The inbound and outbound tasks for valuable imported ship outfitting items are operated by multiple automated guided vehicles(AGVs)simultaneously in the outfitting warehouse.Given the efficiency mismatch between trans...The inbound and outbound tasks for valuable imported ship outfitting items are operated by multiple automated guided vehicles(AGVs)simultaneously in the outfitting warehouse.Given the efficiency mismatch between transportation equipment and the lack of effective scheduling of AGVs,the objective of the studied scheduling problem is to minimize the total travel time cost of vehicles.A multi-AGV task scheduling model based on time window is established considering the loading constraints of AGVs and cooperation time window constraints of stackers.According to the transportation characteristics in the outfitting warehouse,this study pro-poses a conflict detection method for heavy forklift AGVs,and correspondingly defines a conflict penalty function.Furthermore,to comprehensively optimize travel time cost and conflict penalty,a hybrid genetic neighborhood search algorithm(GA-ANS)is proposed.Five neighborhood structures are designed,and adaptive selection opera-tors are introduced to enhance the ability of global search and local chemotaxis.Numerical experiments show that the proposed GA-ANS algorithm can effectively solve the problem even when the scale of the problem increases and the effectiveness of the vehicle conflict penalty strategy is analyzed.展开更多
In real-world scenarios,dual-view X-ray machines have outnumbered single-view X-ray machines due to their ability to provide comprehensive internal information about the baggage,which is important for identifying proh...In real-world scenarios,dual-view X-ray machines have outnumbered single-view X-ray machines due to their ability to provide comprehensive internal information about the baggage,which is important for identifying prohibited items that are not visible in one view due to rotation or overlap.However,existing work still focuses mainly on single-view,and the limited dual-viewbasedwork only performs simple information fusion at the feature or decision level and lacks effective utilization of the complementary information hidden in dual view.To this end,this paper proposes an end-to-end dual-view prohibited item detection method,the core of which is an adaptive material-aware coordinate-aligned attention module(MACA)and an adaptive adjustment strategy(AAS).Specifically,we observe that in X-ray images,the material information of an object can be represented by color and texture features,and remains consistent across views,even under complex backgrounds.Therefore,our MACA first integrates the material information of the prohibited items in each view and then smoothly transfers these clearmaterial clues along the shared axis to the corresponding locations in the other view to enhance the feature representation of the blurred prohibited items in the other view.In addition,AAS can autonomously adjust the importance of the two views during feature learning to make joint optimizationmore stable and effective.Experiments on the DvXray dataset demonstrate that the proposed MACA and AAS can be plug-and-played into various detectors,such as Faster Region-based Convolutional Neural Network(Faster R-CNN)and Fully Convolutional One-Stage Object Detector(FCOS),and bring consistent performance gains.The entire framework performs favorably against state-of-the-art methods,especially on small-sized prohibited items,highlighting its potential application in reality.展开更多
Loneliness is a complex and usually unpleasant emotional response to isolation,which has been considered the latest global health epidemic exacerbated by the coronavirus disease 2019 pandemic,affecting nearly twothird...Loneliness is a complex and usually unpleasant emotional response to isolation,which has been considered the latest global health epidemic exacerbated by the coronavirus disease 2019 pandemic,affecting nearly twothirds of older adults.Some profound health implications carried by loneliness include depression,cognitive impairment,hypertension and frailty.Across the world,there is no consensus definition of loneliness,and its measure is based on the phenomenological perspective of the individual.The 20-item University of California Los Angeles Loneliness Scale version 3(UCLA-20)is the most common measure.This scale demonstrates acceptable psychometric properties but is too long and complex for a phone interview.This paper addresses the increasing need to shorten this scale by adopting classical item response theory and network psychometrics to advance scale development.Through an item reduction analysis,we trimmed the original scale into an effective short form,which is as valid as the original one.With respondents’time at a premium in most research nowadays,this shortform scale is an efficient and practical alternative to the original UCLA-20.展开更多
In this paper,we focus on the detection of prohibited items with small size,and establish an automatic detection model based on feature fusion single shot multibox detector(FSSD)architecture.Two modifications are carr...In this paper,we focus on the detection of prohibited items with small size,and establish an automatic detection model based on feature fusion single shot multibox detector(FSSD)architecture.Two modifications are carried out to improve the detection accuracy.Firstly,the semantic enrichment module(SEM)with dilated convolution is applied to extract the low level feature with strong semantic information.Secondly,a residual module(Res)with residual blocks is added in the multibox detection architecture in order to extract more adequate features for target detection.The simulation results have demonstrated a better performance of the proposed detection model for prohibited items with small size compared with the state-of-the-arts.展开更多
