878 resultados para Grades de distorção


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This paper provides the experimental details of canning of tuna in oil. The species utilized in the experiments were the skipjack (Katsuwonus pelamis), yellowfin tuna (Neothunnus macropterus) and bigeye tuna Parathunnus obesus mebachi) ranging it weight from 2.5-82 kg. The method worked out is applicable to all species of different size grades.

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The beche-de-mer industry in India is a cent percent export oriented industry being confined to south east coast in Palk Bay and Gulf of Mannar in Tamil Nadu. Chemical quality of 180 trade samples of beche-de-mer of four sizes collected from the beche-de-mer curing centres of Ramanathapuram district was studied. Moisture ranged from 6.2 to 24.4% and sand content from 0.11 to 20.42% for all grades. Mean values of sand content are for grade 1=3.47%, grade 2=4.50%, grade 3=3.68%, grade 4=6.87%. Sodium chloride was almost constant for all grades at 5.7%. TVBN values ranged from 10 to 78.4 mg%. 44 laboratory samples of different grades were prepared following trade practice and examined for chemical quality. Mean moisture values are for grade 1=13.4%, grade 2=12.44%, grade 3=12.62%, grade 4=12.08% and mean values of sand are for grade 1=0.70%, grade 2=0.90%, grade 3=1.16%, grade 4=2.15%. The percentage of shrinkage of the animals ranged from 56% to 60% for dried beche-de-mer of 7.5 cm size and above.

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Commercial samples of frozen shrimp of different styles of presentation and size grades were tested for sensory, physical (cooked yield and pH) and biochemical characteristics (moisture, total nitrogen, water extractable nitrogen, nonprotein nitrogen, alpha amino nitrogen, total volatile nitrogen and trimethylamine nitrogen). The test results are compared and correlated. The order of preference of the samples were HL>PUD>P & D. There was significant correlation between sensory score of cooked sample and WEN, NPN and ∞ – NHsub(2)-N values. TVN and TMA-N did not exhibit any correlation with sensory score. It is inferred that in quality measurement of frozen shrimps of commerce the quantity of water soluble components and the total dry matter can be used to support the sensory test results.

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Over the last two or three years, the increasing costs of energy and worsening market conditions have focussed even greater attention within paper mills than before, on considering ways to improve efficiency and reduce the energy used in paper making. Arising from a multivariable understanding of paper machine operation, Advanced Process Control (APC) technology enables paper machine behaviour to be controlled in a more coherent way, using all the variables available for control. Furthermore, with the machine under better regulation and with more variables used in control, there is the opportunity to optimise machine operation, usually providing very striking multi-objective performance improvement benefits of a number of kinds. Traditional three term control technology does not offer this capability. The paper presents results from several different paper machine projects we have undertaken around the world. These projects have been aimed at improving machine stability, optimising chemicals usage and reducing energy use. On a brown paperboard machine in Australasia, APC has reduced specific steam usage by 10%, averaged across the grades; the controller has also provided a significant capacity to increase production. On a North American newsprint machine, the APC system has reduced steam usage by more than 10%, and it provides better control of colour and much improved wet end stability. The paper also outlines early results from two other performance improvement projects, each incorporating a different approach to reducing the energy used in paper making. The first of these two projects is focussed on optimising sheet drainage, aiming to present the dryer with a sheet having higher solids content than before. The second project aims to reduce specific steam usage by optimising the operation of the dryer hood.

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Papermaking is considered as an energy-intensive industry partly due to the fact that the machinery and procedures have been designed at the time when energy was both cheap and plentiful. A typical paper machine manufactures a variety of different products (grades) which impose variable per-unit raw material and energy costs to the mill. It is known that during a grade change operation the products are not market-worthy. Therefore, two different production regimes, i.e. steady state and grade transition can be recognised in papermaking practice. Among the costs associated with paper manufacture, the energy cost is 'more variable' due to (usually) day-to-day variations of the energy prices. Moreover, the production of a grade is often constrained by customer delivery time requirements. Given the above constraints and production modes, the product scheduling technique proposed in this paper aims at optimising the sequence of orders in a single machine so that the cost of production (mainly determined by the energy) is minimised. Simulation results obtained from a commercial board machine in the UK confirm the effectiveness of the proposed method. © 2011 IFAC.

