This paper primarily concerns the effective coordination of the procedures and methods employed in open pit mining operations under the background of river management.The central objective of this study is to identify...This paper primarily concerns the effective coordination of the procedures and methods employed in open pit mining operations under the background of river management.The central objective of this study is to identify a viable approach for ensuring rational and efficient development of open pit mineral resources while simultaneously protecting and restoring the ecological environment of the river.This approach should facilitate the realization of a harmonious symbiosis between mining and river management.The intricate mutual influence relationship between river management and open pit mining is first analyzed in depth,which provides a solid foundation for the subsequent coordination strategy development.In light of the aforementioned considerations,a set of coordination procedures for open pit mining based on river management conditions is proposed.These procedures emphasize the integration of river protection into the overall layout of mining at the planning stage.The implementation of scientific mining schemes,accompanied by rigorous control of the scope and depth of mining operations,has proven to be an effective means of reducing the impact of mining activities on river environments.This approach has also facilitated the achievement of a balance and coordination between mining and river management.展开更多
his paper examines planning management problems in a Multiagentbased Distributed Open Computing Environment Model (MDOCEM). First the meaning of planning management in MDOCEM is introduced, and then a formal method to...his paper examines planning management problems in a Multiagentbased Distributed Open Computing Environment Model (MDOCEM). First the meaning of planning management in MDOCEM is introduced, and then a formal method to describe the associated task partition problems is presented, and a heuristic algorithm which gives an approximate optimum solution is given. Finally the task coordination and integration of execution results are discussed.展开更多
In order to manage all kinds of network security devices and software systems efficiently, and make them collaborate with each other, the model for an open network security management platform is presented. The feasib...In order to manage all kinds of network security devices and software systems efficiently, and make them collaborate with each other, the model for an open network security management platform is presented. The feasibility and key implementing technology of the model are expatiated. A prototype system is implemented to validate it.展开更多
There are a number of geotechnical systems used at open cut operations of Anglo American's Metallurgical Coal business unit in Australia. These systems are mainly mine site specific, based on geological informatio...There are a number of geotechnical systems used at open cut operations of Anglo American's Metallurgical Coal business unit in Australia. These systems are mainly mine site specific, based on geological information and used as hazard plans. They are qualitative and reliant upon the experienced judgement of site based engineers and the general workforce. They are not suitable for calculating the associated risks of geological structures and mining responses. A uniform risk rating system that can be used to provide an unbiased, standard and quantifiable assessment of the risk from highwall and lowwall failures is therefore developed using the experience gained with such systems in Anglo American's South African operations. This system is a semi-quantitative risk rating system and takes into account the relative differences in the importance of hazards as experienced at each mine site as a result of different combinations of geotechnical factors and mining conditions. It is based on critical geotechnical and other parameters that have been identified by site mining engineers, geologists and geotechnical engineers. The primary advantage of this risk rating system is that all open cut mines in the Anglo American's Metallurgical Coal operations use a near identical system, which enables the user to compare the risk after each blast and with other mines. The system can be adjusted to meet local mine specific requirements. The implementation of this system, a computer program that automatically calculates the risks and recommends predetermined controls, has been made as practical and as easy to use as possible. This program can be used by personnel from other mining disciplines not directly related to geotechnical engineering.展开更多
