By exploring the application of piano in Chinese pop music arrangements,this article aims to enhance the understanding of the position of piano in pop music and provide useful insights and references for the future de...By exploring the application of piano in Chinese pop music arrangements,this article aims to enhance the understanding of the position of piano in pop music and provide useful insights and references for the future development of Chinese pop music.Starting from the unique position of piano in Chinese pop music arrangements,the article analyses in detail the specific applications of piano in Chinese pop music arrangements.The analysis finds that the piano has been deeply integrated into the bloodline of Chinese popular music and become an indispensable part.From simple melodic embellishments to complex arrangement ideas,the piano has injected endless vitality and vigor into popular music with its unique timbre and expressive power.展开更多
[Objective] The aim was to provide a theoretical basis for stable and highly effective intercropping arrangements and scientific management measures by selecting apple, pear, peach, apricot, walnut, jujube and other f...[Objective] The aim was to provide a theoretical basis for stable and highly effective intercropping arrangements and scientific management measures by selecting apple, pear, peach, apricot, walnut, jujube and other fruit trees to study their influence on yield, fiber quality and economic returns of intercropped cotton in southern Xinjiang. [Method] Based on major cropping pattern in production, randomized block design was adopted to explore growth indicators, canopy micrometeorological indicators, yield and fiber quality in key growth stage. [Result] Shading has a significant effect on cotton canopy micro-environment and canopy diameter is proportional to shading effect. According to comparisons of the same tree type, the change of canopy micro-environment was as follows: under canopyouter canopymiddle points and peachpearapplewalnutjujube for comparisons among different tree types. Canopy diameter is directly proportional to the number of tree branch and boll weight reductions and shading is the main cause of yield reduction. The canopy expansion is the major cause of decline of light intensity, temperature and humidity of cotton canopy. [Conclusion] Fruit trees, which will promote cotton yield,quality and canopy-environment, are as follows: jujube walnut apple pear peach trees. In practice, trees, which are small in canopy or well trimmed, are popular in production, such as jujube trees, to improve cotton yield and fiber quality.展开更多
In this study, a computer code is developed to numerically investigate a magnetic bead micromixer under different conditions. The micromixer consists of a microchannel and numerous micro magnetic particles which enter...In this study, a computer code is developed to numerically investigate a magnetic bead micromixer under different conditions. The micromixer consists of a microchannel and numerous micro magnetic particles which enter the micromixer by fluid flows and are actuated by an alternating magnetic field normal to the main flow. An important feature of micromixer which is not considered before by researchers is the particle entrance arrangement into the micromixer. This parameter could effectively affect the micromixer efficiency. There are two general micro magnetic particle entrance arrangements in magnetic bead micromixers: determined position entrance and random position entrance. In the case of determined position entrances, micro magnetic particles enter the micromixer at specific positions of entrance cross section. However, in a random position entrance,particles enter the microchannel with no order. In this study mixing efficiencies of identical magnetic bead micromixers which only differ in particle entrance arrangement are numerically investigated and compared.The results reported in this paper illustrate that the prepared computer code can be one of the most powerful and beneficial tools for the magnetic bead micromixer performance analysis. In addition, the results show that some features of the magnetic bead micromixer are strongly affected by the entrance arrangement of the particles.展开更多
Objective This study aimed to examine the sleep arrangements and soothing methods and to assess their associations with sleep problems among children aged<3 years in China.Methods A cross-sectional survey was condu...Objective This study aimed to examine the sleep arrangements and soothing methods and to assess their associations with sleep problems among children aged<3 years in China.Methods A cross-sectional survey was conducted in 2019 from six provinces in China.A total of 1,195 caregivers of children aged 0–35 months were included in the study.Data on sleep arrangements,soothing methods,and sleep problems(i.e.,frequent night awakenings and difficulty falling asleep)were assessed using the Brief Infant Sleep Questionnaire.The reasons for bed-sharing in sleep arrangements were recorded using a self-designed questionnaire.Results The bed-sharing practice was very prevalent at any age,which ranged from 69.9%to 78.3%.Most infants fell asleep while feeding or being rocked/held before age 12 months.By age 35 months,62.4%of the children fell asleep in bed near parents.The most common reasons for bed-sharing were breastfeeding/feeding and convenience.Parental involvement when falling asleep was significantly related with frequent night awakenings and difficulty falling asleep.No association was found between bed-sharing and sleep.Conclusion Bed-sharing and parental involvement were very common among Chinese children aged<3 years.Children who fall asleep with parental involvement were more likely to have sleep problems.展开更多
Numerical studies on transient heat transfer characteristics of air-array-jet impingement with a small jet-to-plate distance and a large temperature difference between nozzles and plate were presented.The dimensionles...Numerical studies on transient heat transfer characteristics of air-array-jet impingement with a small jet-to-plate distance and a large temperature difference between nozzles and plate were presented.The dimensionless jet-to-plate distance(H/D)was 0.2,and non-dimensional nozzle-to-nozzle spacing(S/D)was 3,4,5 and 6,respectively.It is found that the quenching time is shortened at a constant total mass flow at air jet inlet m·(m·=218.21 kg/h),and the heat transfer uniformity is deterio-rated as S/D increases.However,the adding reversed-flow nozzles can shorten the quenching time of the glass plate considerably with a modest change in the heat transfer uniformity.The results at variable m·are the same as those at a fixed m·.Furthermore,the parity and arrangement of nozzles are also discussed,It is found that an odd number of nozzles is more beneficial for transient heat transfer.Based on these results,an appropriate proposal for ultra-thin glass tempering process is presented.展开更多
