Fenzhen Su - Profile on Academia.edu (original) (raw)
Papers by Fenzhen Su
Spatial and temporal changes and the driving forces of coastline in China Bohai Gulf in recent 30 years
2011 19th International Conference on Geoinformatics, 2011
Temp-spatial Patterns Extracting and Analysis of Sea Surface Warm Front of Kuroshio Based on Multi-Temporal RS Images and MGIS
Geo-information Science, 2009
Geo-event association rule discovery model based on rough set with marine fishery application
IEEE International IEEE International IEEE International Geoscience and Remote Sensing Symposium, 2004. IGARSS '04. Proceedings. 2004, 2004
... According to different geo-events, or different themes in a same geo-event, the neighborhood ... more ... According to different geo-events, or different themes in a same geo-event, the neighborhood may be defined as different shape, director with distance or resolution. 2.2. ... 3.1Research area and the data The study area (fig.2) lies in Dasha area, the south of the Yellow Sea. ...
Sea surface temperature and purse net productivity in East China Sea
IGARSS 2000. IEEE 2000 International Geoscience and Remote Sensing Symposium. Taking the Pulse of the Planet: The Role of Remote Sensing in Managing the Environment. Proceedings (Cat. No.00CH37120), 2000
Temperature, as one of the main factors, is thought to play a dominant role in determining the sp... more Temperature, as one of the main factors, is thought to play a dominant role in determining the spatial and temporal distribution of fish centers and fishing grounds. For many species of marine fish, research has provided much information about their spawning, feeding habitats and migrations; however, such information is always empirical. In order to investigate the relationship between sea surface
Representation of Uncertain Objects and Research on Their Spatio-temporal Topologies
Geo-information Science, 2009
Chinese Geographical Science, 2015
Changes in the frequency and intensity of extreme climate events because of anthropogenic induced... more Changes in the frequency and intensity of extreme climate events because of anthropogenic induced climate change have been documented in many scientific papers. The climate extremes usually analysed until now are those related to heavy precipitation, droughts, high temperatures expressed by various indices. It is known that, especially during summer, extreme weather conditions, when high temperatures are associated to high relative humidity, contribute to a high human discomfort. The index linking the two climate variables (air temperature and relative humidity) is commonly called "thermal stress index, temperature-humidity" (ITU), which has been less analysed, at least for Romania. ITU index is defined by the relationship ITU=(TA*1.8+32)-(0.55-0.55*UM/100)* [(TA*1.8+32)-58, where Ta is air temperature and UM is relative humidity. This study presents the characteristics of spatial and temporal variability of monthly/seasonal ITU values over the period 1961-2010. The monthly averages for May-September and summer averages (June-August) for 60 stations with complete observations, were considered. The statistical significance of linear trends and shifts in the mean (given by the Mann Kendall and Pettitt tests, respectively) as well as spatial mode of variability (using EOF analysis) are performed. The summer frequency of ITU values exceeding 80 units (threshold considered to be responsible for high impact on human health) has been also analysed using the same statistical techniques. The results reveal statistically significant increasing trends (5% level) for the monthly ITU averages for May to August over the entire country and slightly decreasing for September (not statistically significant). The highest trends were identified for July (3.12 units/50 years) and August (3.25 units/50 years). An increasing trend was also identified for the summer frequency of ITU values exceeding 80 units with highest values over the extra-Carpathian regions, reaching 16-25 days/50 years in the South of Romania (Danube Plain). A strong increase shift was identified around 1987 year, which is in agreement with the shift in the extreme temperature indices in Romania (presented in other study). The trends in relative humidity will be also explored. The EOF analysis reveals that EOF1 pattern, showing same sign over the entire country, explains 89% from the total observed variance. This result shows that a large-scale mechanism is responsible for the summer ITU variability. The correlation between the time series associated to EOF1 (PC1) of the summer ITU and PC1 of the T850 (large-scale temperature at 850 hPa) was performed, showing a significant strong correlation, as found for the extreme temperatures. This result shows a possible physical explanation of the ITU increasing trend. Other predictors will be also explored.
