As a kind of natural fiber,ramie fiber has distinctive advantages in textile application,but the application is limited due to the traditional degumming mode.Compared with the traditional degumming process,the microbi...As a kind of natural fiber,ramie fiber has distinctive advantages in textile application,but the application is limited due to the traditional degumming mode.Compared with the traditional degumming process,the microbial degumming process has many advantages.To obtain the optimal conditions for degumming ramie with Bacillus subtilis DZ_(5)(BS DZ_(5)),a combined statistical approach of orthogonal array design(OAD)and response surface methodology(RSM)was used.The influences of initial pH of the bacteria medium,culture temperature,shaking speed,degumming time and inoculum size on submerged fermentation degumming were evaluated by using fractional factorial design.The main factors in the analysis were culture temperature,shaking speed and initial pH.The residual gum mass fraction was used as the optimization index,and the optimal conditions for degumming were determined by central composite design and RSM.Thus with only a limited number of experiments,an optimal ramie microbial degumming condition was found as the culture temperature of 40℃,the initial pH in the culture medium of 8.5,the shaking speed of 205 r/min,the degumming time of 96 h and the inoculum size of 5%.After microbial degumming of ramie under the optimal conditions,there was only 10.6%residual gum by mass in the fiber.In addition,the effective degumming of BS DZ_(5)was also confirmed by a scanning electron microscope(SEM).展开更多
The separation of enzymatic hydrolysis products of yeast RNA by ion-pair HPLC was studied.A modified chromatographic response function(MCRF) was proposed to appraise the effectiveness of chromatographic separation.T...The separation of enzymatic hydrolysis products of yeast RNA by ion-pair HPLC was studied.A modified chromatographic response function(MCRF) was proposed to appraise the effectiveness of chromatographic separation.This function takes the number of peaks,resolution and the retention time of the last peak into consideration.It shows advantages for optimization of HPLC separation of complex mixtures.An orthogonal array design was used to separate the hydrolysate of yeast RNA and the optimal chromatographic conditions were obtained.展开更多
In this study,a moored array optimization tool(MAOT)was developed and applied to the South China Sea(SCS)with a focus on three-dimensional temperature and salinity observations.Application of the MAOT involves two ste...In this study,a moored array optimization tool(MAOT)was developed and applied to the South China Sea(SCS)with a focus on three-dimensional temperature and salinity observations.Application of the MAOT involves two steps:(1)deriving a set of optimal arrays that are independent of each other for different variables at different depths based on an empirical orthogonal function method,and(2)consolidating these arrays using a K-center clustering algorithm.Compared with the assumed initial array consisting of 17 mooring sites located on a 3°×3°horizontal grid,the consolidated array improved the observing ability for three-dimensional temperature and salinity in the SCS with optimization efficiencies of 19.03%and 21.38%,respectively.Experiments with an increased number of moored sites showed that the most cost-effective option is a total of 20 moorings,improving the observing ability with optimization efficiencies up to 26.54%for temperature and 27.25%for salinity.The design of an objective array relies on the ocean phenomenon of interest and its spatial and temporal scales.In this study,we focus on basin-scale variations in temperature and salinity in the SCS,and thus our consolidated array may not well resolve mesoscale processes.The MAOT can be extended to include other variables and multi-scale variability and can be applied to other regions.展开更多
Objective To establish a rapid and effective supercritical fluid extraction(SFE) and rapid resolution liquid chromatography method coupled with diode-array detector(RRLC-DAD) to quantify the chromones in a species...Objective To establish a rapid and effective supercritical fluid extraction(SFE) and rapid resolution liquid chromatography method coupled with diode-array detector(RRLC-DAD) to quantify the chromones in a species. Methods The effects of four parameters including ethanol concentration(50%-90%), pressure(25-45 MPa), temperature(40-60 ℃), and time(30-90 min) on the chromones yields, namely prim-O-glucosylcimifugin, cimifugin, 5-O-methylvisammioside, and sec-O-glucosylhamaudol, were investigated using SFE system with orthogonal array design(OAD). Furthermore, the extracts were analyzed using rapid resolution liquid chromatography coupled with diode-array detector(RRLC-DAD) system to confirm the results. Results Under the optimized conditions, i.e., 35 MPa of pressure, 60 ℃ of temperature, 70% ethanol, and 60 min of time, the yields of prim-O-glucosylcimifugin, cimifugin, 5-O-methylvisammioside, sec-O-glucosylhamaudol, and total chromones were 3.514, 0.132, 6.242, 0.342, and 10.231 mg/g, respectively. In comparison with ultrasonic assisted extraction(UAE), SFE was able to yield a 20.7% increase in the total chromones from Saposhnikoviae Radix. Conclusion SFE is an alternative and promising method to extract chromones from this species, and the established RRLC-DAD method could serve as a rapid and effective method for the identification of chromones from Saposhnikoviae Radix.展开更多
