目的通过比较80 k Vp与120 k Vp管电压下双下肢CT血管成像(CTA)扫描的辐射剂量、图像质量,评价低管电压下腹主动脉及下肢动脉CTA扫描的可行性。方法回顾性研究40例患者,随机分成两组,每组20人,分别使用80 k Vp或120 k Vp管电压进行腹主...目的通过比较80 k Vp与120 k Vp管电压下双下肢CT血管成像(CTA)扫描的辐射剂量、图像质量,评价低管电压下腹主动脉及下肢动脉CTA扫描的可行性。方法回顾性研究40例患者,随机分成两组,每组20人,分别使用80 k Vp或120 k Vp管电压进行腹主动脉及双下肢动脉CTA扫描,通过定性和定量评价轴位、三维重建图像,并进行Shapiro-Wilk Normal分布检验和独立样本t检验。通过测量腹主动脉、双侧髂总动脉、股总动脉、股浅动脉、腘动脉和胫腓干的CT值并计算对比噪声比(CNR),并评价图像质量。结果 80 k Vp管电压组的血管CT值在538 HU至605 HU,高于120 k Vp管电压组。两组之间的CNR和定性评价没有差异。80 k Vp管电压组的DLP为(203±22)m Gy·cm,120 k Vp管电压组为(780±85)m Gy·cm,有效剂量下降了74%。结论低管电压联合自动管电流调节技术进行腹主动脉及双下肢动脉CTA扫描时可以在降低辐射剂量的同时保证图像质量。展开更多
Indoor temperature is a critical environmental factor for piglets that affects the health,welfare,and production efficiency of domesticated pigs.However,there are limited reports about wireless intelligent thermal con...Indoor temperature is a critical environmental factor for piglets that affects the health,welfare,and production efficiency of domesticated pigs.However,there are limited reports about wireless intelligent thermal control and management system for piglets in largescale pig farms,and evaluation energy saving.This paper presents an Automatic Thermal Control and Management System(ATCMS)of micro-environment for piglets,that could provide a suitable production environment and reduce the energy consumption.ATCMS includes automatic temperature control system(ATCS),multipoint temperature management system(MTMS)and remote access.The infrared heating lamps are chosen in the ATCS for their good performance in heating rate and heating distribution.In order to meet a scientific temperature requirements of piglet growth,the suitable thermal ranges of each growth-stage(STREG)are employed as intelligent control strategies to generate an automatic and precise heating control.MTMS is responsible for communicating with ATCSs and transmitting information to database server for record based on wireless technology.Remote access offers information services for remote administrators by smart phones and clients via Internet.The experiments of ATCMS were carried out both in winter and summer at Binsheng Breeding Piggery Farm,Acheng City,Heilongjiang Province,China.Results showed that the temperature provided by ATCS had been kept in STREG of piglets during the whole winter period.When the indoor temperature during summer period were in or above STREG,heating lamps were turned off by ATCS for a long time.The energy consumption of ATCS were 63.60%in winter and 39.35%in summer with continuous heating system operation.Therefore,ATCMS could take the suitable thermal ranges of each growth-stage as an intelligent control principle to give an automatic and precise control to heating devices in order to meet a scientific temperature requirements of piglet growth.展开更多
文摘目的通过比较80 k Vp与120 k Vp管电压下双下肢CT血管成像(CTA)扫描的辐射剂量、图像质量,评价低管电压下腹主动脉及下肢动脉CTA扫描的可行性。方法回顾性研究40例患者,随机分成两组,每组20人,分别使用80 k Vp或120 k Vp管电压进行腹主动脉及双下肢动脉CTA扫描,通过定性和定量评价轴位、三维重建图像,并进行Shapiro-Wilk Normal分布检验和独立样本t检验。通过测量腹主动脉、双侧髂总动脉、股总动脉、股浅动脉、腘动脉和胫腓干的CT值并计算对比噪声比(CNR),并评价图像质量。结果 80 k Vp管电压组的血管CT值在538 HU至605 HU,高于120 k Vp管电压组。两组之间的CNR和定性评价没有差异。80 k Vp管电压组的DLP为(203±22)m Gy·cm,120 k Vp管电压组为(780±85)m Gy·cm,有效剂量下降了74%。结论低管电压联合自动管电流调节技术进行腹主动脉及双下肢动脉CTA扫描时可以在降低辐射剂量的同时保证图像质量。
基金陈力主持的国家哲学社会科学基金项目"我国南极权益维护的法律保障研究"(项目批准号:11BFX141)中美富布莱特项目(2012-2013)Antarctic Governance and the US-China Cooperation Under the Antarctic Treaty System+1 种基金国家重大专项"南北极环境综合考察项目--极地国家利益战略评估专题"(2011-2015)之2011年子课题"南极法律属性与南极权属的相互制约和影响"的阶段性成果屠景芳主持的国家海洋局青年海洋科学基金项目"南极法律地位面临的挑战与中国应对"的阶段性成果
基金supported by the project of National Natural Science Foundation of China(NSFC)(32072787)the project of scholar plan at Northeast Agriculture University(19YJXG02),China+1 种基金the Earmarked Fund for China Agriculture Research System(CARS-35),Chinathe Key Laboratory of Swine Facilities Engineering,Ministry of Agriculture,P.R.China.
文摘Indoor temperature is a critical environmental factor for piglets that affects the health,welfare,and production efficiency of domesticated pigs.However,there are limited reports about wireless intelligent thermal control and management system for piglets in largescale pig farms,and evaluation energy saving.This paper presents an Automatic Thermal Control and Management System(ATCMS)of micro-environment for piglets,that could provide a suitable production environment and reduce the energy consumption.ATCMS includes automatic temperature control system(ATCS),multipoint temperature management system(MTMS)and remote access.The infrared heating lamps are chosen in the ATCS for their good performance in heating rate and heating distribution.In order to meet a scientific temperature requirements of piglet growth,the suitable thermal ranges of each growth-stage(STREG)are employed as intelligent control strategies to generate an automatic and precise heating control.MTMS is responsible for communicating with ATCSs and transmitting information to database server for record based on wireless technology.Remote access offers information services for remote administrators by smart phones and clients via Internet.The experiments of ATCMS were carried out both in winter and summer at Binsheng Breeding Piggery Farm,Acheng City,Heilongjiang Province,China.Results showed that the temperature provided by ATCS had been kept in STREG of piglets during the whole winter period.When the indoor temperature during summer period were in or above STREG,heating lamps were turned off by ATCS for a long time.The energy consumption of ATCS were 63.60%in winter and 39.35%in summer with continuous heating system operation.Therefore,ATCMS could take the suitable thermal ranges of each growth-stage as an intelligent control principle to give an automatic and precise control to heating devices in order to meet a scientific temperature requirements of piglet growth.