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121.
Viktor Kuncak Mikaël Mayer Ruzica Piskac Philippe Suter 《International Journal on Software Tools for Technology Transfer (STTT)》2013,15(5-6):455-474
Synthesis of program fragments from specifications can make programs easier to write and easier to reason about. To integrate synthesis into programming languages, synthesis algorithms should behave in a predictable way—they should succeed for a well-defined class of specifications. To guarantee correctness and applicability to software (and not just hardware), these algorithms should also support unbounded data types, such as numbers and data structures. To obtain appropriate synthesis algorithms, we propose to generalize decision procedures into predictable and complete synthesis procedures. Such procedures are guaranteed to find the code that satisfies the specification if such code exists. Moreover, we identify conditions under which synthesis will statically decide whether the solution is guaranteed to exist and whether it is unique. We demonstrate our approach by starting from a quantifier elimination decision procedure for Boolean algebra of set with Presburger arithmetic and transforming it into a synthesis procedure. Our procedure also works in the presence of parametric coefficients. We establish results on the size and the efficiency of the synthesized code. We show that such procedures are useful as a language extension with implicit value definitions, and we show how to extend a compiler to support such definitions. Our constructs provide the benefits of synthesis to programmers, without requiring them to learn new concepts, give up a deterministic execution model, or provide code skeletons. 相似文献
122.
Mika T. Rantanen 《Journal of Intelligent and Robotic Systems》2011,64(2):161-178
The motion planning is a difficult problem but nevertheless, a crucial part of robotics. The probabilistic roadmap planners
have shown to be an efficient way to solve these planning problems. In this paper, we present a new algorithm that is based
on the principles of the probabilistic roadmap planners. Our algorithm enhances the sampling by intelligently detecting which
areas of the configuration space are easy and which parts are not. The algorithm then biases the sampling only to the difficult
areas that may contain narrow passages. Our algorithm works by dividing the configuration space into regions at the beginning
and then sampling configurations inside each region. Based on the connectivity of the roadmap inside each region, our algorithm
aims to detect whether the region is easy or difficult. We tested our algorithm with three different simulated environments
and compared it with two other planners. Our experiments showed that with our method it is possible to achieve significantly
better results than with other tested planners. Our algorithm was also able to reduce the size of roadmaps. 相似文献
123.
Nohara Goto Hiroyuki Suzuki Tomohiro Tanaka Teizo Asano Mika K. Kaneko Yukinari Kato 《International journal of molecular sciences》2022,23(10)
CD44 is a cell surface glycoprotein, which is expressed on normal cells, and overexpressed on cancer cells. CD44 is involved in cell adhesion, migration, proliferation, survival, stemness, and chemo−resistance. Therefore, CD44 is thought to be a promising target for cancer diagnosis and therapy. In this study, we established anti−CD44 monoclonal antibodies (mAbs) by immunizing mice with a CD44 variant (CD44v3−10) ectodomain and screening using enzyme−linked immunosorbent assay. We then characterized them using flow cytometry, Western blotting, and immunohistochemistry. One of the established clones (C44Mab−46; IgG1, kappa) reacted with CD44 standard isoform (CD44s)−overexpressed Chinese hamster ovary−K1 cells (CHO/CD44s) or esophageal squamous cell carcinoma (ESCC) cell lines (KYSE70 and KYSE770). The apparent KD of C44Mab−46 for CHO/CD44s, KYSE70, and KYSE770 was 1.1 × 10−8 M, 4.9 × 10−8 M, and 4.1 × 10−8 M, respectively. C44Mab−46 detected CD44s of CHO/CD44s and KYSE70, and CD44 variants of KYSE770 in Western blot analysis. Furthermore, C44Mab−46 strongly stained the formalin−fixed paraffin−embedded ESCC tissues in immunohistochemistry. Collectively, C44Mab−46 is very useful for detecting CD44 in various applications. 相似文献
124.
Plenty of technical norms, included in the EPBD umbrella, assesses the performance of buildings or its sub-systems in terms of efficiency. In particular, EN 15316 and its sub-sections determine the efficiency factors of a space heating system. This paper focuses on the estimation of efficiency factors for hydronic panel radiators. The assessment of efficiency factors occurs by evaluating the amount of heat emitted from the heat emitter and the thermal losses towards building envelope. A factor that influences the heat emitted is the location of radiator connection pipes. Connection pipes can be located on opposite side or at the same side of the radiator. To better estimate the heat emitted from the radiator with different location of connection pipes, a transient model with multiple storage elements is implemented in a commercial building simulation software and validated versus available experimental measurements. Sensitivity analysis encompasses the variations of heat losses due to the building location in different climates, the changing of the active thermal mass and the type of radiator local control. The final outcome of this paper is a practical support where designers and researchers can easily assess the efficiency factors for space heating system equipped with hydronic panel radiators of buildings located in Sweden. As main results, (i) the efficiency factor for control is higher in Northern climates (Luleå) than in Southern climates (Gothenburg), (ii) heavy-weight active thermal masses allow higher efficiency factors than light active thermal masses, and (iii) connection pipes located on the same side of the hydronic panel radiator enable higher efficiency factors than pipes located on opposite side. 相似文献
125.
