Study on spatial temporal model in property management information system

Time is an important dimension for information in the geographical information system. Data, such as the historical state of target property space and related events causing the state to be changed, should be saved as important files. This should be applied to property management. This paper designs and constructs a spatial temporal model, which is suitable to the property data changing management and spatial temporal query by analyzing the basic types and characteristics of property management spatial changing time and date. This model uses current and historical situational layers to organize and set up the relationship between current situation data and historical dates according to spatial temporal topological relations in property entities. By using Map Basic, housing property management and spatial query is realized.

TRPIV measurement of turbulent coherent structures in a drag-reducing flow by polymers

Fully developed turbulent flow fields with and without polymer solution at the same Reynolds number were measured by time-resolved particle image velocimetry （TRPIV） in a water channel to investigate the mechanism of drag-reducing solution from the view of coherent structures manipulation. The streamwise mean velocity and Reynolds stress profiles in the solution were compared with those in water. After adding the polymer solution, the Reynolds stress in the near-wall area decreases significantly. The result relates tightly to the decease of the coherent structures＇ bursting. The spatial topology of coherent structures during bursts has been extracted by the new mu-level criterion based on locally averaged velocity structure function. The effect of polymers on turbulent coherent structures mainly reflects in the intensity, not in the shape. In the solution, it is by suppressing the coherent structures that the wall friction is reduced.

Topological phase in one-dimensional Rashba wire

We study the possible topological phase in a one-dimensional（1D） quantum wire with an oscillating Rashba spin–orbital coupling in real space. It is shown that there are a pair of particle–hole symmetric gaps forming in the bulk energy band and fractional boundary states residing in the gap when the system has an inversion symmetry. These states are topologically nontrivial and can be characterized by a quantized Berry phase ±π or nonzero Chern number through dimensional extension. When the Rashba spin–orbital coupling varies slowly with time, the system can pump out 2 charges in a pumping cycle because of the spin flip effect. This quantized pumping is protected by topology and is robust against moderate disorders as long as the disorder strength does not exceed the opened energy gap.

Spatiotemporal graph queries on geographic databases under a conceptual abstraction scale

Visual queries assist non-expert users to extract information from spatial databases in an intuitive and natural approach,making Geographic information systems comprehensive and efficient for a wide range of applications.A common visual means of querying takes the form of drawings or graphs,under which many spatial ambiguity and translation errors rise.In this study,common query attributes extracted from user graphs such as spatial topology,size,cardinality,and proximity are regarded under a conceptual moderation scheme.Thus,the system/user may concentrate on various conceptual combinations of information.Furthermore,time is incorporated to support spatiotemporal queries for changing scenes and moving objects.Arbitrary,relative,and absolute scaling is possible according to the data-set and application at hand.The theoretic approach is implemented under a prototype user interface system,called ShapeController.Under this prototype,a user may extract scene-based relations in an automatically inferred fashion,or include single object-oriented relations when all possible relations seem redundant.Finally,a natural language description of the query is extracted upon which the user may select the desired query relations.Experimentation on a spatial database demonstrates the concepts of predefined draw objects,scaling relaxation,conceptual abstraction,and scene,object-and textual-oriented transitions that promote query expressiveness and restrain ambiguities.

Altered topological properties in the heritable schizophrenic brain

It is well established that complex networks are responsible for the high-level information processing in the human brain.The topology of complex networks allows efficient dynamic interactions between spatially distinct brain areas,which may be studied by analyzing the topological