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Demand for aluminum in final products has increased 30-fold since 1950 to 45 million tonnes per year, with forecasts predicting this exceptional growth to continue so that demand will reach 2-3 times today's levels by 2050. Aluminum production uses 3.5% of global electricity and causes 1% of global CO2 emissions, while meeting a 50% cut in emissions by 2050 against growing demand would require at least a 75% reduction in CO2 emissions per tonne of aluminum produced--a challenging prospect. In this paper we trace the global flows of aluminum from liquid metal to final products, revealing for the first time a complete map of the aluminum system and providing a basis for future study of the emissions abatement potential of material efficiency. The resulting Sankey diagram also draws attention to two key issues. First, around half of all liquid aluminum (~39 Mt) produced each year never reaches a final product, and a detailed discussion of these high yield losses shows significant opportunities for improvement. Second, aluminum recycling, which avoids the high energy costs and emissions of electrolysis, requires signification "dilution" (~ 8 Mt) and "cascade" (~ 6 Mt) flows of higher aluminum grades to make up for the shortfall in scrap supply and to obtain the desired alloy mix, increasing the energy required for recycling.

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The quasi-static and dynamic responses of laminated beams of equal areal mass, made from monolithic CFRP and Ultra high molecular weight Polyethylene (UHMWPE), have been measured. The end-clamped beams were impacted at mid-span by metal foam projectiles to simulate localised blast loading. The effect of clamping geometry on the response was investigated by comparing the response of beams bolted into the supports with the response of beams whose ends were wrapped around the supports. The effect of laminate shear strength upon the static and dynamic responses was investigated by testing two grades of each of the CFRP and UHMWPE beams: (i) CFRP beams with a cured matrix and uncured matrix, and (ii) UHMWPE laminates with matrices of two different shear strengths. Quasi-static stretch-bend tests indicated that the load carrying capacity of the UHWMPE beams exceeds that of the CFRP beams, increases with diminishing shear strength of matrix, and increases when the ends are wrapped rather than through-bolted. The dynamic deformation mode of the beams is qualitatively different from that observed in the quasi-static stretch-bend tests. In the dynamic case, travelling hinges emanate from the impact location and propagate towards the supports; the beams finally fail by tensile fibre fracture at the supports. The UHMWPE beams outperform the CFRP beams in terms of a lower mid-span deflection for a given impulse, and a higher failure impulse. Also, the maximum attainable impulse increases with decreasing shear strength for both the UHMWPE and CFRP beams. The ranking of the beams for load carrying capacity in the quasi-static stretch-bend tests is identical to that for failure impulse in the impact tests. Thus, the static tests can be used to gauge the relative dynamic performances of the beams. © 2013 Elsevier Ltd. All rights reserved.

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对黄土高原地区子午岭天然柴松(Pinus tabulaeformisf.shekannesis)林种群的结构和动态进行了研究。结果显示:柴松种群结构呈反J分布型,种群处于增长阶段;种群的密度随径级的增加而降低,种群密度与径级呈现出明显的负相关;4个函数(生存率函数、积累死亡率函数、死亡密度函数、危险率函数)估计值说明种群具有前期增长、后期稳定的特点,其存活曲线介于DeeveyⅡ型和DeeveyⅢ型之间;随时间推移,种群中树和大树数量逐渐增多,种群在20 a后开始大量进入成熟阶段。表明柴松在本研究区内生长更新良好,在无人为干扰条件下,柴松可通过自我调节能力而保持种群的稳定性。

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Dissolved inorganic carbon (DIC) account for more than 95% of total carbon in seawater, so it is necessary to make reliable and precise measurements of DIC to study marine carbon cycling. In order to establish a simple and speed method, an airproof device of gas extraction-absorption was designed. Finally a simple method was developed for the determination of DIC in seawater through a large mount of experiments. The determination procedure is as follows: 100 similar to 150 mL seawater was put into conical flask, then add 10% H3PO4, the DIC in seawater sample was dissolved to form CO2 gas and carried by pure N-2, then the CO2 gas was absorbed by two grades 0.1 mol/L NaOH solution. Finally the absorbed solution was titrated by HCl standard solution of 0.01000 mol/L with the end points detected with the indicator phenolphthalein and bromocresol green-methyl red mixture. The precision and accuracy of the method were satisfied. This method was used to analyse seawater samples from Jiaozhou bay in June, 2003. The result shows that the average DIC in surface seawater is 2066 mumol/L, DIC in bottom seawater is 2075 mumol/L inside bay, but the average DIC in surface seawater is 1949 mumol/L, DIC in bottom seawater is 2147 mumol/L outside bay.

