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The direct-injection (DI) and turbocharging strategies are recently adopted for spark-ignition (SI) engines in order to achieve better fuel economy and lower pollutant emissions. A comprehensive analysis is required in order to evaluate the effects of aforementioned strategies on in-cylinder combustion processes. The second law analysis is a proficient thermodynamic tool which is used for identifying irreversibilities and exploring the possibilities of thermal systems optimisation. The present work aims at carrying out an exergetic analysis of a downsized turbocharged DI SI engine. The engine is fuelled with E10 (gasoline with 10% of ethanol content) while experimental data is acquired for different engine operating conditions. The exergetic analysis identified the combustion irreversibilities. Moreover, a comparison between second law analyses of a previously analysed port fuel injection (PFI) naturally aspirated SI engine and turbocharged DI SI engine is also presented. The study concluded with the potential benefits and drawbacks of newly adopted strategies for SI engines.

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Introduction: Errors are frequent in health care and Emergency Departments are one of the riskiest areas due to frequent changes of team composition, complexity and variety of the cases and difficulties encountered in managing multiple patients. As the majority of clinical errors are the results of human factors and not technical in nature or due to the lack of knowledge, a training focused on these factors appears to be necessary. Crisis resource management (CRM), a tool that was developed initially by the aviation industry and then adopted by different medical specialties as anesthesia and emergency medicine, has been associated with decreased error rates.

Social networks are increasingly becoming an outlet that is more and more powerful in spreading news and influence individuals. Compared with other traditional media outlets such as newspaper, radio, and television, social networks empower users to spread their ideological message and/or to deliver target advertising very efficiently in terms of both cost and time. In this article, the authors focus on efficiently finding dominating sets in social networks for the classical dominating set problem as well as for two related problems: partial dominating sets and d-hop dominating sets. They will present algorithms for determining efficiently a good approximation for the social network minimum dominating sets for each of the three variants. The authors ran an extensive suite of experiments to test the presented algorithms on several datasets that include real networks made available by the Stanford Network Analysis Project and synthetic networks that follow the power-law and random models that they generated for this work. The performed experiments show that the selection of the algorithm that performs best to determine efficiently the dominating set is dependent of network characteristics and the order of importance between the size of the dominating set and the time required to determine such a set.

Nuclear experimental instrumentation frequently includes the usage of thin-walled (metallic sheathed) thermocouples passing through the boundaries of pressure vessels. This is accomplished by sealing the thermocouples by brazing through special design fittings (passages) which are later sealed / welded to the body of the vessel.Two are the challenges to face : (a) the manufacture of the instrumented passage (b) its mandatory qualification, according to relevant standards. Even the brazing qualification standards are more flexible than for welding, the peculiar situation of nuclear instrumentation still needs special consideration and it is not properly covered by the regular standards.The paper describes the experience of the authors in manufacture of the instrumented passages with steel or Inconel sheathed thermocouples, along with some other known projects, in conjunction with applicability of relevant standards: ASME code, AWS standards, national standards. Since it is about pressure vessels, ASME prescriptions are mandatory in Romania; other standards may serve as valuable sources for the “engineering judgment” allowed and recommended by ASME code.The main problem in such specialty brazing qualification is that for some combinations of base metals and filler (imposed by application), one cannot avoid the significant fragilization due to a tremendous increase of hardness in the brazing area. Base material erosion is added and the effect is catastrophic : sectioning the thermocouples at the slightest movement. For example, brazing Inconel thin-walled tubes with BNi-7 is very hard to control – experimental data and images are included in the paper to illustrate this.Therefore, special means must be applied both in fabrication and in qualification, in order to ensure the product is functional and safe, even being fragile. This approach can be found in French design of irradiation devices, being also considered in the French code for design and construction of experimental reactors and irradiation devices. Being known that French experience in this field is vast, their approach makes us confident that our brazing technique is not wrong but the problem is to be solved through ‘smart’ design and specific procedures. Consequently a tentative set of domestic rules for work and qualification is proposed for discussion and further improvement.

Introduction: Most children with fever without source will have a self limited viral infection though a small percent will develop a serious bacterial infection (SBI) like urinary tract infection, pneumonia, bacteraemia, meningitis or sepsis. The challenge facing practitioners is to distinguish between these two groups and currently biomarkers, like C-reactive protein (CRP) and Procalcitonin (PCT), are available for this purpose. The aim of the current study was to identify SBI in infants with fever without an identifiable cause using the recently introduced “Lab-score” combining C-reactive protein, procalcitonin and urine dipstick results.

