The lower Ordovician mid-assemblage Formations in the central Ordos Basin of China host prolific gas resources,and most hydrocarbon reserves are stored in naturally-fractured reservoirs.Thus,fracture pathway systems m...The lower Ordovician mid-assemblage Formations in the central Ordos Basin of China host prolific gas resources,and most hydrocarbon reserves are stored in naturally-fractured reservoirs.Thus,fracture pathway systems may have a significant impact on reservoir performance.This article focuses on the core-and laboratory-based characterization of fractures.Through the developmental degrees,extended scale,output state and filling characteristics of various types of fractures,the results show that there are three distinct fracture types:1)nearly vertical fractures,2)oblique fractures,and 3)horizontal fractures.Based on a systematic study of the characterization of reservoir space,the main geologic setting of natural gas accumulation and the regional tectonic background,type 1 is mainly driven by the tectonic formation mechanism,and type 3 and parts of low-angle fractures in type 2 are induced by the diagenetic formation mechanism.While recovered paleopressure for methane-rich aqueous inclusions trapped in fracture-filling cement indicates that the fracture opening and growth are consistent with gas maturation and charge and such high-angle fractures in type 2 are caused by the compound formation mechanism.The fractures to hydrocarbon accumulation may play a more significant role in improving the quality of reservoir porosity.Furthermore,connected fractures,dissolved pores and cavities together constitute the three-dimensional pore-cave-fracture network pathway systems,with faults serving as the dominant charge pathways of highly pressurized gas in the study area.Our results demonstrate that protracted growth of a pervasive fracture system is not only the consequence of various formation mechanisms but also intrinsic to quasi-continuous accumulation reservoirs.展开更多
The objective of the present work is characterizing some parameters in the lay phase in the lines of heavy broilers breeder Cobb Avian 48, Arbor Acres Plus and Ross 208, reared under the same commercial conditions in ...The objective of the present work is characterizing some parameters in the lay phase in the lines of heavy broilers breeder Cobb Avian 48, Arbor Acres Plus and Ross 208, reared under the same commercial conditions in the tropics. Monitored three batches of approximately 18,000 females each (one for each genetic type), from weeks 24 to 64, according to the conditions of handling and power described by the generic lines distribution companies. Although no differences were found for feed intake, Cobb Avian was presented a lower rate of feed conversion, being also that presented the highest percentage of implementation and production of incubables eggs, which meant that it was in line with the highest cumulative production of chickens by bird and week for tropical conditions studied. To adjust the lay data to a Gorssman model, in order to predict the parameters that characterize the lay modeling, estimated the best behavior for Cobb Avian 48 females, because while it takes more time to reach the level of putting constant (5.30 weeks) and maintain it for less time (2.4 weeks), they manage to put constant high (79.11%) level, considering that the largest number of eggs per bird (171.19 vs. 164.54 and 160.11 in Arbor Acres and Ross 208, respectively).展开更多
For certain applications, the paper proposes a LOD generation algorithm based on model feature, to measure the value of certain features as weight, and to just the geometrical characteristics and retains the full feat...For certain applications, the paper proposes a LOD generation algorithm based on model feature, to measure the value of certain features as weight, and to just the geometrical characteristics and retains the full feature in the simplified model. Algorithm is simple and intuitive, LOD models can be generated by a continuous smooth transition and meet the requirements of real-time display. Experimental results show the effectiveness of the algorithm. Algorithm is simple and quick, broad applicability, the improve simplified algorithm is very suitable for modulation texture operator, generating algorithm based on a lookup table to meet the model requirements for real-time display.展开更多
This study proposes a novel dual S-shaped logistic model for automatically quantifying the characteristic kinetic curves of breast lesions and for distinguishing malignant from benign breast tumors on dynamic contrast...This study proposes a novel dual S-shaped logistic model for automatically quantifying the characteristic kinetic curves of breast lesions and for distinguishing malignant from benign breast tumors on dynamic contrast enhanced (DCE) magnetic resonance (MR) images.D(,) is the diagnostic parameter derived from the logistic model.Significant differences were found in D(,) between the malignant benign groups.Fisher's Linear Discriminant analysis correctly classified more than 90% of the benign and malignant kinetic breast data using the derived diagnostic parameter (D(,)).Receiver operating characteristic curve analysis of the derived diagnostic parameter (D(,)) indicated high sensitivity and specificity to differentiate malignancy from benignancy.The dual S-shaped logistic model was effectively used to fit the kinetic curves of breast lesions in DCE-MR.Separation between benign and malignant breast lesions was achieved with sufficient accuracy by using the derived diagnostic parameter D(,) as the lesion's feature.The proposed method therefore has the potential for computer-aided diagnosis in breast tumors.展开更多
In recent years, bank credit business is booming with the increasing borrowing retention o~ China's listed companies, and debt financing has become the major approach among listed companies' financing strategies. As...In recent years, bank credit business is booming with the increasing borrowing retention o~ China's listed companies, and debt financing has become the major approach among listed companies' financing strategies. As a series of institutional arrangements about rights, responsibilities and benefits between different shareholders, corporate governance mechanism has a significant influence on the cost of debt financing. This paper employs variable coefficient panel data model to investigate the relationship of the listed company's debt financing costs and corporate governance mechanism in terms of structural characteristics and time series characteristics. The results show that optimizing the structure of both Board of Directors and Board of Supervisors, establishing a reasonable management incentive system and reducing the concentration of ownership properly can directly contribute to a lower company's debt financing costs. Meanwhile, property rights have an interactive influence on corporate governance from four aspects, which indirectly effect in company's debt financing costs.展开更多
