Abstract: In industrial environments, the heat exchanger is a
necessary component to any strategy of energy conversion. Much of
thermal energy used in industrial processes passes at least one times
by a heat exchanger, and methods systems recovering thermal
energy.
This survey paper tries to presents in a systemic way an sample
control of a heat exchanger by comparison between three controllers
LQR (linear quadratic regulator), PID (proportional, integrator and
derivate) and Pole Placement. All of these controllers are used mainly
in industrial sectors (chemicals, petrochemicals, steel, food
processing, energy production, etc…) of transportation (automotive,
aeronautics), but also in the residential sector and tertiary (heating, air
conditioning, etc...) The choice of a heat exchanger, for a given
application depends on many parameters: field temperature and
pressure of fluids, and physical properties of aggressive fluids,
maintenance and space. It is clear that the fact of having an
exchanger appropriate, well-sized, well made and well used allows
gain efficiency and energy processes.
Abstract: This paper deals with the assessment of faulted area around an industrial customer connected to a particular electric grid that will cause a certain sag magnitude on this customer. The faulted (critical or exposed) area’s length is calculated by adding all line lengths in the neighborhood of the critical node (customer). The applied method is the so-called Method of Critical Distances. By using advanced short-circuit analysis, the Critical Area can be accurately calculated for radial and meshed power networks due to all symmetrical and asymmetrical faults. For the demonstration of the effectiveness of the proposed methodology, a study case is used.
Abstract: This paper presents the use of phasor bond graphs to
obtain the steady-state behavior of a synchronous generator. The
phasor bond graph elements are built using 2D multibonds, which
represent the real and imaginary part of the phasor. The dynamic
bond graph model of a salient-pole synchronous generator is showed,
and verified viz. a sudden short-circuit test. The reduction of the
dynamic model into a phasor representation is described. The
previous test is executed on the phasor bond graph model, and its
steady-state values are compared with the dynamic response. Besides,
the widely used power (torque)-angle curves are obtained by means
of the phasor bond graph model, to test the usefulness of this model.
Abstract: This paper proposes a phasor representation of
electrical networks by using bond graph methodology. A so-called
phasor bond graph is built up by means of two-dimensional bonds,
which represent the complex plane. Impedances or admittances are
used instead of the standard bond graph elements. A procedure to
obtain the steady-state values from a phasor bond graph model is
presented. Besides the presentation of a phasor bond graph library in
SIDOPS code, also an application example is discussed.
Abstract: In this article our research focused on study of basic physical and mechanical parameters of polymer-cement repair materials is presented. Namely the influence of applied aggregates in combination with active admixture is specially considered. New formulas which were exposed in ambient with temperature even to 1000°C were suggested. Subsequently densities and strength characteristics including their changes were evaluated. Selected samples were analyzed using electron microscope. The positive influence of porous aggregates based on sintered ash was definitely demonstrated. Further it was found than in terms of thermal resistance the effective micro silica amount represents 5% to 7.5% of cement weight.
Abstract: The adsorption efficiency of various adsorbents for the removal of Zn(II) ions from the waste printing developer was studied in laboratory batch mode. The maximum adsorption efficiency of 94.1% was achieved with unfired clay pellets size (d ≈ 15 mm). The obtained values of adsorption efficiency was subjected to the independent-samples t test in order to investigate the statistically significant differences of the investigated adsorbents for the effective removal of Zn(II) ions from the waste printing developer. The most statistically significant differences of adsorption efficiencies for Zn(II) ions removal were obtained between unfired clay pellets (size d ≈ 15 mm) and activated carbon (½t½=6.909), natural zeolite (½t½=10.380), mixture of activated carbon and natural zeolite (½t½=9.865), bentonite (½t½=6.159), fired clay (½t½=6.641), fired clay pellets (size d ≈ 5 mm) (½t½=6.678), fired clay pellets (size d ≈ 8 mm) (½t½=3.422), respectively.
