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This paper investigates a scheduling model with certain co-existing features of serial-batching, dynamic job arrival, multi-types of job, and setup time. In this proposed model, the jobs of all types are first partitioned into serial batches, which are then processed on a single serial-batching machine with an independent constant setup time for each new batch. In order to solve this scheduling problem, we divide it into two phases based on job arrival times, and we also derive and prove certain constructive properties for these two phases. Relying on these properties, we develop a two-phase hybrid algorithm (TPHA). In addition, a valid lower bound of the problem is also derived. This is used to validate the quality of the proposed algorithm. Computational experiments, both with small- and large-scale problems, are performed in order to evaluate the performance of TPHA. The computational results indicate that TPHA outperforms seven other heuristic algorithms. For all test problems of different job sizes, the average gap percentage between the makespan, obtained using TPHA, and the lower bound does not exceed 5.41 %.

With increased demands, power modules are often required to run at higher temperatures with improved reliability. Solder joint fatigue is a major failure mode for current power modules. Silver sintering die-attach technology significantly improves power module reliability. Due to the reliability problem at the interface between aluminum (Al) wire and a silver (Ag) layer, bonding Ag wire to the Ag layer is highly desired. Ag wire is harder and stiffer than Al wire, resulting in much higher wear and significantly reduced lifetime of consumables. This paper introduced the K&S CuEx™ bond tool and studied coupling and interaction between the bond tool and Ag wire. By optimizing the bonding process, the CuEx™ bond tools achieved 400,000 touchdowns, which is 80× more than the standard bond tool lifetime of 5,000 touchdowns. The difference between the front-cut and rear-cut process is discussed. By studying and optimizing the cutting process, the standard rear-cut cutter blade lifetime is increased 4×, from 50,000 cuts to 200,000 cuts. It is observed that Ag wire did not wear a wire guide much faster than Al wire. The standard wire guide exhibited minimum wear after 200,000 bonds.

This paper presents a novel control strategy for an above-knee powered prosthetic leg that unifies the entire gait cycle, eliminating the need to switch between controllers during different periods of gait. Current control methods divide the gait cycle into several sequential periods each with independent controllers, resulting in many patient-specific control parameters and switching rules that must be tuned by clinicians. Having a single controller could reduce the number of control parameters to be tuned for each patient, thereby reducing the clinical time and effort involved in fitting a powered prosthesis for a lower-limb amputee. Using the Discrete Fourier Transformation, a single virtual constraint is derived that exactly characterizes the desired actuated joint motion over the entire gait cycle. Because the virtual constraint is defined as a periodic function of a monotonically increasing phase variable, no switching or resetting is necessary within or across gait cycles. The output function is zeroed using feedback linearization to produce a single, unified controller. The method is illustrated with simulations of a powered knee-ankle prosthesis in an amputee biped model and with examples of systematically generated output functions for different walking speeds.

The continuous Skyline query has recently become the subject of the several researches due to its wide spectrum of applications such as multi-criteria decision making, graph analysis network, wireless sensor network and data exploration. In these applications, the datasets are huge and have various dimensions. Moreover, they constantly change as time passes. Therefore, this query is considered as a computation intensive operation that finding the result in a reasonable time is a challenge. In this paper, we present an efficient parallel continuous Skyline approach. In our suggested method, the dataset points are sorted and pruned based on Manhattan distance. Moreover, we use several optimization methods to optimize memory usage in comparison with naive implementation. In addition, besides the applied conventional parallelization methods, we partition the time steps based on the number of available cores. The experimental results for a dataset that contains 800k points with 7 dimensions show considerable speedup.

This paper presents a novel fuzzy adaptive controller for controlling a class of dead-zone output nonlinear systems with time delays. A new approximate model is first designed to describe a special dead-zone phenomenon encountered by the output mechanism of nonlinear systems, and the proposed smooth model can be conveniently fused with available adaptive fuzzy control techniques. In addition, the coupling effect that the dead-zone output and the time-delayed states coexist in a common coupling function makes the tracking control design more complicated. To further address this difficulty, a compensation method using mean-value theorem with Lyapunov–Krasovskii function is presented in this paper. By using the proposed output dead-zone model, and based on Lyapunov synthesis, a new optimized algorithm is developed to guarantee the prescribed convergence of tracking error and the boundedness of all the signals in the closed-loop systems. Simulations have been implemented to verify the performance of the proposed fuzzy adaptive controller.

This paper presents the fabrication, characterization, and testing of the photocatalytic potential of a non-modified titania nanotube (TNT) and Sn-modified TNT synthesized through a facile one-step hydrothermal method. Two tin compounds (SnCl2 and SnO2) and aqueous solutions (HCl and SnCl2) were utilized as precursors and acid washing solutions, respectively. Because the Sn-modified TNT was free of calcination, the resulting sample possessed a high Brunauer-Emmett-Teller surface area. In addition, the Sn-modified TNT exhibited higher electron-hole separation efficiency. The photocatalytic reaction rate for the sample with methylene blue and malachite green dye decomposition was governed on the basis of their pre-adsorption abilities. The Sn-modified TNT had more Cl species than the non-modified TNT, resulting in higher pre-adsorption abilities for the methylene blue dye. Even though the Cl species on SnO2-TNT sample surface were removed, a higher electron-hole separation efficiency and anatase-rutile mixed phase can promote the photocatalyst activity of SnO2-TNT. On the other hand, the Cl species on the surface of SnO2-TNT-HCl washing sample appeared to act as one of the adsorption sites and enhance gaseous elemental mercury removal.

The paper presents the results of a comparative study on accelerated aging of specially designed experimental transformers and their corresponding laboratory models. The experimental transformers are 300 kVA, with insulation in line with medium size and large mineral oil immersed power transformers, having different initial water contents in the standard Kraft paper insulation of ca. 1 and 4 %. These transformers were subjected to the rated current and voltage conditions, operating in the irregular parallel operation, whereby the temperature of windings were measured with fiber optics sensors and kept at 105 °C for 460 days. Each transformer was equipped with a removable tank which allowed access to the outer surface of the HV windings. Laboratory experiments were simulating experimental transformers and were performed in Erlenmeyer flasks, containing oil, paper materials, copper and iron in the same proportions as in the active part of the experimental transformers. The parameters that were monitored during aging were the following: degree of polymerization of paper, hot-spot temperature of transformers, water content in paper, and water and furans content in the oil. Estimations of water content in solid insulation of experimental transformers using frequency domain spectroscopy and the Perrier-Lukic moisture equilibrium chart were performed. The experimental results show that shortening of the insulation life, defined by the value of degree of polymerization, increased 2.5 times with increasing moisture content in the cellulose from ca. 1 to 4 %. For both experimental transformers and laboratory models, the relationships between the paper degree of polymerization and the furans content for dry and wet insulation was developed and is presented in the paper.

