周庄水乡特色初探

文章从水乡周庄的特色定位入手，具体围绕“景点集中、重点突出、尺度适宜、虚实得当”等几个方面分析和探寻了周庄的水乡特色，并对存在的不足提出了建议。     

“These devices have not been made for older people's needs” – Older adults' perceptions of digital technologies in Finland and Ireland

This article examines how older adults use and perceive digital technologies in Finland and Ireland. These two countries are at different stages regarding two important global trends – demographic ageing and digitalization. Finland, being the fastest ageing society in Europe, is also one of the leaders in implementing digital technologies in social and health care services. In contrast, Ireland is a demographically younger and less digitalized society. Drawing on focus group discussions on the usage of digital technologies, conducted with older adults in both countries, we analyse how digital technologies are adopted and viewed by older generations. The analyses showed that older adults associate digitalization with both advantages and drawbacks. To encapsulate these two contrasting aspects, we developed the term Janus-faced conceptions of technology. This concept encapsulates how the successful adoption of digital technology facilitates everyday activities whereas the inability to utilise technologies results in feelings of alienation and being out-of-touch. The digital divide was found to occur not only between generations but also between different socioeconomic groups of older adults.     

Gaussian-Hermite moment-based depth estimation from single still image for stereo vision

Depth information of objects plays a significant role in image-based rendering. Traditional depth estimation techniques use different visual cues including the disparity, motion, geometry, and defocus of objects. This paper presents a novel approach of focus cue-based depth estimation for still images using the Gaussian-Hermite moments (GHMs) of local neighboring pixels. The GHMs are chosen due to their superior reconstruction ability and invariance properties to intensity and geometric distortions of objects as compared to other moments. Since depths of local neighboring pixels are significantly correlated, the Laplacian matting is employed to obtain final depth map from the moment-based focus map. Experiments are conducted on images of indoor and outdoor scenes having objects with varying natures of resolution, edge, occlusion, and blur contents. Experimental results reveal that the depth estimated from GHMs can provide anaglyph images with stereo quality better than that provided by existing methods using traditional visual cues.     

Contour-based focus of attention mechanism to speed up object detection and labeling in 3D scenes

In this paper, a contour-based focus of attention approach is presented. Fast to compute, contour based features are extracted from 3D scenes and matched to model parts of objects. Local reference frames associated with the features induce a translation and rotation, resulting in a vote being cast for the presence of the object in a certain position within the scene. In these positions, HoG features are extracted and SVM classification is applied. Detection results and computation times are compared to those corresponding to a sliding window approach.     

The role of tutors in peer led teaching

Problem based learning can impact not only on students’ academic performance but also their social interactions within their peer group, and many institutions have embedded such teaching within their core curriculum. This paper looks at the interactions within a first year undergraduate engineering cohort that uses peers to tutor small groups through problem based learning at a Scottish Higher Education Institution. Most significantly, this work focusses on the impact that these interactions have on the students engaged as tutors within the programme, bridging the gap left by previous studies and providing an insight into how tutors are affected by their experiences. It was found that the recruitment of tutors requires careful consideration of their social as well as academic qualities, and that they should receive training and guidance within their adopted roles that takes account of social factors, questioning the traditional practice of employing individuals purely on the basis that they have studied the class previously themselves. The dynamic of tutor position with regard to the presence of senior staff is also explored, and suggests mechanisms for further student development.     

脱散的轨迹 对当代中国建筑师思考与实践发展脉络的另一种描述

文章尝试从部分20世纪50至70年代生当代中国建筑师实践策略和思考关注点的转变中寻觅线索轨迹。分析他们受到现代性话语体系的影响,同时检视他们在中国城市发展现状这一特定语境下的身份定义,进而尝试对当代中国建筑师思考与实践发展脉络进行描述。这一描述不从作品的结果出发作总结性的判断,而通过抽取不同建筑师的策略关注点和关键话语,进一步对贯穿不同时间段、没有因果关系的多重线索进行重新梳理和联结,对还原一个未曾明确的当代中国建筑话语体系给出研究建议。这一新的话语体系或许可以提供一种不同于西方现代性的"脱散的轨迹",从而见证多条线索在当代中国的某种不期而至的交汇或离散。     

Multi-scale weighted gradient-based fusion for multi-focus images

Anisotropic blur and mis-registration frequently happen in multi-focus images due to object or camera motion. These factors severely degrade the fusion quality of multi-focus images. In this paper, we present a novel multi-scale weighted gradient-based fusion method to solve this problem. This method is based on a multi-scale structure-based focus measure that reflects the sharpness of edge and corner structures at multiple scales. This focus measure is derived based on an image structure saliency and introduced to determine the gradient weights in the proposed gradient-based fusion method for multi-focus images with a novel multi-scale approach. In particular, we focus on a two-scale scheme, i.e., a large scale and a small scale, to effectively solve the fusion problems raised by anisotropic blur and mis-registration. The large-scale structure-based focus measure is used first to attenuate the impacts of anisotropic blur and mis-registration on the focused region detection, and then the gradient weights near the boundaries of the focused regions are carefully determined by applying the small-scale focus measure. Experimental results clearly demonstrate that the proposed method outperforms the conventional fusion methods in the presence of anisotropic blur and mis-registration.     

Optimal depth estimation by combining focus measures using genetic programming

Three-dimensional (3D) shape reconstruction is a fundamental problem in machine vision applications. Shape From Focus (SFF) is one of the passive optical methods for 3D shape recovery that uses degree of focus as a cue to estimate 3D shape. In this approach, usually a single focus measure operator is applied to measure the focus quality of each pixel in the image sequence. However, the applicability of a single focus measure is limited to estimate accurately the depth map for diverse type of real objects. To address this problem, we develop Optimal Composite Depth (OCD) function through genetic programming (GP) for accurate depth estimation. The OCD function is constructed by optimally combining the primary information extracted using one/or more focus measures. The genetically developed composite function is then used to compute the optimal depth map of objects. The performance of the developed nonlinear function is investigated using both the synthetic and the real world image sequences. Experimental results demonstrate that the proposed estimator is more useful in computing accurate depth maps as compared to the existing SFF methods. Moreover, it is found that the heterogeneous function is more effective than homogeneous function.     

Simple determination via complex arithmetic of geometric characteristics of Bézier conics

We show how to compute in a straightforward manner the geometric characteristics of a conic segment in rational Bézier form, by employing complex arithmetic. For a central conic, a simple quadratic equation defines the foci location, and its solution furnishes not only an explicit formula for the foci, but also for the center, axis direction and linear eccentricity.