Abstract: Because of the outbreak of mad cow disease and bird flu, consumers have become more concerned with quality and safety of meat and poultry. As a consequence, meat traceability has been implemented as a tool to raise the standard in the meat production industry. In Thailand, while traceability is relatively common among the manufacturer-wholesaler-retailers cycle, it is rarely used as a marketing tool specifically designed to persuade consumers who are the actual meat endusers. Therefore, the present study attempts to understand what influences consumers to spread their words-of-mouth (WOM) regarding meat with traceability by conducting a study in Thailand where research in this area is rather scant. Data were collected from one hundred and sixty-seven consumers in the northeastern region and analyzed with SEM. The study results reveal that perceived usefulness of traceability system, social norms, and product class knowledge are significant antecedents where consumers spread positive words regarding meat with traceability system. A number of theoretical and managerial implications as well as future study directions are offered at the end of this study report.
Abstract: Local utilities often face problems of local industrial
wastes, storm water disposal due to existing strict regulations. For
many local industries, the problem of wastewater treatment and
discharge into surface reservoirs can’t be solved through the use of
conventional biological treatment techniques. Current discharge
standards require very strict removal of a number of impurities such
as ammonia, nitrates, phosphate, etc. To reach this level of removal,
expensive reagents and sorbents are used.
The modern concept of rational water resources management
requires the development of new efficient techniques that provide
wastewater treatment and reuse.
As RO membranes simultaneously reject all dissolved impurities
such as BOD, TDS, ammonia, phosphates etc., they become very
attractive for the direct treatment of wastewater without biological
stage. To treat wastewater, specially designed membrane "open
channel" modules are used that do not possess "dead areas" that cause
fouling or require pretreatment. A solution to RO concentrate
disposal problem is presented that consists of reducing of initial
wastewater volume by 100 times. Concentrate is withdrawn from
membrane unit as sludge moisture. The efficient use of membrane
RO techniques is connected with a salt balance in water system.
Thus, to provide high ecological efficiency of developed techniques,
all components of water supply and wastewater discharge systems
should be accounted for.
Abstract: The optimization of biological systems, which is a branch of metabolic engineering, has generated a lot of industrial and academic interest for a long time. In the last decade, metabolic engineering approaches based on mathematical optimizations have been used extensively for the analysis and manipulation of metabolic networks. In practical optimization of metabolic reaction networks, designers have to manage the nature of uncertainty resulting from qualitative characters of metabolic reactions, e.g., the possibility of enzyme effects. A deterministic approach does not give an adequate representation for metabolic reaction networks with uncertain characters. Fuzzy optimization formulations can be applied to cope with this problem. A fuzzy multi-objective optimization problem can be introduced for finding the optimal engineering interventions on metabolic network systems considering the resilience phenomenon and cell viability constraints. The accuracy of optimization results depends heavily on the development of essential kinetic models of metabolic networks. Kinetic models can quantitatively capture the experimentally observed regulation data of metabolic systems and are often used to find the optimal manipulation of external inputs. To address the issues of optimizing the regulatory structure of metabolic networks, it is necessary to consider qualitative effects, e.g., the resilience phenomena and cell viability constraints. Combining the qualitative and quantitative descriptions for metabolic networks makes it possible to design a viable strain and accurately predict the maximum possible flux rates of desired products. Considering the resilience phenomena in metabolic networks can improve the predictions of gene intervention and maximum synthesis rates in metabolic engineering. Two case studies will present in the conference to illustrate the phenomena.
Abstract: The approach in analyzing defects on different pipe lines is conducted through Failure Assessment Diagram (FAD). These methods of analyses have further extended in recent years. This approach is used to identify and stress out a solution for the defects which randomly occur with gas pipes such are corrosion defects, gauge defects, and combination of defects where gauge and dents are included. Few of the defects are to be analyzed in this paper where our main focus will be the fracture of cast Iron pipes, elastic-plastic failure and plastic collapse of X52 steel pipes for gas transport. We need to conduct a calculation of probability of the defects in order to predict and avoid such costly defects.
