A New Result on Regular Designs under Baseline Parameterization

The study on designs for the baseline parameterization has aroused attention in recent years. This paper focuses on two-level regular designs for the baseline parameterization. A general result on the relationship between K-aberration and word length pattern is developed.

矿业城市生态风险参数化调控规划框架——基于生态风险与景观格局关联机制

深入探讨景观格局对生态过程的影响机制,将生态风险评价结果作为国土空间布局优化的科学依据,已成为国土空间规划体系的重要内容。本文以我国最大的菱镁产业基地海城-大石桥矿区为研究对象,通过建立综合生态风险指数多元回归模型,形成基于景观格局参数的风险调控规划框架。研究结果表明:(1)采用主成分分析法形成的综合生态风险指数,能够集成多种指标特征,较好反映了综合生态风险状况;(2)以景观格局参数作为变量建立的多元回归模型,对综合生态风险指数具有较好的解释能力,通过敏感性分析能够表征出不同景观格局参数对生态风险的贡献程度;(3)基于生态风险与景观格局的关联机制研究,为空间规划途径的生态风险调控提供了量化依据。本文在景观生态学的格局-过程互馈理论下,提出了一种面向风险过程干预的空间规划设计方法,为矿业城市生态风险的防范与规避提供了一种具有较强可操作性的规划框架。

基于多源数据的黄河源区降雪比变化及其影响因素

黄河源区是黄河流域关键产流区域,对气候变化十分敏感。在气候变暖背景下,降水形态转变及其影响因素的研究依然不足。围绕这一重要科学问题,本研究基于地面气象站点观测和多源高分辨率气象数据集[China Meteorological Forcing Dataset(CMFD)、ECWMF ERA5-Land(ERA5-Land)、Multi-Source Weather(MSWX)],采用湿球温度参数化模型对1980—2015年黄河源区降水形态进行区分,并对降雪比长期变化趋势及其影响因素进行了综合研究。结果表明,1980—2015年黄河源区降水量整体呈增加趋势,降水形态向降雨转变,降雪量减少,平均降雪比呈显著下降趋势(P<0.05),四套数据源的降雪比平均下降速率为0.002 a^(-1)(P<0.05)。降雪比呈显著下降趋势(P<0.05)的格点占比分别为98.31%(ERA5-Land)、96.87%(MSWX)、67.62%(CMFD)。黄河源区中西部降雪比下降速率较快,下降速率最大的地区为玛多、达日等地。三套格点产品中CMFD能够较好地呈现降雪比变化趋势的空间差异,MSWX次之,而ERA5-Land降雪比变化趋势空间变异较小。源区降雪比与年平均气温、降水量相关性较高(P<0.05),相关系数r分别为-0.42和-0.48,亦受到西风的影响(r=-0.31,P=0.07)。研究结果有助于加深气候变暖对黄河源区水文气象过程影响的科学认识,为黄河流域区域水资源管理提供理论支撑。

东北女青年参数化鞋楦定制研究

本文基于东北女青年的脚型特征及规律,构建了一种特征点的参数化建模方法。采用三维足部扫描仪提取东北女青年18个足部特征参数,分析其脚型特征及规律,利用逆向工程技术确定286个特征点。根据脚楦关系,调整东北女青年鞋楦尺寸参数,以脚长和基宽为自变量,建立其与特征点长度方向、宽度方向、高度方向的参数关系,以构建东北女青年参数化鞋楦模型。采用该方法获得的鞋楦模型数字化程度高,便于鞋楦参数调整,对于个性化鞋楦定制具有重要意义。

基于Rhino参数化的童装结构设计

针对幼童的体型数据进行分析,提出了一种幼童服装版型参数化建模方法。采集幼童体型数据后,采用Nurbs曲线,结合东华童装原型制版规则,以身高、胸围和臀围作为关键变量,构建童装版型的几何约模型;建立三维和二维的联动关系模型,将版片导入虚拟试衣软件进行模拟验证与评估。结果表明:利用Rhino确立关键参数与版型的几何约束关系,可以快速生成个性化童装版型。使用该方法生成的纸样,与手工纸样相比最大误差不超过1 mm,童装原型压力范围在0~2.753 kpa,满足儿童着装的适体性和美观度。Rhino制版相较于传统制版和编程参数化制版方法,其速度快,操作语言简单,降低了参数化制版难度,缩短了服装企业生产周期,提高了个性化制版的精确度和制版效率。

