scholarly journals Performance Analysis of MTD64, our Tiny Multi-Threaded DNS64 Server Implementation: Proof of Concept

Author(s):  
Gábor Lencse

In the current stage of IPv6 deployment, the combination of DNS64 and NAT64 is an important IPv6 transition technology, which can be used to enable IPv6 only clients to communicate with IPv4 only servers. In addition to the existing free software DNS64 implementations, we proposed a tiny multithreaded one, MTD64.In this paper, the performance of MTD64 is measured and compared to that of the industry standard BIND in order to check the correctness of the design concepts of MTD64, especially of the one that we use a new thread for each request. For the performance measurements, our earlier proposed dns64perf program is enhanced as dns64perf2, which one is also documented in this paper. We found that MTD64 seriously outperformed BIND and hence our design principles may be useful for the design of a high performance production class DNS64 server. As an additional test, we have also examined the effect of dynamic CPU frequency scaling to the performance of the implementations.

2014 ◽  
Vol 2014 ◽  
pp. 1-9 ◽  
Author(s):  
Shruti Vashist ◽  
M. K. Soni ◽  
P. K. Singhal

Rotman lenses are the beguiling devices used by the beamforming networks (BFNs). These lenses are generally used in the radar surveillance systems to see targets in multiple directions due to its multibeam capability without physically moving the antenna system. Now a days these lenses are being integrated into many radars and electronic warfare systems around the world. The antenna should be capable of producing multiple beams which can be steered without changing the orientation of the antenna. Microwave lenses are the one who support low-phase error, wideband, and wide-angle scanning. They are the true time delay (TTD) devices producing frequency independent beam steering. The emerging printed lenses in recent years have facilitated the advancement of designing high performance but low-profile, light-weight, and small-size and networks (BFNs). This paper will review and analyze various design concepts used over the years to improve the scanning capability of the lens developed by various researchers.


2019 ◽  
pp. 47-71
Author(s):  
Petr M. Mozias

China’s Belt and Road Initiative could be treated ambiguously. On the one hand, it is intended to transform the newly acquired economic potential of that country into its higher status in the world. China invites a lot of nations to build up gigantic transit corridors by joint efforts, and doing so it applies productively its capital and technologies. International transactions in RMB are also being expanded. But, on the other hand, the Belt and Road Initiative is also a necessity for China to cope with some evident problems of its current stage of development, such as industrial overcapacity, overdependence on imports of raw materials from a narrow circle of countries, and a subordinate status in global value chains. For Russia participation in the Belt and Road Initiative may be fruitful, since the very character of that project provides us with a space to manoeuvre. By now, Russian exports to China consist primarily of fuels and other commodities. More active industrial policy is needed to correct this situation . A flexible framework of the Belt and Road Initiative is more suitable for this objective to be achieved, rather than traditional forms of regional integration, such as a free trade zone.


2021 ◽  
Vol 11 (15) ◽  
pp. 6736
Author(s):  
Ong Heo ◽  
Yeowon Yoon ◽  
Jinung Do

When underground space requires excavation in areas below the water table, the foundation system suffers from buoyancy, which leads to the uplifting of the superstructure. A deep foundation system can be used; however, in cases where a hard layer is encountered, high driving forces and corresponding noises cause civil complaints in urban areas. Micropiles can be an effective alternative option, due to their high performance despite a short installation depth. Pressurized grouting is used with a packer to induce higher interfacial properties between micropile and soil. In this study, the field performance of micropiles installed using gravitational grouting or pressure-grouted using either a geotextile packer or rubber packer was comparatively evaluated by tension and creep tests. Micropiles were installed using pressure grouting in weak and fractured zones. As results, the pressure-grouted micropiles showed more stable and stronger behaviors than ones installed using the gravitational grouting. Moreover, the pressure-grouted micropile installed using the rubber packer showed better performance than the one using the geotextile packer.


Catalysts ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 163
Author(s):  
Masaru Ogura ◽  
Yumiko Shimada ◽  
Takeshi Ohnishi ◽  
Naoto Nakazawa ◽  
Yoshihiro Kubota ◽  
...  

