Small End Research Articles

Electrification and rural development: issues of scale in distributed generation

Despite the importance of electrification for economic and social development, over one billion people globally lack access to electricity, primarily in rural areas of developing countries. Alongside the traditional means of expanding access, large‐scale grid electrification, there exists another option for rural electrification: small‐scale and localized distributed generation (DG), often powered by renewable energy sources.DGsystems can be grid‐connected or off‐grid and can range in scale from less than 10 W solar lanterns at the small end to 60 MW biomass generation. AlthoughDGhas enabled some level of access to electricity for millions of people, little or no research has analyzed how the scale or level of access to electricity has shaped the ways that programs are financed or are viewed by governments, or the developmental impacts that various levels have on end‐users. This article reviews the literature on DG in developing countries and finds that large‐scaleDGsystems require a different set of approaches to finance, end‐user training, and public policy support than do small‐scaleDGsystems. Our review also reveals that even the smallest scaleDGsystems improve users' quality of life, yet access to electricity alone is not sufficient to achieve desired economic and social development goals. Policy makers, donors, non‐governmental organizations (NGOs), and other actors engaged in rural development must both (1) make decisions considering the scale ofDGprograms, and (2) reflect on end‐users' needs and productive uses for electricity if rural electrification projects are to result in long‐term development benefits.WIREs Energy Environ2015, 4:196–211. doi: 10.1002/wene.129This article is categorized under:Energy Policy and Planning > Economics and Policy

Clarification of the Terminology of the Major Human Salivary Glands: Acinus and Alveolus are not Synonymous

Discrepancies in the terminology of the major human salivary glands often appear in anatomical textbooks and tend to adversely affect student's learning experience in Microscopic Anatomy. The main culprit is the inconsistent description of the morphology of these glands secretory end pieces where "acinus" and "alveolus" are used interchangeably. The correct terminology originated from Malpighi (1687), repeated by Kölliker (1854), but over the years has been misinterpreted by prominent authors as a result of the nature of specimen preparation. This commentary is based on etymology, current standard light microscopy, research studies and consultation with experts. The overall objective of this publication is to recommend that textbooks should endeavour to modify the relevant descriptions about this terminology in their future editions. The most appropriate terminology for the major human salivary glands would be: (1) the parotid gland, entirely serous, should be called compound acinar glands; (2) the submandibular glands are mixed glands; their serous components are compound acinar while some of the mucinous areas are tubular with serous, crescents or demilunes, as acinar end pieces hence they should be named compound tubuloacinar glands; (3) the sublingual glands, mainly mucous glands with tubular shape, with small acinar end pieces that are serous crescents thence they should be called compound tubuloacinar glands.

A dearth of small particles in debris disks

A prescription for the fragment size distribution resulting from dust grain collisions is essential when modelling a range of astrophysical systems, such as debris disks and planetary rings. While the slope of the fragment size distribution and the size of the largest fragment are well known, the behaviour of the distribution at the small size end is theoretically and experimentally poorly understood. This leads debris disk codes to generally assume a limit equal to, or below, the radiation blow-out size. We use energy conservation to analytically derive a lower boundary of the fragment size distribution for a range of collider mass ratios. Focussing on collisions between equal-sized bodies, we apply the method to debris disks. For a given collider mass, the size of the smallest fragments is found to depend on collision velocity, material parameters, and the size of the largest fragment. We provide a physically motivated recipe for the calculation of the smallest fragment, which can be easily implemented in codes for modelling collisional systems. For plausible parameters, our results are consistent with the observed predominance of grains much larger than the blow-out size in Fomalhaut's main belt and in the Herschel cold debris disks.

Design and analysis of a connected broadband multi-piezoelectric-bimorph- beam energy harvester.

The rapid growth of remote, wireless, and microelectromechanical system (MEMS) devices over the past decades has motivated the development of a self-powered system that can replace traditional electrochemical batteries. Piezoelectric energy harvesters are ideal for capturing energy from mechanical vibrations in the ambient environment. Numerous studies have been made of this application of piezoelectric energy conversion; however, the narrow frequency operation band has limited its application to generate useful power. In this paper, a broadband energy harvester with an array/matrix of piezoelectric bimorphs connected by springs has been designed and analyzed based on the 1-D piezoelectric beam equations. The predicted result shows that the operational frequency band can be enlarged significantly by carefully adjusting the small end masses, length of the beam and spring stiffness. An optimal selection of the load impedance to realize the maximum power output is discussed. The results provide an important foundation for future broadband energy harvester design.