In recent times, mathematical models have been developed to describe various scenarios obtainable in the management of inventories. These models usually have as objective the minimizing of inventory costs. In this res...In recent times, mathematical models have been developed to describe various scenarios obtainable in the management of inventories. These models usually have as objective the minimizing of inventory costs. In this research work we propose a mathematical model of an inventory system with time-dependent three-parameter Weibull deterioration and a stochastic type demand in the form of a negative exponential distribution. Explicit expressions for the optimal values of the decision variables are obtained. Numerical examples are provided to illustrate the theoretical development.展开更多
In intercontinental trade and economics goods are bought from a global supplier.On occasion,the expected lot may include a fraction of defective items.These imperfect items still have worth and can be sold to customer...In intercontinental trade and economics goods are bought from a global supplier.On occasion,the expected lot may include a fraction of defective items.These imperfect items still have worth and can be sold to customers after repair.It is cost-effective and sustainable to rework such items in nearby repair workshops rather than return them.The reworked items can be returned from the workshop to the buyer when shortages are equal to the quantity of imperfect items.In the meantime,the supplier correspondingly deals a multi-period delay-in-payments strategy with purchaser.The entire profit has been maximized with paybacks for interim financing.This study aims to develop a synergic inventory model to get the most profit by making an allowance for reworking,multi-period delay-in-payments policy,and shortages.The findings of the proposed model augment inventory management performance by monitoring cycle time as well as fraction of phase with optimistic inventory for a supply chain.The results demonstrate that profit is smaller if the permitted period given by supplier to buyer is equal to or greater than the cycle time,and profit is greater if the permitted period is smaller than the cycle time.The algebraic method is engaged to make a closed system optimum solution.The mathematical experiment of this study is constructed to provide management insights and tangible practices.展开更多
Microwave fracturing of rocks before mechanical breakage could improve the performance of mechanical excavators and reduce environmental impacts.Previous research focused on the microwave fracturing of intact rock blo...Microwave fracturing of rocks before mechanical breakage could improve the performance of mechanical excavators and reduce environmental impacts.Previous research focused on the microwave fracturing of intact rock blocks.By using an open-ended antenna,this paper investigates the effect of pre-existing joints on the microwave fracturing of the Singapore Bukit Timah granite blocks.The results show that the specimens are weakened in the manners of cracking,spalling,melting,or a combination of them.The crack number and the total crack length produced by microwave treatment of jointed rock blocks are slightly smaller than those in the intact rock blocks.The interaction between joints and microwave-induced cracks can be summarized into the following four patterns:(1)microwave-induced cracks become arrested so that the crack propagation is terminated;(2)microwave-induced cracks penetrate the joints and continue to propagate;(3)microwave-induced cracks become deflected along the joints;and(4)microwave-induced cracks propagate forward following the joints.The smaller the approach angle between the microwave-induced crack and the preexisting joint is,the more microwave-induced cracks tend to be arrested at the joint.Increasing the approach angle between the microwave-induced crack and the joint can increase the chance of microwave-induced crack penetrating the joint.The results also show that the smaller the distance is between the microwave radiation point and the joint,the easier it is for microwave-induced cracks to penetrate the joints;otherwise,the microwave-induced crack is more likely to be arrested at the pre-existing joint.展开更多
The article deals with an economic order quantity (EOQ) inventory model for deteriorating items in which the supplier provides the purchaser a permissible delay in payment. This is so when deterioration of units in th...The article deals with an economic order quantity (EOQ) inventory model for deteriorating items in which the supplier provides the purchaser a permissible delay in payment. This is so when deterioration of units in the inventory is subject to constant deterioration rate, demand rate is quadratic function of time and salvage value is associated with the deteriorated units. Shortages in the system are not allowed to occur. A mathematical formulation is developed when the supplier offers a permissible delay period to the customers under two circumstances: 1) when delay period is less than the cycle of time;and 2) when delay period is greater than the cycle of time. The method is suitable for the items like state-of-the-art aircrafts, super computers, laptops, android mobiles, seasonal items and machines and their spare parts. A solution procedure algorithm is given for finding the optimal order quantity which minimizes the total cost of an inventory system. The article includes numerical examples to support the effectiveness of the developed model. Finally, sensitivity analysis on some parameters on optimal solution is provided.展开更多