The theory of uniform design has received increasing interest because of its wide application in the field of computer experiments.The generalized discrete discrepancy is proposed to evaluate the uniformity of the mix...The theory of uniform design has received increasing interest because of its wide application in the field of computer experiments.The generalized discrete discrepancy is proposed to evaluate the uniformity of the mixed-level factorial design.In this paper,the authors give a lower bound of the generalized discrete discrepancy and provide some construction methods of optimal mixed-level uniform designs which can achieve this lower bound.These methods are all deterministic construction methods which can avoid the complexity of stochastic algorithms.Both saturated mixed-level uniform designs and supersaturated mixed-level uniform designs can be obtained with these methods.Moreover,the resulting designs are also χ^(2)-optimal and minimum moment aberration designs.展开更多
Pairwise key establishment is a fundamental security service in sensor networks; it enables sensor nodes to communicate securely with each other using cryptographic techniques. In order to ensure this security, many a...Pairwise key establishment is a fundamental security service in sensor networks; it enables sensor nodes to communicate securely with each other using cryptographic techniques. In order to ensure this security, many approaches have been proposed recently. One of them is to use key predistribution schemes (KPSs) by means of combinatorial designs. In this paper, we use the Bush's construction of orthogonal arrays to present a class of key predistribution schemes for distributed sensor networks. The secure connectivity and resilience of the resulting sensor network are analyzed. This KPS constructed in our paper has some better properties than those of the existing schemes.展开更多
The influence of Co, W and Ti on stress-rupture lives of a Ni-Cr-AI-Mo-Ta-Co-W-Ti single crystal nickel-base superalloy has been investigated using a L9 (34) orthogonal array design (OAD) by statistical analysis. ...The influence of Co, W and Ti on stress-rupture lives of a Ni-Cr-AI-Mo-Ta-Co-W-Ti single crystal nickel-base superalloy has been investigated using a L9 (34) orthogonal array design (OAD) by statistical analysis. At a selected composition range, Ti content was the most important factor to the effect of the stress-rupture lives and then followed by Co content. W content had the minimum effect on stress-rupture lives. The optimal alloy should contain 10 wt pct Co, 8 wt pct W and zero Ti. The optimized alloy also had good microstructural stability during thermal exposure at 870℃ for 500 h.展开更多
The purpose of this paper is to survey the construction of orthogonal arrays of strength two by using difference sets. Some methods for constructing difference set D(2p.2p,p,2), where p is a prime or a prime power, ar...The purpose of this paper is to survey the construction of orthogonal arrays of strength two by using difference sets. Some methods for constructing difference set D(2p.2p,p,2), where p is a prime or a prime power, are given. It is shown that the Kronecker sum of a difference set D(λ1p, k1, p, 2) and an orthogonal array(λ2p2, k2, p, 2) leads to another orthogonal array (λ1λ2p3 .k1k2+1 ,p, 2). This enables us to construct orthogonal arrays[2p(n+1)、1+2(p+p2 +…+pn),p,2],[4p(n+2),1+2p+4(p2+p3+…+p(n+1)),p, 2],and [8p(n+3),1+2P+4p2+8(p3+p4+…+p(n+2)),p,2]where p is a prime or a prime power.展开更多
ORTHOGONAL arrays (OAs) have important applications to many fields. A lot of OAs and their construction methods have been introduced in the experimental design literature (for example, Box, Hunter and Dey). These OAs ...ORTHOGONAL arrays (OAs) have important applications to many fields. A lot of OAs and their construction methods have been introduced in the experimental design literature (for example, Box, Hunter and Dey). These OAs are used for an experimenter to choose in practice.展开更多
