图形宣传：2001～2012数码时代国际海报展选辑

“当今社会已不再是大众通过单一媒介渠道来获取信息的时代，我们现在有多种来源、多种渠道和多样化受众。每个参与者都可以成为信息发送者和接收者．这只需一台电脑和互联网连接就可做到，而无需花费大量资金建立一个电视台或一份报纸。如今，许多政治图形设计都可在电脑上完成，并借助互联网传送。随着宽带连接的发展，一张全彩色的海报完全可以做成数字文件，通过电子邮件来发送，或从网站下载，然后由接收者印制所需份数，或简单地以数字格式转发”。——节选自C01in Moore所著《宣传画：服务于社会与政治变革的艺术史》（伦敦A＋C BooKs2011年出版）     

Liquid-Metal Synthesized Ultrathin SnS Layers for High-Performance Broadband Photodetectors

Atomically thin materials face an ongoing challenge of scalability, hampering practical deployment despite their fascinating properties. Tin monosulfide (SnS), a low-cost, naturally abundant layered material with a tunable bandgap, displays properties of superior carrier mobility and large absorption coefficient at atomic thicknesses, making it attractive for electronics and optoelectronics. However, the lack of successful synthesis techniques to prepare large-area and stoichiometric atomically thin SnS layers (mainly due to the strong interlayer interactions) has prevented exploration of these properties for versatile applications. Here, SnS layers are printed with thicknesses varying from a single unit cell (0.8 nm) to multiple stacked unit cells (≈1.8 nm) synthesized from metallic liquid tin, with lateral dimensions on the millimeter scale. It is reveal that these large-area SnS layers exhibit a broadband spectral response ranging from deep-ultraviolet (UV) to near-infrared (NIR) wavelengths (i.e., 280–850 nm) with fast photodetection capabilities. For single-unit-cell-thick layered SnS, the photodetectors show upto three orders of magnitude higher responsivity (927 A W⁻¹) than commercial photodetectors at a room-temperature operating wavelength of 660 nm. This study opens a new pathway to synthesize reproduceable nanosheets of large lateral sizes for broadband, high-performance photodetectors. It also provides important technological implications for scalable applications in integrated optoelectronic circuits, sensing, and biomedical imaging.     

3D‐Printed,All‐in‐One Evaporator for High‐Efficiency Solar Steam Generation under 1 Sun Illumination

Using solar energy to generate steam is a clean and sustainable approach to addressing the issue of water shortage. The current challenge for solar steam generation is to develop easy‐to‐manufacture and scalable methods which can convert solar irradiation into exploitable thermal energy with high efficiency. Although various material and structure designs have been reported, high efficiency in solar steam generation usually can be achieved only at concentrated solar illumination. For the first time, 3D printing to construct an all‐in‐one evaporator with a concave structure for high‐efficiency solar steam generation under 1 sun illumination is used. The solar‐steam‐generation device has a high porosity (97.3%) and efficient broadband solar absorption (>97%). The 3D‐printed porous evaporator with intrinsic low thermal conductivity enables heat localization and effectively alleviates thermal dissipation to the bulk water. As a result, the 3D‐printed evaporator has a high solar steam efficiency of 85.6% under 1 sun illumination (1 kW m^?2), which is among the best compared with other reported evaporators. The all‐in‐one structure design using the advanced 3D printing fabrication technique offers a new approach to solar energy harvesting for high‐efficiency steam generation.     

鲁南民间彩印花布设计因子的提取与应用

目的 鲁南民间彩印花布是具有浓郁地方特色的手工技艺,通过探索鲁南民间彩印花布在文创产品中的设计方法,拓宽非遗的发展路径。方法 以鲁南民间彩印花布为研究对象,通过实地调查和文献资料整理,以图文结合的方法对鲁南民间彩印花布的图案、布局、色彩等显性因子,以及设计特征、语义内涵等隐性因子进行梳理和分析。依据CGM模型对鲁南民间彩印花布的设计因子进行提取与推演,将推演出的新图案与文创产品相结合,探讨二者的相容性。结论 鲁南民间彩印花布具有极强的装饰意蕴,通过构建CGM模型规则推演出具有鲁南民间彩印花布基因的创新图案具有较强的可行性。该方法不仅为具有主题意蕴的传统图案再设计拓展了思路,而且为鲁南民间彩印花布开拓应用途径提供了参考。     

