Architectural Growth of Cu Nanoparticles Through Electrodeposition

Cu particles with different architectures such as pyramid, cube, and multipod have been successfully fabricated on the surface of Au films, which is the polycrystalline Au substrate with (111) domains, using the electrodeposition technique in the presence of the surface-capping reagents of dodecylbenzene sulfonic acid and poly(vinylpyrrolidone). Further, the growth evolution of pyramidal Cu nanoparticles was observed for the first time. We believe that our method might open new possibilities for fabricating nanomaterials of non-noble transition metals with various novel architectures, which can then potentially be utilized in applications such as biosensors, catalysis, photovoltaic cells, and electronic nanodevices.     

Nutrient and polyphenolic composition of industrial strawberry press cake

The objective of the present work was to determine the nutrient and polyphenolic composition of dried strawberry press cake (SPC), as well as that of its seedless fraction, termed exhausted strawberry flesh (ESF). The study materials were obtained over three consecutive years from an industrial facility manufacturing concentrated fruit juices. On average, SPC consists of 40 % seeds, 3.5 % sand, and about 55 % ESF. In the dry matter of SPC and ESF, the mean content of fat is 9.8 and 3.5 %, protein 17.3 and 20.4 %, and total polyphenols 3,449 and 5,410 mg/100 g, respectively. Both materials are rich in total dietary fiber, whose content amounts to 60 %. The predominant polyphenols in SPC and ESF are flavanols and ellagitannins, which collectively constitute over 95 % of the determined total polyphenol content. In ESF composition, of note is the high content of the strawberry ellagitannin, agrimoniin, which is approximately 1,000 mg/100 g DW (dry weight). SPC has the disadvantage of being highly contaminated with sand (3.4 %), which accumulates in ESF (5.6 %). However, as compared to SPC, ESF contains approximately 20 % more proteins and almost three times less fat. Based on our results, it appears that SPC may be considered a potential raw material for seed recovery. Moreover, dried strawberry press cake, and especially its seedless fraction (ESF), despite substantial contamination with sand, may be used as rich and widely available raw material for the extraction of proanthocyanidins and/or ellagitannins, and especially dimeric agrimoniin.     

Taguchi method-based sensitivity study of design parameters representing specific strength of wire-woven bulk Kagome under compression

Wire-woven bulk Kagome (WBK) is a new truss-type cellular metal fabricated by assembling helically-formed wires. In this work, the main design parameters governing the compressive strength of WBK were selected from various geometric and material factors. The Taguchi method was used to minimize the number of experiments required to evaluate the sensitivity of each design parameter with the specific compressive strength of WBK. As numerical experiments, finite element analyses were performed to investigate the mechanical responses of WBK with various combinations of levels for selected design parameters. We found that the slenderness ratio is the dominant and most influential design parameter characterizing the specific strength of WBK, followed by the strain-hardening exponent and the yield strength of the brazed filler metal. The height of the braze normalized by the wire diameter is the least influential design parameter. In addition, an optimized design for the highest specific strength of WBK was derived.     

GA-based decision support systems for precast production planning

Appropriate production plans can produce effective resource utilization and minimize waste. However, most precast fabricators currently propose production plans depending on the rule of thumb, resulting in squandered resources and postponed delivery. Computerized scheduling techniques provide more precise outcomes than manual scheduling. The objective of this study is to develop GA-based Decision Support Systems (GA-DSS) to assist production managers in arranging production plans. This research first establishes a flowshop sequencing model based on the current production status by considering the buffer sizes between production stations. A multiple objective genetic algorithm is then applied to search for solutions with minimum makespan and tardiness penalties. The GA-DSS performance is verified using two examples. The results demonstrate that the proposed system can offer appropriate production plans. By taking buffer sizes into consideration more reasonable and feasible production sequences can be achieved.     

Analysis for seismic response of dry storage facility for spent fuel

Most of the dry storage systems for spent fuel are freestanding, which leads to stability concerns in an earthquake. In this study, as a safety check, the ABAQUS/Explicit code is adopted to analyse the seismic response of the dry storage facility planned to be installed at Nuclear Power Plant #1 (NPP1) in Taiwan. A 3D coupled finite element (FE) model was established, which consisted of a freestanding cask, a concrete pad, and underneath soils interacting with frictional contact interfaces. The scenario earthquake used in the model included an artificial earthquake compatible to the design spectrum of NPP1, and a strong ground motion modified from the time history recorded during the Chi-Chi earthquake. The results show that the freestanding cask will slide, but not tip over, during strong earthquakes. The scale of the sliding is very small and a collision between casks will not occur. In addition, the differential settlement of the foundation pad that takes place due to the weight of the casks increases the sliding potential of the casks during earthquakes.     