Earthworms can alter the soil environment by changing soil properties. They have great potentiality to enhance soil physical properties like bulk density, infiltrability, hydraulic conductivity, porosity, aggregate stability. Due to this ability they are only species which plays significant role in pedoturbation. Similarly, their role in nutrient cycling and organic matter breakdown is of unique interest. Earthworm cast fortified with the microbial population. Increasing microbial activity in soil, increases the nutrient mineralization and release. Earthworm activity enhances root distribution so that immobile macro nutrients like phosphorous and other micronutrients, which are absorbed by plant through root interception, are easily available to the plants. Hence, earthworms play important role in bioturbation, they are considered as 'soil engineer.' However, their activity differs with the agroecosystems. Their population density is more in reduced tillage system than conventional tillage system, aerobic condition than anaerobic conditions, grasslands than forest. Low population of earthworm was found in dry land agroecosystems. But earthworm presence in extreme environment is not studied well yet. So, this paper was reviewed to explore the role of earthworm as soil and ecosystem engineer. This was already established fact but main aim of this paper is to collect the related information and conclude the future research prospects to strengthen the earthworm role as soil and ecosystem engineer.

Solving partial differential equations using neural networks is mostly a proof of concept approach. In the case of direct function approximation, a single neural network is constructed to be the solution of a particular boundary value problem. Independent variables are fed into the input layer, and a single output is considered as the solution’s value. The network is substituted into the equation, and the residual is then minimized with respect to the weights of the network using a gradient-based method. Our previous work showed that by minimizing all derivatives of the residual up to the third order one can obtain a machine precise solution for 2D boundary value problem using very sparse grids. The goal of this paper is to use this grid complexity advantage in order to obtain a solution faster than finite differences. However, the number of all possible high-order derivatives (and therefore the training time) increases with the number of dimensions and it was unclear whether this goal can be achieved. Here, we demonstrate that this increase can be compensated by using random directional derivatives instead. In 2D case neural networks are slower than finite differences, but for each additional dimension the complexity increases approximately 4 times for neural networks and 125 times for finite differences. This allows neural networks to catch up in 3D case for memory complexity and in 5D case for time complexity. For the first time a machine precise solution was obtained with neural network faster than with finite differences method.

A simulation model for water quality in the river Drava is presented in this paper, including the space extent of the model, modelling of physical, chemical and biological processes in the river, as well. Simulation of water quality was performed using the software MIKE 11 (Danish Hydraulic Institute). The main goal of the study was the simulation of the water quality for quasi- steady state in two scenarios of the short-term changes in water quality. We simulated in scenario no. 1 two- day failure of the waste water treatment plant in the agglomeration Belišće, in the second scenario, we simulated the impact of waste water from combined sewer overflows in the Osijek agglomeration. The model was used for modelling of various impacts on the water quality due to the different management practices of pollution point sources

For practical application, optical limiting materials must exhibit a fast response and a low threshold in order to be used for the protection of the human eye and electro-optical sensors against intense light. Many nanomaterials have been found to exhibit optical limiting properties. Laser ablation offers the possibility of fabricating nanoparticles from a wide range of target materials. For practical use of these materials, their optical limiting performance, including optical limiting threshold and the ability to efficiently attenuate high intensity light, needs to be improved. In this paper, we fabricate nanoparticles of different metals by laser ablation in liquid. We study the optical nonlinear properties of the laser-generated nanoparticle dispersion. Silica microspheres are used to enhance the optical limiting performance of the nanoparticle dispersion. The change in the optical nonlinear properties of the laser-generated nanoparticle dispersion caused by silica microspheres is studied. It is found that the incident laser beam is locally focused by the microspheres, leading to an increased optical nonlinearity of the nanoparticle dispersion.

Reviews from players regarding different characteristics of an esports game are one of the worthiest sources for the developers to enhance their services or adjust operating strategy. However, little research has been conducted on detecting esports players’ favorite topics dealing with topic modeling. Thus, this paper aims to use a data mining approach to analyze community data in the games domain available on Steam. We collected more than 1.2 million English reviews from four esports games up to August 2020 on Steam. Our contributions in this paper are: (i) we manually build a dataset by filtering out high-quality esports reviews, (ii) we then infer and group reviews into 3 groups with 19 topics, and (iii) we add more contributions to finding the emerging opinions of esports players towards the different topics of esports reviews, which might benefit further research on understanding esports reviews.

This paper studies the dynamic time-varying formation control of multi-agent systems. Aiming at the unmanned vehicle systems, based on the static time-varying formation in literature [18], a multi-agent dynamic time-varying formation control based on consistency is put forward. Additionally, the sufficient conditions for the agreement and the steps for solving the control parameters are given. The simulation is conducted to prove the effectiveness and robustness of the theoretical results.

This paper presents an integrated simulation approach for studying the circular interpolation regime of CNC laser cutting machines. The circular interpolation algorithm is studied, taking into consideration the numerical character of the system. A simulation diagram, which is able to generate the kinematic inputs for the feed drives of the CNC laser cutting machine is also presented.

This paper proposes a new filtering scheme applied to a linearized model of a nonlinear representation for combustion systems, whose parameters are obtained by means of optical sensors. To ensure a robust representation regarding the chosen operation point and external disturbances variations, a linear parameter-varying (LPV) state-space representation is proposed in terms of noise disturbances and time-varying parameters affecting the plant (like the instrumentation noise and non-laminar air flow). Concerning the proposed filtering scheme, a new observer structure, which includes the incorporation of the control signal as an additional input of the filter, is proposed to assure improved stability margins and performance given in terms of the H

