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51.
In this paper, a mass spring system is developed to simulate the draping behavior of knitted fabric. A new type of mesh based on loop structure, which is called Loop mesh, is introduced. The effective properties on fabric drape are measured using the Fast system, and the experimental data are incorporated into the mass spring model to simulate the draping behavior of knitted fabrics. 3D shape of real drape behavior of fabric samples is achieved using depth camera. Then in order to reduce error value between simulated and real results, distances between mass points in the Loop mesh are optimized using the Imperialistic Competitive Algorithm (ICA). In order to investigate validity and accuracy of the Loop mesh, drape behavior of knitted fabrics falling over a square table are also simulated using common meshes. It can be found that the Loop mesh produced a closest drape shape to the real fabric drape than other mesh models. Finally, fabrics drape is simulated in other situations and compared with its real result to validate the proposed model. Results show that the optimized model is able to simulate the drape behavior of knitted fabric with error value of 4.29 percent.  相似文献   
52.
Aerobic granules to treat wastewater containing o-nitrophenol were successfully developed in a sequencing batch reactor (SBR) using activated sludge as inoculum. Stable aerobic granules were obtained with a clearly defined shape and diameters ranging from 2 to 6 mm after 122 days of operation. The integrity coefficient (IC) and granules density was found to be 98% and 1,054 kg m(-3) respectively. After development of aerobic granules, o-nitrophenols were successfully degraded to an efficiency of 78% at a concentration of 70 mg L(-1). GC-MS study revealed that the biodegradation of o-nitrophenol occurred via catechol via nitrobenzene pathway. Specific o-nitrophenol biodegradation rates followed the Haldane model and the associated kinetic parameters were found as follows: V(max) = 3.96 g o-nitrophenol g(-1)VSS(-1)d(-1), K(s) = 198.12 mg L(-1), and K(i) = 31.16 mg L(-1). The aerobic granules proved to be a feasible and effective way to degrade o-nitrophenol containing wastewater.  相似文献   
53.
Epilepsy is a type of brain disorder that causes recurrent seizures. It is the second most common neurological disease after Alzheimer’s. The effects of epilepsy in children are serious, since it causes a slower growth rate and a failure to develop certain skills. In the medical field, specialists record brain activity using an Electroencephalogram (EEG) to observe the epileptic seizures. The detection of these seizures is performed by specialists, but the results might not be accurate due to human errors; therefore, automated detection of epileptic pediatric seizures might be the optimal solution. This paper investigates the detection of epileptic seizures by applying supervised machine learning techniques. The techniques applied on the data of patients with ages seven years and below from children’s hospital boston massachusetts institute of technology (CHB-MIT) scalp EEG database of epileptic pediatric signals. A group of Naïve Bayes (NB), Support vector machine (SVM), Logistic regression (LR), k-nearest neighbor (KNN), Linear discernment (LD), Decision tree (DT), and ensemble learning methods were applied to the classification process. The results demonstrated the outperformance of the present study by achieving 100% for all parameters using the Ensemble learning model in contrast to state-of-the-art studies in the literature. Similarly, the SVM model achieved performance with 98.3% for sensitivity, 97.7% for specificity, and 98% for accuracy. The results of the LD and LR models reveal the lower performance i.e., the sensitivity at 66.9%–68.9%, specificity at 73.5%–77.1%, and accuracy at 70.2%–73%.  相似文献   
54.
Micromorphology of 15 grass caryopsis was investigated through scanning electron microscopy for its implications in the identification of grasses. Both macro and micromorphological characters especially caryopsis shape and surface morphology were found significant in the taxonomic diagnosis. Shape morphology of caryopsis varied among the species and lanceolate, fusiform, narrow ellipsoidal, ovate, elliptical, plano-convex, fusiform, linear ovate, broadly elliptical, broadly pllipsoidal, plano-convex, oblique ovate, and subglobose shapes were recorded. Digitaria nodosa (3.31 × 0.7 mm) and Echinochloa crus-galli (3.26 × 1.44 mm) had the largest caryopsis size, while Acrachne racemosa (0.76 × 0.54 mm) and Eragrostis minor (0.62 × 0.38 mm) had the smallest caryopsis size. Macro and micromorphological characters were useful for the diagnosis of genus and species. Utilizing both qualitative and quantitative character taxonomic key at generic and species level were made.  相似文献   
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56.
Chitosan (CS) is a promising candidate for green anticorrosive coating owing to its film forming nature, complexation with metals, biocompatibility, and varied surface functionalization. This paper illustrates the surface properties of chitosan film which is modified by grafting with stearic acid via a water-soluble coupling agent, 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC). The interaction between chitosan and stearic acid were investigated theoretically by Gaussian 09 package. The purified co polymeric films so formed were characterized by FTIR-ATR, NMR, XRD, TGA, CHNSO, SEM, AFM and EDX techniques. Stearic acid grafted CS film was developed on mild steel surface via dip coating technique and investigated for its corrosion resistance in 3.5% NaCl via electrochemical techniques. EIS measurements and potentiodynamic polarization studies have proven that the grafted CS when blended with epoxy resin offers better corrosion protection to mild steel in saline environment. The coating offers prolonged protection for the metal surface with enhanced barrier properties and hydrophobic nature.  相似文献   
57.
ZnTe films were deposited on glass substrates at different substrate temperatures in the range 30–300 °C. The thickness of the films was about 200 nm. The films exhibited cubic structure with preferential orientation in the (111) direction. Band gap values in the range 2.34–2.26 eV are observed with increase of the substrate temperature. The refractive index values are in the range of 2.55–2.92 for the films deposited at different substrate temperatures. It is observed that the conductivity increases continuously with temperature. Laser Raman studies indicated the presence of peaks at 206.9 and 412.2 cm−1corresponding to the first order and second order LO phonon.  相似文献   
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59.
Edge curling is a unique property of knitted fabrics which affects on fashion such as using upper and side curling in cloth design. The purpose of this research is to present a new method to simulate drape behavior of knitted fabric considering difference between single and double jersey knitted fabrics. To this point, at first the bending and torsion moments that applied on the fabric edges and caused curling in single knitted fabric are determined. Also it demonstrated that these moments will be neutralized in double knitted and as the results, leads to a non-curling structure. Then, using the mass spring model, curling shape in fabric wale and course directions are simulated. To show efficiency of the proposed model, real 3D shape of single knitted fabric is compared with experimental results. Also, using the proposed model, the drape behaviors of single and double jersey knitted fabrics hanging from two fixed corners with different properties are simulated and then extend to simulation of skirt. Results of simulation are compared with 3D shapes of actual drape behavior in fabric samples which are achieved by depth camera. The simulated results show good agreement with 3D shapes of actual fabrics.  相似文献   
60.
在钢筋混凝土结构服役寿命中,混凝土强度是联系结构安全性的重要指标。较为准确地检测混凝土质量,对于结构物而言是十分重要的。进行了英国女王大学研发的LIMPET混凝土强度监测设备对于中国混凝土的适用性验证。采用LIMPET拔出试验仪和液压式万能试验机对几种国内常用混凝土强度的试件进行测试,对数据进行统计分析之后,总结出国内常用混凝土的LIMPET拔出强度与轴心抗压强度之间的相关关系曲线,对现场评估结构物中混凝土强度提供相关依据,也为LIMPET仪器在中国的标准化提供试验支持。  相似文献   
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