Sol-gel chemistry allows the immobilization of organic molecules of biological origin on suibtable solid supports, permitting their integration into biosensing devices widening the possibility of local applications. The present work is an application of this principle, where the link between electrical receptor platform and the antibody acting as biorecognition element is made by sol-gel chemistry. The immunosensor design was targeted for carcinoembryonic antigen (CEA), an important biomarker for screening the colorectal cancer, by electrochemical techniques, namely electrochemical impedance spectroscopy (EIS) and square wave voltammetry (SVW). The device displayed linear behavior to CEA in EIS and in SWV assays ranging from 0.50 to 1.5ng/mL, and 0.25 to 1.5ng/mL, respectively. The corresponding detection limits were 0.42 and 0.043 ng/mL. Raman spectroscopy was used to characterize the surface modifications on the conductive platform (FTO glass). Overall, simple sol-gel chemistry was effective at the biosensing design and the presented approach can be a potential method for screening CEA in point-of-care, due to the simplicity of fabrication, short response time and low cost.

This work is dealing with the self-generated torque that occurs within a 4WD military special automotive drivetrain. The mathematical model stated in this paper is confirmed by the means of multiple tests developed in real conditions. The tests were developed in order to reveal both transversal and longitudinal self-generated torque within the drivetrain, on different road surfaces. The present paper also introduces some new concepts, such is for instance the insensitive domain of a self-locking (or a progressively locking) differential. With the aid of this concept we can easier deal with the self-generated torque that is due to the increased internal friction of the differential. Moreover, a general, comprehensive theory can be further issued that could classify the self-locking differentials according to their internal friction and their locking coefficient variation.

Present paper aims at revealing a way to determine the cinematic misfit within a 4x4 vehicle’s inter-axle driveline, which is eventually the reason of the self-generated torque occurrence. We used experimental methods to determine the magnitude of the cinematic misfit. Within this frame, we used a vehicle that has a longitudinal (inter-axle) differential and we locked it, actually forcing the longitudinal transmission to work without differentiating the angular speeds on its output shafts. On the other hand, the tire radii were different, inducing the above-mentioned cinematic misfit that we were looking for. We also present the way we fit the transducers on the vehicle’s driveline components to measure the needed parameters. The paper also presents some theoretical considerations regarding the occurrence of the cinematic misfit and its way of generating closed power loops within the vehicle’s transmission.

This paper is the result of a research program which focused on the statistical dynamics of vehicles. Most of the inputs of man-machine-field system have a random variation, so a systemic and statistical analysis of vehicle dynamics is obvious. In our study, data were obtained by measuring the dynamic parameters of vehicles and engines. Testing program aimed to capture a large range of operating regimes. To analyze the data the authors have used neural networks. There was adopted a NNARX (Neural Network Auto-Regressive with eXogene inputs) model with 4 inputs, 5 hidden units and 1 output. It can be concluded that the development of mathematical modeling using non-linear neural network can ensure the desired accuracy, conveniently is obtained by increasing the number of neurons in the hidden laws.

Simulating the real-time working of a system a complex challenge that had been developed lately within almost all fields of activity, of course including mechanical engineering as well. If one wants to reveal the torque and angular speed distribution onto the elements of a planetary gearbox, issuing a virtual model was previously needed. This model should replicate both the physical structure and the real working behavior.The modeled and simulated gearbox is a planetary type one. The power flows along the gearbox throughout three simple planetary mechanisms (sun gear and crown type) by successively locking different components with the aid of some multi-plate clutches (acting as locking clutches or brakes). The simulation of the friction element’s engagement is achieved by introducing a physical signal that replaces the pressure of the hydraulic command system. We mention that the pressure evolution has been previously experimentally determined, in order to model the force that acts on the actuator’s piston that, at its turn, presses the plates.The paper reveals the working cycles of the friction elements as well as the working modes of the planetary sets. It also reveals the time histories of the power flowing throughout the gearbox. The friction elements are modeled considering their three working stages: fully disengaged, partially engaged and fully engaged. The planetary sets are modeled starting from Willis equation for the speed distribution. For the torque distribution we used the energy conservation law as well as the torque balance law.Should be also mentioned that the virtual simulating model took into account the effects of the twisting vibrations, spinning inertia of the mechanical components and shafts’ elasticity.

