Top PDF STRESS ANALYSIS OF BICYCLE FRAME

STRESS ANALYSIS OF BICYCLE FRAME

STRESS ANALYSIS OF BICYCLE FRAME

In theoretical analysis the frame is treated as truss like structure and the stresses in various members of frame like top tube, down tube, seat tube, chain stay and seat stay are determined, considering various condition like, static start up, steady state paddling, vertical impact, horizontal impact, rear wheel braking. Also Finite Element Analysis is done considering the above conditions.

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Selected approaches of variables weighting in frame of composite indicator analysis

Selected approaches of variables weighting in frame of composite indicator analysis

As is written above, each variable can be given equal or different weight. Different authors such as Freundenberg [4], Saisana [12] or Svatošová [13] have outlined a range of ways of the weights´ determination for the tracked indicators. Also Grupp and Schubert [5] stress to use weights included in composite indicator, but authors mention that composite indicator should be sensitive to weight changes. The multivariate analysis of principal components seems to be appropriate for the exact appraisal of weights on the basis of primary indicators. Weights can be determined also subjectively on the basis of external decision; this approach has been chosen in the field of environment in the work [7].
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Hui-Liang Li, Dong Guo and Shi-Qing Peng

Hui-Liang Li, Dong Guo and Shi-Qing Peng

The cDNA encoding the R1-MYB transcription factor, designated as JcR1MYB1, was isolated from Jatropha curcas using rapid amplification of cDNA ends. JcR1MYB1 contains a 951 bp open reading frame that encodes 316 amino acids. The deduced JcR1MYB1 protein was predicted to possess the conserved, 56-amino acid-long DNA-binding domain, which consists of a single helix-turn-helix module and usually occurs in R1-MYBs. JcR1MYB1 is a member of the R1-MYB transcription factor subfamily. A subcellular localization study confirmed the nuclear localization of JcR1MYB1. Expression analysis showed that JcR1MYB1 transcripts accumulated in various examined tissues, with high expression levels in the root and low levels in the stem. JcR1MYB1 transcription was up-regulated by polyethyl- ene glycol, NaCl, and cold treatments, as well as by abscisic acid, jasmonic acid, and ethylene treatment. Analysis of transgenic tobacco plants over-expressing JcR1MYB1 indicates an inportant function for this gene in salt stress.
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Bamboo Bicycle – Past or Future?

Bamboo Bicycle – Past or Future?

Bamboo consists of cellulose, hemicelluloses and lignin. These components make up to 90 % of bamboo weight. Other constituents are proteins, fat, pectin, tannins, pigments and ashes. The physiology of bamboo depends on these constituents, which varies from species to species. The chemical composition of bamboo also varies with age. According to previous studies, with aging bamboo, there was a decline in the proportion of cellulose. Lignin is a constituent who gives stiffness and yellow color to bamboo. Also, a lignin proved to be highly resistant to alkaline actions. Non-cellulose component of bamboo affect on the properties such as density, strength, moisture, and the flexibility [2]. After heat treatment, the chemical composition of bamboo will be changed. Effects of heat on bamboo are still unpredictable. Given the potential of bamboo as a material, more and more scientists deal with this problem [5]. Chemical constituents of bamboo fibre are shown in Figure 1.
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China's water sustainability in the 21st century: a climate informed water risk assessment covering multi-sector water demands

China's water sustainability in the 21st century: a climate informed water risk assessment covering multi-sector water demands

annual values, to be of value for decision making. By estimating water needs over sea- sonal dry spells and across decades, and comparing it with actual rainfall, we find that majority of the areas, which contributes to the food security of the country face chronic stress. Most of these regions, like the North China Plain are also the most agriculturally productive regions. As questions loom over the success of the much acclaimed “South

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Analysis of multistoried braced steel space frame subjected to gravity and seismic loading.

Analysis of multistoried braced steel space frame subjected to gravity and seismic loading.

II. PROBLEM DEFINITION The structural modeling and analysis is done using STAAD-PRO software package to resist seismic load. Investigation is carried out for G+5 to G+11 storied steel structure. Three types of frames were analyzed namely bare frame, „Cross‟ bracing frame and „Single diagonal‟ bracing frame. typical rigid steel frame structure with and without bracing system containing three different model of similar plan are subjected to seismic load according to zone- III. a typical plan is shown in figure 1.1. Located on a medium soil strata are chosen for the study. Equivalent static analysis is performed on the models of the building considered in this study. Bracings are provided at the peripheral edges of the building. Column sizes and bracing sizes are changed according to loading condition and storey height. In this study the load combinations shall be accounted as per I.S 1893 (Part I)-2002.
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3D Stress intensity factor and T-stresses (T11 and T33)  formulations for a Compact Tension specimen

