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Evolution Characteristics of a Local Strong Hailstorm in Shandong Peninsula

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meteorological and Environmental Research 2019年第6期10卷 9-15页

作者： Zhang Can Mei Chanjuan Xu Ke weihai meteorological Bureau Weihai 264200China meteorological station of Air Force Weifang 261500China

On May 28,2018,a strong hailstorm accompanying gale(with speed of 17 m/s)and hail(with the maximum diameter of 42 mm)occurred in Yantai in Shandong *** on the conventional weather observation,Doppler weather radar,and automatic weather station data,the evolution characteristics of the strong hailstorm in Shandong Peninsula were *** results show that this multi-cell strong storm occurred under the background of high-altitude cold *** strong cold advection at the middle and high altitudes and the weak warm advection at the low altitude formed a strong unstable stratification,and also led to cooling at the middle altitudes at the same *** height of 0 and-20℃dropped significantly,which provided better environmental conditions for the growth of hail in the *** lower temperature 0℃also ensured less melting of hail during falling,and the middle dry layer was conducive to the formation of thunderstorm *** vertical wind shear above medium intensity was the development and maintenance mechanism of thunderstorm cells gradually evolving into a strong *** the analysis of radar echo characteristics,it is found that it was a strong hailstorm weather process caused by the linear multi-cell *** thunderstorm cells that could produce large hail occurred and developed,and the whole process lasted for 2 h under the triggering of the convergence line formed by the interaction of the sea breeze front and ground cold *** had obvious characteristics of hail such as three-body scattering spikes,side-lobe echoes,high-hanging strong echoes,as well as the characteristics of thunderstorm gale such as arcuate echoes,middle-level radial convergence,and back side *** storm development process was accompanied by backward propagation,but the long axis of the line storm was basically perpendicular to the movement direction of the storm,so there was no short-term heavy *** stratification instability conditions,water va

关键词： Hail Three-body scattering spike Bow echo Evolution characteristics Shandong Peninsula

Analysis on Extreme Temperature Indexes in Rongcheng station from 1981 to 2010

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meteorological and Environmental Research 2015年第5期6卷 5-8页

作者： Chen Xiaojing Sun qianqian Teng Zhishan Rongcheng meteorological Administration weihai meteorological Administration

A Based on daily maximum and minimum temperature from Rongcheng station during 1981 -2010, the changing trends of extreme temperature indexes were analyzed. The results show that for the relative indexes, number of warm days （nights） in Rongcheng station showed an increasing trend, while the number of cold days （nights） showed a decreasing trend from 1981 to 2010, but the decreasing trend of number of cold days was small. For the extreme indexes, the extreme maximum temperature, the maximum of extreme minimum temperature and extreme mini- mum temperature increased, while the minimum of extreme maximum temperature decreased from 1981 to 2010. For the absolute indexes, the numbers of frozen days and frost days reduced, and frozen days were less than frost days for all year.

关键词： Rongcheng Extreme temperature indexes Climate change China

Research on virtual node placement optimization strategy of cloud platform for information acquisition

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High Technology Letters 2018年第3期24卷 279-286页

作者：帅愉燕 Wei Gaofeng Zhang Zhaoxin Zhang Lizhe School of Computer Science and Technology Harbin Institute of Technology Rongcheng Relay station Weihai Radio and Television Station Information Security Evaluation Center of Civil Aviation Civil Aviation University of China

A virtual node placement strategy based on service-aware is proposed for an information acquisition platform. The performance preferences and types of services in the information acquisition platform are analyzed as well as a comparison of the running time of services both in virtual node centralized and decentralized placing. All physical hosts are divided into different sub-clusters by using the analytic hierarchy process( AHP),in order to fit service of different performance preferences. In the sub-cluster,both load balance and quality of service are taken into account. Comparing with the heuristic algorithm,the experiment results show that the proposed placement strategy is running for a shorter time. And comparing with the virtual node placement strategy provided by OpenStack,the experiment results show that the proposed placement strategy can improve the execution speed of service in the information acquisition platform,and also can balance the load which improves resources utilization.

