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SRAM or Static Random-Access Memory is the most vital memory technology. SRAM is fast and robust but faces design challenges in nanoscale CMOS such as high leakage, power consumption, and reliability. Quantum-dot Cellular Automata (QCA) is the alternative technology that can be used to address the challenges of conventional SRAM. In this paper, a cost-efficient single layer SRAM cell has been proposed in QCA. The design has 39 cells with a latency of 1.5 clock cycles and achieves an overall improvement in cell count, area, latency, and QCA cost compared to the reported designs. It can therefore be used to design nanoscale memory structures of higher order. Validerad;2023;Nivå 2;2023-02-08 (joosat);Licens fulltext: CC BY License

Reliability and cost are two important targets for distributed storage systems. For many years, numerous schemes have been proposed to improve the reliability or cost of distributed storage systems, and they can be divided into three categories: (1) data redundancy schemes; (2) data placement schemes; and (3) data repair schemes. However, it is still unclear regarding how to build a reliable and cost-efficient distributed storage system, because (i) insufficient considerations on the combinations of different schemes; and (ii) insufficient considerations on failures and recoveries of different subsystems (racks, nodes, disks, and sectors). To measure the reliability and cost caused by different schemes, we design and implement CR-SIM, a Comprehensive Reliability SIMulator for distributed storage systems. It considers various affecting factors, such as the system topology, the data redundancy scheme, the data placement scheme, the data repair scheme, and the failure/recovery models of different subsystems. By using CR-SIM, we conduct various simulation-based experiments, and the experimental results reveal several important findings, which are helpful to build reliable and cost-efficient distributed storage systems. For public use, we have open-sourced our source code at https://github.com/yichuan0707/CR-SIM.

Background: A good search strategy is essential for a successful systematic literature study. Historically, database searches have been the norm, which was later complemented with snowball searches. Our conjecture is that we can perform even better searches if combining these two search approaches, referred to as a hybrid search strategy. Objective: Our main objective was to compare and evaluate a hybrid search strategy. Furthermore, we compared four alternative hybrid search strategies to assess whether we could identify more cost-efficient ways of searching for relevant primary studies. Methods: To compare and evaluate the hybrid search strategy, we replicated the search procedure in a systematic literature review (SLR) on industry–academia collaboration in software engineering. The SLR used a more “traditional” approach to searching for relevant articles for an SLR, while our replication was executed using a hybrid search strategy. Results: In our evaluation, the hybrid search strategy was superior in identifying relevant primary studies. It identified 30% more primary studies and even more studies when focusing only on peer-reviewed articles. To embrace individual viewpoints when assessing research articles and minimise the risk of missing primary studies, we introduced two new concepts, wild cards and borderline articles, when performing systematic literature studies. Conclusions: The hybrid search strategy is a strong contender for being used when performing systematic literature studies. Furthermore, alternative hybrid search strategies may be viable if selected wisely in relation to the start set for snowballing. Finally, the two new concepts were judged as essential to cater for different individual judgements and to minimise the risk of excluding primary studies that ought to be included. © 2022 The Authors open access

Altres ajuts: EC Copernicus Global Land Service (CGLOPS-1, 199494-JRC). Spatiotemporally representative Elementary Sampling Units (ESUs) are required for capturing the temporal variations in surface spatial heterogeneity through field measurements. Since inaccessibility often coexists with heterogeneity, a cost-efficient sampling design is mandatory. We proposed a sampling strategy to generate spatiotemporally representative and cost-efficient ESUs based on the conditioned Latin hypercube sampling scheme. The proposed strategy was constrained by multi-temporal Normalized Difference Vegetation Index (NDVI) imagery, and the ESUs were limited within a sampling feasible region established based on accessibility criteria. A novel criterion based on the Overlapping Area (OA) between the NDVI frequency distribution histogram from the sampled ESUs and that from the entire study area was used to assess the sampling efficiency. A case study inWanglang National Nature Reserve in China showed that the proposed strategy improves the spatiotemporally representativeness of sampling (mean annual OA = 74.7%) compared to the single-temporally constrained (OA = 68.7%) and the random sampling (OA = 63.1%) strategies. The introduction of the feasible region constraint significantly reduces in-situ labour-intensive characterization necessities at expenses of about 9% loss in the spatiotemporal representativeness of the sampling. Our study will support the validation activities in Wanglang experimental site providing a benchmark for locating the nodes of automatic observation systems (e.g., LAINet) which need a spatially distributed and temporally fixed sampling design.