基于Matlab的女裤参数化制版方法

为进一步提高服装CAD制版效率,满足个性化服装制版的快速响应要求,以女裤为研究对象,基于Matlab软件开发平台,设置关键参数和调节参数2种参数变量,通过参数驱动数学模型数据计算及纸样绘制程序,生成多款式且结构合理的女裤纸样,并将贝塞尔曲线拟合方法应用于参数化制版中,最后对提出的参数化制版方法进行验证。结果表明:运行参数化制版程序,可实现女裤纸样的款式变化、参数调节功能;从约束条件出发对裤装曲线进行拟合,裤装曲线能自动更新,满足新生成女裤结构合理性的要求。经参数化制版验证,提出的参数化制版方法可以满足女裤个性化自动化的服装制版要求。

Adaptive backtracking search optimization algorithm with pattern search for numerical optimization

The backtracking search optimization algorithm（BSA） is one of the most recently proposed population-based evolutionary algorithms for global optimization. Due to its memory ability and simple structure, BSA has powerful capability to find global optimal solutions. However, the algorithm is still insufficient in balancing the exploration and the exploitation. Therefore, an improved adaptive backtracking search optimization algorithm combined with modified Hooke-Jeeves pattern search is proposed for numerical global optimization. It has two main parts： the BSA is used for the exploration phase and the modified pattern search method completes the exploitation phase. In particular, a simple but effective strategy of adapting one of BSA＇s important control parameters is introduced. The proposed algorithm is compared with standard BSA, three state-of-the-art evolutionary algorithms and three superior algorithms in IEEE Congress on Evolutionary Computation 2014（IEEE CEC2014） over six widely-used benchmarks and 22 real-parameter single objective numerical optimization benchmarks in IEEE CEC2014. The results of experiment and statistical analysis demonstrate the effectiveness and efficiency of the proposed algorithm.

Geomorphologic patterns of dune networks in the Tengger Desert,China

Dune networks are widely distributed in the world＇s deserts,which include primary ridges and secondary ridges.However,they have not been sufficiently studied in a systematic manner and their origins and spatial and morphological characteristics remain unclear.To provide information on the geomorphology of dune networks,we analyze the software geomorphologic patterns of the dune networks in China＇s Tengger Desert using matrix and laboratory to process remote-sensing images.Based on analysis of image features and their layout in a topographic map,we identify two types of dune networks （square and rectangular dune networks） with different size and morphological structures in the Tengger Desert.Four important geomorphic pattern parameters,ridge length,spacing,orientation and defect density,are analyzed.The length of primary ridges of dune networks decreases from northwest of the desert to the southeast,resulting an increasing spacing and a transition from rectangular dune networks to square dune networks.Wind regime and sediment supply are responsible for the variation in pattern parameters.We use the spacing and defect density data to estimate the construction time of dune networks and found that the dune networks in the Tengger Desert formed since about 1.3 ka BP.

Comparison of two Nd:YAG laser posterior capsulotomy: cruciate pattern vs circular pattern with vitreous strand cutting

