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Background The aim of this study was to determine preferences regarding transfer of patients with congenital heart disease (CHD) attending a children's hospital in Japan and related factors. Methods and Results: We conducted a self-administered questionnaire survey with CHD patients >15 years of age treated at the pediatric cardiology outpatient clinic of a children's hospital. Logistic regression analysis was used to identify factors related to patient preferences regarding the transfer. One hundred and eleven of the 122 patients given a questionnaire provided valid responses (valid response rate, 91.0%). Sixty-six subjects (64.9%) reported "not being told anything specific" by their physicians about the transfer from the children's hospital, and 72 (59.5%) stated that they "wished to continue attending the children's hospital". Visiting outpatient clinic with parents (OR, 11.00; 95% CI: 2.01-60.97), having low uncertainty about continuing to attend the children's hospital (OR, 0.95; 95% CI: 0.92-0.98), and having high uncertainty about leaving the current physician (OR, 1.04; 95% CI: 1.01-1.07) were significantly related to the patient's wish to continue to attend the children's hospital. Conclusions There is a need to improve patient education regarding the opportunities for transfer, and to develop a systematic transition program for children's hospitals and aligned specialized adult CHD centers. more...

Infantile hemangiomas undergo rapid growth during early infancy followed by gradual involution. Infantile hemangiomas sometimes impair vital functions or cause disfigurement. Thirty-two Japanese patients between the ages of 1 and 4 months with proliferating infantile hemangiomas received oral propranolol on an outpatient basis. The success rate (complete or nearly complete resolution) at week 25 was 56% (18/32). Two patients dropped out because of a personal reason and moving out. Recurrence after termination of treatment was seen in six patients. Adverse events occurred in 16 patients. There were no adverse events on day 1 (initiation of treatment at a dose of 1 mg/kg per day) and day 8 (dose increase to 2 mg/kg per day). One patient was hospitalized due to pneumonia, and suspended propranolol for 26 days. Oral propranolol at 2 mg/kg per day is effective and safe in Japanese patients with infantile hemangiomas. more...

Reports indicate lower Down syndrome (DS) survival among females than among males in Australia, contrasting with female longevity in the general population. Using data on 1310 people with DS (626 females and 684 males) in Japan from five hospitals’ medical records and questionnaires completed by parents of people with DS, we investigated sex differences in congenital heart disease (CHD), which may be related to mortality. The CHD rate was significantly higher for females (354, 57%) than for males (338, 49%; p=0.010). Significantly more females (199, 32%) than males (175, 26%) underwent surgery for CHD (p=0.018). more...

Facial expressions are the straight link for showing human emotions. Psychologists have established the universality of six prototypic basic facial expressions of emotions which they believe are consistent among cultures and races. However, some recent cross-cultural studies have questioned and to some degree refuted this cultural universality. Therefore, in order to contribute to the theory of cultural specificity of basic expressions, from a composite viewpoint of psychology and HCI (Human Computer Interaction), this paper presents a methodical analysis of Western-Caucasian and East-Asian prototypic expressions focused on four facial regions: forehead, eyes-eyebrows, mouth and nose. Our analysis is based on facial expression recognition and visual analysis of facial expression images of two datasets composed by four standard databases CK+, JAFFE, TFEID and JACFEE. A hybrid feature extraction method based on Fourier coefficients is proposed for the recognition analysis. In addition, we present a cross-cultural human study applied to 40 subjects as a baseline, as well as one comparison of facial expression recognition performance between the previous cross-cultural tests from the literature. With this work, it is possible to clarify the prior considerations for working with multicultural facial expression recognition and contribute to identifying the specific facial expression differences between Western-Caucasian and East-Asian basic expressions of emotions. more...

The recent boom of mass media communication (such as social media and mobiles) has boosted more applications of automatic facial expression recognition (FER). Thus, human facial expressions have to be encoded and recognized through digital devices. However, this process has to be done under recurrent problems of image illumination changes and partial occlusions. Therefore, in this paper, we propose a fully automated FER system based on Local Fourier Coefficients and Facial Fourier Descriptors. The combined power of appearance and geometric features is used for describing the specific facial regions of eyes-eyebrows, nose and mouth. All based on the attributes of the Fourier Transform and Support Vector Machines. Hence, our proposal overcomes FER problems such as illumination changes, partial occlusion, image rotation, redundancy and dimensionality reduction. Several tests were performed in order to demonstrate the efficiency of our proposal, which were evaluated using three standard databases: CK+, MUG and TFEID. In addition, evaluation results showed that the average recognition rate of each database reaches higher performance than most of the state-of-the-art techniques surveyed in this paper. more...