Analysis of 3D Virtual Globe's Applicability in Marine Information and the Prototype System Research
Geo-information Science, 2010
Chinese Journal of Oceanology and Limnology, 2010
With long-term marine surveys and research, and especially with the development of new marine env... more With long-term marine surveys and research, and especially with the development of new marine environment monitoring technologies, prodigious amounts of complex marine environmental data are generated, and continuously increase rapidly. Features of these data include massive volume, widespread distribution, multiple-sources, heterogeneous, multi-dimensional and dynamic in structure and time. The present study recommends an integrative visualization solution for these data, to enhance the visual display of data and data archives, and to develop a joint use of these data distributed among different organizations or communities. This study also analyses the web services technologies and defines the concept of the marine information gird, then focuses on the spatiotemporal visualization method and proposes a process-oriented spatiotemporal visualization method. We discuss how marine environmental data can be organized based on the spatiotemporal visualization method, and how organized data are represented for use with web services and stored in a reusable fashion. In addition, we provide an original visualization architecture that is integrative and based on the explored technologies. In the end, we propose a prototype system of marine environmental data of the South China Sea for visualizations of Argo floats, sea surface temperature fields, sea current fields, salinity, in-situ investigation data, and ocean stations. An integration visualization architecture is illustrated on the prototype system, which highlights the process-oriented temporal visualization method and demonstrates the benefit of the architecture and the methods described in this study.
A web services based integrative platform for marine information in South China Sea
2011 19th International Conference on Geoinformatics, 2011
This contribution presents a service-oriented application that addresses the issues of marine inf... more This contribution presents a service-oriented application that addresses the issues of marine information accessibility and enables scientists to implement ocean models online. The application serves four primary functions: 1) Integrate in-situ and satellite observation data and model results. 2) Produce value-added products by combing multiple data sources. 3) Supply various methods to access and visualize the data. 4) Provide on-demand
2010 IEEE International Geoscience and Remote Sensing Symposium, 2010
Great changes of coastal wetland in Pearl River Estuary have taken placed since 1970s. To investi... more Great changes of coastal wetland in Pearl River Estuary have taken placed since 1970s. To investigate the spatial and temporal variations of coastal wetland in Pearl River Estuary, Landsat-MSS images in 1975 and Landsat-TM images in 1995 were processed, and a wetland database of these three periods was established based on these satellite images. Since the changes of coastal wetland had significant relationship with coastline changes, a model for coastline changes detection was established. By means of GIS and RS, temporal and spatial changes of coastal wetland in Pear River Estuary were studied in this work. The result showed that: (1) During period of 1975~1995, coastal wetland area decreased by 3.3%, and decreased by 18.3% during 1995~2005; (2) Among 6 administrative districts of the study area, wetland dynamic degree could be sorted in a descending order as: Zhuhai, Shenzhen, Macao, Dongguan, Zhongshan and Guangzhou; (3) The centroids of wetland in Pearl River Estuary coastal zone moved 0.6km in the north direction during 1975~1995, and 6.1km in the southeast direction during 1995~2005; (4) Due to the changes of coastlines in Pearl River Estuary, the area of sea reclamation during 1975~2005 in Zhuhai, Macao, Zhongshan, Guangzhou Dongguan, Shenzhen was 12439.29, 502.60, 2946.45, 5372.21, 1815 and 6317.88 hectares respectively; (5) Average distance of coastline changes during 1975~2005 was 651.2m in Zhuhai, 187.1m in Macao, 1304.7m in Zhongshan, 802.8m in Guangzhou, 193.3m in Dongguan and 523.1m in Shenzhen. To conclude, this work demonstrates the importance of satellite images to monitor the temporal and spatial changes of coastal wetland.
