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51.
In this article, alternative approaches to digital keyboard instrument synthesis are looked into. Physics-based sound synthesis, which aims at generating natural-sounding musical instrument tones algorithmically without using a large sample database, is a promising approach. It would provide high-quality music synthesis to systems that cannot afford a large memory, such as mobile phones and portable electronic games. The realistic parametric synthesis of musical instrument sounds is still a challenge, but physical modeling techniques introduced during the last few decades can help to solve it. Recently, the first commercial products have been introduced, for example, by Pianoteq. Three keyboard instruments, the clavichord, the harpsichord, and the grand piano, are focused on here. The sound production principles and acoustics of these instruments are first discussed. Then, the previous parametric synthesis algorithms developed for these instruments are reviewed. The remaining part of this article concentrates on new signal processing methods for parametric synthesis of the piano 相似文献
52.
M Kajanti C Blomqvist H Lehtonen M Kouri T Wiklund LR Holsti 《Canadian Metallurgical Quarterly》1997,39(4):837-840
PURPOSE: To study the feasibility of a dose-escalated accelerated hyperfractionation schedule for patients with advanced head and neck cancer. MATERIALS AND METHODS: Twenty-nine previously untreated patients with advanced squamous cell carcinoma were treated with the following biweekly dose-escalated accelerated hyperfraction schedule: during the first 2 weeks 1.2 Gy twice a daily (bid) up to 24 Gy, thereafter during the next following 2 weeks 1.4 Gy bid to 28 Gy in 20 fractions, and thereafter 22.4 Gy in 1.6 Gy bid fractions during 1 1/2 weeks. Thus, the the total dose was 74.4 Gy in 54 fractions given in 5 1/2 weeks. RESULTS: The planned total dose was given within the planned time to 19 (66%) patients. For seven patients the treatment time was prolonged with 1 to 6 days because of department closure for holidays or machine-down days, and in three cases the treatment time was prolonged more than 8 weeks. When the tumor responses were evaluated at 3 months after given radiotherapy, 27 (93%) patients showed complete tumor clearance, 1 patient had a recidual focus, and 1 patient showed progressive disease. The ultimate 1-, 2-, and 3-year local control rates were: 87, 71, and 60%. Four patients had a salvage laryngectomy. The 1-, 2-, and 3-year survival rates for all patients were as follows: 96, 81, and 73%. All patients developed confluent mucositis, 15 patients were hospitalized for nutritional support, and 11 patients had moist desquamation. However, all acute reactions healed completely, and no serious late complications were observed. CONCLUSIONS: This is a safe and effective treatment schedule for patients with advanced head and neck cancer. 相似文献
53.
Product authentication is needed to detect counterfeit products and to prevent them from entering the distribution channels of genuine products. Security is a critical property of product authentication systems. In this paper, we study trust and security in RFID-based product authentication systems. We first present a formal definition for product authentication process and then derive the general chain of trust as well as functional and nonfunctional security requirements for product authentication. Most of the scientific literature that covers the topic focuses on cryptographic tag authentication only. This paper, however, provides a broader view including also other known approaches, most notably location-based authentication. To derive the functional security requirements, we employ the concept of misuse cases that extends the use case paradigm well known in the field of requirements engineering. We argue that the level of security of any RFID-based product authentication application is determined by how it fulfills the derived set of functional and nonfunctional requirements. The security of different RFID-based product authentication approaches is analyzed. To study how RFID supports secure product authentication in practice, we investigate how the current EPC standards conform to the functional security requirements of product authentication and show how the unaddressed requirements could be fulfilled. The benefits of implementing a service that detects the cloned tags in the level of the network's core services are identified. 相似文献
54.
K Riento J J?ntti S Jansson S Hielm E Lehtonen C Ehnholm S Ker?nen VM Olkkonen 《Canadian Metallurgical Quarterly》1996,239(3):638-646
Sec1-related proteins are involved in docking and fusion of transport vesicles in eukaryotic cells. Here we report the cloning and molecular characterization of a Sec1-related protein expressed in the MDCK epithelial cell line. This protein represents a canine counterpart of the murine Munc-18-2/Munc-18b/muSec1 protein, displays 93% amino acid identity with these proteins, has a similar tissue mRNA expression pattern, and associates in vitro with syntaxins 1A, 2, and 3. In situ hybridization analysis of embryonic mouse tissues revealed prominent expression of the munc-18-2 mRNA in the epithelia of several tissues. Cell-fractionation studies demonstrated that the majority of Munc-18-2 is membrane associated. Most of the protein is washed off the membranes by sodium carbonate, pH 11.5. However, the protein is poorly solubilized by detergent treatment. The Munc-18-2 protein was localized, by immunofluorescence microscopy, to the plasma membrane of MDCK cells, and is apically distributed in the epithelial cells of mouse tissues. When overexpressed in COS-1 cells, the protein appeared to be largely cytosolic. However, upon expression with syntaxin 1A, it displayed a shift to the plasma membrane, where the two proteins colocalized. These results identified Munc-18-2 as a predominantly epithelial vesicle-transport protein with a polarized distribution and provided novel in vivo evidence for the association of Sec1-related proteins with members of the syntaxin family. 相似文献
55.
