Wyniki wyszukiwania - Biblioteka Nauki

1

Ecological stoichiometric characteristics of soil at different depths in a karst plateau mountain area of China

100%

Yu Y. , Chi Y.

Polish Journal of Environmental Studies

|

2020

|

tom 29

|

nr 1

2

Distribution characteristics of selenium nutrition on the natural habitat of Przewalski’s gazelle

80%

Chi Y. , Huo B. , Shen X.

Polish Journal of Environmental Studies

|

2020

|

tom 29

|

nr 1

3

Research on photosynthetic leguminous forage in the karst rocky desertification regions of southwestern China

80%

Xiong K. , Chi Y. , Shen X.

Polish Journal of Environmental Studies

|

2017

|

tom 26

|

nr 5

EN

The photosynthetic characteristics of three kinds of leguminous forages were studied in a karst rocky desertification area of Guizhou using the photosynthetic apparatus on sunny days. The results showed that the curves of annual diurnal variation of the net photosynthetic rate and transpiration rate on three kinds of experiment forges showed different variation trends that were mainly related to the experimental materials. They showed that there were significant differences in the net photosynthetic and transpiration rates of different grasses, and also in photosynthetic physiology changes of different seasons. Through the annual photosynthetic physiological studies among Trifolium repens, Trifolium pretense, Medicago sativa, and other forage legumes can be concluded that the highest annual average net photosynthetic rate of leguminous forage was Medicago sativa followed by Trifolium repens, and Trifolium pretense was the lowest; the highest transpiration rate was Trifolium pretense followed by Trifolium repens, and the lowest was Medicago sativa, with little differences of this three leguminous forage. The highest photosynthetic efficiency and the lowest transpiration rate make the water use efficiency of Medicago sativa the highest, followed by Trifolium repens, and the lowest was Trifolium pretense. In most months, Trifolium repens, Trifolium pretense, and Medicago sativa were sensitive to high photosynthetic active radiation and high temperature, so taking a dormant form with closing their pores to reduce its water loss and material consumption. The primary productivity of grassland depends largely on water use efficiency. When establishing artificial grassland in the karst rocky desertification area we need to consider the net photosynthetic rate, transpiration rate, and water use efficiency, and take measures to use different kinds of forage, which not only reduce water loss but also improve water use efficiency and ease drought and water shortage in rocky desertification areas. From considering the overall perspective of annual photosynthetic physiological characteristics, Medicago sativa is more suitable than Trifolium repens and Trifolium pretense for the habitat conditions in light-moderate karst rocky desertification areas.

4

Frequent Subtree Mining : An Overview

80%

Chi Y. , Muntz R. R. , Nijssen S. , Kok J. N.

Fundamenta Informaticae

|

2005

|

tom Vol. 66, nr 1,2

161--198

EN

Mining frequent subtrees from databases of labeled trees is a new research field that has many practical applications in areas such as computer networks, Web mining, bioinformatics, XML document mining, etc. These applications share a requirement for the more expressive power of labeled trees to capture the complex relations among data entities. Although frequent subtree mining is a more difficult task than frequent itemset mining, most existing frequent subtree mining algorithms borrow techniques from the relatively mature association rule mining area. This paper provides an overview of a broad range of tree mining algorithms. We focus on the common theoretical foundations of the current frequent subtree mining algorithms and their relationship with their counterparts in frequent itemset mining. When comparing the algorithms, we categorize them according to their problem definitions and the techniques employed for solving various subtasks of the subtree mining problem. In addition, we also present a thorough performance study for a representative family of algorithms.

5

Effects of fertilization on physiological and biochemical parameters of Wumeng sheep in China’s Wumeng Prairie

70%

Chi Y. , Zhang Z. , Song C. , Xiong K. , Shen X.

Polish Journal of Environmental Studies

|

2020

|

tom 29

|

nr 1

6

Effect of grazing to copper pollution meadow on copper metabolism in Wumeng semi-fine wool sheep

61%

Chi Y. , Xiong K. , Chen H. , Min X. , Xiao H. , Liao J. , Shen X.