The international financial reporting standard for cash flow statement （IAS 7） provides options for the classification of certain cash flow items （arbitrary items）. Therefore, business firms may classify the arbit...The international financial reporting standard for cash flow statement （IAS 7） provides options for the classification of certain cash flow items （arbitrary items）. Therefore, business firms may classify the arbitrary items using the option that would maximize their own interest. This reduces the comparability of financial statements amongst business firms. This study aims to investigate the factors explaining management preferences in the selection of financial reporting practices on the arbitrary cash flow items. It concludes that managers tend to magnify the CFO reported in order to maximize the shareholders＇ wealth, which in turn would maximize their compensation. Managers of business firms with a relatively smaller size of CFO tend to classify interest paid and dividends paid as non-CFO in order to magnify their CFO. They also tend to classify interest received as CFO in order to inflate their relatively smaller size of CFO up to expectation. Similarly, managers of business firms with a relative larger size of dividends paid would classify the dividends paid outside CFO.展开更多
The 19th National Congress of the Communist Party of China is a meeting of great importance held during the decisivestage of building a moderately prosperous society in all respects.As a window to know about the lates...The 19th National Congress of the Communist Party of China is a meeting of great importance held during the decisivestage of building a moderately prosperous society in all respects.As a window to know about the latest changes of China,it is au-thoritative and of much value to study.As time goes by,there emerge more lexical items with Chinese characteristics.This articlestudies Chinese-English translation skills of lexical items with Chinese Characteristics in the Report on the 19th National Congressof the CPC.First,it classifies these lexical items into several kinds including those related with economy,politics,culture,peo-ple’s wellbeing and other lexical items,and then studies them respectively.展开更多
The classical EPQ model has been used for a long ti me and is widely accepted and implemented. Nevertheless, the analysis for finding an economic lot size has based on a number of unrealistic assumptions. A common unr...The classical EPQ model has been used for a long ti me and is widely accepted and implemented. Nevertheless, the analysis for finding an economic lot size has based on a number of unrealistic assumptions. A common unrealistic assumption in using EPQ is that all units produced are of good quali ty. The classical EPQ model shows that the optimal lot size will generate minimum ma nufacturing cost, thus producing minimum setup cost and inventory cost. However, this is only true if all products manufactured in the process are assumed to be of good quality (i.e. all products are within the specification limits). In rea lity this is not the case, therefore, it is necessary to consider the cost of im perfect quality items, because this cost can influence the economic lot size. Ma ny studies and recent papers have indicated that there is a significant relation ship between economic production lot size and process/product quality. However, their models included either the imperfect quality items (not necessarily de fective) which are to be sold at a discounted price or defective items which can be reworked or rejected. The aim of this paper is to provide a framework to integrate three different sit uations (discounted pricing/rework/reject) into a single model. 100% inspection is performed in order to distinguish the amount of good quality items, imper fect quality items and defective items in each lot. In this paper, a mathematica l model is developed, and a numerical example is presented to illustrate the sol ution procedures. It is found that the economic production lot size tends to inc rease as the average percentage of imperfect quality items and defectives (rejec ted items) increases.展开更多
For the unsorted database quantum search with the unknown fraction λ of target items, there are mainly two kinds of methods, i.e., fixed-point and trail-and-error.(i) In terms of the fixed-point method, Yoder et al. ...For the unsorted database quantum search with the unknown fraction λ of target items, there are mainly two kinds of methods, i.e., fixed-point and trail-and-error.(i) In terms of the fixed-point method, Yoder et al. [Phys. Rev. Lett.113 210501(2014)] claimed that the quadratic speedup over classical algorithms has been achieved. However, in this paper, we point out that this is not the case, because the query complexity of Yoder’s algorithm is actually in O(1/λ01/2)rather than O(1/λ1/2), where λ0 is a known lower bound of λ.(ii) In terms of the trail-and-error method, currently the algorithm without randomness has to take more than 1 times queries or iterations than the algorithm with randomly selected parameters. For the above problems, we provide the first hybrid quantum search algorithm based on the fixed-point and trail-and-error methods, where the matched multiphase Grover operations are trialed multiple times and the number of iterations increases exponentially along with the number of trials. The upper bound of expected queries as well as the optimal parameters are derived. Compared with Yoder’s algorithm, the query complexity of our algorithm indeed achieves the optimal scaling in λ for quantum search, which reconfirms the practicality of the fixed-point method. In addition, our algorithm also does not contain randomness, and compared with the existing deterministic algorithm, the query complexity can be reduced by about 1/3. Our work provides a new idea for the research on fixed-point and trial-and-error quantum search.展开更多
