Object Bank: An Object-Level Image Representation for High-Level Visual Recognition

It is a remarkable fact that images are related to objects constituting them. In this paper, we propose to represent images by using objects appearing in them. We introduce the novel concept of object bank (OB), a high-level image representation encoding object appearance and spatial location information in images. OB represents an image based on its response to a large number of pre-trained object detectors, or ‘object filters’, blind to the testing dataset and visual recognition task. Our OB representation demonstrates promising potential in high level image recognition tasks. It significantly outperforms traditional low level image representations in image classification on various benchmark image datasets by using simple, off-the-shelf classification algorithms such as linear SVM and logistic regression. In this paper, we analyze OB in detail, explaining our design choice of OB for achieving its best potential on different types of datasets. We demonstrate that object bank is a high level representation, from which we can easily discover semantic information of unknown images. We provide guidelines for effectively applying OB to high level image recognition tasks where it could be easily compressed for efficient computation in practice and is very robust to various classifiers.     

Toward seed-insensitive solutions to local community detection

Local community detection aims at finding a community structure starting from a seed which is a given vertex in a network without global information, such as online social networks that are too large and dynamic to ever be known fully. Nonetheless, the existing approaches to local community detection are usually sensitive to seeds, i.e., some seeds may lead to missing of some true communities. In this paper, we present a seed-insensitive method called GMAC and its variation iGMAC for local community detection. They estimate the similarity among vertices by investigating vertices’ neighborhoods, and reveal a local community by maximizing its internal similarity and minimizing its external similarity simultaneously. Extensive experimental results on both synthetic and real-world data sets verify the effectiveness of our algorithms.     

Coordinated formation pattern control of multiple marine surface vehicles with model uncertainty and time-varying ocean currents

This paper presents a data-driven modeling and optimization method for cavity filters, according to a limited amount of measurement data. In the method, a model that reveals the effect of mechanical structure on electrical performance of cavity filters is firstly developed by an improved algorithm, which can increase the modeling accuracy of small data set by incorporating multi-kernel and prior knowledge into the framework of linear programming support vector regression. Then, an approach to optimize the structure of cavity filters is formulated by using the developed data-based model, and the obtained results can assist the fabrication of the same filter in the future. Some experiments from a synthetic example and a practical application of cavity filter have been carried out, and the experimental results confirm the effectiveness of the method. The model is particularly suited to a computer-aided manufacturing of volume-producing filters, and the proposed algorithm shows great potential in some applications where the experimental data are very few and the prior knowledge is available.     

高效节能热泵错流多效蒸发复杂系统

为了大幅降低错流多效蒸发过程的能耗,首次将蒸汽喷射式热泵技术、冷凝水闪蒸和溶液闪蒸等3种节能措施同时运用到错流多效蒸发系统中,并建立了用矩阵方程描述的该系统的数学模型。模型具有很强的通用性,可实现热泵在任意效抽汽的功能,可简化为只有其中若干种节能措施组合或无上述节能措施的错流、并流、逆流多效蒸发系统的模型。在满足约束条件的前提下,模型存在最佳的热泵喷射系数和抽汽位置,同时采用上述3种节能措施且在最佳条件下模型是高效节能的。浓缩氢氧化钠溶液的热泵错流五效蒸发系统的模拟结果表明,当热泵的喷射系数为0.15、抽汽位置在第2效,采用冷凝水闪蒸和溶液闪蒸时系统节省的生蒸汽消耗量高达32.51%。     

电泵井振动监测及传输系统设计

潜油电泵机组是具有超细长转轴的复杂旋转机械,有复杂的生产及安装工艺,且采用了多级离心泵,在生产过程中会产生强大的振动源,测量并分析机组振动状况,是评估潜油电泵机组的运行状况、提高可靠性的重要手段。本文采用MMA3201振动加速度计监测振动状况,并采用4 mA²0 mA电流环将信号传输到井上MCU进行分析处理,根据监测和处理结果,适时提泵检修,采取合理的减振措施,延长潜油电泵的使用寿命。     

无线无源声表面波传感器研究进展

声表面波（SAW）传感器是一种无线无源传感器,在无源传感、适应恶劣环境等许多方面具有普通传感器不能实现的优点.阐述了声表面波器件的原理和结构特点,并对射频信号收发、信息处理等关键技术进行详细论述,综述了近些年国内外的相关研究现状,并进行了总结与展望.     

一种林业手持式多功能测树仪设计

针对森林调查对便携式测量设备自动化和集成化的需求,设计了一种集测高器、角规和标准蓄积量计算功能于一体,具有测量、数据存储、计算等多种功能的手持式多功能电子测树仪GForest。该仪器通过采样控制算法实现对测高器防抖动设计,采用计数器存储并控制角规计数结果,提供USB接口同PC和移动智能终端设备进行数据共享,旨在解决目前森林地面调查数据采集硬件设备信息化与数据采集软件发展不同步的问题,大幅减少了外业调查中手工数据记录和录入的工作,提高了野外数据采集的效率。经实测验证:GForest测得的立木高度与实际值的平均误差为4%,与进口同类设备精度持平,同时还具有角规绕测计数与控制等实用功能,且具有明显的成本优势,适合在行业内推广应用。     

原子磁强计检测光闭环稳定系统设计

SERF态原子磁强计已实现人类历史上最高的0.16fT/Hz1/2的灵敏度。其检测方法主要是法拉第调制法。但法拉第调制法中光电流摄动或环境温度变化等干扰导致的检测光强的起伏会造成检测结果的不准确。为抑制检测光强起伏,设计了闭环原子磁强计检测光稳定系统。在法拉第调制法的基础上,增加了光路子系统和控制子系统对检测光强进行闭环稳定控制。通过对随机干扰进行闭环控制仿真与实验,验证本系统可以有效抑制各种干扰引起的光强起伏,使系统抗干扰能力提高1.2%,从而提高原子磁强计的检测精度。     

Studies on membrane formation mechanism by the light transmission technique. I

New parameters, light transmission rate and minimum light transmissions, are proposed. These two parameters reflect the characteristics of the membrane‐forming system and the formation process of the membranes by phase inversion. The relationship between the light transmission and the porous structure of the membrane can be explained by the geometrical optics principles. Variation of the two parameters combining Reuvers's phase separation theory provided a convenient analytical method to predict effectively membrane morphologies. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 87: 174–181, 2003     

Fabrication and amplification of Rhodamine B‐doped step‐index polymer optical fiber

A step‐index polymer optical fiber (SI POF) containing Rhodamine B in poly(methyl methacrylate) (PMMA) has been fabricated by a preform technique. Fluorescence of different fiber lengths were observed and discussed. A high gain (23 dB) for a SI POF with 60‐cm length, 400‐μm diameter was obtained. The Rhodamine B content of the doped SI POF is 5 ppm‐wt. The signal wavelength providing the highest gain for a 60 cm SI POF is around 630 nm, and the optimum fiber length is about 60 cm at 10 kW launched pump power. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 681–685, 2004