El presente trabajo tiene como objetivo analizar las formas de sociabilidad entre estudiantes secundarios de dos escuelas de gestión estatal de la provincia de Buenos Aires en Argentina. Se trata de una investigación cualitativa cuyo corpus empírico está compuesto por sociogramas, entrevistas en profundidad y grupos focales realizados con alumnos durante los años 2012 y 2014. En un primer momento, se analizan los modos de agrupamiento de los jóvenes en cada una de sus escuelas. Luego, se indagan los motivos por los cuales los estudiantes se eligen o rechazan con sus compañeros. Por último, se interpreta que las diferentes formas de sociabilidad en cada escuela están asociadas al grado de movilidad del plantel estudiantil de cada institución. The aim of this paper is to analyze the forms of sociability among secondary school students in two state-managed schools in the province of Buenos Aires, Argentina. The research was of a qualitative nature, and its empirical corpus consists of sociograms, in-depth interviews, and focus groups carried out with students in 2012 and 2014. First, the types of young people’s groups in each school are analyzed. Then the students’ motives for selecting or rejecting classmates are researched. Lastly, the different forms of sociability in each school are interpreted to be associated with the degree of student mobility in each institution. Fil: Di Napoli, Pablo Nahuel. Universidad de Buenos Aires. Facultad de Filosofia y Letras. Instituto de Investigación en Ciencias de la Educación; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

The history of the computer science department at the Institute of Mathematics and Informatics of Bulgarian Academy of Sciences since 1963 is briefly described. Starting with small groups of enthusiastic people initiating the new for Bulgaria research in the field of Informatics, nowadays the department can report some significant achievements. The paper presents some of them in three areas—software quality evaluation and management, data mining and semantic analysis, information systems and communities—which mark some key areas of research during the years.

Group-based cryptography is viewed as a modern cryptographic candidate solution to blocking quantum computer attacks, and key exchange protocols on the Internet are one of the primitives to ensure the security of communication. In 2016 Habeeb et al proposed a “textbook” key exchange protocol based on the semidirect product of two groups, which is insecure for use in real-world applications. In this paper, after discarding the unnecessary disguising notion of semidirect product in the protocol, we establish a simplified yet enhanced authenticated key agreement scheme based on cyclic automorphism subgroups of random orders by making hybrid use of certificates and symmetric-key encryption as challenge-and-responses in the public-key setting. Its passive security is formally analyzed, which is relative to the cryptographic hardness assumption of a computational number-theoretic problem. Cryptanalysis of this scheme shows that it is secure against the intruder-in-the-middle attack even in the worst case of compromising the signatures, and provides explicit key confirmation to both parties.

A high quality and precise machine and tool component is needed to produce the desire product. In order to manufacture in the shop floor machine factory, it significant to find the best solution with taking into account the tool condition, tool failure, thermal softening and surface finish etc. The purpose of this paper is to investigate the effects of 2 dimensional Ultrasonic Vibration Assisted Milling (UVAM) cutting mechanics, considering tool path trajectory and the effect on the chip thickness. The theoretical modelling of cutting mechanics is focused by considering the trajectory of the tool locus into the workpiece during the machining. The studies found the major advantages of VAM are come from the intermittent tool tip interaction phenomena between cutting tool and workpiece. The reduction of thinning chip thickness formations can be identifying advantages from vibration assisted milling in 2 dimensional. It is discovered that the main increase in cutting force reduction, temperature reduction, increased tool life, discontinuous, thinning, and improvements in chip formation, and improving surface roughness resulted from the effect of the tool entering and disengaging from the workpiece.

The paper re-assesses South Korean unification narratives in the context of territory and critical approaches to territory. From this, the paper identifies a set of underlying assumptions and expec...

Modeling for robotic joints is actually complex and may lead to wrong Pareto-optimal solutions. Hence, this paper develops a new hybrid approach for multiobjective optimization design of a flexure elbow joint. The joint is designed for the upper-limb assistive device for physically disable people. The optimization problem considers three design variables and two objective functions. An efficient hybrid optimization approach of central composite design (CDD), finite element method (FEM), Kigring metamodel, and multiobjective genetic algorithm (MOGA) is developed. The CDD is used to establish the number of numerical experiments. The FEM is developed to retrieve the strain energy and the reaction torque of joint. And then, the Kigring metamodel is used as a black-box to find the pseudoobjective functions. Based on pseudoobjective functions, the MOGA is applied to find the optimal solutions. Traditionally, an evolutionary optimization algorithm can only find one Pareto front. However, the proposed approach can generate 6 Pareto-optimal solutions, as near optimal candidates, which provides a good decision-maker. Based on the user’s real-work problem, one of the best optimal solutions is chosen. The results found that the optimal strain energy is about 0.0033 mJ and the optimal torque is approximately 588.94 Nm. Analysis of variance is performed to identify the significant contribution of design variables. The sensitivity analysis is then carried out to determine the effect degree of each parameter on the responses. The predictions are in a good agreement with validations. It confirms that the proposed hybrid optimization approach has an effectiveness to solve for complex optimization problems.

For a continuous function $f \in \mathcal{C}([0,1])$, define the Vervaat transform $V(f)(t):=f(\tau(f)+t \mod1)+f(1)1_{\{t+\tau(f) \geq 1\}}-f(\tau(f))$, where $\tau(f)$ corresponds to the first time at which the minimum of $f$ is attained. Motivated by recent study of quantile transforms of random walks and Brownian motion, we investigate the Vervaat transform of Brownian motion and Brownian bridges with arbitrary endpoints. When the two endpoints of the bridge are not the same, the Vervaat transform is not Markovian. We describe its distribution by path decomposition and study its semi-martingale property. The same study is done for the Vervaat transform of unconditioned Brownian motion, the expectation and variance of which are also derived., Comment: 31 Pages, 4 figures. This paper (published by http://ejp.ejpecp.org/article/view/3744) is combined of two papers "On Vervaat transform of Brownian bridges and Brownian motion"(arXiv:1307.7952) by Jim Pitman and Wenpin Tang, and "Some points on Vervaat's transform of Brownian bridges and Brownian motion"(arXiv:1308.3759) by Titus Lupu

Purpose Scholars have emphasized intellectual capital’s importance for universities in obtaining competitive advantages and creating value. The purpose of this paper is to identify the influences of two components of intellectual capital, relational and human capital at the international level, and psychological capital on international orientation of academic entrepreneurs, and the mediating effects of international relational and human capital.Design/methodology/approach On the basis of a literature review, a theoretical model is proposed to explain the relationship between the studied variables. Our hypotheses are tested on a sample of 173 academic spin-offs of Spanish universities using bootstrapping methodology.Findings The results show that the international market relational capital and international human capital of academic entrepreneurs influence their international orientation, and that their psychological capital is directly, and indirectly, related to international orientation through international human capital and international market relational capital.Practical implications This study provides a better understanding of the antecedents of the international orientation of academic entrepreneurs, which would provide an important contribution to the literature on intellectual capital, academic entrepreneurship and internationalization. The achieved results highlight important implications for training of academic entrepreneurs and for managers and management teams of companies willing to enter, or even those already operating in, international markets.Originality/value In this study, the international orientation of academic entrepreneurs is explained through the psychological capital that is studied jointly with two components of intellectual capital, relational and human capital at the international level. Although some recent work has focused on the study of the internationalization of academic spin-off, this line of research is still incipient.