The progressive aging of society has become a global concern, and is expected to lead to the development of effective, sustainable, person-centered, integrated community-based care systems. However, there is insuffici...The progressive aging of society has become a global concern, and is expected to lead to the development of effective, sustainable, person-centered, integrated community-based care systems. However, there is insufficient evidence regarding effective integrated community-based care. In particular, few studies have focused on social aspects of the community environment related to elderly health. This study aimed to consider social aspects as evaluation items, focusing particularly on social determinants from the perspective of community-dwelling people, to explore truly effective integrated community-based care to improve elderly health. The definition of social determinants means social cohesion in social and community contexts. A literature review of English articles published in peer-reviewed journals up to October 2019 was conducted using PubMed, MEDLINE, and CINAHL with the following search terms: “social cohesion,” “elderly health,” “mental health” and “community.” Identified articles were screened based on title and abstract, and selected articles were subjected to full-text assessment and critical review. All references cited in the selected articles were also reviewed. The following inclusion criteria were used: 1) studies targeting community-dwelling elderly people or community-dwelling people including elderly people as participants;2) studies with clear descriptions of social factors in the Methods section;and 3) studies with clear descriptions of health-related items in the Methods section. From the 21 articles analyzed, of which 9 articles defined social determinants as social cohesion in social and community context, 37 items were extracted as social aspects at the community level that reflect the perspective of residents. These items can be developed as evaluation items for community-based health care outcomes through consensus among community health care providers and further investigation.展开更多
In this paper, we propose a deteriorating items inventory model with constant demand and deterioration rates, and mixed cargo transportation modes. The transportation modes are full container load (FCL) and less than ...In this paper, we propose a deteriorating items inventory model with constant demand and deterioration rates, and mixed cargo transportation modes. The transportation modes are full container load (FCL) and less than container load (LCL). Deteriorating items, such as specialty gases which are applied in semiconductor fabrication, deteriorate owing to environmental variation. Exact algorithms are proposed to determine the optimal inventory policies over a finite and an infinite planning horizon. Numerical examples are given to illustrate the proposed solution procedures. In addition, when the deterioration rate is large, the results of the proposed model perform better compared to the inventory model proposed by Rieksts and Ventura (2008).展开更多
To improve high quality and/or retain achieved high quality of an academic program, time to time evaluation for quality of each covered course is often an integrated aspect considered in reputed institutions, however,...To improve high quality and/or retain achieved high quality of an academic program, time to time evaluation for quality of each covered course is often an integrated aspect considered in reputed institutions, however, there has been little effort regarding humanities courses. This research article deals with analysis of evaluation data collected regarding humanities course from a College of Commerce & Economics, Mumbai, Maharashtra, India, on Likert type items. Appropriateness of one parametric measure and three non-parametric measures are discussed and used in this regard which could provide useful clues for educational policy planners. Keeping in view of the analytical results using these four measures, regardless of the threshold regarding satisfaction among students, overall performance of almost every subject has been un-satisfactory. There is a need to make a focused approach to take every course at the level of high performance. The inconsistency noticed under every threshold further revealed that under such poorly performing subjects globally, one needs to analyze merely at the global level item. Once the global level analysis reveals high performance of a course, then only item specific analysis may need to be focused to find out the items requiring further improvements.展开更多
In this paper, a new algorithm HCOUNT ＋ is proposed to find frequent items over data stream based on the HCOUNT algorithm. The new algorithm adopts aided measures to improve the precision of HCOUNT greatly. In additi...In this paper, a new algorithm HCOUNT ＋ is proposed to find frequent items over data stream based on the HCOUNT algorithm. The new algorithm adopts aided measures to improve the precision of HCOUNT greatly. In addition,HCOUNT ＋ is introduced to time critical applications and a novel sliding windows-based algorithm SL-HCOUNT ＋ is proposed to mine the most frequent items occurring recently.This algorithm uses limited memory （nB · （1 ＋α） · e/ε·In（-M/lnρ）（α〈1） counters）, requires constant processing time per packet （only （1＋α） · ln（-M/lnρ（α〈1）） counters are updated）, makes only one pass over the streaming data,and is shown to work well in the experimental results.展开更多
During the installation of a pipe pile,the soil around the pile will be squeezed out. This paper deals with this squeezing effect of open-ended pipe piles using the cylindrical cavity expansion theory. The characteris...During the installation of a pipe pile,the soil around the pile will be squeezed out. This paper deals with this squeezing effect of open-ended pipe piles using the cylindrical cavity expansion theory. The characteristics of soil with different tension and compression moduli and dilation are involved by applying the elastic theory with different moduli and logarithmic strain. The closed-form solutions of the radius of the plastic region,the displacement of the boundary between the plastic region and the elastic region and the expansion pressure on the external surface of the pipe piles are obtained. When obtaining these solutions,the soil plug in the open-ended pipe pile is considered by employing an incremental filling ratio to quantify the degree of soil plugging. Moreover,the effects of the ratio of tension and compression moduli,angle of dilation and incremental filling ratio on the radius of the plastic region and the expansion pressure on the external surface of the pipe pile are investigated. The parametric analyses show that it is necessary and important to consider the difference between the tension modulus and compression modulus,dilation angle and incremental filling ratio for studying the squeezing effect of open-ended pipe pile installation. It is concluded that the analytical solutions presented in this paper are suitable for studying the squeezing effect of open-ended pipe piles.展开更多
