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151.
Interfacial reactions between liquid Sn and various Cu-Ni alloy metallizations as well as the subsequent phase transformations
during the cooling were investigated with an emphasis on the microstructures of the reaction zones. It was found that the
extent of the microstructurally complex reaction layer (during reflow at 240°C) does not depend linearly on the Ni content
of the alloy metallization. On the contrary, when Cu is alloyed with Ni, the rate of thickness change of the total reaction
layer first increases and reaches a maximum at a composition of about 10 at.% Ni. The reaction layer is composed of a relatively
uniform continuous (Cu,Ni)6Sn5 reaction layer (a uniphase layer) next to the NiCu metallizations and is followed by the two-phase solidification structures
between the single-phase layer and Sn matrix. The thickness of the two-phase layer, where the intermetallic tubes and fibers
have grown from the continuous interfacial (Cu,Ni)6Sn5 layer, varies with the Ni-to-Cu ratio of the alloy metallization. In order to explain the formation mechanism of the reaction
layers and their observed kinetics, the phase equilibria in the Sn-rich side of the SnCuNi system at 240°C were evaluated
thermodynamically utilizing the available data, and the results of the Sn/Cu
x
Ni1−x
diffusion couple experiments. With the help of the assessed data, one can also evaluate the minimum Cu content of Sn-(Ag)-Cu
solder, at which (Ni,Cu)3Sn4 transforms into (Cu,Ni)6Sn5, as a function of temperature and the composition of the liquid solders. 相似文献
152.
Valeria Tafintseva Tiril Aurora Lintvedt Johanne Heitmann Solheim Boris Zimmermann Hafeez Ur Rehman Vesa Virtanen Rubina Shaikh Ervin Nippolainen Isaac Afara Simo Saarakkala Lassi Rieppo Patrick Krebs Polina Fomina Boris Mizaikoff Achim Kohler 《Molecules (Basel, Switzerland)》2022,27(3)
The aim of the study was to optimize preprocessing of sparse infrared spectral data. The sparse data were obtained by reducing broadband Fourier transform infrared attenuated total reflectance spectra of bovine and human cartilage, as well as of simulated spectral data, comprising several thousand spectral variables into datasets comprising only seven spectral variables. Different preprocessing approaches were compared, including simple baseline correction and normalization procedures, and model-based preprocessing, such as multiplicative signal correction (MSC). The optimal preprocessing was selected based on the quality of classification models established by partial least squares discriminant analysis for discriminating healthy and damaged cartilage samples. The best results for the sparse data were obtained by preprocessing using a baseline offset correction at 1800 cm−1, followed by peak normalization at 850 cm−1 and preprocessing by MSC. 相似文献
153.
Ijaz Ahmad Tanesh Kumar Madhusanka Liyanage Mika Ylianttila Timo Koskela Timo Braysy Antti Anttonen Vesa Pentikinen Juha- Pekka Soininen Jyrki Huusko 《Telematics and Informatics》2018,35(1):82-92
This paper presents a roadmap for the transition from current gadget-centric digital services towards a gadget-free services environment called the Naked world. The main idea of the Naked world is that all the services which are currently provided by gadgets will be provided by the infrastructure, thus no gadgets will be needed to use any kind of digital services. When a user in the Naked world intends to use a service, the infrastructure senses the user, the nearby intelligent surrounding launches an interactive user interface, performs identification through biometric identities, provides the service, and then closes the session when the user finishes the job. Therefore, the Naked world comprises highly intelligent and context-aware interactive environments. The vision of the Naked world is an evolution towards a user-friendly and ubiquitously available digital services, which is naturally bounded by the technological advancement. Henceforth, this paper presents the essential technologies and functional requirements along with the current and forthcoming novel technological concepts and challenges for the realization of the Naked world. 相似文献
154.
Russian doll search is applied to finding maximum independent sets in hypergraphs, focusing on a particular subproblem of
the hitting set problem, the Steiner triple covering problem. An instance denoted A
135 is solved considerably faster with Russian doll search than with integer linear programming and a state-of-the-art optimization
tool (using otherwise a similar established approach to split the problem into subproblems). In addition, the improvement
in speed makes it possible to carry out a search proving that all optimal solutions for A
135 are isomorphic. 相似文献
155.
Simona Bungau Cosmin Mihai Vesa Areha Abid Tapan Behl Delia Mirela Tit Anamaria Lavinia Purza Bianca Pasca Laura Maghiar Todan Laura Endres 《Molecules (Basel, Switzerland)》2021,26(9)
Withaferin A (WFA) was identified as the most active phytocompound of the plant Withania somnifera (WS) and as having multiple therapeutic/ameliorating properties (anticancer, antiangiogenic, anti-invasive, anti-inflammatory, proapoptotic, etc.) in case of various diseases. In drug chemistry, WFA in silico approaches have identified favorite biological targets, stimulating and accelerating research to evaluate its pharmacological activity—numerous anticancer effects manifested in various organs (breast, pancreas, skin, colon, etc.), antivirals, anti-infective, etc., which are not yet sufficiently explored. This paper is a synthesis of the most relevant specialized papers in the field that are focused on the use of WFA in dermatological diseases, describing its mechanism of action while providing, at the same time, details about the results of its testing in in vitro/in vivo studies. 相似文献
156.