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The study of regional crustal stability of active tectonic region basically includes analysis of recent activity of Earth's crust, single factor assessment, study of complexity, and comprehensive assessment of crust stability. In this thesis, some work are made as follows: · Based on abundant data from gravity field, aeromagnetic survey, magnetism, magnetotelluric deep sounding, remote sensing and geotectonic as well as earthquakes observed in recent years around this region and adjacent zones, we can get a through understanding about the structural features and activity of the earth's crust in Chuan-Dian region. The results from explosion earthquake and telluric electromagnetic sounding are consistent with the structural features of the crust manifested by the geophysical field. The data of deep geologic structures are important for us to work out a vivid three-dimensional model of the earth's crustal structure of the Jinsha River region. According to a synthesis, the author of this thesis proposes some indicators for dividing the faulted blocks. It can also be inferred that the movement of the Chuan-Dian faulted block, which is the relatively active part of southwestern China, is controlled by the boundary faults, and the intensive activity and deformation are concentrated along the boundaries of the block. · Mainly discussing respectively the mechanism and laws of active faults, earthquakes, and geological hazards activity, and their influences on the stability and security of engineering, also trying to probe into the way to assess the risk of single factor in this section. Especially with the method of fractal geometry, the thesis has discussed how to study the complexity of each factor. These geologic hazards which are distributed at the uppermost part of the crust in this region form a typical mountainous set of the active tectonic areas. The results of survey show that some slopes are liable- to -sliding with a weak layer of low shear strength. Occurrences of landslides are to a great extent related to local geological structures, in particular active faults. This is why numerous landslides have occurred simultaneously around the epicenter of a strong earthquake or the center of a strong rainfall, which are related to active faults. · The analysis of the crustal stability is based on a regional grid division, and a fuzzy comprehensive analysis method is used to determine the grade of the quality in each grid. The evaluation factors and their weights are taken from the results of the hierarchical analysis. The evaluation indexes consist of qualitative and quantitative ones. The qualitative ones can be quantified through the experts weighing system, while the quantitative ones can be obtained from statistical analysis. For quality grades, four levels are used: stable, essentially stable, sub-stable, and unstable. The results of the evaluation on Jinshajiang region demonstrate that the crustal stability become distinctly worse in the areas controlled by active deep faults. Therefore, detailed investigations on the active faulting and geologic hazards, include earthquake activity are especially necessary for those areas adjacent to the deep fault belts. On the bases of the data available and the survey results, we have made a preliminary assessment for the construction conditions and adaptability of every planned site in the middle or lower reaches of Jinsha River. Finally, the thesis prospected the vista of the study of crustal stability.

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An Approach to the Rehabilitation of Prelingually Deaf Children After Cochlear Implantation Zheng Xiujin(Medical Psychology) Directed by Professor Yin WenGang Abstract Objective: To sum up the acquirement rule of speech and language capability which is for the prelingually deaf children after cochlear implantation by listening and language rehabilitation training and to investigate the factors that affect rehabilitation speed. Method: Sixty-four children received a cochlear implant at the age of 2 to 5 years from 2001 to 2005. They begin to be trained under group pattern after switch on 1 month. The whole training program lasted more than 7 months; after that, according to the teacher’s plan the training program was to be continued at home. Result: The period is 108±7.7 days that they can pronounce correctly 50 percent of all of simple-finals and compound-finals, the period is 115.0±7.8 days that they begin auditory repeating, the period is 135.3±10.9 days that they can speech the first specific word independently and the period is 200.3±13.9 days that they can speak 70 words and come into tri-gamut-word and two-word sentence period. The patient that is the group at the age of 2-3 years can take part in normal kindergarten after switch on about 10 months. There are no significant differences in various grades of speech-language development with different age groups and so do with different sex groups. There are significant differences in various grade of speech-language development with various IQ group (P<0.01) and so do with using and not using hearing aids before implantation. Conclusion: From the research we find that the speech and language development sequence is the same level between the prelingually deaf children of 2 to 5 years who received cochlear implant after speech training and normal children and which are stages of uncomplicated sound production, continuous syllabic (babbling), speech sprout, single-word utterances and two-word utterances in proper order. The time is short significantly and the reason is that cognition capability is enhanced along with the increase of age. The intelligence is main factor that affect rehabilitation speed and the speed in the group of high IQ is faster than common IQ. It is not because of the dominance cognition of the senior group that makes the increasing of the rehabilitation, it even makes slowly. The reason of which is that the senior group are exposed the language environment too late to achieve speech and language development. So we should perform an operation and training early. The effectiveness of rehabilitation after cochlear implantation is improved by using hearing aids before implantation. The reason is auditory stimulate can be benefit of to deaf children. The rehabilitation speeds in the children at the age of 2 to 5 years have nothing to do with sex. Key words: cochlear implant; speech therapy; paediatric rehabilitation

