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铁路车站零担中转台货棚职业危害调查
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作者 卢敏 高春英 李理 《铁道劳动安全卫生与环保》 1994年第4期263-264,共2页
对较大的中转站的零担中转台货棚进行了职业危害调查,发现环境空气中粉尘浓度超标7倍,四乙基铅浓度超标19~65倍,同时还有噪声振动存在,工人的装卸任务量大,工作时间超过10h,其根源是由于叉车以汽油为燃料,装卸时对环境... 对较大的中转站的零担中转台货棚进行了职业危害调查,发现环境空气中粉尘浓度超标7倍,四乙基铅浓度超标19~65倍,同时还有噪声振动存在,工人的装卸任务量大,工作时间超过10h,其根源是由于叉车以汽油为燃料,装卸时对环境的污染,建议零担中转台货棚内叉车装卸作业应定为职业性有害作业。 展开更多
关键词 零担中转台货棚 铁路 车站 职业危害 调查
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YK—3无线通信中转台远程遥控器
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作者 肖爱民 《中外技术情报》 1994年第1期16-17,共2页
随着通信事业的发展,超短波通信已逐步成为各系统各部门的重要通信手段之一。对于一些较大的通信网,常需要两组以上的频率工作;对于一些已有的不同频率的小网,也常需要联网。而目前的中转台只能工作在一个固定的频道上,组网中的中心台... 随着通信事业的发展,超短波通信已逐步成为各系统各部门的重要通信手段之一。对于一些较大的通信网,常需要两组以上的频率工作;对于一些已有的不同频率的小网,也常需要联网。而目前的中转台只能工作在一个固定的频道上,组网中的中心台无法通过一个中转台与不同频率的分台互通,所以有必要设计一种遥控器。 展开更多
关键词 无线通信 中转台 远程遥控器
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双马达驱动转台中框的模态与变形分析
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作者 董景龙 陶建峰 刘成良 《上海交通大学学报》 EI CAS CSCD 北大核心 2010年第8期1130-1134,1139,共6页
为了分析双马达驱动系统的输出力矩对考虑弹性的转台中框变形的影响,采用ANSYS有限元工具对转台中框进行了模态分析.利用ADAMS软件的柔性模块,基于模态的线性叠加方法,研究了双马达输出力矩在同步和不同步驱动情况下的转台中框变形响应... 为了分析双马达驱动系统的输出力矩对考虑弹性的转台中框变形的影响,采用ANSYS有限元工具对转台中框进行了模态分析.利用ADAMS软件的柔性模块,基于模态的线性叠加方法,研究了双马达输出力矩在同步和不同步驱动情况下的转台中框变形响应,分析了转台框架变形的原因.仿真结果表明,合理地施加双马达输出角加速度以及保证双马达输出完全同步转矩可以有效抑制转台中框的变形. 展开更多
关键词 双马达驱动 转台 模态分析 扭转变形
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强化管理 促进广播中波转播台稳定发展 被引量:2
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作者 王涛 《科技视界》 2015年第35期341-341,共1页
随着我国改革开放的不断深入,我国广播事业得到快速发展,并在社会政治、经济文化传播及社会生活当中都具有重要的影响,与此同时,随着新兴传播媒体的日新月异,传统的广播行业面临着新的发展机遇和挑战,如何有效实现广播行业的强化管理,... 随着我国改革开放的不断深入,我国广播事业得到快速发展,并在社会政治、经济文化传播及社会生活当中都具有重要的影响,与此同时,随着新兴传播媒体的日新月异,传统的广播行业面临着新的发展机遇和挑战,如何有效实现广播行业的强化管理,应对其中的所带来的挑战,促进广播中转台的稳定发展,特别是中波转播台的发展具有重要意义。 展开更多
关键词 广播管理 中转台 发展
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超短波对讲机通信在集团企业中的应用
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作者 赵丽攀 徐淑彦 《科技与企业》 2013年第3期115-115,共1页
在现代通信中,对讲机是一种近距离的、简单的无线传输通信工具,可随着社会的不断进步,经济的不断发展,越来越多的集团性企业成长起来,不断改变的环境对无线电对讲的困扰也是越来越多。
关键词 对讲机 中转台 信号覆盖
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无线调度通信系统在现有铁路运输中的运用
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作者 杨龙飞 《蒲白科技》 2019年第1期79-80,78,共3页
本文通过介绍铁路无线调度通信系统及其核心中转台在蒲白专用线的运用,分析了无线通信中转台提供信道中转带来的益处,阐明了无线调度通信系统在铁路安全生产提供了保障。
关键词 无线调度 中转台 信道
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冲压生产线自动化焊接系统设计
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作者 詹俊勇 王军领 仲太生 《锻压装备与制造技术》 2023年第6期54-57,共4页
通过对螺母焊接工艺的研究,提出一种冲压件自动化焊接系统解决方案,替换人工完成冲压件螺母焊接工作,实现了冲压线螺母焊接无人化生产,满足了与冲压自动化工序的对接要求。布局和规划设备部件,将布局中相互配合的设备参数进行优化筛选,... 通过对螺母焊接工艺的研究,提出一种冲压件自动化焊接系统解决方案,替换人工完成冲压件螺母焊接工作,实现了冲压线螺母焊接无人化生产,满足了与冲压自动化工序的对接要求。布局和规划设备部件,将布局中相互配合的设备参数进行优化筛选,提升了焊接速度节拍,降低了高强度人工劳动工作量,为冲压件自动化焊接生产线顺利实施提供借鉴和样板。 展开更多
关键词 冲压生产线 焊接系统 存放库 中转台
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Effect of sputtering conditions on growth and properties of ZnO :Al films
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作者 石倩 代明江 +3 位作者 林松盛 侯惠君 韦春贝 胡芳 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第5期1517-1524,共8页