The arrangement of electrolyte inlet in the copper electro-refining(ER)cell has a great influence on the local flow field,which affects the distribution of electrical current density in consequence.In order to underst...The arrangement of electrolyte inlet in the copper electro-refining(ER)cell has a great influence on the local flow field,which affects the distribution of electrical current density in consequence.In order to understand the complicated phenomena ofelectrolyte flow behavior in vertical counter electrodes in full-scale copper ER cell,the three-dimensional computational fluiddynamics(CFD)models with four different arrangements of electrolyte inlets,i.e.,single inlet(SI),central bottom inlets(CBI),topside interlaced inlets(TII),and bottom side interlaced inlets(BII),were established to simulate the flow behavior.Simulation resultshave revealed that the parallel injection devices help to improve the electrolyte velocity between electrodes,and while the relativerange of electrolyte velocity in CBI exceeds that of TII and BII,which is more than4times,indicating its severer unequal flowdistribution.Meanwhile,the average velocity of electrolyte in BII is4times larger than that of SI due to its higher turbulenceintensity.Generally,one of the efficient ways to supply fresh copper solution rapidly and uniformly into the inter-electrode space is toadapt the arrangement of BII.By utilizing such an arrangement,the electro-refining under high electrical current density is possible,and the productivity can be increased in sequence.展开更多
With Multi-Fiber Arrangement (MFA) eliminated on Dec 31, 2004, the debates and concerns on the trade of textile and apparel have been growing. The objective of this study is to examine the impacts of alternative polic...With Multi-Fiber Arrangement (MFA) eliminated on Dec 31, 2004, the debates and concerns on the trade of textile and apparel have been growing. The objective of this study is to examine the impacts of alternative policies on China and World economy after canceling MFA. Based on a general equilibrium model of the Global Trade Analysis Project (GTAP), study shows that China and World will significantly benefit from further trade liberalization. However, if USA, EU and Canada converted to TBT to restrict import, the gains from eliminating MFA would be largely offset. Based on our analysis, some policy implications are discussed.展开更多
This paper exemplifies a primary step towards eliciting primary and secondary stakeholders’ views on management issues pertaining to kingfish fishery in Oman, and potential options for effective management of the fis...This paper exemplifies a primary step towards eliciting primary and secondary stakeholders’ views on management issues pertaining to kingfish fishery in Oman, and potential options for effective management of the fishery using questionnaire surveys and focus group interviews. There was consensus from stakeholder groups which included fishers, fishery managers, and fishery scientists that the current stock condition is not biologically sustainable. It is found that fishing effort control and technical measures are preferred to catch control by both groups. The role of mass media and the traditional institution in communicating fisheries issues are found to be relatively minor. Although the overall rating on the comprehensiveness of the proposed plan is promising, there are significant differences between the two groups with regard to legislative arrangements (χ<sup>2</sup> = 24.793, p-value = 0.000), management goals (χ<sup>2</sup> = 16.206, p-value = 0.001), operational objectives (χ<sup>2</sup> = 19.884, p-value = 0.000), performance indicators (χ<sup>2</sup> = 15.524, p-value = 0.001), and measures (χ<sup>2</sup> = 13.483, p-value = 0.004). Policy implications of the key findings are discussed in both national and regional contexts. Management authorities can use these findings to design an appropriate plan of actions for achieving sustainability in this fishery.展开更多
We consider a central hyperplane arrangement in a three-dimensional vector space. The definition of characteristic form to a hyperplane arrangement is given and we could make use of characteristic form to judge the re...We consider a central hyperplane arrangement in a three-dimensional vector space. The definition of characteristic form to a hyperplane arrangement is given and we could make use of characteristic form to judge the reducibility of this arrangement. In addition, the relationship between the reducibility and freeness of a hyperplane arrangement is given展开更多
The coherent exciton plays an important role in the photosynthetic primary process, and its functions are deeply dependent on the orientation arrangements of local transition dipole moments (TDMs). We theoretically ...The coherent exciton plays an important role in the photosynthetic primary process, and its functions are deeply dependent on the orientation arrangements of local transition dipole moments (TDMs). We theoretically and systematically study the physical property of the coherent exciton at different orientation arrangements of the local TDMs in circular light-harvesting (LH) complexes. Especially, if the orientation arrangements are different, the delocalized TDMs of the coherent excitons and the energy locations of the optically active coherent excitons (OACEs) can be obviously different, and then there are more manners to capture, store and transfer light energy in and between LH complexes. Similarly, if the orientation arrangements are altered, light absorption and radiative intensities can be converted fully between the OACEs in the upper and lower coherent exciton bands, and then the blue and red shifts of the absorption and radiative bands of the pigment molecules can occur simultaneously at some orientation arrangements. If the systems are in the vicinities of the critical orientation arrangements, the weak static disorder or small thermal excitation can destroy the coherent electronic excitations, and then the coherent exciton cannot exist any more.展开更多