The Shanghai Cooperation Organization (SCO) Management System Certification Research Class formally opened in Beijing on September 6, 2007. The research class was attended by government officials and experts in th... The Shanghai Cooperation Organization (SCO) Management System Certification Research Class formally opened in Beijing on September 6, 2007. The research class was attended by government officials and experts in the fields of industry, commerce,environmental protection,statistics, standardization,metrology, detection and certification from Kazakhstan, Kyrgyzstan, Uzbekistan and Tajikistan.……展开更多
Objectives: To evaluate therapeutic and prognosis of Uretero-pelvic junction abnomalities. Methods: This article was retrospective and descriptive, covering a period of six months, running from January 1st to December...Objectives: To evaluate therapeutic and prognosis of Uretero-pelvic junction abnomalities. Methods: This article was retrospective and descriptive, covering a period of six months, running from January 1st to December 31st, 2013 and conducted?to evaluate therapeutic and prognosis of Uretero-pelvic junction abnormalities. Included criteria were all patients whose diagnosis was abnormalities of the uretero-pelvic junction and had been confirmed after para clinical explorations. The stricture of the junction after a first kidney surgery did not include. The Creatinine level has considered high from 15 mg/l. Results: The median age was 35 years old. Age groups (30 - 40) years old have predominated in 36.2%. A male predominance had been noted in 62.3% versus 37.7% women. The most affected occupation was the officials in 37.7% of cases. The main reason for consultation was lumbar pain in 97.1%. The high creatinine level has observed in 19 patients (27.5%). Sixty-one patients (88.41%) have been operated. An abstention has been observed in 7 patients (10.14%) and one patient died before the surgical issue in renal failure. The early post-operative course has been uneventful in 78.7% (48 cases) and complicated in 21.3% (21 cases). Conclusions: Open surgery tends to disappear at the expense of the endopyelotomy and laparoscopy which gives best results. However, it is still relevant.展开更多
Based on open grid service architecture (OGSA) and Globus Toolkit 3. 0 (GT3), a manufacturing grid (MG) is proposed to realize resource sharing and collaborative working among manufacturing enterprises. Nevertheless, ...Based on open grid service architecture (OGSA) and Globus Toolkit 3. 0 (GT3), a manufacturing grid (MG) is proposed to realize resource sharing and collaborative working among manufacturing enterprises. Nevertheless, resource management in MG is much more complicated than that in other grid applications due to the geographically distributed manufacturing resources, which range from CAD, CAPP and CAE to various kinds of machine tools. With the interaction of manufacturing grid information service (MGIS, developed by ourselves) and globus resource allocation manager (GRAM, provided by GT3), a resource management framework is presented to perform the functions of resource encapsulation, registry, discovery and monitoring. Furthermore, the application architecture and an example are depicted to illustrate the utilization of the resource management system.展开更多
Acute pancreatitis(AP)is a serious condition presenting catastrophic consequences.In severe AP,the mortality rate is high,and some patients initially diagnosed with mild-to-moderate AP can progress to a life-threateni...Acute pancreatitis(AP)is a serious condition presenting catastrophic consequences.In severe AP,the mortality rate is high,and some patients initially diagnosed with mild-to-moderate AP can progress to a life-threatening severe state.Treatment of AP has evolved over the years.Drainage was the first surgical procedure performed for AP;however,later,surgical approaches were replaced by more conservative approaches due to the availability of advanced medical care and improved understanding of the course of AP.Currently,surgery is used to manage several complications of AP,such as pseudocysts,pancreatic fistulas,and biliary tract obstruction.Patients who are unresponsive to conservative treatment or have complications are typically considered for surgical intervention.This review focuses on the surgical approaches(endoscopic,percutaneous,and open)that have been established in recent studies to treat this acute condition and summarizes the common management guidelines for AP,discussing the relevant indications,significance,and complications.It is evident that despite their reduced involvement,surgeons lead the multidisciplinary care of patients with AP;however,given the gaps in existing knowledge,more research is required to standardize surgical protocols for AP.展开更多
