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如何利用光周期提高鹿的冬季生长速度
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作者 刘大荣 王树贤 《野生动物》 1995年第2期39-43,共5页
如何利用光周期提高鹿的冬季生长速度(新西兰)吉姆斯·M·萨提等前言温带的鹿类常表现出季节性生长,也就是说活体体重的增长在春夏两季比秋冬季节快。当年的雄性马鹿断奶后在秋季长势很好,日增重为300g,但在冬季从5... 如何利用光周期提高鹿的冬季生长速度(新西兰)吉姆斯·M·萨提等前言温带的鹿类常表现出季节性生长,也就是说活体体重的增长在春夏两季比秋冬季节快。当年的雄性马鹿断奶后在秋季长势很好,日增重为300g,但在冬季从5月到8月①其最大增长速度为150g/d左右... 展开更多
关键词 鹿 光周期 冬季 生大速度 马鹿 圈舍 饲料
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Dynamics of the Currents in the Strait of Khuran in the Persian Gulf 被引量:1
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作者 N.H. Zaker P. Ghaffari +1 位作者 S. Jamshidi M. Nourian 《Journal of Shipping and Ocean Engineering》 2011年第2期109-115,共7页
The Strait of Khuran is among the most important marine habitats in the Persian Gulf. It is the location of the largest Avicennia Marina mangroves along the Persian Gulf shoreline and is a major nursery region for the... The Strait of Khuran is among the most important marine habitats in the Persian Gulf. It is the location of the largest Avicennia Marina mangroves along the Persian Gulf shoreline and is a major nursery region for the fish and to breeding, wintering and migrant water birds. This paper presents dynamics of the currents in the Strait of Khuran using the current data collected by fixed current meters. The analysis of the data showed that the currents in the Strait of Khuran were highly dominated by tidal forcing with mixed semi diurnal behavior. The tidal currents were strong and reached to a maximum velocity of 123 cm/s in the spring tide. Tidal analysis showed that the tidal current constituents (M2, $2, N2, K1, O1) are dominant with M2 component as the major one. The tidal currents occurred basically along the strait. The results show a westward residual flow along the strait with an average of 5.6 cm/s during the study. The direction of the flow indicates that any pollution discharged into the industrial developing eastern part of the strait has the potential to affect the sensitive ecosystem in the western part. 展开更多
关键词 Strait of Khuran marine habitat tidal currents harmonic analysis.
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Optimization of Resource in the Industry of Construction
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作者 Francisco Javier Gutierrez Garcia Pedro Perez Diaz Pedro Sanchez Luis 《Journal of Civil Engineering and Architecture》 2014年第9期1145-1150,共6页
Time and cost are two of the most important factors to consider in each construction project. In order to maximize performance, both the client and the contractor will work to optimize both the duration of the project... Time and cost are two of the most important factors to consider in each construction project. In order to maximize performance, both the client and the contractor will work to optimize both the duration of the project and its cost. We show a model of linear entire mixed programming to solve the considered problem. The aim is to minimize the project total time, by means of the assignment of equipments of work to the different production lines of the activities to realizing. The fundamental beginning is to support the same production (rate of production in meters/day of the activity in view of the equipment of work) for tbe different equipments to achieve the maximum efficiency in each period of time. With the limited availability of resources, the work must be continuous and the period of time between operations and final must be kept. However, this paper also presents the bibliographical study on methodologies of the optimization of construction processes in response to the two objectives: time and cost. This will consider the use of recta-heuristic techniques, such as population based algorithms. 展开更多
关键词 OPTIMIZATION construction process HEURISTICS mathematical programming.
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Technology Use Takes a Boost among University Students
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《Computer Technology and Application》 2012年第4期347-354,共8页
The speed with which the information technology has evolved is unparallel to any other technological evolution man has ever witnessed. From hospitals to classrooms, technology seems to have taken over people's lives.... The speed with which the information technology has evolved is unparallel to any other technological evolution man has ever witnessed. From hospitals to classrooms, technology seems to have taken over people's lives. Where there have been studies to see the impact of technology in varying aspects of life, there seem to be little or no studies on the actual rate of increase in usage of e-technologies among university students and why they have become so popular. This paper uses a survey tool that captures responses from 900 students to study the rate of increase in student use of various e-technologies in and out of classrooms along with some viable reasons why students are acquiring and using such technologies and suggests ways to use this study to better understand student behavior in terms of e-cheating, and how to enhance teaching and learning environments for students. 展开更多
关键词 EDUCATION e-technologies information technology university students boost.
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The diagnostic value of transrectal ultrasonographic features in prostate cancer
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作者 Xiaoli Zou Guang Yang Hui Wang 《The Chinese-German Journal of Clinical Oncology》 CAS 2012年第4期229-232,共4页
Objective:The aim of the study was to detect the valuable ultrasonographic features in diagnosing prostate cancer.Methods:The patients who underwent transrectal ultrasound in the period from May 2005 to October 2009 a... Objective:The aim of the study was to detect the valuable ultrasonographic features in diagnosing prostate cancer.Methods:The patients who underwent transrectal ultrasound in the period from May 2005 to October 2009 at the 1st Affiliated Hospital of Dalian Medical University,China,were included,with needle biopsy diagnosis for patients with the prostate cancer and prostatic hyperplasia.Seventy-four cases of prostate cancer were diagnosed as adenocarcinoma,compared with 51 cases diagnosed as prostatic hyperplasia.Retrospective analysis of patients with transrectal ultrasound were done,comparing the difference between the two groups in the echo level (hypoechogenic),outlines (ill-defined margin),posterior acoustic attenuation,periphery halo,microcalcification incidence,the blood supply level,peak systolic velocity (Vs) and resistance index (RI).Results:The ratios of hypoechogenic lesions in the prostate cancer group and prostatic hyperplasia group were 56.76% and 35.90%,respectively (P<0.05),the ratios of irregular outlines were 85.14% and 15.38% respectively (P<0.05),the ratios of microcalcification were 39.19% and 10.26%,respectively (P < 0.05),the ratios of posterior acoustic attenuation were 41.89% and 12.82%,respectively (P<0.05),and the ratios of periphery halo were 35.14% and 38.46% respectively (P>0.05).Vs of the two groups were (44.00 ± 15.30) cm/s and (17.32 ± 4.65) cm/s,respectively (P<0.05).RI of the two groups were 0.76 ± 0.10,and 0.51 ± 0.03 respectively (P<0.05).The significant correlation was designated in the blood supply level between the prostate cancer group and prostatic hyperplasia group (r=-0.388,P<0.01).Higher revascularization grade was seen in the prostate cancer group compared to benign prostatic hyperplasia group.Conclusion:(1) The significant roles for diagnosing prostate cancer are hypoechogenic,irregular outlines,spiculation,microcalcification,high revascularization grade,posterior acoustic attenuation,high Vs and high RI.(2) It could not help in diagnosing prostate cancer with ultrasonographic periphery halo or not. 展开更多
关键词 transrectal ultrasound prostate cancer DIAGNOSIS
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