The orthogonal Latin hypercube design and its relaxation,and column-orthogonal design,are two kinds of orthogonal designs for computer experiments.However,they usually do not achieve maximum stratifications in multi-d...The orthogonal Latin hypercube design and its relaxation,and column-orthogonal design,are two kinds of orthogonal designs for computer experiments.However,they usually do not achieve maximum stratifications in multi-dimensional margins.In this paper,we propose some methods to construct column-orthogonal designs with multi-dimensional stratifications by rotating symmetric and asymmetric orthogonal arrays.The newly constructed column-orthogonal designs ensure that the estimates of all linear effects are uncorrelated with each other and even uncorrelated with the estimates of all second-order effects(quadratic effects and bilinear effects)when the rotated orthogonal arrays have strength larger than two.Besides orthogonality,the resulting designs also preserve better space-filling properties than those constructed by using the existing methods.In addition,we provide a method to construct a new class of orthogonal Latin hypercube designs with multi-dimensional stratifications by rotating regular factorial designs.Some newly constructed orthogonal Latin hypercube designs are tabulated for practical use.展开更多
This paper is concerned with the uniformity of a certain kind of resolvable incomplete block (RIB for simplicity) design which is called the PRIB design here. A sufficient and necessary condition is obtained, under wh...This paper is concerned with the uniformity of a certain kind of resolvable incomplete block (RIB for simplicity) design which is called the PRIB design here. A sufficient and necessary condition is obtained, under which a PRIB design is the most uniform in the sense of a discrete discrepancy measure, and the uniform PRIB design is shown to be connected. A construction method for such designs via a kind of U-type designs is proposed, and an existence result of these designs is given. This method sets up an important bridge between PRIB designs and U-type designs.展开更多
This article considers the problem of selecting two-level designs under the baseline parameterisation when some two-factor interactions are important.We propose a minimum aberration criterion,which minimises the bias ...This article considers the problem of selecting two-level designs under the baseline parameterisation when some two-factor interactions are important.We propose a minimum aberration criterion,which minimises the bias caused by the non-negligible effects.Using this criterion,a class of optimal designs can be further distinguished from one another,and we present an algorithm to find the minimum aberration designs among the D-optimal designs.Sixteen-run and twenty-run designs are summarised for practical use.展开更多
In statistical planning of experiments, super-simple designs are the ones providing samples with maximum intersection as small as possible. Super- simple group divisible designs are useful in constructing other types ...In statistical planning of experiments, super-simple designs are the ones providing samples with maximum intersection as small as possible. Super- simple group divisible designs are useful in constructing other types of super- simple designs which can be applied to codes and designs. In this article, the existence of a super-simple (5, 4)-GDD of group type gU is investigated and it is shown that such a design exists if and only if u ≥ 5, g(u - 2) ≥ 12, and u(u - 1)g^2≡ 0 (mod 5) with some possible exceptions.展开更多
基金National Natural Science Foundation of China(No.51863020)。
文摘As a kind of natural fiber,ramie fiber has distinctive advantages in textile application,but the application is limited due to the traditional degumming mode.Compared with the traditional degumming process,the microbial degumming process has many advantages.To obtain the optimal conditions for degumming ramie with Bacillus subtilis DZ_(5)(BS DZ_(5)),a combined statistical approach of orthogonal array design(OAD)and response surface methodology(RSM)was used.The influences of initial pH of the bacteria medium,culture temperature,shaking speed,degumming time and inoculum size on submerged fermentation degumming were evaluated by using fractional factorial design.The main factors in the analysis were culture temperature,shaking speed and initial pH.The residual gum mass fraction was used as the optimization index,and the optimal conditions for degumming were determined by central composite design and RSM.Thus with only a limited number of experiments,an optimal ramie microbial degumming condition was found as the culture temperature of 40℃,the initial pH in the culture medium of 8.5,the shaking speed of 205 r/min,the degumming time of 96 h and the inoculum size of 5%.After microbial degumming of ramie under the optimal conditions,there was only 10.6%residual gum by mass in the fiber.In addition,the effective degumming of BS DZ_(5)was also confirmed by a scanning electron microscope(SEM).
文摘The separation of enzymatic hydrolysis products of yeast RNA by ion-pair HPLC was studied.A modified chromatographic response function(MCRF) was proposed to appraise the effectiveness of chromatographic separation.This function takes the number of peaks,resolution and the retention time of the last peak into consideration.It shows advantages for optimization of HPLC separation of complex mixtures.An orthogonal array design was used to separate the hydrolysate of yeast RNA and the optimal chromatographic conditions were obtained.
基金The National Key Research and Development Program of China under contract No.2019YFC1408400the National Natural Science Foundation of China under contract No.41876029.