Effect of Karanja biodiesel blend on engine wear in a diesel engine

For large-scale and reliable implementation of biodiesel in transportation engines, its effects on engine wear and engine durability upon prolonged usage needs to be experimentally investigated. Therefore effects of 20% Karanja biodiesel blend (KOME20) on engine wear and durability was studied vis-à-vis mineral diesel in 250h long endurance test on a direct injection compression ignition (DICI) engine. Visual inspection of engine components for deposits indicted higher carbon deposits on piston top, cylinder head and injector tip for biodiesel fuelled engine. Relatively lower wear of valves, pistons, piston rings, liners and small end bearings of the connecting rods was observed for biodiesel fuelled engine. Wear of big end bearing of the connecting rods, main bearings and crank pins was found to be higher for biodiesel fuelled engine. Surface texture of cylinder liners remained in acceptable condition after the endurance test for mineral diesel as well as Karanja biodiesel blend. Despite higher carbon deposits and higher wear of some vital engine components, no operational problems were observed during the long-term endurance test for the biodiesel fueled engine.

Research Methods of the Performance of Plate Heat Exchanger

this paper introduces research of plate heat exchanger, and describes the working principle of a plate heat exchanger. Plate heat exchangers have many advantages.For example: high heat transfer efficiency, small end temperature, pressure drop, saving space, saving installation costs. This paper analysis performance of experiment test , making plate heat exchanger improved.

The Optimization of Small End Bushings of Connecting-Rod in Heavy-Load Diesel Engines

The mechanical fit between the connecting rod's small end and the bush is a typical interference fit. In this paper, an elastic-plastic finite element model of the assembly of the connecting rod and the bush is built based on ABAQUS simulation platform and simulation experiments are carried out by adopting the method of design of experiments. The magnitude of interference and the thickness of the bush are set as the test factors and the maximum radial deformation of the connecting rod’s small end hole, the radial contact pressure between the connecting rod and the bush, the plastic deformation of the bush and the fatigue strength safety coefficient of the connecting rod small end are set as the response variables. Based on the response surface equations, the multi-objective optimal approximate mathematical model is set up and the Pareto optimal set are gained and discussed.

ON THE MECHANICS OF ELLIPSOIDAL FULLERENES INSIDE OPEN CARBON NANOCONES: A NOVEL NUMERICAL APPROACH

In this research, mechanics of concentric ellipsoidal fullerenes inside open carbon nanocones (CNCs) is investigated. To this end, using continuum approximation in conjunction with Lennard-Jones (LJ) potential function, quadruple-integral expressions associated with van der Waals (vdW) potential energy and interaction force are first derived. For determination of these expressions, it is assumed that the fullerene molecule enters the open CNC through the small end or wide end. Thereafter, an efficient approach based on the differential quadrature (DQ) method is proposed to numerically evaluate the obtained quadruple integrals. The proposed method takes advantage of computing multidimensional integrals efficiently with using appropriate number of grid points. By introducing DQ-based operational matrices of differentiation and integration, the quadruple-integral expressions are estimated over their domains. Moreover, new semianalytical expressions are introduced in terms of triple integrals to evaluate vdW interactions. The validity and accuracy of the introduced numerical method are proved by comparing the results obtained through this method with ones achieved via the semianalytical expressions. The ease of implementation and quick answer of the demonstrated numerical solution enable us to comprehensively examine the effects of different geometrical parameters such as small end radius wide end radius and vertex angle of nanocone on the distributions of vdW potential energy and interaction force. The results reveal that the ellipsoidal fullerene undergoes an asymmetrical motion along the axis of open CNC.