Abstract: We offer a new technique for research of stability of current sheaths in space plasma taking into account the effect of polarization. At the beginning, the found perturbation of the distribution function is used for calculation of the dielectric permeability tensor, which simulates inhomogeneous medium of a current sheath. Further, we in the usual manner solve the system of Maxwell's equations closed with the material equation. The amplitudes of Fourier perturbations are considered to be exponentially decaying through the current sheath thickness. The dispersion equation follows from the nontrivial solution requirement for perturbations of the electromagnetic field. The resulting dispersion equation allows one to study the temporal and spatial characteristics of instability modes of the current sheath (within the limits of the proposed model) over a wide frequency range, including low frequencies.
Abstract: This study focuses on the application of sensory thermography, as a non-invasive method to evaluate the musculoskeletal injuries that industry workers performing Highly Repetitive Movements (HRM) may acquire. It was made at a wireless company having the target of analyze temperatures in worker’s wrists, elbows and shoulders in workstations during their activities, this thru sensorial thermography with the goal of detecting maximum temperatures (Tmax) that could indicate possible injuries. The tests were applied during 3 hours for only 2 workers that work in workstations where there’s been the highest index of injuries and accidents. We were made comparisons for each part of the body that were study for both because of the similitude between the activities of the workstations; they were requiring both an immediate evaluation. The Tmax was recorder during the test of the worker 2, in the left wrist, reaching a temperature of 35.088ºC and with a maximum increase of 1.856°C
Abstract: In the present study, RAPD-PCR was used to assess genetic diversity of the rye including landrances and new rye cultivars coming from Central Europe and the Union of Soviet Socialist Republics (SUN). Five arbitrary random primers were used to determine RAPD polymorphism in the set of 38 rye genotypes. These primers amplified altogether 43 different DNA fragments with an average number of 8.6 fragments per genotypes. The number of fragments ranged from 7 (RLZ 8, RLZ 9 and RLZ 10) to 12 (RLZ 6). DI and PIC values of all RAPD markers were higher than 0.8 that generally means high level of polymorphism detected between rye genotypes. The dendrogram based on hierarchical cluster analysis using UPGMA algorithm was prepared. The cultivars were grouped into two main clusters. In this experiment, RAPD proved to be a rapid, reliable and practicable method for revealing of polymorphism in the rye cultivars.
Abstract: In this study, we developed a complementary electrochromic device consisting of WO3 and NiO films fabricated by rf-magnetron sputtered. The electrochromic properties of WO3 and NiO films were investigated using cyclic voltammograms (CV), performed on WO3 and NiO films immersed in an electrolyte of 1 M LiClO4 in propylene carbonate (PC). Optical and electrochemical of the films, as a function of coloration–bleaching cycle, were characterized using an UV-Vis-NIR spectrophotometer and cyclic voltammetry (CV). After investigating the properties of WO3 film, NiO film, and complementary electrochromic devices, we concluded that this device provides good reversibility, low power consumption of -2.5 V in color state, high variation of transmittance of 58.96%, changes in optical density of 0.81 and good memory effect under open-circuit conditions. In addition, electrochromic component penetration rate can be retained below 20% within 24h, showing preferred memory features; however, component coloring and bleaching response time are about 33s.
Abstract: The elements for success in the service industry for many organizations have been studied and quantified. They range from effective performance evaluation and management to adequately implementing seven P’s. However, the success story of every organization is unique. What might work for one organization might not for another as every company is inherently distinctive. In this paper, the strategic framework behind the success of Liberty Automobiles Dubai is captured. The primary data necessary for this paper was collected through in-depth interviews with the managers for sales, service and marketing as well as the group general manager. Subsequently, the key areas that led to the success of Liberty Autos will be discussed in this paper.