A simulation algorithm concerning problem B of 09 CUMCM is given. By introducing the concept of bed vector, clinic matrix, arrangement matrix and priority vector, the information about clinic, bed and arrangement will...A simulation algorithm concerning problem B of 09 CUMCM is given. By introducing the concept of bed vector, clinic matrix, arrangement matrix and priority vector, the information about clinic, bed and arrangement will be stored and analyzed via MATLAB. By the algorithm the continuously updating of data has been simulated successfully.展开更多
Living Cephalotaxus (plum yews) occurs mainly in East Asia and North of Indo-China peninsula. The study of original taxonomic literatures found that, in early days, the plum yews had ever been described as palnts of T...Living Cephalotaxus (plum yews) occurs mainly in East Asia and North of Indo-China peninsula. The study of original taxonomic literatures found that, in early days, the plum yews had ever been described as palnts of Taxus (Taxaceae). Since after the genus name Cephalotaxus Sieb. & Zucc. was firstly cited (from inedited and unpublished Flora Japonica) by Endlicher in 1842, most taxonomist thought which is the earliest time of the genus Cephalotaxus Sieb. & Zucc. was set. However, the genus Cephalotaxus Sieb. & Zucc. was formally effective and valid published by Sieb. & Zucc. in Flora Japonica in 1870 so that there exists some confusions in chronological order. Originally as a genus, Cephalotaxus was included in family Taxaceae and Neger (1907) separated Cephalotaxus from Taxaceae and set family Cephalotaxaceae. Later, Fu (1984) divided Cephalotaxus up into two sections of Cephalotaxus Sieb. & Zucc. sect. Pectinatae L. K. Fu and Cephalotaxus Sieb. & Zucc. sect. Cephalotaxus L. K. Fu on the bases of C. oliveri Masters differ significantly from other taxa of Cephalotaxus in morphological characteristics. Although the plum yews was a little genus of conifers, up to now, about 77 taxa have still been published by taxonomist in different countries or regions. Among them, C. tardiva Sieb. ex Endl. (1847), C. umbraculifera Sieb. ex Endl. (1847), C. sumatrana Miq. (1856) and C. celebica Warb. (1900) have been combined to Taxus, and C. argotaenia (Hance) Pilger (1903) has been combined to Amentotaxus. And at the same time, those taxa existing in Cephalotaxus courently which were accepted by most taxonomist in different countries was also cited in acticle. Lastly, the paper thought presently there still exists many debates about binary classification of Cephalotaxus and the nomenclature of this genus still particularly confusing. Based on some controversial problems, we also point out some taxonomically researching directions at creating some order out of the chaos.展开更多
Short circuit currents of power systems are growing with an increasing rate, due to the fast development of generation and transmission systems. Current Limiting Reactor is one of the effective short circuit current l...Short circuit currents of power systems are growing with an increasing rate, due to the fast development of generation and transmission systems. Current Limiting Reactor is one of the effective short circuit current limiting devices. This technique is known to be more practical than other available approaches. In this paper, proper application of CLR to HV substations is proposed, based on a comprehensive short circuit analysis of 4 well-known substation bus bar arrangements. Eventually, appropriate place and number of CLRs is recommended for each bus bar arrangement.展开更多
In Africa, ageing is a phenomenon that is just beginning to reveal its shape. Most governments, including the Namibian government, recognize the fact that the number of older persons is on the increase, however, discu...In Africa, ageing is a phenomenon that is just beginning to reveal its shape. Most governments, including the Namibian government, recognize the fact that the number of older persons is on the increase, however, discussing it is still a distant phenomenon and family matter. This paper examines the living arrangements of older adults in Namibia, identifying the existing structure of living arrangements and the nature of family relationships of older people, as well as provides some basic descriptive information on the housing conditions in which older persons live and how they are associated with their socioeconomic and demographic factors. The analysis is based on 1991, 2001 and 2011 Namibia Population and Housing Censuses. The study concluded that living arrangements is constantly changing from extended family pattern to western nuclear family, mainly due to urbanization and decreased fertility rate. Housing conditions had notably improved in rural areas while in urban areas the conditions are affected by the mushrooming of informal settlements. There is need to encourage or conduct focused research on ageing to help coin policies based on evidence and make communities sensitive towards ageing. The study further recommends Government to encourage old people to form organizations that would in turn focus on sensitizing and help championing issues of ageing and aged persons.展开更多
The proper establishment of loop-vessel countercurrent arrangement in medulla provides the basis for formation of the concentrated urine.To date,the morphogenesis of it has not been fully discovered.The present study ...The proper establishment of loop-vessel countercurrent arrangement in medulla provides the basis for formation of the concentrated urine.To date,the morphogenesis of it has not been fully discovered.The present study investigated the spatial arrangement of nephron loop and vessel of developing kidneys using 3D visualization technique and immunohistochemistry for AQP-1 and NKCC2.Five-mm-thick serial paraffin sections were obtained from E14.5 and P5 kidneys and stained with hematoxylin,while 2.5-mm-thick serial epoxy sections were obtained from E17.5 and P56 kidneys and stained with toluidine blue.展开更多
The possible states in the flow past two identical cylinders in tandem arrangements are investigated. The effect of the gap (L/D = 1.5, 1.75 and 2) between the two cylinders at Reynolds number (Re = 52,639) is tak...The possible states in the flow past two identical cylinders in tandem arrangements are investigated. The effect of the gap (L/D = 1.5, 1.75 and 2) between the two cylinders at Reynolds number (Re = 52,639) is taken into consideration. The presence of three-dimensional flow structures was observed to include notable changes to the response of the flow as result of variation of cylinder separation. A number of planes (z/h = 0.02, 0.25, 0.5 and 0.98) were taken at 20 step times of interval 0.005 s. to cover the details of flow along the cylinders. CFD FLUENT program was used to detect the flow structure. It is observed that the gap between the two cylinders affects the flow regime, i.e., there is no distinct vortex shedding downstream of the first cylinder.展开更多