Al-doped zinc oxide(AZO) films were deposited on glass substrates by mid-frequency magnetron sputtering. The effects of substrate rotation speed and target-substrate distance on the electrical, optical properties an... Al-doped zinc oxide(AZO) films were deposited on glass substrates by mid-frequency magnetron sputtering. The effects of substrate rotation speed and target-substrate distance on the electrical, optical properties and microstructure and crystal structures of the resulting films were investigated by scanning electron microscopy(SEM), atomic force microscopy(AFM), X-ray diffraction(XRD), spectrophotometer and Hall-effect measurement system, respectively. XRD results show that all AZO films exhibit a strong preferred c-axis orientation. However, the crystallinity of films decreases with the increase of substrate rotation speed, accompanying with the unbalanced grains grows. For the films prepared at different target-substrate distances, the uniform microstructure and morphology are observed. The highest carrier concentration of 5.9×1020 cm-3 and Hall mobility of 13.1 cm^2/(V·s) are obtained at substrate rotation speed of 0 and target-substrate distance of 7 cm. The results indicate that the structure and performances of the AZO films are strongly affected by substrate rotation speed. 展开更多
关键词 ZnO thin film mid-frequency magnetron sputtering substrate rotation speed target-substrate distance optoelectronic performance
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厦门电力无线电单频同播通信调度网建设
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作者 林树 《机电信息》 2010年第12期117-117,123,共2页
厦门电力调度抢修系统要求有一个能覆盖全市的无线电通信网,若以集群系统的通信方式或一般的常规中转方式来满足这样大面积的通信,存在不少技术问题并需要大量的资金投入,而无线电单频同播网却十分适合这一需求。简要介绍了同播网的原... 厦门电力调度抢修系统要求有一个能覆盖全市的无线电通信网,若以集群系统的通信方式或一般的常规中转方式来满足这样大面积的通信,存在不少技术问题并需要大量的资金投入,而无线电单频同播网却十分适合这一需求。简要介绍了同播网的原理及应用。 展开更多
关键词 单频同播 数字链路 监控 发射机 中转台
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BOOMBOX、LSS和KG510在Lotus区块的联合应用
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作者 农耀建 代伟明 +1 位作者 罗利彬 于洪玉 《物探装备》 2022年第6期361-365,共5页
本文从有效解决复杂地表区域地震勘探无线通讯目的出发,讨论了BOOMBOX与428XL仪器的联机问题,提出了三种工作方式及其混合使用的方法。并讨论了使用KG510转发站建立无线中转扫描网络等方法,以及联合使用这些设备进行地震勘探的排列检查... 本文从有效解决复杂地表区域地震勘探无线通讯目的出发,讨论了BOOMBOX与428XL仪器的联机问题,提出了三种工作方式及其混合使用的方法。并讨论了使用KG510转发站建立无线中转扫描网络等方法,以及联合使用这些设备进行地震勘探的排列检查、警戒和爆炸等作业的方法。通过这些设备的联合应用,有效提高了地震勘探施工效率。 展开更多
关键词 BOOMBOX 428XL地震仪 LSS有线放炮系统 KG510中转台
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石化厂无线通信分类简述
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作者 罗楠 王晓菡 杨晓光 《通信电源技术》 2020年第7期234-236,240,共4页
无线通信系统是信息化建设的一部分,由于它的及时、可靠及灵活性等特点,在能源化工厂区的生产、巡检、调度等众多部门有着广泛的应用,尤其在应急救援、火灾抢险等方面发挥着重要的作用。本文总结了无线通信方式在石化厂内设计的4种方式... 无线通信系统是信息化建设的一部分,由于它的及时、可靠及灵活性等特点,在能源化工厂区的生产、巡检、调度等众多部门有着广泛的应用,尤其在应急救援、火灾抢险等方面发挥着重要的作用。本文总结了无线通信方式在石化厂内设计的4种方式,然后展望了专网无线通信在工厂一体化平台建设中的作用。 展开更多
关键词 无线通信 中转台 MPT集群通信
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A community-based epidemiological study of elevated serum alanine aminotransferase levels in Kinmen, Taiwan 被引量:3
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作者 Chi-MingLiu Tao-HsinTung +4 位作者 Jorn-HonLiu VictorTze-KaiChen Ching-HengLin Chung-TeHsu PesusChou 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第11期1616-1622,共7页
AIM: To explore any gender-related differences in prevalence of and condition-associated factors related to an elevated serum alanine aminotransferase (ALT) level amongst residents of Kinmen, Taiwan. METHODS: A total ... AIM: To explore any gender-related differences in prevalence of and condition-associated factors related to an elevated serum alanine aminotransferase (ALT) level amongst residents of Kinmen, Taiwan. METHODS: A total of 11 898 of a potential 20 112 regional residents aged 30 years or more completed a related questionnaire that was