The noradrenergic projection from the locus coeruleus to the cochlear root neurons in rats

The cochlear root neurons (CRNs) are key components of the primary acoustic startle circuit; mediating auditory alert and escape behaviors in rats. They receive a great variety of inputs which serve to elicit and modulate the acoustic startle reflex (ASR). Recently, our group has suggested that CRNs receive inputs from the locus coeruleus (LC), a noradrenergic nucleus which participates in attention and alertness. Here, we map the efferent projection patterns of LC neurons and confirm the existence of the LC-CRN projection using both anterograde and retrograde tract tracers. Our results show that each LC projects to the CRNs of both sides with a clear ipsilateral predominance. The LC axons terminate as small endings distributed preferentially on the cell body and primary dendrites of CRNs. Using light and confocal microscopy, we show a strong immunoreactivity for tyrosine hydroxylase and dopamine β-hydroxylase in these terminals, indicating noradrenaline release. We further studied the noradrenergic system using gene expression analysis (RT-qPCR) and immunohistochemistry to detect specific noradrenergic receptor subunits in the cochlear nerve root. Our results indicate that CRNs contain a noradrenergic receptor profile sufficient to modulate the ASR, and also show important gender-specific differences in their gene expression. 3D reconstruction analysis confirms the presence of sexual dimorphism in the density and distribution of LC neurons. Our study describes a coerulean noradrenergic projection to the CRNs that might contribute to neural processes underlying sensory gating of the ASR, and also provides an explanation for the gender differences observed in the behavioral paradigm.

Antipsychotic-Induced Weight Gain: Can the Energy Balance Gene Variants Help us Tip the Scales?

Identifying risk factors for drug-related side effects represents the foundation of pharmacogenomics. Prediction of risk for antipsychoticinduced weight gain (AIWG) is poor. This common side effect of antipsychotics [1] frequently leads to risk of relapse of psychopathology from dose reduction, drug substitution or noncompliance driven by health and psychological concerns. Yet, the individual variability of AIWG is striking, and family studies have suggested substantial genetic contributions to AIWG risk [2]. Currently, no genetic tests for AIWG are endorsed for clinical application. However, the strength of recent findings linking common variants in energy balance genes with AIWG raise the question – has the pharmacogenomics of AIWG reached clinical significance? Initial studies of the role of monoaminergic candidate gene variants as predictors of AIWG were mixed owing to small samples, population stratification and limited end point data. One exception has been a widely replicated association between a promoter SNP in HTR2C [3]. Nevertheless, variance in AIWG explained by the -759 SNP in HTR2C was small in comparison to AIWG’s estimated heritability, and thusly no consensus supports clinical HTR2C testing despite available commercial tests. AIWG is thought to be multi factorial and polygenic, paralleling obesity per se, and new research has pointed to a broader array of genes and systems hypothesized to underpin AIWG, suggested by the identif ication of over 30 genome-wide significant risk genes for obesity, as well as results from genome-wide pharmacogenomic analyses of the CATIE study of antipsychotic-treated adults with schizophrenia. In the CATIE analyses, weight gain and metabolic effects were significantly associated with

Resonance Tuning of a Multi-piezoelectric Bimorph Beams Energy Harvester Connected by Springs

Piezoelectric energy harvesters are ideal for capturing energy from mechanical vibrations in the ambient environment. Numerous studies have been made of this application of piezoelectric energy conversion; however, thus far researchers have encountered limitations in the amount of power that can be captured. In this paper, a frequency- adjustable energy harvester with an array of piezoelectric bimorphs connected by springs has been designed and analyzed based on the 1D piezoelectric beam equations. The result shows that the energy harvester is capable of operating in multiple frequencies, and the operating frequencies can be adjusted by changing the small end masses and spring stiffness. An optimal selection of the load impedance to realize the maximum power output is discussed. The power efficiency of the energy harvester has been analyzed as well.