The Effect of Jar Holding Posture on Finger Force and Torque during a Jar-Opening Task for Young Females
Packaging Technology and Science, 2014
ABSTRACT Many young females have difficulty opening jars. Although previous studies have attempte... more ABSTRACT Many young females have difficulty opening jars. Although previous studies have attempted to clarify the body posture effect during such a task, the experiments therein focused on a single digit or actions with unnatural finger positions and were further restricted to upper extremity postures. A further study is required to investigate the fingers’ coordination, as well as each subject's natural and self-selected upper extremity posture and finger grasp location when opening a jar. This study focused on the forces and coordination of the right hand fingers during a jar opening movement under both vertical and free-way opening postures. A jar simulator was set up to record the forces applied by finger groups (the thumb, the index–middle finger group, and the ring–little finger group) of the right hand. A self-selected finger position and free-arm posture of each subject were allowed. Results show that the force vectors of the finger groups were all in the counterclockwise direction for both postures. The total force and overall torque of the right hand decreased in the vertical opening posture. The thumb produced greater tangential and resultant forces in the vertical opening posture. Despite normal forces being 1.82–3.54 times the tangential forces for both postures, no difference was found for the normal force to tangential force ratio for each finger group between the two opening postures. The index–middle finger group had similar torque contributions for both postures. The torque contribution of the thumb increased (26% and 21% for vertical and free-way posture, respectively), while the ring–little finger group torque contribution decreased (35% and 42% for vertical and free-way posture, respectively) in the vertical opening posture. As such, the free-way opening posture is the better strategy for young females to open a jar. Copyright © 2013 John Wiley & Sons, Ltd.
A temporal accessibility model for assessing the ability of search and rescue in Nansha Islands, South China Sea
Ocean & Coastal Management, 2014
ABSTRACT Time is an indispensable means in accessibility expression and also an important index o... more ABSTRACT Time is an indispensable means in accessibility expression and also an important index of the search and rescue (SAR) ability to a country. In this paper, a method for forecasting the location and probability of patrol vessel which is responsible for SAR on the sea is presented; and a temporal accessibility model for assessing the SAR ability of countries around South China Sea in Nansha is structured. In this study, 19 islands and cays in Nansha Islands are selected as rescue targets; eight ports in four countries around South China Sea are selected as SAR bases; patrol vessels belong to coast guard or maritime agency of countries around South China Sea whose displacement is over 1000 tons are selected as principal searchers and rescuers. Based on the density of ships passing the area and the distance from ports of each homeland, the distributions of patrol vessel which belongs to four countries around South China Sea are obtained. The SAR time of China, Vietnam, Malaysia and Philippines in Nansha were calculated based on the proposed method. The results indicated that due to the number of big patrol vessels, China Coast Guard is able to get to Nansha in minimum time, only half an hour for SAR; Vietnam gets second, one and a half hours; Malaysia gets third, 4.6 h; Philippines costs almost 7 h at the bottom of the list, because of the distance and the number of vessels. Taking consideration of the scattered distribution of islands, rocky coral reefs, bad weather and complex marine conditions, it is a very difficult job for SAR vessels. So it is necessary to set up several sub centers and shelters on appropriate islands or atolls in Nansha. And more importantly, how to enhance connection and coordination among countries around South China Sea, build harmonious and smooth SAR mechanisms or channels for cooperation, and improve the ability for solving emergency accidents in Nansha and even the whole South China Sea.
A physical Impulse-based approach to evaluate the exploitative intensity of Bay—A case study of Daya Bay in China
Ocean & Coastal Management, 2012
ABSTRACT The exploitative intensity evaluation of bays is meaningful for the ecological conservat... more ABSTRACT The exploitative intensity evaluation of bays is meaningful for the ecological conservation, future utilization and integrated management of bays in China; especially for the regions where the economic development is depending on the coastal exploitation. Nevertheless, the complexity of morphology and structure of bays make the study a little bit difficult. A physical impulse-based approach to evaluate the exploitative intensity of bay was put forward in this paper. First of all, the differentiation in morphological, spatial location and structure of bays were analyzed, and the bay was separated into geographical elements of axes and areas accordingly; secondly, the exploitation and utilization process was abstracted and assumed using physical principles; Thirdly, physical Impulse-based Model of exploitative intensity evaluation was build according to the Law of Momentum which can convert the process variable to state variable. Daya Bay of Guangdong province in China was taken as a case study, four key time indicating the construction of large coastal engineering near Daya Bay coast were selected, namely year 1986, 1991, 2001 and 2004. The exploitative intensities of each spatial element of Daya Bay during 1986–1991, 1991–2001, and 2001–2004 were calculated and analyzed. The results show that the exploitative intensity of intertidal flat in Daya Bay during the study time spans is highest. The potential applications, current limitations, and future challenges of the approach were discussed.
