METHODS: 5 184 people of non-manual workers and manual workers in city as well as farmers at different sex, aged from 20-59 years, were selected in Shijiazhuang, Cangzhou and Chengde with random sampling of stratified cluster in July 2000. They were assigned into 20-39 year group and 40-59 years group according to age to perform investigation of their physical work, which composed of strength of grasp, anteflexion of body when sitting, standing with single foot when closing eyes, back pressure, vertical jump, 10 m×4 return run, push-up, sit-up and choice of reaction time, etc. RESULTS: 4 800 people were involved in the result analysis.

于2000-07用分層整群的隨機(jī)抽樣方法抽取石家莊、滄州国产麻豆色视频在线观看、承德3個(gè)城市不同性別的城市非體力勞動(dòng)者亚洲狼友视频在线播放、城市體力勞動(dòng)者、農(nóng)民3類職業(yè)人群的20～59歲公民5184名乱淫网站，按年齡分為20～39歲組和40～59歲組兩組国产一级媱片A片免费，對其進(jìn)行體能測查在线观看国产对白网站视频免费播放，測查內(nèi)容包括握力、坐位體前屈九九久久久免费毛片基地、閉眼單腳站立、背力男女交性高清视频无遮挡、縱跳看免费5XXAAA毛片中国、10m×4往返跑、俯臥撐欧美视频精品一区二区三区、仰臥起坐国产A片地址一、選擇反應(yīng)時(shí)等。

Methods By cluster random sampling method,a total of 21 kindergarten children in Meizhou were taken.

方法采用整群隨機(jī)抽樣的方法人人操人人干人人操，抽取梅州市21所幼兒園的全部在園兒童久久人妻Av无码中文字幕第一，采用自擬問卷和克氏行為量表進(jìn)行調(diào)查和評定。

From the RAPD analysis data, the band similarity rates and average band similarity rates between two individuals in the sampling population, average band allele frequencies, average band heterozygosis degree, and the Shannon genetic diversity index were calculated to perform the cluster analysis of heterozygosis arithmetic averages and construct the phylogenetic tree.

根據(jù)RAPD結(jié)果分別計(jì)算了兩兩個(gè)體間的帶紋相似率亚洲va在线va天堂XXxX国产、平均帶紋相似率韩国AV永久免费不卡在线、帶紋的平均等位基因頻率和平均帶紋雜合度及遺傳多樣性指數(shù)，作親緣關(guān)系的類平均聚類并繪制了相關(guān)關(guān)系聚類圖自拍偷拍欧美日本。

METHODS: A total of 1 536 people in rural areas of shaanxi were studied by cluster random sampling methods. All particants were checked by slit lamp, and the people who were more than 50 years old carried out the standard examination by internal criteria. Then they were examined by LOCS Ⅲ in mydriatic situation when there were no contraindication.

遵循按比例菠萝在线成人网站免费观看网址大全、隨機(jī)、整群抽樣的原則對陜西省洋縣 1 536人進(jìn)行白內(nèi)障患病率的橫斷面調(diào)查精品免费一区，所有受檢人員均采用裂隙燈檢查晶狀體A级黄片在线视频，年齡≥50歲的人，先在小瞳孔下按照國內(nèi)診斷標(biāo)準(zhǔn)進(jìn)行檢查喷射97人人操，如無禁忌再充分散瞳后一级一级人与动毛片免费，按LOCSⅢ標(biāo)準(zhǔn)進(jìn)行檢查。

Methods According to the classification of east, middle and west areas in China, as well as urban and rural, the multi-stage cluster probability sampling was used to select randomly total 17607 children under 5 years, whose weight and height were measured in standard method.

方法采用多階段分層整群隨機(jī)抽樣的方法欧美在线看视频，按照東在线观看永久性无码视频、中、西三類地區(qū)和城市99re热精品视频、農(nóng)村的分層原則在线观看黄色网站的视频。，在全國選取17607名5歲以下兒童，測量兒童的身高和體重99热精品2。

Firstly,the sampling design has great impact on the accuracy of remote sensing classification.There exists great randomicity on the result of points and cluster sample verification on the different Sampling design.On the same sampling design,the stability of point sample verification is higher than that of Cluster sample verification.Secondly,the average accuracy of different sampling designs of multi-point and multi-cluster sample verification can reflect the accuracy characteristic.During the course of point sample verification,stratified sampling's error is lower than others'.During the course of cluster sample verification,systematic sampling and stratified sampling's accuracy are prior to simple random sampling's.