Ductility of 3D printed concrete reinforced with short straight steel fibers

ABSTRACT

With the number of 3D printed concrete structures rapidly increasing, the demand for concepts that allow for robust and ductile printed objects becomes increasingly pressing. An obvious solution strategy is the inclusion of fibers in the printed material. In this study, the effect of adding short straight steel fibers on the failure behaviour of Weber 3D 115-1 print mortar has been studied through several CMOD tests on cast and printed concrete, on different scales. The experiments have also been simulated numerically. The research has shown that the fibers cause an important increase in flexural strength, and eliminate the strength difference between cast and printed concrete that exists without fibers. The post-peak behaviour, nevertheless, has to be characterised as strongly strain-softening. In the printed specimens, a strong fiber orientation in the direction of the filament occurs. However, this has no notable effect on the performance in the tested direction: cast and printed concrete with fibers behave similarly in the CMOD test. For the key parameters, no scale effect was found for the specimens with fibers, contrary to the ones without. Numerical modelling of the test by using the Concrete Damage Plasticity material model of Abaqus, with a Thorenfeldt-based constitutive law in compression and a customised constitutive law in tension, results in a reasonable fit with the experimental results.     

Time gap effect on bond strength of 3D-printed concrete

An advancing technology that combines the concrete extrusion with a motion control to create structures with complex geometrical shapes without the need for formwork is known as 3D concrete printing. Since this technique prints layer by layer, the time taken to reach the same position in the subsequent layer is important as it will create an anisotropic property that has a weaker tensile strength at the bond interface of the two printed filaments. Through rheological measurement, which reveals the material deformation and flow behaviour, it is possible to examine the material structural build-up due to time-gap effect by measuring at different time delay. This paper focuses on investigating the time-gap effect on the printed filament with rheological and observation at macroscopic-scale to understand the material behaviour of the initial and subsequent printed layer during its fresh phase. Rheological experiment findings reveal that the tensile strength of the printed specimen is correlated to the material modulus at the initial layer.     

广彩瓷的色彩演变及设计应用研究

目的以广彩瓷色彩为研究切入点,为其设计应用提供新思路,以期对广彩瓷的传承发展起到抛砖引玉的作用。方法梳理广彩瓷色彩的演变过程,分析不同时期的色彩特征及赋色技法,结合包装设计、服饰设计、装饰艺术设计实例,摸索出广彩瓷的色彩规律及精髓加以创造设计。结论广彩瓷兼容并蓄的独特美感,曾经在中西贸易中发挥过巨大作用,促进了中西精神文化与物质文明的交流碰撞。基于广彩瓷的色彩研究,深入领会其色彩文化内涵并加以提炼,巧妙运用于当代设计,不仅可以推动广彩瓷行业的传承发展,更可为现代设计增添无穷魅力及全球性文化附加值。     

Optical BEAMTAP beam-forming and jammer-nulling system for broadband phased-array antennas

We present an approach to receive-mode broadband beam forming and jammer nulling for large adaptive antenna arrays as well as its efficient and compact optical implementation. This broadband efficient adaptive method for true-time-delay array processing (BEAMTAP) algorithm decreases the number of tapped delay lines required for processing an N-element phased-array antenna from N to only 2, producing an enormous savings in delay-line hardware (especially for large broadband arrays) while still providing the full NM degrees of freedom of a conventional N-element time-delay-and-sum beam former that requires N tapped delay lines with M taps each. This allows the system to adapt fully and optimally to an arbitrarily complex spatiotemporal signal environment that can contain broadband signals of interest, as well as interference sources and narrow-band and broadband jammers-all of which can arrive from arbitrary angles onto an arbitrarily shaped array-thus enabling a variety of applications in radar, sonar, and communication. This algorithm is an excellent match with the capabilities of radio frequency (rf) photonic systems, as it uses a coherent optically modulated fiber-optic feed network, gratings in a photorefractive crystal as adaptive weights, a traveling-wave detector for generating time delay, and an acousto-optic device to control weight adaptation. Because the number of available adaptive coefficients in a photorefractive crystal is as large as 10(9), these photonic systems can adaptively control arbitrarily large one- or two-dimensional antenna arrays that are well beyond the capabilities of conventional rf and real-time digital signal processing techniques or alternative photonic techniques.     