Uncertainty representation of ocean fronts based on fuzzy-rough set theory
Journal of Ocean University of China, 2008
Analysis of ocean fronts’ uncertainties indicates that they result from indiscernibility of their... more Analysis of ocean fronts’ uncertainties indicates that they result from indiscernibility of their spatial position and fuzziness of their intensity. In view of this, a flow hierarchy for uncertainty representation of ocean fronts is proposed on the basis of fuzzy-rough set theory. Firstly, raster scanning and blurring are carried out on an ocean front, and the upper and lower approximate sets, the indiscernible relation in fuzzy-rough theories and related operators in fuzzy set theories are adopted to represent its uncertainties, then they are classified into three sets: with members one hundred percent belonging to the ocean front, belonging to the ocean front’s edge and definitely not belonging to the ocean front. Finally, the approximate precision and roughness degree are utilized to evaluate the ocean front’s degree of uncertainties and the precision of the representation. It has been proven that the method is not only capable of representing ocean fronts’ uncertainties, but also provides a new theory and method for uncertainty representation of other oceanic phenomena.
Gait analysis after ankle arthrodesis
Gait & Posture, 2000
The purpose of this study was to employ a computerized motion analysis system to identify the eff... more The purpose of this study was to employ a computerized motion analysis system to identify the effect of ankle arthrodesis on the three-dimensional kinematic behavior of the rear and fore foot during level walking. A three-segment rigid body model was used to describe the motion of the foot and ankle. The results demonstrated that sagittal plane motion of the hindfoot was significantly decreased in the foot of patients having had ankle arthrodesis compared to normal subjects. The kinematic data indicated a generalized stiffness of the hindfoot on the involved foot in the sagittal plane. Sagittal plane movement in the forefoot and transverse plane movements in the hindfoot and forefoot increased in patients compared to controls.
Clinical Biomechanics, 2001
Elbow joint loading was evaluated during pushup exercises at various forearm rotations. Subjects ... more Elbow joint loading was evaluated during pushup exercises at various forearm rotations. Subjects were asked to perform pushup in various forearm rotations: neutral, 90 degrees internal rotation, and 90 degrees external rotation. Training with pushup exercise is good for the muscles and joints of the upper extremities. However, excessive shear forces on the elbow might lead to injuries to either normal trainees or to handicapped people, especially for those who rely on elbow prosthesis. The kinematics and kinetics of the elbow joint were investigated under various forearm rotations. The loading biomechanics of the elbow joint differed with various forearm rotations. It was noted that greater posterior and varus forces of the elbow are encountered with internal rotation of the hand position and, consequently, full forearm pronation. Pushup with hands in internally rotated position should be prevented so as to avoid excessive shear forces or moments. Knowledge of elbow kinematics and kinetics may be helpful in preventing injuries by reducing the elbow shear force with changes of forearm rotation.
Ecological Modelling, 2004
The interaction between environmental factors and the spatiotemporal dynamics of living organism ... more The interaction between environmental factors and the spatiotemporal dynamics of living organism is an important aspect in ecology. We describe here a data-mining approach-the spatiotemporal assignment mining model (STAMM)-to extract the spatiotemporal pattern, or assignment of environmental factors, which control the distribution of a living organism. In STAMM, the spatiotemporal assignment of environmental factors is expressed via neighbourhood rules which will reflect the fuzzy or uncertain prior knowledge about the relationship. The values of cells or points in the neighbourhood and the relationships are used to construct a decision table. Indices expressing the probabilities of the ecological association rules are recursively processed in order to determine the spatiotemporal assignment. These rules are objective assessments of our prior knowledge and they refine our knowledge and understanding of the ecosystem. As a case study, we used this model to study the temperature pattern which controls the assembling of fish in the Dasha area of the Yellow Sea in China.