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This study investigated the major characteristics of creative thinking development for the school children in Beijing with paper/pencil tests. The “Creative Thinking Test” was executed. The representative samples were two groups of students who came from the classes in 3rd-grade to 12th-grade of normal schools in Beijing. The classes were selected at random, one grade one class. One group is composed of 387 students (218 males, 169 females) in 1993, the other is composed of 420 students (181 males, 239 females) in 2006. According to the data analysis, the major characteristics and the changes over the 13 years of the development of creative thinking for student were explored and discussed. 1) The development trends of three types of creative thinking were all flexuous increase with grade moving up. The mean score of elementary school students was the lowest. And scores of junior high school students and senior high school students were significant higher than elementary school students’. 2) The most rapid increase occurred from the 5th grade to 6th grade. 3) Slumps occurred in the 7th grade in PNE curve and also in the 9th and 12th grades in TPC curves. There was no slump in FGA curve. 4) The girl’s scores in PNE and TPC tests were significant better than boys’. No obvious gender difference was found in FGA test. 5) The scores of three creative thinking tests in 2006 were all better than those in 1993. Separately, the scores of FGA and TPC tests in 2006 were significant higher than the corresponding scores in 1993, and no significant difference was found in two PNE tests. 6) There was no significant difference in the maximum scores of the three creative thinking tests between 2006 and 1993. 7) The most rapid developing period of three types of creative thinking in 2006 were the 5th grade and the 6th grade. The same period in 1993 was from the 7th grade to 9th grade. 8) In 1993, there is no significant gender difference for each creative thinking test. In 2006, PNE and TPC results had remarkable gender difference that girls were higher than boys. No significant gender difference was found in FGA tests.

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The aim of this research is to explore the relationships between school avoidance tendency and school stressors, stress response, social support, coping style of secondary school students. Three studies were carried out. School avoidance tendency scale, mental health scale, coping style scale of secondary school students from Japan were revised in the first research. In the second research, the difference in gender, cities, grades of five variables were discussed. In the third research, the relationships of five variables were discussed. A total of 883 students from grade one of middle school to grade 3 of high school in Beijing, Taiyuan and Wulanchabu, completed three scales. Analysis showed that: 1. The main effects of city, gender, and grade were present significantly on School avoidance tendency, and the inter-effects were not significant. The differences were significant between three grades of middle schools, and not significant between three grades of high schools. The high school students were significant than middle school students on school avoidance tendency. 2. The main effect of city was not significant, but gender, and grade were present significantly on stressor, and the inter-effects were not significant. The most stressor was study one, than the relationship stressor from teachers. The relationship stressor from friends was at least. 3. The main effects of city and grade were present significantly on stress responses, but the main effect of gender was not significant, and the inter-effect was not significant. The most stress response was the physical response. 4. The main effects of city and gender, the inter-effect were not present significantly on social supports. The main effect of grade was present significantly. The most social support was from mother, than from friends, father, and the teachers. 5. The differences between cites on coping styles were not significant. Positive coping style was used mostly, than the style of help requirement, cognitive coping style. 6. Stressor and stress responses had significant positive predictive role on school avoidance tendency. Social supports had negative predictive role. Social supports had not moderator role between stressor, stress responses and schools avoidance tendency. Stress responses had a part of mediator between stressor and school avoidance tendency. 7. In the coping styles, positive coping style and help requirement style had negative predictive role, but cognitive coping style had positive predictive role on school avoidance tendency. Coping styles had negative predictive role. Coping styles had not moderator role between stressor, stress responses and school avoidance tendency.