Lanthanide and Heavy Metal Free Long White Persistent Luminescence from Ti Doped Li–Hackmanite: A Versatile,Low‐Cost Material 下载免费PDF全文
Isabella Norrbo José M. Carvalho Pekka Laukkanen Jaakko Mäkelä Fikret Mamedov Markus Peurla Hanna Helminen Sari Pihlasalo Harri Härmä Jari Sinkkonen Mika Lastusaari 《Advanced functional materials》2017,27(17)
Persistent luminescence (PeL) materials are used in everyday glow‐in‐the‐dark applications and they show high potential for, e.g., medical imaging, night‐vision surveillance, and enhancement of solar cells. However, the best performing materials contain rare earths and/or other heavy metal and expensive elements such as Ga and Ge, increasing the production costs. Here, (Li,Na)8Al6Si6O24(Cl,S)2:Ti, a heavy‐metal‐ and rare‐earth‐free low‐cost material is presented. It can give white PeL that stays 7 h above the 0.3 mcd m?2 limit and is observable for more than 100 h with a spectrometer. This is a record‐long duration for white PeL and visible PeL without rare earths. The material has great potential to be applied in white light emitting devices (LEDs) combined with self‐sustained night vision using only a single phosphor. The material also exhibits PeL in aqueous suspensions and is capable of showing easily detectable photoluminescence even in nanomolar concentrations, indicating potential for use as a diagnostic marker. Because it is excitable with sunlight, this material is expected to additionally be well‐suited for outdoor applications. 相似文献
126.
Alina A. Manshina Alexey V. Povolotskiy Anastasia V. Povolotskaya Tatiana Yu. Ivanova Igor O. Koshevoy Sergey P. Tunik Mika Suvanto Tapani A. Pakkanen 《Surface & coatings technology》2012
Heterometallic (Au–Cu) phase precipitation on the surface of soda-lime glass as a result of laser-induced chemical liquid phase deposition (LCLD) is demonstrated for the first time. The precipitation of heterometallic structures was carried out under Ar+ laser irradiation from the solutions of supramolecular complexes. Energy dispersive X-ray (EDX) analysis showed that the deposits consist of both Au and Cu. Morphology of the deposited structures was found to be dependent on the used solvents: delocalized sparse surface structures in the case of the dichloromethane solution, close packed nanoparticles for the dimethyl formamide and homogeneous phase with nano-pores for the acetone solution. In accordance to the SEM photos and scan EDX analysis the homogeneous heterometallic phase with fixed Au/Cu ratio was achieved for the acetone solution of supramolecular complex. The observed formation of the heterometallic phase was explained by the laser-initiated intramolecular reduction process of the supramolecular metal core. 相似文献
127.
Pirjo Heikkilä Terhi Hirvikorpi Heidi Hilden Jenni Sievänen Leo Hyvärinen Ali Harlin Mika Vähä-Nissi 《Journal of Materials Science》2012,47(8):3607-3612
Novel nanostructured and high surface area tubular materials were produced combining electrospinning and atomic layer deposition
processes with the removal of polymeric template via dissolution. The dissolution process changed the structure of the tube
walls, and the smooth atomic layer deposition coating was transformed into a highly complex, coral-like structure. This material,
which we have called “nanocoral,” has a relatively high surface area, 323 m2 g−1, due to the interconnected cavities formed after the removal of the template. This kind of material has important potential
applications, for example, in the fields of catalysts and filtration. 相似文献
128.
Alloying secondary hardening steels with Ni and Al allows the precipitation of an intermetallic phase B2-NiAl in addition
to the classical secondary carbides precipitation, adding up the advantages of both types of precipitation (Erlach et al.
Mater Sci Eng A 429:96, 2006; Erlach et al. Int J Microstruct Mater Prop 3:373, 2008). Small-angle neutron scattering experiments were carried out to analyse the nanometric scale precipitation of a martensitic
steel containing a double precipitation of carbides and intermetallic phase. The precipitates size, volume fraction and chemical
composition for both carbides and intermetallic phases according to the tempering time were estimated and discussed. In addition,
experimental cobalt-free grades containing a single precipitation or a double precipitation were manufactured and analysed.
Relationship between measured tensile yield strengths and the nanometre-sized particles are suggested, showing that both populations
of precipitates have a relevant impact on the mechanical properties. 相似文献
129.
In this paper, the optimal process parameters of a wave soldering process were defined. The optimization was performed in respect to soldering quality by minimizing a cost function describing the total repairing cost of a wave-soldered printed circuit board (PCB). The data analysis stages were as follows. First, the process data were coded into inputs for a self-organizing map (SOM). Next, a function for the repairing cost was constructed and used to find the optimal map neurons. At the last phase, the optimal parameters were approximated on the basis of the reference vectors of the optimal neurons. The results showed clearly potential in the optimization of the wave soldering process, especially in the visualization of the optimal process conditions. Therefore, it would be useful to exploit the method more widely in the electronics industry. 相似文献
130.
Takashi Nagamine Takahiro Sekiwa Emiko Yamaguchi Mika Oozeki Tsuneo Kato 《Journal of the Institute of Brewing》2009,115(4):292-295
To make an efficient and laborsaving quality selection in a malting barley breeding program, the relationship between malting quality parameters and the hardness index (HI) measured by Single Kernel Characterization System (SKCS) 4100 was studied with barley genetic resources and a group of descendant lines from “Yon Rkei 1363” that possess the high lysine allele lys1 and a very high diastatic power (DP). There was a highly significant correlation between the grain HI and the malt extract both in the genetic resources (r = ?0.48**) and in the lys1 parent‐derived lines (r = ?0.50**). Malt HI showed a highly significant correlation with malt extract (r = ?0.70** in genetic resources, r = ?0.57** in the lys1 parent‐derived lines) and malt total protein (r = 0.73**, 0.84**, respectively). For the selection of very high DP lines from the lys1 parent‐derived group, high grain HI selection was effective as all the very high DP lines had much harder grain characteristics. Therefore SKCS was regarded as a useful tool for quality selection in malting barley breeding. 相似文献