The main features of morphological model of industrial robots are discussed, such as support system, manipulator and gripping device. These features are presented with the alternatives for their realization as separat...The main features of morphological model of industrial robots are discussed, such as support system, manipulator and gripping device. These features are presented with the alternatives for their realization as separate modules. The examples of synthesis of arrangements of industrial robots are resulted on module principle with writing of their morphological formulas.展开更多
A vortex-induced vibration(VIV)experiment of rough risers with coupling interference effect under a side-by-side arrangement was carried out in a wave-current combined flume.The roughness of the riser was characterize...A vortex-induced vibration(VIV)experiment of rough risers with coupling interference effect under a side-by-side arrangement was carried out in a wave-current combined flume.The roughness of the riser was characterized by arranging different specifications of surface attachments on the surface of the riser.Rough risers with three different roughnesses were arranged side by side with smooth risers to explore the VIV response of the riser under the combined action of roughness and interference effect,and to reveal the coupling mechanism between roughness and interference effect.The experimental results show that,compared with that of a smooth riser,the VIV of a rough riser under the coupling interference effect has a wider"lock-in"region,and the displacement decreases more significantly at a high reduced velocity,which is more likely to excite higher-order modes and frequency responses.In addition,the displacement response and frequency response of the smooth riser are not significantly affected by wake interference from the rough riser,which is caused by the decrease of the wake region due to the delay of the boundary layer separation point of the rough riser.展开更多
In order to study the response law of vortex-induced vibration(VIV)of marine risers under the combined action of roughness and interference effects,and to reveal the coupling mechanism of roughness and interference ef...In order to study the response law of vortex-induced vibration(VIV)of marine risers under the combined action of roughness and interference effects,and to reveal the coupling mechanism of roughness and interference effects on the riser,a VIV experiment of rough risers in tandem arrangement was conducted in a wave−current combined flume.The experiment characterized the risers’roughness by arranging different specifications of attachments on the surface of the risers.Three rough risers with different roughness and smooth risers were arranged in tandem arrangement,with the rough risers arranged downstream.The experimental results indicate that the suppression of the attachments on the downstream risers’vibration are more significant both in the CF and IL directions as the reduced velocity increases.For the downstream riser,the amplitude response of rough riser is more significantly weakened compared with the smooth one at high reduced velocity.For the upstream risers,changes in the roughness and spacing ratio have an impact on their‘lock-in’region.When the roughness of downstream risers is relatively large(0.1300)and the spacing between risers is small(S/D=4.0),the reduced velocity range of‘lock-in’region in the CF direction of upstream risers is obviously expanded,and the displacement in the‘lock-in’region is severer.展开更多
Background: Despite overwhelming evidence for gender differences in sleep quality as well as gender-specific changes of sleep parameters with respect to habitual sleeping arrangements, studies on snorers and their bed...Background: Despite overwhelming evidence for gender differences in sleep quality as well as gender-specific changes of sleep parameters with respect to habitual sleeping arrangements, studies on snorers and their bed partners have ignored the influence of individual quality of sleep as a potential co-factor. Objective: The objective of this study was to record subjective and objective sleep parameters and to analyze the effects of alternating of sleeping arrangements in snorers and their bed partners. Methods: Habitual snorers and their bed partners were recruited via newspaper articles not stating the exact purpose of the study. Both filled out a 90-day sleep diary. During this time, we recorded subjective and objective sleep parameters in the snorers and their bed partners via wrist actigraphy and sleep diaries for 14 days. For statistical analysis, we used two-sided t-tests and Spearman’s Rho. Results: The dataset included 45 snorers (11 females) and 45 bed partners (34 females) with a mean age of 47 ± 13 and 43 ± 12 years. Screening for sleep apnea yielded snoring without OSAS, mild-, moderate- and severe OSAS in 27 (60%), eight (18%), three (7%) and six (15%) snorers. PSQI total scores were significantly lower in snorers than in bed partners (4 ± 2 vs. 6 ± 4, p = 0.002). We could not find a significant correlation between subjective and objective sleep latency and efficiency. Couples who changed their sleeping arrangement were significantly younger than those who habitually slept alone or together (p = 0.01). Subjective sleep parameters of snorers or bed partners were not related to the number of consecutive nights spent either together or apart. Conclusions: Our study confirmed the weak correlation of subjective and objective sleep parameters in pairs with snoring problems. Couples changing their sleeping arrangement were the youngest among the whole group, but their separation of sleeping arrangements did not improve subjective sleep parameters.展开更多
文摘By exploring the application of piano in Chinese pop music arrangements,this article aims to enhance the understanding of the position of piano in pop music and provide useful insights and references for the future development of Chinese pop music.Starting from the unique position of piano in Chinese pop music arrangements,the article analyses in detail the specific applications of piano in Chinese pop music arrangements.The analysis finds that the piano has been deeply integrated into the bloodline of Chinese popular music and become an indispensable part.From simple melodic embellishments to complex arrangement ideas,the piano has injected endless vitality and vigor into popular music with its unique timbre and expressive power.
