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61.
In hierarchical reliable multicast schemes, the number of repair proxies and their locations influence inter-destination synchronization.
The inter-destination synchronization in multicast environments means the adjustment of the output timing among destinations
over the Internet. Improving the inter-destination synchronization is beneficial to collaborative applications such as multi-conference
system and multi-playing online game. In this paper, we propose a scheme to find the optimal locations of repair proxies that
can improve inter-destination synchronization maximally in heterogeneous network environments. The simulation results show
that if repair proxies are placed by the proposed scheme, delivery delay fairness of inter-destination can be improved by
0.05 maximally. In addition, we perform t-Test on the simulation results in order to verify that our optimal placement improves synchronization. 相似文献
62.
Budiono Doyoung Byun Vu dat Nyugen Jihoon Kim Han Seo Ko 《Journal of Mechanical Science and Technology》2008,22(12):2554-2562
We propose a novel micro/nano-scale nozzle structure, featuring an interfacial line between the hydrophilic and the hydrophobic
surfaces for a jetting system, such as an inkjet head or electrospray devices. This research will investigate the impact of
the interfacial line on flow instability and momentum augmentation as the liquid meniscus moves across the line. The research
methods used in this paper, in respect to micro-and nano-scale channels, are computational fluid dynamics (CFD) and non-equilibrium
molecular dynamics (MD), respectively. With the growing interest in micro/nano electromechanical systems (MEMS/NEMS), many
studies have been conducted to develop an advanced micro/nanofluidic system. However, until now, there have been few in-depth
studies on passive flow control in micro and nano nozzles using the hydrophilic and hydrophobic surface characteristics. In
this research, the sequential arrangement of hydrophilic and hydrophobic surfaces in the nozzle is presented along with an
investigation into how flow instability and momentum augmentation are going to be applied to an efficient micro/nano jetting
system. When a liquid meniscus arrives at the interfacial line between hydrophilic and hydrophobic surfaces, the meniscus
shape changes from concave to convex and the fluid motion near the wall stops until the concave shape is fully converted.
Because the momentum should be conserved, the lost momentum near the wall transfers to the center region, and therefore the
liquid at the center region is accelerated as it crosses the line. If we use this nozzle structure and the augmentation of
the momentum near the center, a tiny droplet can be easily generated.
This paper was recommended for publication in revised form by Associate Editor Haecheon Choi
Doyoung Byun received the B.S., M.S, and Ph.D. degrees in school of mechanical and aerospace engineering from the Korea Advanced Institute
of Science and Technology (KAIST), Taejon, Korea, in 1994, 1996, and 2000, respectively. From 2000 to 2002, he was in the
Korea Institute of Science and Technology Evaluation and Planning as a Senior Researcher. In 2003, he joined the faculty of
the School of Mechanical and Aerospace Engineering, Konkuk University, Seoul, Korea. His current research topics are development
of electrohydrodynamic inkjet head, microfluidic devices, and biomimetic robot systems. His research interests include microfluidics,
MEMS, and biomimetics. 相似文献
63.
Ho-Lim Choi Hee-Jung Byun Won-Gyu Song Jun-Won Son Jong-Tae Lim 《Artificial Life and Robotics》2000,4(4):193-197
We present a method to calssify electromyogram (EMG) signals which are utilized as control signals for a patient-responsive
walker-supported system for paraplegics. Patterns of EMG signals for different walking motions are classified via adequate
filtering, real EMG signal extraction, AR-modeling, and a modified self-organizing feature map (MSOFM). In particular, a data-reducing
extraction algorithm is employed for real EMG signals. Moreover, MSOFM classifies and determines the results automatically
using a fixed map. Finally, the experimental results are presented for validation. 相似文献
64.
Junggeun Jhin Jong Hyeob Baek Dongjin Byun 《Journal of the Society for Information Display》2008,16(4):535-539
Abstract— The structural, electrical, and optical properties of GaN epilayers grown on various ion‐implanted sapphire(0001) substrates by MOCVD were investigated. GaN or AlN buffer layers and pre‐treatment were indispensably introduced before GaN‐epilayer growth. The ion‐implanted substrate's surface had decreased internal free energies during the growth of the ion‐implanted sapphire(0001) substrates. The crystal and optical properties of the GaN epilayers grown in ion‐implanted sapphire(0001) substrates were improved. Also, an excessively roughened and modified surface caused by ions degraded the GaN epilayers. Not only the ionic radius but also the chemical species of implanted sapphire(0001) substrates improved the properties of the GaN epilayers grown by MOCVD. It is obvious that the ion‐implanted pre‐treatment of sapphire(0001) substrates can be an alternative pre‐treatment procedure for GaN deposition and has the potential to improve the properties of the GaN epilayers on sapphire(0001) substrates. 相似文献
65.
