Daniau Village in Daniau Creek Watershed, Taitung County, Taiwan, sustained damages from landslides and mudflows during Typhoon Morakot in 2009. The purpose of this study is to adopt the FLO-2D numerical model recogni...Daniau Village in Daniau Creek Watershed, Taitung County, Taiwan, sustained damages from landslides and mudflows during Typhoon Morakot in 2009. The purpose of this study is to adopt the FLO-2D numerical model recognized by Federal Emergency Management Agency （FEMA） to simulate the mudflow, and the Daniau Village was used as a case study, along with rainfall and digital terrain data for this simulation. On the basis of sediment yields, the residual sediment volume in the landslide area was determined to be 33,276 ma by comparison of digital elevation models （DEMs） and by using the universal soil loss equation （USLE）. In addition, this study performed a hydrological frequency analysis of rainfall to estimate the flow discharge as conditions of the simulation. Results of disaster surveys were collected to compare with outputs of the numerical model. Results of the simulation conducted with FLO- 2D indicated that if the countermeasure was not destroyed, the drainage work would function without overflow. This study aimed to review the effectiveness of eountermeasure on the basis of simulation results obtained by using the model to provide references for future disaster prevention and resident evacuation plans.展开更多
The gear transmission system has been widely applied in mechanical systems, and many high-performance applications of these systems require low weight. With the aid of establishing the optimization model of the gear t...The gear transmission system has been widely applied in mechanical systems, and many high-performance applications of these systems require low weight. With the aid of establishing the optimization model of the gear transmission system that consists of an objective function and some constraints （for example, the bending stress, the contact stress, the torsional strength, etc.）, the optimal weight design of the gear transmission system can be transformed into the optimization problem for the objective function under the constraints. Moreover, both the shaft and the gear of the gear transmission system are considered simultaneously in our design. The hybrid Taguchi-genetic algorithm （HTGA） is employed to find the optimal design variables and the optimal weight of the system. An illustrated example for the single spur gear reducer is given to show that the optimal weight design problem can be successfully solved using the proposed design scheme. It also proves the high efficiency and feasibility of the algorithm in the gear design.展开更多
BACKGROUND Minimally invasive surgery had been tailored to individual cases of gastric subepithelial tumors(SETs)after comparing the clinical outcomes of endoscopic resection(ER),laparoscopic resection(LR),and hybrid ...BACKGROUND Minimally invasive surgery had been tailored to individual cases of gastric subepithelial tumors(SETs)after comparing the clinical outcomes of endoscopic resection(ER),laparoscopic resection(LR),and hybrid methods.AIM To study the use of Goldilocks principle to determine the best form of minimally invasive surgery for gastric SETs.METHODS In this retrospective study,194 patients of gastric SETs with high probability of surgical intervention were included.All patients underwent tumor resection in the operating theater between January 2013 and December 2021.The patients were divided into two groups,ER or LR,according to the tumor characteristics and the initial intent of intervention.Few patients in the ER group required further backup laparoscopic surgery after an incomplete ER.The patients who had converted open surgery were excluded.A logistic regression model was used to assess the associations between patient characteristics and the likelihood of a treatment strategy.The area under the curve was used to assess the discriminative ability of tumor size and Youden’s index to determine the optimal cut-off tumor size.RESULTS One-hundred ninety-four patients(100 in the ER group and 94 in the LR group)underwent tumor resection in the operating theater.In the ER group,27 patients required backup laparoscopic surgery after an incomplete ER.The patients in the ER group had small tumor sizes and shorter procedure durations while the patients in the LR group had large tumor sizes,exophytic growth,malignancy,and tumors that were more often located in the middle or lower third of the stomach.Both groups had similar durations of hospital stays and a similar rate of major postoperative complications.The patients in the ER group who underwent backup surgery required longer procedures(56.4 min)and prolonged stays(2 d)compared to the patients in the LR group without the increased rate of major postoperative complications.The optimal cut-off point for the tumor size for laparoscopic surgery was 2.15 cm.CONCLUSION Mul展开更多
