This paper highlights the role of automation technologies for improving the safety, productivity, and environmental sustainability of underground coal mining processes. This is accomplished by reviewing the impact tha...This paper highlights the role of automation technologies for improving the safety, productivity, and environmental sustainability of underground coal mining processes. This is accomplished by reviewing the impact that the introduction of automation technology has made through the longwall shearer automation research program of Longwall Automation Steering Committee(LASC). This result has been achieved through close integration of sensing, processing, and control technologies into the longwall mining process. Key to the success of the automation solution has been the development of new sensing methods to accurately measure the location of longwall equipment and the spatial configuration of coal seam geology. The relevance of system interoperability and open communications standards for facilitating effective automation is also discussed. Importantly, the insights gained through the longwall automation development process are now leading to new technology transfer activity to benefit other underground mining processes.展开更多
Presented is a multiple model soft sensing method based on Affinity Propagation （AP）, Gaussian process （GP） and Bayesian committee machine （BCM）. AP clustering arithmetic is used to cluster training samples acco...Presented is a multiple model soft sensing method based on Affinity Propagation （AP）, Gaussian process （GP） and Bayesian committee machine （BCM）. AP clustering arithmetic is used to cluster training samples according to their operating points. Then, the sub-models are estimated by Gaussian Process Regression （GPR）. Finally, in order to get a global probabilistic prediction, Bayesian committee mactnne is used to combine the outputs of the sub-estimators. The proposed method has been applied to predict the light naphtha end point in hydrocracker fractionators. Practical applications indicate that it is useful for the online prediction of quality monitoring in chemical processes.展开更多
The International Committee of Medical Journal Editors （ICMJE） believes that there is an ethical obligation to responsibly share data generated by interventional clinical trials because participants have put themsel...The International Committee of Medical Journal Editors （ICMJE） believes that there is an ethical obligation to responsibly share data generated by interventional clinical trials because participants have put themselves at risk. In a growing consensus, many funders around the world - foundations, government agencies, and industry - now mandate data sharing. Here, we outline ICMJE＇s proposed requirements to help meet this obligation. We encourage feedback on the proposed requirements. Anyone can provide feedback at www. icmje.org by April 18, 2016.展开更多
Background:Patients with hepatocellular carcinoma(HCC)undergoing surgical resection still have a high 5-year recurrence rate(~60%).With the development of laparoscopic hepatectomy(LH),few studies have compared the eff...Background:Patients with hepatocellular carcinoma(HCC)undergoing surgical resection still have a high 5-year recurrence rate(~60%).With the development of laparoscopic hepatectomy(LH),few studies have compared the efficacy between LH and traditional surgical approach on HCC.The objective of this study was to establish a nomo-gram to evaluate the risk of recurrence in HCC patients who underwent LH.Methods:The clinical data of 432 patients,pathologically diagnosed with HCC,underwent LH as initial treatment and had surgical margin>1 cm were collected.The significance of their clinicopathological features to recurrence-free survival(RFS)was assessed,based on which a nomogram was constructed using a training cohort(n=324)and was internally validated using a temporal validation cohort(n=108).Results:Hepatitis B surface antigen(hazard ratio[HR],1.838;P=0.044),tumor number(HR,1.774;P=0.003),tumor thrombus(HR,2.356;P=0.003),cancer cell differentiation(HR,0.745;P=0.080),and microvascular tumor invasion(HR,1.673;P=0.007)were found to be independent risk factors for RFS in the training cohort,and were used for con-structing the nomogram.The C-index for RFS prediction in the training cohort using the nomogram was 0.786,which was higher than that of the 8th edition of the American Joint Committee on Cancer TNM classification(C-index,0.698)and the Barcelona Clinic Liver Cancer staging system(C-index,0.632).A high consistency between the nomogram prediction and actual observation was also demonstrated by a calibration curve.An improved predictive benefit in RFS and higher threshold probability of the nomogram were determined by receiver operating characteristic curve analysis,which was also confirmed in the validation cohort compared to other systems.Conclusions:We constructed and validated a nomogram able to quantify the risk of recurrence after initial LH for HCC patients,which can be clinically implemented in assisting the planification of individual postoperative surveil-lance protocols.展开更多