Difference in environmental condition shapes variation in digestive tract length in evolutionary process.In particular,environmental difference results in variation in food resource among different habitats,and thereb...Difference in environmental condition shapes variation in digestive tract length in evolutionary process.In particular,environmental difference results in variation in food resource among different habitats,and thereby affecting energy intake and energy allocation.The digestive theory predicts that animals foraging high indigestible materials of stomach contents can promote the increased gut dimensions.Here,we studied variation in digestive tract and gut length across six Hylarana guentheri populations at different altitudes and latitudes to test the prediction of the digestive theory.We found that altitude and latitude did not affect variation in relative size of digestive tract and gut among populations.We also found that relative size of digestive tract and gut did not be correlated with diversity of prey items,but negatively correlated with proportion of digestible materials.Our findings suggest that individuals foraging less digestible materials display relatively longer digestive tract than individuals foraging more digestible materials.展开更多
基金China Ministry of Industry and Information Technology for High-Tech Ship Project。
文摘The inbound and outbound tasks for valuable imported ship outfitting items are operated by multiple automated guided vehicles(AGVs)simultaneously in the outfitting warehouse.Given the efficiency mismatch between transportation equipment and the lack of effective scheduling of AGVs,the objective of the studied scheduling problem is to minimize the total travel time cost of vehicles.A multi-AGV task scheduling model based on time window is established considering the loading constraints of AGVs and cooperation time window constraints of stackers.According to the transportation characteristics in the outfitting warehouse,this study pro-poses a conflict detection method for heavy forklift AGVs,and correspondingly defines a conflict penalty function.Furthermore,to comprehensively optimize travel time cost and conflict penalty,a hybrid genetic neighborhood search algorithm(GA-ANS)is proposed.Five neighborhood structures are designed,and adaptive selection opera-tors are introduced to enhance the ability of global search and local chemotaxis.Numerical experiments show that the proposed GA-ANS algorithm can effectively solve the problem even when the scale of the problem increases and the effectiveness of the vehicle conflict penalty strategy is analyzed.
基金by the Guangdong Basic and Applied Basic Research Foundation under Grant 2021B1515120064.
文摘In real-world scenarios,dual-view X-ray machines have outnumbered single-view X-ray machines due to their ability to provide comprehensive internal information about the baggage,which is important for identifying prohibited items that are not visible in one view due to rotation or overlap.However,existing work still focuses mainly on single-view,and the limited dual-viewbasedwork only performs simple information fusion at the feature or decision level and lacks effective utilization of the complementary information hidden in dual view.To this end,this paper proposes an end-to-end dual-view prohibited item detection method,the core of which is an adaptive material-aware coordinate-aligned attention module(MACA)and an adaptive adjustment strategy(AAS).Specifically,we observe that in X-ray images,the material information of an object can be represented by color and texture features,and remains consistent across views,even under complex backgrounds.Therefore,our MACA first integrates the material information of the prohibited items in each view and then smoothly transfers these clearmaterial clues along the shared axis to the corresponding locations in the other view to enhance the feature representation of the blurred prohibited items in the other view.In addition,AAS can autonomously adjust the importance of the two views during feature learning to make joint optimizationmore stable and effective.Experiments on the DvXray dataset demonstrate that the proposed MACA and AAS can be plug-and-played into various detectors,such as Faster Region-based Convolutional Neural Network(Faster R-CNN)and Fully Convolutional One-Stage Object Detector(FCOS),and bring consistent performance gains.The entire framework performs favorably against state-of-the-art methods,especially on small-sized prohibited items,highlighting its potential application in reality.
文摘Loneliness is a complex and usually unpleasant emotional response to isolation,which has been considered the latest global health epidemic exacerbated by the coronavirus disease 2019 pandemic,affecting nearly twothirds of older adults.Some profound health implications carried by loneliness include depression,cognitive impairment,hypertension and frailty.Across the world,there is no consensus definition of loneliness,and its measure is based on the phenomenological perspective of the individual.The 20-item University of California Los Angeles Loneliness Scale version 3(UCLA-20)is the most common measure.This scale demonstrates acceptable psychometric properties but is too long and complex for a phone interview.This paper addresses the increasing need to shorten this scale by adopting classical item response theory and network psychometrics to advance scale development.Through an item reduction analysis,we trimmed the original scale into an effective short form,which is as valid as the original one.With respondents’time at a premium in most research nowadays,this shortform scale is an efficient and practical alternative to the original UCLA-20.