A genetic-fuzzy-neuro model encodes FNNs using SWRM and BRM

Genetic algorithms (GAs), fuzzy logic (FL), and neural networks (NNs) are frequently used artificial intelligence (AI) techniques. Since these three methods are complementary rather than competitive, many researchers have hybridized GAs, FL, and NNs to develop a better performance model. However, most hybrid models use a multistage combination or identify partial parameters required in the model resulting in sub-optimal solutions. This research fuses GAs, FL, and NNs to develop an evolutionary fuzzy neural inference model (EFNIM) that uses GAs to simultaneously search for all parameters required in fuzzy neural networks (FNNs). Two approaches, summit and width representation method (SWRM) and block-representation method (BRM), are proposed to encode variables in FL and NNs. Simulations are conducted to evaluate the performance of EFNIM. For different problems, membership functions (MFs) with the minimum FNN structure and optimal parameters of FNN are automatically and concurrently acquired using EFNIM. The research overcomes the difficulties faced in applying FL and NNs as well as saves efforts in trial-and-error experiments, questionnaire survey, interviews with experts, etc. Both prediction accuracy and time requirement for cost estimating are much improved by the proposed method.     

Lift and multiple equilibrium positions of a single particle in Newtonian and Oldroyd-B fluids

A heavy particle is lifted from the bottom of a channel in a plane Poiseuille flow when the Reynolds number is larger than a critical value. In this paper we obtain correlations for lift-off of particles in Oldroyd-B fluids. The fluid elasticity reduces the critical shear Reynolds number for lift-off. The effect of the gap size between the particle and the wall, on the lift force, is also studied. A particle lifted from the channel wall attains an equilibrium height at which its buoyant weight is balanced by the hydrodynamic lift force. Choi and Joseph [Choi HG, Joseph DD. Fluidization by lift of 300 circular particles in plane Poiseuille flow by direct numerical simulation. J Fluid Mech 2001;438:101-128] first observed multiple equilibrium positions for a particle in Newtonian fluids. We report several new results for the Newtonian fluid case based on a detailed study of the multiple equilibrium solutions, e.g. we find that at a given Reynolds number there are regions inside the channel where no particle, irrespective of its weight, can attain a stable equilibrium position. This would result in particle-depleted zones in channels with Poiseuille flows of a dilute suspension of particles of varying densities. Multiple equilibrium positions of particles are also found in Oldroyd-B fluids. All the results in this paper are based on 2D direct numerical simulations.     

Corneal Imaging System: Environment from Eyes

This paper provides a comprehensive analysis of exactly what visual information about the world is embedded within a single image of an eye. It turns out that the cornea of an eye and a camera viewing the eye form a catadioptric imaging system. We refer to this as a corneal imaging system. Unlike a typical catadioptric system, a corneal one is flexible in that the reflector (cornea) is not rigidly attached to the camera. Using a geometric model of the cornea based on anatomical studies, its 3D location and orientation can be estimated from a single image of the eye. Once this is done, a wide-angle view of the environment of the person can be obtained from the image. In addition, we can compute the projection of the environment onto the retina with its center aligned with the gaze direction. This foveated retinal image reveals what the person is looking at. We present a detailed analysis of the characteristics of the corneal imaging system including field of view, resolution and locus of viewpoints. When both eyes of a person are captured in an image, we have a stereo corneal imaging system. We analyze the epipolar geometry of this stereo system and show how it can be used to compute 3D structure. The framework we present in this paper for interpreting eye images is passive and non-invasive. It has direct implications for several fields including visual recognition, human-machine interfaces, computer graphics and human affect studies. This research was conducted while the first author was affiliated with Columbia University. A shorter version of this paper appeared in (Nishino and Nayar, 2004).     

An Exploratory Study of How Developers Seek, Relate, and Collect Relevant Information during Software Maintenance Tasks

Much of software developers' time is spent understanding unfamiliar code. To better understand how developers gain this understanding and how software development environments might be involved, a study was performed in which developers were given an unfamiliar program and asked to work on two debugging tasks and three enhancement tasks for 70 minutes. The study found that developers interleaved three activities. They began by searching for relevant code both manually and using search tools; however, they based their searches on limited and misrepresentative cues in the code, environment, and executing program, often leading to failed searches. When developers found relevant code, they followed its incoming and outgoing dependencies, often returning to it and navigating its other dependencies; while doing so, however, Eclipse's navigational tools caused significant overhead. Developers collected code and other information that they believed would be necessary to edit, duplicate, or otherwise refer to later by encoding it in the interactive state of Eclipse's package explorer, file tabs, and scroll bars. However, developers lost track of relevant code as these interfaces were used for other tasks, and developers were forced to find it again. These issues caused developers to spend, on average, 35 percent of their time performing the mechanics of navigation within and between source files. These observations suggest a new model of program understanding grounded in theories of information foraging and suggest ideas for tools that help developers seek, relate, and collect information in a more effective and explicit manner