Inferring the experimental variogram used in geostatistics commonly relies on the method-of-moments approach.Ideally,the available data-set used for calculating the experimental variogram should be drawn from a regula...Inferring the experimental variogram used in geostatistics commonly relies on the method-of-moments approach.Ideally,the available data-set used for calculating the experimental variogram should be drawn from a regular pattern.However,in practice the available data-set is typically sampled over a sparse pattern at irregularly spaced locations.Hence,some binning of the variogram cloud is required to obtain fair estimates of the experimental variogram.Grouping of the variogram data pairs as a result of conventional binning depends on parameters such as the main anisotropic directions and a regular definition of the lag vectors.These parameters are not based on the configuration of the variogram data pairs in the variogram cloud but on a segment of it that is arbitrarily predefined.Therefore,the conventional experimental variogram estimation approach is biased because of the strict configuration of the bins over the variogram cloud.In this paper,a new method of estimating experimental variograms is proposed.Lag vectors and their tolerances are decided in the proposed method from information in the variogram cloud：they are not influenced by any predefined directions.The proposed methodology is a well-founded,practicable and easy-to-automate approach for experimental variogram calculation using an irregularly sampled data-set.Comparison of results from the new method to those from the traditional approach is very encouraging.展开更多
Oxidative desulfurization (ODS) of Azeri crude oil was studied under the electric field.By means of orthogonal experiments,the optimum conditions for desulfurization of crude oil were identified,while the effect of ox...Oxidative desulfurization (ODS) of Azeri crude oil was studied under the electric field.By means of orthogonal experiments,the optimum conditions for desulfurization of crude oil were identified,while the effect of oxidative desulfurization under the electric field was compared with that of the single oxidative desulfurization method.The test results showed that the desulfurization reaction taking place under the electric field would be better than the traditional method.The desulfurization rate of crude oil could reach up to 77.06% at 115 ℃ at a distilled water amount of 10 m%,a desulfurizer dosage of 200 μg/g,and a demulsifier dosage of 50 μg/g.展开更多
objective： to study the problem oriented （PBL） teaching method application in surgery theory teaching effect. Methods： according to the student id number of single and double the surgical theory study stage of the...objective： to study the problem oriented （PBL） teaching method application in surgery theory teaching effect. Methods： according to the student id number of single and double the surgical theory study stage of the 160 cases of medical students divided into two groups, the number into the control group （80 cases）, double number into the experimental group （80 cases）, traditional teaching method and PBL teaching method, respectively with the method of questionnaire survey to evaluate the two teaching methods. Results： after the introduction of PBL method in the experimental teaching, the students＇ classroom situation, knowledge situation, learning efficiency index score significantly higher than the control group, and the ability training all indicators were significantly higher than that of control group （P 〈 0.05）. Conclusion： the introduction of PBL in surgery theory teaching method, the feasibility of high, can provide a good decision for surgical theory teaching.展开更多
In this research, it used advanced oxidation processes for the recovery, detoxification and mineralization of wastewater mainly contaminated by antibiotics （ciprofloxacin）. These processes can be used alone or in co...In this research, it used advanced oxidation processes for the recovery, detoxification and mineralization of wastewater mainly contaminated by antibiotics （ciprofloxacin）. These processes can be used alone or in combination with each other or by complementing traditional methods, even allowing the disinfection of bacterial and viral inactivation. With the use of experimental systems UV/H202/O3, UV/H202, it can achieve total mineralization of the compound. Ciprofloxacin solutions used at 50, 100, 200, 300, 400 and 500 ppm, degraded to 100% of antibiotics and by a microbiological method show that the loss of biological activity is inversely proportional to the time of irradiation.展开更多
An empirical study is conducted to examine the effect of constructing sense relations in vocabulary teaching. Fifty subjects are divided into two groups： the controlled group which was taught with traditional method,...An empirical study is conducted to examine the effect of constructing sense relations in vocabulary teaching. Fifty subjects are divided into two groups： the controlled group which was taught with traditional method, and the experimental group to which sense relation strategy was applied in vocabulary instruction. At the end of the experiment instruction, a test （depth of vocabulary knowledge measure） was given to examine the teaching effects of the two vocabulary teaching strategies. The target words in the tests were selected from the word list that had been taught during the experiment time. A delayed vocabulary posttest was given to the subjects two weeks after examining the long-term retention effect. The third test was administered with different targets words which were selected from a different intensive reading material which wass new to the subjects. The experiment proves that constructing sense relations in vocabulary teaching could produce satisfactory results by enhancing students＇ lexical capacity and long-term retention.展开更多
The seismic characteristics of four typical mortise-tenon joints of Chinese southern traditional timber frame buildings were researched, including Yanwei mortise-tenon joint （including dropping Yanwei mortise-tenon j...The seismic characteristics of four typical mortise-tenon joints of Chinese southern traditional timber frame buildings were researched, including Yanwei mortise-tenon joint （including dropping Yanwei mortise-tenon joint）, Shizigutou mortise-tenon joint, Ban mortise-tenon joint and Mantou mortise-tenon joint. Experiments on thirteen specimens were carried out. Failure modes, hysteresis curves, skeleton curves and rotational stiffness were studied. The results provided a theoretical basis for seismic research, protection and maintenance of Chinese southern traditional timber flame buildings.展开更多
In wireless sensor networks （WSNs）, group key distribution is the core of secure communications since sensor nodes usually form groups and cooperate with each other in sensing data collection and in-network processi...In wireless sensor networks （WSNs）, group key distribution is the core of secure communications since sensor nodes usually form groups and cooperate with each other in sensing data collection and in-network processing. In this paper, we present a scalable authenticated scheme for group key distribution based on a combinatorial exclusion basis system （EBS） for efficiency and one-way hash chains for authentication. The proposed scheme guarantees a lightweight authenticated group key updating procedure and is efficient in terms of storage, communication and computation overheads.展开更多
文摘Inferring the experimental variogram used in geostatistics commonly relies on the method-of-moments approach.Ideally,the available data-set used for calculating the experimental variogram should be drawn from a regular pattern.However,in practice the available data-set is typically sampled over a sparse pattern at irregularly spaced locations.Hence,some binning of the variogram cloud is required to obtain fair estimates of the experimental variogram.Grouping of the variogram data pairs as a result of conventional binning depends on parameters such as the main anisotropic directions and a regular definition of the lag vectors.These parameters are not based on the configuration of the variogram data pairs in the variogram cloud but on a segment of it that is arbitrarily predefined.Therefore,the conventional experimental variogram estimation approach is biased because of the strict configuration of the bins over the variogram cloud.In this paper,a new method of estimating experimental variograms is proposed.Lag vectors and their tolerances are decided in the proposed method from information in the variogram cloud：they are not influenced by any predefined directions.The proposed methodology is a well-founded,practicable and easy-to-automate approach for experimental variogram calculation using an irregularly sampled data-set.Comparison of results from the new method to those from the traditional approach is very encouraging.