In this paper, interface circuits that are suitable for point‐to‐point interconnection with an over 1 Gbps data rate per pin are proposed. To achieve a successful data transfer rate of multi‐gigabits per‐second between two chips with a point‐to‐point interconnection, the input receiver uses an on‐chip parallel terminator of the pass gate style, while the output driver uses the pullup and pulldown transistors of the diode‐connected style. In addition, the novel dynamic voltage level converter (DVLC) has solved such problems as the access time increase and valid data window reduction. These schemes were adopted on a 64 Mb DDR SRAM with a 1.5 Gbps data rate per pin and fabricated using a 0.10 µm dual gate oxide CMOS technology. 相似文献
66.
Seung Wook Yoon Jun Ki Hong Hwa Jung Kim Kwang Yoo Byun 《Electronics Packaging Manufacturing, IEEE Transactions on》2005,28(2):168-175
To evaluate various Pb-free solder systems for leaded package, thin small outline packages (TSOPs) and chip scale packages (CSPs) including leadframe CSP (LFCSP), fine pitch BGA (FBGA), and wafer level CSP (WLCSP) were characterized in terms of board level and mechanical solder joint reliability. For board level solder joint reliability test of TSOPs, daisy chain samples having pure-Sn were prepared and placed on daisy chain printed circuit board (PCB) with Pb-free solder pastes. For CSPs, the same composition of Pb-free solder balls and solder pastes were used for assembly of daisy chain PCB. The samples were subjected to temperature cycle (T/C) tests (-65/spl deg/C/spl sim/150/spl deg/C, -55/spl deg/C/spl sim/125/spl deg/C, 2 cycles/h). Solder joint lifetime was electrically monitored by resistance measurement and the metallurgical characteristics of solder joint were analyzed by microstructural observation on a cross-section sample. In addition, mechanical tests including shock test, variable frequency vibration test, and four point twisting test were carried out with daisy chain packages too. In order to compare the effect of Pb-free solders with those of Sn-Pb solder, Sn-Pb solder balls and solder paste were included. According to this paper, most Pb-free solder systems were compatible with the conventional Sn-Pb solder with respect to board level and mechanical solder joint reliability. For application of Pb-free solder to WLCSP, Cu diffusion barrier layer is required to block the excessive Cu diffusion, which induced Cu trace failure. 相似文献
67.
Hee-Jung Park Jeong-Min Ko Seong-Ho Jang Jae-Hee Hong 《Food science and biotechnology》2017,26(2):427-434
This study compared the perception of and preference for seven bulgogi marinade sauces between Korean and Japanese consumers. Flash profiling (10 panelists each) and consumer test (97 Japanese and 102 Koreans) were conducted. Results showed that both Korean and Japanese panelists perceived the samples similarly but described using different terms. There were significant crosscultural differences in most liking and just-about-right attributes, except texture liking and sweetness. Both consumer panelists preferred sweeter samples, but Japanese consumers rated liking for less sweet samples higher than Korean consumers. Japanese consumers considered strong saltiness, umami, and soy sauce flavor as “just-about-right,” whereas Korean consumers considered the same levels as “much too strong”. Familiarity showed a significantly positive correlation with both Korean and Japanese consumers’ liking, but authenticity was only significantly correlated with Korean consumers’ liking. This indicates that perception of authenticity might not have a strong impact on Japanese consumers’ liking. 相似文献
68.
Kim Da Hyun Kim Jae Hwan Kim Da Hyun Jo Jay-Young Byun Sanguine 《Food science and biotechnology》2022,31(5):527-538
Food Science and Biotechnology - Viruses are known to cause a variety of diseases, ranging from mild respiratory diseases, such as the common cold, to fatal illnesses. Although the development of... 相似文献
69.
Refrigerant R-410a flow distribution is experimentally studied in a test section simulating a minichannel heat exchanger having vertical headers with two pass configuration. Tubes are heated to yield a test section outlet superheat of 5°C with inlet quality of 0.3. Mass flux is varied from 60 kg/m2-s to 70 kg/m2-s. Effects of outlet locations are investigated in a search for an optimum configuration. The effect of varying the number of tubes of each pass is also investigated. Results show that significant liquid flows through bottom channels, and less liquid is supplied to top channels. For the outlet location, a bottom outlet is better than a middle or top outlet. In addition, assigning a lower number of tubes to inlet pass yields better flow distribution. Correlations are developed for the fraction of liquid or gas taken off by the downstream channel as a function of header gas Reynolds number immediately upstream. The correlations may be used to predict the liquid or gas distribution in a parallel-flow heat exchanger havin vertical headers. 相似文献
70.
Ki Yeol Byun Isabelle FerainJohn Hayes Ran Yu Farzan Gity Cindy Colinge 《Microelectronic Engineering》2011,88(4):522-525
In this work, an alternative method for producing the single crystalline Ge-Si Avalanche photodiodes (APD) with low thermal budget was investigated. Structural and electrical investigations show that low temperature Ge to Si wafer bonding can be used to achieve successful APD integration. Based on the surface chemistry of the Ge layer, the buried interfaces were investigated using high resolution transmission electron microscopy as a function of surface activation after low temperature annealing at 200 and 300 °C. The hetero-interface was characterized by measuring forward and reverse currents. 相似文献