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基于迭代Reference Governor的自由活塞发动机活塞运动控制 被引量:2
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作者 宫洵 胡云峰 +1 位作者 杨荣彬 陈虹 《控制理论与应用》 EI CAS CSCD 北大核心 2017年第2期188-196,共9页
精确的活塞运动控制是实现自由活塞发动机(free piston engine,FPE)安全可靠运行的前提,本文的主要研究内容是带有约束的FPE活塞运动控制.根据活塞运动控制问题描述,建立了FPE面向控制的非线性离散模型;设计状态反馈控制器,通过控制循... 精确的活塞运动控制是实现自由活塞发动机(free piston engine,FPE)安全可靠运行的前提,本文的主要研究内容是带有约束的FPE活塞运动控制.根据活塞运动控制问题描述,建立了FPE面向控制的非线性离散模型;设计状态反馈控制器,通过控制循环喷油量使活塞运动位置跟踪期望值;针对电磁负载变化引起的活塞运动瞬态波动超出安全约束的问题,考虑闭环系统非线性隐式的特点,在不改变原状态反馈控制的框架下,提出基于牛顿迭代的Reference Governor来调节负载,保证系统运动满足安全约束.所提出的控制方法为带有约束FPE活塞运动控制提供解决方案的同时,扩展了Reference Governor算法在隐式系统的应用.通过MATLAB与AMESim联合仿真验证了控制方法的有效性. 展开更多
关键词 自由活塞发动机 活塞运动控制 Referencegovernor 约束
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Present Status of Solid Waste Management at Babylon Governorate, Iraq 被引量:5
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作者 Ali Chabuk Nadhir Al-Ansari +2 位作者 Hussain Musa Hussain Sven Knutsson Roland Pusch 《Engineering(科研)》 2015年第7期408-423,共16页
Babylon Governorate covers an area of 5315 km2 with a population that reaches about 1,974,490 inhabitants in the central part of Iraq. Iraq produced 31,000 tons/day solid waste in 2013. The Governorate of Babylon prod... Babylon Governorate covers an area of 5315 km2 with a population that reaches about 1,974,490 inhabitants in the central part of Iraq. Iraq produced 31,000 tons/day solid waste in 2013. The Governorate of Babylon produces annual 483,221 tons of solid waste. Management of collection and disposal of waste in Babylon Governorate is done through open dumping of waste and poor collection process. These sites do not conform to the scientific and environmental criteria applied in the selection of landfill sites. To find out how much solid waste is expected in the future, two methods were used to calculate the population growth in Babylon Governorate to the year 2030. The results showed that the total waste in 2030 will be 761,104 tons and 943055 tons while the cumulated quantity of solid waste expected till 2030 was 12,494,521 tons and 14,095,437 tons according to the first and second methods respectively. 展开更多
关键词 BABYLON governorate SOLID WASTE MANAGEMENT WASTE DISPOSAL SITES Iraq
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CLINICAL STUDIES ON CEREBRAL INFARCTION TREATED WITHACUPUNCTURE AT ACUPOINTS OF GOVERNOR MERIDIAN 被引量:1
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作者 许能贵 张闻东 梁兴伦 《World Journal of Acupuncture-Moxibustion》 1997年第3期21-25,共5页
In this paper, 148 cases of cerebral infarction were treated with acupuncture at acupoints of Governor meridian (treatment group), and the other 97 cases were treated simultaneously with conventional body acupuncture ... In this paper, 148 cases of cerebral infarction were treated with acupuncture at acupoints of Governor meridian (treatment group), and the other 97 cases were treated simultaneously with conventional body acupuncture (control group). The results show that the marked improvement rate was 42. 6 % and the total effective rate was 96. 6 % in the treatment group; while in the control group, the marked improvement rate and the total effective rate were 28. 9 % and 89. 1 % respectively.It suggests that the therapeutic effect in the treatment group is better than that of the control group.The roles of regulation and ameliorating hemorheology of acupuncture at acupoints of Governor meridian are the foundation of its treatment mechanism. 展开更多
关键词 ACUPUNCTURE ACUPOINTS of governor MERIDIAN Cerebral INFARCTION
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Effect of Nonlinearities in Turbine Governor System on Torsional Oscillation Stability 被引量:1
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作者 于达仁 鲍文 徐基豫 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1997年第2期25-29,共5页
