In order to solve the urgent problem of how to manage and sustain highway tunnels with advanced information technology with the background of the rapid development in the modem traffic, and achieve the cost- effective...In order to solve the urgent problem of how to manage and sustain highway tunnels with advanced information technology with the background of the rapid development in the modem traffic, and achieve the cost- effectiveness optimal principle objectives under the premise of guaranteeing a smooth flow of traffic; a highway tunnel maintenance and management system framework and the key modules were proposed. First, the determined highway tunnel condition assessment index system was established according to the result of expert consulting forms. Secondly, the tunnel diseases, the corresponding maintenance measurements, and many-to-many relationship between diseases and maintenance measurements were introduced. Then, three kinds of 0-1 integer programming models were built according to different tunnel operators＇ needs in the optimization decision module. Finally, the further development and implementation of the system was prospected. The research results can provide references to tunnel researchers and managers.展开更多
AIM To analyse the clinical features of patients with the serrated lesions in the upper gastrointestinal tract(UPGI) tract.METHODS Patients who underwent routine esophagogastroduodenoscopy(EGD) at the Digestive Endosc...AIM To analyse the clinical features of patients with the serrated lesions in the upper gastrointestinal tract(UPGI) tract.METHODS Patients who underwent routine esophagogastroduodenoscopy(EGD) at the Digestive Endoscopy Centre of General Hospital, Tianjin Medical University between january 2011 and December 2015 were consecutively recruited. Patients with UPGI serrated lesions were consecutively identified. The patients' demographics and histopathology were recorded. The colorectal findings for patients who underwent colonoscopy simultaneously or within six months were also extracted from the colonoscopy database. In addition, we analyseddifferences in colorectal neoplasia detection between the study patients and randomly selected patients matched for age and gender who did not exhibit serrated lesions and who also underwent colonoscopy in the same period.RESULTS A total of 21 patients out of 98746 patients(0.02%) who underwent EGD were confirmed to have serrated lesions with predominantly crenated, sawtooth-like configurations. The mean age of the 21 patients was(55.3 ± 17.2) years, and 11 patients were male(52.4%). In terms of the locations of the serrated lesions, 17 were found in the stomach(including 3 in the cardia, 9 in the corpus and 5 in the antrum), 3 were found in the duodenum, and 1 was found in the esophagus. Serrated lesions were found in different mucosal lesions, with 14 lesions were detected in polyps(8 hyperplastic polyps and 6 serrated adenomas with low grade dysplasia), 3 detected in Ménétrier gastropathy, 3 detected in an area of inflammation or ulcer, and 1 detected in the intramucosal carcinoma of the duodenum. In addition, colonoscopy data were available for 18 patients, and a significantly higher colorectal adenoma detection rate was observed in the UPGI serrated lesions group than in the randomly selected age- and gender-matched group without serrated lesions who also underwent colonoscopy in the same period(38.9% vs 11.1%, OR = 5.091, 95%CI: 1.534-16.890, P = 0.010). The detection rate of advanced adenoma was also higher in the UPGI serrated lesions group(22.2% vs 4.2%, OR = 6.571, 95%CI: 1.322-32.660, P = 0.028).CONCLUSION Serrated lesions in the UPGI were detected in various mucosal lesions with different pathological morphologies. Moreover colonoscopy is recommended for the detection of concurrent colorectal adenoma for these patients.展开更多
The soft rock's heterogeneity and nonlinear mechanical behavior cause extremely difficult maintenance on the soft rock roadway. Aiming at the asymmetric deformation and destruction phenomenon appearing after excav...The soft rock's heterogeneity and nonlinear mechanical behavior cause extremely difficult maintenance on the soft rock roadway. Aiming at the asymmetric deformation and destruction phenomenon appearing after excavating and supporting the 7101 air return way in Meihe mine, this paper comprehensively adopted a variety of methods to analyze the roadway surrounding rock deformation rule, obtaining the roadway surrounding rock stress and plastic zone distribution rule under no supporting condition and the roadway surrounding rock deformation features under original symmetric supporting condition.Furthermore, this paper revealed the catastrophe mechanism, and proposed the concept of ‘‘weak structure'' and the disaster countermeasure of ‘‘overall stabilizing the roadway and strengthening the support of weak structure''. The industrial test shows that the disaster control technology can realize the coordination deformation of the supporting structure and roadway surrounding rock, thus significantly controlling the deformation of roadway surrounding rock.展开更多
Studied the changes of heat physical parameters, gas concentration of O_2, CO,CH_4 and H_2, and temperature through full scale wood fire experiments in a tunnel and simulationby FLUNET, a kind of computational fluid d...Studied the changes of heat physical parameters, gas concentration of O_2, CO,CH_4 and H_2, and temperature through full scale wood fire experiments in a tunnel and simulationby FLUNET, a kind of computational fluid dynamics software.The results showthat the wood fire experiment and simulation are both oxygen-enriched combustions,which show that the simulation results coincide with the experiment.The results also provethat it is difficult for oxygen-enriched combustion to cause secondary disasters.Somesuggestions were put forward to prevent the occurrence of secondary disasters effectively.展开更多