Today, around the world, Build-Operate-Transfer (BOT) project finance model is used frequently in numerous projects. One key aspect to the success of project company who wishing to gain BOT tender is to prepare a financial package consistent with the expectations of the related participants in accordance with BOT contract. The debt to equity ratio, the concession length and the unit prices are the important financial decision variables to be determined by the project company. The objective of this paper is to present financial optimization model including two different procurement objectives; (1) potential of winning a BOT project and (2) potential of finding debt. The optimization model solved by multi-objective evolutionary algorithm generate a set of pareto solutions to help project company assess the trade-offs between the two competing objectives. To show application of the model, a real airport YİD project in Turkey study is conducted., Bugün dünyada pek çok projede Yap İşlet Devret (YİD) proje finansman modelinin sıklıkla kullanıldığını gözlemlemekteyiz. YİD ihalesini kazanmak isteyen proje şirketinin başarısı için kilit görüş, YİD sözleşmesi gereğince ilişkide olduğu tarafların beklentileriyle uyumlu finansal bir paket hazırlamasıdır. Proje şirketinin belirleyeceği özsermaye borç oranı, imtiyaz (çalışma) süresi ve ürün/hizmetlerin birim fiyatları önemli finansal karar değişkenleridir. Proje şirketinin ihaleyi kazanma potansiyeli ve borç bulma potansiyeli iki farklı ihale hedefidir. Çalışmanın amacı, bu hedefleri içeren finansal optimizasyon modelini sunmaktır. Çok amaçlı evrimsel algoritma ile çözümlenen model, pareto çözümler kümesi sunarak, iki çelişen amaç arasındaki değişimi değerlendirmede karar vericilere yardımcı olmaktadır. Modelin uygulaması için Türkiye’deki bir havaalanı YİD projesi verileri kullanılmıştır.

Ovaj se rad bavi integracijom fotonaponske elektrane u elektroenergetski sustav. Rad opisuje emisiju viših harmonika u mrežu te njihove utjecaje na pojedine komponente mreže te ukupnu stabilnost i funkcionalnost sustava. Također je u radu opisan i granični udio distribuirane proizvodnje u onosu na potrošača. This paper analyses the integration of photovoltaic systems into the power grid. It describes the emission of higher harmonics into the grid and their influence on each component of the grid as well as stability and functionality of the system. Furthermore, the paper describes the limit of distributed generation in relation to consumer's side of the grid.

Oxygen levels are unequal in different living geographical locations of human and related to normal physiology of health. The reduction of oxygen level in the body can lead to a variety of diseases, such as stroke caused by cerebral ischemia and hypoxia. In the recent years, many studies have elucidated the molecular and cellular mechanisms of organism response to different oxygen concentrations by using the nematode Caenorhabditis elegans (C. elegans) as model organism. C. elegans can escape hypoxia or hyperoxia and adapt to the ambient oxygen environments, and there are different response and regulation mechanisms in different degrees of hypoxia environment. In this paper, recent advances in the reaction of nematodes to different oxygen concentrations and the underlying mechanism were reviewed.

Freshwater wetlands located in dryland environments are characterised by high evapotranspiration rates and frequent periods of desiccation, which strongly influence the water chemistry and solute budgets of these systems. The transpiration of groundwater, especially by trees, is an important mechanism through which dryland wetlands can lose water. This process can lead to groundwater salinization and the precipitation of substantial quantities of mineral phases within the soil, the accumulation of which can have profound consequences for wetland structure and function. This paper aims to bring together current knowledge on the processes that result in solute accumulation and chemical sedimentation which assist in maintaining freshwater conditions in many seasonal dryland wetlands. Examples from central and southern Africa, Australia and South America are presented to illustrate the geomorphically diverse settings under which chemical sedimentation can occur, and the importance of these processes for the resilience and longevity of dryland wetlands. We show that the localised development of saline groundwater and subsurface precipitation of minerals within soils can play a key role in creating and maintaining the habitat diversity of dryland wetlands. Wetland vegetation focuses the accumulation of deleterious constituents, thereby preventing widespread salinization and playa-lake formation, and thus ensuring that the bulk of the surface water remains fresh. Although such processes remain widely understudied, we suggest that chemical sedimentation could be a common phenomenon in many dryland wetlands and have important implications for the future management of these ecosystems.

Local participation is a solution for getting decreased the social relationship that is presented by the recent urbanism paradigms and sustainable development. The main standpoint of this paper was to analyze the citizen's perceptual concepts as a missing link between the physical principles of local center and public participation. The selected perceptual concepts were sociopetal, security and memorabilia. This paper chose one of the regions of "Tehran" as its case study. The methodology of this paper is factor analysis via questionnaire. The paper concluded the perceptual concepts with their similar physical principles that more effectively relate to the participation. Keywords: Public Participation (P.P); Local Centre; Perceptual Concepts (P.C); physical principles. eISSN 2514-7528 © 2018. The Authors. Published for AMER ABRA cE-Bs by e-International Publishing House, Ltd., UK. This is an open-access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). Peer–review under responsibility of AMER (Association of Malaysian Environment-Behaviour Researchers), ABRA (Association of Behavioural Researchers on Asians) and cE-Bs (Centre for Environment-Behaviour Studies), Faculty of Architecture, Planning & Surveying, Universiti Teknologi MARA, Malaysia. DOI: https://doi.org/10.21834/jabs.v3i10.300

Rework in construction projects can cause significant waste of cost and time. Within lean construction practice, rework minimisation is of most interest among project managers. However, less attention has been paid to investigating rework reduction or avoidance in the housing supply chain. Given the increasing costs incurred due to rework generation, innovative approaches to reduce and avoid rework throughout the housing supply chain has never been more urgently required. Elaborating the root causes of rework is essential as it clearly highlights the role of various supply chain contributors. This paper investigates the root causes of rework in construction projects in general and in housing projects in particular. More specifically, the impact of rework on the entire housing supply chain will be explained.

