Abstract: In recent years, new techniques for solving complex
problems in engineering are proposed. One of these techniques is
JPSO algorithm. With innovative changes in the nature of the jump
algorithm JPSO, it is possible to construct a graph-based solution
with a new algorithm called G-JPSO. In this paper, a new algorithm
to solve the optimal control problem Fletcher-Powell and optimal
control of pumps in water distribution network was evaluated.
Optimal control of pumps comprise of optimum timetable operation
(status on and off) for each of the pumps at the desired time interval.
Maximum number of status on and off for each pumps imposed to the
objective function as another constraint. To determine the optimal
operation of pumps, a model-based optimization-simulation
algorithm was developed based on G-JPSO and JPSO algorithms.
The proposed algorithm results were compared well with the ant
colony algorithm, genetic and JPSO results. This shows the
robustness of proposed algorithm in finding near optimum solutions
with reasonable computational cost.
Abstract: Operation enhancement in an air cooler depends on
rate of heat transfer, and pressure drop. In this paper for a given heat
duty, study of the effects of FPI (Fin Per Inch) and fin type (circular
and hexagonal fins) on heat transfer, and pressure drop in an air
cooler in Iran, Arvand petrochemical. A program in EES
(Engineering Equations Solver) software moreover, Aspen B-JAC
and HTFS+ softwares are used for this purpose to solve governing
equations. At first the simulated results obtained from this program is
compared to the experimental data for two cases of FPI. The effects
of FPI from 3 to 15 over heat transfer (Q) to pressure drop ratio
(Q/Δp ratio). This ratio is one of the main parameters in design, and
simulation heat exchangers. The results show that heat transfer (Q)
and pressure drop increase with increasing FPI steadily, and the Q/Δp
ratio increases to FPI=12 and then decreased gradually to FPI=15,
and Q/Δp ratio is maximum at FPI=12. The FPI value selection
between 8 and 12 obtained as a result to optimum heat transfer to
pressure drop ratio. Also by contrast, between circular and hexagonal
fins results, the Q/Δp ratio of hexagonal fins more than Q/Δp ratio of
circular fins for FPI between 8 and 12 (optimum FPI)
Abstract: Urban areas, as they have been developed and operate
today, are areas of accumulation of a significant amount of people
and a large number of activities that generate desires and reasons for
traveling. The territorial expansion of the cities as well as the need to
preserve the importance of the central city areas lead to the
continuous increase of transportation needs which in the limited
urban space results in creating serious traffic and operational
problems. The modern perception of urban planning is directed towards more
holistic approaches and integrated policies that make it economically
competitive, socially just and more environmentally friendly. Over
the last 25 years, the goal of sustainable transport development has
been central to the agenda of any plan or policy for the city. The
modern planning of urban space takes into account the economic and
social aspects of the city and the importance of the environment to
sustainable urban development. In this context, the European Union
promotes direct or indirect related interventions according to the
cohesion and environmental policies; many countries even had the
chance to actually test them. This paper explores the methods and processes that have been
developed towards this direction and presents a review and
systematic presentation of this work. The ultimate purpose of this
research is to effectively use this review to create a decision making
methodological framework which can be the basis of a useful
operational tool for sustainable urban planning.
Abstract: Home Energy Management System (HEMS), which makes the residential consumers, contribute to the demand response is attracting attention in recent years. An aim of HEMS is to minimize their electricity cost by controlling the use of their appliances according to electricity price. The use of appliances in HEMS may be affected by some conditions such as external temperature and electricity price. Therefore, the user’s usage pattern of appliances should be modeled according to the external conditions, and the resultant usage pattern is related to the user’s comfortability on use of each appliances. This paper proposes a methodology to model the usage pattern based on the historical data with the copula function. Through copula function, the usage range of each appliance can be obtained and is able to satisfy the appropriate user’s comfort according to the external conditions for next day. Within the usage range, an optimal scheduling for appliances would be conducted so as to minimize an electricity cost with considering user’s comfort. Among the home appliance, electric heater (EH) is a representative appliance, which is affected by the external temperature. In this paper, an optimal scheduling algorithm for an electric heater (EH) is addressed based on the method of branch and bound. As a result, scenarios for the EH usage are obtained according to user’s comfort levels and then the residential consumer would select the best scenario. The case study shows the effects of the proposed algorithm compared with the traditional operation of the EH, and it represents impacts of the comfort level on the scheduling result.
