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141.
The issue-tracking systems used by software projects contain issues, bugs, or tickets written by a wide variety of bug reporters, with different levels of training and knowledge about the system under development. Typically, reporters lack the skills and/or time to search the issue-tracking system for similar issues already reported. As a result, many reports end up referring to the same issue, which effectively makes the bug-report triaging process time consuming and error prone. Many researchers have approached the bug-deduplication problem using off-the-shelf information-retrieval (IR) tools. In this work, we extend the state of the art by investigating how contextual information about software-quality attributes, software-architecture terms, and system-development topics can be exploited to improve bug deduplication. We demonstrate the effectiveness of our contextual bug-deduplication method at ranking duplicates on the bug repositories of the Android, Eclipse, Mozilla, and OpenOffice software systems. Based on this experience, we conclude that taking into account domain-specific context can improve IR methods for bug deduplication. 相似文献
142.
143.
Eleni Georgiou Marios D. Dikaiakos Athena Stassopoulou 《Journal of Network and Computer Applications》2008,31(4):966-985
The main purpose of most spam e-mail messages distributed on Internet today is to entice recipients into visiting World Wide Web pages that are advertised through spam. In essence, e-mail spamming is a campaign that advertises URL addresses at a massive scale and at minimum cost for the advertisers and those advertised. Nevertheless, the characteristics of URL addresses and of web sites advertised through spam have not been studied extensively. In this paper, we investigate the properties of URL-dissemination through spam e-mail, and the characteristics of URL addresses disseminated through spam. We conclude that spammers advertise URL addresses non-repetitively and that spam-advertised URLs are short-lived, elusive, and therefore hard to detect and filter. We also observe that reputable URL addresses are sometimes used as decoys against e-mail users and spam filters. These observations can be valuable for the configuration of spam filters and in order to drive the development of new techniques to fight spam. 相似文献
144.
ABSTRACTDigitizing buildings via building information modelling (BIM) is increasingly gaining traction in the architecture, engineering and construction (AEC) sector. The plethora of BIM-based technologies affects both inter- and intra-organizational relations. Structured inter-organizational networks across tiers, such as supply chain (SC) partnerships were used to examine how BIM affects these changing relations across and within firms’ boundaries. Empirical explorations around the interplay between BIM and SC partnering – as a proxy for supply chain management (SCM) philosophy – were deployed to assess their contribution to SC integration, and to investigate the functions of key actors in AEC. One young and one long-standing SC partnership were studied, and it was observed that the contractual arrangements had to be complemented by well-defined BIM scope, and communications across multiple tiers to built trust and support collaboration in the network. There were two types of BIM-enabled SC partnering: with emphasis on either transactions or relations, the former being merely operational whereas the latter strategic. These inter-organizational orientations of BIM-enabled SC partnering outlined further intra-organizational conditions for integration regarding functional division, business models and services offered. The study carries implications for BIM and SCM researchers, policy-makers and practitioners, and proposes strategies for SC integration by aligning intra- with inter-organizational relations. 相似文献
145.
146.
Antonio J. Del Águila-Carrasco Daniel Monsálvez-Romín Eleni Papadatou 《Contact lens & anterior eye》2017,40(5):346-350
Purpose
To present a methodology for evaluating the optical quality of rotationally symmetrical contact lenses (CLs) from a single power profile.Methods
Simulated rotationally symmetrical power profiles corresponding to different CLs designs (monofocal, two-zone center-near bifocal, and four-zone center-distance bifocal) were used to calculate the wavefront error profile by means of numerical integration. Then, each lens wavefront error profile was spun around the center to obtain the lens wavefront error surface. From the surface, monochromatic optical transfer functions (OTF), simulated images and the visual Strehl ratio based on the OTF (VSOTF) were obtained for different distances and pupil sizes (3 and 5.5 mm) after performing a through-focus.Results
VSOTF variations, taking into account both vergence and pupil size, were presented for the three CLs designs. The monofocal design showed excellent optical quality only for far vision, whereas the bifocal designs exhibited good optical quality for far and near vision. Modulation transfer function (MTF) from each lens design, pupil size, and work distance agreed with the previous results.Conclusions
The methodology presented here allows for a rapid and thorough assessment of the optical quality of rotationally symmetrical CLs by means of optical quality metrics, with a special interest in simultaneous image contact lenses. This methodology may be useful for choosing the most suitable lens for each subject’s visual demands. 相似文献147.