Fillet yield (FY) and harvest weight (HW) are economically important traits in Nile tilapia production. Genetic improvement of these traits, especially for FY, are lacking, due to the absence of efficient methods to measure the traits without sacrificing fish and the use of information from relatives to selection. However, genomic information could be used by genomic selection to improve traits that are difficult to measure directly in selection candidates, as in the case of FY. The objectives of this study were: (i) to perform genome-wide association studies (GWAS) to dissect the genetic architecture of FY and HW, (ii) to evaluate the accuracy of genotype imputation and (iii) to assess the accuracy of genomic selection using true and imputed low-density (LD) single nucleotide polymorphism (SNP) panels to determine a cost-effective strategy for practical implementation of genomic information in tilapia breeding programs. The data set consisted of 5,866 phenotyped animals and 1,238 genotyped animals (108 parents and 1,130 offspring) using a 50K SNP panel. The GWAS were performed using all genotyped and phenotyped animals. The genotyped imputation was performed from LD panels (LD0.5K, LD1K and LD3K) to high-density panel (HD), using information from parents and 20% of offspring in the reference set and the remaining 80% in the validation set. In addition, we tested the accuracy of genomic selection using true and imputed genotypes comparing the accuracy obtained from pedigree-based best linear unbiased prediction (PBLUP) and genomic predictions. The results from GWAS supports evidence of the polygenic nature of FY and HW. The accuracy of imputation ranged from 0.90 to 0.98 for LD0.5K and LD3K, respectively. The accuracy of genomic prediction outperformed the estimated breeding value from PBLUP. The use of imputation for genomic selection resulted in an increased relative accuracy independent of the trait and LD panel analyzed. The present results suggest that genotype imputation could be a cost-effective strategy for genomic selection in Nile tilapia breeding programs.

The effect of pile driving noise on the marine environment is an important factor in environmental impact assessment of planned marine structures, such as ports, bridges or offshore wind farms. Models for predicting the noise levels are essential in order to successfully predict and control the environmental impact of noise produced by such activities in the planning phase. The first COMPILE workshop was organized in 2014 by the Hamburg University of Technology and TNO to allow a cost efficient validation of different numerical models for underwater pile driving noise that have been developed by various institutes around the world. This workshop involved the prediction of relevant acoustic quantities at different ranges and depths for a generic pile-driving set-up, and allowed the results of different models to be compared. Subsequently, the COMPILE II workshop was held in November 2017. The benchmark case for this workshop was set up by TUHH, TNO and E.ON Climate & Renewables and is based on a real-life example, allowing for a model validation based on measurements. The model parameters for the pile and the environmental conditions will be described, and a selection of the outcomes of the workshop will be presented. Copyright © by International Institute of Acoustics & Vibration. All rights reserved.

The effect of pile driving noise on the marine environment is an important factor in environmental impact assessment of planned marine structures, such as ports, bridges or offshore wind farms. Models for predicting the noise levels are essential in order to successfully predict and control the environmental impact of noise produced by such activities in the planning phase. The first COMPILE workshop was organized in 2014 by the Hamburg University of Technology and TNO to allow a cost efficient validation of different numerical models for underwater pile driving noise that have been developed by various institutes around the world. This workshop involved the prediction of relevant acoustic quantities at different ranges and depths for a generic pile-driving set-up, and allowed the results of different models to be compared. Subsequently, the COMPILE II workshop was held in November 2017. The benchmark case for this workshop was set up by TUHH, TNO and E.ON Climate & Renewables and is based on a real-life example, allowing for a model validation based on measurements. The model parameters for the pile and the environmental conditions will be described, and a selection of the outcomes of the workshop will be presented. Copyright © by International Institute of Acoustics & Vibration. All rights reserved.

SPINOL-based phosphoric acids are highly effective chiral hosts for the enantioselective liquid–liquid extraction of 1,2-aminoalcohols. The ee is highly dependent on temperature pH and solvent type., Access to enantiopure compounds on large scale in an environmentally friendly and cost-efficient manner remains one of the greatest challenges in chemistry. Resolution of racemates using enantioselective liquid–liquid extraction has great potential to meet that challenge. However, a relatively feeble understanding of the chemical principles and physical properties behind this technique has hampered the development of hosts possessing sufficient resolving power for their application to large scale processes. Herein we present, employing the previously untested SPINOL based phosphoric acids host family, an in depths study of the parameters affecting the efficiency of the resolution of amino-alcohols in the optic of further understanding the core principles behind ELLE. We have systematically investigated the dependencies of the enantioselection by parameters such as the choice of solvent, the temperature, as well as the pH and bring to light many previously unsuspected and highly intriguing interactions. Furthermore, utilizing these new insights to our advantage, we developed novel, highly efficient, extraction and resolving protocols which provide remarkable levels of enantioselectivity. It was shown that the extraction is catalytic in host by demonstrating transport in a U-tube and finally it was demonstrated how the solvent dependency could be exploited in an unprecedented triphasic resolution system.