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Achievement motive is human’s social motive. In some sense, one’s all-life achievements are decided by his/her achievement motive. By which we can conclude that achievement motive has close connection with individual emotional experience. People pursuing success experience more positive emotion and less negative one, and have good behavioral adaptability. This study aims at explore the relation between achievement motive and behavior problems in the secondary vocational education schools through questionaries (the achievement motivation scale, UCLA Loneliness Scale,State-Trait Anxiety Inventory,Center for Epidemiologic Studies depression Scale and middle school students'behavior questionnaire). There were 1005 students whose age ranged from 14to21 years completed the questionnaires. The main conclusions of this thesis are as follows: (1) Achievement motive of student in the secondary vocational education schools is significantly lower than that of students in the senior high school. (2) Students in the secondary vocational education schools show more obvious emotion and Externalizing behavior problems than those of the senior high schools. (3) Students’ motivation for pursuing success in the secondary vocational education schools has negative correlation with emotion and Externalizing behavior problem, while the motivation for avoiding failure has positive correlation with the emotion and Externalizing behavior problem. Achievement motivation has negative correlation with emotion and Externalizing behavior problem. (4) Students’ achievement motivation shows obvious gender difference in the secondary vocational education schools. The avoiding failure element shows upward trend with the grades increasing and the difference is obvious. While the students’ achievement motive in the secondary vocational education schools shows significantly downward trend with the grades increasing. Whether holding a post at school has influence on the students’ achievement motivation, and the difference is significant. (5) Students’ Externalizing behavior problem in the secondary vocational education schools shows obvious gender difference. Whether holding a post at school has influence on the students’ Externalizing behavior problem, and depression and loneliness, and the difference is significant. Key words: Students in the Secondary Vocational Education Schools, Achievement Motivation, Behavior Problem, Emotion Problem, Externalizing Behavior Problem (Note: In this study, the behavior problems include not only the externalizing behavior problems, but also emotion problems.)

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In the period of college, an individual matures rapidly in all aspects. College engineering students are the important parts of undergraduates. The state of an individual’s mental health may affect and even decide his future life and work. The level of the student’s self-concept and the kind of coping styles the students adopt are directly related to their mental health. So, it is significant to study the psychological stress, coping and self-concept of college engineering students for the mental health education and research of college engineering students. Based on overviews of former research, with the China College Student Psychological Stress Scale, the Coping Styles Scale and the Tennessee Self-Concept Scale, 559 college engineering students were investigated to explore the characteristics of and the relationship between the psychological stress, coping styles and self-concept of college engineering students. The results showed: 1. The stresses of learning, living and daily hassles were the main psychological stresses of college engineering students. There were significant differences in psychological stress between students from the countryside and those from urban areas, between needy students and non-needy students, between single-parent students and non-single-parent students, among students from different grades, with different academic achievements and of different postgraduate targets, between student party members and non-party members, between student cadres and non-cadres. However, there were no significant differences between male and female, between those from single-child families and from multiple-child families. 2. The coping styles of solving problem, seeking help and rationalization were the main coping styles of college engineering students. There were significant differences in the coping styles between needy students and non-needy students, among students from different grades, with different academic achievements and of different postgraduate targets, between student party members and non-party members, between student cadres and non-cadres. However, there were no significant differences between students from the countryside and from urban areas, between male and female, between single-parent students and non-single-parent students, between those from single-child families and from multiple-child families. 3. The self-concept of college engineering students was positive in general. There were significant differences in self-concept between students from the countryside and those from urban areas, between male and female, between needy students and non-needy students, between single-parent students and non-single-parent students, among students from different grades, with different academic achievements and of different postgraduate targets, between student party members and non-party members, between student cadres and non-cadres. However, there were no significant differences between those from single-child families and from multiple-child families. 4. The psychological stress had significantly negative correlation to the immature coping styles, and had partial correlation to the mature coping styles. Coping style has significant predictability on psychological stress. 5. The positive factors of the self-concept had significantly negative correlation to psychological stress, but self-criticism had positive correlation to psychological stress. There are significant differences between high self-concept students and low self-concept students for psychological stress. Self-concept has significant predictability on psychological stress. 6. The positive factors of the self-concept had significantly negative correlation to the coping styles of self-blame, illusion, avoidance, and rationalization, but had significantly positive correlation to the coping style of solving problem and seeking help. Self-criticism had significantly negative correlation to the coping styles of self-blame, illusion, avoidance, and rationalization. There are significant differences between high self-concept students and low self-concept students for coping styles. Self-concept has significant predictability on coping styles. 7. The self-concept of college engineering students had an effect on psychological stress by coping styles. However, the effect by the immature coping styles was higher than that to the mental health directly, and the effect by the mature and mixed coping styles was slighter than that to the mental health directly. According to the results, improving the college engineering students’ self-concept level and establishing right self-concept, developing the middle school student’ active coping styles and overcoming the negative coping styles are essential and important to the college engineering students’ mental health and provide useful clues for the psychological education of the college engineering students.