c++ [1, 2] extends a modern, general purpose programming language into the object-oriented programming paradigm. The language ameliorates disadvatanges of c while introducing new problems. Advantages and disadvantages...
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c++ [1, 2] extends a modern, general purpose programming language into the object-oriented programming paradigm. The language ameliorates disadvatanges of c while introducing new problems. Advantages and disadvantages of traditional c [3, 4] have been discussed in [5]. This paper assesses c++, examining why it is better general purpose programming langauge. Since c++ is “object-oriented” we consider how well it implements that metaphor. In this paper we assume the reader has a working knowledge of the c programming language. Section 1 briefly enumerates advantages and disadvantages of c to provide a context for assessing c++. In Section 2 we describe new c++ features and discuss ways they ameliorate shortcomings of c. Section 3 describes philosophical and practical problems with c++. The last section assesses c++ as a successor to c.
A one-pot synthesis of substituted (dihydro)thieno[2,3-c]chromene derivatives was developed through a Lewis base catalyzed domino Michael addition/intramolecular cyclization reaction between 3-nitro-2H -chromenes and ...
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A one-pot synthesis of substituted (dihydro)thieno[2,3-c]chromene derivatives was developed through a Lewis base catalyzed domino Michael addition/intramolecular cyclization reaction between 3-nitro-2H -chromenes and thioamides. The desired (dihydro)thieno[2,3-c]chromene derivatives were prepared with a large substrate scope (22 examples) and excellent diastereoselectivity in moderate to excellent yields.
Systems code is almost universally written in the c programming language or a variant. c has a very low level of type and memory abstraction and formal reasoning about c systems code requires a memory model that is ab...
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Systems code is almost universally written in the c programming language or a variant. c has a very low level of type and memory abstraction and formal reasoning about c systems code requires a memory model that is able to capture the semantics of c pointers and types. At the same time, proof-based verification demands abstraction, in particular from the aliasing and frame problems. In this paper we present a study in the mechanisation of two proof abstractions for pointer program verification in the Isabelle/HOL theorem prover, based on a low-level memory model for c. The language's type system presents challenges for the multiple independent typed heaps (Burstall-Bornat) and separation logic proof techniques. In addition to issues arising from explicit value size/alignment, padding, type-unsafe casts and pointer address arithmetic, structured types such as c's arrays and structs are problematic due to the non-monotonic nature of pointer and lvalue validity in the presence of the unary &-operator. For example, type-safe updates through pointers to fields of a struct break the independence of updates across typed heaps or a (*)-conjuncts. We provide models and rules that are able to cope with these language features and types, eschewing common over-simplifications and utilising expressive shallow embeddings in higher-order logic. Two case studies are provided that demonstrate the applicability of the mechanised models to real-world systems code;a working of the standard in-place list reversal example and an overview of the verification of the L4 microkernel's memory allocator.
We address the problem of estimating the carrier-to-noise ratio (c/N-0) in weak signal conditions. There are several environments, such as forested areas, indoor buildings and urban canyons, where high-sensitivity glo...
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We address the problem of estimating the carrier-to-noise ratio (c/N-0) in weak signal conditions. There are several environments, such as forested areas, indoor buildings and urban canyons, where high-sensitivity global navigation satellite system (HS-GNSS) receivers are expected to work under these reception conditions. The acquisition of weak signals from the satellites requires the use of post-detection integration (PDI) techniques to accumulate enough energy to detect them. However, due to the attenuation suffered by these signals, estimating their c/N-0 becomes a challenge. Measurements of c/N-0 are important in many applications of HS-GNSS receivers such as the determination of a detection threshold or the mitigation of near-far problems. For this reason, different techniques have been proposed in the literature to estimate the c/N-0, but they only work properly in the high c/N-0 region where the coherent integration is enough to acquire the satellites. We derive four c/N-0 estimators that are specially designed for HS-GNSS snapshot receivers and only use the output of a PDI technique to perform the estimation. We consider four PDI techniques, namely non-coherent PDI, non-quadratic non-coherent PDI, differential PDI and truncated generalized PDI and we obtain the corresponding c/N-0 estimator for each of them. Our performance analysis shows a significant advantage of the proposed estimators with respect to other c/N-0 estimators available in the literature in terms of estimation accuracy and computational resources.