当前数字电视发展速度很快,在个别地方甚至已经开始逐步普及,但是由于经济,技术等原因,在电视广播领域,模拟电视广播还将在很长一段时间内占据主导地位.在不改变现有模拟电视广播系统的条件下,如何有效的提高视频图像的质量已经成为一...当前数字电视发展速度很快,在个别地方甚至已经开始逐步普及,但是由于经济,技术等原因,在电视广播领域,模拟电视广播还将在很长一段时间内占据主导地位.在不改变现有模拟电视广播系统的条件下,如何有效的提高视频图像的质量已经成为一个热门的话题.将数字解码技术用在改善传统的模拟电视广播质量上,用数字方法提高模拟视频的图像质量,和传统的模拟视频解码相比,解码性能较高,并且为后端数字视频处理提供优质视频源.对于模拟视频信号的解码系统,亮色分离和色度解调是视频解码的两个关键点.对于NTSC(national television system committee)制式的视频解码,当前已有的几种优质的解码算法中,亮色分离均用3D自适应梳状滤波,色度解调采用数字锁相环,均能实现优质的视频解码效果,但其共同点为算法复杂,硬件实现难度大,成本高.本文在深入研究NTSC制式编解码的基础上提出一种精简高效的数字解码方法,将传统的NTSC制式彩色全电视信号,通过高速高分辨率的FPGA(field programmable gate array)硬件采集系统转化为数字视频流,提出一种改进型自适应2D梳状滤波器进行亮色分离,相比3D梳状滤波器,在满足视频解码质量需要的基础上大幅度简化了算法,利用相位估计法恢复色同步副载波,相比数字锁相环,除简化了算法外,还避免了数字锁相环偶尔失锁的可能,且对前端视频数字化采集的采样率无特殊要求.解码后的视频分量信号可在数字视频设备上直接显示,并可为后端的数字视频图像处理等提供优质的数字视频信号源.该解码算法在MATLAB上模拟,具有解码后的图像质量良好,运算速度快和解码系统精简等特点.展开更多
Objective:To develop the missing link between hyperuricemia and hypertension.Methods:The study was conducted in Department of Biochemistry in collaboration with Nephrology Unit of Internal Medicine Department.Hyperten...Objective:To develop the missing link between hyperuricemia and hypertension.Methods:The study was conducted in Department of Biochemistry in collaboration with Nephrology Unit of Internal Medicine Department.Hypertension was defined according to blood pressure readings by definitions of the Seventh Report of the Joint National Committee.Totally 205newly diagnosed and untreated essential hypertensive cases and age-sex matched nonnotensive controls were enrolled in the study.The potential confounding factors of hyperuricemia and hypertension in both cases and controls were controlled.Uric acid levels in all participants were analyzed.Results:Renal function between newly diagnosed hypertensive cases and nonnotensive healthy controls were adjusted.The mean serum uric acid observed in newly diagnosed hypertensive cases and in nonnotensive healthy controls were(290.05±87.03)μmol/L and(245.24±09.38)μmol/L respectively.A total of 59(28.8%)participants of cases and 28(13.7%)participants of controls had hyperuricemia(odds ratio 2.555(95%CI:1.549-4.213),P<0.00l).Conclusions:The mean serum uric acid leveb and number of hyperuricemic subjects were found to be significantly higher in cases when compared to controls.展开更多
2017年,美国癌症联合会（American joint committee on cancer,AJCC）对甲状腺癌的TNM临床分期进行了调整,降低了17%的低危患者的临床分期,这部分患者多具有年轻化的特点,因此美容需求高。全腔镜甲状腺癌功能性颈淋巴结清扫具有较好的...2017年,美国癌症联合会（American joint committee on cancer,AJCC）对甲状腺癌的TNM临床分期进行了调整,降低了17%的低危患者的临床分期,这部分患者多具有年轻化的特点,因此美容需求高。全腔镜甲状腺癌功能性颈淋巴结清扫具有较好的美容效果,对患者心理的创伤较小;针式辅助技术可降低手术难度。在腔镜甲状腺手术中,展开更多
Background： Current understanding of tumor biology suggests that breast cancer is a group of diseases with different intrinsic molecular subtypes. Anatomic staging system alone is insufficient to provide future outco...Background： Current understanding of tumor biology suggests that breast cancer is a group of diseases with different intrinsic molecular subtypes. Anatomic staging system alone is insufficient to provide future outcome information. The American Joint Committee on Cancer （AJCC） expert panel updated the 8th edition of the staging manual with prognostic stage groups by incorporating biomarkers into the anatomic stage groups. In this study, we retrospectively analyzed the data from our center in China using the anatomic and prognostic staging system based on the AJCC 8th edition staging manual. Methods： We reviewed the data from January 2008 to December 2014 for cases with Luminal B Human Epidermal Growth Factor Receptor 2 （HER2）-negative breast cancer in our center. All cases were restaged using the AJCC 8th edition anatomic and prognostic staging system. The Kaplan-Meier method and log-rank test were used to compare the survival differences between different subgroups. SPSS software version 19.0 （IBM Corp., Armonk, NY, USA） was used for the statistical analyses. Results： This study consisted of 796 patients with Luminal B HER-negative breast cancer. The 5-year disease-free survival （DFS） of 769 Stage I-III patients was 89.7%, and the 5-year overall survival （OS） of all 796 patients was 91.7%. Both 5-year DFS and 5-year OS were significantly different in the different anatomic and prognostic stage groups, There were 372 cases （46.7%） assigned to a different group. The prognostic Stage II and III patients restaged from anatomic Stage III had significant differences in 5-year DFS （v2 = 11.319; P = 0.001） and 5-year OS （χ2 = 5.225, P = 0.022）. In addition, cases restaged as prognostic Stage I, II, or III from the anatomic Stage II group had statistically significant differences in 5-year DFS （χ2 = 6.510, P = 0.039） but no significant differences in 5-year OS （χ2 = 5.087, P = 0.079）. However, the restaged prognostic Stage I and II cases from anatomic Stage I had no statis展开更多