This study investigated zoledronate (CGP 42'446), a bisphosphonate, as a potential prophylactic and therapeutic agent against intracortical defects in metaphyseal bone in an experimental model of inflammatory arthritis. Inflammatory arthritis was induced in the right tibiofemoral joint of rabbits by the repeated injection of carrageenan. Three groups of animals were treated with the bisphosphonate daily, beginning at different points after the induction of arthritis. Cross sections of the right distal femoral metaphysis were prepared, and intracortical defects were examined by computerized image analysis. The percentage of total bone area with defects (the ratio of void area to total bone area) was greatly increased in the arthritic group compared with that in the normal group (p < 0.001). In all groups treated with the bisphosphonate, there was a significantly lower percentage of total bone area with defects compared with that in the arthritic group (p < 0.001). Treatment was likewise effective in reducing the zonal (anterior and posterior) predilection for the formation of defects observed in arthritis. Although inflammatory arthritis has a substantial effect in producing intracortical defects in metaphyseal bone, a bisphosphonate, zoledronate, was considerably effective in preventing these changes from occurring. 相似文献
56.
H. K. Charles Jr. K. J. Mach S. J. Lehtonen A. S. Francomacaro J. S. DeBoy R. L. Edwards 《Microelectronics Reliability》2003,43(1):141-153
Higher-frequency ultrasonics have been utilized to improve the bondability of difficult substrates, i.e., substrates that would not bond or that bonded poorly using conventional ultrasonics (nominally at 60 kHz). A systematic study of the influence of higher-frequency ultrasonics on bond strength and the bondability of various substrates is reported. The studies were carried out using two essentially identical thermosonic ball bonding machines, one bonding at nominally 60 kHz and the other at 100 kHz. The only differences between the bonding machines were the ultrasonic generators’ operating frequency and the transducer horns. Key to the study was the ability to make the bonding experiments as controlled, repeatable, and independent of all variables (except frequency) as possible. Control techniques included setting the electronic flame-off to produce consistently sized free-air balls; monitoring the ultrasonic voltage and current waveforms; and picking force, dwell, energy, and substrate heat settings that would allow strong bonds to be formed at both frequencies. Wirebonds (ball bonds) in this study were evaluated primarily by the ball bond shear test. Statistical methods were used to determine whether the differences in the means and variances between comparable samples sets (one bonded at 60 kHz and the other bonded at 100 kHz) were significant. Results of our studies indicate that significant differences exist between bonding at nominally 60 kHz and bonding at 100 kHz. In particular, we describe effects associated with (1) the ball shear strength before and after thermal aging (temperatures up to 200 °C) for both 60- and 100-kHz bonds, (2) the influence of substrate-metallizations combinations on the geometry and strength of the bonds at the different frequencies, and (3) the sensitivity and control of the overall bonding processes. 相似文献
57.
Heine P. Pohjanheimo P. Lehtonen M. Lakervi E. 《Power Systems, IEEE Transactions on》2002,17(2):290-296
The annual number and cost of voltage sags were determined for five Finnish distribution companies. The method of fault positions was applied for the calculation of voltage sag frequency. The economic consequences were assessed by multiplying the sag frequency and cost by the number of customers. The cost of a single sag was taken from a survey that had been carried out in three Nordic countries in the mid 1990s. This paper proposes a method for retrieving sag-related information from statistics originally prepared for other purposes. In addition, this paper provides an estimate of the total annual sag-related cost for each of the companies considered in this study and for each customer category. The total cost per company appeared to be much higher than had generally been assumed 相似文献
58.
Amino acid‐derived betaines dominate as urinary markers for rye bran intake in mice fed high‐fat diet—A nontargeted metabolomics study
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59.
Markku Lehtonen 《Planning Theory & Practice》2019,20(2):203-220
Trust is vital in participatory planning. To explore the complex relationships between participation and various dimensions of trust and mistrust, this article develops a framework of analysis distinguishing between specific and diffuse forms of institutional trust and mistrust, and illustrates its relevance via two case studies of urban and transport planning in Finland and Sweden. We explore the dynamic coexistence of mistrust towards the specific planning organisations in charge of the projects with the strong ‘diffuse’ trust in the generic institutions of representative democracy and Nordic planning. The proposed approach can help harness mistrustful civic vigilance for deliberative purposes. 相似文献
60.