In this study, advanced exergoeconomic analysis of solar-biomass hybrid energy systems for the northern part of Cameroon is conducted. Three concentrating solar power (CSP) technologies, parabolic trough collector (PTC), linear Fresnel reflector (LFR) and solar tower (ST), hybridised with biomass-fired (BF) technology are investigated. It is found that exergy destruction from the solar field alone is responsible for the most of the whole exergy destructions (86.3% for PTC-BF, 92.2% for ST-BF and 85.4% for LFR-BF). The results show that LFR-BF hybrid system is the best cost-efficient system while ST-BF hybrid system is the worst cost-efficient system considering initial investment, avoidable-endogenous exergy destruction, cost associated with avoidable-endogenous exergy destruction and total cost required for the optimisation. Copyright © 2020 Inderscience Enterprises Ltd.

The development of Molecor´s technology, which is based on the application of a Molecular Orientation process, has delivered a significant turning point in the pipelines sector. With this technological development, the company has begun to manufacture TOM® PVC-O pipes, the most eco-friendly pipes on the market. The Molecor technology enabled eradicating many of the existing disadvantages of thermoplastic pipes. This technology delivers a clear objective; to provide the water industry with a solution for pipes carrying pressurized water in an environmentally friendly, yet cost efficient manner. This also extends a service life compared to pipeline materials currently in use. The Molecor´s technology has faced numerous barriers due to the high level of competitiveness in the market and the relatively short period since its development. Notwithstanding, the technology is now highly recognized by the market and has spread continuously and gradually over the world to the five continents. We have served many international markets: North America (i.e., Canada), South America (i.e., Colombia and Ecuador), European countries (i.e., Italy and Spain), African countries (i.e., South Africa) and East countries (i.e., India, Kazakhstan, Malaysia and Australia).

Diode-pumping Ti: sapphire lasers promises a new approach to low-cost femtosecond light sources. Thus in recent years much effort has been taken just to overcome the quite low power and low beam qualities of available green diodes to obtain output powers of several hundred milliwatts from a fs-laser. In this work we present an alternative method by deploying frequency-doubled IR diodes with good beam qualities to pump fs-lasers. The revolutionary approach allows choosing any pump wavelengths in the green region and avoids complicated relay optics for the diodes. For the first time we show results of a diode-pumped 10 fs-laser and how a single diode setup can be integrated into a 30 x 30 cm(2) fs-laser system generating sub 20 fs laser pulses with output power towards half a Watt. This technology paves the way for a new class of very compact and cost-efficient fs-lasers for life science and industrial applications.

Modern science requires the ability to evaluate large numbers of results from experiments. Therefore, automated interpretation of experimental results often has a significant influence on the costs of a scientific project. One way to reduce these costs is to use ultra low cost and energy-e_cient hardware for building analysis systems. In this paper two cluster systems which make use of Intel Atom micro-ITX boards and other low cost peripherals are compared. Three real world applications are chosen to proof the concept of the systems and compare them. Additionally, synthetic benchmarks are conducted to put the performance of the applications in perspective. The results of the measurements are discussed and used to evaluate the effectiveness of the systems in terms of performance, power consumption and costs. Finally, based on the conclusions, specific application areas are suggested in which the introduced systems perform well and in which it is better to use clusters with high end server components.

OBJECTIVES: This study compared the cost efficiency of observation and inclinometer assessment of trunk and upper-arm inclination in a population of flight baggage handlers, as an illustration of a general procedure for addressing the trade-off between resource consumption and statistical performance in occupational epidemiology. METHODS: Trunk and upper-arm inclination with respect to the line of gravity were assessed for three days on each of 27 airport baggage handlers using simultaneous inclinometer and video recordings. Labor and equipment costs associated with data collection and processing were tracked throughout. Statistical performance was computed from the variance components within and between workers and bias (with inclinometer assumed to produce “correct” inclination angles). The behavior of the trade-off between cost and efficiency with changed sample size, as well as with changed logistics for data collection and processing, was investigated using simulations. RESULTS: At similar total costs, time spent at trunk and arm inclination angles >60 ° as well as 90^th percentile arm inclination were estimated at higher precision using inclinometers, while median inclination and 90th percentile trunk inclination was determined more precisely using observation. This hierarchy remained when the study was reproduced in another population, while inclinometry was more cost-efficient than observation for all three posture variables in a scenario where data were already collected and only needed to be processed. CONCLUSIONS: When statistical performance was measured only in terms of precision, inclinometers were more cost-efficient than observation for two out of three posture metrics investigated. Since observations were biased, inclinometers consistently outperformed observation when both bias and precision were included in statistical performance. This general model for assessing cost efficiency may be used for designing exposure assessment strategies with considerations not only of statistical but also cost criteria. The empirical data provide a specific basis for planning assessments of working postures in occupational groups.