In consultative committee for space data systems（CCSDS） file delivery protocol（CFDP） recommendation of reliable transmission,there are no detail transmission procedure and delay calculation of prompted negative ac...In consultative committee for space data systems（CCSDS） file delivery protocol（CFDP） recommendation of reliable transmission,there are no detail transmission procedure and delay calculation of prompted negative acknowledge and asynchronous negative acknowledge models.CFDP is designed to provide data and storage management,story and forward,custody transfer and reliable end-to-end delivery over deep space characterized by huge latency,intermittent link,asymmetric bandwidth and big bit error rate（BER）.Four reliable transmission models are analyzed and an expected file-delivery time is calculated with different trans-mission rates,numbers and sizes of packet data units,BERs and frequencies of external events,etc.By comparison of four CFDP models,the requirement of BER for typical missions in deep space is obtained and rules of choosing CFDP models under different uplink state informations are given,which provides references for protocol models selection,utilization and modification.展开更多
Objective： To review the current situation and progress of traditional Chinese medicine（TCM） international standards, standard projects and proposals in International Organization for Standardization（ISO）/technic...Objective： To review the current situation and progress of traditional Chinese medicine（TCM） international standards, standard projects and proposals in International Organization for Standardization（ISO）/technical committee（TC） 249. Methods： ISO/TC 249 standards and standard projects on the ISO website were searched and new standard proposals information were collected from ISO/TC 249 National Mirror Committee in China. Then all the available data were summarized in 5 closely related items, including proposed time, proposed country, assigned working group（WG）, current stage and classification. Results： In ISO/TC 249, there were 2 international standards, 18 standard projects and 24 new standard proposals proposed in 2014. These 44 standard subjects increased year by year since 2011. Twenty-nine of them were proposed by China, 15 were assigned to WG 4, 36 were in preliminary and preparatory stage and 8 were categorized into 4 fields, 7 groups and sub-groups based on International Classification Standards. Conclusion： A rapid and steady development of international standardization in TCM can be observed in ISO/TC 249.展开更多
Tourism industry has become an important part of Indian economy,and tourism development has been,however,concentrated to a few areas. Accumulation of tourism activities has reached the critical stage in most of the to...Tourism industry has become an important part of Indian economy,and tourism development has been,however,concentrated to a few areas. Accumulation of tourism activities has reached the critical stage in most of the tourism centers,which pose serious threats to the natural environment. The Bhyundar Valley of Nanda Devi Biosphere Reserve (NDBR) in Uttarakhand State of the Indian Himalaya is a burning example of such problems. Land use/cover changes,deforestation and accumulation of garbage are some of the negative impacts of unregulated tourism in the valley. Unsustainable activities of tourists and villagers in the valley make such problems very severe. To deal with the ongoing problems and ensure community involvement in tourism management and environmental conservation,the Biosphere Reserve Authority introduced ecotourism in the form of Eco Development Committees (EDCs) in the Bhyundar Valley. Study reveals that many problems associated with tourism have been minimized to some extent with the help of EDCs but few are still prevailing in valley. However,the existing attempts to conserve the valley from the negative effects of tourism are inadequate and modifications are needed in the current initiatives.展开更多