Traditional SNMP-based network management can not deal with the task of managing large-scaled distributed network,while policy-based management is one of the effective solutions in network and distributed systems mana...Traditional SNMP-based network management can not deal with the task of managing large-scaled distributed network,while policy-based management is one of the effective solutions in network and distributed systems management.However,cross-vendor hardware compatibility is one of the limitations in policy-based management.Devices existing in current network mostly support SNMP rather than Common Open Policy Service(COPS)protocol.By analyzing traditional network management and policy-based network management,a scalable network management framework is proposed.It is combined with Internet Engineering Task Force(IETF)framework for policy-based management and SNMP-based network management.By interpreting and translating policy decision to SNMP message,policy can be executed in traditional SNMP-based device.展开更多
Steel 20Mn23AlV is a type of high aluminum steel with a very low ladle free-opening rate. The aluminum composition of 20Mn23AlV ranges from 1.6% to 2.45% ,which is significantly higher than other types of steel. Accor...Steel 20Mn23AlV is a type of high aluminum steel with a very low ladle free-opening rate. The aluminum composition of 20Mn23AlV ranges from 1.6% to 2.45% ,which is significantly higher than other types of steel. According to the real condition of 40 t ladle in steel-making plant of Baosteel Special Steel Company, previous works show that the key factors affecting the ladle free-opening rate of high aluminum steel in continuous casting are:sand material, accessories baking, ladle nozzle cleaning, the process and amount of adding sand, and the rate of argon stirring during refining. Therefore, improving the ladle filler sand quality, baking all of the raw materials, controlling the addition of ladle filler sand, cleaning the ladle nozzle, and optimizing argon stirring during the refining process can resolve the problem of a low ladle free-opening rate of high aluminum steel caused by the long ladle time of liquid steel.展开更多
A brief outline of Energy Management System (EMS) in China is given and OPEN-2000 EMS, combined with the novel technique of computer science, is introduced. The system has been developed by Power System Control Divisi...A brief outline of Energy Management System (EMS) in China is given and OPEN-2000 EMS, combined with the novel technique of computer science, is introduced. The system has been developed by Power System Control Division of NARI and put into operation in the middle of 1998.展开更多
The authors designed an ecological storm water system in a residential area to replace the conventional underground channels for the collection of storm water so as to reduce the nutrients and sediments discharged. Th...The authors designed an ecological storm water system in a residential area to replace the conventional underground channels for the collection of storm water so as to reduce the nutrients and sediments discharged. This system contains natural sub-creeks as drainage channels discharging overflow to nearby creeks, an open green trench, a storage pond, and natural sub-creeks. The sub -creeks were designed to be integrated into community landscape, which not only increases the efficiency of water usage, but also improves the aesthetic qualities of the community residence area as required by Agenda 21. This research proved the feasibility of an open storm water collection and utilization system for the design of a community water system.展开更多
The Xuyi Schmidt Telescope Photometric Survey of the Galactic Anti-center(XSTPS-GAC)is a photometric sky survey that covers nearly 6000 deg^2 towards the Galactic Anti-center(GAC) in the g,r,i bands. Half of its s...The Xuyi Schmidt Telescope Photometric Survey of the Galactic Anti-center(XSTPS-GAC)is a photometric sky survey that covers nearly 6000 deg^2 towards the Galactic Anti-center(GAC) in the g,r,i bands. Half of its survey field is located on the Galactic Anti-center disk,which makes XSTPSGAC highly suitable to search for new open clusters in the GAC region. In this paper,we report new open cluster candidates discovered in this survey,as well as properties of these open cluster candidates,such as age,distance and reddening,derived by isochrone fitting in the color-magnitude diagram(CMD).These open cluster candidates are stellar density peaks detected in the star density maps by applying the method from Koposov et al. Each candidate is inspected in terms of its true color image composed from three XSTPS-GAC band images. Then its CMD is checked,in order to identify whether the central region stars have a clear isochrone-like trend differing from background stars. The parameters derived from isochrone fitting for these candidates are mainly based on three band photometry of XSTPS-GAC.Moreover,when these new candidates are able to be seen clearly in 2 MASS data,their parameters are also derived based on the 2 MASS(J-H,J) CMD. There are a total of 320 known open clusters rediscovered and 24 new open cluster candidates discovered in this work. Furthermore,the parameters of these new candidates,as well as another 11 previously known open clusters,are properly determined for the first time.展开更多