This paper introduces a joint industries–academia–academia research project started by researchers in several automobile companies and universities working on a single theme. Our first target was to find a zeolite for NH3-SCR, that is, zeolite mining. Zeolite AFX, having the same topology of SSZ-16, was found to be the one of the zeolites. SSZ-16 can be synthesized by using an organic structure-directing agent such as 1,1′-tetramethylenebis(1-azonia-4-azabicyclo[2.2.2]octane; Dab-4, resulting in the formation of Al-rich SSZ-16 with Si/Al below five. We found that AFX crystallized by use of N,N,N′,N′-tetraethylbicyclo[2.2.2]oct-7-ene-2,3:5,6-dipyrrolidinium ion, called TEBOP in this study, had the same analog as SSZ-16 having Si/Al around six and a smaller particle size than SSZ-16. The AFX demonstrated a high performance for NH3-SCR as the zeolitic support to load a large number of divalent Cu ionic species with high hydrothermal stability.


Genetics ◽  
2003 ◽  
Vol 165 (4) ◽  
pp. 2269-2282
Author(s):  
D Mester ◽  
Y Ronin ◽  
D Minkov ◽  
E Nevo ◽  
A Korol

Abstract This article is devoted to the problem of ordering in linkage groups with many dozens or even hundreds of markers. The ordering problem belongs to the field of discrete optimization on a set of all possible orders, amounting to n!/2 for n loci; hence it is considered an NP-hard problem. Several authors attempted to employ the methods developed in the well-known traveling salesman problem (TSP) for multilocus ordering, using the assumption that for a set of linked loci the true order will be the one that minimizes the total length of the linkage group. A novel, fast, and reliable algorithm developed for the TSP and based on evolution-strategy discrete optimization was applied in this study for multilocus ordering on the basis of pairwise recombination frequencies. The quality of derived maps under various complications (dominant vs. codominant markers, marker misclassification, negative and positive interference, and missing data) was analyzed using simulated data with ∼50-400 markers. High performance of the employed algorithm allows systematic treatment of the problem of verification of the obtained multilocus orders on the basis of computing-intensive bootstrap and/or jackknife approaches for detecting and removing questionable marker scores, thereby stabilizing the resulting maps. Parallel calculation technology can easily be adopted for further acceleration of the proposed algorithm. Real data analysis (on maize chromosome 1 with 230 markers) is provided to illustrate the proposed methodology.


2014 ◽  
Vol 555 ◽  
pp. 665-672
Author(s):  
Adriana Şerban Târgoveţ ◽  
Dragoş Ionescu-Bondoc

During swimming competitions starting from the block-start platform, a potential hypothesis was noticed, through an active multimodal process, which can make the swimming start efficient, especially in the case of sprint races, by improving the propulsive force parameters of the inferior limbs. The swimming start research from interdisciplinary perspective: biomechanical, kinematic, informational and statistical can consolidate and improve the specific technique in accordance with the abilities and psycho-motor qualities of the swimmers. The present study is based on an experiment where the spatial-temporal and kinematic parameters were processed with the help of a Dartfish program. The evolution of parameters is researched as a result of a motor training program with the purpose to increase the propulsive force off the block-start. The improvement of spatial-temporal parameters influences the performance and evolution of technical parameters. Initial and final recordings were made on an MLD Station Evo5 and MLD software MuskelLeistungs Diagnose, fromSPSport, SPSportdiagnosegeräte, in order to evaluate the force, the power and the propulsive force. The argumentation of the experimental research is based on the statement: “the spatial characteristics of the motions and actions can be studied for themselves as parameters, characteristics or as a reference method for defining other characteristics, such as velocity or push-off force [1]. The main purpose of this study is to identify the influences of the specific start training upon the force improvement and kick power of the support foot from the block-start, during the classic track start. Given that the track start technique is the same as the one of the kick start executed from the international block-start of Omega, OSB11, developed in 2009, one assumes that the improvement of the classic track start leads by default to the improvement of the kick start. Lack of training to practice this type of start leads to deficient use during competitions, thus obtaining poor performances. There are no kick block-starts in Romania in order to train high performance athletes participating in international competitions and as a consequence, poor results are obtained at sprint races. One assumes that training for this type of start can be succesfully made only from a block-start similar to the kick one. The block-start model adapted by us under the same biomechanical conditions as the ones of the international kick start, is called “athletic kick”. The training specific to the kick start is carried out only with the optimum use of the kick block-start, the reasons for this being presented by N, Houel, A. Charliac, JL.Rey, Phellardin the paper: “How the swimmer could improve his track start using new Olympic plot” [2].