EfectofNonlinearitiesinTurbineGovernorSystemonTorsionalOscilationStabilityYUDaren(于达仁)BAOWen(鲍文)XUJiyu(徐基豫)... EfectofNonlinearitiesinTurbineGovernorSystemonTorsionalOscilationStabilityYUDaren(于达仁)BAOWen(鲍文)XUJiyu(徐基豫)Dept.ofPowerEngin... 展开更多
关键词 TURBINE governor NONLINEARITY torsional OSCILLATION
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A Century of Monitoring Urban Growth in Menofya Governorate, Egypt, Using Remote Sensing and Geographic Information Analysis 被引量:1
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作者 Islam Abou El-Magd Ahmed Hasan Abdelfatah El Sayed 《Journal of Geographic Information System》 2015年第4期402-414,共13页
Urban growth is a global phenomenon mainly driven by the overpopulation growth particularly in developing countries like Egypt. Pattern and extent of urban growth could be monitored and modelled on a spatial and tempo... Urban growth is a global phenomenon mainly driven by the overpopulation growth particularly in developing countries like Egypt. Pattern and extent of urban growth could be monitored and modelled on a spatial and temporal dimension. GIS and remote sensing data along with other thematic maps were used to analyze the urban growth, pattern and extent in the last century in one of the biggest governorates at the heart of the Nile Delta of Egypt. Both spatial and temporal analyses enabled to identify the pattern of urban growth and subsequently project the nature of future growth. However, the overall urban growth in the last century was 12 times the original built up areas in 1910;the third stage from 1950 to 1972 was the highest stage of urban growth with 124% increase of the built-up area. The dominant pattern of urban growth was linear along highways and railways with majority to the North, North East and North West directions. The study developed a spatial model to project urban growth by 2027, indicating that urban growth in the Menofya Governorate would be continued at the same directions with the same pattern with an estimated increase of 33%. The study provided an understanding of the controlling factors which drove the urban growth along this long time. 展开更多
关键词 URBAN Growth GIS REMOTE Sensing Modelling Menofya governorate EGYPT
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CLINICAL OBSERVATION ON TREATMENT OF 205 CASES OF CERVICAL SPONDYLOPATHY BY ACUPUNCTURE AND MOXIBUSTION ON THE GOVERNOR VESSEL OF THE NECK
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作者 龚维义 储浩然 《World Journal of Acupuncture-Moxibustion》 1996年第4期3-7,共5页
This article involves 325 patients suffering from cervical spondylopathy,amongthem 205 cases were treated by acupuncture and moxibustion on the governor vessel of the neck(treatment group),the other 120 cases were t... This article involves 325 patients suffering from cervical spondylopathy,amongthem 205 cases were treated by acupuncture and moxibustion on the governor vessel of the neck(treatment group),the other 120 cases were treated by common acupuncture(control group).Itwas observed that the cure rate,the total effective rate was 91.2%,98.5% in the treatmentgroup,and 55.8%,87.5% in the control group.There were statistically significant differences(P【0.01)in the cure rate and total effective rate between the two groups.It is concluded thatacupuncture and moxibustion on the governor vessel of the neck may improve Yang Qi circulationwithin the Dumai and promote the micro-circulation in the diseased areas.Thus it evidently in-creases the therapeutic effects. 展开更多
关键词 Cervical SPONDYLOPATHY Acup and MOX therapy governor vessel NECK
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从governor与governess的区别谈起
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作者 陆琳 《大学英语》 2004年第5期30-30,共1页
英语中有这样一些词,它们成对,且在语义上相等,只不过一个专指男性.另一个专指女性。这些词就是我们所熟悉的sex—paired words。如:host—hostess,actor-actress,husband—wife.hero—heroine等。这些词不仅在语义上相等,而... 英语中有这样一些词,它们成对,且在语义上相等,只不过一个专指男性.另一个专指女性。这些词就是我们所熟悉的sex—paired words。如:host—hostess,actor-actress,husband—wife.hero—heroine等。这些词不仅在语义上相等,而且存使用中具有对称性. 展开更多