It has been found that there are marked errors in the value of valid opening size of heat-bonded nonwoven fabrics between theoretical calculations and engineering measurements. A new modified theoretical model is adva...It has been found that there are marked errors in the value of valid opening size of heat-bonded nonwoven fabrics between theoretical calculations and engineering measurements. A new modified theoretical model is advanced in this paper. The equivalent diameter of the pore of a fibre web is used to calculate the valid opening size instead of the maximum diameter of inscribed circle used, because the fibres in practical fibre webs are flexible elastomers with definite diameters and the pore of fibre web may produce deformation in screening teat and engineering usage. The results show that the theoretical calculations coincide well with the engineering measurements. This method offers a theoretical basis for computer simulation to the performance of filters of heatbonded nonwoven fabrics.展开更多
This paper presents a preliminary test of the k-th nearest neighbor distance (KNND) method for detecting nearby open clusters based on Gaia-DR1. We select 38 386 nearby stars (〈 100 pc) from the Gaia-DR1 catalog,...This paper presents a preliminary test of the k-th nearest neighbor distance (KNND) method for detecting nearby open clusters based on Gaia-DR1. We select 38 386 nearby stars (〈 100 pc) from the Gaia-DR1 catalog, and then use the KNND method to detect overdense regions in three-dimensional space. We find two overdense regions (the Hyades and Coma Berenices (Coma Ber) open clusters), and obtain 57 reliable cluster members. Based on these cluster members, the distances to the Hyades and Coma Ber clusters are determined to be 46.0±0.2 and 83.5±0.3 pc, respectively. Our results demonstrate that the KNND method can be used to detect open clusters based on a large volume of astrometry data.展开更多
<strong>Purpose of Review:</strong> The management of eye injuries is both difficult and argumentative. This study attempts to highlight the management of ocular trauma using currently available informatio...<strong>Purpose of Review:</strong> The management of eye injuries is both difficult and argumentative. This study attempts to highlight the management of ocular trauma using currently available information in the literature and author experience. This review presents a workable framework from the first presentation, epidemiology, classification, investigations, management principles, complications, prognostic factors, final visual outcome and management debates. <strong>Review Findings:</strong> Mechanical ocular trauma is a leading cause of monocular blindness and possible handicap worldwide. Among several classification systems, the most widely accepted is Birmingham Eye Trauma Terminology (BETT). Mechanical ocular trauma is a topic of unsolved controversy. Patching for corneal abrasion, paracentesis for hyphema, the timing of cataract surgery and intraocular lens implantation are all issues in anterior segment injuries. Regarding posterior segment controversies, the timing of vitrectomy, use of prophylactic cryotherapy, the necessity of intravitreal antibiotics in the absence of infection, the use of vitrectomy vs vitreous tap in traumatic endophthalmitis is the issues. The pediatric age group needs to be approached by a different protocol due to the risk of amblyopia, intraocular inflammation, and significant vitreoretinal adhesions. The various prognostic factors have a role in the final visual outcome. B scan is used to exclude R.D, Intraocular foreign body (IOFB), and vitreous haemorrhage in hazy media. Individual surgical strategies are used for every patient according to the classification and extent of the injuries. <strong>Conclusion:</strong> This article examines relevant evidence on the management challenges and controversies of mechanical trauma of the eye and offers treatment recommendations based on published research and the authors’ own experience.展开更多
BACKGROUND Bile leakage is a common and serious complication of open hepatectomy for the treatment of biliary tract cancer.AIM To evaluate the incidence,risk factors,and management of bile leakage after open hepatecto...BACKGROUND Bile leakage is a common and serious complication of open hepatectomy for the treatment of biliary tract cancer.AIM To evaluate the incidence,risk factors,and management of bile leakage after open hepatectomy in patients with biliary tract cancer.METHODS We retrospectively analyzed 120 patients who underwent open hepatectomy for biliary tract cancer from February 2018 to February 2023.Bile leak was defined as bile drainage from the surgical site or drain or the presence of a biloma on imaging.The incidence,severity,timing,location,and treatment of the bile leaks were recorded.The risk factors for bile leakage were analyzed using univariate and multivariate logistic regression