基金supported by the National Natural Science Foundation of China(No.61806208)the Fundamental Research Funds for the Central Universities(No.3122018S008)the Tianjin Education Committee Research Project(No.2018KJ246)。
文摘In this paper,we focus on the detection of prohibited items with small size,and establish an automatic detection model based on feature fusion single shot multibox detector(FSSD)architecture.Two modifications are carried out to improve the detection accuracy.Firstly,the semantic enrichment module(SEM)with dilated convolution is applied to extract the low level feature with strong semantic information.Secondly,a residual module(Res)with residual blocks is added in the multibox detection architecture in order to extract more adequate features for target detection.The simulation results have demonstrated a better performance of the proposed detection model for prohibited items with small size compared with the state-of-the-arts.
文摘In recent times, mathematical models have been developed to describe various scenarios obtainable in the management of inventories. These models usually have as objective the minimizing of inventory costs. In this research work we propose a mathematical model of an inventory system with time-dependent three-parameter Weibull deterioration and a stochastic type demand in the form of a negative exponential distribution. Explicit expressions for the optimal values of the decision variables are obtained. Numerical examples are provided to illustrate the theoretical development.
文摘In intercontinental trade and economics goods are bought from a global supplier.On occasion,the expected lot may include a fraction of defective items.These imperfect items still have worth and can be sold to customers after repair.It is cost-effective and sustainable to rework such items in nearby repair workshops rather than return them.The reworked items can be returned from the workshop to the buyer when shortages are equal to the quantity of imperfect items.In the meantime,the supplier correspondingly deals a multi-period delay-in-payments strategy with purchaser.The entire profit has been maximized with paybacks for interim financing.This study aims to develop a synergic inventory model to get the most profit by making an allowance for reworking,multi-period delay-in-payments policy,and shortages.The findings of the proposed model augment inventory management performance by monitoring cycle time as well as fraction of phase with optimistic inventory for a supply chain.The results demonstrate that profit is smaller if the permitted period given by supplier to buyer is equal to or greater than the cycle time,and profit is greater if the permitted period is smaller than the cycle time.The algebraic method is engaged to make a closed system optimum solution.The mathematical experiment of this study is constructed to provide management insights and tangible practices.
基金Innovative and Entrepreneurial Team Program of Jiangsu Province,China,Grant/Award Number:JSSCTD202140Innovative and Entrepreneurial Doctor Program of Jiangsu Province,Grant/Award Number:KYCX20_0114National Natural Science Foundation of China,Grant/Award Numbers:41831281,52104121。
文摘Microwave fracturing of rocks before mechanical breakage could improve the performance of mechanical excavators and reduce environmental impacts.Previous research focused on the microwave fracturing of intact rock blocks.By using an open-ended antenna,this paper investigates the effect of pre-existing joints on the microwave fracturing of the Singapore Bukit Timah granite blocks.The results show that the specimens are weakened in the manners of cracking,spalling,melting,or a combination of them.The crack number and the total crack length produced by microwave treatment of jointed rock blocks are slightly smaller than those in the intact rock blocks.The interaction between joints and microwave-induced cracks can be summarized into the following four patterns:(1)microwave-induced cracks become arrested so that the crack propagation is terminated;(2)microwave-induced cracks penetrate the joints and continue to propagate;(3)microwave-induced cracks become deflected along the joints;and(4)microwave-induced cracks propagate forward following the joints.The smaller the approach angle between the microwave-induced crack and the preexisting joint is,the more microwave-induced cracks tend to be arrested at the joint.Increasing the approach angle between the microwave-induced crack and the joint can increase the chance of microwave-induced crack penetrating the joint.The results also show that the smaller the distance is between the microwave radiation point and the joint,the easier it is for microwave-induced cracks to penetrate the joints;otherwise,the microwave-induced crack is more likely to be arrested at the pre-existing joint.
文摘The article deals with an economic order quantity (EOQ) inventory model for deteriorating items in which the supplier provides the purchaser a permissible delay in payment. This is so when deterioration of units in the inventory is subject to constant deterioration rate, demand rate is quadratic function of time and salvage value is associated with the deteriorated units. Shortages in the system are not allowed to occur. A mathematical formulation is developed when the supplier offers a permissible delay period to the customers under two circumstances: 1) when delay period is less than the cycle of time;and 2) when delay period is greater than the cycle of time. The method is suitable for the items like state-of-the-art aircrafts, super computers, laptops, android mobiles, seasonal items and machines and their spare parts. A solution procedure algorithm is given for finding the optimal order quantity which minimizes the total cost of an inventory system. The article includes numerical examples to support the effectiveness of the developed model. Finally, sensitivity analysis on some parameters on optimal solution is provided.