关键词 governor GOVERNESS 区别 英语 语义 用法 词汇
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Assessment of the Hydrogeochemical Characteristics of Groundwater Resources at some Wadis in the East of El Minia Governorate,Eastern Desert,Egypt
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作者 Alzahraa Abo HABIBAH Kamal DAHAB +2 位作者 Ashraf SHABANA Samir KAMH Hekmat IBRAHIM 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2022年第3期1082-1097,共16页
The El Minia governorate lies within the Nile Valley,surrounded by calcareous plateaus to the east and west.The present study focuses on the hydrogeochemistry of the Eocene limestone aquifer at some wadis in the east ... The El Minia governorate lies within the Nile Valley,surrounded by calcareous plateaus to the east and west.The present study focuses on the hydrogeochemistry of the Eocene limestone aquifer at some wadis in the east El Minia governorate,Eastern Desert,Egypt.Hydrogeologically,two main aquifers are encountered in the study area,namely the Maghagha marly limestone and the Samalut chalky limestone aquifers.The Maghagha aquifer is composed of alternating layers of marly limestone and shale with thicknesses ranging from 3.49 m to 177.05 m and a groundwater depth ranging from 8.5 m to 59.27 m which reflects low groundwater potentiality.The groundwater salinity representing this aquifer ranges from 603.5 mg/L to 978.5 mg/L,reflecting fresh water type.Samalut aquifer is made up of chalky,cavernous and fractured limestone with thickness ranging from 30 m to 205 m and groundwater depth ranging from 9 m to 86.77 m,which indicates good groundwater potential.The groundwater salinity of the concerned aquifer ranges from 349.7 mg/L to 2043.9 mg/L,reflecting fresh to possibly brackish water types.Groundwater in the study area is of meteoric water origin;recent recharge is mainly controlled through the presence of fractures and their densities.The majority of groundwater samples in the study area are suitable for drinking and irrigation purposes. 展开更多
关键词 GROUNDWATER limestone aquifers El Minia governorate Eastern Desert
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Analysis of Nonlinear Characteristics of Turbine Governor and Its Impact on Power System Oscillation
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作者 Ge Jin Hanting Yan +2 位作者 Shaoxiang Deng Xiaomei Chen Zexiang Cai 《Energy and Power Engineering》 2013年第4期746-750,共5页
In this paper, the model of turbine governor?based on the physical principles is constituted to improve the accuracy of power system dynamic simulation, making the results of simulation consistent with the actual situ... In this paper, the model of turbine governor?based on the physical principles is constituted to improve the accuracy of power system dynamic simulation, making the results of simulation consistent with the actual situation. The unit and grid coupling model which reflects the interaction between thermal system of power plant and power system is built using EMTDC/PSCAD. The influence of nonlinear characteristics on the valve opening and the steam turbine mechanical power is also analyzed in this paper. The results of simulation show that the improper setting of parameters reflecting nonlinear characteristics of turbine governor can lead to the cyclical oscillations of the valve opening and the?steam turbine mechanical power, and even can lead to the power oscillation persistently. The research achievements in this paper have a certain reference value on exploring the causes of power oscillation from the prime mover. 展开更多
关键词 TURBINE governor MODELING NONLINEAR Characteristics Power System OSCILLATION
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Recent Activities of the Board of Governors of Acta Materialia Inc.