In this paper, we consider the age of information (AoI) of a discrete time status updating system, focusing on finding the stationary AoI distribution assuming that the Ber/G/1/1 queue is used. Following the standard queueing theory, we show that by invoking a two-dimensional state vector which tracks the AoI and packet age in system simultaneously, the stationary AoI distribution can be derived by analyzing the steady state of the constituted two-dimensional stochastic process. We give the general formula of the AoI distribution and calculate the explicit expression when the service time is also geometrically distributed. The discrete and continuous AoI are compared, we depict the mean of discrete AoI and that of continuous time AoI for system with M/M/1/1 queue. Although the stationary AoI distribution of some continuous time single-server system has been determined before, in this paper, we shall prove that the standard queueing theory is still appliable to analyze the discrete AoI, which is even stronger than the proposed methods handling the continuous AoI., 9 pages, 3 figures, Accepted for presentation in ITW 2021

Background The health system in South Sudan faces extreme domestic resource constraints, low capacity, and protracted humanitarian crises. Supportive supervision is believed to improve the quality of health care and service delivery by compensating for flaws in health workforce management. This study aimed to explore the current supervision practices in South Sudan and identify areas for quality improvement. Methods The study employed qualitative approaches to collect and analyse data from six purposefully selected counties. Data were collected from 194 participants using semi-structured interviews (43 health managers) and focus group discussions (151 health workers). Thematic content analysis was used to yield an in-depth understanding of the supervision practices in the health sector. Results The study found that integrated supportive supervision and monitoring visits were the main approaches used for health services supervision in South Sudan. Supportive supervision focused more on health system administration and less on clinical matters. Although fragmented, supportive supervision was carried out quarterly, while monitoring visits were either conducted monthly or ad hoc. Prioritization for supportive supervision was mainly data driven. Paper-based checklists were the most commonly used supervision tools. Many supervisors had no formal training on supportive supervision and only learned on the job. The health workers received on-site verbal feedback and, most times, on-the-job training sessions through coaching and mentorship. Action plans developed during supervision were inadequately followed up due to insufficient funding. Insecurity, poor road networks, lack of competent health managers, poor coordination, and lack of adequate means of transport were some of the challenges experienced during supervision. The presumed outcomes of supportive supervision were improvements in human resource management, drug management, health data reporting, teamwork, and staff respect for one another. Conclusion Supportive supervision remains a daunting task in the South Sudan health sector due to a combination of external and health system factors. Our study findings suggest that strengthening the processes and providing inputs for supervision should be prioritized if quality improvement is to be attained. This necessitates stronger stewardship from the Ministry of Health, integration of different supervision practices, investment in the capacity of the health workforce, and health infrastructure development.

In this paper we present the results of industrial experiments consisted in determination, by specialized measurements, of the dust percentage in the evacuated gases from the EAF and of chemical composition of polluting burnt gases. The electric arc furnaces (EAFs), as powerful energy consumers, are also polluting emissions generators with an important environmental impact. The steel refining in the EAF is based on a complex mechanism of oxidizing chemical processes, due to the introduced oxygen and air. A first step is the diffusion and adsorption on the slag surface of molecular oxygen. The most significant polluting emissions of the EAF are metallic and oxides powders driven by emergent gases.

This paper addresses the Joint Angle and Delay estimation problem of a received multi-carrier frame through multiple antennas. In particular, each source is parameterized through its complex gain, Time-of-arrival (ToA) and Angle-of-arrival (AoA). We develop three novel JADE methods in a partially relaxed model, where one relaxes the interference zone, while focusing on a certain direction at a given time. Computer simulations are given with comparison to the Cramer-Rao Bound.

This paper reported synergistic bimetallic AuCu/TiO2 catalysts for selective oxidation of 1,2-propanediol to lactic acid under very mild conditions (T 92%). Surface characterization reveals that while AuCu forms alloy structure with larger particle size based on TEM images, strong interaction between Au and Cu species is critical for performance enhancement. According to experimental studies on the influence of 1,2-propanediol and NaOH concentration on reaction rates, it is highly possible that 1,2-propanediol is reacted following single-site Langmuir–Hinshelwood mechanism while NaOH acts as a promoter and may block surface sites under relatively higher concentration.

Occupational health and safety regulations are in place to ensure safety standards and improve safety on the worksite. The impact of safety standards varies across industries and certainly impacted by industry specific risk factors, and exogenous factors in the economy that impact the level and change in employment. The purpose of this paper is to use a decomposition approach based on the Tornqvist index to compare and measure the aggregate impact of occupational health and safety regulations, as well as, industry specific risk variables and general economic conditions on lost-time claims for eight industrial sectors in the province of Alberta, Canada. The index approach has the advantage over standard correlation techniques in that the residual value remaining after index decomposition can be defined as the basic industry risk factor for accident and injury.

This paper considers the interplay of international law, politics and national law in the protection of human rights defenders (HRDs) that are challenging businesses practices in Brazil. It argues that the Brazilian State and transnational and domestic businesses have a responsibility to protect HRDs and should adopt robust means of doing this, embracing their work as opportunity rather than a threat in building up a democratic society. To demonstrate the validity of this claim, this paper highlights the role of HRDs in promoting corporate responsibility and in exposing and remedying the adverse human rights (HR) impacts of business in Brazil. It further explains how HRDs working on issues of corporate responsibility and accountability are under threats and attacks from both state and non-state actors as a result of their work. The paper then analyses some of the responses from the organized civil society, business, and the Brazilian State in order to tackle violence against HRDs. The paper considers that the relationship between business and the Brazilian State is dialectical and complementary and, as such, should be arbitrated by the international HR system. In this process, the paper calls for a binding instrument to regulate the activities of transnational corporations and other business enterprises to be adopted at the UN level and argues that it could potentially influence the rhetoric and practices in the politics of HR in Brazil. The final section provides an explanation for how the Brazilian State and transnational and national businesses should protect HRDs. Keywords: Business. Human Rights. Human Rights Defenders.

To improve the intelligent image recognition abilities of edge devices, a parallel-optimization-based framework called POWER is introduced in this paper. With FPGA (Field-Programmable Gate Array) as its hardware module, POWER provides well extensibility and flexible customization capability for developing intelligent firmware suitable for different types of edge devices in various scenarios. Through an actual case study, we design and implement a firmware prototype following the specification of POWER and explore its performance improvement using parallel optimization. Our experimental results show that the firmware prototype we implement exhibits good performance and is applicable to substation inspection robots, which also validate the effectiveness of our POWER framework in designing edge intelligent firmware modules indirectly.