文摘The international financial reporting standard for cash flow statement （IAS 7） provides options for the classification of certain cash flow items （arbitrary items）. Therefore, business firms may classify the arbitrary items using the option that would maximize their own interest. This reduces the comparability of financial statements amongst business firms. This study aims to investigate the factors explaining management preferences in the selection of financial reporting practices on the arbitrary cash flow items. It concludes that managers tend to magnify the CFO reported in order to maximize the shareholders＇ wealth, which in turn would maximize their compensation. Managers of business firms with a relatively smaller size of CFO tend to classify interest paid and dividends paid as non-CFO in order to magnify their CFO. They also tend to classify interest received as CFO in order to inflate their relatively smaller size of CFO up to expectation. Similarly, managers of business firms with a relative larger size of dividends paid would classify the dividends paid outside CFO.
文摘The 19th National Congress of the Communist Party of China is a meeting of great importance held during the decisivestage of building a moderately prosperous society in all respects.As a window to know about the latest changes of China,it is au-thoritative and of much value to study.As time goes by,there emerge more lexical items with Chinese characteristics.This articlestudies Chinese-English translation skills of lexical items with Chinese Characteristics in the Report on the 19th National Congressof the CPC.First,it classifies these lexical items into several kinds including those related with economy,politics,culture,peo-ple’s wellbeing and other lexical items,and then studies them respectively.
文摘The classical EPQ model has been used for a long ti me and is widely accepted and implemented. Nevertheless, the analysis for finding an economic lot size has based on a number of unrealistic assumptions. A common unrealistic assumption in using EPQ is that all units produced are of good quali ty. The classical EPQ model shows that the optimal lot size will generate minimum ma nufacturing cost, thus producing minimum setup cost and inventory cost. However, this is only true if all products manufactured in the process are assumed to be of good quality (i.e. all products are within the specification limits). In rea lity this is not the case, therefore, it is necessary to consider the cost of im perfect quality items, because this cost can influence the economic lot size. Ma ny studies and recent papers have indicated that there is a significant relation ship between economic production lot size and process/product quality. However, their models included either the imperfect quality items (not necessarily de fective) which are to be sold at a discounted price or defective items which can be reworked or rejected. The aim of this paper is to provide a framework to integrate three different sit uations (discounted pricing/rework/reject) into a single model. 100% inspection is performed in order to distinguish the amount of good quality items, imper fect quality items and defective items in each lot. In this paper, a mathematica l model is developed, and a numerical example is presented to illustrate the sol ution procedures. It is found that the economic production lot size tends to inc rease as the average percentage of imperfect quality items and defectives (rejec ted items) increases.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11504430 and 61502526)the National Basic Research Program of China(Grant No.2013CB338002)
文摘For the unsorted database quantum search with the unknown fraction λ of target items, there are mainly two kinds of methods, i.e., fixed-point and trail-and-error.(i) In terms of the fixed-point method, Yoder et al. [Phys. Rev. Lett.113 210501(2014)] claimed that the quadratic speedup over classical algorithms has been achieved. However, in this paper, we point out that this is not the case, because the query complexity of Yoder’s algorithm is actually in O(1/λ01/2)rather than O(1/λ1/2), where λ0 is a known lower bound of λ.(ii) In terms of the trail-and-error method, currently the algorithm without randomness has to take more than 1 times queries or iterations than the algorithm with randomly selected parameters. For the above problems, we provide the first hybrid quantum search algorithm based on the fixed-point and trail-and-error methods, where the matched multiphase Grover operations are trialed multiple times and the number of iterations increases exponentially along with the number of trials. The upper bound of expected queries as well as the optimal parameters are derived. Compared with Yoder’s algorithm, the query complexity of our algorithm indeed achieves the optimal scaling in λ for quantum search, which reconfirms the practicality of the fixed-point method. In addition, our algorithm also does not contain randomness, and compared with the existing deterministic algorithm, the query complexity can be reduced by about 1/3. Our work provides a new idea for the research on fixed-point and trial-and-error quantum search.
文摘The progressive aging of society has become a global concern, and is expected to lead to the development of effective, sustainable, person-centered, integrated community-based care systems. However, there is insufficient evidence regarding effective integrated community-based care. In particular, few studies have focused on social aspects of the community environment related to elderly health. This study aimed to consider social aspects as evaluation items, focusing particularly on social determinants from the perspective of community-dwelling people, to explore truly effective integrated community-based care to improve elderly health. The definition of social determinants means social cohesion in social and community contexts. A literature review of English articles published in peer-reviewed journals up to October 2019 was conducted using PubMed, MEDLINE, and CINAHL with the following search terms: “social cohesion,” “elderly health,” “mental health” and “community.” Identified articles were screened based on title and abstract, and selected articles were subjected to full-text assessment and critical review. All references cited in the selected articles were also reviewed. The following inclusion criteria were used: 1) studies targeting community-dwelling elderly people or community-dwelling people including elderly people as participants;2) studies with clear descriptions of social factors in the Methods section;and 3) studies with clear descriptions of health-related items in the Methods section. From the 21 articles analyzed, of which 9 articles defined social determinants as social cohesion in social and community context, 37 items were extracted as social aspects at the community level that reflect the perspective of residents. These items can be developed as evaluation items for community-based health care outcomes through consensus among community health care providers and further investigation.