The annex A of the United Nations Scientific Committee on the Effects of Atomic Radiation(UNSCEAR)2020/2021 Report presented a comprehensive global estimate of frequencies and doses from medical exposure to ionizing r...The annex A of the United Nations Scientific Committee on the Effects of Atomic Radiation(UNSCEAR)2020/2021 Report presented a comprehensive global estimate of frequencies and doses from medical exposure to ionizing radiation,their distribution and trends for the period 2009-2018.The annex considered four general categories of medical practice using ionizing radiation:(a)diagnostic radiology,including dental radiology and computed tomography,(b)interventional radiology(image-guided interventional procedures),(c)nuclear medicine,and(d)radiation therapy.In the period 2009-2018,about 4.2 billion medical radiological examinations were performed annually,resulting in an annual effective dose of 0.57 mSv per caput.The use of computed tomography has continued to grow and the contribution from interventional radiology has increased rapidly in recent years.The annual number of radionuclide therapy treatments has increased by 60% since the UNSCEAR 2008 Report,while the number of courses of radiation therapy has increased by 22%.Medical exposure remains by far the largest human-made source of radiation exposure to the public.The Committee's evaluation relies on the collection of up-to-date and representative exposure data from all Member States of the United Nations.Future exposure survey should be more relevant and useful and adapted to changing data sources and changing uses of radiation across the world.展开更多
The annex D of the United Nations Scientific Committee on the Effects of Atomic Radiation(UNSCEAR)2020/2021 Report presented a comprehensive global estimate of occupational exposure to ionizing radiation.The worldwide...The annex D of the United Nations Scientific Committee on the Effects of Atomic Radiation(UNSCEAR)2020/2021 Report presented a comprehensive global estimate of occupational exposure to ionizing radiation.The worldwide annual number of workers exposed to natural and human-made sources of ionizing radiation was estimated to be approximately 24 million in the period 2010-2014.About 52% of those were employed in the sectors that involve exposure to natural sources of radiation.The worldwide average annual effective dose for all workers during the period 2010-2014 was estimated to be around 1.2 mSv-about two thirds of the value estimated for the period 1995-1999.The annual effective dose was estimated to be around 2.0 mSv for workers exposed to natural sources and 0.5 mSv for workers exposed to human-made sources.The overriding limitation of current evaluation was the low rate of participation by United Nations Member States in providing occupational exposure monitoring data,especially data from non-nuclear sectors and occupational sectors involving naturally occurring radioactive materials.As the assessment of the worldwide occupational exposure is a complex task,the Committee relies on the collection of up-to-date data on occupational exposure from United Nations Member States in a broad range of occupational sectors,and continues collaboration with international organizations.展开更多
文摘This paper highlights the role of automation technologies for improving the safety, productivity, and environmental sustainability of underground coal mining processes. This is accomplished by reviewing the impact that the introduction of automation technology has made through the longwall shearer automation research program of Longwall Automation Steering Committee(LASC). This result has been achieved through close integration of sensing, processing, and control technologies into the longwall mining process. Key to the success of the automation solution has been the development of new sensing methods to accurately measure the location of longwall equipment and the spatial configuration of coal seam geology. The relevance of system interoperability and open communications standards for facilitating effective automation is also discussed. Importantly, the insights gained through the longwall automation development process are now leading to new technology transfer activity to benefit other underground mining processes.
基金Supported by the National High Technology Research and Development Program of China (2006AA040309)National BasicResearch Program of China (2007CB714000)
文摘Presented is a multiple model soft sensing method based on Affinity Propagation （AP）, Gaussian process （GP） and Bayesian committee machine （BCM）. AP clustering arithmetic is used to cluster training samples according to their operating points. Then, the sub-models are estimated by Gaussian Process Regression （GPR）. Finally, in order to get a global probabilistic prediction, Bayesian committee mactnne is used to combine the outputs of the sub-estimators. The proposed method has been applied to predict the light naphtha end point in hydrocracker fractionators. Practical applications indicate that it is useful for the online prediction of quality monitoring in chemical processes.