Examining the correlations between drop size distribution parameters using data from two side-by-side 2D-video disdrometers

As part of a long-term observation campaign, over 5000 pair samples of temporally matched 1-minute averaged drop size distribution (DSD) measurements have been recorded by two side-by-side (frequently calibrated) 2D-video disdrometers. The measurement campaign was conducted in Huntsville, Alabama, over a ten-month period, and includes a variety of rain types and regimes. The datasets have been used to examine, (i) the relationship between the mass-weighted mean diameter (Dm) and the standard deviation of the mass spectrum (σM) without any assumption on the DSD form, and (ii) the relationship between the shape parameter (μ) and slope parameter (Λ) of the gamma form of the DSD. A number of methods were used to estimate μ and Λ, including: a normalizing procedure, the method of moments, the maximum likelihood method and the L-moment method. The physical validity of the σM–Dm relationship is examined by, (i) relating the estimated Dm versus the estimated σM from the same disdrometer datasets and, (ii) by ‘cross-relating’ Dm from one disdrometer with the corresponding σM from the second disdrometer dataset. The same procedures were repeated to examine the physical validity of the μ–Λ relation. It is shown that the transformed variable σM′=σMDm−1.65, which is uncorrelated with Dm, has a narrow histogram and that σM′≈constant can form a constraint which may well be applicable to other rain climatologies. For the μ–Λ relationship, the variation between μ from one unit and Λ by the second unit showed, as expected, larger scatter than using estimates from the same unit but not excessively so given that the μ estimates from the two units themselves show some instrument-to-instrument variability. While we cannot ascertain that the removal of any statistical correlations necessarily implies that the μ–Λ relation is physical, we have gone on to show that instrument limitations of accurately measuring the number concentration at the small drop end (D<0.5mm) are likely to be more important in giving rise to spuriously large μ values and related higher μ–Λ correlation, especially in light rain, and perhaps to a lesser extent in heavier rain.

Kinematics Analysis and Simulation of Small Satellite Docking Mechanism End Executor

In order to save space mission cost, prolonging the working life of the spacecraft and improving the flexibility and capable of performing various tasks should get more attention on orbit servicing technology. For the docking process of a new type of two independent service in-orbit spacecraft, this paper finished the kinematics analysis, for the whole docking capture process, two groups of different initial conditions and control function of the simulation analysis were finished by the ADAMS software. The results prove that the docking mechanism performance is very good, and reliable connection can be realized in the general initial conditions.

A25 超弾塑性特性を有するチタニウム合金を対象とした小径ミーリング加工に関する研究 : 工具被膜の最適化に関する検討(OS3 工具・ツーリング(1))

A25 超弾塑性特性を有するチタニウム合金を対象とした小径ミーリング加工に関する研究 : 工具被膜の最適化に関する検討(OS3 工具・ツーリング(1))

커넥팅로드 강건 설계 방안

Finite element analysis along with DOE scheme has been performed to obtain robust design of connecting rod assembly. An analysis was conducted with five loading steps. Fatigue analysis was done using commercial software FEMFAT and fatigue safety factors at the interested regions such as shank area of small end and big end were calculated. 27 design cases using 3 factors with 3 levels are constructed by design of experiment. Each case is simulated to find the most influential factors. Response for this study, maximum Von-Mises stress, has been used to determine main factors of connecting rod assembly. Among the 3 factors, compression load affected the response greatly. However, bolt assembly load and width of shank flat area showed a little influence to the response. Interaction effects among factors considered did not occur. Connecting rod assembly considered in this study showed its sensitivity to the noise factor such as compression load rather than design factor such as width of flat shank area.

Functional Proteomics Related to Energy Metabolism of Synaptosomes from Different Neuronal Systems of Rat Hippocampus during Aging

The effect of aging on hippocampus is often confounded by diseases that commonly occur in the elderly. In this research, functional proteomics was used to characterize age-related changes in energy metabolism of different neuronal pathways within the hippocampus of Wistar rats aged 2, 6, 12, 18, and 24 months. The "large" synaptosomes, derived from glutamatergic mossy fiber endings connecting granule cells of dentate gyrus with apical dendrites of CA3 pyramidal cells, and the "small" synaptosomes, derived from the cholinergic small nerve endings of septo-hippocampal fibers, whose projections reach CA1 pyramidal cells, were isolated. Because most brain disorders are associated with bioenergetic changes, the maximum rate (V(max)) of selected enzymes of glycolysis, Krebs cycle, glutamate and amino acids metabolism, and acetylcholine catabolism were evaluated. The results show that "large" and "small" synaptosomes possess specific and independent metabolic features coherently with the selective vulnerability of the respective hippocampal subfields to Alzheimer's disease and cerebral ischemia. This study represents a reliable model to study in vivo (i) the physiopathological molecular mechanisms of some brain diseases dependent on energy metabolism, (ii) the responsiveness to noxious stimuli, and (iii) the effects of drugs, discriminating their action sites at subcellular level.