Abstract: The Portuguese footwear industry had in the last five years a remarkable performance in the exportation values, the trade balance and others economic indicators. After a long period of difficulties and with a strong reduction of companies and employees since 1994 until 2009, the Portuguese footwear industry changed the strategy and is now a success case between the international players of footwear. Only the Italian industry sells footwear with a higher value than the Portuguese and the distance between them is decreasing year by year. This paper analyses how the Portuguese footwear companies innovate and make innovation, according the classification proposed by the Oslo Manual. Also, analyses the strategy follow in the innovation process and shows the linkage between the type of innovation and the strategy of innovation. The research methodology was qualitative and the strategy for data collection was the case study. The qualitative data will be analyzed with the MAXQDA software. The economic results of the footwear companies studied shows differences between all of them and these differences are related with the innovation strategy adopted. The companies focused in product and marketing innovation, oriented to their target market, have higher ratios “turnover per worker” than the companies focused in process innovation. However, all the footwear companies in this “low-tech” industry create value and contribute to a positive foreign trade of 1.310 million euros in 2013. The growth strategies implemented has the participation of the sectorial organizations in several innovative projects. And it’s obvious that cooperation between all of them is a critical element to the performance achieved by the companies and the innovation observed. The Portuguese footwear sector has in the last years an excellent performance (economic results, exportation values, trade balance, brands and international image) and his performance is strongly related with the strategy in innovation followed, the type of innovation and the networks in the cluster. A simplified model, called “Ace of Diamonds”, is proposed by the authors and explains the way how this performance was reached by the seven companies that participate in the study (two of them are the leaders in the setor), and if this model can be used in others traditional and “low-tech” industries.
Abstract: Effect of alloying on the microstructure and mechanical properties of heat-resisting duplex stainless steel (DSS) for Mg production was investigated in this study. 25Cr-8Ni based DSS’s were cast into rectangular ingots of which the dimension was 350×350×100 mm3 . Nitrogen and Yttrium were added in the range within 0.3 in weight percent. Phase equilibrium was calculated using the FactSage®, thermodynamic software. Hot exposure, high temperature tensile and compression tests were conducted on the ingots at 1230oC, which is operation temperature employed for Mg production by Silico-thermic reduction. The steel with N and Y showed much higher strength than 310S alloy in both tensile and compression tests. By thermal exposition at 1230oC for 200 hrs, hardness of DSS containing N and Y was found to increase. Hot workability of the heat-resisting DSS was evaluated by employing hot rolling at 1230 oC. Hot shortness was observed in the ingot with N and found to disappear after addition of Y.
Abstract: A repairable mechanical system (as agricultural
tractor) is subject to deterioration or repeated failure and needs a
repair shops and also operator’s capability for the repair and
maintenance operations. Data are based on field visits and interviews
with 48MF 285 tractor operators from 14 villages collected in north
of Khouzestan province. The results showed that most operators were
lack the technical skill to service and repair tractors due to
insufficient training, specific education and work experience.
Inadequate repair and maintenance facilities, such as workshops,
mechanics and spare parts depots cause delays in repair work in the
survey areas. Farmers do not keep accurate service records and most
of them disregard proper maintenance and service of their tractors,
such as changing engine oil without following the manufacturer’s
recommendations. Since, Repair and maintenance facilities should be
established in village areas to guarantee timely repair in case of
breakdowns and to make spare parts available at low price. The
operators should keep service records accurately and adhere to
maintenance and service schedules according to the manufacturer’s
instructions. They should also be encouraged to do the service and
maintain their tractors properly.
Abstract: In this paper we present the design of an optical
device based on a Herriott multi-pass cell fabricated on a small sized
acrylic slab for heat flux measurements using the deflection of a laser
beam propagating inside the cell. The beam deflection is produced by
the heat flux conducted to the acrylic slab due to a gradient in the
refractive index. The use of a long path cell as the sensitive element
in this measurement device, gives the possibility of high sensitivity
within a small size device. We present the optical design as well as
some experimental results in order to validate the device’s operation
principle.