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《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2008年第5期389-390,共2页
July 2007-July 2008 This report highlights the actions, discussions, and the general activities of the Board of the Governors of Acta Materialia Inc. over the past year. It covers the Board
关键词 over Recent Activities of the Board of governors of Acta Materialia Inc GOLD
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Measuring the Public Awareness toward Household Waste Management in Muharraq Governorate-Kingdom of Bahrain
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作者 S. Y. Abbas K. Kirwan D. Lu 《Journal of Environmental Protection》 2020年第3期196-214,共19页
Municipal Solid Waste (MSW) generation is growing rapidly as compared to the rate of urbanization. Household waste management is considered a highly challenging task for Bahrain’s policy-makers, urban planners and mu... Municipal Solid Waste (MSW) generation is growing rapidly as compared to the rate of urbanization. Household waste management is considered a highly challenging task for Bahrain’s policy-makers, urban planners and municipalities due to rising population, burgeoning growth rate of waste generation, limited availability of land and scarce waste disposal sites. Public awareness represents a key enabler in order to succeed any sustainable waste management practice in the country. The survey aimed at gauging public awareness about household waste management in Muharraq Governorate and explored if there are any correlations between educational level, gender, occupation and age and area of living with the level of public awareness as well as its three components: knowledge, attitude and behaviour of the people in Muharraq Governorate. The results indicated the total awareness is significantly different across different age levels and nationality. Moreover, it shows a high public awareness toward household waste management among people in Muharraq Governorate, which indicated that the society is aware and has the basics to build on in terms of sustainable waste management practices and technologies adoption, which may help overcome the possible social barrier represented by low public awareness. 展开更多
关键词 PUBLIC AWARENESS Household WASTE MANAGEMENT ATTITUDE Behaviour KINGDOM of Bahrain Muharraq governorate
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Francis Turbine and Governor Improved Models Considering Step Closing Law of Guide Vanes for Power System Stability Analysis
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作者 Yuheng Tang 《Journal of Power and Energy Engineering》 2014年第9期125-131,共7页
The Francis turbine governing system models in PSD-BPA can’t precisely reflect the actual characteristics. Endeavor was done in this paper to solve the problem. An improved model of actuating mechanism was developed,... The Francis turbine governing system models in PSD-BPA can’t precisely reflect the actual characteristics. Endeavor was done in this paper to solve the problem. An improved model of actuating mechanism was developed, which could reflect the step closing characteristic of hydro guide vanes. The effect of the inflection point value of actuating mechanism on load rejection was analyzed based on simulation. The non-linear Francis turbine model with power versus gate position module was researched in this paper. Based on field test, comparisons of simulation results with measured data were presented. The analysis demonstrates that the improved models of Francis turbine and governor proposed in this paper are more realistic than the models of BPA, and can be applied in power system simulation analysis better. 展开更多
关键词 FRANCIS TURBINE governor Actuating Mechanism STEP CLOSING LAW Improved Models Power System Stability Analysis
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Impact of Islanding on Governor Signal of Distributed Resources
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作者 Mahdi Ghadiri Ali Moeini Hossein Yassami 《Journal of Electromagnetic Analysis and Applications》 2011年第2期56-64,共9页
Technical and economical impacts of distributed resources have encouraged big industry managers and distribution systems’ owners to utilize small type of electric generations. One important preventive issue to develo... Technical and economical impacts of distributed resources have encouraged big industry managers and distribution systems’ owners to utilize small type of electric generations. One important preventive issue to develop these units is islanding situation. Expert diagnosis system is needed to distinguish network cut off from normal occurrences. It should detect islanding in time to disconnect the unit and prevent any additional failures in equipment. An important part of synchronous generator is automatic load-frequency controller (ALFC). This controller is designed properly to respond to load variations and to fix frequency at constant value when working alone as an islanding system and to control output power when operating in parallel with the main. In this paper, a new approach based on monitoring ALFC re-sponse with regard to input signal to governor is introduced. Numbers of initial crossing value are introduced as an index for islanding detection. Simulation results show that input signal to governor has different characteristics in common disturbances. 展开更多