基金Supported by Special Foundation for Young Scientific and Technological Talents,Xinjiang Academy of Agricultural Sciences(xjnky-2012-009)Special Fund for Agroscientific Research in the Public Interest(201003043-07)+1 种基金Scientific Research Programof the Higher Education Institution of XinJiang(XJEDU2012S14)National-level College Students’Innovative Entrepreneurial Training Plan Program(201210758002)~~
文摘[Objective] The aim was to provide a theoretical basis for stable and highly effective intercropping arrangements and scientific management measures by selecting apple, pear, peach, apricot, walnut, jujube and other fruit trees to study their influence on yield, fiber quality and economic returns of intercropped cotton in southern Xinjiang. [Method] Based on major cropping pattern in production, randomized block design was adopted to explore growth indicators, canopy micrometeorological indicators, yield and fiber quality in key growth stage. [Result] Shading has a significant effect on cotton canopy micro-environment and canopy diameter is proportional to shading effect. According to comparisons of the same tree type, the change of canopy micro-environment was as follows: under canopyouter canopymiddle points and peachpearapplewalnutjujube for comparisons among different tree types. Canopy diameter is directly proportional to the number of tree branch and boll weight reductions and shading is the main cause of yield reduction. The canopy expansion is the major cause of decline of light intensity, temperature and humidity of cotton canopy. [Conclusion] Fruit trees, which will promote cotton yield,quality and canopy-environment, are as follows: jujube walnut apple pear peach trees. In practice, trees, which are small in canopy or well trimmed, are popular in production, such as jujube trees, to improve cotton yield and fiber quality.
文摘In this study, a computer code is developed to numerically investigate a magnetic bead micromixer under different conditions. The micromixer consists of a microchannel and numerous micro magnetic particles which enter the micromixer by fluid flows and are actuated by an alternating magnetic field normal to the main flow. An important feature of micromixer which is not considered before by researchers is the particle entrance arrangement into the micromixer. This parameter could effectively affect the micromixer efficiency. There are two general micro magnetic particle entrance arrangements in magnetic bead micromixers: determined position entrance and random position entrance. In the case of determined position entrances, micro magnetic particles enter the micromixer at specific positions of entrance cross section. However, in a random position entrance,particles enter the microchannel with no order. In this study mixing efficiencies of identical magnetic bead micromixers which only differ in particle entrance arrangement are numerically investigated and compared.The results reported in this paper illustrate that the prepared computer code can be one of the most powerful and beneficial tools for the magnetic bead micromixer performance analysis. In addition, the results show that some features of the magnetic bead micromixer are strongly affected by the entrance arrangement of the particles.
基金supported by the Science and Technology Innovation and Development Project of National Center for Women and Children’s Health,China CDC[2019KJ08]。
文摘Objective This study aimed to examine the sleep arrangements and soothing methods and to assess their associations with sleep problems among children aged<3 years in China.Methods A cross-sectional survey was conducted in 2019 from six provinces in China.A total of 1,195 caregivers of children aged 0–35 months were included in the study.Data on sleep arrangements,soothing methods,and sleep problems(i.e.,frequent night awakenings and difficulty falling asleep)were assessed using the Brief Infant Sleep Questionnaire.The reasons for bed-sharing in sleep arrangements were recorded using a self-designed questionnaire.Results The bed-sharing practice was very prevalent at any age,which ranged from 69.9%to 78.3%.Most infants fell asleep while feeding or being rocked/held before age 12 months.By age 35 months,62.4%of the children fell asleep in bed near parents.The most common reasons for bed-sharing were breastfeeding/feeding and convenience.Parental involvement when falling asleep was significantly related with frequent night awakenings and difficulty falling asleep.No association was found between bed-sharing and sleep.Conclusion Bed-sharing and parental involvement were very common among Chinese children aged<3 years.Children who fall asleep with parental involvement were more likely to have sleep problems.