Abstract: Carefully scheduling the operations of pumps can be
resulted to significant energy savings. Schedules can be defined
either implicit, in terms of other elements of the network such as tank
levels, or explicit by specifying the time during which each pump is
on/off. In this study, two new explicit representations based on timecontrolled
triggers were analyzed, where the maximum number of
pump switches was established beforehand, and the schedule may
contain fewer switches than the maximum. The optimal operation of
pumping stations was determined using a Jumping Particle Swarm
Optimization (JPSO) algorithm to achieve the minimum energy cost.
The model integrates JPSO optimizer and EPANET hydraulic
network solver. The optimal pump operation schedule of VanZyl
water distribution system was determined using the proposed model
and compared with those from Genetic and Ant Colony algorithms.
The results indicate that the proposed model utilizing the JPSO
algorithm is a versatile management model for the operation of realworld
water distribution system.
Abstract: This paper deals with the problem of management of
information resources in libraries of the public institution Sultan
Moulay Slimane University (SMSU) in order to analyze the
satisfaction of the readers, and allow university leaders to make better
strategic and instant decisions. For this, the integration of an
integrated management decision library system is a priority program
of higher education, as part of the Digital Morocco, which has a
proactive policy to develop the use of new technologies information
and communication in higher institutions. This operational
information system can provide better services to the students and for
the leaders. Our approach is to integrate the tools of business
intelligence (BI) in the library management by using power BI.
Abstract: The current study aims to highlight the loading
characteristics impact on the time evolution (focusing particularly on
long term effects) of the deformation of realized reinforced concrete
beams. Namely the tension stiffening code provisions (i.e. within
Eurocode 2) are reviewed with a clear intention to reassess their
operational value and predicting capacity. In what follows the
experimental programme adopted along with some preliminary
findings and numerical modeling attempts are presented. For a range of long slender reinforced concrete simply supported
beams (4200 mm) constant static sustained and repeated cyclic
loadings were applied mapping the time evolution of deformation.
All experiments were carried out at the Heavy Structures Lab of the
University of Leeds. During tests the mid-span deflection, creep
coefficient and shrinkage strains were monitored for duration of 90
days. The obtained results are set against the values predicted by
Eurocode 2 and the tools within an FE commercial package (i.e.
Midas FEA) to yield that existing knowledge and practise is at times
over-conservative.
Abstract: In this study, failure analysis of pipe system at a micro
hydroelectric power plant is investigated. Failure occurred at the pipe
system in the powerhouse during shut down operation of the water
flow by a valve. This locking had caused a sudden shock wave, also
called “Water-hammer effect”, resulting in noise and inside pressure
increase. After visual investigation of the effect of the shock wave on
the system, a circumference crack was observed at the pipe flange
weld region. To establish the reason for crack formation, calculations
of pressure and stress values at pipe, flange and welding seams were
carried out and concluded that safety factor was high (2.2), indicating
that no faulty design existed. By further analysis, pipe system and
hydroelectric power plant was examined. After observations it is
determined that the plant did not include a ventilation nozzle (air
trap), that prevents the system of sudden pressure increase inside the
pipes which is caused by water-hammer effect. Analyses were carried
out to identify the influence of water-hammer effect on inside
pressure increase and it was concluded that, according Jowkowsky’s
equation, shut down time is effective on inside pressure increase. The
valve closing time was uncertain but by a shut down time of even one
minute, inside pressure would increase by 7.6 bar (working pressure
was 34.6 bar). Detailed investigations were also carried out on the
assembly of the pipe-flange system by considering technical
drawings. It was concluded that the pipe-flange system was not
installed according to the instructions. Two of five weld seams were
not applied and one weld was carried out faulty. This incorrect and
inadequate weld seams resulted in; insufficient connection of the pipe
to the flange constituting a strong notch effect at weld seam regions,
increase in stress values and the decrease of strength and safety
factor.
Abstract: Nitrification is essential to biological processes
designed to remove ammonia and/or total nitrogen. It removes excess
nitrogenous compound in wastewater which could be very toxic to
the aquatic fauna or cause serious imbalance of such aquatic
ecosystem. Efficient nitrification is linked to an in-depth knowledge
of the structure and dynamics of the nitrifying community structure
within the wastewater treatment systems. In this study, molecular
technique was employed for characterizing the microbial structure of
activated sludge [ammonia oxidizing bacteria (AOB) and nitrite
oxidizing bacteria (NOB)] in a municipal wastewater treatment with
intention of linking it to the plant efficiency. PCR based phylogenetic
analysis was also carried out. The average operating and
environmental parameters as well as specific nitrification rate of plant
was investigated during the study. During the investigation the average temperature was 23±1.5oC.