carried out by the Yang-Ming Crusade between 1991 and 1994 inclusively, with blood samples being collected by public nurses. The overall questionnaire response rate was 59.3% (52.4% for males and 66.0% for females). RESULTS: The prevalence of an elevated serum ALT level for this sub-population was found to be 7.2%, the prevalence revealing a statistically significant decrease with increasing population age (P<0.0001). Males exhibited a greater prevalence of elevated serum ALT level than did females (9.4% vs 5.3%, P<0.0001). Using multiple logistic regression analysis, in addition to male gender, a younger age, greater waist circumference, presence of type-2 diabetes and hyperuricemia were the significant factors associated with an elevated serum ALT level for both males and females. Gender-related differences as regards associated factors were also revealed. For males, obesity was significantly related to an elevated serum ALT level (OR = 1.28, 95%CI: 1.00-1.66) but this was not so for females (OR = 1.09, 95%CI: 0.84-1.42). Hypertriglyceridemia (OR = 1.80, 95%CI: 1.36-2.39) and hyperuricemia (OR = 1.61, 95%CI: 1.03-2.52) were significantly related to elevated serum ALT levels only for females. CONCLUSION: Several gender-related differences were noted pertaining to the prevalence of and relationship between obesity, hypertriglyceridemia and hyperuricemia and elevated serum ALT level in the present study. 展开更多
关键词 Alanine aminotransferase PREVALENCE Community-based study Gender difference
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Polymorphisms of uridine-diphosphoglucuronosyltransferase 1A7 gene in Taiwan Chinese 被引量:2
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作者 May-Jen Huang Sien-Sing Yang +1 位作者 Min-Shung Lin Ching-Shan Huang 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第6期797-802,共6页
AIM: Single nucleotide polymorphisms (SNPs) of uridinediphosphoglucuro -nosyltransferase 1A7 (UGT1A7) gene are associated with the development of orolaryngeal cancer, hepatocellular carcinoma, and colorectal cancer. W... AIM: Single nucleotide polymorphisms (SNPs) of uridinediphosphoglucuro -nosyltransferase 1A7 (UGT1A7) gene are associated with the development of orolaryngeal cancer, hepatocellular carcinoma, and colorectal cancer. We performed this research to establish the techniques for determining UGT1A7 gene and basic data of this gene for Taiwan Chinese. METHODS: We collected blood samples from 112 healthy adults and 505 subjects carrying different genotypes of UGT1A1, and determined the promoter area and the entire sequence of UGT1A7 exon 1 by polymerase chain reaction. We designed appropriate primers and restriction enzymes to detect variant UGT1A7 genotypes found in the study subjects. RESULTS: Six SNPs at nucleotides 33, 387, 391, 392, 622, and 756 within the coding region of UGT1A7 exon 1 were found. The incidence of UGT1A7*l/*2 (N129R131W208/ K129K131W208) was predominant (35.7%) while that of UGT1A7 *3/*3 (K129K131R208/K129K131R208) was the least (2.7%). The allele frequency of UGT1A7*3, which exists in a considerable proportion of Caucasians (0.361) and Japanese (0.255), was identified only to be 0.152 in our study subjects. A novel variation at nucleotide -57 in the upstream was found, which was associated with SNPs at nucleotides 33, 387, 391, 392, and 622 in one of the variant haplotypes. The nucleotide changes at positions 387, 391, 392 and 756 were in linkage in