关键词： virtual node placement service-aware performance preference analytic hierarchy process (AHP) load balance

Changing Characteristics of Urban Heat Island Effect in weihai City

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meteorological and Environmental Research 2023年第6期14卷 8-15页

作者： Di WANG Qianqian SUN Wenpeng XIN Key Laboratory for meteorological Disaster Prevention and Mitigation of Shandong Jinan 25000China weihai meteorological Bureau Weihai 264200China

Based on the local climate zoning theory and the observation data of hourly temperature of 22 automatic weather stations from 2012 to 2021, K-means clustering algorithm was used to analyze the daily, monthly, seasonal, annual and spatial variation characteristics of urban heat island effect in weihai City in the past 10 years. The results showed that in recent 10 years, the average urban heat island intensity was 1.24 ℃, showing a gradual weakening trend of -0.169 3 ℃/10 a;the summer average heat island intensity was 0.86 ℃, showing a gradual weakening trend of -0.047 5 ℃/10 a. The heat island intensity had obvious diurnal variation characteristics, that is, "it was weak in the day and strong at night". In terms of seasonal variation, heat island effect was the weakest in summer, stronger in spring and autumn, and the strongest in winter. The diurnal, seasonal and annual changes of heat island intensity showed a reverse trend to those of temperature. The high-value area of urban heat island was highly consistent with human residential activity areas and industrial and commercial intensive areas, and the extension trend of heat island intensity was the same as the direction of urban development and construction. The "cold island phenomenon" in some offshore areas was related to the geographical location, terrain and the southeast monsoon trend in summer. The adverse effects of urban heat island effect can be reduced by optimizing the types and distribution of vegetation communities, rationally planning and constructing urban water body, promoting green building materials and adjusting shape design, etc.

关键词： Urban heat island effect Local climate zoning K-means clustering algorithm Automatic weather station

Residual strength model for composite laminates

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Journal of Harbin Institute of Technology(New Series) 2010年第3期17卷 424-426页

作者：边文凤郭景哲杜善义 Postdoctoral Flow station of Materials Science and Engineering Harbin Institute of Technology School of Civil Engineering Harbin Institute of Technology at Weihai

To research the approach of predicting composites fatigue life,the cumulative fatigue damage of fiber-reinforced plastic laminates(FRP) was investigated,and based on the complex exponential function,the residual strength model was obtained. This model can accurately describe the propagation of cumulative fatigue damage of FRP in three stages,especially in the initial stage and the ceasing stage. Applying this model in the experiment with two loading cycles,it can be found that the prediction result has good coincidence with experimental data. So a reliable residual strength model can be provided for studying the cumulative fatigue damage of FRP.

关键词： composite material residual strength fatigue life cumulative damage

Genome Editing in the Olive Flounder(Paralichthys olivaceus)Using CRISPR/Cas9 and a Simple Microinjection System

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Journal of Ocean University of China 2021年第6期20卷 1528-1536页

作者： TAN Xungang WANG Ling WU Zhihao JIAO Shuang WANG Lijuan ZOU Yuxia JIANG Jingteng YOU Feng CAS and Shandong Province Key Laboratory of Experimental Marine Biology Center for Ocean Mega-ScienceInstitute of OceanologyChinese Academy of SciencesQingdao 266071China Laboratory for Marine Biology and Biotechnology Qingdao National Laboratory for Marine Science and TechnologyQingdao 266071China University of Chinese Academy of Sciences Beijing 100049China weihai Fishery Technology Promotion station Weihai 264200China Shenghang Aquatic Science and Technology Co. Ltd.Weihai 264200China

The whole-genome sequence of the olive flounder(Paralichthys olivaceus)provides a basis for gene functional analyses,which is important for the aquaculture *** gene function will help us to select better economic traits such as fast growth and better culture conditions,which further will increase the aquaculture *** knockout is an important reverse genetics approach for in vivo studies of gene *** this study,the CRISPR/Cas9 genome editing method with a microinjection system using a simple braked needle was employed in olive *** injection in embryos,green fluorescent protein expression was detected in 40%of *** proportion of normal-hatched larvae was approximately 50%.Different mutations,including short indels and fragment deletions,were found in our test genes gsdf and ***,we detected more than one mutation in a single *** summary,our microinjection technique and CRISPR/Cas9 can be applied to study gene functions in olive flounder.

关键词： CRISPR/Cas9 gsdf microinjection myomaker needle with brake olive flounder

Effects of different levels of sweet potato in feeds on body composition and digestive enzymes activities of A postichopus japonicas Selenka

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Journal of Oceanology and Limnology 2018年第5期36卷 1835-1842页

作者： ZHAO Bin HU Wei LI Chenglin HAN Sha XU Tao Marine Biology Institute of Shandong Province Qingdao 266104China Shandong Province Fisheries Technology Extension station Jinan 250013China Homey Foods Co.Ltd. Weihai 264305China