Other operational parameters such as mixed liquor suspended solids
and chemical oxygen demand inversely correlated with ammonia
removal. The dissolved oxygen level in the plant was constantly
lower than the optimum (between 0.24 and 1.267 mg/l) during this
study. The plant was treating wastewater with influent ammonia
concentration of 31.69 and 24.47 mg/L. The influent flow rates
(ML/Day) was 96.81 during period. The dominant nitrifiers include:
Nitrosomonas spp. Nitrobacter spp. and Nitrospira spp. The AOB
had correlation with nitrification efficiency and temperature. This
study shows that the specific ammonia oxidizing rate and the specific
nitrate formation rates can serve as good indicator of the plant overall
nitrification performance.
Abstract: This paper addresses minimizing the makespan of the
distributed permutation flow shop scheduling problem. In this
problem, there are several parallel identical factories or flowshops
each with series of similar machines. Each job should be allocated to
one of the factories and all of the operations of the jobs should be
performed in the allocated factory. This problem has recently gained
attention and due to NP-Hard nature of the problem, metaheuristic
algorithms have been proposed to tackle it. Majority of the proposed
algorithms require large computational time which is the main
drawback. In this study, a general variable neighborhood search
algorithm (GVNS) is proposed where several time-saving schemes
have been incorporated into it. Also, the GVNS uses the sophisticated
method to change the shaking procedure or perturbation depending
on the progress of the incumbent solution to prevent stagnation of the
search. The performance of the proposed algorithm is compared to
the state-of-the-art algorithms based on standard benchmark
instances.
Abstract: In many countries, governments have been promoting the involvement of private sector entities to enter into long-term agreements for the development and delivery of large infrastructure projects, with a focus on overcoming the limitations upon public fund of the traditional approach. The involvement of private sector through public private partnerships (PPP) brings in new capital investments, value for money and additional risks to handle. Worldwide research studies have shown that an objective, systematic, reliable and useroriented risk assessment process and an optimal allocation mechanism among different stakeholders is crucial to the successful completion. In this framework, this paper, which is the first stage of a research study, aims to identify the main risks for the delivery of PPP projects. A review of cross-countries research projects and case studies was performed to map the key risks affecting PPP infrastructure delivery. The matrix of mapping offers a summary of the frequency of factors, clustered in eleven categories: construction, design, economic, legal, market, natural, operation, political, project finance, project selection and relationship. Results will highlight the most critical risk factors, and will hopefully assist the project managers in directing the managerial attention in the further stages of risk allocation.
Abstract: As per the statistical data, the Doubly-fed Induction
Generator (DFIG) based wind turbine with variable speed and
variable pitch control is the most common wind turbine in the
growing wind market. This machine is usually used on the grid
connected wind energy conversion system to satisfy grid code
requirements such as grid stability, Fault Ride Through (FRT), power
quality improvement, grid synchronization and power control etc.
Though the requirements are not fulfilled directly by the machine, the
control strategy is used in both the stator as well as rotor side along
with power electronic converters to fulfil the requirements stated
above. To satisfy the grid code requirements of wind turbine, usually
grid side converter is playing a major role. So in order to improve the
operation capacity of wind turbine under critical situation, the
intensive study of both machine side converter control and grid side
converter control is necessary In this paper DFIG is modeled using
power components as variables and the performance of the DFIG
system is analysed under grid voltage fluctuations. The voltage
fluctuations are made by lowering and raising the voltage values in
the utility grid intentionally for the purpose of simulation keeping in
view of different grid disturbances.