Checking the semantic equivalence of operations is an important task in software development. For instance, regression testing is a routine task when software systems are developed and improved, and software package managers require the equivalence of operations in different versions of a package within the same major version. In order to support a good automation of this process, a solid foundation is required. It has been shown that the notion of equivalence is not obvious when non-deterministic features are present. In this paper, we discuss a general notion of equivalence in functional logic programs and develop a practical method to check it. Our method can be integrated in a property-based testing tool which is used in a software package manager to check the semantic versioning of software packages.

The process of selective laser melting (SLM) is complex and instantaneous, which communicates with a variety of physical phenomena such as solid–liquid phase transition. The microstructure and material properties are favorable evidence to explain the SLM forming mechanism. In this paper, the forming properties of the iron-based alloy, titanium-based alloys, and aluminum-based alloys are discussed, which are relatively mature in research. The influence of processing strategy on the density and quality of metal specimens is briefly introduced. The research progress of microstructure and mechanical properties of metal specimens formed by SLM is mainly introduced. Also, the influence of processing parameters and heat treatment on the microstructure and the effect of microstructure on mechanical properties are summarized. The corrosion behavior of metal specimens formed by SLM is analyzed. Furthermore, the research development of copper-based alloys, shape memory alloys, and high-entropy alloys is presented. Finally, the problems encountered in the alloys forming process are described, and the future development direction has prospected.

White LED lamp are gaining a lot of popularity both on the residential and street lighting markets. Those devices are advertised with a very long lifetime compared to conventional incandescent lamps. A measurement campaign including accelerated ageing and stress test is ongoing in Sweden; parts of the data are joined to data obtained in France. The aim of this paper is to report and analyze which factors can be correlated to LED performance changes. A few commercial lamps were bought anonymously in retail stores; each type comprised 12 samples. A first group undergo long-term lumen maintenance test; the second was stressed by frequent switching (50 000 cycles, 30 seconds on/30 second off); the third and the fourth by frequent cycling (3 000 cycles, 30 minutes on/30 minutes off) at 25 °C and 75°C respectively. The assesment are made based on the change of the lumen, lamp efficiency, Correlated Color Temperature and Color Rendering index of the produced light before and after the test.