This present study develops a 2-D numerical scheme to simulate the velocity and depth on the actual terrain by using shallow water equations. The computational approach uses the HLL scheme as a basic building block, t...This present study develops a 2-D numerical scheme to simulate the velocity and depth on the actual terrain by using shallow water equations. The computational approach uses the HLL scheme as a basic building block, treats the bottom slope by lateralizing the momentum flux, then refines the scheme using the Strang splitting to deal with the frictional source term. Besides, a decoupled algorithm is also adopted to compute the aggradation and degradation of bed-level elevation by using the Manning-Strickler formula and Exner’s relationship. The main purpose is to set up the window interface of 2-D numerical model and increase the realization of engineers on these characteristics of hydraulic treatment and maintenance.展开更多
The generalized maximum principle of Lou and Ni is extended from elliptic equations to parabolic equations. By this result, one can show that the system of fugal mycelia has a global attractor if the diffusion coeffic...The generalized maximum principle of Lou and Ni is extended from elliptic equations to parabolic equations. By this result, one can show that the system of fugal mycelia has a global attractor if the diffusion coefficient D = 0 and the solution blows up ifD= 0. The method of linearization is applied to derive the existence of Hopfs bifurcation which is the signature of instability of Turing system. The increasing of the size of the attractor and the existence of Hopf＇ s bifurcation indicate that there is a threshold that initiates the instability.展开更多
In recent years, global warming has gradually become obvious, thus created the climate change. Typhoon Morakot attacked Taiwan and brought heavy rainfall in August, 2009. In mountainous areas including Central and Sou...In recent years, global warming has gradually become obvious, thus created the climate change. Typhoon Morakot attacked Taiwan and brought heavy rainfall in August, 2009. In mountainous areas including Central and South Taiwan, the flood and debris flow disasters were induced by the typhoon. In this study, Changhua City is selected as the research region and the Delphi method is employed to interview experts and establish comprehensive evaluation criteria for assessing the evacuation plan on disaster areas. The concept is to combine the landslide potential analysis by geographic information systems with the flood or debris flow maps into the potential hazard map. Meanwhile, analytic hierarchy method (AHP) is comprehensively carried on the expert questionnaire survey for the potential hazard map of the compound disaster states. It should be useful for the local government and native people in the future.展开更多
American English is predominantly prescribed as the primary English learning model at every educational level in Taiwan and limited attention is paid to other accents of English. It is therefore the intention of this ...American English is predominantly prescribed as the primary English learning model at every educational level in Taiwan and limited attention is paid to other accents of English. It is therefore the intention of this paper to investigate whether Taiwan Residents EFL learners have difficulties understanding British English after years of instruction in American English, and to identify differences between learners＇ attitudes towards these two varieties of English. EFL learners from two universities were randomly assigned to American and British English groups and required to listen to short texts recorded with either American or British accent. An independent simple t-test showed that no significant differences were found in listening comprehension scores, but responses on questionnaires revealed significant differences in attitudes towards American and British English. The influence of long-term instruction in American English was evidenced. Based on these findings, suggestions are provided for English language teaching in Taiwan and implications are drawn for the concept of English as an International Language （ELL）, that in order to pursue successful international communication with people of various native languages, EFL learners need to experience various accents of English.展开更多
Over the past years studies have pointed out that 5 to 6-year-old children are able to use complex sentences in their oral language. Complex sentences may contain different kinds of subordinate or embedded clauses suc...Over the past years studies have pointed out that 5 to 6-year-old children are able to use complex sentences in their oral language. Complex sentences may contain different kinds of subordinate or embedded clauses such as noun clauses, adverbial clauses or relative clauses, which again may be respectively divided into smaller units in terms of function and form. It is interesting therefore to investigate how subordinate clauses are applied by 5 to 6-year-old Chinese-speaking children. The present study, which is based on the verbal responses of 10 Taiwan Residents upper-level kindergarteners aged from 5.5 to 6.5 years, aims to investigate specifically how two kinds of subordinate clauses, namely noun and relative clauses, are applied in children＇s speech. Data analysis shows that of the 4 kinds of noun clauses, only object noun clauses are applied by the child-respondents. With their much more complex syntactic constructions, noun clauses, compliment noun clauses and appositive noun clauses do not appear in their oral responses at all. Concerning relative clauses and their derived participle phrases, none of the respondents apply any V＋的＋N construction in their verbal responses. The VO＋的＋N construction is used by 7 respondents, while the S＋的＋N construction is used by 5 respondents.展开更多