AIM： To investigate the effects and safety of neodymium： yttrium-aluminium-garnet（Nd：YAG） laser posterior capsulotomy with vitreous strand cuttingMETHODS： A total of 40 eyes of 37 patients with symptomatic posterior capsular opacity（PCO） were included in this prospective randomized study and were randomly subjected to either cruciate pattern or round pattern Nd：YAG posterior capsulotomy with vitreous strand cutting（modified round pattern）. The best corrected visual acuity（BCVA）, intraocular pressure（IOP）, refractive error, endothelial cell count（ECC）, anterior segment parameters, including anterior chamber depth（ACD） and anterior chamber angle（ACA） were measured before and 1 mo after the laser posterior capsulotomy. RESULTS： In both groups, the BCVA improved significantly（P〈0.001 for the modified round pattern group, P=0.001 for the cruciate pattern group）; the IOP and ECC did not significantly change. The ACD significantly decreased（P〈0.001 for both） and the ACA significantly increased（P=0.001 for the modified round pattern group and P=0.034 for the cruciate group）. The extent of changes in these parameters was not significantly different between the groups.CONCLUSION： Modified round pattern Nd：YAG laser posterior capsulotomy is an effective and safe method for the treatment of PCO. This method significantly changes the ACD and ACA, but the change in refraction is not significant. Modified round pattern Nd：YAG laser posterior capsulotomy can be considered a good alternative procedure in patients with symptomatic PCO.

A new damping ratio identification method based on pattern search

In order to improve the effectiveness of traditional time domain identification methods in identifying damping ratios, a new damping ratio identification method based on pattern search is proposed by fluctuating the reliable natural frequency obtained through traditional time domain identification methods by about 10% to build the boundary conditions, using all the initial identification results to establish the free decay response of the system, and using the pattern search method to correct the initial identification results with the residual sum of squares between the free decay response and the actually measured free-decay signal as the objective function. The proposed method deals with the actually measured free-decay signal with curve fitting and avoids enlarging the identified error caused by intermediate conversion, so it can effectively improve the identified accuracy of damping ratios. Simulations for a room-sized vibration isolation foundation show that the relative errors of analyzed three damping ratios are down to 1.05%, 1.51% and 3.7% by the proposed method from 8.42%, 5.85% and 8.5% by STD method when the noise level is 10%.

Hollow hexagonal pattern with surface discharges in a？dielectric barrier discharge

The hollow hexagonal pattern involved in surface discharges is firstly investigated in a？dielectric barrier discharge system. The spatiotemporal structures of the pattern are studied using an intensified charge-coupled device and photomultiplier. Instantaneous images taken by an intensified charge-coupled device and optical correlation measurements show that the surface discharges are induced by volume discharges. The optical signals indicate that the discharge filaments constituting the hexagonal frame discharge randomly at the first current pulse or the second pulse, once？or twice. There is no？interleaving of several sub-lattices, which indicates that the ‘memory＇ effect is no longer in force due to surface discharges. By using the emission spectrum method, both the molecule vibration temperature？and electron density of the surface discharges are larger than that of the volume discharges.

速滑服装版型参数化模型构建方法

速滑服装作为高性能的运动装备,不仅利于运动员技术动作的发挥,同时可以有效保护运动员的安全。为实现速滑服装的个性化定制,需要针对运动员体型构建基于参数化的建模方法。提出了一种速滑服装版型参数化模型构建方法,根据人体体型特征及速滑服装结构特点,明确体型关键点与版型关键点的对位关系;基于人体三维模型提取速滑服装的各部件衣片三维模型,利用三维网格展平技术,获取对应衣片的二维版片形状,使用参数定义二维版片边缘曲线特征点,并建立版型参数与体型参数的关系模型,实现速滑服版型参数化模型构建;利用3D虚拟软件进行虚拟试衣验证并对参数化生成的版型进行比较分析。结果表明:参数化模型方法生成的速滑服装具有较好的合体度,为速滑服装个性化定制应用提供技术参考,对于实现速滑服装个性化定制具有重要意义和实用价值。

龟背纹的参数化设计研究

龟背纹是具有几何趣味的经典传统纹样,极富秩序性、数理性,但以龟背纹为代表的传统纹样面临文化内涵认知不足、现代化转化不佳以及设计成本过高的问题。文章为解决以上问题,现提取龟背纹的纹样特征,再通过Grasshopper软件进行龟背纹的参数化设计。该方法可通过半径、边数、曲率、颜色值的修改,在短时间内生成大批量纹样,以完成龟背纹的多样化设计方案,提高设计效率,并促进传统文化与数字时代的结合。