Noninvasive monitoring capsule for gastrointestinal tract can De swauowed by patient.It is of great importance for the physician to monitor the precise position of capsule in gastrointestinal tract. The authors invest...Noninvasive monitoring capsule for gastrointestinal tract can De swauowed by patient.It is of great importance for the physician to monitor the precise position of capsule in gastrointestinal tract. The authors investigated a novel method for it. Using three coils with DC current to excite magnetic field and one triaxial magnetoresistive sensor to measure the excited magnetic vectors, they tried to solve the problem. The authors provided the localization principle of the method and analyzed it by an experiment, too. The method may be applied in practice in the future though it is still immature now.展开更多
Marine pipeline damage subjected to dropped objects from platforms or supply vessels is analyzed to introduce an easy and applicable approach to investigating the damage induced by impact load from drop weight. A prac...Marine pipeline damage subjected to dropped objects from platforms or supply vessels is analyzed to introduce an easy and applicable approach to investigating the damage induced by impact load from drop weight. A practical engineering example was presented and analyzed using the commercial program 'ANSYS/LS-DYNA', which is a powerful tool with an explicit dynamic solver. And rational agreement of the results with previous works was obtained. The suggested procedure might be taken as a checking analysis of the protection measures of pipelines in addition to the general risk assessment method.展开更多
Various physical parameters, including gas concentrations (O2, CO, CH4, and H2) and temperatures at dif- ferent air velocities, were determined for full scale wood fires in the Chongqing Coal Research Institute fire t...Various physical parameters, including gas concentrations (O2, CO, CH4, and H2) and temperatures at dif- ferent air velocities, were determined for full scale wood fires in the Chongqing Coal Research Institute fire test tunnel. Both experimental measurements and numerical simulations are discussed. The numer- ical analysis was performed with the computational fluid dynamics software package ''FLUENT''. The results show that the experimental data agree with the simulation results. The results verify that Roberts' theory of burning is correct. They also prove that the air velocity is the key factor that determines the type of combustion. Also, it is shown that secondary disasters are unlikely for oxygen rich combustion with a limited fire load.展开更多
基金The US National Science Foundation(No.CM M I-0408390,CM M I-0644552)the National Natural Science Foundation of China(No.U1134206,51250110075,51150110478)+1 种基金the Western Project of M inistry of Communications of China(No.0901005C)the Natural Science Foundation of Jiangsu Province(No.BK200910046)
文摘In order to solve the urgent problem of how to manage and sustain highway tunnels with advanced information technology with the background of the rapid development in the modem traffic, and achieve the cost- effectiveness optimal principle objectives under the premise of guaranteeing a smooth flow of traffic; a highway tunnel maintenance and management system framework and the key modules were proposed. First, the determined highway tunnel condition assessment index system was established according to the result of expert consulting forms. Secondly, the tunnel diseases, the corresponding maintenance measurements, and many-to-many relationship between diseases and maintenance measurements were introduced. Then, three kinds of 0-1 integer programming models were built according to different tunnel operators＇ needs in the optimization decision module. Finally, the further development and implementation of the system was prospected. The research results can provide references to tunnel researchers and managers.
基金Supported by the National Natural Science Foundation of China,No.81300272,No.81470796(to Cao HL)and No.81570478(to Wang BM)
文摘AIM To analyse the clinical features of patients with the serrated lesions in the upper gastrointestinal tract(UPGI) tract.METHODS Patients who underwent routine esophagogastroduodenoscopy(EGD) at the Digestive Endoscopy Centre of General Hospital, Tianjin Medical University between january 2011 and December 2015 were consecutively recruited. Patients with UPGI serrated lesions were consecutively identified. The patients' demographics and histopathology were recorded. The colorectal findings for patients who underwent colonoscopy simultaneously or within six months were also extracted from the colonoscopy database. In addition, we analyseddifferences in colorectal neoplasia detection between the study patients and randomly selected patients matched for age and gender who did not exhibit serrated lesions and who also underwent colonoscopy in the same period.RESULTS A total of 21 patients out of 98746 patients(0.02%) who underwent EGD were confirmed to have serrated lesions with predominantly crenated, sawtooth-like configurations. The mean age of the 21 patients was(55.3 ± 17.2) years, and 11 patients were male(52.4%). In terms of the locations of the serrated lesions, 17 were found in the stomach(including 3 in the cardia, 9 in the corpus and 5 in the antrum), 3 were found in the duodenum, and 1 was found in the esophagus. Serrated lesions were found in different mucosal lesions, with 14 lesions were detected in polyps(8 hyperplastic polyps and 6 serrated adenomas with low grade dysplasia), 3 detected in Ménétrier gastropathy, 3 detected in an area of inflammation or ulcer, and 1 detected in the intramucosal carcinoma of the duodenum. In addition, colonoscopy data were available for 18 patients, and a significantly higher colorectal adenoma detection rate was observed in the UPGI serrated lesions group than in the randomly selected age- and gender-matched group without serrated lesions who also underwent colonoscopy in the same period(38.9% vs 11.1%, OR = 5.091, 95%CI: 1.534-16.890, P = 0.010). The detection rate of advanced adenoma was also higher in the UPGI serrated lesions group(22.2% vs 4.2%, OR = 6.571, 95%CI: 1.322-32.660, P = 0.028).CONCLUSION Serrated lesions in the UPGI were detected in various mucosal lesions with different pathological morphologies. Moreover colonoscopy is recommended for the detection of concurrent colorectal adenoma for these patients.