Spatial and temporal changes and the driving forces of coastline in China Bohai Gulf in recent 30 years
2011 19th International Conference on Geoinformatics, 2011
Temp-spatial Patterns Extracting and Analysis of Sea Surface Warm Front of Kuroshio Based on Multi-Temporal RS Images and MGIS
Geo-information Science, 2009
Geo-event association rule discovery model based on rough set with marine fishery application
IEEE International IEEE International IEEE International Geoscience and Remote Sensing Symposium, 2004. IGARSS '04. Proceedings. 2004, 2004
... According to different geo-events, or different themes in a same geo-event, the neighborhood ... more ... According to different geo-events, or different themes in a same geo-event, the neighborhood may be defined as different shape, director with distance or resolution. 2.2. ... 3.1Research area and the data The study area (fig.2) lies in Dasha area, the south of the Yellow Sea. ...
Sea surface temperature and purse net productivity in East China Sea
IGARSS 2000. IEEE 2000 International Geoscience and Remote Sensing Symposium. Taking the Pulse of the Planet: The Role of Remote Sensing in Managing the Environment. Proceedings (Cat. No.00CH37120), 2000
Temperature, as one of the main factors, is thought to play a dominant role in determining the sp... more Temperature, as one of the main factors, is thought to play a dominant role in determining the spatial and temporal distribution of fish centers and fishing grounds. For many species of marine fish, research has provided much information about their spawning, feeding habitats and migrations; however, such information is always empirical. In order to investigate the relationship between sea surface
Representation of Uncertain Objects and Research on Their Spatio-temporal Topologies
Geo-information Science, 2009
Chinese Geographical Science, 2015
Changes in the frequency and intensity of extreme climate events because of anthropogenic induced... more Changes in the frequency and intensity of extreme climate events because of anthropogenic induced climate change have been documented in many scientific papers. The climate extremes usually analysed until now are those related to heavy precipitation, droughts, high temperatures expressed by various indices. It is known that, especially during summer, extreme weather conditions, when high temperatures are associated to high relative humidity, contribute to a high human discomfort. The index linking the two climate variables (air temperature and relative humidity) is commonly called "thermal stress index, temperature-humidity" (ITU), which has been less analysed, at least for Romania. ITU index is defined by the relationship ITU=(TA*1.8+32)-(0.55-0.55*UM/100)* [(TA*1.8+32)-58, where Ta is air temperature and UM is relative humidity. This study presents the characteristics of spatial and temporal variability of monthly/seasonal ITU values over the period 1961-2010. The monthly averages for May-September and summer averages (June-August) for 60 stations with complete observations, were considered. The statistical significance of linear trends and shifts in the mean (given by the Mann Kendall and Pettitt tests, respectively) as well as spatial mode of variability (using EOF analysis) are performed. The summer frequency of ITU values exceeding 80 units (threshold considered to be responsible for high impact on human health) has been also analysed using the same statistical techniques. The results reveal statistically significant increasing trends (5% level) for the monthly ITU averages for May to August over the entire country and slightly decreasing for September (not statistically significant). The highest trends were identified for July (3.12 units/50 years) and August (3.25 units/50 years). An increasing trend was also identified for the summer frequency of ITU values exceeding 80 units with highest values over the extra-Carpathian regions, reaching 16-25 days/50 years in the South of Romania (Danube Plain). A strong increase shift was identified around 1987 year, which is in agreement with the shift in the extreme temperature indices in Romania (presented in other study). The trends in relative humidity will be also explored. The EOF analysis reveals that EOF1 pattern, showing same sign over the entire country, explains 89% from the total observed variance. This result shows that a large-scale mechanism is responsible for the summer ITU variability. The correlation between the time series associated to EOF1 (PC1) of the summer ITU and PC1 of the T850 (large-scale temperature at 850 hPa) was performed, showing a significant strong correlation, as found for the extreme temperatures. This result shows a possible physical explanation of the ITU increasing trend. Other predictors will be also explored.