文摘In this study,a moored array optimization tool(MAOT)was developed and applied to the South China Sea(SCS)with a focus on three-dimensional temperature and salinity observations.Application of the MAOT involves two steps:(1)deriving a set of optimal arrays that are independent of each other for different variables at different depths based on an empirical orthogonal function method,and(2)consolidating these arrays using a K-center clustering algorithm.Compared with the assumed initial array consisting of 17 mooring sites located on a 3°×3°horizontal grid,the consolidated array improved the observing ability for three-dimensional temperature and salinity in the SCS with optimization efficiencies of 19.03%and 21.38%,respectively.Experiments with an increased number of moored sites showed that the most cost-effective option is a total of 20 moorings,improving the observing ability with optimization efficiencies up to 26.54%for temperature and 27.25%for salinity.The design of an objective array relies on the ocean phenomenon of interest and its spatial and temporal scales.In this study,we focus on basin-scale variations in temperature and salinity in the SCS,and thus our consolidated array may not well resolve mesoscale processes.The MAOT can be extended to include other variables and multi-scale variability and can be applied to other regions.
基金National Natural Science Foundation of China(Grant No.31300270)the Technology Key Project of Jilin Province(Grant No.20130522048JH)the twelfth five-year science and technology plan project of Jilin Education Department(2015205)
文摘Objective To establish a rapid and effective supercritical fluid extraction(SFE) and rapid resolution liquid chromatography method coupled with diode-array detector(RRLC-DAD) to quantify the chromones in a species. Methods The effects of four parameters including ethanol concentration(50%-90%), pressure(25-45 MPa), temperature(40-60 ℃), and time(30-90 min) on the chromones yields, namely prim-O-glucosylcimifugin, cimifugin, 5-O-methylvisammioside, and sec-O-glucosylhamaudol, were investigated using SFE system with orthogonal array design(OAD). Furthermore, the extracts were analyzed using rapid resolution liquid chromatography coupled with diode-array detector(RRLC-DAD) system to confirm the results. Results Under the optimized conditions, i.e., 35 MPa of pressure, 60 ℃ of temperature, 70% ethanol, and 60 min of time, the yields of prim-O-glucosylcimifugin, cimifugin, 5-O-methylvisammioside, sec-O-glucosylhamaudol, and total chromones were 3.514, 0.132, 6.242, 0.342, and 10.231 mg/g, respectively. In comparison with ultrasonic assisted extraction(UAE), SFE was able to yield a 20.7% increase in the total chromones from Saposhnikoviae Radix. Conclusion SFE is an alternative and promising method to extract chromones from this species, and the established RRLC-DAD method could serve as a rapid and effective method for the identification of chromones from Saposhnikoviae Radix.
基金supported by the National Natural Science Foundation of China under Grant Nos.12131001,12226343,12371260,and 12371261National Ten Thousand Talents Program of Chinathe 111 Project under Grant No.B20016.
文摘The theory of uniform design has received increasing interest because of its wide application in the field of computer experiments.The generalized discrete discrepancy is proposed to evaluate the uniformity of the mixed-level factorial design.In this paper,the authors give a lower bound of the generalized discrete discrepancy and provide some construction methods of optimal mixed-level uniform designs which can achieve this lower bound.These methods are all deterministic construction methods which can avoid the complexity of stochastic algorithms.Both saturated mixed-level uniform designs and supersaturated mixed-level uniform designs can be obtained with these methods.Moreover,the resulting designs are also χ^(2)-optimal and minimum moment aberration designs.
基金supported by the National Natural Science Foundation of China under Grant Nos. 60473017, 90604034and 10771078.
文摘Pairwise key establishment is a fundamental security service in sensor networks; it enables sensor nodes to communicate securely with each other using cryptographic techniques. In order to ensure this security, many approaches have been proposed recently. One of them is to use key predistribution schemes (KPSs) by means of combinatorial designs. In this paper, we use the Bush's construction of orthogonal arrays to present a class of key predistribution schemes for distributed sensor networks. The secure connectivity and resilience of the resulting sensor network are analyzed. This KPS constructed in our paper has some better properties than those of the existing schemes.
基金This work was supported by the National Natural Science Foundation of China under grand No.50474058.