analyses.RESULTS The incidence of bile leak was 16.7%(20/120),and most cases were grade A(75%,15/20)according to the International Study Group of Liver Surgery classification.The median time of onset was 5 d(range,1-14 d),and the median duration was 7 d(range,2-28 d).The most common location of bile leakage was the cut surface of the liver(70%,14/20),followed by the anastomosis site(25%,5/20)and the cystic duct stump(5%,1/20).Most bile leaks were treated conservatively with drainage,antibiotics,and nutritional support(85%,17/20),whereas some required endoscopic retrograde cholangiopancreatography with stenting(10%,2/20)or percutaneous transhepatic cholangiography with drainage(5%,1/20).Risk factors for bile leakage include male sex,hepatocellular carcinoma,major hepatectomy,blood loss,and blood transfusion.CONCLUSION Bile leakage is a frequent complication of open hepatectomy for biliary tract cancer.However,most cases are mild and can be conservatively managed.Male sex,hepatocellular carcinoma,major hepatectomy,blood loss,and blood transfusion were associated with an increased risk of bile leak.展开更多
文摘This paper primarily concerns the effective coordination of the procedures and methods employed in open pit mining operations under the background of river management.The central objective of this study is to identify a viable approach for ensuring rational and efficient development of open pit mineral resources while simultaneously protecting and restoring the ecological environment of the river.This approach should facilitate the realization of a harmonious symbiosis between mining and river management.The intricate mutual influence relationship between river management and open pit mining is first analyzed in depth,which provides a solid foundation for the subsequent coordination strategy development.In light of the aforementioned considerations,a set of coordination procedures for open pit mining based on river management conditions is proposed.These procedures emphasize the integration of river protection into the overall layout of mining at the planning stage.The implementation of scientific mining schemes,accompanied by rigorous control of the scope and depth of mining operations,has proven to be an effective means of reducing the impact of mining activities on river environments.This approach has also facilitated the achievement of a balance and coordination between mining and river management.
文摘his paper examines planning management problems in a Multiagentbased Distributed Open Computing Environment Model (MDOCEM). First the meaning of planning management in MDOCEM is introduced, and then a formal method to describe the associated task partition problems is presented, and a heuristic algorithm which gives an approximate optimum solution is given. Finally the task coordination and integration of execution results are discussed.
文摘In order to manage all kinds of network security devices and software systems efficiently, and make them collaborate with each other, the model for an open network security management platform is presented. The feasibility and key implementing technology of the model are expatiated. A prototype system is implemented to validate it.
文摘There are a number of geotechnical systems used at open cut operations of Anglo American's Metallurgical Coal business unit in Australia. These systems are mainly mine site specific, based on geological information and used as hazard plans. They are qualitative and reliant upon the experienced judgement of site based engineers and the general workforce. They are not suitable for calculating the associated risks of geological structures and mining responses. A uniform risk rating system that can be used to provide an unbiased, standard and quantifiable assessment of the risk from highwall and lowwall failures is therefore developed using the experience gained with such systems in Anglo American's South African operations. This system is a semi-quantitative risk rating system and takes into account the relative differences in the importance of hazards as experienced at each mine site as a result of different combinations of geotechnical factors and mining conditions. It is based on critical geotechnical and other parameters that have been identified by site mining engineers, geologists and geotechnical engineers. The primary advantage of this risk rating system is that all open cut mines in the Anglo American's Metallurgical Coal operations use a near identical system, which enables the user to compare the risk after each blast and with other mines. The system can be adjusted to meet local mine specific requirements. The implementation of this system, a computer program that automatically calculates the risks and recommends predetermined controls, has been made as practical and as easy to use as possible. This program can be used by personnel from other mining disciplines not directly related to geotechnical engineering.