Sealing of nuclear fuel material inside the fuel element clad must create a leak-tight "safety barrier" to prevent the release of radioactive products to environment. High quality welds are mandatory to withstand harsh conditions (radiation, pressure, temperature, corrosion) making possible the safe operation of nuclear reactors. The joint design, material selection and welding technique must be combined by smartly balancing possible technological options to yield the best attainable quality for the intended purpose; these choices are discussed in the paper. For thin-walled clad to end-plug welding, heat flow pattern as determined by joint design and fitting accuracy proved to be crucial for the fusion boundary shape and moreover for the success rate in automate welding. Consequently, Finite Element Analysis of the transient thermal field during welding was performed, in order to determine the best compromise with reasonable machining precision for parts. The main features of the developed thermal model and some results illustrating its good predictions vs. actual welds are also presented. Helium-shielded pulsed welding was initially preferred to minimize HAZ, distortion and porosity but unfortunately important cast-to-cast variation in penetration was observed with Inconel-600 plugs, due to Marangoni effect. Extensive work was done to overcome this, mainly through variation of pulsing and of the shielding gas; depth-to-width ratio can be noticeably improved with no material addition. Out of welding classic cladding materials, studies were initiated at INR on joining oxide-dispersion strengthened (ODS) alloys and specialty austenitic formulations (e.g. 15/15Ti) since they are candidate materials of great interest for the next generation of nuclear reactors.

Teaching profession is one with the highest requirements regarding emotion labor. Even though previous studies (Sutton, 2004) showed that teachers engage in emotion management as part of their professional identity with the purpose of professional efficacy, it is not clear yet what are the motivational bases of this engagement. We assessed specific emotional regulation strategies adopted in the workplace, the intrinsic/extrinsic motivation for work, and several job characteristics in a sample of Romanian teachers with the aim to identify motivational dimensions associated with emotional labor.

The present paper presents an experiment conducted between November 2009 and February 2011. The main hypothesis of the study was that efficient time management, under the guidance of an educational counselor, lead to significant increases in students academic performances and, consequently, lead to academic success. A number of 130 participants with low academic performances after the first two semesters (October 2009 – February 2010 – First semester, March – June 2010 – The second semester) participated in the study. All participants had above average or superior intellectual abilities (according to baccalaureate results). The educational counselor elaborated individualized and flexible programs for each participant in the experimental condition according to students learning styles, circadian, and eating rhythms, and daily and weekly effort curves. The program included planning of all activities participants were to develop during the two months of the experimental intervention. The results confirmed the hypothesis, showing the efficiency of time management individualized programs.

AbstractThe somatic chromosomes and karyotype traits of three Romanian genotypes (coded as CB-1, S-16, L-4) of Hippophae rhamnoidesL. have been studied. Diploid chromosome number is 2n = 24. The karyomorphological data show that the complements have small chromosomes (1.33 ± 0.014 – 2.80±0.01 μm, for CB-1 genotype; 1.13 ± 0.029 – 2.90 ± 0.029 μm, for S-16; 1.15 ± 0.099 – 2.88 ± 0.024 μm, for L-4 genotype) and the length of haploid complements is 23.97 μm, for CB-1, 22.20 μm, for S-16, 21.73 μm, for L-4. In CB-1 and S-16 male genotypes, the putative Y-chromosome has larger sizes than X-chromosome and it is of metacentric type (CI = 45.77, r = 1.18, for CB-1; CI = 46.22, r = 1.15, for S-16). The L-4 female karyotype is constituted by twelve pairs of morphologically similar chromosomes. The karyotype formulae are 2n = 24 = 13m + 11sm (putative male: 22 + XY), for CB-1 genotype, 2n = 24 = 18m + 6sm (putative male: 22 + XY), for S-16 genotype, respectively 2n = 24 = 22m + 2sm (L-4 genotype, considered as female: 22 + XX). The small size of chromosomes (< 3μm), the presence of only two morphometric chromosome types and preponderance of metacentrics confer a relatively high degree of symmetry to the studied karyotypes. Our results show a low intraspecific karyotype variation.

Researcher about the human brain modeling has possible new design of control systems for complex processes. This paper presents a structural/functional analysis of an intelligent autonomous system based on human intelligent control system. Human information processing is a most complex process that integrates all structure of human brain. An information processing model assumes that cognition can be analyzed into aseries of stage, each represented as an hypothetical entity during which certain unique operations an performed an incoming information.