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31.
Sensors play a crucial role in the future of dairy farming. Modern dairy farms today are equipped with many different sensors for milk yield, body weight, activity, and even milk composition. The challenge, however, is to translate signals from these sensors into relevant information for the farmer. Because the measured values for an individual cow show nonstationary behavior, the concepts of statistical process control, which are commonly used in industry, cannot be used directly. The synergistic control concept overcomes this problem by on-line (real-time) modeling of the process and application of statistical process control to the residuals between the measured and modeled values. In this study, the synergistic control concept was developed and tested for early detection of anomalies in dairy cows based on detection of shifts in milk yield. Compared with the combination of visual observation and milk conductivity measurements, the developed strategy had a sensitivity of 63% for detecting clinical mastitis. Consequently, this technique could have added value on many farms, as it extracts practical information out of inexpensive data that are already available. As it can be easily extended to other measured parameters, the technique shows potential for early detection of other nutrition and health problems. 相似文献
32.
Zero Risk Does Not Exist: Lessons Learned from Microbial Risk Assessment Related to Use of Water and Safety of Fresh Produce 下载免费PDF全文
Ann De Keuckelaere Liesbeth Jacxsens Philip Amoah Gertjan Medema Peter McClure Lee‐Ann Jaykus Mieke Uyttendaele 《Comprehensive Reviews in Food Science and Food Safety》2015,14(4):387-410
Risk assessments related to use of water and safety of fresh produce originate from both water and food microbiology studies. Although the set‐up and methodology of risk assessment in these 2 disciplines may differ, analysis of the current literature reveals some common outcomes. Most of these studies from the water perspective focus on enteric virus risks, largely because of their anticipated high concentrations in untreated wastewater and their resistance to common wastewater treatments. Risk assessment studies from the food perspective, instead, focus mainly on bacterial pathogens such as Salmonella and pathogenic Escherichia coli. Few site‐specific data points were available for most of these microbial risk assessments, meaning that many assumptions were necessary, which are repeated in many studies. Specific parameters lacking hard data included rates of pathogen transfer from irrigation water to crops, pathogen penetration, and survival in or on food crops. Data on these factors have been investigated over the last decade and this should improve the reliability of future microbial risk estimates. However, the sheer number of different foodstuffs and pathogens, combined with water sources and irrigation practices, means that developing risk models that can span the breadth of fresh produce safety will be a considerable challenge. The new approach using microbial risk assessment is objective and evidence‐based and leads to more flexibility and enables more tailored risk management practices and guidelines. Drawbacks are, however, capacity and knowledge to perform the microbial risk assessment and the need for data and preferably data of the specific region. 相似文献
33.
Gemma Corbalan Liesbeth KesterJeroen J.G. van Merriënboer 《Computers in human behavior》2011,27(1):76-81
Surface task features are more salient than structural task features and thus easier to recognize for novices. It is predicted that the more salient the task features the better learners can choose personally relevant and varied tasks, which enhances learning transfer. To investigate this prediction, a 2 × 2 factorial experiment with 72 participants studied the effects of control over tasks that differ in their surface features (learner, program) and in their structural features (learner, program). Learner control over the selection of tasks with salient surface features enables learners to select personally relevant and varied tasks. This is believed to yield higher effectiveness (i.e., higher near and far transfer test performance) as well as higher efficiency (i.e., higher transfer test performance combined with lower associated mental effort). Learner control over the selection of tasks with non-salient structural features does not enable learners to select personally relevant and varied tasks and is therefore not expected to yield beneficial effects on learning. The results show positive effects of learner control over the selection of tasks with salient surface features for efficiency on the far transfer test but not for effectiveness. Theoretical and practical implications are discussed. 相似文献
34.
Mercken Liesbeth; Candel Math; Willems Paul; de Vries Hein 《Canadian Metallurgical Quarterly》2009,28(1):73
Objective: This article examined the contribution of selection and influence processes in smoking behavior similarity among friends, and changes in these processes during early and mid adolescence. Design: Data from 1886 Dutch high school students in the control group of the European Smoking prevention Framework Approach (ESFA) study were used. Changes in selection and influence were examined during three successive waves using structural equation modeling. Main Outcome Measures: Smoking behavior of adolescents, best friends, parents, and siblings. Results: Most support was found for selection of reciprocal (pwave1,2,3 wave1,2 wave3 = 0.25), although these effects decreased over time. Support for influence was only found among nonreciprocal (desired) friends during the last wave (pwave3 wave2 wave1,3 > 0.05) and siblings (pwave1,2 wave3 = 0.16), but influence diminished over time. Conclusion: Smoking-based selection processes decreased over time while the influence of friends increased. Smoking prevention programs should focus on the structure of peer environments besides promoting social influence skills. During early adolescence parents and siblings should be targeted, while during mid adolescence, the focus should shift toward the adolescents and their dynamic peer environment. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
35.
Liesbeth Groenesteijn Suzanne Hiemstra-van Mastrigt Cedric Gallais Merle Blok Lottie Kuijt-Evers Peter Vink 《Ergonomics》2014,57(8):1154-1165
Working in the train is a part of new ways of working. However, the ideal working position is unknown. Moreover, the ideal position for leisure and relaxing is also unknown. This article defines what activities train passengers mainly perform and which corresponding postures are seen. Based on the observations on actual train rides, four main activities could be identified: Reading, Staring/sleeping, Talking and Working on laptop. Working on laptop was the activity with the longest duration and talking had the shortest duration. Associated with these four activities, a top eight of different postures were observed. Except for headrest comfort, comfort scores were not significantly different between activities. The top eight corresponding postures combined with comfort scores showed that per activity different postures were observed and the comfort scores varied in relation to the combination of posture and activity. Nearly for all activities, the majority of passengers preferred adjustability options to fit the seat to the performed activity. 相似文献
36.