文摘 The Shanghai Cooperation Organization (SCO) Management System Certification Research Class formally opened in Beijing on September 6, 2007. The research class was attended by government officials and experts in the fields of industry, commerce,environmental protection,statistics, standardization,metrology, detection and certification from Kazakhstan, Kyrgyzstan, Uzbekistan and Tajikistan.……
文摘Objectives: To evaluate therapeutic and prognosis of Uretero-pelvic junction abnomalities. Methods: This article was retrospective and descriptive, covering a period of six months, running from January 1st to December 31st, 2013 and conducted?to evaluate therapeutic and prognosis of Uretero-pelvic junction abnormalities. Included criteria were all patients whose diagnosis was abnormalities of the uretero-pelvic junction and had been confirmed after para clinical explorations. The stricture of the junction after a first kidney surgery did not include. The Creatinine level has considered high from 15 mg/l. Results: The median age was 35 years old. Age groups (30 - 40) years old have predominated in 36.2%. A male predominance had been noted in 62.3% versus 37.7% women. The most affected occupation was the officials in 37.7% of cases. The main reason for consultation was lumbar pain in 97.1%. The high creatinine level has observed in 19 patients (27.5%). Sixty-one patients (88.41%) have been operated. An abstention has been observed in 7 patients (10.14%) and one patient died before the surgical issue in renal failure. The early post-operative course has been uneventful in 78.7% (48 cases) and complicated in 21.3% (21 cases). Conclusions: Open surgery tends to disappear at the expense of the endopyelotomy and laparoscopy which gives best results. However, it is still relevant.
基金TheDevelopingFoundationofShanghaiScienceandTechnologyCommittee (No .0 2 5 1110 5 5 ) .
文摘Based on open grid service architecture (OGSA) and Globus Toolkit 3. 0 (GT3), a manufacturing grid (MG) is proposed to realize resource sharing and collaborative working among manufacturing enterprises. Nevertheless, resource management in MG is much more complicated than that in other grid applications due to the geographically distributed manufacturing resources, which range from CAD, CAPP and CAE to various kinds of machine tools. With the interaction of manufacturing grid information service (MGIS, developed by ourselves) and globus resource allocation manager (GRAM, provided by GT3), a resource management framework is presented to perform the functions of resource encapsulation, registry, discovery and monitoring. Furthermore, the application architecture and an example are depicted to illustrate the utilization of the resource management system.
文摘Acute pancreatitis(AP)is a serious condition presenting catastrophic consequences.In severe AP,the mortality rate is high,and some patients initially diagnosed with mild-to-moderate AP can progress to a life-threatening severe state.Treatment of AP has evolved over the years.Drainage was the first surgical procedure performed for AP;however,later,surgical approaches were replaced by more conservative approaches due to the availability of advanced medical care and improved understanding of the course of AP.Currently,surgery is used to manage several complications of AP,such as pseudocysts,pancreatic fistulas,and biliary tract obstruction.Patients who are unresponsive to conservative treatment or have complications are typically considered for surgical intervention.This review focuses on the surgical approaches(endoscopic,percutaneous,and open)that have been established in recent studies to treat this acute condition and summarizes the common management guidelines for AP,discussing the relevant indications,significance,and complications.It is evident that despite their reduced involvement,surgeons lead the multidisciplinary care of patients with AP;however,given the gaps in existing knowledge,more research is required to standardize surgical protocols for AP.
基金National Nature Science Foundation of China(No.60534020)Cultivation Fundation of the Key Scientific and Technical Innovation Project from Ministry of Education of China(No.706024)International Science Cooperation Foundation of Shanghai,China(No.061307041)
文摘Traditional SNMP-based network management can not deal with the task of managing large-scaled distributed network,while policy-based management is one of the effective solutions in network and distributed systems management.However,cross-vendor hardware compatibility is one of the limitations in policy-based management.Devices existing in current network mostly support SNMP rather than Common Open Policy Service(COPS)protocol.By analyzing traditional network management and policy-based network management,a scalable network management framework is proposed.It is combined with Internet Engineering Task Force(IETF)framework for policy-based management and SNMP-based network management.By interpreting and translating policy decision to SNMP message,policy can be executed in traditional SNMP-based device.
