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Near infrared vision was used to quantify feeding behavior of fish.Fish feeding decision was realized using the neuro-fuzzy model.The method performance was evaluated by accuracy, fish growth and water quality.The proposed method can save feed costs and reduce water pollution. In aquaculture, the feeding efficiency of fish is of great significance for improving production and reducing costs. In recent years, automatic adjustments of the feeding amount based on the needs of the fish have become a developing trend. The purpose of this study was to achieve automatic feeding decision making based on the appetite of fish. In this study, a feeding control method based on near infrared computer vision and neuro-fuzzy model was proposed. The specific objectives of this study were as follows: (1) to develop an algorithm to extract an index that can describe and quantify the feeding behavior of fish in near infrared images, (2) to design an algorithm to realize feeding decision (continue or stop) during the feeding process, and (3) to evaluate the performance of the method. The specific implementation process of this study was as follows: (1) the quantitative index of feeding behavior (flocking level and snatching strength) was extracted by Delaunay Triangulation and image texture; (2) the adaptive network-based fuzzy inference system (ANFIS) was established based on fuzzy control rules and used to achieve automatically on-demand feeding; and (3) the performance of the method was evaluated by the specific growth rate, weight gain rate, feed conversion rate and water quality parameters. The results indicated that the feeding decision accuracy of the ANFIS model was 98%. In addition, compared with the feeding table, although this method did not present significant differences in promoting fish growth, the feed conversion rate (FCR) can be reduced by 10.77% and water pollution can also be reduced. This system provides an important contribution to realizing the real-time control of fish feeding processes and feeding decision on demand, and it lays a theoretical foundation for developing fine feeding equipment and guiding practice.

In aquaculture, almost all images collected of an aquaculture scene contain reflections, which often affect the results and accuracy of machine vision. Classifying these images and obtaining images of interest are key to subsequent image processing. The purpose of this study was to identify useful images and remove images that had a substantial effect on the results of image processing for computer vision in aquaculture. In this study, a method for classification of reflective frames based on image texture and a support vector machine (SVM) was proposed for an actual aquaculture site. Objectives of this study were to: (1) develop an algorithm to improve the speed of the method and to ensure that the method has a high classification accuracy, (2) design an algorithm to improve the intelligence and adaptability of the classification, and (3) demonstrate the performance of the method. The results show that the average classification accuracy, false positive rate, and false negative rate for two types of reflective frames (type I and II) were 96.34%, 4.65%, and 2.23%, respectively. In addition, the running time was very low (1.25 s). This strategy also displayed considerable adaptability and could be used to obtain useful images or remove images that have substantial effects on the accuracy of image processing results, thereby improving the applicability of computer vision in aquaculture. Keywords: Aquaculture, Genetic algorithm, Gray level-gradient co-occurrence matrix, Principal component analysis, Reflection frame, Support vector machine.

Delaunay Triangulation was applied to the extraction of behavioral characteristics.Support Vector Machine was used to classify the reflective frame.Serious reflection frames were removed and new data were fitted.The linear correlation coefficient between FIFFB and human expert can reach 0.945. In aquaculture, fish feeding behavior under culture conditions holds important information for the aquaculturist. In this study, near-infrared imaging was used to observe feeding processes of fish as a novel method for quantifying variations in fish feeding behavior. First, images of the fish feeding activity were collected using a near-infrared industrial camera installed at the top of the tank. A binary image of the fish was obtained following a series of steps such as image enhancement, background subtraction, and target extraction. Moreover, to eliminate the effects of splash and reflection on the result, a reflective frame classification and removal method based on the Support Vector Machine and Gray-Level Gradient Co-occurrence Matrix was proposed. Second, the centroid of the fish was calculated by the order moment, and then, the centroids were used as a vertex in Delaunay Triangulation. Finally, the flocking index of fish feeding behavior (FIFFB) was calculated to quantify the feeding behavior of a fish shoal according to the results of the Delaunay Triangulation, and the FIFFB values of the removed reflective frames were fitted by the Least Squares Polynomial Fitting method. The results show that variations in fish feeding behaviors can be accurately quantified and analyzed using the FIFFB values, for which the linear correlation coefficient versus expert manual scoring reached 0.945. This method provides an effective method to quantify fish behavior, which can be used to guide practice.

In aquaculture, the feeding technology determined the feed conversion rate and cost. However, the intelligence of existing feeding devices is not very high. they can’t change the amount of feed according to the fish appetite automatically. In order to solve the above issues, in this paper, a feeding controller based on machine vision and feeding behavior was designed on the basis of the original feeder. The hardware platform was built on the I.MX6 microcontroller, and the software was designed via the embedded Linux OS. Moreover, the feeding behavior analysis and automatic feeding control method based on image processing were also studied. Firstly, the images of fish feeding process were collected and analyzed. Then the Delaunay Triangulation was used to extract the feeding behavior parameter FIFFB (flocking index of fish feeding behavior). Finally, the feeding decision was made according to the defined threshold. Compared with the traditional feeder, the controller designed in this paper is more intelligent and can reduce feed waste. Meanwhile, water pollution also can be reduced. The automatic feeding control was realized during feeding process.