Raili Pönni Timo Pääkkönen Markus Nuopponen Jaakko Pere Tapani Vuorinen 《Cellulose (London, England)》2014,21(4):2859-2869
Alkali treatment was used to increase the reactivity of birch kraft pulp prior to its 2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO) catalyzed oxidation with hypochlorite, which is a process commonly applied to prepare nanofibrillated cellulose. On contrary to the traditional use of NaBr as a cocatalyst, TEMPO was activated with HOCl prior to the oxidation. Commonly, the lack of bromide increases the oxidation time and impairs the formation of carboxylic groups. However, the reaction time of the bromide-free TEMPO catalyzed oxidation could be shortened from 2.5 to 0.5 h when the pulp was treated with 1 M NaOH prior to the oxidation (2.4 mmol NaOCl/g pulp). The beneficial effect was obtained even if the alkali treatment was executed at room temperature and only for few minutes. Moreover, the alkali pretreatment enabled selective production of a pulp with carboxylate content as high as 1.6 mmol/g with NaOCl dosage of 4.4 mmol/g. The changes in the cellulosic raw material during the alkali treatment were assessed by water retention value and carbohydrate analysis. 相似文献
157.
Erno Salminen Tero Kangas Timo D. H?m?l?inen Jouni Riihim?ki Vesa Lahtinen Kimmo Kuusilinna 《The Journal of VLSI Signal Processing》2006,43(2-3):185-205
This paper presents a communication network targeted for complex system-on-chip (SoC) and network-on-chip (NoC) designs. The
Heterogeneous IP Block Interconnection (HIBI) aims at maximum efficiency and minimum energy per transmitted bit combined with
quality-of-service (QoS) in transfers. Other features include support for hierarchical topologies with several clock domains,
flexible scalability, and runtime reconfiguration of network parameters. HIBI is intended for integrating coarse-grain components
such as intellectual property (IP) blocks that have size of thousands of gates.HIBI has been implemented in VHDL and SystemC
and synthesized on several CMOS technologies and on FPGA. A 32-bit wrapper requires 5400 gates and runs with 315 MHz on 0.18
μ m technology which shows that only minimal area overhead is paid for the advanced features. The area and frequency results
are well comparable to other NoC proposals.Furthermore, data transfers are shown to approach the maximum theoretical performance
for protocol efficiency. HIBI network is accompanied with a design framework with tools for optimizing the system through
automated design space exploration.
Erno Salminen Tampere University of Technology (TUT), Finland.Currently he is working towards his PhD degree in the Institute of Digital
and Computer Systems (DCS) at TUT. His main research interests are digital systems design and communication issues in SoCs.
Tero KangasTampere University of Technology (TUT), Finland.Since 1999 he has been working as a research scientist in the Institute of
Digital and Computer Systems (DCS) at TUT. Currently he is working towards his PhD degree and his main research topics are
system architectures and SoC design methodologies in multimedia applications.
Timo D. H?m?al?ainen Tampere University of Technology (TUT), Finland. He was nominated to full professor at TUT/Institute of Digital and Computer
Systems in 2001. He heads the DACI research group that focuses on three main research areas: wireless sensor networks, high-performance
multi-DSP and hardware based video encoding, and design flow tools for heterogeneous MP-SoC platforms.
Jouni Riihi?mki Tampere University of Technology (TUT), Finland. Currently he is working as a senior design engineer at Nokia Technlogy Platforms.
He is also working towards his PhD degree. His research interests include SoC design and verification methodologies.
Vesa Lahtinen received his M.Sc. and Ph.D. from TUT in 1998 and 2004, respectively. In TUT, his main research areas were system-on-chips
and their interconnects. Currently, Dr. Lahtinen is a Senior Research Engineer in the Computing Architectures Laboratory of
Nokia Research Center (NRC) concentrating on architecture modeling and, specifically, memory architectures.
Kimmo Kuusilinna Tampere University of Technology (TUT), Finland. His main research interests include system-level design and verification,
on-chip interconnections, and parallel memories. Currently he is working as a senior research engineer at the Nokia Research
Center. 相似文献
158.
An algorithmic solution to Teichmüller's extremal ring problem is given. 相似文献
159.
We show that it is undecidable for finite sets S of upper triangular (4×4)-matrices over Z[x,x−1] whether or not all elements in the semigroup generated by S have a nonzero constant term in some of the Laurent polynomials of the first row. This result follows from a representations of the integer weighted finite automata by matrices over Laurent polynomials. 相似文献
160.
I. V. Gofman E. M. Ivan’kova I. V. Abalov V. E. Smirnova E. N. Popova O. Orell J. Vuorinen V. E. Yudin 《Polymer Science Series A》2016,58(1):87-94
A comparative study of the effects of various nanoparticles introduced into polyetherimide Ultem-1000 (Sabic)—such as carbon nanofibers, nanocones/discs, halloysite hydrosilicate nanotubes, and quasispherical zirconia particles doped with yttria―on the mechanical behavior of nanocomposites is performed. The introduction of nanoparticles into the polymer increases the Young’s moduli and yield stress of block materials relative to those of the unfilled polymeric material. These effects make themselves more pronounced with an increase in temperature, especially when сarbon nanocones/discs are used as a filler. The collected data are commensurable with the electron-microscopic study of the morphology of the material and its densitometry measurements, which make it possible to estimate the values of excess free volume in the studied composite materials, as well as with the previous data on the incorporation of analogous nanoparticles into polypyromellitimide films. 相似文献