宋刻本版面范式设计的用尺标准

目的 探索宋代刻书中心刻本版面范式设计的基本用尺标准,进而分析宋代雕版印刷规模化生产的通用性设计规制。方法 以设计学和类型学为理论依据,通过现代版式设计方法,以界行与版框为宋刻本版式内部分割与外部比例的设计标准,建立基于宋寸的模块网格对宋刻本版式进行尺度比对分析。结果 以浙江地区、福建地区、四川地区为代表的宋代刻书中心地域刻本版面范式设计的基本用尺,主要包括营造尺、浙尺、福建乡尺、太府尺、淮尺。结论 受宋室南迁、人口流动的多重因素影响,宋代官尺与地方用尺通用并存在尺度比例关系。通过对宋代刻书中心刻本版式用尺标准的判定,理解不同时空和不同出版机构宋刻本版面范式设计之间的地缘性尺度关系。以宋代尺度系统的发展脉络来鉴别宋刻本的年代出处,为宋刻本版本鉴定提供一种新的研究思路,拓展宋刻本版面设计的研究范畴。     

聚焦矩阵在水中宽带目标被动跟踪中的应用

针对水中机动宽带目标,对于设计好的均匀线列阵,采用空间重采样方法计算基阵的恒定束宽阵元权系数,进而利用该阵元权系数产生聚焦矩阵,通过聚焦矩阵将不同频带的子带信号映射到同一参考频率上,然后将所有频率成分的信号功率谱密度矩阵作平均,并结合MUSIC(Multiple Signal Classification)算法,估计出目标的方位信息,从而实现水中宽带目标的被动跟踪。采用该方法进行仿真试验分析,结果表明在小孔径基阵上可实现宽带单目标的稳定测向被动跟踪,且对多目标具有一定的角被动分辨效果。     

Is e-reading environmentally more sustainable than conventional reading?

Technology is changing the way we read, with printed material being replaced by electronically published text such as e-books and e-newspapers. Although digitally published texts offer some advantages over printed material in terms of cost and ease of access, it is not immediately clear whether e-reading is environmentally a more sustainable alternative to conventional reading. Therefore, this paper reviews the literature and compares the environmental impacts of the two reading alternatives, taking a life cycle approach. The review of various studies indicates that there are large variations in the impacts for e-readers as well as the printed material, mainly owing to different assumptions. Nevertheless, the results of this work indicate clearly that e-reading can only be environmentally sustainable at very high usage rates, as manufacturing of e-readers has relatively high environmental impacts.     

一种针对印刷稿的图像质量评价应用流程

以印刷稿中的图像为研究对象,印刷稿的图像质量评价为研究目标,建立了图像质量评价指标的应用流程。 该流程首先扫描印刷稿,再对扫描稿进行图像配准处理,然后嵌入特殊的扫描仪特性文件,再用图像评价指标计算出该图像与原稿之间相应的图像质量指数,从而评价印刷稿中的图像质量。 验证实验表明,提出的应用流程具有相当的合理性和可行性。     

ICT for development in Tunisia: “Going the last mile”

This paper seeks to provide an overview of achievements and caveats related to ICT strategies for development in Tunisia. We go beyond a conventional approach of digital divide by considering exclusion from or inequalities in access to high-speed wired broadband infrastructure as a significant explanative variable in this area. Accordingly, we link the roles of ICT as enablers of new opportunities for socio-economic growth to the development of the last mile of the wired broadband infrastructure. Our analysis of the Tunisian ICT environment shows a prevalence of mobile technologies for Internet access and telephony as well as regional and social disparities in availability, access to and use of wired broadband technologies and services. Despite the real interest of Tunisian society and economy in using Internet, the range of broadband enabled-services and applications is rather limited. Additionally, the Tunisian case provides a promising perspective as there is a relatively well developed fibre backbone and potentially good opportunity for developing the last mile of wired infrastructure. We therefore suggest that it is necessary to develop a governmental policy in collaboration with the private sector to further develop the last mile section as well as to overcome weaknesses in the current regulatory frameworks.     

Band-limited image plane masks for the Terrestrial Planet Finder coronagraph: materials and designs for broadband performance

Coronagraphs for detection and characterization of exosolar earthlike planets require accurate masks with broadband performance in the visible and near infrared spectrum. Design and fabrication of image plane masks capable of suppressing broadband starlight to 10(-10) level contrast presents technical challenges. We discuss basic approaches, material choices, designs, and fabrication options for image plane masks with particular focus on material properties to obtain adequate spectral performance. Based on theoretical analysis, we show that metals such as Pt and Ni, and alloys such as Inconel, may be employed as promising mask materials that can meet broadband performance requirements.     