A significant correlation between the in-plane (IP) and out-of-plane (OOP) damage propagation of masonry infills (MIs) is frequently observed after strong earthquakes, posing a serious problem as regards vulnerability...
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A significant correlation between the in-plane (IP) and out-of-plane (OOP) damage propagation of masonry infills (MIs) is frequently observed after strong earthquakes, posing a serious problem as regards vulnerability of public buildings such as schools. The present work is aimed at identifying the effects of different IP and OOP modelling assumptions of MIs on their seismic damage. To this end, the state secondary school De Gasperi-Battaglia in Norcia (Italy), object of monitoring by the Department of civil Protection since 2000, is investigated for the heterogeneity of infill typologies. The school is composed of a basement and three storeys above ground level, with a reinforced concrete (r.c.) framed structure having a long-shaped rectangular plan. Two typologies can be identified in terms of transverse layout of MIs: (i) double-leaf interior partitions, made of hollow clay bricks;(ii) double-leaf exterior infill walls, constituted by facade solid bricks paired with hollow clay bricks. In addition, partial height infills in the longitudinal direction, due to classroom windows, make the columns susceptible to short column effects. MIs are represented by a five-element macro-model predicting both in-plane (IP) and out-of-plane (OOP) behaviour through a horizontal nonlinear truss and four diagonal nonlinear beam elements, respectively. Stiffness and strength values in the OOP direction are also reduced considering the evolution of the IP damage. Three assumptions are investigated for the behaviour of structural MIs: i.e. elastic both IP and OOP;inelastic IP and elastic OOP;inelastic both IP and OOP. Bare and infilled test structures are subjected to biaxial spectrum-compatible accelerograms, to evaluate the IP and OOP damage levels and effectiveness of the OOP simplified verification proposed by seismiccodes.
corynebacterium glutamicum is the major workhorse for the microbial production of several amino and organic acids. As long as these derive from tricarboxylic acid cycle intermediates, the activity of anaplerotic react...
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corynebacterium glutamicum is the major workhorse for the microbial production of several amino and organic acids. As long as these derive from tricarboxylic acid cycle intermediates, the activity of anaplerotic reactions is pivotal for a high biosynthetic yield. To determine single anaplerotic activities c-13-Metabolic Flux Analysis (c-13-MFA) has been extensively used for c. glutamicum, however with different network topologies, inconsistent or poorly determined anaplerotic reaction rates. Therefore, in this study we set out to investigate whether a focused isotopomer model of the anaplerotic node can at all admit a unique solution for all fluxes. By analyzing different scenarios of active anaplerotic reactions, we show in full generality that for c. glutamicum only certain anaplerotic deletion mutants allow to uniquely determine the anaplerotic fluxes from c-13-isotopomer data. We stress that the result of this analysis for different assumptions on active enzymes is directly transferable to other compartment-free organisms. Our results demonstrate that there exist biologically relevant metabolic network topologies for which the flux distribution cannot be inferred by classical c-13-MFA. Biotechnol. Bioeng. 2016;113: 661-674. (c) 2015 Wiley Periodicals, Inc.
Superior electrode materials play a key role on the electrochemical performance for the lithium-ion batteries and supercapacitors. The co3O4-based materials are promising electrode materials due to their high specific...
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Superior electrode materials play a key role on the electrochemical performance for the lithium-ion batteries and supercapacitors. The co3O4-based materials are promising electrode materials due to their high specificcapacity and energy density. However, the poor cycle performance limits their applications during the process of the commercialization for the lithium-ion batteries and supercapacitors. Because of the poor cycle stability, c, N co-doped co3O4 hollow spheres are successfully prepared and used as electrode materials for the lithium-ion batteries and supercapacitors. Via the c, N co-doping process, the electronicconductivity is greatly improved. Moreover, the hollow structure could ensure the structural stability during the electrochemical process. As a result, the cycle performance and specificcapacity are greatly improved when the c, N co-doped co3O4 composites are used as electrode materials for the lithium-ion batteries and supercapacitors. (c) 2019 Hydrogen Energy Publications LLc. Published by Elsevier Ltd. All rights reserved.