基金Natural Science Foundation of China(51335002,51905049)。
文摘Numerical studies on transient heat transfer characteristics of air-array-jet impingement with a small jet-to-plate distance and a large temperature difference between nozzles and plate were presented.The dimensionless jet-to-plate distance(H/D)was 0.2,and non-dimensional nozzle-to-nozzle spacing(S/D)was 3,4,5 and 6,respectively.It is found that the quenching time is shortened at a constant total mass flow at air jet inlet m·(m·=218.21 kg/h),and the heat transfer uniformity is deterio-rated as S/D increases.However,the adding reversed-flow nozzles can shorten the quenching time of the glass plate considerably with a modest change in the heat transfer uniformity.The results at variable m·are the same as those at a fixed m·.Furthermore,the parity and arrangement of nozzles are also discussed,It is found that an odd number of nozzles is more beneficial for transient heat transfer.Based on these results,an appropriate proposal for ultra-thin glass tempering process is presented.
基金Project(61321003)supported by the National Natural Science Foundation of China
文摘The arrangement of electrolyte inlet in the copper electro-refining(ER)cell has a great influence on the local flow field,which affects the distribution of electrical current density in consequence.In order to understand the complicated phenomena ofelectrolyte flow behavior in vertical counter electrodes in full-scale copper ER cell,the three-dimensional computational fluiddynamics(CFD)models with four different arrangements of electrolyte inlets,i.e.,single inlet(SI),central bottom inlets(CBI),topside interlaced inlets(TII),and bottom side interlaced inlets(BII),were established to simulate the flow behavior.Simulation resultshave revealed that the parallel injection devices help to improve the electrolyte velocity between electrodes,and while the relativerange of electrolyte velocity in CBI exceeds that of TII and BII,which is more than4times,indicating its severer unequal flowdistribution.Meanwhile,the average velocity of electrolyte in BII is4times larger than that of SI due to its higher turbulenceintensity.Generally,one of the efficient ways to supply fresh copper solution rapidly and uniformly into the inter-electrode space is toadapt the arrangement of BII.By utilizing such an arrangement,the electro-refining under high electrical current density is possible,and the productivity can be increased in sequence.
基金Financial support from the National Science Foundation of China (70333001 and 70021001) is gratefully acknowledged. The paper has benefited from the advice from Prof. Frank van Tongeren in LEI and Prof. Weiming Tian in Chinese Agricultural University on technical and modeling aspects.
文摘With Multi-Fiber Arrangement (MFA) eliminated on Dec 31, 2004, the debates and concerns on the trade of textile and apparel have been growing. The objective of this study is to examine the impacts of alternative policies on China and World economy after canceling MFA. Based on a general equilibrium model of the Global Trade Analysis Project (GTAP), study shows that China and World will significantly benefit from further trade liberalization. However, if USA, EU and Canada converted to TBT to restrict import, the gains from eliminating MFA would be largely offset. Based on our analysis, some policy implications are discussed.
文摘This paper exemplifies a primary step towards eliciting primary and secondary stakeholders’ views on management issues pertaining to kingfish fishery in Oman, and potential options for effective management of the fishery using questionnaire surveys and focus group interviews. There was consensus from stakeholder groups which included fishers, fishery managers, and fishery scientists that the current stock condition is not biologically sustainable. It is found that fishing effort control and technical measures are preferred to catch control by both groups. The role of mass media and the traditional institution in communicating fisheries issues are found to be relatively minor. Although the overall rating on the comprehensiveness of the proposed plan is promising, there are significant differences between the two groups with regard to legislative arrangements (χ<sup>2</sup> = 24.793, p-value = 0.000), management goals (χ<sup>2</sup> = 16.206, p-value = 0.001), operational objectives (χ<sup>2</sup> = 19.884, p-value = 0.000), performance indicators (χ<sup>2</sup> = 15.524, p-value = 0.001), and measures (χ<sup>2</sup> = 13.483, p-value = 0.004). Policy implications of the key findings are discussed in both national and regional contexts. Management authorities can use these findings to design an appropriate plan of actions for achieving sustainability in this fishery.
文摘We consider a central hyperplane arrangement in a three-dimensional vector space. The definition of characteristic form to a hyperplane arrangement is given and we could make use of characteristic form to judge the reducibility of this arrangement. In addition, the relationship between the reducibility and freeness of a hyperplane arrangement is given
基金project supported by the National Natural Science Foundation of China (Grant Nos 60438020 and 60321003), and the Knowledge innovation program of the Chinese Academy of Sciences (Grant No KJCX2-SW-W14).
