extremal and a sequence of additive processes constructed by a series of Bernoulli point processes with bivariate Pareto space components. For the limiting processes we derive the one dimensional distributions in explicit forms. Some of the main properties of these distributions are also proved.

Recently changes in the semiconductor industry continue toward higher functionality that leads to higher input/output (I/O) counts, pushing packaging towards higher density architectures. With increasing these market demands of electric products, printed circuit board (PCB) are pushed to accommodate these requirements also. In other words, PCB industry is experiencing tremendous pressure to enhance the wiring density and reduce that feature size of PCBs, while retaining low cost. To keep up these trends, we developed substrate technology with ultra fine line/space and high aspect ratio using sputter, photolithography and semi additive process (SAP). Photolithography is the technology of reproducing images or patterns by using UV light. The designed patterns for constructing circuits are transferred onto a photosensitive thin or thick film by photolithographic method. This technology dominates the process capability of producing fine line structure. Wet etch is currently the most popular subtractive method used in PCB industry. It is known as low resolution technology due to the nature of isotropic etches or undercut. To minimize undercut, we introduced sputtering system to SAP method for seed layer deposition. SAP method is used for build up substrate manufacturing and uses electrolytic copper plating to fill in the patterned photo resist. In this study, we have successfully formed copper lines of sub 5um which have bellow 0.5um undercut by using SAP method and photolithography.

The primary objective of this project was to leverage the Big Area Additive Manufacturing (BAAM) process and materials into a long term, quick change tooling concept to drastically reduce product lead and development timelines and costs. Current refrigeration foam molds are complicated to manufacture involving casting several aluminum parts in an approximate shape, machining components of the molds and post fitting and shimming of the parts in an articulated fixture. The total process timeline can take over 6 months. The foaming process is slower than required for production, therefore multiple fixtures, 10 to 27, are required per refrigerator model. Molds are particular to a specific product configuration making mixed model assembly challenging for sequencing, mold changes or auto changeover features. The initial goal was to create a tool leveraging the ORNL materials and additive process to build a tool in 4 to 6 weeks or less. A secondary goal was to create common fixture cores and provide lightweight fixture sections that could be revised in a very short time to increase equipment flexibility reduce lead times, lower the barriers to first production trials, and reduce tooling costs.

Ink-jet 3D printing is an additive manufacturing process where-in parts are built by jetting material from nozzles layer by layer, with curing between successive layers of deposition. Typically, this additive process is operated in an open-loop manner, i.e., the number of layers and droplet patterns for each layer are determined in advance and are not modified based on measurements of current height profile during the printing process. As a result, the uncertainties in droplet sizes, heights and locations during printing can result in undesired part geometry, such as edge shrinking, unreliable dimensions and uneven surfaces. Naturally, incorporating feedback measurements into the control algorithm will improve performance if suitable models and cost functions are constructed. In this paper, we first propose a control-oriented layer to layer height evolution model for two-material Ink-jet 3D printing. Based on this model, a predictive control algorithm that uses measurements of the current height profile to generate control inputs for successive layers is designed. The effectiveness of the proposed algorithm is demonstrated by simulation studies.

We characterize a comprehensive family of $d$-variate exogenous shock models. Analytically, we consider a family of multivariate distribution functions that arises from ordering, idiosyncratically distorting, and finally multiplying the arguments. Necessary and sufficient conditions on the involved distortions to yield a multivariate distribution function are given. Probabilistically, the attainable set of distribution functions corresponds to a large class of exchangeable exogenous shock models. Besides, the vector of exceedance times of an increasing additive stochastic process across independent exponential trigger variables is shown to constitute an interesting subclass of the considered distributions and yields a second probabilistic model. The alternative construction is illustrated in terms of two examples., Published at http://dx.doi.org/10.3150/14-BEJ693 in the Bernoulli (http://isi.cbs.nl/bernoulli/) by the International Statistical Institute/Bernoulli Society (http://isi.cbs.nl/BS/bshome.htm)

Direct Metal Selective Laser Sintering (DMSLS) is a layer-by-layer additive process for metal powders, which allows quick production of complex geometry parts. The aim of this study is to analyse the improvement of DMSLS with “EOSINT M270”, the new laser sintering machine developed by EOS. Tests were made on sintered parts of Direct Metal 20 (DM20), a bronze based powder with a mean grain dimension of 20 μm. Different properties and accuracy were evaluated for samples manufactured with three different exposure strategies. Besides mechanical properties, the manufacturing process was also examined in order to evaluate its characteristics. The quality of laser sintered parts is too affected by operator experience and skill. Furthermore, critical phases are not automatic and this causes an extension of time required for the production. Due to these limitations, DMSLS can be used for Rapid Manufacturing, but it is especially suitable to few sample series.

Let Xt be an arbitrary additive process taking values in ℝd. Consider \(X_{t}^{*}=\sup_{0\le s\le t}\|X_{s}\|\) and a moderate function φ. We are able to construct a function aφ(t) from the characteristics of Xt such that for all stopping times T, the ratio \(E\phi(X_{T}^{*})/Ea_{\phi}(T)\) is uniformly bounded away from 0 and ∞ by two constants depending on φ only. Let Tr=inf {t>0:‖Xt‖>r}, r>0. Similarly, we can define a function gφ(r) in terms of the characteristics of Xt such that c1gφ(r)≤Eφ(Tr)≤c2gφ(r) ∀r>0 for good constants c1, c2 depending only on φ.

Stone tool-making is a reductive process. Synthetic rock manufacturing, preeminently an additive process, will not for-ever be confined to only the Earth-biosphere. This brief focuses on humanity's ancient past, hodiernal and possible future even more massive than present-day creation of artificial rocks within our exploitable Solar System. It is mostly Earth-centric account that expands the factual generalities underlying the unique non-copyrighted systemic technogenic rock classification first publicly presented (to the American Geological Society) during 2001, by its sole intellectual innovator, James Ross Underwood, Jr. His pioneering, unique exposition of an organization of this ever-increasingly important aspect of the Anthropic Rock story, spatially expansive material lithification, here is given an amplified discussion for the broader geo and space science social group-purpose of encouragement of a completer 21st Century treatment of Underwood's explicative subject-chart (Fig. 2).

The mimimal entropy martingale measure for the stochastic process de ned as the exponential of an additive process with the structure of semimartingale will be investigated. Special attention will be paid to the case when the underlying additive process has xed times of discontinuity. The investigation of this paper will establish a uni ed way that is applicable both to the case of L evy processes and that of the sums of independent random variables.

One of the under-studied effects of global migration has been an increase in transnational marriages. This phenomenon has greatly impacted Taiwan as women from Southeast Asian nations and Mainland China, through professional marriage brokers or personal contacts, enter into marriages with Taiwanese men. How well these women adapt to Taiwan's culture and learn its local languages is studied through the lens of two theories of intercultural communication: Kim's theory of cross-cultural adaptation and Kramer's theory of cultural fusion. Based upon in-depth interviews with 28 women, results show some support for both theories. However, the postulates of cultural fusion demonstrate a better fit: Learning is an additive process; long-term association with co-ethnics appears to correlate with greater satisfaction and adaptation; and women's negotiated identities follow a range of outcomes.

In this paper, the exponential moments of R-valued additive processes with the structure of semimartingales, which are regarded as the Laplace transforms of the laws of these additive processes, will be explicitly represented by their characteristics. Note that the additive processes investigated here will not necessarily be assumed to be stochastically continuous. To prove the result, a criterion proposed in [5], which is described by the modified Laplace cumulant, will be applied.