[ES] Los sistemas de refrigeración por eyección activados por calor de origen renovable o fuentes de calor residual tienen el potencial de alcanzar ahorros energéticos significativos al sustituir o asistir a los sistemas de refrigeración tradicionales. Su campo de aplicabilidad es muy amplio y el presente trabajo se ha centrado en un estudio detallado de dos aplicaciones con gran potencial siguiendo un enfoque computacional: (i) generación de aire acondicionado activado por energía solar térmica y (ii) refrigeración de la admisión de un motor de combustión reutilizando la energía térmica disponible en la línea de escape de este. Las actividades de investigación han estado dirigidas a mitigar dos de los principales puntos débiles que caracterizan a los ciclos de refrigeración por eyección: su eficiencia relativamente baja y la incapacidad mostrada por la configuración base del ciclo de eyección para operar de forma robusta en condiciones de operación alejadas de las de diseño. La primera cuestión ha sido abordada principalmente diseñando geometrías de eyector altamente optimizadas usando técnicas de mecánica de fluidos computacional y optimizando la integración del eyector en el conjunto del sistema de refrigeración. La segunda cuestión se ha abordado caracterizando el comportamiento del sistema en condiciones de diseño y fuera de diseño. Se han propuesto dos estrategias avanzadas para hacer frente a la caída de prestaciones que sufre el sistema al operar en condiciones fuera de diseño, como son la utilización de eyectores de geometría ajustable o la implementación de tanques de almacenamiento térmico. La respuesta del sistema se ha analizado en condiciones fuera de diseño con dos aproximaciones temporales complementarias. Los modelos estacionarios se han usado para optimizar las diferentes arquitecturas de eyector y la operación global del sistema en ciertas condiciones de operación representativas, mientras que el análisis transitorio representa un enfoque más realista y tiene en cuenta la naturaleza impredecible e inestable de la climatología. El estudio se ha concluido con un análisis termoeconómico, el cual ha sido útil para discernir si los diseños altamente optimizados son competitivos al ser comparados con las soluciones de refrigeración que se encuentran actualmente consolidadas en el mercado. La principal conclusión del análisis en condiciones estáticas para la aplicación termosolar es que la transformación de potencia térmica a potencia de refrigeración puede alcanzar un rendimiento del 37.7%, mientras que el rendimiento global del sistema alcanza el 20.1% con diseños altamente optimizados de eyector para unas condiciones de evaporación y condensación de 13°C y 40°C, respectivamente. En condiciones dinámicas, la implementación de la geometría variable mejora en torno a un 40% el rendimiento del sistema de refrigeración, además de incrementar su operatividad. El tanque de almacenamiento térmico juega un papel relevante en este aspecto y, para una envergadura de colector parabólico de 7.1 m, un consumo nominal de 13.3 kW de potencia térmica del tanque ha resultado ser una solución de compromiso para mantener en equilibrio los principales indicadores de prestaciones. El análisis termoeconómico de la arquitectura más prometedora sugiere que el ahorro de coste operativo está lejos de poder compensar la elevada inversión inicial en equipamiento (16.905€ para una capacidad de refrigeración aproximada de 5.6 kW), destacando la dificultad del sistema para competir con las soluciones de refrigeración actualmente consolidadas en el mercado y resaltando la necesidad de considerar soluciones híbridas. La principal conclusión de la aplicación en motor de combustión es que la reducción de temperaturas en la línea de admisión por debajo de 4°C es factible, produciendo mejoras en el rendimiento volumétrico de en torno al 11%, no obstante, el sistema muestra vulnerabilidades al operar en puntos de motor diferentes al de diseño., [CA] Els sistemes de refrigeració per ejecció activats per calor d'origen renovable o fonts de calor residual tenen el potencial d'assolir estalvis energètics significatius al substituir o assistir als sistemes de refrigeració tradicionals. El seu camp d'aplicabilitat es ampli i el present treball s'ha centrat en un estudi detallat de dos aplicacions amb gran potencial seguint un enfocament computacional: (i) generació d'aire condicionat activat per energia solar tèrmica i (ii) refrigeració de l'admissió d'un motor de combustió reutilitzant l'energia tèrmica disponible en la línia d'escapament d'aquest. Les activitats d'investigació han estat dirigides a mitigar dos dels principals punts dèbils que caracteritzen als cicles de refrigeració per ejecció: la seua eficiència relativament baixa i la incapacitat mostrada per la configuració base del cicle d'ejecció per a operar de forma robusta en condicions d'operació allunyades de les de disseny. La primera qüestió ha sigut abordada principalment dissenyant geometries d'ejector altament optimitzades usant tècniques de mecànica de fluids computacional i optimitzant la integració de l'ejector en el conjunt del sistema de refrigeració. La segona qüestió s'ha abordat caracteritzant el comportament del sistema en condicions de disseny i fora de disseny. S'han proposat dos estratègies avançades per a fer front a la caiguda de prestacions que pateix el sistema quan opera en condicions fora de disseny, com són la utilització d'ejectors de geometria ajustable o la implementació de tancs de emmagatzemament tèrmic. La resposta del sistema s'ha analitzat en condicions fora de disseny amb dos aproximacions temporals complementàries. Els models estacionaris s'han usat per a optimitzar les diferents arquitectures d'ejector i l'operació global del sistema en certes condicions d'operació representatives, mentre que l'anàlisi transitori representa un enfocament més realista i té en compte la natura impredictible i inestable dels canvis en les condiciones climàtiques. L'estudi s'ha conclòs amb un anàlisi termoeconòmic, el qual ha sigut útil per a discernir si els dissenys altament optimitzats són competitius quan es comparen amb les solucions de refrigeració que es troben actualment consolidades al mercat. La principal conclusió de l'anàlisi en condicions estàtiques per a l'aplicació termosolar és que la transformació de potència tèrmica a potència de refrigeració pot arribar a un rendiment del 37.7%, mentre que el rendiment global del sistema arriba al 20.1 % amb dissenys altament optimitzats d'ejector per a unes condicions d'evaporació i condensació de 13°C i 40°C, respectivament. En condicions dinàmiques, la implementació de la geometria variable millora al voltant d'un 40% el rendiment del sistema de refrigeració, a més d'incrementar la seua capacitat de romandre en funcionament. El tanc d'emmagatzemament tèrmic juga un paper rellevant en aquest aspecte i, per a una llargària de col·lector parabòlic de 7.1 m, un consum nominal de 13.3 kW de potencia tèrmica del tanc ha resultat ser una solució de compromís per a mantenir en equilibri els principals indicadors de prestacions. L'anàlisi termoeconòmic de l'arquitectura més prometedora suggereix que l'estalvi de cost operatiu està lluny de poder compensar l'elevada inversió inicial en equipament (16.905€ per a una capacitat de refrigeració aproximada de 5.6 kW), posant de manifest la dificultat del sistema per a competir amb les solucions de refrigeració actualment consolidades al mercat i ressaltant la necessitat de considerar solucions híbrides. La principal conclusió de l'aplicació en motor de combustió és que la reducció de temperatures a la línia d'admissió per baix de 4°C és factible, produint millores en el rendiment volumètric de al voltant de l'11%, no obstant això, el sistema mostra vulnerabilitats a l'hora d'operar en punts de motor diferents al de disseny., [EN] Jet-ejector refrigeration systems powered by renewable heat or waste heat sources have the potential to achieve significant primary energy savings when substituting or aiding traditional refrigeration systems. Their field of applicability is vast and the present work has been focused on a detailed study of two applications with great potential following a computational approach: (i) air-conditioning generation powered by solar thermal energy and (ii) internal combustion engine intake air refrigeration powered by its exhaust line waste heat. The research efforts have been directed towards mitigating the negative effect of two of the main weak points of jet-ejector refrigeration systems: their relatively low efficiency and the incapacity of the baseline configuration to operate robustly away from the design conditions. The first issue has been addressed mainly by designing highly optimized jet-ejector geometries using computational fluid dynamics techniques and optimizing the jet-ejector integration in the overall system. The second one has been addressed by carrying out complete characterizations of the refrigeration system response in design and off-design conditions. Advanced strategies to face the refrigeration system performance decay away from design conditions have been proposed, like the utilization of adjustable jet-ejector architectures or the implementation of hot thermal storage tanks. The system response has been analyzed in off-design conditions with two complementary temporal schemes. The steady-state models have been used to optimize the jet-ejector architectures and the overall system operation for representative operating scenarios, while the transient analysis represents a more realistic approach and accounts for changes in climatic conditions, which have an unpredictable and unstable nature. The study has been concluded with a thermoeconomic analysis, which has been useful to discern if the highly optimized designs are competitive when compared to existing refrigeration solutions consolidated in the market. The main conclusions of the steady-state analysis for the solar application are that the transformation from thermal power to refrigeration power can achieve an efficiency of 37.7%, while the global efficiency achieves 20.1% when highly optimized jet-ejectors are used for an evaporating and condensing conditions of 13°C and 40°C, respectively. In dynamic conditions, the implantation of an adjustable jet-ejector brings improvements in refrigeration system efficiency of around 40%, besides improving its capacity to remain in operation. The thermal storage system plays a relevant role in this sense and, for a fixed parabolic trough collector span of 7.1 m, a nominal thermal power consumption of 13.3 kW represents a trade-off between the performance indicators subject to analysis. The thermoeconomic assessment of the most promising system architecture suggests that the operating cost savings are far from compensating for the capital expenditures (16,905€ for a refrigeration capacity of approximately 5.6 kW), evidencing the difficulties of the system to compete against refrigeration solutions currently consolidated in the market and outlining the interest in hybrid solutions. The main conclusion of the automotive application is that it is feasible to achieve in the engine intake line temperatures below 4°C, bringing improvements in volumetric engine efficiency of around 11%. Nevertheless, the system shows vulnerabilities when operating in engine operating points different from the design one., My most sincere acknowledgment to the whole CMT-Motores Térmicos team for giving me the opportunity of being part of it and the grant program Subvenciones para la contrataci ́on de personal investigador predoctoral for doctoral studies (reference ACIF/2018/124), awarded by Generalitat Valenciana, Conselleria de Innovación, Universidades, Ciencia y Sociedad Digital and the European Union for funding this project.