Abstract: The application of cold Radio-Frequency (RF) plasma
in the conservation of cultural heritage became important in the last
decades due to the positive results obtained in decontamination
treatments. This paper presents an equipment especially designed for cold RF
plasma application on paper documents, developed within a research
project. The equipment consists in two modules: the first one is
designed for decontamination and cleaning treatments of any type of
paper supports, while the second one can be used for coating friable
papers with adequate polymers, for protection purposes. All these
operations are carried out in cold radio-frequency plasma, working in
gaseous nitrogen, at low pressure. In order to optimize the equipment parameters ancient paper
samples infested with microorganisms have been treated in nitrogen
plasma and the decontamination effects, as well as changes in surface
properties (color, pH) were assessed. The microbiological analysis
revealed complete decontamination at 6 minutes treatment duration;
only minor modifications of the surface pH were found and the
colorimetric analysis showed a slight yellowing of the support.
Abstract: Anammox is a novel and promising technology that has changed the traditional concept of biological nitrogen removal. The process facilitates direct oxidation of ammonical nitrogen under anaerobic conditions with nitrite as an electron acceptor without addition of external carbon sources. The present study investigated the feasibility of Anammox Hybrid Reactor (AHR) combining the dual advantages of suspended and attached growth media for biodegradation of ammonical nitrogen in wastewater. Experimental unit consisted of 4 nos. of 5L capacity AHR inoculated with mixed seed culture containing anoxic and activated sludge (1:1). The process was established by feeding the reactors with synthetic wastewater containing NH4-H and NO2-N in the ratio 1:1 at HRT (hydraulic retention time) of 1 day. The reactors were gradually acclimated to higher ammonium concentration till it attained pseudo steady state removal at a total nitrogen concentration of 1200 mg/l. During this period, the performance of the AHR was monitored at twelve different HRTs varying from 0.25-3.0 d with increasing NLR from 0.4 to 4.8 kg N/m3d. AHR demonstrated significantly higher nitrogen removal (95.1%) at optimal HRT of 1 day. Filter media in AHR contributed an additional 27.2% ammonium removal in addition to 72% reduction in the sludge washout rate. This may be attributed to the functional mechanism of filter media which acts as a mechanical sieve and reduces the sludge washout rate many folds. This enhances the biomass retention capacity of the reactor by 25%, which is the key parameter for successful operation of high rate bioreactors. The effluent nitrate concentration, which is one of the bottlenecks of anammox process was also minimised significantly (42.3-52.3 mg/L). Process kinetics was evaluated using first order and Grau-second order models. The first-order substrate removal rate constant was found as 13.0 d-1. Model validation revealed that Grau second order model was more precise and predicted effluent nitrogen concentration with least error (1.84±10%). A new mathematical model based on mass balance was developed to predict N2 gas in AHR. The mass balance model derived from total nitrogen dictated significantly higher correlation (R2=0.986) and predicted N2 gas with least error of precision (0.12±8.49%). SEM study of biomass indicated the presence of heterogeneous population of cocci and rod shaped bacteria of average diameter varying from 1.2-1.5 mm. Owing to enhanced NRE coupled with meagre production of effluent nitrate and its ability to retain high biomass, AHR proved to be the most competitive reactor configuration for dealing with nitrogen laden wastewater.
Abstract: The present study is a functional analysis of the
relationship between castes which indicates the dynamics of the caste
structure in the rural setting. The researcher has tried to show both
the cooperation and competition on important ceremonial and social
occasions. The real India exists in the villages, so we need to know
about their solidarity and also what the village life is and has been
shaping into. We need to emphasize a microcosmic study of Indian
rural life. Furthermore, caste integration is an acute problem country
faces today. To resolve this we are required to know the dynamics of
behavior of the people of different castes and for the study of the
caste dynamics a study of caste relations are needed. The present
study is an attempt in this direction.
Abstract: Automation of airport operations can greatly improve
ground movement efficiency. In this paper, we study the speed profile
design problem for advanced airport ground movement control and
guidance. The problem is constrained by the surface four-dimensional
trajectory generated in taxi planning. A decomposed approach of two
stages is presented to solve this problem efficiently. In the first stage,
speeds are allocated at control points, which ensure smooth speed
profiles can be found later. In the second stage, detailed speed profiles
of each taxi interval are generated according to the allocated control
point speeds with the objective of minimizing the overall fuel
consumption. We present a swarm intelligence based algorithm for the
first-stage problem and a discrete variable driven enumeration method
for the second-stage problem, since it only has a small set of discrete
variables. Experimental results demonstrate the presented
methodology performs well on real world speed profile design
problems.