文摘The International Committee of Medical Journal Editors （ICMJE） believes that there is an ethical obligation to responsibly share data generated by interventional clinical trials because participants have put themselves at risk. In a growing consensus, many funders around the world - foundations, government agencies, and industry - now mandate data sharing. Here, we outline ICMJE＇s proposed requirements to help meet this obligation. We encourage feedback on the proposed requirements. Anyone can provide feedback at www. icmje.org by April 18, 2016.
基金This work was supported by the National Natural Science Foundation of China(No.81602143)National 135 Major Project of China(2018ZX10723204+1 种基金2018ZX10302205)Sun Yat-sen University Cancer Center physician scientist funding(No.16zxqk04)
文摘Background:Patients with hepatocellular carcinoma(HCC)undergoing surgical resection still have a high 5-year recurrence rate(~60%).With the development of laparoscopic hepatectomy(LH),few studies have compared the efficacy between LH and traditional surgical approach on HCC.The objective of this study was to establish a nomo-gram to evaluate the risk of recurrence in HCC patients who underwent LH.Methods:The clinical data of 432 patients,pathologically diagnosed with HCC,underwent LH as initial treatment and had surgical margin>1 cm were collected.The significance of their clinicopathological features to recurrence-free survival(RFS)was assessed,based on which a nomogram was constructed using a training cohort(n=324)and was internally validated using a temporal validation cohort(n=108).Results:Hepatitis B surface antigen(hazard ratio[HR],1.838;P=0.044),tumor number(HR,1.774;P=0.003),tumor thrombus(HR,2.356;P=0.003),cancer cell differentiation(HR,0.745;P=0.080),and microvascular tumor invasion(HR,1.673;P=0.007)were found to be independent risk factors for RFS in the training cohort,and were used for con-structing the nomogram.The C-index for RFS prediction in the training cohort using the nomogram was 0.786,which was higher than that of the 8th edition of the American Joint Committee on Cancer TNM classification(C-index,0.698)and the Barcelona Clinic Liver Cancer staging system(C-index,0.632).A high consistency between the nomogram prediction and actual observation was also demonstrated by a calibration curve.An improved predictive benefit in RFS and higher threshold probability of the nomogram were determined by receiver operating characteristic curve analysis,which was also confirmed in the validation cohort compared to other systems.Conclusions:We constructed and validated a nomogram able to quantify the risk of recurrence after initial LH for HCC patients,which can be clinically implemented in assisting the planification of individual postoperative surveil-lance protocols.
文摘当前数字电视发展速度很快,在个别地方甚至已经开始逐步普及,但是由于经济,技术等原因,在电视广播领域,模拟电视广播还将在很长一段时间内占据主导地位.在不改变现有模拟电视广播系统的条件下,如何有效的提高视频图像的质量已经成为一个热门的话题.将数字解码技术用在改善传统的模拟电视广播质量上,用数字方法提高模拟视频的图像质量,和传统的模拟视频解码相比,解码性能较高,并且为后端数字视频处理提供优质视频源.对于模拟视频信号的解码系统,亮色分离和色度解调是视频解码的两个关键点.对于NTSC(national television system committee)制式的视频解码,当前已有的几种优质的解码算法中,亮色分离均用3D自适应梳状滤波,色度解调采用数字锁相环,均能实现优质的视频解码效果,但其共同点为算法复杂,硬件实现难度大,成本高.本文在深入研究NTSC制式编解码的基础上提出一种精简高效的数字解码方法,将传统的NTSC制式彩色全电视信号,通过高速高分辨率的FPGA(field programmable gate array)硬件采集系统转化为数字视频流,提出一种改进型自适应2D梳状滤波器进行亮色分离,相比3D梳状滤波器,在满足视频解码质量需要的基础上大幅度简化了算法,利用相位估计法恢复色同步副载波,相比数字锁相环,除简化了算法外,还避免了数字锁相环偶尔失锁的可能,且对前端视频数字化采集的采样率无特殊要求.解码后的视频分量信号可在数字视频设备上直接显示,并可为后端的数字视频图像处理等提供优质的数字视频信号源.该解码算法在MATLAB上模拟,具有解码后的图像质量良好,运算速度快和解码系统精简等特点.
