3D face and motion estimation from sparse points using adaptive bracketed minimization

This paper presents a novel method for estimating camera motion and reconstructing human face from a video sequence. The coarse-to-fine method is applied via combining the concepts of Powell’s minimization with gradient descent. Sparse points defining the human face in every frame are tracked using the active appearance model. The case of occluded points, even for self-occlusion, does not pose a problem in the proposed method. Robustness in the presence of noise and 3D accuracy using this method is also demonstrated. Examples of face reconstruction using other methods including trifocal tensor, Powell’s minimization, and gradient descent are also compared to the proposed method. Experiments on both synthetic and real faces are presented and analyzed. Also, different camera movement paths are illustrated. All real-world experiments used an off-the-shelf digital camera carried by a human walking without using any dolly to demonstrate the robustness and practicality of the proposed method.     

Structural change and Thailand energy demand

This paper examines the impact of changes in the structure of the economy, radical changes in economic policy and oil price shocks on the relation between Thailand energy demand and its macroeconomic determinants. The impact of these structural changes on the relationship between energy consumption, income, energy prices and structural variation is examined through unit root and cointegration tests, the cointegration relationship and the error correction model. Methods which endogenize the location of an a priori unknown break point are employed to assess the impact of structural change. In general, the recognition of structural change has lead to some unique insights. In particular, the results of some of the conventional unit root and cointegration tests are reversed once structural changes are recognized. Estimates from the cointegrating regression imply long-run income, price, and structural variation elasticities of 0.568, −0.600 and 1.046, respectively. In comparison, estimates from the error correction model suggest a higher short-run income elasticity (0.788) but lower short-run price and structural variation elasticities (−0.522 and 0.491, respectively). One of the important implications of the estimates pertains to the low price elasticity for aggregate energy demand which implies that the over-pricing of energy as a policy instrument is not likely to be very influential for restraining future energy demand. Additionally, taxes on energy prices are unlikely to achieve government goals for energy conservation and environmental improvement, although they may well be efficient for raising revenue. Copyright © 2006 John Wiley & Sons, Ltd.     

Predicting performance of radial flow type impeller of centrifugal pump using CFD

The main objective of this work is to use the computational fluid dynamics (CFD) technique in analyzing and predicting the performance of a radial flow-type impeller of centrifugal pump. The impeller analyzed is at the following design condition: flow rate of 528 m³/hr; speed of 1450 rpm; and head of 20 m or specific speed (N_s) of 3033 1/min in US-Units. The first stage involves the mesh generation and refinement on domain of the designed impeller. The second stage deals with the identification of initial and boundary conditions of the mesh-equipped module. In the final stage, various results are calculated and analyzed for factors affecting impeller performance. The results indicate that the total head rise of the impeller at the design point is approximately 19.8 m. The loss coefficient of the impeller is 0.015 when 0.6 < Q/Q_design < 1.2. Maximum hydraulic efficiency of impeller is 0.98 at Q/Q_design = 0.7. Based on the comparison of the theoretical head coefficient and static pressure rise coefficient between simulation results and experimental data, from previous work reported in the literature [Guelich, Kreiselpumpen, Springer, Berlin, 2004], it is possible to use this method to simulate the performance of a radial-flow type impeller of a centrifugal pump. This paper was recommended for publication in revised form by Associate Editor Seungbae Lee Somchai Wongwises is currently a Professor of Mechanical Engineering at King Mongkut’s University of Technology Thonburi, Bangmod, Thailand. He received his Doktor Ingenieur (Dr.Ing.) in Mechanical Engineering from the University of Hannover, Germany, in 1994. His research interests include two-phase flow, heat transfer enhancement, and thermal system design. Professor Wongwises is the head of the Fluid Mechanics, Thermal Engineering and Two-Phase Flow Research Laboratory (FUTURE). Suthep Kaewnai obtained a B. S. degree in Mechanical Engineering, 1980 from the King Monkut’s University of Technology Thonburi and M. S. degree in Mechanical Engineering, 1983 from Chulalongkorn University. He is currently an assistant professor at King Mongkut’s University of Technology Thonburi. Suthep’s research interests are in the area of pumps and small hydroturbine. Manuspong Chamaoot received a B. S. degree, 1972 and M.S. degree in Mechanical Engineering, 1979 from the King Monkut’s University of Technology Thonburi. He is currently an assistant professor at King Monkut’s University of Technology Thonburi. His research interests are in the field of mechanical vibration for rotating equipment and computational fluid dynamics.     

On solving the minimization problem and the fixed-point problem for nonexpansive mappings in CAT(0) spaces

We propose a new modified proximal point algorithm combined with Halpern's iteration process for nonexpansive mappings in the framework of CAT(0) spaces. We establish a strong convergence theorem under some mild conditions. Our results extend some known results which appeared in the literature.     

2D Pose-Invariant Face Recognition Using Single Frontal-View Face Database

Wireless Personal Communications - Personal identification systems that use face recognition work well for test images with frontal view face, but often fail when the input face is a pose view....     

Existence and iteration for a mixed equilibrium problem and a countable family of nonexpansive mappings in Banach spaces

We prove the existence of a solution of the mixed equilibrium problem (MEP) by using the KKM mapping in a Banach space setting. Then, by virtue of this result, we construct a hybrid algorithm for finding a common element in the solutions set of a mixed equilibrium problem and the fixed points set of a countable family of nonexpansive mappings in the frameworks of Banach spaces. By using a projection technique, we also prove that the sequences generated by the hybrid algorithm converge strongly to a common element in the solutions set of MEP and common fixed points set of nonexpansive mappings. Moreover, some applications concerning the equilibrium and the convex minimization problems are obtained.     

Nonlinear iterative methods for solving the split common null point problem in Banach spaces

In this work, we study the split common null point problem in the framework of Banach spaces. We propose an iterative scheme for solving the problem and then prove strong convergence theorem of the sequences generated by our iterative scheme under suitable conditions. We finally provide some numerical examples to support the main theorem.     

Concentrations of total and inorganic arsenic in fresh fish, mollusks, and crustaceans from the Gulf of Thailand

Concentrations of total and inorganic arsenic were determined in 120 samples of eight marine animals collected from the Gulf of Thailand between March and May 2008. Two species with the highest annual catch from each of four marine animal groups were analyzed: fish (Indo-Pacific mackerel and goldstripe sardine), bivalves (green mussel and blood cockle), cephalopods (pharaoh cuttlefish and Indian squid), and crustaceans (banana prawn and swimming crab). Concentrations of inorganic arsenic based on wet weight ranged from 0.012 μg/g in Indian squids to 0.603 μg/g in blood cockles. Average percentages of inorganic arsenic with respect to total arsenic ranged from 1.2% in banana prawns to 7.3% in blood cockles. Blood cockles also exhibited the highest levels of total arsenic (5.26 ± 2.01 μg/g) and inorganic arsenic (0.352 ± 0.148 μg/g). The levels of inorganic arsenic in the study samples were much lower than the Thai regulatory limit of 2 μg/g (wet wt) and hence are safe for human consumption.