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21.
We report a case of primary choriocarcinoma of the cervix in which the patient died 9 months later. The treatment consisted to administer 5 cycles of chemotherapy pre-operatively and a colpohysterectomy. The pathogeny is a cervical migration of trophoblastics cells after a normal or molar pregnancy which degenerate to choriocarcinoma.  相似文献   
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An authentication watermark is a hidden data inserted into an image that can be used to detect any accidental or malicious alteration in the image. Many authentication‐watermarking techniques for continuous‐tone images are described in the literature, but only a quite small number of secure authentication watermarking techniques are available for binary/halftone images. This article proposes a simple solution for inserting a secure authentication watermark in binary/halftone images. It consists of choosing a set of pseudo‐random pixels in the image, clearing them, computing the message authentication code (or the digital signature) of the now‐cleared image, and inserting the resulting code into the selected random pixels. Dispersed‐dot halftone images watermarked by the proposed technique present better visual quality than do watermarked generic binary images. However, in practice, the visual degradation is hardly noticeable in either case. The proposed technique seems to be the only binary/halftone watermarking scheme that can detect even a single pixel alteration in the host image. It can be used with secret‐key or public‐key ciphers. © 2004 Wiley Periodicals, Inc. Int J Imaging Syst Technol 14, 147–152, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ima.20018  相似文献   
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“Rambak” crackers are one of the traditional foods consumed among Indonesian people made from various kinds of animal skin. The present study highlights the analysis of lard obtained from extraction of “rambak” crackers using Fourier transform infrared (FTIR) spectroscopy in combination with chemometrics of partial least square and principle component analysis. FTIR spectroscopy at wavenumber regions of 1200–1000 cm–1 was successfully used for quantification and classification of lard in “rambak” crackers. The relationship between actual value of lard and Fourier transform infrared predicted value has R2 value of 0.946 with low errors in calibration and validation models. Furthermore, the chemometrics principle component analysis can be successfully used for determination of pig skin through analysis of lard in commercial “rambak” crackers. The developed method (FTIR spectroscopy coupled with chemometrics) is rapid and reliable for quantification and classification of lard in “rambak” crackers.  相似文献   
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Garments made from cotton fabrics can readily absorb perspiration during strenuous activities but give poor performance in terms of wicking and evaporation of the perspiration, resulting in wet sticky feeling to the wearer. The aim of this study was to investigate the effect of design and method of creating wicking channels on the moisture management and air permeability of cotton fabrics. The fabric specimens were printed with hydrophobic fluorocarbon finish using four different print designs, each with two different types of printing squeegees. It was found that both the type of print design and squeegee type significantly affect most of the moisture management properties of the fabric. The study concluded that by selecting a suitable print design and squeegee type, moisture management capability of cotton fabrics can be significantly improved without sacrificing the fabric air permeability.  相似文献   
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Data are presented from an investigation of the use of monophasic contraceptive pills chosen by different age groups. Analyses are made of the data obtained from the Bulgarian Association for Family Planning (BAFP) card index for the last two years. Information is given on the number of observed cycles, type of applied contraceptive pill, aims of their application (contraception, treatment of acne, menstrual disturbances etc.), age of patients, as well as any possible adverse effects--change in blood pressure, bodyweight changes, intermenstrual bleeding, hairiness, breast problems, paraclinical changes, etc. The observed cycles show a very small percentage of adverse effects with hormonal contraception, mainly during the first 2 or 3 cycles, with predominance of intermenstrual bleeding. No bodyweight changes or increased hairiness were observed.  相似文献   
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Afif  Mériem  Ben Hassen  Wafa  Tabbane  Sami 《Wireless Networks》2019,25(3):1083-1097

This paper deals with a new resource allocation algorithm in downlink MIMO-OFDMA systems. The objective is to maximize the system throughput with respect to fairness criteria since some users may experience bad channel conditions for a long time. Known to be NP-hard, the original optimization problem is divided into two sub-problems where radio resource allocation and power allocation are performed separately. Firstly, a recursive PRB allocation algorithm is performed aiming at maximizing the system throughput. In LTE systems, 41% of sub-carriers are considered unused which introduces spectral efficiency loss. As solution, the eNodeB aggregates the unused sub-carriers by each user to construct a “virtual” PRB to be allocated to seldom served user for fairness and throughput increase. Secondly, power allocation is performed to select a more appropriate MCS.

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Downlink transmit diversity modes for WCDMA together with a two fixed-beam antenna array system are compared relative to the single antenna sectorized system in a radio network simulator. The transmit diversity methods investigated are: space-time transmit diversity and closed-loop mode I transmit diversity. Frequency selective (COST 259) and flat fading channels are considered and their impact to speech-only and data-only services is evaluated. A third service, which highlights the system performance of the various advanced antennas, is also investigated.The results in this investigation point out that the diversity gain in flat fading channels is substantial. In frequency-selective fading, the benefits of fixed beam systems is encouraging, whereas transmit diversity methods (especially Space-Time Transmit Diversity) is unsatisfactory.  相似文献   
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In Haiti, nutrient deficiencies and stunting are major public health concerns. These health problems are caused by poor access and consumption of nutrient-rich foods, among other factors. The aim of this study was to assess the diet quality of rural Haitian households and identify its socioeconomic determinants. In August–September 2012, female caregivers from 529 rural households from the Department of Grande Anse participated in a cross-sectional survey. Collected data included household food production activities and socioeconomic characteristics. Diet quality was assessed using the Household Dietary Diversity Score. Its determinants were identified using multiple linear regression analyses. Results revealed that many households consumed oil/fats, condiments/beverages/spices, roots/tubers, and cereals, whereas few households consumed animal-based foods such as meats/organs, dairy products and eggs. Among household-level determinants, the number of adults per household, land ownership, practice of livestock rearing, number of meals consumed by children, use of latrines and accessibility of the dwelling location perceived as difficult were all associated with higher household dietary diversity. Among individual-level variables, respondent participation in petty commerce and practice of agriculture as main occupation, in addition to increased level of education were positively associated with household dietary diversity. In sum, determinants of diet quality were multidimensional and were associated with various factors including socio-economic status, household demographics, and physical environment. Moreover, diet quality is concurrently linked with household- and individual-level determinants. This highlights the need for multisectoral and multilevel interventions to improve household diet quality in Haiti.  相似文献   
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