文摘In this paper, we propose a deteriorating items inventory model with constant demand and deterioration rates, and mixed cargo transportation modes. The transportation modes are full container load (FCL) and less than container load (LCL). Deteriorating items, such as specialty gases which are applied in semiconductor fabrication, deteriorate owing to environmental variation. Exact algorithms are proposed to determine the optimal inventory policies over a finite and an infinite planning horizon. Numerical examples are given to illustrate the proposed solution procedures. In addition, when the deterioration rate is large, the results of the proposed model perform better compared to the inventory model proposed by Rieksts and Ventura (2008).
文摘To improve high quality and/or retain achieved high quality of an academic program, time to time evaluation for quality of each covered course is often an integrated aspect considered in reputed institutions, however, there has been little effort regarding humanities courses. This research article deals with analysis of evaluation data collected regarding humanities course from a College of Commerce & Economics, Mumbai, Maharashtra, India, on Likert type items. Appropriateness of one parametric measure and three non-parametric measures are discussed and used in this regard which could provide useful clues for educational policy planners. Keeping in view of the analytical results using these four measures, regardless of the threshold regarding satisfaction among students, overall performance of almost every subject has been un-satisfactory. There is a need to make a focused approach to take every course at the level of high performance. The inconsistency noticed under every threshold further revealed that under such poorly performing subjects globally, one needs to analyze merely at the global level item. Once the global level analysis reveals high performance of a course, then only item specific analysis may need to be focused to find out the items requiring further improvements.
文摘In this paper, a new algorithm HCOUNT ＋ is proposed to find frequent items over data stream based on the HCOUNT algorithm. The new algorithm adopts aided measures to improve the precision of HCOUNT greatly. In addition,HCOUNT ＋ is introduced to time critical applications and a novel sliding windows-based algorithm SL-HCOUNT ＋ is proposed to mine the most frequent items occurring recently.This algorithm uses limited memory （nB · （1 ＋α） · e/ε·In（-M/lnρ）（α〈1） counters）, requires constant processing time per packet （only （1＋α） · ln（-M/lnρ（α〈1）） counters are updated）, makes only one pass over the streaming data,and is shown to work well in the experimental results.
文摘During the installation of a pipe pile,the soil around the pile will be squeezed out. This paper deals with this squeezing effect of open-ended pipe piles using the cylindrical cavity expansion theory. The characteristics of soil with different tension and compression moduli and dilation are involved by applying the elastic theory with different moduli and logarithmic strain. The closed-form solutions of the radius of the plastic region,the displacement of the boundary between the plastic region and the elastic region and the expansion pressure on the external surface of the pipe piles are obtained. When obtaining these solutions,the soil plug in the open-ended pipe pile is considered by employing an incremental filling ratio to quantify the degree of soil plugging. Moreover,the effects of the ratio of tension and compression moduli,angle of dilation and incremental filling ratio on the radius of the plastic region and the expansion pressure on the external surface of the pipe pile are investigated. The parametric analyses show that it is necessary and important to consider the difference between the tension modulus and compression modulus,dilation angle and incremental filling ratio for studying the squeezing effect of open-ended pipe pile installation. It is concluded that the analytical solutions presented in this paper are suitable for studying the squeezing effect of open-ended pipe piles.
基金Financial support was provided by the National Natural Sciences Foundation of China(31772451,31970393)the Science and Technology Youth Innovation Team of Sichuan Province(19CXTD0022)+1 种基金the Key Cultivation Foundation of China West Normal University(17A006)Talent Project of China West Normal University(17YC335)。
文摘Difference in environmental condition shapes variation in digestive tract length in evolutionary process.In particular,environmental difference results in variation in food resource among different habitats,and thereby affecting energy intake and energy allocation.The digestive theory predicts that animals foraging high indigestible materials of stomach contents can promote the increased gut dimensions.Here,we studied variation in digestive tract and gut length across six Hylarana guentheri populations at different altitudes and latitudes to test the prediction of the digestive theory.We found that altitude and latitude did not affect variation in relative size of digestive tract and gut among populations.We also found that relative size of digestive tract and gut did not be correlated with diversity of prey items,but negatively correlated with proportion of digestible materials.Our findings suggest that individuals foraging less digestible materials display relatively longer digestive tract than individuals foraging more digestible materials.