凸肚体男衬衫制版参数化建模方法

互联网背景下服装个性化定制需求日益增长,这对服装数字化精准制版提出新的要求,尤其是对特殊体型合体服装的制版和参数化自动化版型的生成具有重要意义。本文提出一种针对凸肚特殊体型的男衬衫个性化版型参数化建模与生成方法:通过典型凸肚体型人体三维模型的特征提取构建衬衣原型版;利用基于质点弹簧的三维网格展平算法生成满足能量最小化约束条件的二维原型版;结合衬衫制版的规则在二维原型基础上建立衬衫版型曲线的参数化表示模型,并建立体型参数的联动关系模型;通过Style 3D虚拟试衣软件进行模拟试穿验证。结果表明:在传统衬衣参数化制版基础上,增加肚围这一参数,可实现输入用户体型参数生成个性化衬衫版型纸样图形。该方法针对凸肚体型能够快速生成较为合体的个性化衬衫纸样,减少了个性化定制制版的工作量,提高了个性化制版的精确度和制版效率。

不同形状截割头截齿排列的参数化设计

通过对螺旋升角的定义,建立截割头包络面螺旋线的数学模型,提出等螺旋升角的截齿排列理论,给出不同形状截割头包络面母线的截齿空间位置模型。通过编制程序进行实例设计,获得两种不同形状的截割头及其截齿的排列和切屑图。结果表明,该模型设计的截齿排列分布均匀,截线距从截割头大端向小端递减,各截齿的切削面积均匀,截齿受力状况良好,满足截齿排列的要求,为截割头设计及截齿排列的参数化奠定了基础。

基于模式匹配的参数化尺寸标注机理研究

研究了一种新的参数化尺寸标注机理，提出了基于模式匹配及其推理的方法．该方法借助于ＡｕｔｏＣＡＤ的尺寸标注功能及其存储格式，将国家机械制图标准所规定的尺寸标注模式与其相匹配，在归纳ＡｕｔｏＣＡＤ 和国家标准的各种尺寸标注模式的基础上，设计了一个新的参数化尺寸标注系统，实现了智能化尺寸标注功能，使其能够准确地标注国标所规定的各种尺寸标注模式．

通用测试平台的讨论

文章着重从结构、管理、工具支持、测试人员的使用及平台的安全性等几个方面对如何建立可升级数化的通用测试平台提出一种解决方案,并努力使之具有普适性,以期指导更多的工程实践。

参数化尺寸标注系统开发技术的研究

提出了一种开发参数化尺寸标注系统的新方法，即基于模式匹配及其推理的方法．该方法借助于ＡｕｔｏＣＡＤ的尺寸标注功能及其存储格式，将国家机械制图标准所规定的尺寸标注模式与其相匹配，在归纳ＡｕｔｏＣＡＤ和国家标准的各种尺寸标注模式的基础上，设计了一个新的参数化尺寸标注系统，实现了智能化尺寸标注功能。

轮胎胎面花纹的参数化设计

以12.00R20全钢载重子午线轮胎某一类型胎面花纹为例,利用三维软件CATIA探讨轮胎胎面花纹的参数化设计方法。通过提取胎面花纹的主要特征参数建立花纹块模型,同时建立花纹块的主要特征参数与相应实体之间的关联关系,利用Excel实现花纹块的参数化,结合CATIA软件建立胎面花纹块数据库,实现轮胎胎面花纹的三维参数化设计。

基于设计模式的数据库出版系统的框架模型

随着个性化印刷 ,跨媒体出版的出现和广泛应用 ,数据库出版具有了一些新的特点 .传统的数据库出版已经无法满足这些新的需求 .在分析了数据库出版系统的难点和问题后 ,提出了基于设计模式的以模板为基础的数据库出版系统的框架模型 .该模型将设计模式中的 Com posite模式和 Prototype模式创造性地应用到了数据库出版系统中 ,引入了参数模板、界面组块和排版组块的概念 ,实现了包括输出页码 ,目录和索引在内的自动化出版 .实践证明本模型具有很高的时效性 。