3D Stress intensity factor and T-stresses (T11 and T33) formulations for a Compact Tension specimen

tress tri-axiality at the crack-tip can alter crack-tip constraint and fracture toughness values of a material. This is the reason transferability of fracture toughness data estimated using laboratory test specimens to a full-scale cracked structure is an important issue in structural integrity assessment of engineering materials. In LEFM non-zero non- singular terms in the series expansion of three-dimensional stress field [1] referred as T-stresses (T 11 and T 33 ) can alter the

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Braz. Dent. J.  vol.23 número3

Braz. Dent. J. vol.23 número3

A etiologia do bruxismo é multifatorial, e fatores psicossociais têm sido apontados como notáveis potencializadores do risco para a ocorrência dessa parafunção. O presente estudo teve como objetivo avaliar o perfil comportamental de um grupo de crianças com bruxismo. Oitenta crianças de ambos os sexos, com idade entre 7 e 11 anos (idade media de 8,8 anos) foram recrutadas como possíveis participantes. Vinte e nove crianças, 18 do sexo masculino e 11 do feminino, cujos pais ou responsáveis relataram que as mesmas apresentavam rangimento dental freqüente (3 noites por semana) ou apertamento/rangimento dental em vigília, nos últimos 3 meses, foram selecionadas para o estudo. O diagnóstico de bruxismo foi estabelecido com base no relato dos pais ou responsáveis sobre os hábitos cotidianos das crianças e possíveis desordens do sistema estomatognático aliados à presença de sinais e sintomas tais como dor à palpação da musculatura mastigatória, hipertrofia do músculo masseter, facetas de desgaste, fratura de restaurações, impressões dentais na bochecha e lingual. Como parte da avaliação psicológica, a Escala Comportamental Infantil A2 de Rutter foi aplicada aos pais ou responsáveis (um por criança) e a Escala de Stress Infantil foi aplicada às crianças. Os dados foram tabelados e analisados descritivamente com base na freqüência de cada variável estudada. Vinte e quatro (82,76%) crianças necessitavam de intervenção psicológica ou psiquiátrica, sendo que 17 crianças apresentavam desordens neuróticas e 7 apresentavam desordens anti-sociais. Seis (20,70%) crianças apresentaram manifestações físicas e psicológicas de stress. Os resultados do presente trabalho sugerem que problemas comportamentais e potencialidades para o desenvolvimento de desequilíbrios emocionais podem ser fatores de risco para o bruxismo em crianças.
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Investigations to Model and Analyse the OHC Strength of Hybrid Composites

Investigations to Model and Analyse the OHC Strength of Hybrid Composites

OHC strength of all the laminates is plotted against width cor- rection factor (W/d). Fig. 3 shows the plots for various samples with different glass contents and orientations. From the graphs, the signiicance of width factor can be observed, the laminates sustain higher compressive loads for width factor greater than ive. This is attributed to the fact that as width factor reduces, the load bearing material reduces and hence smaller OHC strength. For width factors smaller than ive, the load carrying material is less than 25% resulting in lesser OHC strengths. The laminates show approximately nonlinear relation upto W/d=5 and thereaf- ter its approximately linear, this behaviour of the laminates reveal the fact that composites with load bearing material less than 25% exhibit higher stress concentration. The failure of these laminates is not only due to reduced load bearing area but also due to the difference in the Poisson’s ratio of the matrix and iber materi- als. Longitudinal compressive loading produces transverse tensile stresses within the matrix. These transverse tensile stresses can re- sult in longitudinal cracks developing parallel to the ibers within a weak matrix. In addition, a weak interface can also fail under these transverse tensile stresses. Voids within the matrix or at the interface will act as stress raisers and increase the chance of longi- tudinal cracking. Upon further loading, these cracks will grow and result in transverse rupture of the composite.
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Chemical analysis of potable water samples from selected suburbs of Accra, Ghana

Chemical analysis of potable water samples from selected suburbs of Accra, Ghana

The twelve suburbs selected in the Accra metropolis for this study was based on areas where potable water supply is inadequate and or non-existence. In such cases, individuals arrange for their water supply from vendors who normally supply in tanks. These suppliers either do not disclose their source of water or may give wrong information to their clients. The study area falls within the Greater Accra Metropolitan Area (GAMA). Accra, is located on latitude of 5.55 (5° 32' 60 N) and a longitude of 0.22 (0° 14' 60 W). The area is densely populated with population estimated to be around 3,909,764. The vegetation consists of the coastal savanna grassland. The climate is hot and humid and reflects a bimodal rainfall pattern with a mean annual rainfall of about 1,300 mm. The mean daily temperature is 26 °C with a range of 18 °C–35 °C. The relative humidity can be as high as 97% in the mornings of wet seasons and as low as 20% in the afternoon of the dry seasons. 2.2 Sampling
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Motivações, comportamento de viagem e benefícios obtidos dos turistas de bicicleta: uma análise do Mercado jovem

