全文获取类型
收费全文 | 325篇 |
免费 | 18篇 |
专业分类
林业 | 42篇 |
农学 | 10篇 |
基础科学 | 1篇 |
54篇 | |
综合类 | 19篇 |
农作物 | 8篇 |
水产渔业 | 25篇 |
畜牧兽医 | 167篇 |
园艺 | 5篇 |
植物保护 | 12篇 |
出版年
2023年 | 1篇 |
2022年 | 2篇 |
2021年 | 8篇 |
2020年 | 3篇 |
2019年 | 5篇 |
2018年 | 3篇 |
2017年 | 8篇 |
2016年 | 7篇 |
2015年 | 10篇 |
2014年 | 8篇 |
2013年 | 23篇 |
2012年 | 20篇 |
2011年 | 21篇 |
2010年 | 6篇 |
2009年 | 16篇 |
2008年 | 22篇 |
2007年 | 23篇 |
2006年 | 26篇 |
2005年 | 16篇 |
2004年 | 20篇 |
2003年 | 14篇 |
2002年 | 5篇 |
2001年 | 16篇 |
2000年 | 6篇 |
1999年 | 7篇 |
1998年 | 4篇 |
1997年 | 1篇 |
1996年 | 5篇 |
1995年 | 3篇 |
1993年 | 1篇 |
1992年 | 6篇 |
1991年 | 6篇 |
1990年 | 1篇 |
1989年 | 4篇 |
1988年 | 4篇 |
1987年 | 2篇 |
1984年 | 1篇 |
1982年 | 1篇 |
1979年 | 1篇 |
1971年 | 1篇 |
1970年 | 3篇 |
1969年 | 1篇 |
1968年 | 1篇 |
1967年 | 1篇 |
排序方式: 共有343条查询结果,搜索用时 0 毫秒
341.
Automated acoustic method for counting and sizing farmed fish during transfer using DIDSON 总被引:1,自引:0,他引:1
Counting and sizing large farmed fish such as tuna is often performed during their transfer from one net cage to another.
Dual-frequency identification sonar (DIDSON) provides an automated fish counting and sizing tool. However, its counter and
sizer are not suitable for measuring farmed fish because of net movements due to currents and subsequent frequent image breakups.
This paper presents a fully automated acoustic method to count and size farmed fish during fish transfer by using DIDSON imaging.
The background is subtracted from the image after being stabilized by an image phase-only correlation method. The segmentation
of the fish is obtained by tracing the edges with a contour tracing method. To prevent recounting the same fish, a Kalman
filter algorithm was designed and adapted to predict fish movements. Automated counting was performed by analyzing the spatiotemporal
trajectory of the track. The separated fish images were searched for and body length was obtained by summing down the centerline
segments from the head to the tail of the fish. The proposed system was verified using farmed yellowtail, Seriola quinqueradiata (mean total length 83.1 cm) to obtain a sizing error of mean total length within 2.4 cm. 相似文献
342.
Ono M Okuda Y Yazawa S Shibata I Tanimura N Kimura K Haritani M Mase M Sato S 《Avian diseases》2001,45(1):268-275
Two outbreaks of gizzard erosion in slaughtered broiler chickens in Japan were examined pathologically and microbiologically. The prevalences of such lesions were 9%-11% and 4%-50% in the affected flocks. Affected chickens had no clinical signs. Group I fowl adenovirus (FAV) serotype 1 was isolated from gizzard lesions. Histologically, gizzard mucosa were necrotic. Intranuclear inclusion bodies were seen in the enlarged nuclei of degenerating epithelial cells of the gizzard. The keratinoid layer in the erosion was edematous and desquamated and contained degenerative cells. Moderate to marked inflammatory cell infiltration was observed in the lamina propria and perivascular connective tissue in the submucosa and muscle layer. Immunohistochemical staining showed evidence of FAV antigens in the intranuclear inclusion bodies within degenerating epithelial cells. Ultrastructurally, numerous viral particles were demonstrated in the inclusions. 相似文献
343.
This study describes the effect of starch properties of Japanese wheat flours on the quality of white salted noodles (WSN). Starch was isolated from 24 flours of 17 Japanese cultivars and amylose content was determined along with pasting properties by Rapid Visco Analyser (RVA), thermal properties by differential scanning calorimetry (DSC), and the distribution of amylopectin chain length by high‐performance anion exchange chromatography (HPAEC). Twenty flours were used to prepare WSN. As expected, 5–6% lower amylose content was associated with good WSN quality (higher scores in softness, elasticity, and smoothness). RVA analysis indicated that the pasting temperature had the greatest influence on WSN quality, while breakdown and setback showed slight effects on WSN quality. DSC results showed that lower endothermal enthalpy (ΔH) in the amylose‐lipid complex was associated with good WSN quality. Chainlength distribution of amylopectin by HPAEC was not an important factor in relation to WSN quality. 相似文献