OpencL is an open standard for parallel programming of heterogeneous compute devices, such as GPUs, cPUs, DSPs or FPGAs. However, the verbosity of its c host API can hinder application development. In this paper we pr...
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OpencL is an open standard for parallel programming of heterogeneous compute devices, such as GPUs, cPUs, DSPs or FPGAs. However, the verbosity of its c host API can hinder application development. In this paper we present cf4ocl, a software library for rapid development of OpencL programs in pure c. It aims to reduce the verbosity of the OpencL API, offering straightforward memory management, integrated profiling of events (e.g., kernel execution and data transfers), simple but extensible device selection mechanism and user-friendly error management. We compare two versions of a conceptual application example, one based on cf4ocl, the other developed directly with the OpencL host API. Results show that the former is simpler to implement and offers more features, at the cost of an effectively negligible computational overhead. Additionally, the tools provided with cf4ocl allowed for a quick analysis on how to optimize the application. (c) 2017 Elsevier B.V. All rights reserved.
Protein kinase c (PKc) has a crucial role in signal transduction for a variety of biologically active substances which activate cellular functions and proliferation. We previously isolated the full-length PKc gene fro...
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Protein kinase c (PKc) has a crucial role in signal transduction for a variety of biologically active substances which activate cellular functions and proliferation. We previously isolated the full-length PKc gene from Dunaliella salina (DsPKc) using rapid amplification of cDNA ends (RAcE) and RT-PcR methods. And we submitted the mRNA sequence of DsPKc gene to NcBI (Genbank No. JN625213). In the present paper, the DsPKc gene open reading frame obtained by PcR was cloned into pGS-21a vector and transformed into Escherichia coli to generate the fusion protein. Bioinformatics analysis revealed that DsPKc gene was a member of serine/threonine kinase with two conserved domains and highly conserved motifs. The DsPKc was highly expressed upon induction with isopropyl-β-d-thiogalactoside (IPTG) at a final concentration of 0.2 mmol L 1 at 37℃. Under salt stress, the fu- sion protein Green Fluorescent Protein (GFP)-DsPKc was transferred from the cytoplasm to the cell membrane. The expression pat- tern of DsPKc gene was analyzed using real-time quantitative PcR, and indicated that DsPKc gene was up-regulated by 3.0 mol L 1 Nacl at 12 h, which was significantly higher than in control values (P < 0.05). These results suggest that the DsPKc gene plays an important role in response to salt stress in D. salina.
An investigation was carried out on the reaction process and mechanism between K 2TiF 6, graphite powder and aluminum melt with the common Ti concentration of 5%～7% in the grain refiner Al Ti c master alloys and the ...
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An investigation was carried out on the reaction process and mechanism between K 2TiF 6, graphite powder and aluminum melt with the common Ti concentration of 5%～7% in the grain refiner Al Ti c master alloys and the reaction temperature of 750～950 ℃, aiming at understanding their reaction mechanism and putting forward the aluminothermal reduction reaction method to practical use. During experimental investigation, K 2TiF 6 and graphite wrapped in aluminum foils were introduced into the aluminum melt at 850 ℃. Samples of alloy and slag were investigated by chemical analysis, XRD examination, SEM observation, and EDS analysis as well. It was found that the reaction was very vigorous at the beginning of the process and then reached a dynamic equilibrium. There were 3 particular reactions during the aluminothermal reaction process. At the beginning stage of the reaction, there emerged the phases of Tic and one type of metastable intermetallic phase TiAl 9 as well as TiAl 3 in aluminum melt. At the late stage of the reaction, the metastable phase TiAl 9 disappeared and another phase of Al 4c 3 emerged.
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