Polish Journal of Environmental Studies

|

2019

|

tom 28

|

nr 3

EN

To assess the effect of copper pollution meadow on grazing Wumeng semi-fine wool sheep and find an action plan to solve copper pollution, two experiments (grazing and sulfur supplementation) were conducted on copper pollution meadow at Wumeng mountainous area in Weining County of Guizhou Province. The contents of heavy metal elements were analyzed by inductively coupled plasma atomic emission spectroscopy (ICP-AES) in soil, pasture, and animal tissues, and the blood parameter was determined by automatic blood cell analyzer. The results of grazing experiments showed that the content of copper and zinc in animal tissues when Wumeng semi-fine wool sheep grazed in the copper-polluted meadow were significantly increased (P<0.01), but the molybdenum content in animal tissues significantly decreased (P<0.01). At the end of experiment, the Hb, PCV, and RBC of the experimental Wumeng semi-fine wool sheep were significantly lower than control group (P<0.01), and mean corpuscular volume (MCV) was significantly lower than the control group (P<0.05), and the wool yield and length were significantly lower than not the control group (P<0.01). The results of the sulfur supplementation experiment showed that the supplementation of sodium sulfate significantly reduced the copper element content in blood and liver of Wumeng semi-fine wool sheep, the hemoglobin (Hb), packed cell volume (PCV), and red blood cell count (RBC) in blood of the experimental Wumeng semi-fine wool sheep were significantly higher than the control group (P<0.01), and the blood parameter reached the normal range at the end of the experiment. The content of copper element in blood and liver of the control group continued to increase, and the content of molybdenum in the animal tissues continued to decrease (P<0.01). The Hb, PCV, RBC, and MCV of the experimental Wumeng semi-fine wool sheep continued to decline, and hemolytic anemia was seen in Wumeng semi-fine wool sheep from control group at the end of experiment. However, sulfur supplementation had no significant effect on the relevant indicators of wool quality. Conclusion: copper pollution meadow seriously affect the mineral metabolism of Wumeng semi-fine wool sheep, and we can utilize the antagonism of sulfur and copper in the food chain to achieve the goal of harmless utilization of copper pollution meadow.

7

Research on the statistical characteristics of crosstalk in naval ships wiring harness based on Polynomial Chaos Expansion method

61%

Chi Y. , Li B. , Yang X. , Wang T. , Yang K. , Gao Y.

Polish Maritime Research

|

2017

|

tom S 2

205--214

EN

Crosstalk in wiring harness has been studied extensively for its importance in the naval ships electromagnetic compatibility field. An effective and high-efficiency method is proposed in this paper for analyzing Statistical Characteristics of crosstalk in wiring harness with random variation of position based on Polynomial Chaos Expansion (PCE). A typical 14-cable wiring harness was simulated as the object of research. Distance among interfering cable, affected cable and GND is synthesized and analyzed in both frequency domain and time domain. The model of naval ships wiring harness distribution parameter was established by utilizing Legendre orthogonal polynomials as basis functions along with prediction model of statistical characters. Detailed mean value, mean square error, probability density function and reasonable varying range of crosstalk in naval ships wiring harness are described in both time domain and frequency domain. Numerical experiment proves that the method proposed in this paper, not only has good consistency with the MC method can be applied in the naval ships EMC research field to provide theoretical support for guaranteeing safety, but also has better time-efficiency than the MC method. Therefore, the Polynomial Chaos Expansion method.

8

Research on the statistical characteristics of crosstalk in naval ships wiring harness based on Polynomial Chaos Expansion method

61%

Chi Y. , Li B. , Yang X. , Wang T. , Yang K. , Gao Y.

Polish Maritime Research

|

2017

|

tom 24

|

nr Special Issue S2

EN

Crosstalk in wiring harness has been studied extensively for its importance in the naval ships electromagnetic compatibility field. An effective and high-efficiency method is proposed in this paper for analyzing Statistical Characteristics of crosstalk in wiring harness with random variation of position based on Polynomial Chaos Expansion (PCE). A typical 14-cable wiring harness was simulated as the object of research. Distance among interfering cable, affected cable and GND is synthesized and analyzed in both frequency domain and time domain. The model of naval ships wiring harness distribution parameter was established by utilizing Legendre orthogonal polynomials as basis functions along with prediction model of statistical characters. Detailed mean value, mean square error, probability density function and reasonable varying range of crosstalk in naval ships wiring harness are described in both time domain and frequency domain. Numerical experiment proves that the method proposed in this paper, not only has good consistency with the MC method can be applied in the naval ships EMC research field to provide theoretical support for guaranteeing safety, but also has better time-efficiency than the MC method. Therefore, the Polynomial Chaos Expansion method