基金Supported by Department of Biochemistry,Institute of Medicine.Tribhuvan University Teaching Hospital,Kathmandu.Nepal(Grant No.30-956/2013CEA)
文摘Objective:To develop the missing link between hyperuricemia and hypertension.Methods:The study was conducted in Department of Biochemistry in collaboration with Nephrology Unit of Internal Medicine Department.Hypertension was defined according to blood pressure readings by definitions of the Seventh Report of the Joint National Committee.Totally 205newly diagnosed and untreated essential hypertensive cases and age-sex matched nonnotensive controls were enrolled in the study.The potential confounding factors of hyperuricemia and hypertension in both cases and controls were controlled.Uric acid levels in all participants were analyzed.Results:Renal function between newly diagnosed hypertensive cases and nonnotensive healthy controls were adjusted.The mean serum uric acid observed in newly diagnosed hypertensive cases and in nonnotensive healthy controls were(290.05±87.03)μmol/L and(245.24±09.38)μmol/L respectively.A total of 59(28.8%)participants of cases and 28(13.7%)participants of controls had hyperuricemia(odds ratio 2.555(95%CI:1.549-4.213),P<0.00l).Conclusions:The mean serum uric acid leveb and number of hyperuricemic subjects were found to be significantly higher in cases when compared to controls.
文摘2017年,美国癌症联合会（American joint committee on cancer,AJCC）对甲状腺癌的TNM临床分期进行了调整,降低了17%的低危患者的临床分期,这部分患者多具有年轻化的特点,因此美容需求高。全腔镜甲状腺癌功能性颈淋巴结清扫具有较好的美容效果,对患者心理的创伤较小;针式辅助技术可降低手术难度。在腔镜甲状腺手术中,
文摘Background： Current understanding of tumor biology suggests that breast cancer is a group of diseases with different intrinsic molecular subtypes. Anatomic staging system alone is insufficient to provide future outcome information. The American Joint Committee on Cancer （AJCC） expert panel updated the 8th edition of the staging manual with prognostic stage groups by incorporating biomarkers into the anatomic stage groups. In this study, we retrospectively analyzed the data from our center in China using the anatomic and prognostic staging system based on the AJCC 8th edition staging manual. Methods： We reviewed the data from January 2008 to December 2014 for cases with Luminal B Human Epidermal Growth Factor Receptor 2 （HER2）-negative breast cancer in our center. All cases were restaged using the AJCC 8th edition anatomic and prognostic staging system. The Kaplan-Meier method and log-rank test were used to compare the survival differences between different subgroups. SPSS software version 19.0 （IBM Corp., Armonk, NY, USA） was used for the statistical analyses. Results： This study consisted of 796 patients with Luminal B HER-negative breast cancer. The 5-year disease-free survival （DFS） of 769 Stage I-III patients was 89.7%, and the 5-year overall survival （OS） of all 796 patients was 91.7%. Both 5-year DFS and 5-year OS were significantly different in the different anatomic and prognostic stage groups, There were 372 cases （46.7%） assigned to a different group. The prognostic Stage II and III patients restaged from anatomic Stage III had significant differences in 5-year DFS （v2 = 11.319; P = 0.001） and 5-year OS （χ2 = 5.225, P = 0.022）. In addition, cases restaged as prognostic Stage I, II, or III from the anatomic Stage II group had statistically significant differences in 5-year DFS （χ2 = 6.510, P = 0.039） but no significant differences in 5-year OS （χ2 = 5.087, P = 0.079）. However, the restaged prognostic Stage I and II cases from anatomic Stage I had no statis
基金supported by the National Natural Science Fandation of China (6067208960772075)
文摘In consultative committee for space data systems（CCSDS） file delivery protocol（CFDP） recommendation of reliable transmission,there are no detail transmission procedure and delay calculation of prompted negative acknowledge and asynchronous negative acknowledge models.CFDP is designed to provide data and storage management,story and forward,custody transfer and reliable end-to-end delivery over deep space characterized by huge latency,intermittent link,asymmetric bandwidth and big bit error rate（BER）.Four reliable transmission models are analyzed and an expected file-delivery time is calculated with different trans-mission rates,numbers and sizes of packet data units,BERs and frequencies of external events,etc.By comparison of four CFDP models,the requirement of BER for typical missions in deep space is obtained and rules of choosing CFDP models under different uplink state informations are given,which provides references for protocol models selection,utilization and modification.