Analysis of 3D Virtual Globe's Applicability in Marine Information and the Prototype System Research
Geo-information Science, 2010
Chinese Journal of Oceanology and Limnology, 2010
With long-term marine surveys and research, and especially with the development of new marine env... more With long-term marine surveys and research, and especially with the development of new marine environment monitoring technologies, prodigious amounts of complex marine environmental data are generated, and continuously increase rapidly. Features of these data include massive volume, widespread distribution, multiple-sources, heterogeneous, multi-dimensional and dynamic in structure and time. The present study recommends an integrative visualization solution for these data, to enhance the visual display of data and data archives, and to develop a joint use of these data distributed among different organizations or communities. This study also analyses the web services technologies and defines the concept of the marine information gird, then focuses on the spatiotemporal visualization method and proposes a process-oriented spatiotemporal visualization method. We discuss how marine environmental data can be organized based on the spatiotemporal visualization method, and how organized data are represented for use with web services and stored in a reusable fashion. In addition, we provide an original visualization architecture that is integrative and based on the explored technologies. In the end, we propose a prototype system of marine environmental data of the South China Sea for visualizations of Argo floats, sea surface temperature fields, sea current fields, salinity, in-situ investigation data, and ocean stations. An integration visualization architecture is illustrated on the prototype system, which highlights the process-oriented temporal visualization method and demonstrates the benefit of the architecture and the methods described in this study.
A web services based integrative platform for marine information in South China Sea
2011 19th International Conference on Geoinformatics, 2011
This contribution presents a service-oriented application that addresses the issues of marine inf... more This contribution presents a service-oriented application that addresses the issues of marine information accessibility and enables scientists to implement ocean models online. The application serves four primary functions: 1) Integrate in-situ and satellite observation data and model results. 2) Produce value-added products by combing multiple data sources. 3) Supply various methods to access and visualize the data. 4) Provide on-demand
2010 IEEE International Geoscience and Remote Sensing Symposium, 2010
Great changes of coastal wetland in Pearl River Estuary have taken placed since 1970s. To investi... more Great changes of coastal wetland in Pearl River Estuary have taken placed since 1970s. To investigate the spatial and temporal variations of coastal wetland in Pearl River Estuary, Landsat-MSS images in 1975 and Landsat-TM images in 1995 were processed, and a wetland database of these three periods was established based on these satellite images. Since the changes of coastal wetland had significant relationship with coastline changes, a model for coastline changes detection was established. By means of GIS and RS, temporal and spatial changes of coastal wetland in Pear River Estuary were studied in this work. The result showed that: (1) During period of 1975~1995, coastal wetland area decreased by 3.3%, and decreased by 18.3% during 1995~2005; (2) Among 6 administrative districts of the study area, wetland dynamic degree could be sorted in a descending order as: Zhuhai, Shenzhen, Macao, Dongguan, Zhongshan and Guangzhou; (3) The centroids of wetland in Pearl River Estuary coastal zone moved 0.6km in the north direction during 1975~1995, and 6.1km in the southeast direction during 1995~2005; (4) Due to the changes of coastlines in Pearl River Estuary, the area of sea reclamation during 1975~2005 in Zhuhai, Macao, Zhongshan, Guangzhou Dongguan, Shenzhen was 12439.29, 502.60, 2946.45, 5372.21, 1815 and 6317.88 hectares respectively; (5) Average distance of coastline changes during 1975~2005 was 651.2m in Zhuhai, 187.1m in Macao, 1304.7m in Zhongshan, 802.8m in Guangzhou, 193.3m in Dongguan and 523.1m in Shenzhen. To conclude, this work demonstrates the importance of satellite images to monitor the temporal and spatial changes of coastal wetland.