The aim of this study was to test the ef fects of including sweet potato tuber and stem powder in feed on the body composition and digestive enzyme activities of the sea cucumber A postichopus japonicas Selenka. Dif ferent proportions of sweet potato tuber and stem powders(from 10% to 50%) were added into compound feeds, which were supplied to A. japonicas during a 60-day experiment. The results showed that the two sweet potato ingredients had different eff ects on the nutrient contents of the sea cucumber body wall. The group supplied with feed containing 20% sweet potato tuber powder(T2) had the highest level of crude protein in body walls(P 0.05). In all the groups fed with powdered sweet potato tubers(T groups), the proportions of glutamic acid and lysine in body walls were higher than those in the control, whereas the proportion of methionine decreased slightly. Diff erent proportions of sweet potato ingredients in compound feeds also af fected digestive enzyme activities in the sea cucumbers. The activities of protease and lipase first increased and then gradually decreased with increasing proportions of sweet potato materials in the feed. The highest protease activity was in the T2 and the group and the highest lipase activity was in the 10% sweet potato stem(S1) group. These results show that feed components can stimulate digestive enzyme activities in sea cucumber, and that the proportions of tubers and stems of sweet potato in feed can be adjusted to improve the digestion and growth of A. japonicas in marine farms.

关键词： Apostichopus japonicas Selenka sweet potato body composition digestive enzymes

Seasonal change in body length of important small copepods and relationship with environmental factors in Jiaozhou Bay, China

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Chinese Journal of Oceanology and Limnology 2012年第3期30卷 404-409页

作者：孙晓红孙松李超伦王敏晓 Key Laboratory of Marine Ecology and Environmental Sciences Institute of OceanologyChinese Academy of Sciences Ocean College Shandong University at Weihai Jiaozhou Bay Marine Ecosystem Research station Institute of OceanologyChinese Academy of Sciences

Differences among species in prosome length and in species' response to environmental factors do exist. Therefore, it is useful to examine prosome length for different copepod species in variable environments. Seasonal variations in prosome length of four small copepods and their copepodite stages in the Jiaozhou Bay were compared and the relative influence of temperature, salinity, and chlorophyll concentration were examined. Two peaks were found in the mean prosome length of Paracalanus parvus (in early winter and May). For Acartia bifilosa, the maximum values of all copepodites occurred mainly from February to April, and decreased to the bottom in July. Prosome length of Acartia pacifica peaked when it first appeared in June, then reached to the minimum in July. Parvocalanus crassirostris only appeared from late summer to autumn and the mean prosome length showed no clear changes. Correlations of adult prosome length with environmental factors were evaluated. For the four species, temperature was negatively correlated to prosome length except for P. crassirostris. But the different species varied markedly in their responds to temperature. A. bifilosa showed a more definite trend of size variation with temperature than P. parvus and A. pacifica. Correlations of prosome length with salinity were significantly positive for almost all the small copepods. The relationship between chlorophyll concentration and prosome length was complicated for these copepods, but for P. parvus, chlorophyll concentration was also an important affecting factor. Furthermore, investigation needs to be done on food quality for some copepod. These results are essential to estimate the biomass and the production, and to understand these small copepods' population dynamics in this human-affected bay.

关键词： small copepod prosome length copepodites environmental factors Jiaozhou Bay

Evaluating the eff ect of input variables on quantifying the spatial distribution of croaker Johnius belangerii in Haizhou Bay,China

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Journal of Oceanology and Limnology 2021年第4期39卷 1570-1583页

作者： Yunlei ZHANG Ying XUE Binduo XU Chongliang ZHANG Xiaoxiao ZAN College of Fisheries Ocean University of ChinaQingdao 266003China Marine College Shandong UniversityWeihai 264209China Field Observation and Research station of Haizhou Bay Fishery Ecosystem Ministry of EducationQingdao 266003China

A habitat model has been widely used to manage marine species and analyze relationship between species distribution and environmental *** predictive skill in habitat model depends on whether the models include appropriate explanatory *** to limited habitat range,low density,and low detection rate,the number of zero catches could be very large even in favorable *** zeroes will increase the bias and uncertainty in estimation of ***,appropriate explanatory variables need to be chosen first to prevent underestimate or overestimate species abundance in habitat *** addition,biotic variables such as prey data and spatial autocovariate(SAC)of target species are often ignored in species distribution ***,we evaluated the eff ects of input variables on the performance of generalized additive models(GAMs)under excessive zero catch(>70%).Five types of input variables were selected,i.e.,(1)abiotic variables,(2)abiotic and biotic variables,(3)abiotic variables and SAC,(4)abiotic,biotic variables and SAC,and(5)principal component analysis(PCA)based abiotic and biotic variables and ***’s croaker Johnius belangerii is one of the dominant demersal fish in Haizhou Bay,with a large number of zero catches,thus was used for the case *** show that the PCA-based GAM incorporated with abiotic and biotic variables and SAC was the most appropriate model to quantify the spatial distribution of the *** variables and SAC were important and should be incorporated as one of the drivers to predict species *** study suggests that the process of input variables is critical to habitat modelling,which could improve the performance of habitat models and enhance our understanding of the habitat suitability of target species.

关键词： generalized additive model principal component analysis biotic variables spatial autocovariate