Based on the assumption of spherical grains in polycrystalline materials and the theory of metallography, a mathematical model was developed to calculate the quantitative relationship between apparent and true values of the lamellar spacing cutting through the grain randomly. The results indicate that the grain sizes of most polycrystalline materials are much larger than their lamellar spacings, the ratio of an average apparent value to a true one can be characterized by the corrected coefficient k. The ratio of the apparent lamellar spacing to the grain size reduces from 0.05 to 0.0001, and k increases from 1.5391 to 1.5707, which gradually tends to be π/2. When the ratio of the apparent lamellar spacing to the grain size is smaller than 0.001, value k can be considered as a constant of π/2. The amount of work will be decreased adopting the present model to get the true value of lamellar spacing compared with the conventional methods.

Due to the low and uneven illumination that is typical of a recirculating aquaculture system (RAS), visible and near infrared (NIR) images collected from RASs always have low brightness and contrast. To resolve this issue, this paper proposes an image enhancement method based on the Multi-Scale Retinex (MSR) algorithm and a greyscale nonlinear transformation. First, the images are processed using the MSR algorithm to eliminate the influence of low and uneven illumination. Then, the normalized incomplete Beta function is used to perform a greyscale nonlinear transformation. The function’s optimal parameters (α and β) are automatically selected by the particle swarm optimization (PSO) algorithm based on an image contrast measurement function. This adaptive image enhancement method is compared with other classic enhancement methods. The results show that the proposed method greatly improves the image contrast and highlights dark areas, which is helpful during further analysis of these images.

A binary continuum model for dendritic solidification transport phenomena and corresponding numerical algorithm for the strong nonlinear coupling of T — f S — C L were extended to multicomponent alloys solidified under condition of Biot (0.1. Based on the extended model/algorithm, a method considering heat transfer was proposed to predict the solidification paths and microsegregation of alloys solidified under the same condition. The new algorithm and method were closely coupled with the commercial Thermo-Calc package via its TQ6-interface codes for instantaneous determination of the related thermodynamic data at each calculation time step. The sample simulation performed on an Al-2Si-3Mg alloy system indicates the availability and reliability of the model/algorithm and the proposed method for predicting solidification paths and microsegregation. Computional and experimental investigations on an Al-5.17Cu-2.63Si ternary alloy were conducted, and a reasonable agreement between the computation and experiment was obtained.

本研究では、2国で構成される世界経済を対象として、多国籍企業による組み立て過程のアウトソーシング行動を通じた国際分業・国際貿易パターンを分析するための一般均衡モデルを提案する。2国経済は、それぞれ労働生産性が異なっている。多国籍企業も労働生産性が異質であり、グローバルな独占競争市場において差別化された財を生産・販売する。多国籍企業は、両国における労働生産性の差異に基づいてアウトソーシング先を決定する。その結果、両国間における貿易パターンが内生的に決定される。その上で、国際的社会資本の整備による輸送費用の変化が、多国籍企業の生産拠点配置、貿易パターン、および両国の家計厚生に及ぼす影響を分析する。, In this paper, a two countries model is formulated to investigate the global production-trade patters including outsourcing behavior emerged by the location behaviors of multi-national enterprises. Two countries are characterized by heterogeneous labor productivities. The multi-national enterprises, heterogeneous in productivities, are supposed to provide the differentiated commodities in the monopolistically competitive global market. They determine production locations in the global economy. The comparative static analysis is carried out to investigate the impacts of global infrastructure arrangement, associated with the decrease of transportation costs, upon the optimal production-trade patterns in the economy.

A new seed making method with cold crucible by power off technique was proposed. The cold crucible quenched seed with columnar structure has a similar cross-section shape as that of the cold crucible, and can be directly used for the directional solidification processes. The proposed method can significantly simplify the seeded directional solidification process and avoid the contamination from the seed machining.

Planar, cellular and dendrite morphologies were observed at different concentrations in the directional solidification of Cu-Pb monotectic alloys. In Cu-Pb hypomonotectic alloys, the directional solidification microstructure changes from columnar dendrite to the irregular rod composite structure with increasing lead content and growth rate. In Cu-Pb hypermonotectic alloys, the structure changes from the band structure and elongated droplets to irregular rod composite structure with increasing growth rate. The range of composition of forming the rod composite structure around the monotectic points increases with the increasing growth rate. The transient morphology of Cu-Pb alloys in the directional solidification was obtained. The solid/liquid interface of Cu-Pb alloys presents planar and the second liquid droplets are pushed by growing front under the high temperature gradient With increasing growth rate or decreasing temperature gradient the planar interface becomes unstable and the cellular structures with L 2 phase at the cell boundaries are developed.

The martensite with a P2221 space group has been found in Ti3Al-Nb alloys containing Nb below 5-at% via rapid solidification in the cooling rate of 105 ~ 106K/s. The ordering for the martensite α″0 in the alloys inherited that of the β0 phase. Enormous twins with (111) crystallographic planes were observed in the martensite α″0. The orientation relationships between the α″0 and β0 were derived from the SAED patterns as [110]α″o//[111]βo, (001) α″o //(1 1 0) βo .

(2003). English Language Teaching in East Asia Today: Changing Policies and Practices. Asian Englishes: Vol. 6, No. 1, pp. 86-88.