Date of Conference: 15-15 May 1998 Conference name: : Proceedings of the 1998 IEEE International Conference on Acoustics, Speech and Signal Processing, ICASSP '98 It is possible to obtain either exact realizations or useful approximations of linear systems or matrix-vector products arising in many different applications, by synthesizing them in the form of repeated or multi-channel filtering operations in fractional Fourier domains, resulting in much more efficient implementations with acceptable decreases in accuracy. By varying the number and configuration of filter blocks, which may take the form of arbitrary flow graphs, it is possible to trade off between accuracy and efficiency in the desired manner. The proposed scheme constitutes a systematic way of exploiting the information inherent in the regularity or structure of a given linear system or matrix, even when that structure is not readily apparent.

Cellulose nanofibrils (CNF) are promising bio-based materials for numerous applications, either as replacement of oil-based materials in existing products, potentially with added functionality, or in generating completely new materials and products. CNFs are already commercially available in significant quantities and commercial products based on them have emerged into markets. However, some challenges still remain with the current production technologies of CNFs. Despite rigorous process development, the production costs often remain high and the resulting material is at low consistency. These obstacles may slow down the spreading of the CNF technologies as well as restrict their applicability for certain water-sensitive applications, such as composites, and prevent long-distance transportation, thus leading to limited availability of the material. Recent advances in the production methods attempt to remove the technology-related barriers. For example, high-consistency enzymatic fibrillation (HefCel) technology developed at VTT offers a cost-efficient way to produce fibrillated cellulose materials at high consistency (20-40%). The process is simple, consisting only of few steps and can utilize existing industrial equipment. The produced fibrillated cellulose material is at high consistency and easy to handle. The higher dry matter content makes off-site production and transportation more feasible compared to traditional CNFs. In addition, progress has been made in the drying technologies of CNFs. CNF-related applications are on a different technology readiness level (TRL). Use of CNF in the board making is already on an established level and its use in liquid packaging as barrier materials has been piloted commercially. The rheological properties of CNF suspensions are well known and their potential as stabilizers in food, cosmetics, paints and oil&gas has been studied to some extent. Promising novel high-value applications with lower TRL include membranes for water and air purification, yarns for textile applications, 3D composites, substrates for printed electronics, optical structures and energy storage. New potential applications arise constantly all over the world. In this presentation, an overview on the advances of CNF technologies and applications will be given, with special emphasis on the applicatios that are of most interest to the audience.

In photonic module integration, optoelectronic chips, micro-optical elements and integrated circuits are integrated into functional components, sub-assemblies, modules and systems. The building blocks of the photonicsystem must be fabricated by the use of cost-efficient, reproducible, well-established, high-volume manufacturing technologies. The reliability of the system as well as the tolerances of device alignment are key issue in the integration. We have developed a Low Temperature Co-fired Ceramics (LTCC) toolbox for photonic integration. The primary aim was to process co-fired 3D structures, such as, grooves, cavities, holes, bumps and alignment fiducials for the passive alignment of photonic devices. LTCC provides means for full 3D integration. The tolerances of the alignment structures are typically ±5µm and in some specific cases ±2µm. LTCC structures provide means for the passive alignment of multimode fiber, for example. With Monte-Carlo tolerancing tools, we can simulate and optimize the performance of the system and estimate manufacturing yield in volume production. Thermal management by the use of thermal vias is a well-established technique; liquid cooling channels in the LTCC substrate provide efficient means for high-power laser cooling. LTCC providesinherently hermetic substrate allowing the possibility for hermetic encapsulation. High-speed ICs as well as millimeter-wave circuits can easily be integrated into the LTCC substrate. Novel materials allow the fabrication of advanced systems, especially, for millimeter-wave operation.

Future wireless communication systems are expected to provide more stable and higher data rate transmissions in the whole network. WiMAX is one of the technologies to cover diverse geographic regions. WiMAX covers the high dense urban areas and provide access over large geographic regions in remote rural area. However, in both scenarios it is challenging to cover the entire service area. In both cases relays are foreseen to extend the range of the BS and to increase the system throughput allowing for a cost-efficient deployment and service. As multi-hop/relay has complex interactions between the routing and medium access control decisions, the extent to which analytical expressions can be used to explore its benefits are limited. Consequently simulations tend to be the preferred way of assessing the performance of relays. In this paper, we explain, how to deploy fixed-relay and mobile relay by using computer simulation in WiMAX system and we consistently observed that the throughput is increased and the outage is decreased in the relay-augmented WiMAX network, which is converted to range extension without any capacity penalty, for the realistic range of values of the propagation and other system parameters investigated.