文摘Steel 20Mn23AlV is a type of high aluminum steel with a very low ladle free-opening rate. The aluminum composition of 20Mn23AlV ranges from 1.6% to 2.45% ,which is significantly higher than other types of steel. According to the real condition of 40 t ladle in steel-making plant of Baosteel Special Steel Company, previous works show that the key factors affecting the ladle free-opening rate of high aluminum steel in continuous casting are:sand material, accessories baking, ladle nozzle cleaning, the process and amount of adding sand, and the rate of argon stirring during refining. Therefore, improving the ladle filler sand quality, baking all of the raw materials, controlling the addition of ladle filler sand, cleaning the ladle nozzle, and optimizing argon stirring during the refining process can resolve the problem of a low ladle free-opening rate of high aluminum steel caused by the long ladle time of liquid steel.
文摘A brief outline of Energy Management System (EMS) in China is given and OPEN-2000 EMS, combined with the novel technique of computer science, is introduced. The system has been developed by Power System Control Division of NARI and put into operation in the middle of 1998.
文摘The authors designed an ecological storm water system in a residential area to replace the conventional underground channels for the collection of storm water so as to reduce the nutrients and sediments discharged. This system contains natural sub-creeks as drainage channels discharging overflow to nearby creeks, an open green trench, a storage pond, and natural sub-creeks. The sub -creeks were designed to be integrated into community landscape, which not only increases the efficiency of water usage, but also improves the aesthetic qualities of the community residence area as required by Agenda 21. This research proved the feasibility of an open storm water collection and utilization system for the design of a community water system.
基金supported by the National Natural Science Foundation of China (NSFC,Grant Nos.11473001,11233004,11078006,11633009 and 11273067)the Minor Planet Foundation of Purple Mountain Observatory+2 种基金supported by the National Key Basic Research Program of China (2014CB845700)the China Postdoctoral Science Foundation (Grant No.2017M610695)supported by Special Funding for Advanced Users,budgeted and administrated by the Center for Astronomical Mega-Science,Chinese Academy of Sciences
文摘The Xuyi Schmidt Telescope Photometric Survey of the Galactic Anti-center(XSTPS-GAC)is a photometric sky survey that covers nearly 6000 deg^2 towards the Galactic Anti-center(GAC) in the g,r,i bands. Half of its survey field is located on the Galactic Anti-center disk,which makes XSTPSGAC highly suitable to search for new open clusters in the GAC region. In this paper,we report new open cluster candidates discovered in this survey,as well as properties of these open cluster candidates,such as age,distance and reddening,derived by isochrone fitting in the color-magnitude diagram(CMD).These open cluster candidates are stellar density peaks detected in the star density maps by applying the method from Koposov et al. Each candidate is inspected in terms of its true color image composed from three XSTPS-GAC band images. Then its CMD is checked,in order to identify whether the central region stars have a clear isochrone-like trend differing from background stars. The parameters derived from isochrone fitting for these candidates are mainly based on three band photometry of XSTPS-GAC.Moreover,when these new candidates are able to be seen clearly in 2 MASS data,their parameters are also derived based on the 2 MASS(J-H,J) CMD. There are a total of 320 known open clusters rediscovered and 24 new open cluster candidates discovered in this work. Furthermore,the parameters of these new candidates,as well as another 11 previously known open clusters,are properly determined for the first time.
文摘It has been found that there are marked errors in the value of valid opening size of heat-bonded nonwoven fabrics between theoretical calculations and engineering measurements. A new modified theoretical model is advanced in this paper. The equivalent diameter of the pore of a fibre web is used to calculate the valid opening size instead of the maximum diameter of inscribed circle used, because the fibres in practical fibre webs are flexible elastomers with definite diameters and the pore of fibre web may produce deformation in screening teat and engineering usage. The results show that the theoretical calculations coincide well with the engineering measurements. This method offers a theoretical basis for computer simulation to the performance of filters of heatbonded nonwoven fabrics.