基金Supported by the State Administration of Traditional Chinese medicine of China(No.ZZYZK2013-Guohesi A)China Academy of Chinese Medical Sciences(No.Z0243,No.Z0411)
文摘Objective： To review the current situation and progress of traditional Chinese medicine（TCM） international standards, standard projects and proposals in International Organization for Standardization（ISO）/technical committee（TC） 249. Methods： ISO/TC 249 standards and standard projects on the ISO website were searched and new standard proposals information were collected from ISO/TC 249 National Mirror Committee in China. Then all the available data were summarized in 5 closely related items, including proposed time, proposed country, assigned working group（WG）, current stage and classification. Results： In ISO/TC 249, there were 2 international standards, 18 standard projects and 24 new standard proposals proposed in 2014. These 44 standard subjects increased year by year since 2011. Twenty-nine of them were proposed by China, 15 were assigned to WG 4, 36 were in preliminary and preparatory stage and 8 were categorized into 4 fields, 7 groups and sub-groups based on International Classification Standards. Conclusion： A rapid and steady development of international standardization in TCM can be observed in ISO/TC 249.
文摘Tourism industry has become an important part of Indian economy,and tourism development has been,however,concentrated to a few areas. Accumulation of tourism activities has reached the critical stage in most of the tourism centers,which pose serious threats to the natural environment. The Bhyundar Valley of Nanda Devi Biosphere Reserve (NDBR) in Uttarakhand State of the Indian Himalaya is a burning example of such problems. Land use/cover changes,deforestation and accumulation of garbage are some of the negative impacts of unregulated tourism in the valley. Unsustainable activities of tourists and villagers in the valley make such problems very severe. To deal with the ongoing problems and ensure community involvement in tourism management and environmental conservation,the Biosphere Reserve Authority introduced ecotourism in the form of Eco Development Committees (EDCs) in the Bhyundar Valley. Study reveals that many problems associated with tourism have been minimized to some extent with the help of EDCs but few are still prevailing in valley. However,the existing attempts to conserve the valley from the negative effects of tourism are inadequate and modifications are needed in the current initiatives.
文摘The annex A of the United Nations Scientific Committee on the Effects of Atomic Radiation(UNSCEAR)2020/2021 Report presented a comprehensive global estimate of frequencies and doses from medical exposure to ionizing radiation,their distribution and trends for the period 2009-2018.The annex considered four general categories of medical practice using ionizing radiation:(a)diagnostic radiology,including dental radiology and computed tomography,(b)interventional radiology(image-guided interventional procedures),(c)nuclear medicine,and(d)radiation therapy.In the period 2009-2018,about 4.2 billion medical radiological examinations were performed annually,resulting in an annual effective dose of 0.57 mSv per caput.The use of computed tomography has continued to grow and the contribution from interventional radiology has increased rapidly in recent years.The annual number of radionuclide therapy treatments has increased by 60% since the UNSCEAR 2008 Report,while the number of courses of radiation therapy has increased by 22%.Medical exposure remains by far the largest human-made source of radiation exposure to the public.The Committee's evaluation relies on the collection of up-to-date and representative exposure data from all Member States of the United Nations.Future exposure survey should be more relevant and useful and adapted to changing data sources and changing uses of radiation across the world.
文摘The annex D of the United Nations Scientific Committee on the Effects of Atomic Radiation(UNSCEAR)2020/2021 Report presented a comprehensive global estimate of occupational exposure to ionizing radiation.The worldwide annual number of workers exposed to natural and human-made sources of ionizing radiation was estimated to be approximately 24 million in the period 2010-2014.About 52% of those were employed in the sectors that involve exposure to natural sources of radiation.The worldwide average annual effective dose for all workers during the period 2010-2014 was estimated to be around 1.2 mSv-about two thirds of the value estimated for the period 1995-1999.The annual effective dose was estimated to be around 2.0 mSv for workers exposed to natural sources and 0.5 mSv for workers exposed to human-made sources.The overriding limitation of current evaluation was the low rate of participation by United Nations Member States in providing occupational exposure monitoring data,especially data from non-nuclear sectors and occupational sectors involving naturally occurring radioactive materials.As the assessment of the worldwide occupational exposure is a complex task,the Committee relies on the collection of up-to-date data on occupational exposure from United Nations Member States in a broad range of occupational sectors,and continues collaboration with international organizations.