another variant haplotype. The allele frequency of UGT1A7*3 was 0.018, 0.158, 0.242, 0.433, and 0.920 in subjects carrying wild, A(TA)6TAA/A(TA)7TAA, A(TA)7TAA/A(TA)7TAA, 211G/211A, and 211A/211A variants of UGT1A1 gene, respectively. By using natural or mutagenesis primers, we successfully detected the variations at nucleotides -57, 33, 387, and 622 with the restriction enzymes HpyCH4 Ⅳ, TaqⅠ, AflⅡ, and Rsa Ⅰ, respectively. CONCLUSION: The results indicate that the allele frequencies of UGT1A7 gene in Taiwan Chinese are different from those in Caucasians and Japanese. Carriage of the nucleotide 211- variant UGT1A gene is highly associated with UGT1A7*3. The restriction-enzymedigestion method for the determination of nucleotides-57 (or 33, or 622) and 387 can rapidly identify genotypes of UGT1A7 in an individual. 展开更多
关键词 UGT1A7 gene Single nudeotide polymorphisms GENOTYPE Taiwan Chinese
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Driving Mechanism of Cultivated Land Transition in Yantai Proper,Shandong Province,China 被引量:5
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作者 QIN Weishan ZHANG Yifeng LI Guangdong 《Chinese Geographical Science》 SCIE CSCD 2015年第3期337-349,共13页
Cultivated land transition and its driving mechanism are the hotspots among studies on land use change. In this study, we constructed a framework to study the driving mechanism of cultivated land transition from the q... Cultivated land transition and its driving mechanism are the hotspots among studies on land use change. In this study, we constructed a framework to study the driving mechanism of cultivated land transition from the quantitative perspective. Based on the vector data of land use in 1990, 2000 and 2009 of Yantai Proper, Shandong Province China, 11 explanatory variables were chosen from two aspects: the elevation, slope, cost distance to major water area and cost distance to minor water area, which presented physical factors; cost distance to district center, cost distance to town center, cost distance to city expansion center, cost distance to major roads, cost distance to city roads, cost distance to county roads and cost distance to rural roads, which presented the socio-economic factors. Combined with spatial analysis tools and Logistic regression analysis model, we construct Logistic regression analyses with four objectives that were urban construction land, rural residential land, orchard and other lands. The results show that, cost distance to district center, cost distance to town center, cost distance to city expansion center and cost distance to city roads are the significant explanatory variables for the transition of cultivated land into urban construction land. The main explained factors on the transition of cultivated land into rural residential land are slope, cost distance to town center, cost distance to county roads and cost distance to rural roads. Slope, cost distance to minor water area, cost distance to town center, cost distance to county roads and cost distance to rural roads are the significant explanatory variables for the transition of cultivated land into orchard land. Elevation, slope, cost distance to major water area and cost distance to minor water area are the main explanatory variables on the transition of cultivated land into other land uses. 展开更多
关键词 cultivated land use transition driving mechanism Yantai Proper China
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