基金supported by the National Natural Science Foundation of China(NSFC,Grant No.11403004)
文摘This paper presents a preliminary test of the k-th nearest neighbor distance (KNND) method for detecting nearby open clusters based on Gaia-DR1. We select 38 386 nearby stars (〈 100 pc) from the Gaia-DR1 catalog, and then use the KNND method to detect overdense regions in three-dimensional space. We find two overdense regions (the Hyades and Coma Berenices (Coma Ber) open clusters), and obtain 57 reliable cluster members. Based on these cluster members, the distances to the Hyades and Coma Ber clusters are determined to be 46.0±0.2 and 83.5±0.3 pc, respectively. Our results demonstrate that the KNND method can be used to detect open clusters based on a large volume of astrometry data.
文摘<strong>Purpose of Review:</strong> The management of eye injuries is both difficult and argumentative. This study attempts to highlight the management of ocular trauma using currently available information in the literature and author experience. This review presents a workable framework from the first presentation, epidemiology, classification, investigations, management principles, complications, prognostic factors, final visual outcome and management debates. <strong>Review Findings:</strong> Mechanical ocular trauma is a leading cause of monocular blindness and possible handicap worldwide. Among several classification systems, the most widely accepted is Birmingham Eye Trauma Terminology (BETT). Mechanical ocular trauma is a topic of unsolved controversy. Patching for corneal abrasion, paracentesis for hyphema, the timing of cataract surgery and intraocular lens implantation are all issues in anterior segment injuries. Regarding posterior segment controversies, the timing of vitrectomy, use of prophylactic cryotherapy, the necessity of intravitreal antibiotics in the absence of infection, the use of vitrectomy vs vitreous tap in traumatic endophthalmitis is the issues. The pediatric age group needs to be approached by a different protocol due to the risk of amblyopia, intraocular inflammation, and significant vitreoretinal adhesions. The various prognostic factors have a role in the final visual outcome. B scan is used to exclude R.D, Intraocular foreign body (IOFB), and vitreous haemorrhage in hazy media. Individual surgical strategies are used for every patient according to the classification and extent of the injuries. <strong>Conclusion:</strong> This article examines relevant evidence on the management challenges and controversies of mechanical trauma of the eye and offers treatment recommendations based on published research and the authors’ own experience.
文摘BACKGROUND Bile leakage is a common and serious complication of open hepatectomy for the treatment of biliary tract cancer.AIM To evaluate the incidence,risk factors,and management of bile leakage after open hepatectomy in patients with biliary tract cancer.METHODS We retrospectively analyzed 120 patients who underwent open hepatectomy for biliary tract cancer from February 2018 to February 2023.Bile leak was defined as bile drainage from the surgical site or drain or the presence of a biloma on imaging.The incidence,severity,timing,location,and treatment of the bile leaks were recorded.The risk factors for bile leakage were analyzed using univariate and multivariate logistic regression analyses.RESULTS The incidence of bile leak was 16.7%(20/120),and most cases were grade A(75%,15/20)according to the International Study Group of Liver Surgery classification.The median time of onset was 5 d(range,1-14 d),and the median duration was 7 d(range,2-28 d).The most common location of bile leakage was the cut surface of the liver(70%,14/20),followed by the anastomosis site(25%,5/20)and the cystic duct stump(5%,1/20).Most bile leaks were treated conservatively with drainage,antibiotics,and nutritional support(85%,17/20),whereas some required endoscopic retrograde cholangiopancreatography with stenting(10%,2/20)or percutaneous transhepatic cholangiography with drainage(5%,1/20).Risk factors for bile leakage include male sex,hepatocellular carcinoma,major hepatectomy,blood loss,and blood transfusion.CONCLUSION Bile leakage is a frequent complication of open hepatectomy for biliary tract cancer.However,most cases are mild and can be conservatively managed.Male sex,hepatocellular carcinoma,major hepatectomy,blood loss,and blood transfusion were associated with an increased risk of bile leak.