Testing of Elastic Stresses and Limit Close-Bending Moments of Reducer Bends Subject to In-Plane Close-Bending Moments

Elastic stresses and limit close-bending moments of reducing elbows subject to in–plane close-bending moments were validated by limit element analysis (LMA) and testing. Results of LMA show that if the end bend moment M acts on small end while the large end is fixed, the largest movement acts on neutral line near the larger end, and large circumferential stress lies on inside surface near neutral lines but deflect to intrados of large end. For the same model, if the end bend moment M acts on large end while the small end is fixed, the largest movement acts on near the small end and lies on neutral line, and larger stress acts on small end and nearby. Results of testing show that stress character in tension stress and compressive stresses are consistent with the calculation results from formula. The limit bending moment calculation results from formula of reducing elbow is conservative, but is consistent with the formula of the limit bending moment, which is controlled by small end of reducing elbow.

Mechanics of single-walled carbon nanotubes inside open single-walled carbon nanocones

This study investigates the mechanical characteristics of single-walled carbon nanotubes (CNTs) inside open single-walled carbon nanocones (CNCs). New semi-analytical expressions are presented to evaluate van der Waals (vdW) interactions between CNTs and open CNCs. Continuum approximation, along with the the Lennard-Jones (LJ) potential function, is used in this study. The effects of geometrical parameters on alterations in vdW potential energy and the interaction force are extensively examined for the concentric CNT-open CNC configuration. The CNT is assumed to enter the nanocone either through the small end or the wide end of the cone. The preferred position of the CNT with respect to the nanocone axis is fully investigated for various geometrical parameters. The optimum nanotube radius minimizing the total potential energy of the concentric configuration is determined for different radii of the small end of the cone. The examined configuration generates asymmetric oscillation; thus, the system constitutes a nano-oscillator.

Crashworthiness analysis of glass fibre/epoxy laminated thin walled composite conical frusta under axial compression

The quasi-static axial compression of thin-walled E-glass fibre/epoxy resin reinforced (GFRP) composite conical frusta was carried out to study the crashworthiness of conical shells. The hollow frustrated E-glass fibre reinforced polymer (GFRP) conical specimens having semi-apical angle ranging from 15° to 27° were fabricated using random ply chopped, plain woven roving cross ply [0/90], and uni-directional angle ply [±60°] oriented mats to the required dimensions by hand layup process. Quasi-static axial compression load was applied over the small end of the conical specimen with a crosshead speed of 2mm/min using Universal Testing Machine (UTM). From the experiment results, the load deformation characteristics of thin GFRP composite conical shells were analyzed and the results were validated through finite element analysis package ABAQUS®. Further, the influence of ply orientation and the laminate wall thickness towards the energy absorbing capability of each GFRP conical specimen was studied. The buckling mode of collapse and the crushed zones of GFRP composite conical shells were also investigated to identify the collapse mechanisms involved in thin fibre/resin composite laminated conical specimens under quasi-static axial compression.

Mosaic and facet structures of epitaxial MnO films on Au (110)

Growth and annealing behavior of epitaxial MnO films on an Au (110)–(1×2) substrate have been studied by means of Auger electron spectroscopy, low energy electron diffraction, and scanning tunneling microscopy. MnO (110) films have been successfully grown by Mn evaporation in an oxygen atmosphere at room temperature with subsequent annealing to 750K. Instead of the expected (110)-like diffraction pattern complex mosaic and facet structures are found depending on annealing conditions. The mosaics are misfit-induced and display along [001] directions a misorientation of ±1.5°. At temperatures around 850K, mosaics gradually vanish and simultaneously a saw-tooth-like film morphology develops which is formed by ribbons of narrow (100) and (010) MnO facets. At temperatures above 850K the film partially dewets from the substrate, and the film transforms to three-dimensional MnO islands that have a roof-like shape where large roof sides and small end sides are composed by {100} and by {111} facets, respectively. The experiments corroborate the theoretical predicted tendency of facet formation of MnO (110) surfaces.