基金supported in part by the National Science Council (NSC 97-2313-B-270-001-MY3) and Taitung Branch,Soil and Water Conservation Bureau, Council of Agriculture,Taiwan
文摘Daniau Village in Daniau Creek Watershed, Taitung County, Taiwan, sustained damages from landslides and mudflows during Typhoon Morakot in 2009. The purpose of this study is to adopt the FLO-2D numerical model recognized by Federal Emergency Management Agency （FEMA） to simulate the mudflow, and the Daniau Village was used as a case study, along with rainfall and digital terrain data for this simulation. On the basis of sediment yields, the residual sediment volume in the landslide area was determined to be 33,276 ma by comparison of digital elevation models （DEMs） and by using the universal soil loss equation （USLE）. In addition, this study performed a hydrological frequency analysis of rainfall to estimate the flow discharge as conditions of the simulation. Results of disaster surveys were collected to compare with outputs of the numerical model. Results of the simulation conducted with FLO- 2D indicated that if the countermeasure was not destroyed, the drainage work would function without overflow. This study aimed to review the effectiveness of eountermeasure on the basis of simulation results obtained by using the model to provide references for future disaster prevention and resident evacuation plans.
基金Supported by the Fundamental Research Funds for the Central Universities (20102080201000085)the National Natural Science Foundation of China (50875189)
文摘The gear transmission system has been widely applied in mechanical systems, and many high-performance applications of these systems require low weight. With the aid of establishing the optimization model of the gear transmission system that consists of an objective function and some constraints （for example, the bending stress, the contact stress, the torsional strength, etc.）, the optimal weight design of the gear transmission system can be transformed into the optimization problem for the objective function under the constraints. Moreover, both the shaft and the gear of the gear transmission system are considered simultaneously in our design. The hybrid Taguchi-genetic algorithm （HTGA） is employed to find the optimal design variables and the optimal weight of the system. An illustrated example for the single spur gear reducer is given to show that the optimal weight design problem can be successfully solved using the proposed design scheme. It also proves the high efficiency and feasibility of the algorithm in the gear design.
基金The study was approved by the Institutional Review Board of Changhua Christian Hospital(approval No.220117).
文摘BACKGROUND Minimally invasive surgery had been tailored to individual cases of gastric subepithelial tumors(SETs)after comparing the clinical outcomes of endoscopic resection(ER),laparoscopic resection(LR),and hybrid methods.AIM To study the use of Goldilocks principle to determine the best form of minimally invasive surgery for gastric SETs.METHODS In this retrospective study,194 patients of gastric SETs with high probability of surgical intervention were included.All patients underwent tumor resection in the operating theater between January 2013 and December 2021.The patients were divided into two groups,ER or LR,according to the tumor characteristics and the initial intent of intervention.Few patients in the ER group required further backup laparoscopic surgery after an incomplete ER.The patients who had converted open surgery were excluded.A logistic regression model was used to assess the associations between patient characteristics and the likelihood of a treatment strategy.The area under the curve was used to assess the discriminative ability of tumor size and Youden’s index to determine the optimal cut-off tumor size.RESULTS One-hundred ninety-four patients(100 in the ER group and 94 in the LR group)underwent tumor resection in the operating theater.In the ER group,27 patients required backup laparoscopic surgery after an incomplete ER.The patients in the ER group had small tumor sizes and shorter procedure durations while the patients in the LR group had large tumor sizes,exophytic growth,malignancy,and tumors that were more often located in the middle or lower third of the stomach.Both groups had similar durations of hospital stays and a similar rate of major postoperative complications.The patients in the ER group who underwent backup surgery required longer procedures(56.4 min)and prolonged stays(2 d)compared to the patients in the LR group without the increased rate of major postoperative complications.The optimal cut-off point for the tumor size for laparoscopic surgery was 2.15 cm.CONCLUSION Mul
文摘This present study develops a 2-D numerical scheme to simulate the velocity and depth on the actual terrain by using shallow water equations. The computational approach uses the HLL scheme as a basic building block, treats the bottom slope by lateralizing the momentum flux, then refines the scheme using the Strang splitting to deal with the frictional source term. Besides, a decoupled algorithm is also adopted to compute the aggradation and degradation of bed-level elevation by using the Manning-Strickler formula and Exner’s relationship. The main purpose is to set up the window interface of 2-D numerical model and increase the realization of engineers on these characteristics of hydraulic treatment and maintenance.