Abstract: To avoid battery assisted tags with limited lifetime batteries, it is proposed here to replace them by energy harvesting
systems, able to feed from local environment. This would allow total
independence to RFID systems, very interesting for applications
where tag removal from its location is not possible. Example is here
described for luggage safety in airports, and is easily extendable to similar situation in terms of operation constraints. The idea is to fix
RFID tag with energy harvesting system not only to identify luggage
but also to supply an embedded microcontroller with a sensor
delivering luggage weight making it impossible to add or to remove
anything from the luggage during transit phases. The aim is to
optimize the harvested energy for such RFID applications, and to
study in which limits these applications are theoretically possible.
Proposed energy harvester is based on two energy sources:
piezoelectricity and electromagnetic waves, so that when the luggage
is moving on ground transportation to airline counters, the piezo
module supplies the tag and its microcontroller, while the RF module
operates during luggage transit thanks to readers located along the
way. Tag location on the luggage is analyzed to get best vibrations, as
well as harvester better choice for optimizing the energy supply
depending on applications and the amount of energy harvested during
a period of time. Effects of system parameters (RFID UHF
frequencies, limit distance between the tag and the antenna necessary
to harvest energy, produced voltage and voltage threshold) are
discussed and working conditions for such system are delimited.
Abstract: The reported study focuses on pre-service teachers’ professional development during the teaching practice. The cohort studied comprised participants in their final year in the Bachelor of Arts and Bachelor of Science with Graduate Certificate in Education programmes of a university in Fiji. Analysis of the data obtained using a survey questionnaire indicates that overall, the pre-service teachers were satisfied with the practicum experience. This is assumed to demonstrate that the practicum experience contributed well towards their professional preparation for work expected of them in Fiji secondary schools. Participants also identified some concerns as needing attention. To conclude, the paper provides suggestions for improving the preparation of teachers by strengthening the identified areas of the practicum offered by the university. The study has implications for other teacher education providers in small developing island states and even beyond for the purpose of enhancing learning in student teachers’ for future work.
Abstract: Following implementation of a master’s level graduate degree program in technology, a research-based assessment of the program was undertaken to determine how well the program met its goals and objectives, and the impact of the degree program on the objectives and the needs of its graduates. Upon review of the survey data, it was concluded that the program was meeting its goals and objectives, and that the directed project option should be encouraged.
Abstract: This paper aims to study the role and activities of the participants and the impact of activities created in the local area in order to sustainably develop the local areas. This study applied both qualitative and quantitative approaches presented in descriptive style; the data was collected via survey, observation and in-depth interviews with samples. The results illustrated five sorts of roles of participants of the Cicada Walking-street and four types of creative activities; recreation based, art based, cultural based, and live events. Integration of local characteristics, arts and cultures were presented creatively and interestingly. Participants are various. The roles of the participants found in the Cicada Market are group of the property and area management, entrepreneurs, leisure (entertaining persons), local people, and tourists. The good impacts on local communities are those in terms of economy, environmental friendly and local arts and cultures promoting. On the other hand, the traffic congestion, waste and the increasing of energy consumption are negative impacts from area development.
Abstract: This research paper is aimed to examine a relationship between the service marketing mix and customers’ frequency of use of service at Mercedes Benz Auto Repair Centres under Thonburi Group, Thailand. Based on 2,267 customers who used the service of Thonburi Group’s Auto Repair Centres as the population, the sampling of this research was a total of 340 samples, by use of Probability Sampling Technique. Systematic Random Sampling was applied by use of questionnaire in collecting the data at Thonburi Group’s Auto Repair Centres. Mean and Pearson’s basic statistical correlations were utilized in analyzing the data. The study discovered a medium level of customers’ perception towards product and service of Thonburi Group’s Auto Repair Centres, price, place or distribution channel and promotion. People who provided service were perceived also at a medium level, whereas the physical evidence and service process were perceived at a high level. Furthermore, there appeared a correlation between the physical evidence and service process, and customers’ frequency of use of automobile service per year.