关键词 Automatic LOAD Frequency CONTROLLER Distributed Generation governor ISLANDING Detection INITIAL Value CROSSING
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Knowledge &Utilization of Long Lasting Impregnated Nets among Housewives in Al Moneera City and Al Koozi Villages, Hodieda Governorate, Republic of Yemen 2007
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作者 Nahid A. Baktayan Ali M. Assabri +1 位作者 Belquis A. Farea Arwa A. Farea 《Health》 2021年第3期306-322,共17页
Malaria is considered as one of the main health problem in the Republic of Yemen. In February 2006 National Malaria Control Program started freely distribution of Long Lasting Impregnated Nets (LLINs) for vulnerable g... Malaria is considered as one of the main health problem in the Republic of Yemen. In February 2006 National Malaria Control Program started freely distribution of Long Lasting Impregnated Nets (LLINs) for vulnerable groups to malaria infection (pregnant women and children under 5 years). After one year of distribution, there is a need to measure the use rate among vulnerable groups and explore factors affecting their use. The aim of the study was to investigate the use rate of long lasting impregnated nets among children under five years and pregnant women in Al Moneera city and Al Koozi villages of Hodieda governorate. <strong>Methodology:</strong> Cross section study with multistage sample, Random selection of one urban and one rural locality. 768 housewives were interviewed, proportionally allocated sample according to the number of vulnerable groups in each locality. Systematic random sample to select households. <strong>Results:</strong> The use rate of LLINs for vulnerable groups was 74.3% CI (71.2 - 77.4). There was no statistically significant association between the use of LLINs and residence, also with ages of housewives, occupation, type of house, but there is strong statistically significant association between use of LLINs and having correct information about how to use and to take care of them P value < 0.001, also with educational status of housewives;P value 0.03 and educational status of fathers;P value 0.01. (84%) have correct information about how to use and take care of LLINs and the main source of information was health workers who distributed them. Only 13.4% realized pregnant women as a vulnerable group to malaria infection while about 77.9% realized children as a vulnerable group to malaria infection. The main reason of LLINs use (84.8%) was protection from nuisance of insects. <strong>Conclusion and recommendations: </strong>There is shortage in the information about the protective effect of LLINs from malaria infection and the main reason of using them is protection from nuisance of insects. There is a need to increase health awareness about the role of LLINs in malaria prevention. 展开更多
关键词 Vulnerable Groups to Malaria Infection Long-Lasting Impregnated Nets (LLINs) Use Rate Housewives Al Moneera City and Al Koozi Villages Hodieda governorate Yemen
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Clinical effect of governor meridian moxibustion on treatment of lumbar disc protrusion: A meta analysis
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作者 Sheng-Yue Wen Min Zhang +8 位作者 Guo-Qing Du Jian Pang Xun Lin Ning-Yang Gao Yue-Long Cao Yu-Yun Wu Yu-Xin Zheng Bo Chen Hong-Sheng Zhan 《Journal of Hainan Medical University》 2022年第13期55-62,共8页
Objective:To explore the clinical effect of governor meridian moxibustion on lumbar intervertebral disc protrusion.Methods:Randomized controlled trials on treatment of lumbar intervertebral disc protrusion with govern... Objective:To explore the clinical effect of governor meridian moxibustion on lumbar intervertebral disc protrusion.Methods:Randomized controlled trials on treatment of lumbar intervertebral disc protrusion with governor meridian moxibustion and combined governor meridian moxibustion were retrieved from CNKI,VIP,Wan Fang Data,CBM,Web of ScienceTM Core Collection,EBSCO Medline,PubMed,OVID,the Cochrane Library,and other databases.The time was from the inception of the database until October 2021.The studies were screened according to the inclusion and exclusion criteria,extracted,and evaluated for