文摘The influence of Co, W and Ti on stress-rupture lives of a Ni-Cr-AI-Mo-Ta-Co-W-Ti single crystal nickel-base superalloy has been investigated using a L9 (34) orthogonal array design (OAD) by statistical analysis. At a selected composition range, Ti content was the most important factor to the effect of the stress-rupture lives and then followed by Co content. W content had the minimum effect on stress-rupture lives. The optimal alloy should contain 10 wt pct Co, 8 wt pct W and zero Ti. The optimized alloy also had good microstructural stability during thermal exposure at 870℃ for 500 h.
文摘The purpose of this paper is to survey the construction of orthogonal arrays of strength two by using difference sets. Some methods for constructing difference set D(2p.2p,p,2), where p is a prime or a prime power, are given. It is shown that the Kronecker sum of a difference set D(λ1p, k1, p, 2) and an orthogonal array(λ2p2, k2, p, 2) leads to another orthogonal array (λ1λ2p3 .k1k2+1 ,p, 2). This enables us to construct orthogonal arrays[2p(n+1)、1+2(p+p2 +…+pn),p,2],[4p(n+2),1+2p+4(p2+p3+…+p(n+1)),p, 2],and [8p(n+3),1+2P+4p2+8(p3+p4+…+p(n+2)),p,2]where p is a prime or a prime power.
文摘ORTHOGONAL arrays (OAs) have important applications to many fields. A lot of OAs and their construction methods have been introduced in the experimental design literature (for example, Box, Hunter and Dey). These OAs are used for an experimenter to choose in practice.
基金supported by National Natural Science Foundation of China(Grant Nos.11871033,11771220,11671386,11771219 and 11971345)National Ten Thousand Talents Program+2 种基金Tianjin Development Program for Innovation and EntrepreneurshipTianjin“131”Talents Programthe Postdoctoral Science Foundation Funded Project of China(Grant No.2017M611147)。
文摘The orthogonal Latin hypercube design and its relaxation,and column-orthogonal design,are two kinds of orthogonal designs for computer experiments.However,they usually do not achieve maximum stratifications in multi-dimensional margins.In this paper,we propose some methods to construct column-orthogonal designs with multi-dimensional stratifications by rotating symmetric and asymmetric orthogonal arrays.The newly constructed column-orthogonal designs ensure that the estimates of all linear effects are uncorrelated with each other and even uncorrelated with the estimates of all second-order effects(quadratic effects and bilinear effects)when the rotated orthogonal arrays have strength larger than two.Besides orthogonality,the resulting designs also preserve better space-filling properties than those constructed by using the existing methods.In addition,we provide a method to construct a new class of orthogonal Latin hypercube designs with multi-dimensional stratifications by rotating regular factorial designs.Some newly constructed orthogonal Latin hypercube designs are tabulated for practical use.
基金This work was partially supported by the Hong Kong RGC grant RGC/HKBU 2044/02Pthe National Natural Science Foundation of China(Grants No.10171051&10301015)the Outstanding Scholar Program of Nankai University.
文摘This paper is concerned with the uniformity of a certain kind of resolvable incomplete block (RIB for simplicity) design which is called the PRIB design here. A sufficient and necessary condition is obtained, under which a PRIB design is the most uniform in the sense of a discrete discrepancy measure, and the uniform PRIB design is shown to be connected. A construction method for such designs via a kind of U-type designs is proposed, and an existence result of these designs is given. This method sets up an important bridge between PRIB designs and U-type designs.
基金supported by Natural Sciences and Engineering Research Council of Canada[Discovery Grant].
文摘This article considers the problem of selecting two-level designs under the baseline parameterisation when some two-factor interactions are important.We propose a minimum aberration criterion,which minimises the bias caused by the non-negligible effects.Using this criterion,a class of optimal designs can be further distinguished from one another,and we present an algorithm to find the minimum aberration designs among the D-optimal designs.Sixteen-run and twenty-run designs are summarised for practical use.
基金Acknowledgements This work was supported by the National Natural Science Foundation of China (Grant Nos. 11371121, 11371308, 11201114, 11301457).
文摘In statistical planning of experiments, super-simple designs are the ones providing samples with maximum intersection as small as possible. Super- simple group divisible designs are useful in constructing other types of super- simple designs which can be applied to codes and designs. In this article, the existence of a super-simple (5, 4)-GDD of group type gU is investigated and it is shown that such a design exists if and only if u ≥ 5, g(u - 2) ≥ 12, and u(u - 1)g^2≡ 0 (mod 5) with some possible exceptions.