基金provided by the National Natural Science Foundation of China(Nos.51204166 and51174195)the Jiangsu Province ordinary university graduate research innovation projects(No.CXZZ12_0954)
文摘The soft rock's heterogeneity and nonlinear mechanical behavior cause extremely difficult maintenance on the soft rock roadway. Aiming at the asymmetric deformation and destruction phenomenon appearing after excavating and supporting the 7101 air return way in Meihe mine, this paper comprehensively adopted a variety of methods to analyze the roadway surrounding rock deformation rule, obtaining the roadway surrounding rock stress and plastic zone distribution rule under no supporting condition and the roadway surrounding rock deformation features under original symmetric supporting condition.Furthermore, this paper revealed the catastrophe mechanism, and proposed the concept of ‘‘weak structure'' and the disaster countermeasure of ‘‘overall stabilizing the roadway and strengthening the support of weak structure''. The industrial test shows that the disaster control technology can realize the coordination deformation of the supporting structure and roadway surrounding rock, thus significantly controlling the deformation of roadway surrounding rock.
基金Supported by the National"Eleventh Five-Year"Key Scientific and Technological Support Program Project(2007BAK22B04)2008 Independent Task(SKLCRSM08B12)
文摘Studied the changes of heat physical parameters, gas concentration of O_2, CO,CH_4 and H_2, and temperature through full scale wood fire experiments in a tunnel and simulationby FLUNET, a kind of computational fluid dynamics software.The results showthat the wood fire experiment and simulation are both oxygen-enriched combustions,which show that the simulation results coincide with the experiment.The results also provethat it is difficult for oxygen-enriched combustion to cause secondary disasters.Somesuggestions were put forward to prevent the occurrence of secondary disasters effectively.
基金Supported by the High Technology Research and Development Programme of China （ No. 2004AA404013） and the National Natural Science Foundation of China （No. 30270382）.
文摘Noninvasive monitoring capsule for gastrointestinal tract can De swauowed by patient.It is of great importance for the physician to monitor the precise position of capsule in gastrointestinal tract. The authors investigated a novel method for it. Using three coils with DC current to excite magnetic field and one triaxial magnetoresistive sensor to measure the excited magnetic vectors, they tried to solve the problem. The authors provided the localization principle of the method and analyzed it by an experiment, too. The method may be applied in practice in the future though it is still immature now.
文摘Marine pipeline damage subjected to dropped objects from platforms or supply vessels is analyzed to introduce an easy and applicable approach to investigating the damage induced by impact load from drop weight. A practical engineering example was presented and analyzed using the commercial program 'ANSYS/LS-DYNA', which is a powerful tool with an explicit dynamic solver. And rational agreement of the results with previous works was obtained. The suggested procedure might be taken as a checking analysis of the protection measures of pipelines in addition to the general risk assessment method.
基金Financial support for this work provided by the National"Eleventh Five-Year" Key Scientific and Technological Support[Program (No. 2007BAK22B04)2008 independent task (No.SKLCRSM08B12)
文摘Various physical parameters, including gas concentrations (O2, CO, CH4, and H2) and temperatures at dif- ferent air velocities, were determined for full scale wood fires in the Chongqing Coal Research Institute fire test tunnel. Both experimental measurements and numerical simulations are discussed. The numer- ical analysis was performed with the computational fluid dynamics software package ''FLUENT''. The results show that the experimental data agree with the simulation results. The results verify that Roberts' theory of burning is correct. They also prove that the air velocity is the key factor that determines the type of combustion. Also, it is shown that secondary disasters are unlikely for oxygen rich combustion with a limited fire load.