Motivações, comportamento de viagem e benefícios obtidos dos turistas de bicicleta: uma análise do Mercado jovem

The students of Portuguese universities are the population of this study. In 2015, there were 349,658 students enrolled in superior teaching in Portugal (Pordata, 2016). There are more female students (53.6%) than male students (46.4%). In order to analyze the use of bicycle by Portuguese university students during their tourism trips a questionnaire was carried out in 2016. The ques- tionnaire includes question related with the use of bicycle in tourism trips, the travel motivation re- lated with these trips, the travel behavior and the benefits obtained from the use of bicycle. An ex- tensive literature was used to formulate the ques- tions (e.g. Antonakos, 1994; Beanland, 2013; Ho, Liao, Huang & Chen, 2015; Hunt & Abraham, 2007; Lumsdon, 2001; Meschik, 2012; Oja, Vu- ori & Paronen, 1998; Ritchie, 1998; Ritchie et al., 2010). In order to improve the questionnaire a pre-test with twenty students from the first year of the tourism degree from University of Aveiro was carried out on March 16 th 2016. Based on the
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Stability analysis of a biological network

Stability analysis of a biological network

In case of systems biology it is very crucial impression of modeling the qualitative behavior of biological and biochemical networks where molecules are represented as nodes and the molecular interactions are so called edges. Due to scope and complicated behavior of these networks it is very important to discuss and study their dynamical behavior. An interaction dynamics can be used instead of an explicit mathematical description of these biological networks and computer simulations can be used to study the dynamical behavior of these complex biological networks. It is well known fact that dynamics is related to the study of changes with respect to time. For example in case of classical mechanics an apple falling to the ground, or the growth of the human population. Particularly, in case of systems biology dynamics is related to the changes in concentrations of molecules (or numbers) within a cell. Differential equations and difference equations are main tools for modeling these biological networks.
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J. Appl. Oral Sci.  vol.26

J. Appl. Oral Sci. vol.26

emphasized the correlation between stress and anxiety and exacerbation of lichen planus oral lesions. In this study, there was a relationship between the duration of the disease and the level of perceived stress, as well as the quality of life (especially the self-control domain). It seems that, the longer the patient needs to struggle with the underlying symptoms, the more likely he/she will develop a sense of loss of control. In severe cases, this may lead to acquired helplessness, causing patients to avoid medical treatment. Moreover, 30 out of 42 patients with OLP had concomitant skin,
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Verification of ESPI Stress Analysis by Means Of FEM

Verification of ESPI Stress Analysis by Means Of FEM

The main goal of this paper is verification of accuracy of ESPI strain sensor Dantec dynamics Q-100. ESPI is the digital holographic interferometry method for measuring small displacements and deformations. There is necessary to consider the isotropic material properties for stress calculations using the ESPI systems. All stress measurements were performed on simple shape specimens subjected to tension and bending. The experimental results obtained on the tensile testing machine Testometric will be compared with results from Finite element calculation.
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An Analysis Of The Difference In Gender Level Of Cassava Production And Access To Land In Abia State Nigeria

An Analysis Of The Difference In Gender Level Of Cassava Production And Access To Land In Abia State Nigeria

technique was employed in sample selection. In the first stage, the three agricultural zones in the state were purposively selected. Aba, Umuahia and Ohafia. In the second stage three local governments actively involved in agricultural production was purposively selected from each of the agricultural zone making it a total of nine blocks. While In the third stage two communities was randomly selected from each of the local government. Twelve respondents was randomly selected from two sampling group. six each for male and female giving twelve respondents from each cell. A total of 218 respondents was selected for the study. The research instrument used for this study was structured questionnaire and scheduled interview. The result of the objective of the study was analyzed using descriptive statistics such as frequency, percentage, and mean inferential which involves the use of Z-test analysis. The formula used to compute the mean used in this study is specified below. The mean was computed by multiplying the frequency (f) of the responses under each response category by assigned value and dividing the (∑) of the product by the (N) no of respondents to the particular indicator as shown:
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The Existence Of Leading Islands Securing And The Border Areas Unitary State Of Indonesia An Analysis In Law Perspective

The Existence Of Leading Islands Securing And The Border Areas Unitary State Of Indonesia An Analysis In Law Perspective