Literature study on the rate and mechanism of carbonation of lime in mortars / Literaturstudie über Mechanismus und Grad der Karbonatisierung von Kalkhydrat im Mörtel 下载免费PDF全文
Eleni Despotou Dr. Aurela Shtiza Dr. Thomas Schlegel Frederik Verhelst Ing. 《Mauerwerk》2016,20(2):124-137
The hardening kinetics of a lime based mortar is based on the uptake of carbon dioxide from the ambient air. The presence of watervapour is required in order to enable the reaction between the CO2 and the lime (calcium hydroxide). Via this reaction the hardening of air lime is net uptaker of CO2. An extensive literature study was made on the fundamentals of the carbonation process in mortars with different compositions. The results of the study indicate that carbonation ranges from 80 % up to 90 %. It is clear that the mechanism and the kinetics of the carbonation depend strongly on the mineralogy, texture of mortars, type of additive used, the lime use for the mortar, the width of the walls, thickness of the mortar (less carbonation when mortar depth increases) as well as the timeframe allowing for the carbonation process to take place. Under natural conditions, actual building practice and depending on the thickness of the mortar/plaster, carbonation takes between a few weeks and several years. The results of this study were used for the environmental footprint study in order to calculate the capture of CO2 that occurs progressively during the hardening of a building materials containing lime. 相似文献
148.
Acquired reactive perforating collagenosis and pseudoporphyric bullous dermatosis in a hemodialysis patient 下载免费PDF全文
Nikos Sabanis Eleni Paschou Eleni Gavriilaki Asterios Kalaitzoglou Dimitrios Papanikolaou Sotiris Vasileiou Ioannis Amplianitis 《Hemodialysis international. International Symposium on Home Hemodialysis》2016,20(3):E14-E18
Hemodialysis patients present with a broad spectrum of specific and nonspecific skin disorders, which rarely coexist. We report an exceptional case of a hemodialysis patient that developed acquired reactive perforating collagenosis and pseudoporphyric bullous dermatosis on the basis of common skin disorders which include hyperpigmentation, pruritus, xerosis cutis, and Linsday's nails. Interestingly, our patient presented with two unusual but distinctive cutaneous dermopathies on the background of other commonly seen skin alterations. The patient was successfully treated with allopurinol and N‐acetylcysteine. Avoidance of potentially triggering factors such as alcohol, sunlight exposure and certain medication was recommended. Thus, increasing clinical awareness, assiduous investigation and early treatment of skin disorders are required to improve the prognosis and quality of life in this patient population. 相似文献
149.
Konstantinos Barlas Eleni Berki Petros Stefaneas George Koletsos 《Innovations in Systems and Software Engineering》2017,13(1):51-66
Open standardization seems to be very popular among software developers as it simplifies the standard’s adoption by the software engineering. Formal specification methods, while very promising, are being adopted slowly as the industry seems to have little motivation to move into this territory. In this paper the authors present (1) the idea of applying formal specification techniques to open standards’ specifications, and (2) an example of a formal specification of the Rich Site Summary (RSS) v2.0 open standard. The authors provide evidence for the advantages of the open standards formal specification over natural language documentations: formal specifications are more concise, less ambiguous, more complete with respect to the original documentation and, when using certain kinds of specification languages, executable and reusable as they support module inheritance. The merging of formal specification methods and open standards allows (1) a more concrete standard design; (2) an improved understanding of the environment under design; (3) an enforced certain level of precision into the specification, and also (4) provides software engineers with extended property checking/verification capabilities, especially if they opt to use any algebraic specification language. The authors showcase how the RSS standard can be formally specified using an algebraic specification language and demonstrate how can that be beneficial. 相似文献
150.
Christina Anniva Despina Grigoriadou Eleni Psomiadou Maria Z. Tsimidou 《Journal of the American Oil Chemists' Society》2006,83(4):371-375
In previous studies we reported the presence of compounds with spectral characteristics similar to pheophytin α (Pheo α),
which often accompany the Pheo α peak in the chromatographic profile of virgin olive oils (VOO) at 410 nm under normal-phase
HPLC conditions. The occurrence and levels of these compounds were found to be affected by storage conditions of the oil samples.
In the present study we investigated whether the major Pheo a degradation products, identified as pyropheophytin α (coeluting
with the respective epimer) and 132-OH-pheophytin α, could be used as estimates of VOO history. The content of Pheo α and its degradation products was determined
for a great number of authentic olive oil samples of unknown history. Results are discussed in comparison with other quality
indices (e.g., antioxidant content) when necessary. High amounts of the pyro form (20–30% of total pheophytins) were related
to thermal abuse or lengthy storage. The presence of allomers indicated oxygen availability. The levels of these products,
0–20% of the total pheophytin content for 62% of the samples, seemed to be influenced by the presence of pro- and antioxidants.
When low levels of Pheo α are not accompanied by other degradation products, light exposure for a certain period of storage
can be assumed. 相似文献