Vicky Jasson Liesbeth Jacxsens Pieternel Luning Andreja Rajkovic Mieke Uyttendaele 《Food microbiology》2010
This study provides an overview and criteria for the selection of a method, other than the reference method, for microbial analysis of foods. In a first part an overview of the general characteristics of rapid methods available, both for enumeration and detection, is given with reference to relevant bibliography. Perspectives on future development and the potential of the rapid method for routine application in food diagnostics are discussed. As various alternative “rapid” methods in different formats are available on the market, it can be very difficult for a food business operator or for a control authority to select the most appropriate method which fits its purpose. Validation of a method by a third party, according to international accepted protocol based upon ISO 16140, may increase the confidence in the performance of a method. A list of at the moment validated methods for enumeration of both utility indicators (aerobic plate count) and hygiene indicators (Enterobacteriaceae, Escherichia coli, coagulase positive Staphylococcus) as well as for detection of the four major pathogens (Salmonella spp., Listeria monocytogenes, E. coli O157 and Campylobacter spp.) is included with reference to relevant websites to check for updates. In a second part of this study, selection criteria are introduced to underpin the choice of the appropriate method(s) for a defined application. The selection criteria link the definition of the context in which the user of the method functions – and thus the prospective use of the microbial test results – with the technical information on the method and its operational requirements and sustainability. The selection criteria can help the end user of the method to obtain a systematic insight into all relevant factors to be taken into account for selection of a method for microbial analysis. 相似文献
37.
Mertens Evelien Mullie Patrick Deforche Benedicte Lefevre Johan Charlier Ruben Huybrechts Inge Clarys Peter 《Nutrition journal》2014,13(1):1-8
The portion size of food is a determinant of energy intake, linking with obese traits. A healthy plate for portion control has recently been made in a Japanese style. The aim of the current study was to assess the efficacy of a lifestyle intervention program using the Japanese-style healthy plate on weight reduction in overweight and obese diabetic Japanese subjects. We randomized overweight and obese diabetic subjects (n = 19, 10 women) into an intervention group including educational classes on lifestyle modification incorporating the healthy plate (n = 10) or a waiting-list control group (n = 9). The intervention period was three months, and the educational classes using the healthy plate were conducted monthly in a group session for the intervention group. The body weight, blood glycemic and metabolic measures, and psychosocial variables were measured at the baseline and after the 3-month intervention in both groups. The impression of the intervention was interviewed using a structured questionnaire. There was one drop-out in the control group. No adverse events were reported in the groups. Subjects in the intervention group had a greater weight change from baseline to the end of the 3-month intervention period (-3.7 +/- 2.5 [SD] kg in the intervention group vs. -0.1 +/- 1.4 kg in the control group, P = 0.002). Most subjects recorded that the use of a healthy plate could be recommended to other people. The lifestyle intervention program using the Japanese-style healthy plate, which was developed for portion control, may effectively reduce body weight in overweight and obese diabetic subjects in Japan. Further studies are needed to establish the efficacy of this methodology on weight management. 相似文献
38.
Krishna Vyncke Inge Huybrechts Myriam Van Winckel Magdalena Cuenca Garcia Idoia Labayen Frederic Gottrand Kurt Widhalm Catherine Leclercq Lars Libuda Yannis Manios Michael Sjostrom Denes Molnar Luis A. Moreno Marcela Gonzalez-Gross André Spinneker Fatima Perez de Heredia Maria Plada Stefaan De Henauw 《Lipids》2014,49(9):881-893
The present study aimed to assess the correlation between food and fatty acid (FA) intake and the serum phospholipid (PL) FA status in European adolescents and explored the percentage of variation in serum PL FA that could be attributed to dietary habits. Participants included 528 adolescents recruited in the HELENA Study. Dietary intake was assessed by two, self-administered, non-consecutive 24-h recalls. PL FA concentrations were measured in fasting venous serum samples. Reduced rank regressions were applied to examine the combined effect of food intakes. Results indicated that the variance in serum PL FA in adolescents, that could be explained by diet varied from 7.0 % for MUFA to 14.2 % for n-3FA. The variance in the long-chain n-3FA was mainly explained by fish intake but also by coffee and tea consumption. In conclusion this study indicated that dietary intake influences the serum PL FA status to a limited amount but that also other factors interfere. However, dietary intake is important as it is among those factors that could be modified. Furthermore, the results suggest that the overall dietary habits should be considered instead of only the consumption of single foods or nutrients, as the medium of the food or concomitant intake of foods and nutrients might interact and as such influence absorption or metabolism. 相似文献
39.
Geert Hellings Andriy HikavyyJerome Mitard Liesbeth WittersBrahim Benbakhti AliReza Alian Niamh WaldronHugo Bender Geert Eneman Raymond Krom Andreas Schulze Wilfried Vandervorst Roger LooMarc Heyns Marc MeurisThomas Hoffmann Kristin De Meyer 《Thin solid films》2012,520(8):3326-3331
The Implant-Free Quantum Well Field-Effect Transistor (FET) offers enhanced scalability in a planar architecture through the integration of heterostructures. The Implant-Free architecture fully utilizes the band offsets between different materials, whereby charge carriers are effectively confined to a thin channel layer. This prevents sub-surface source/drain leakage observed in classical bulk Metal-Oxide-Semiconductor FETs at small gate lengths. An investigation of the VT-tuning capabilities of this technology reveals sensitivity to both well doping and bulk voltage. 相似文献
40.