Abstract: The research was carried with the aim to discover the existence of securing the foremost islands and state border region of the Republic of Indonesia reviewed from a legal perspective, which is directly related to the existence of security and dispute resolution methods as well as the governance of the foremost islands and border region in Kalimantan which bordering Malaysia. This study was conducted in Nunukan district and the surrounding provinces of Kalimantan, in this research method that used is normative legal analysis data with juridical and qualitative descriptive approach. The results showed that the security of foremost islands and border region of law perspective in accordance with the Law No. 34 of 2004 regarding the Indonesian National Army has not been implemented to the fullest to realize the security of foremost islands and border region as the frontline of the Republic of Indonesia. The existence of leading islands securing and the border region of the Republic of Indonesia still contain many weaknesses in terms of both governance and security.
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Rev. esc. enferm. USP  vol.47 número5

Rev. esc. enferm. USP vol.47 número5

Therefore, an acceptable limit of normal values for salivary cortisol was established based on the da- ta collected. The saliva samples collected upon waking displayed an absolute range from 5 to 21.6 ng/mL ac- cording to the criteria established by the manufactu- rer (DBC®). Regarding the assessment of physiological stress, the salivary cortisol levels were presented as an area under the curve (AUC). The AUC calculation is used to obtain information about various measures re- lating to a specific time period.

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Modeling and Analysis of Queuing Systems in Banks A case study of Ghana Commercial Bank Ltd. Kumasi Main Branch

Modeling and Analysis of Queuing Systems in Banks A case study of Ghana Commercial Bank Ltd. Kumasi Main Branch

Abstract: Queues are common sight of many banks in Ghana. The obvious implication of customers waiting in long and winding queues could result to prolonged discomfort and economic cost to them; however increasing the service rate will require additional number of tellers which implies extra cost to management. This study therefore attempts to find the trade-off between minimizing the total economic cost (waiting cost and service cost) and the provision of a satisfactory and reasonably shortest possible time of service to customers, in order to assist management of the bank in deciding the optimal number of tellers needed. Data for this study was collected at the Ghana Commercial Bank Ltd, Kumasi Main Branch for one month through observations, interviews and by administering of questionnaire and was formulated as multi-server single line queuing model. The data was analyzed using TORA optimization Software as well as using descriptive method of analysis. The performance measures of different queuing systems were evaluated and analyzed. The results of the analysis showed using a five teller system was better than a four or a six-teller system in terms of average waiting time and thetotal economic cost, hence the study recommends that, the management should adopt a five teller model to reduce total economic costs and increase customer satisfaction.
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Mat. Res.  vol.12 número4

Mat. Res. vol.12 número4

The aim of this work was to study the influence of calcium carbonate nanoparticles in both tensile and impact mechanical properties of a polypropylene homopolymer. Four compositions of PP/CaCO 3 nanocomposites were prepared in a co-rotational twin screw extruder machine with calcium carbonate content of 3, 5, 7 and 10 wt. (%) The tests included SEM analyzes together with EDS analyzer and FTIR spectroscopy for calcium carbonate, tensile and impact tests for PP and the nanocomposites. The results showed an increase in PP elastic modulus and a little increase in yield stress. Brittle-to-ductile transition temperature was reduced and the impact resistance increased with the addition of nanoparticles. From the stress-strain curves we determined the occurrence of debonding process before yielding leading to stress softening. Debonding stress was determined from stress-strain curves corresponding to stress in 1% strain. We concluded that the tensile properties depend on the surface contact area of nanoparticles and on their dispersion. Finally we believe that the toughening was due to the formation of diffuse shear because of debonding process.
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Analysis and Treatment of a Nineteenth Century Portrait, Study of Artsorb® and a Proposal for a Microclimate Frame

Analysis and Treatment of a Nineteenth Century Portrait, Study of Artsorb® and a Proposal for a Microclimate Frame

Test 3 was done as an attempt to understand the reason chlorine was detected in the first Oddy test but not in the second. It may be that the absence of chlorine in Test 2 could lie in the different polishing methods used for the coupons or in the fact that the material was first pre-conditioned in a separate container. The glass bristle brush leaves a more reactive surface on the metal due to the striations left in the surface of the metal which increase the surface area available for reaction presumably leading to its greater response to pollutants or contaminants versus the surfaces polished with calcium carbonate. As for the pre-conditioning two theories are proposed: that the hygroscopic salt lithium chloride left the Artsorb® when it was exposed to 100% RH leaving a smaller amount in the Artsorb® sheets to react during the test, or that the lithium chloride, when exposed to such a high level of RH, was not available to react with the remaining materials due to its high affinity with the water. For that reason, in Test 3 the metal coupons were polished with a coarse polishing cloth to create striations and expose a more reactive surface, and the amount of water in the test bottles was varied to see how the salt would behave when saturated and not saturated with water. This test also included a variation in the temperature to see if that would have an influence on the salt reactivity. However, at the end of the test, none of the coupons exhibited a significant degree of corrosion and no chlorine was found in µ-EDXRF analysis (see Table VII.3 Appendix VII.3).
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