基金financial supports from the Science and Technology Office of Liaoning Province (Project number:2008403001)the Liaoning Provincial Office of Education for Innovation Team (Project number:2009T002)
文摘Oxidative desulfurization (ODS) of Azeri crude oil was studied under the electric field.By means of orthogonal experiments,the optimum conditions for desulfurization of crude oil were identified,while the effect of oxidative desulfurization under the electric field was compared with that of the single oxidative desulfurization method.The test results showed that the desulfurization reaction taking place under the electric field would be better than the traditional method.The desulfurization rate of crude oil could reach up to 77.06% at 115 ℃ at a distilled water amount of 10 m%,a desulfurizer dosage of 200 μg/g,and a demulsifier dosage of 50 μg/g.
文摘objective： to study the problem oriented （PBL） teaching method application in surgery theory teaching effect. Methods： according to the student id number of single and double the surgical theory study stage of the 160 cases of medical students divided into two groups, the number into the control group （80 cases）, double number into the experimental group （80 cases）, traditional teaching method and PBL teaching method, respectively with the method of questionnaire survey to evaluate the two teaching methods. Results： after the introduction of PBL method in the experimental teaching, the students＇ classroom situation, knowledge situation, learning efficiency index score significantly higher than the control group, and the ability training all indicators were significantly higher than that of control group （P 〈 0.05）. Conclusion： the introduction of PBL in surgery theory teaching method, the feasibility of high, can provide a good decision for surgical theory teaching.
文摘In this research, it used advanced oxidation processes for the recovery, detoxification and mineralization of wastewater mainly contaminated by antibiotics （ciprofloxacin）. These processes can be used alone or in combination with each other or by complementing traditional methods, even allowing the disinfection of bacterial and viral inactivation. With the use of experimental systems UV/H202/O3, UV/H202, it can achieve total mineralization of the compound. Ciprofloxacin solutions used at 50, 100, 200, 300, 400 and 500 ppm, degraded to 100% of antibiotics and by a microbiological method show that the loss of biological activity is inversely proportional to the time of irradiation.
文摘An empirical study is conducted to examine the effect of constructing sense relations in vocabulary teaching. Fifty subjects are divided into two groups： the controlled group which was taught with traditional method, and the experimental group to which sense relation strategy was applied in vocabulary instruction. At the end of the experiment instruction, a test （depth of vocabulary knowledge measure） was given to examine the teaching effects of the two vocabulary teaching strategies. The target words in the tests were selected from the word list that had been taught during the experiment time. A delayed vocabulary posttest was given to the subjects two weeks after examining the long-term retention effect. The third test was administered with different targets words which were selected from a different intensive reading material which wass new to the subjects. The experiment proves that constructing sense relations in vocabulary teaching could produce satisfactory results by enhancing students＇ lexical capacity and long-term retention.
基金supported by the National Natural Science Foundation of China(Grant No.51008059)China Postdoctoral Science Special Foundation(Grant No.201003543)
文摘The seismic characteristics of four typical mortise-tenon joints of Chinese southern traditional timber frame buildings were researched, including Yanwei mortise-tenon joint （including dropping Yanwei mortise-tenon joint）, Shizigutou mortise-tenon joint, Ban mortise-tenon joint and Mantou mortise-tenon joint. Experiments on thirteen specimens were carried out. Failure modes, hysteresis curves, skeleton curves and rotational stiffness were studied. The results provided a theoretical basis for seismic research, protection and maintenance of Chinese southern traditional timber flame buildings.
基金the National High Technology Research and Development Program (863) of China (Nos. 2006AA01Z436, 2007AA01Z455, and2007AA01Z473)
文摘In wireless sensor networks （WSNs）, group key distribution is the core of secure communications since sensor nodes usually form groups and cooperate with each other in sensing data collection and in-network processing. In this paper, we present a scalable authenticated scheme for group key distribution based on a combinatorial exclusion basis system （EBS） for efficiency and one-way hash chains for authentication. The proposed scheme guarantees a lightweight authenticated group key updating procedure and is efficient in terms of storage, communication and computation overheads.