Characteristics of a broadband dye laser using Pyrromethene and Rhodamine dyes

A broadband dye laser pumped by a frequency-doubled Nd:YAG laser with a full width at half-maximum from 592 to 610?nm was created for the use in a dual-pump broadband coherent anti-Stokes Raman spectroscopy (CARS) system called width increased dual-pump enhanced CARS (WIDECARS). The desired broadband dye laser was generated with a mixture of Pyrromethene dyes as an oscillator gain medium and a spectral selective optic in the oscillator cavity. A mixture of Rhodamine dyes was used in the amplifier dye cell. To create this laser, a study was performed to characterize the spectral behavior of broadband dye lasers created with Rhodamine dyes 590, 610, and 640 and Pyrromethene dyes 597 and 650, as well as mixtures of these dyes.     

基于粗糙集的印刷锡膏自动识别和定位

为了准确获取贴装后印刷电路板(PCB)上锡膏的印刷位置,提出了一种综合了锡膏颜色和纹理特征的粗糙集方法.以红、绿、蓝三种颜色分量直方图特征为等价关系求得锡膏印刷区域的上近似集;以均值,方差和一致性等纹理特征为等价关系获得锡膏的下近似集;分别计算上、下近似集的相对权重,获得分割后的锡膏印刷区域的重心.实验结果表明,综合了颜色和纹理信息的粗糙集方法,定位精度为1个像素,定位速度约为10 ms,精度高,速度快.     

Fully printed separated carbon nanotube thin film transistor circuits and its application in organic light emitting diode control

The advantages of printed electronics and semiconducting single-walled carbon nanotubes (SWCNTs) are combined for the first time for display electronics. Conductive silver ink and 98% semiconductive SWCNT solutions are used to print back-gated thin film transistors with high mobility, high on/off ratio, and high current carrying capacity. In addition, with printed polyethylenimine with LiClO4 as the gating material, fully printed top-gated devices have been made to work as excellent current switches for organic light emitting diodes (OLEDs). An OLED driving circuit composed of two top-gated fully printed transistors has been fabricated, and the successful control over external OLED is demonstrated. Our work demonstrates the significant potential of using printed carbon nanotube electronics for display backplane applications.     

A New 3D Printing Strategy by Harnessing Deformation,Instability, and Fracture of Viscoelastic Inks

Direct ink writing (DIW) has demonstrated great potential as a multimaterial multifunctional fabrication method in areas as diverse as electronics, structural materials, tissue engineering, and soft robotics. During DIW, viscoelastic inks are extruded out of a 3D printer's nozzle as printed fibers, which are deposited into patterns when the nozzle moves. Hence, the resolution of printed fibers is commonly limited by the nozzle's diameter, and the printed pattern is limited by the motion paths. These limits have severely hampered innovations and applications of DIW 3D printing. Here, a new strategy to exceed the limits of DIW 3D printing by harnessing deformation, instability, and fracture of viscoelastic inks is reported. It is shown that a single nozzle can print fibers with resolution much finer than the nozzle diameter by stretching the extruded ink, and print various thickened or curved patterns with straight nozzle motions by accumulating the ink. A quantitative phase diagram is constructed to rationally select parameters for the new strategy. Further, applications including structures with tunable stiffening, 3D structures with gradient and programmable swelling properties, all printed with a single nozzle are demonstrated. The current work demonstrates that the mechanics of inks plays a critical role in developing 3D printing technology.     

Effect of support on printed properties in fused deposition modelling processes

ABSTRACT

Additive manufacturing still suffers from redundant support material usage when printing parts with overhanging features. All the supports will be removed after fabrication, resulting in wasted materials. There are many works conducted for reducing support waste by improving support strategies. However, using different support strategies may lead to different printed qualities. In this paper, the effect of support strategy on printed qualities is investigated in fused deposition modelling processes. Three different support strategies are adopted for manufacturing the same 3D part. The finished surface roughness and flexural properties are compared for evaluating different support strategies, as well as the material waste and printing time. The results show that different support strategies may result in different printed surface roughness and flexural properties. To achieve the balance between support consumption and properties of printed parts, it becomes necessary to understand the effect of supports on printed qualities for choosing a best support strategy.     

宽带多途信号仿真

文章介绍宽带多途信号软件仿真的实现方法。通过设计一个FIR滤波器拟合指定的目标信号功率谱,产生水下目标辐射噪声信号;再结合多途海洋信道模型,得到经过多途信道传输的接收信号。该方法实现简单,可以仿真具有一定频谱特性的水下运动目标的接收信号。所产生的仿真信号可用于声纳信号处理等方面的研究工作。