研究結(jié)果表明：（1）抽樣方式對遙感分類精度評價(jià)結(jié)果的影響是客觀存在的91小视频国产在线，不同抽樣方式下的點(diǎn)樣本和群樣本檢驗(yàn)結(jié)果都存在一定的隨機(jī)性，但同一種抽樣方式下美女超污视频网站，點(diǎn)樣本檢驗(yàn)精度評估結(jié)果的波動(dòng)幅度小于群樣本檢驗(yàn)日韩一级欧美一级高清片w，穩(wěn)定性比群樣本檢驗(yàn)要好；（2）不同抽樣方式下的多次點(diǎn)樣本和群樣本檢驗(yàn)的平均精度檢驗(yàn)結(jié)果基本上都能夠反映分類圖像的精度特征香蕉亚洲91一本大道，其中在线亚洲国产鲁一鲁网，點(diǎn)樣本檢驗(yàn)中，分層隨機(jī)抽樣點(diǎn)樣本檢驗(yàn)效果較好；群樣本檢驗(yàn)中在线观看视频免费网站黄，系統(tǒng)抽樣群樣本檢驗(yàn)和分層隨機(jī)抽樣群樣本檢驗(yàn)的效果優(yōu)于簡單隨機(jī)抽樣群樣本檢驗(yàn)美女视频黄8频a美女大全2020。

Coil, Fe, Ni and Zn in spatial variation are identified and the correct assignations are 90.65% for three cluster sites; and (4) based on spatial variations in water quality, it is possible to optimize the monitoring strategy in future with only one of 3 sampling sites and seven discriminant parameters, which can decrease the number of sampling stations and corresponding costs.

coil， Fe特黄一级乱淫A片， Ni和Zn）可以反映整體水質(zhì)的空間差異性色色肉肉视频，且具有90.65%的正確判別能力；④歸納起來久久免费网址，從3類采樣點(diǎn)中選擇一個(gè)或多個(gè)国产精品久久永久免费、監(jiān)測7個(gè)顯著性污染指標(biāo)即可全面反映后海灣水質(zhì)管制區(qū)的水質(zhì)空間特征，實(shí)現(xiàn)水質(zhì)監(jiān)測網(wǎng)絡(luò)優(yōu)化最新中文字幕在线视频网站。

Methods Randomized cluster sampling and a selfmade questionnaire were used in an onscene investigation.

采用隨機(jī)抽樣方法日韩美女精品中文字幕在线，運(yùn)用自行設(shè)計(jì)的問卷調(diào)查表現(xiàn)場調(diào)查。

The common stressors are long working houres, short of working rest or even none of rest , bad labor environments , irrational labor institution and contradictory of social circumstances.1.2 The analysis of occupational stress900 Female workers were sampled at random with cluster sampling based on AET analysis.

1.2 職業(yè)緊張水平的研究以進(jìn)入AET分析的各工種工人為基礎(chǔ)人群在线观看中文字幕网。用整群抽樣的方法免费一级毛片在线播放女同，隨機(jī)抽取各分析工種在崗一年以上900名女工作為緊張水平的研究對象。利用OSI-R中的OSQ和PRQ問卷測試作業(yè)女工的緊張水平和應(yīng)變能力天天视频在线50页免费观看。

Methods Radom cluster sampling was used to choose 5 nursery schools,all 301 preschool children of low class were investigation object, and micronutrient measures such as serum zinc, iron, calcium and serum vitamin A were carried out.

隨機(jī)整群抽取深圳市5家托幼機(jī)構(gòu)国产成年免费在线，中、小班全體學(xué)齡前兒童3 0 1名為調(diào)查對象yiyinav，進(jìn)行血清鋅免费欧美黄色、鐵、鈣日韩欧美综合亚洲欧美、血清維生素A等微量營養(yǎng)素測量青草黄片。