文摘The generalized maximum principle of Lou and Ni is extended from elliptic equations to parabolic equations. By this result, one can show that the system of fugal mycelia has a global attractor if the diffusion coefficient D = 0 and the solution blows up ifD= 0. The method of linearization is applied to derive the existence of Hopfs bifurcation which is the signature of instability of Turing system. The increasing of the size of the attractor and the existence of Hopf＇ s bifurcation indicate that there is a threshold that initiates the instability.
文摘In recent years, global warming has gradually become obvious, thus created the climate change. Typhoon Morakot attacked Taiwan and brought heavy rainfall in August, 2009. In mountainous areas including Central and South Taiwan, the flood and debris flow disasters were induced by the typhoon. In this study, Changhua City is selected as the research region and the Delphi method is employed to interview experts and establish comprehensive evaluation criteria for assessing the evacuation plan on disaster areas. The concept is to combine the landslide potential analysis by geographic information systems with the flood or debris flow maps into the potential hazard map. Meanwhile, analytic hierarchy method (AHP) is comprehensively carried on the expert questionnaire survey for the potential hazard map of the compound disaster states. It should be useful for the local government and native people in the future.
文摘American English is predominantly prescribed as the primary English learning model at every educational level in Taiwan and limited attention is paid to other accents of English. It is therefore the intention of this paper to investigate whether Taiwan Residents EFL learners have difficulties understanding British English after years of instruction in American English, and to identify differences between learners＇ attitudes towards these two varieties of English. EFL learners from two universities were randomly assigned to American and British English groups and required to listen to short texts recorded with either American or British accent. An independent simple t-test showed that no significant differences were found in listening comprehension scores, but responses on questionnaires revealed significant differences in attitudes towards American and British English. The influence of long-term instruction in American English was evidenced. Based on these findings, suggestions are provided for English language teaching in Taiwan and implications are drawn for the concept of English as an International Language （ELL）, that in order to pursue successful international communication with people of various native languages, EFL learners need to experience various accents of English.
文摘Over the past years studies have pointed out that 5 to 6-year-old children are able to use complex sentences in their oral language. Complex sentences may contain different kinds of subordinate or embedded clauses such as noun clauses, adverbial clauses or relative clauses, which again may be respectively divided into smaller units in terms of function and form. It is interesting therefore to investigate how subordinate clauses are applied by 5 to 6-year-old Chinese-speaking children. The present study, which is based on the verbal responses of 10 Taiwan Residents upper-level kindergarteners aged from 5.5 to 6.5 years, aims to investigate specifically how two kinds of subordinate clauses, namely noun and relative clauses, are applied in children＇s speech. Data analysis shows that of the 4 kinds of noun clauses, only object noun clauses are applied by the child-respondents. With their much more complex syntactic constructions, noun clauses, compliment noun clauses and appositive noun clauses do not appear in their oral responses at all. Concerning relative clauses and their derived participle phrases, none of the respondents apply any V＋的＋N construction in their verbal responses. The VO＋的＋N construction is used by 7 respondents, while the S＋的＋N construction is used by 5 respondents.