文摘The coherent exciton plays an important role in the photosynthetic primary process, and its functions are deeply dependent on the orientation arrangements of local transition dipole moments (TDMs). We theoretically and systematically study the physical property of the coherent exciton at different orientation arrangements of the local TDMs in circular light-harvesting (LH) complexes. Especially, if the orientation arrangements are different, the delocalized TDMs of the coherent excitons and the energy locations of the optically active coherent excitons (OACEs) can be obviously different, and then there are more manners to capture, store and transfer light energy in and between LH complexes. Similarly, if the orientation arrangements are altered, light absorption and radiative intensities can be converted fully between the OACEs in the upper and lower coherent exciton bands, and then the blue and red shifts of the absorption and radiative bands of the pigment molecules can occur simultaneously at some orientation arrangements. If the systems are in the vicinities of the critical orientation arrangements, the weak static disorder or small thermal excitation can destroy the coherent electronic excitations, and then the coherent exciton cannot exist any more.
文摘A simulation algorithm concerning problem B of 09 CUMCM is given. By introducing the concept of bed vector, clinic matrix, arrangement matrix and priority vector, the information about clinic, bed and arrangement will be stored and analyzed via MATLAB. By the algorithm the continuously updating of data has been simulated successfully.
文摘Living Cephalotaxus (plum yews) occurs mainly in East Asia and North of Indo-China peninsula. The study of original taxonomic literatures found that, in early days, the plum yews had ever been described as palnts of Taxus (Taxaceae). Since after the genus name Cephalotaxus Sieb. & Zucc. was firstly cited (from inedited and unpublished Flora Japonica) by Endlicher in 1842, most taxonomist thought which is the earliest time of the genus Cephalotaxus Sieb. & Zucc. was set. However, the genus Cephalotaxus Sieb. & Zucc. was formally effective and valid published by Sieb. & Zucc. in Flora Japonica in 1870 so that there exists some confusions in chronological order. Originally as a genus, Cephalotaxus was included in family Taxaceae and Neger (1907) separated Cephalotaxus from Taxaceae and set family Cephalotaxaceae. Later, Fu (1984) divided Cephalotaxus up into two sections of Cephalotaxus Sieb. & Zucc. sect. Pectinatae L. K. Fu and Cephalotaxus Sieb. & Zucc. sect. Cephalotaxus L. K. Fu on the bases of C. oliveri Masters differ significantly from other taxa of Cephalotaxus in morphological characteristics. Although the plum yews was a little genus of conifers, up to now, about 77 taxa have still been published by taxonomist in different countries or regions. Among them, C. tardiva Sieb. ex Endl. (1847), C. umbraculifera Sieb. ex Endl. (1847), C. sumatrana Miq. (1856) and C. celebica Warb. (1900) have been combined to Taxus, and C. argotaenia (Hance) Pilger (1903) has been combined to Amentotaxus. And at the same time, those taxa existing in Cephalotaxus courently which were accepted by most taxonomist in different countries was also cited in acticle. Lastly, the paper thought presently there still exists many debates about binary classification of Cephalotaxus and the nomenclature of this genus still particularly confusing. Based on some controversial problems, we also point out some taxonomically researching directions at creating some order out of the chaos.
文摘Short circuit currents of power systems are growing with an increasing rate, due to the fast development of generation and transmission systems. Current Limiting Reactor is one of the effective short circuit current limiting devices. This technique is known to be more practical than other available approaches. In this paper, proper application of CLR to HV substations is proposed, based on a comprehensive short circuit analysis of 4 well-known substation bus bar arrangements. Eventually, appropriate place and number of CLRs is recommended for each bus bar arrangement.
文摘In Africa, ageing is a phenomenon that is just beginning to reveal its shape. Most governments, including the Namibian government, recognize the fact that the number of older persons is on the increase, however, discussing it is still a distant phenomenon and family matter. This paper examines the living arrangements of older adults in Namibia, identifying the existing structure of living arrangements and the nature of family relationships of older people, as well as provides some basic descriptive information on the housing conditions in which older persons live and how they are associated with their socioeconomic and demographic factors. The analysis is based on 1991, 2001 and 2011 Namibia Population and Housing Censuses. The study concluded that living arrangements is constantly changing from extended family pattern to western nuclear family, mainly due to urbanization and decreased fertility rate. Housing conditions had notably improved in rural areas while in urban areas the conditions are affected by the mushrooming of informal settlements. There is need to encourage or conduct focused research on ageing to help coin policies based on evidence and make communities sensitive towards ageing. The study further recommends Government to encourage old people to form organizations that would in turn focus on sensitizing and help championing issues of ageing and aged persons.
文摘The proper establishment of loop-vessel countercurrent arrangement in medulla provides the basis for formation of the concentrated urine.To date,the morphogenesis of it has not been fully discovered.The present study investigated the spatial arrangement of nephron loop and vessel of developing kidneys using 3D visualization technique and immunohistochemistry for AQP-1 and NKCC2.Five-mm-thick serial paraffin sections were obtained from E14.5 and P5 kidneys and stained with hematoxylin,while 2.5-mm-thick serial epoxy sections were obtained from E17.5 and P56 kidneys and stained with toluidine blue.