The Effect of Jar Holding Posture on Finger Force and Torque during a Jar-Opening Task for Young Females
Packaging Technology and Science, 2014
ABSTRACT Many young females have difficulty opening jars. Although previous studies have attempte... more ABSTRACT Many young females have difficulty opening jars. Although previous studies have attempted to clarify the body posture effect during such a task, the experiments therein focused on a single digit or actions with unnatural finger positions and were further restricted to upper extremity postures. A further study is required to investigate the fingers’ coordination, as well as each subject's natural and self-selected upper extremity posture and finger grasp location when opening a jar. This study focused on the forces and coordination of the right hand fingers during a jar opening movement under both vertical and free-way opening postures. A jar simulator was set up to record the forces applied by finger groups (the thumb, the index–middle finger group, and the ring–little finger group) of the right hand. A self-selected finger position and free-arm posture of each subject were allowed. Results show that the force vectors of the finger groups were all in the counterclockwise direction for both postures. The total force and overall torque of the right hand decreased in the vertical opening posture. The thumb produced greater tangential and resultant forces in the vertical opening posture. Despite normal forces being 1.82–3.54 times the tangential forces for both postures, no difference was found for the normal force to tangential force ratio for each finger group between the two opening postures. The index–middle finger group had similar torque contributions for both postures. The torque contribution of the thumb increased (26% and 21% for vertical and free-way posture, respectively), while the ring–little finger group torque contribution decreased (35% and 42% for vertical and free-way posture, respectively) in the vertical opening posture. As such, the free-way opening posture is the better strategy for young females to open a jar. Copyright © 2013 John Wiley & Sons, Ltd.
A temporal accessibility model for assessing the ability of search and rescue in Nansha Islands, South China Sea
Ocean & Coastal Management, 2014
ABSTRACT Time is an indispensable means in accessibility expression and also an important index o... more ABSTRACT Time is an indispensable means in accessibility expression and also an important index of the search and rescue (SAR) ability to a country. In this paper, a method for forecasting the location and probability of patrol vessel which is responsible for SAR on the sea is presented; and a temporal accessibility model for assessing the SAR ability of countries around South China Sea in Nansha is structured. In this study, 19 islands and cays in Nansha Islands are selected as rescue targets; eight ports in four countries around South China Sea are selected as SAR bases; patrol vessels belong to coast guard or maritime agency of countries around South China Sea whose displacement is over 1000 tons are selected as principal searchers and rescuers. Based on the density of ships passing the area and the distance from ports of each homeland, the distributions of patrol vessel which belongs to four countries around South China Sea are obtained. The SAR time of China, Vietnam, Malaysia and Philippines in Nansha were calculated based on the proposed method. The results indicated that due to the number of big patrol vessels, China Coast Guard is able to get to Nansha in minimum time, only half an hour for SAR; Vietnam gets second, one and a half hours; Malaysia gets third, 4.6 h; Philippines costs almost 7 h at the bottom of the list, because of the distance and the number of vessels. Taking consideration of the scattered distribution of islands, rocky coral reefs, bad weather and complex marine conditions, it is a very difficult job for SAR vessels. So it is necessary to set up several sub centers and shelters on appropriate islands or atolls in Nansha. And more importantly, how to enhance connection and coordination among countries around South China Sea, build harmonious and smooth SAR mechanisms or channels for cooperation, and improve the ability for solving emergency accidents in Nansha and even the whole South China Sea.
A physical Impulse-based approach to evaluate the exploitative intensity of Bay—A case study of Daya Bay in China
Ocean & Coastal Management, 2012
ABSTRACT The exploitative intensity evaluation of bays is meaningful for the ecological conservat... more ABSTRACT The exploitative intensity evaluation of bays is meaningful for the ecological conservation, future utilization and integrated management of bays in China; especially for the regions where the economic development is depending on the coastal exploitation. Nevertheless, the complexity of morphology and structure of bays make the study a little bit difficult. A physical impulse-based approach to evaluate the exploitative intensity of bay was put forward in this paper. First of all, the differentiation in morphological, spatial location and structure of bays were analyzed, and the bay was separated into geographical elements of axes and areas accordingly; secondly, the exploitation and utilization process was abstracted and assumed using physical principles; Thirdly, physical Impulse-based Model of exploitative intensity evaluation was build according to the Law of Momentum which can convert the process variable to state variable. Daya Bay of Guangdong province in China was taken as a case study, four key time indicating the construction of large coastal engineering near Daya Bay coast were selected, namely year 1986, 1991, 2001 and 2004. The exploitative intensities of each spatial element of Daya Bay during 1986–1991, 1991–2001, and 2001–2004 were calculated and analyzed. The results show that the exploitative intensity of intertidal flat in Daya Bay during the study time spans is highest. The potential applications, current limitations, and future challenges of the approach were discussed.