Energies ◽  
2018 ◽  
Vol 11 (11) ◽  
pp. 3139 ◽  
Author(s):  
Carlos Fernández Bandera ◽  
Ana Muñoz Mardones ◽  
Hu Du ◽  
Juan Echevarría Trueba ◽  
Germán Ramos Ruiz

This study presents a novel optimization methodology for choosing optimal building retrofitting strategies based on the concept of exergy analysis. The study demonstrates that the building exergy analysis may open new opportunities in the design of an optimal retrofit solution despite being a theoretical approach based on the high performance of a Carnot reverse cycle. This exergy-based solution is different from the one selected through traditional efficient retrofits where minimizing energy consumption is the primary selection criteria. The new solution connects the building with the reference environment, which acts as “an unlimited sink or unlimited sources of energy”, and it adapts the building to maximize the intake of energy resources from the reference environment. The building hosting the School of Architecture at the University of Navarra has been chosen as the case study building. The unique architectural appearance and bespoke architectural characteristics of the building limit the choices of retrofitting solutions; therefore, retrofitting solutions on the façade, roof, roof skylight and windows are considered in multi-objective optimization using the jEPlus package. It is remarkable that different retrofitting solutions have been obtained for energy-driven and exergy-driven optimization, respectively. Considering the local contexts and all possible reference environments for the building, three “unlimited sinks or unlimited sources of energy” are selected for the case study building to explore exergy-driven optimization: the external air, the ground in the surrounding area and the nearby river. The evidence shows that no matter which reference environment is chosen, an identical envelope retrofitting solution has been obtained.


Author(s):  
P. Alliot ◽  
J.-F. Delange ◽  
V. De Korver ◽  
J.-M. Sannino ◽  
A. Lekeux ◽  
...  

The intent of this publication is to provide an overview of the development of the VINCI® engine over the period 2014–2015. The VINCI® engine is an upper stage, cryogenic expander cycle engine. It combines the required features of this cycle, i. e., high performance chamber cooling and high performance hydrogen turbopump, with proven design concepts based on the accumulated experience from previous European cryogenic engines such as the HM7 and the VULCAIN®. In addition, its high performance and reliability, its restart and throttle capability offer potential applications on various future launcher upper stages as well as orbital spacecraft. At the end of 2014, the VINCI® successfully passed the Critical Design Review that was held after the major subsystem (combustion chamber, fuel and oxygen turbopump) had passed their own Critical Design Review all along the second half of 2014. In December, a Ministerial Conference at government level gave priority to the Ariane 6 program as Europe future launcher. In the framework of this decision, VINCI® was confirmed as the engine to equip Ariane 6 cryogenic upper stage engine. This publication shows how the VINCI development is progressing toward qualification, and also how the requirements of the new Ariane 6 configuration taken into account, i. e., offering new opportunities to the launch system and managing the new constraints. Moreover, the authors capitalize on the development already achieved for the evolution of Ariane 5. In parallel to completing the engine development and qualification, the configuration and the equipment of the propulsive system for Ariane 6 such as the components of the pressurization and helium command systems, board to ground coupling equipment, are being defined.


Author(s):  
Michel Bauwens ◽  
Vasilis Kostakis

Two prominent social progressive movements are faced with a few contradictions and a paradox. On the one side, we have a re-emergence of the co-operative movement and worker-owned enterprises which suffer from certain structural weaknesses. On the other, we have an emergent field of open and Commons-oriented peer production initiatives which create common pools of knowledge for the whole of humanity, but are dominated by start-ups and large multinational enterprises using the same Commons. Thus we have a paradox: the more communist the sharing license used in the peer production of free software or open hardware, the more capitalist the practice. To tackle this paradox and the aforementioned contradictions, we tentatively suggest a new convergence that would combine both Commons-oriented open peer production models with common ownership and governance models, such as those of the co-operatives and the solidarity economic models.


2018 ◽  
Vol 325 ◽  
pp. 347-358
Author(s):  
Mihai Grecu ◽  
Ilie Costaş ◽  
Artus Reaboi

Technological progress in ICT has created conditions for a new government paradigm - from a government that leads to a government providing services to society. Technology changes the nature of the connection between government and citizens: governance becomes more participatory and citizens' interests prevail. The impact of e-Government solutions is complex, on multiple levels, depending on the maturity of the models applied and the capacity of citizens and business to assimilate e-Government services. In a short time, electronic government services in Moldova have evolved from simple information services to integrated transactional services. On the one hand, this is due to high performance telecommunications infrastructure (broadband, 2G, 3G and 4G technology) and, on the other hand, to citizens' expectations that boosted recently and determined the government to accelerate the implementation of new e-services, increasingly complex and a better quality. The paper addresses the issue of e-Government services in terms of the value that it gives to the government and to citizens' lives and analyzes opportunities to develop e-Government services in the new technological and social realities.


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