文摘The possible states in the flow past two identical cylinders in tandem arrangements are investigated. The effect of the gap (L/D = 1.5, 1.75 and 2) between the two cylinders at Reynolds number (Re = 52,639) is taken into consideration. The presence of three-dimensional flow structures was observed to include notable changes to the response of the flow as result of variation of cylinder separation. A number of planes (z/h = 0.02, 0.25, 0.5 and 0.98) were taken at 20 step times of interval 0.005 s. to cover the details of flow along the cylinders. CFD FLUENT program was used to detect the flow structure. It is observed that the gap between the two cylinders affects the flow regime, i.e., there is no distinct vortex shedding downstream of the first cylinder.
文摘The main features of morphological model of industrial robots are discussed, such as support system, manipulator and gripping device. These features are presented with the alternatives for their realization as separate modules. The examples of synthesis of arrangements of industrial robots are resulted on module principle with writing of their morphological formulas.
基金financially supported by the Natural Science Foundation of Shandong Province(Grant Nos.ZR2023ME040 and ZR2022QE118)the Key Technology Research and Development Program of Shandong Province(Grant No.2023CXGC010316)+1 种基金the Natural Science Foundation of Qingdao(Grant No.23-2-1-207-zyyd-jch)the Introduction and Education Plan for Young Innovative talents in Colleges and Universities of Shandong Province(Marine Civil Engineering Materials and Structure Innovation Research Team).
文摘A vortex-induced vibration(VIV)experiment of rough risers with coupling interference effect under a side-by-side arrangement was carried out in a wave-current combined flume.The roughness of the riser was characterized by arranging different specifications of surface attachments on the surface of the riser.Rough risers with three different roughnesses were arranged side by side with smooth risers to explore the VIV response of the riser under the combined action of roughness and interference effect,and to reveal the coupling mechanism between roughness and interference effect.The experimental results show that,compared with that of a smooth riser,the VIV of a rough riser under the coupling interference effect has a wider"lock-in"region,and the displacement decreases more significantly at a high reduced velocity,which is more likely to excite higher-order modes and frequency responses.In addition,the displacement response and frequency response of the smooth riser are not significantly affected by wake interference from the rough riser,which is caused by the decrease of the wake region due to the delay of the boundary layer separation point of the rough riser.
基金supported by the Natural Science Foundation of Shandong Province(Grant Nos.ZR2023ME040 and ZR2022QE118)the Key Technology Research and Development Program of Shandong Province(Grant No.2023CXGC010316)the Natural Science Foundation of Qingdao(Grant No.23-2-1-207-zyyd-jch),and the National Natural Science Foundation of China(Grant No.51709161).
文摘In order to study the response law of vortex-induced vibration(VIV)of marine risers under the combined action of roughness and interference effects,and to reveal the coupling mechanism of roughness and interference effects on the riser,a VIV experiment of rough risers in tandem arrangement was conducted in a wave−current combined flume.The experiment characterized the risers’roughness by arranging different specifications of attachments on the surface of the risers.Three rough risers with different roughness and smooth risers were arranged in tandem arrangement,with the rough risers arranged downstream.The experimental results indicate that the suppression of the attachments on the downstream risers’vibration are more significant both in the CF and IL directions as the reduced velocity increases.For the downstream riser,the amplitude response of rough riser is more significantly weakened compared with the smooth one at high reduced velocity.For the upstream risers,changes in the roughness and spacing ratio have an impact on their‘lock-in’region.When the roughness of downstream risers is relatively large(0.1300)and the spacing between risers is small(S/D=4.0),the reduced velocity range of‘lock-in’region in the CF direction of upstream risers is obviously expanded,and the displacement in the‘lock-in’region is severer.
文摘Background: Despite overwhelming evidence for gender differences in sleep quality as well as gender-specific changes of sleep parameters with respect to habitual sleeping arrangements, studies on snorers and their bed partners have ignored the influence of individual quality of sleep as a potential co-factor. Objective: The objective of this study was to record subjective and objective sleep parameters and to analyze the effects of alternating of sleeping arrangements in snorers and their bed partners. Methods: Habitual snorers and their bed partners were recruited via newspaper articles not stating the exact purpose of the study. Both filled out a 90-day sleep diary. During this time, we recorded subjective and objective sleep parameters in the snorers and their bed partners via wrist actigraphy and sleep diaries for 14 days. For statistical analysis, we used two-sided t-tests and Spearman’s Rho. Results: The dataset included 45 snorers (11 females) and 45 bed partners (34 females) with a mean age of 47 ± 13 and 43 ± 12 years. Screening for sleep apnea yielded snoring without OSAS, mild-, moderate- and severe OSAS in 27 (60%), eight (18%), three (7%) and six (15%) snorers. PSQI total scores were significantly lower in snorers than in bed partners (4 ± 2 vs. 6 ± 4, p = 0.002). We could not find a significant correlation between subjective and objective sleep latency and efficiency. Couples who changed their sleeping arrangement were significantly younger than those who habitually slept alone or together (p = 0.01). Subjective sleep parameters of snorers or bed partners were not related to the number of consecutive nights spent either together or apart. Conclusions: Our study confirmed the weak correlation of subjective and objective sleep parameters in pairs with snoring problems. Couples changing their sleeping arrangement were the youngest among the whole group, but their separation of sleeping arrangements did not improve subjective sleep parameters.