Kalviai湖滨别墅

该工程位于立陶宛Kalviai村Kalviai湖畔,其周边大部分地区湖面和混合林。Kalviai每年一月份的平均气温在0℃左右,七月份在18℃左右,相对温和的气候确保了充足的降雨量和降雪量,这些自然因素直接促成了该地区的传统建筑形式的形成——斜坡瓦屋顶、厚重的原木墙壁。但是随着新时代以及立陶宛独立之后新的社会形势的到来,出现了关于如何诠释并发展传统住宅的讨论。以往的实验作品或是西方现代风格的大胆复制,或是沿袭传统住宅模式而缺少创造性。但Kalviai湖滨别墅于2001年落成,立刻赢得建筑专业人士和国内外新闻媒体的广泛赞誉,获得立陶宛建…     

An 8-bit 100-MHz full-Nyquist analog-to-digital converter

An 8-bit 100-MHz full-Nyquist analog-to-digital (A/D) converter using a folding and interpolation architecture is presented. In a folding system a multiple use of comparator stages is implemented. A reduction in the number of comparators, equal to the number of times the signal is folded, is obtained. However, every quantization level requires a folding stage, thus no reduction in input circuitry is found. Interpolation between the outputs of the folding stages generates additional folding signals without the need for input stages. A reduction in input circuitry equal to the number of interpolations is obtained. The converter is implemented in an oxide-isolated bipolar process, requiring 800 mW from a single 5.2-V supply. A high-level model describing distortion caused by timing errors is presented. Considering clock timing accuracies needed to obtain the speed requirement, this distortion is thought to be the main speed limitation     

Polypropylene composites reinforced with untreated and chemically treated coir: Effect of the presence of compatibilizer

The effect of coir surface modification on the compatibility of polypropylene (PP)/coir fiber (CF) composites, in the presence and absence of compatibilizer (maleic anhydride grafted polypropylene, PP‐g‐MA) was assessed. Chemical pulping of the fibers was performed with 2, 4, 8, and 12% NaOH solutions for a period of 2 h at (100 ± 4)°C. Pressed composite samples were subjected to tensile testing, scanning electron (SEM) and atomic force microscopy (AFM). Lignin and holocellulose concentrations of untreated and treated coir were determined. Pulping resulted in increased tensile strength of the composites containing coir treated with up to 2% NaOH, due to increased fiber roughness as evidenced by AFM. This property decreased when higher NaOH concentrations were used, likely due to increased deterioration of coir. The presence of compatibilizer in the PP composites containing treated coir altered adhesion due to chemical changes of the fiber surface. At high NaOH concentrations increased delignification and therefore increased exposure of hydroxyls favors reaction between the fiber hydroxyls and the carboxyl acids of the hydrolyzed maleic anhydride, present in the composites. POLYM. ENG. SCI., 55:2050–2057, 2015. © 2014 Society of Plastics Engineers     

Efficient engineering through computer-aided design of experiments

Computer-aided design of experiments (CADOE) is discussed. Work performed using ECHIP software to meet quality and productivity goals for injection molded plastic components is detailed. An example of a fan shroud clearly shows that CADOE provides a powerful and efficient method for solving engineering problems. Although in some cases Taguchi methods may be slightly more accurate, CADOE methods such as ECHIP will usually find a solution to problems with a reduction in time and costs required. The actual time required to run the molding trials for the fan shroud was 3-0.5 h, plus 1 h of running time to confirm the predicted values on a faster molding cycle     

Substrate transfer for RF technologies

The constant pressure on performance improvement in RF processes is aimed at higher frequencies, less power consumption, and a higher integration level of high quality passives with digital active devices. Although excellent for the fabrication of active devices, it is the silicon substrate as a carrier that is blocking breakthroughs. Since all devices on a silicon wafer have a capacitive coupling to the resistive substrate, this results in a dissipation of RF energy, poor quality passives, cross-talk, and injection of thermal noise. We have developed a low-cost wafer-scale post-processing technology for transferring circuits, fabricated with standard IC processing, to an alternative substrate, e.g., glass. This technique comprises the gluing of a fully processed wafer, top down, to an alternative carrier followed by either partial or complete removal of the original silicon substrate. This effectively removes the drawbacks of silicon as a circuit carrier and enables the integration of high-quality passive components and eliminates cross-talk between circuit parts. A considerable development effort has brought this technology to a production-ready level of maturity. Batch-to-batch production equipment is now available and the technology and know-how are being licensed. In this paper, we present four examples to demonstrate the versatility of substrate transfer for RF applications.     

A 3.5-mW, 2.5-GHz diversity receiver and a 1.2-mW, 3.6-GHz VCO insilicon on anything

In this paper, first results of radio-frequency (RF) circuits processed in a novel silicon bipolar technology called silicon on anything (SOA) are presented. This technology was developed with the application of low-power, high-frequency circuits in mind. Three test ICs are discussed: a fully integrated 3.6-GHz voltage-controlled oscillator, a fully integrated 2.5-GHz diversity receiver front end, and an intermediate-frequency IC containing channel selectivity and demodulation circuits. Measurement results show that using this technology, significant power savings are possible for RF circuits     

Study of the relation between dose of ionizing radiation and level of chromosome abnormalities in an adult patient following total body irradiation

The dose-effect relationship for dicentric chromosome aberrations and centric rings was studied in a female patient exposed to whole-body gamma irradiation for myeloid leukaemia. Samples were taken before and at different times during the exposure. The dose-effect relationship is on the linear-quadratic type and practically identical with those found earlier when the blood from adults and children was irradiated in vitro and only slightly above that of children irradiated in vivo.     

CATALYTIC PROCESSING OF HEAVY CRUDE OILS AND RESIDUALS II. DIFFUSIONAL LIMITATIONS AND DEACTIVATION PHENOMENA

In the past two decades, there has been a considerable effort directed towards the development of effective processes for upgrading heavy oil and residual feedstocks. These materials are more difficult to process than lighter feedstocks because of their large molecular size and heteroatom and metals content. Significant diffusional limitations arise because the molecular size of the constituents of these feedstocks is large relative to typical catalyst pore sizes. The high heteroatom and metals content leads to the deposition of coke and metal sulfides on the catalyst surface. These deposits decrease the intrinsic activity of the surface as well as the catalyst pore size which causes a reduction in reactant diffusion rates within the catalyst. A sound understanding of these two important phenomena is necessary for the development of effective catalysts and catalytic processes for hydrotreating these materials.

In this article, recent literature dealing with two significant problems In catalytic processing of heavy oils is reviewed. Results from Investigations of the diffusional characteristics of these materials in small pores and some of the complex problems with catalyst deactivation are discussed.     

Membrane rejection of nonspherical particles: Modeling and experiment

The rejection coefficient of nonspherical particles from ultrafiltration and microfiltration membranes has been examined from both theoretical and experimental perspectives. Modeling efforts focused on incorporating the convective hindrance factor for a capsule shaped particle in a cylindrical pore into predictions of the rejection coefficient. First, the convective hindrance factor was approximated using previously reported results for the hydrodynamic resistances experienced by a sphere in a pore. Second, computational fluid dynamics calculations predicted the convective hindrance factor for a capsule in a cylindrical pore. Results from both approaches indicate that including hydrodynamic interactions in predictions of the rejection coefficient has a greater effect for smaller particles and particles with smaller aspect ratio (i.e., close to spherical shape). Rejections of several rod‐shaped Gram negative bacteria with aspect ratio from 2 to 5 by clean track‐etched membranes were in general agreement with theoretical predictions. © 2013 American Institute of Chemical Engineers AIChE J, 59: 3863–3873, 2013