Techniques of producing new combinatorial structures from old ones are commonly called trades. The switching principle applies for a broad class of designs: it is a local transformation that modifies two columns of the incidence matrix. In this paper, we present a construction, which is a generalization of the switching transform for the class of Steiner 2-designs. We call this construction paramodification of Steiner 2-designs, since it modifies the parallelism of a subsystem. We study in more detail the paramodifications of affine planes, Steiner triple systems, and abstract unitals. Computational results show that paramodification can construct many new unitals., Revised version based on remarks of anonymous referee

The aim of this article is to form a conceptual framework for analyzing and understanding the latest intermedial practice within the field of new technologies. In order to achieve this, it suggests two converging theoretical strategies. Firstly, the introduction emphasizes on concept of “excommunication,” coined by Alexander R. Galloway in his 2013 book, in order to provide a better understanding of the scenic mediation that encompasses a great number of contemporary productions. More specifically, by both following and criticizing Galloway’s stance on three different media modalities, a fourth mediation vector will be isolated - The Water Principle - incorporated in the mythology of Neptune. Such a theoretical orientation is primarily guided by an ambition to associate intermedial theory with watery elements that appear in two different stage examples analyzed within this paper. Secondly, two different performances will be analyzed: Romeo Castellucci’s “M#10 Marseille” (2002) and “Fontaine Boréale” (2018). Prompted by intermedial issues, these two productions question the ontological claims of the human presence on stage by establishing digital stage simulation as a para-performative phenomenon. By analyzing these plays, I will demonstrate that in both examples, the Water Principle delivers a privileged media model through which aesthetic force is achieved. Finally, on a broader level, the paper suggests that the artistic trajectory of these productions calls for a new perspective on the nature of performance; a perspective emphasizing an aesthetics of disappearance and nonhuman structural impact.

Aluminum/air microfluidic fuel cell (MFC) combines the advantages of co-laminar MFC and aluminum/air batteries with high energy density, low cost, membraneless and miniaturized design, which is a promising device to power the numerous nodes in the Internet of Things (IoT) ecosystems. Here, we propose a recirculating dual-electrolyte aluminum/air MFC with an alkaline anolyte and an acid catholyte. The cell exhibits an outstanding performance with an open-circuit voltage of 2.2 V and a short-current density of 1 A cm−2, benefiting from the dual-electrolyte design. In order to prevent the naturalization reaction between the electrolytes and improve the utilization rate, a regular hierarchical porous carbon paper is applied as the separator, which minimizes the mixing of electrolytes and facilitates the recirculation. This work provides an alternative route for cost-effective and high-performance aluminum/Air MFCs toward real applications.

In this paper a novel algorithm with delay guarantees for high priority traffic based on a Proportional (P) controller for Long-Reach Passive Optical Networks (LR-PONs) is proposed. We have recently demonstrated that Proportional-Integral-Derivative (PID) controllers are quite effective when controlling guaranteed bandwidth levels and in this paper this functionality is adapted to jointly deal with Class of Service (CoS) and client differentiation in order to fulfill delay requirements. Therefore, it leads to an efficient control of the mean packet delay which enhances the provided Quality of Service (QoS) inside the LR-PON. Simulation results have exhibited that the bandwidth allocation process made by the P controller achieves this objective faster than other existing proposals. In fact, it stabilizes the priority delays in less than 2min comparing with 5 or 6min obtained by other proposals. Furthermore, it has been demonstrated that its performance is more robust than other proposals since it is independent of the initial network conditions, adapting very efficiently the available resources in order to comply with the established delay bounds of the most restrictive services.

Adaptive consensus seeking in group decision making.Mutual influence modeling.Taking into account human attitude.Multi-criteria problem using bipolarity concept.Consensus processes with or not individual changes. This paper addresses the collaborative group decision making problems considering a consensus processes to achieve a common legitimate solution. The proposed resolution model is based on individual bipolar assessment. Each decision maker evaluates alternatives through selectability and rejectability measures which respectively represent the positive and negative aspects of alternatives considering objectives achievement. The impact of human behavior (influence, individualism, fear, caution, etc.) on decisional capacity has been taken into account. The influence degrees exerted mutually by decision makers are modeled through concordance and discordance measures. The individualistic nature of decision makers has been taken into account from the individualism degree. In order to achieve a common solution(s), models of consensus building are proposed based on the satisficing game theory formalism for collective decision problems. An application example is given to illustrate the proposed concepts.

As a result of their cell structures, elastomeric foams exhibit high compressibility and are frequently used as buffer cushions in energy absorption. Foam pads between two surfaces typically withstand uniaxial loads. In this paper, we considered the effects of porosity and cell size on the mechanical behavior of random elastomeric foams, and proposed a constitutive model based on an artificial neural network (ANN). Uniform cell size distribution was used to represent monodisperse foam. The constitutive relationship between Cauchy stress and the four input variables of axial stretch λU, lateral stretch λL, porosity φ, and cell size θ was given by con-ANN. The mechanical responses of 500 different foam structures (20% < φ < 60%, 0.1 mm < θ < 0.5 mm) under compression and tension loads (0.4 < λU < 3) were simulated, and a dataset containing 100,000 samples was constructed. We also introduced a pre-ANN to predict lateral stretch to address the issue of missing lateral strain data in practical applications. By combining physical experience, we chose appropriate input forms and activation functions to improve ANN’s extrapolation capability. The results showed that pre-ANN and con-ANN could provide reasonable predictions for λU outside the dataset. We can obtain accurate lateral stretch and axial stress predictions from two ANNs. The porosity affects the stress and λL, while the cell size only affects the stress during foam compression.

Spirulina platensis was cultivated in a vertically aligned photobioreactor for biodiesel synthesis. The algal culture was harvested by centrifugation, and the biomass was dried in an oven. The oil ...

This paper reports on the catalytic performance and deactivation in aqueous phase reforming of wastewater streams for H2 production. Brewery wastewater was chosen as representative of this type of effluent. The effect of catalyst support textural characteristics was evaluated using an activated carbon and different modified supports obtained by infiltration and carbonization of a phenolic resol resin into activated carbon. The effect of active phase was evaluated using Pt and PtRe catalysts with different metal molar ratio. At short time on stream values, Pt catalysts supported on modified activated carbon showed higher H2 production than those supported on unmodified activated carbon, indicating that a lower microporosity facilitates the transport of reactants to catalytic active sites and release of reaction products. Bimetallic PtRe catalysts showed higher activity than Pt, particularly using a metal molar ratio of 1:1, which yielded the highest H2 production (117.2 μmol min−1). Despite the different catalysts tested, early and significant deactivation was observed. The characterization of used catalysts allows postulating the adsorption of organic species and/or coke-like matter deposition on the catalysts surface as main causes of deactivation.

In the paper a concept of creating a filtering network based on first order nonstationary elements is presented. In each element of the structure two outputs were used: low-pass and high-pass. Replacing gain coefficient k and time constant T with gain function and time function considerably improved the system operation in the time domain. During the research effects of the corresponding stationary, nonstationary and partially stationary structures were compared.