quality assessment.The data were analyzed with Review Manager 5.3 software.Results:A total of 24 randomized controlled trials(2379 cases in total)were included.Meta-analysis results showed that compared with control groups such as acupuncture,electroacupuncture,and massage,the governor meridian treatment improved the clinical efficacy[RR=1.17,95%CI(1.13,1.20),P<0.001],relieved patients'pain[MD=-1.56,95%CI(-1.89,-1.22),P<0.001],and improved patients’dysfunction to a certain extent[MD=4.84,95%CI(3.87,5.82),P<0.001].Funnel plot analysis showed that the included literature may be potentially biased in publication.Conclusion:Governor meridian moxibustion has a significant effect on the treatment of lumbar disc protrusion and is worthy of widespread use.However,given the small number of high-quality literature included in the study,the small sample size,and the short follow-up time,high-quality randomized controlled trials are needed to further study the long-term therapeutic effect of governor meridian moxibustion. 展开更多
关键词 governor meridian moxibustion Lumbar disc protrusion META-ANALYSIS Randomized controlled trial
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SWT Microcomputer-Based Hydro-Turbine Governor
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作者 Shao Yixiang Cai Weijiang +1 位作者 Gu Yunjun CaiXiaofeng (Nanjing Automation Research Institute (NARI )Electric Control Co) 《Electricity》 1998年第4期37-39,共3页
This paper presents a new microcomputer-based hydro-turbine governor type SWT and introduces the system structure and the main function of the governor. By comparison with other governors used at present, the paper ex... This paper presents a new microcomputer-based hydro-turbine governor type SWT and introduces the system structure and the main function of the governor. By comparison with other governors used at present, the paper expounds the merits of the SWT microcomputer-based governor. 展开更多
关键词 governor state analysis COMPUTER network servo-proportion VALVE
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Parkistan Province Governor:Travel to China with Ample Fruits
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作者 Sun Yongjian 《China's Foreign Trade》 2005年第20期18-19,共2页
Mr. Khalid Maqbool, Lt. General(Retired), is the Governor of Punjab province, Parkistan, he led adelegation to visit China from September 12 to 19. During the visit, he traveled in Jiangsu, a sis-ter province of Punja... Mr. Khalid Maqbool, Lt. General(Retired), is the Governor of Punjab province, Parkistan, he led adelegation to visit China from September 12 to 19. During the visit, he traveled in Jiangsu, a sis-ter province of Punjab. "It is a very fruitful travel!" he said when interviewed by China’s Foreign Trade. 展开更多
关键词 very Parkistan Province governor
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Assessment of Indoor Radon Concentrations in Dwellings for Baghdad Governorate by Using RAD-7 Detector
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作者 Mahmood S. Karim Hasan H. Daroysh Ali N. Mohammed 《Detection》 2016年第2期40-44,共5页
In the present work, radon gas concentrations in different dwellings in Baghdad governorate are measured by using RAD-7 detector. The results have shown that, the radon gas concentrations ranged between (40.67 ± ... In the present work, radon gas concentrations in different dwellings in Baghdad governorate are measured by using RAD-7 detector. The results have shown that, the radon gas concentrations ranged between (40.67 ± 3.1 Bq/m<sup>3</sup>) to (190.00 ± 2.7 Bq/m<sup>3</sup>) with an average value (113.66 ± 30.2 Bq/m<sup>3</sup>);in the first one we draw the map radiations for indoor radon gas concentrations in Baghdad governorate. We would like to mention that the present study is considered to be very important and vital because it is concerned with people health and safety in the first place. 展开更多
关键词 RADON DWELLINGS RAD-7 Detector CR-39 Indoor Radon Concentration Baghdad governorate
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A Mirror of the Inside Story inAmerican Election──A Review of Mark Twain's "Running for Governor
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《漳州师院学报(哲学社会科学版)》 1994年第1期99-103,共5页
关键词 MARK A Mirror of the Inside Story inAmerican Election A Review of Mark Twain’s Running for governor
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INSCRIPTION BY MR. WAN XUEYUAN, GOVERNOR OF ZHEJIANG
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《中国对外贸易》 1995年第4期1-1,共1页
We are very glad to welcome honored guests from afar, and with them we makefriends in a bid to expand the magnitude of opening-up toward the prosperity ofZhejiang-Wan Xueyuan, January 1995.
关键词 WAN XUEYUAN INSCRIPTION BY MR governor OF ZHEJIANG
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