Uncertainty representation of ocean fronts based on fuzzy-rough set theory
Journal of Ocean University of China, 2008
Analysis of ocean fronts’ uncertainties indicates that they result from indiscernibility of their... more Analysis of ocean fronts’ uncertainties indicates that they result from indiscernibility of their spatial position and fuzziness of their intensity. In view of this, a flow hierarchy for uncertainty representation of ocean fronts is proposed on the basis of fuzzy-rough set theory. Firstly, raster scanning and blurring are carried out on an ocean front, and the upper and lower approximate sets, the indiscernible relation in fuzzy-rough theories and related operators in fuzzy set theories are adopted to represent its uncertainties, then they are classified into three sets: with members one hundred percent belonging to the ocean front, belonging to the ocean front’s edge and definitely not belonging to the ocean front. Finally, the approximate precision and roughness degree are utilized to evaluate the ocean front’s degree of uncertainties and the precision of the representation. It has been proven that the method is not only capable of representing ocean fronts’ uncertainties, but also provides a new theory and method for uncertainty representation of other oceanic phenomena.
Gait analysis after ankle arthrodesis
Gait & Posture, 2000
The purpose of this study was to employ a computerized motion analysis system to identify the eff... more The purpose of this study was to employ a computerized motion analysis system to identify the effect of ankle arthrodesis on the three-dimensional kinematic behavior of the rear and fore foot during level walking. A three-segment rigid body model was used to describe the motion of the foot and ankle. The results demonstrated that sagittal plane motion of the hindfoot was significantly decreased in the foot of patients having had ankle arthrodesis compared to normal subjects. The kinematic data indicated a generalized stiffness of the hindfoot on the involved foot in the sagittal plane. Sagittal plane movement in the forefoot and transverse plane movements in the hindfoot and forefoot increased in patients compared to controls.
Clinical Biomechanics, 2001
Elbow joint loading was evaluated during pushup exercises at various forearm rotations. Subjects ... more Elbow joint loading was evaluated during pushup exercises at various forearm rotations. Subjects were asked to perform pushup in various forearm rotations: neutral, 90 degrees internal rotation, and 90 degrees external rotation. Training with pushup exercise is good for the muscles and joints of the upper extremities. However, excessive shear forces on the elbow might lead to injuries to either normal trainees or to handicapped people, especially for those who rely on elbow prosthesis. The kinematics and kinetics of the elbow joint were investigated under various forearm rotations. The loading biomechanics of the elbow joint differed with various forearm rotations. It was noted that greater posterior and varus forces of the elbow are encountered with internal rotation of the hand position and, consequently, full forearm pronation. Pushup with hands in internally rotated position should be prevented so as to avoid excessive shear forces or moments. Knowledge of elbow kinematics and kinetics may be helpful in preventing injuries by reducing the elbow shear force with changes of forearm rotation.
Ecological Modelling, 2004
The interaction between environmental factors and the spatiotemporal dynamics of living organism ... more The interaction between environmental factors and the spatiotemporal dynamics of living organism is an important aspect in ecology. We describe here a data-mining approach-the spatiotemporal assignment mining model (STAMM)-to extract the spatiotemporal pattern, or assignment of environmental factors, which control the distribution of a living organism. In STAMM, the spatiotemporal assignment of environmental factors is expressed via neighbourhood rules which will reflect the fuzzy or uncertain prior knowledge about the relationship. The values of cells or points in the neighbourhood and the relationships are used to construct a decision table. Indices expressing the probabilities of the ecological association rules are recursively processed in order to determine the spatiotemporal assignment. These rules are objective assessments of our prior knowledge and they refine our knowledge and understanding of the ecosystem. As a case study, we used this model to study the temperature pattern which controls the assembling of fish in the Dasha area of the Yellow Sea in China.