基金Project (2011ZX05007-004) supported by the National Sciences and Technologies,ChinaProject (41502132) supported by the National Natural Science Foundation of China
文摘The lower Ordovician mid-assemblage Formations in the central Ordos Basin of China host prolific gas resources,and most hydrocarbon reserves are stored in naturally-fractured reservoirs.Thus,fracture pathway systems may have a significant impact on reservoir performance.This article focuses on the core-and laboratory-based characterization of fractures.Through the developmental degrees,extended scale,output state and filling characteristics of various types of fractures,the results show that there are three distinct fracture types:1)nearly vertical fractures,2)oblique fractures,and 3)horizontal fractures.Based on a systematic study of the characterization of reservoir space,the main geologic setting of natural gas accumulation and the regional tectonic background,type 1 is mainly driven by the tectonic formation mechanism,and type 3 and parts of low-angle fractures in type 2 are induced by the diagenetic formation mechanism.While recovered paleopressure for methane-rich aqueous inclusions trapped in fracture-filling cement indicates that the fracture opening and growth are consistent with gas maturation and charge and such high-angle fractures in type 2 are caused by the compound formation mechanism.The fractures to hydrocarbon accumulation may play a more significant role in improving the quality of reservoir porosity.Furthermore,connected fractures,dissolved pores and cavities together constitute the three-dimensional pore-cave-fracture network pathway systems,with faults serving as the dominant charge pathways of highly pressurized gas in the study area.Our results demonstrate that protracted growth of a pervasive fracture system is not only the consequence of various formation mechanisms but also intrinsic to quasi-continuous accumulation reservoirs.
文摘The objective of the present work is characterizing some parameters in the lay phase in the lines of heavy broilers breeder Cobb Avian 48, Arbor Acres Plus and Ross 208, reared under the same commercial conditions in the tropics. Monitored three batches of approximately 18,000 females each (one for each genetic type), from weeks 24 to 64, according to the conditions of handling and power described by the generic lines distribution companies. Although no differences were found for feed intake, Cobb Avian was presented a lower rate of feed conversion, being also that presented the highest percentage of implementation and production of incubables eggs, which meant that it was in line with the highest cumulative production of chickens by bird and week for tropical conditions studied. To adjust the lay data to a Gorssman model, in order to predict the parameters that characterize the lay modeling, estimated the best behavior for Cobb Avian 48 females, because while it takes more time to reach the level of putting constant (5.30 weeks) and maintain it for less time (2.4 weeks), they manage to put constant high (79.11%) level, considering that the largest number of eggs per bird (171.19 vs. 164.54 and 160.11 in Arbor Acres and Ross 208, respectively).
文摘For certain applications, the paper proposes a LOD generation algorithm based on model feature, to measure the value of certain features as weight, and to just the geometrical characteristics and retains the full feature in the simplified model. Algorithm is simple and intuitive, LOD models can be generated by a continuous smooth transition and meet the requirements of real-time display. Experimental results show the effectiveness of the algorithm. Algorithm is simple and quick, broad applicability, the improve simplified algorithm is very suitable for modulation texture operator, generating algorithm based on a lookup table to meet the model requirements for real-time display.
文摘This study proposes a novel dual S-shaped logistic model for automatically quantifying the characteristic kinetic curves of breast lesions and for distinguishing malignant from benign breast tumors on dynamic contrast enhanced (DCE) magnetic resonance (MR) images.D(,) is the diagnostic parameter derived from the logistic model.Significant differences were found in D(,) between the malignant benign groups.Fisher's Linear Discriminant analysis correctly classified more than 90% of the benign and malignant kinetic breast data using the derived diagnostic parameter (D(,)).Receiver operating characteristic curve analysis of the derived diagnostic parameter (D(,)) indicated high sensitivity and specificity to differentiate malignancy from benignancy.The dual S-shaped logistic model was effectively used to fit the kinetic curves of breast lesions in DCE-MR.Separation between benign and malignant breast lesions was achieved with sufficient accuracy by using the derived diagnostic parameter D(,) as the lesion's feature.The proposed method therefore has the potential for computer-aided diagnosis in breast tumors.
基金This research is supported by the National Natural Science Foundation of China under Grant No.71003115Collaborative Innovation CenterResearch Innovation Team Supporting Plan of the Central University of Finance and Economics
文摘In recent years, bank credit business is booming with the increasing borrowing retention o~ China's listed companies, and debt financing has become the major approach among listed companies' financing strategies. As a series of institutional arrangements about rights, responsibilities and benefits between different shareholders, corporate governance mechanism has a significant influence on the cost of debt financing. This paper employs variable coefficient panel data model to investigate the relationship of the listed company's debt financing costs and corporate governance mechanism in terms of structural characteristics and time series characteristics. The results show that optimizing the structure of both Board of Directors and Board of Supervisors, establishing a reasonable management incentive system and reducing the concentration of ownership properly can directly contribute to a lower company's debt financing costs. Meanwhile, property rights have an interactive influence on corporate governance from four aspects, which indirectly effect in company's debt financing costs.