We present a framework by which the motion of an autonomous mobile guide robot is adaptively controlled. A sociable robot should adapt its speed and path to suit the users' activities, without restricting the user movement. By generating adaptive artificial potential fields for the users and the subgoal separately, and integrating them with the basic potential fields generated from obstacles, our robot can adapt to the users' activities and provide sociable tour-guide services. The robot predicts a user's moving speed and adapts to it to maintain the social distance. Moreover, with the proposed framework, users can deviate from the guided path temporarily and return to the original task afterward. Instead of waiting for the users and taking the risk of losing them, the robot deviates from its original path to follow the users and also prepares for returning to the guiding task. The robot restarts the guiding task at that place, which ensures the least cost to reach the goal. Simulation and experimental results show that our framework can automatically generate suitable motion patterns to control the robot adaptively, making it sociable while providing tour guide services. © 2016 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. more...

This paper proposes a speed control method to move an autonomous mobile robot safely under the environment where blind areas exist. Sensors like a laser range finder or an optical camera cannot detect the areas in the backside of walls, pillars, or objects. When a person suddenly appears from these blind areas, the mobile robot is very likely to collide with him/her, if its speed reduction performance is limited. In this paper the safety speed of robot is carefully controlled using the distance information between the robot and the blind areas as well as obstacles. Meanwhile, the optimum path is generated to minimize the cost of moving time, considering the lengthened time cost caused by speed control process. The effectiveness of the proposed method is confirmed by both the computer simulation and the experiment using a real robot. more...

To improve the quality of childcare in nursery schools by using information technologies, a childcare assisting system is proposed to help the teachers with their daily works. The first step of the system is automatically monitoring and analyzing the behaviors of the children. In this paper, a multiple children identification and tracking method is proposed by using color and depth information from the sensors setting in the environment. The children are identified by integrating multiple personal information of color, face, moving pattern, and the identification results are used as the observation likelihoods in the particle filter based tracking process. The proposed method can continuously track multiple children under complex environment with occlusions among children and fast motions crossing with each other. The effectiveness of the proposed method is proven by the experiments conducted in a nursery school. more...

Developing a childcare assisting system is highly necessary due to the lack of nursery teachers, and it will make an important progress on effective utilization of nursery teacher resources. In this paper, we proposed simultaneous children recognition and tracking system by using Kinect sensors for the childcare assisting system to provide information for the nursery teachers. Each of the children is recognized by integrating his/her personal information of color, face and motion. The tracking problem is modeled as finding the MAP solution of a posterior probability, and is solved by using Markov Chain Monte Carlo (MCMC) particle filter. Our system can recognize and robustly track each child during class activities. Trajectories, motion ranges and relative distances information can be provided for the nursery teachers to assist their childcare work. The effectiveness of our system is proved through continuous monitoring of the children in a nursery school. more...

SUMMARY Mobile robots need Simultaneous Localization and Mapping (SLAM) for autonomous movement in human living environments. The occupancy grid map used in SLAM is a conventional method which makes a map by an occupancy probability in each grid. This method renews a map based on whether an object is observed or not. In order to remove moving objects from a map, an additional method is required. However, conventional methods deal only with actually moving objects, and potential moving objects (e.g., standing humans) are mapped as static objects. Furthermore, only binary states, used or not used, are given to each object in map updating. This paper proposes the immobility area grid map to represent a map by an immobility probability in each grid. The proposed method renews a map based on the identification of observed objects by a robot's sensors, in addition to whether an object is observed or not. We introduce the map update parameter, which is set adaptively from the certainty of identification result of the object. Observed objects can take continuous states, truly static—unknown—truly moving, according to the parameter value. Potential moving objects are not mapped if the parameter takes values corresponding to moving objects. The experimental results show robust mapping in dynamic environments including potential moving objects. more...

IMPORTANCE: Few studies with sufficient statistical power have shown the association of the z score of the coronary arterial internal diameter with coronary events (CE) in patients with Kawasaki disease (KD) with coronary artery aneurysms (CAA). OBJECTIVE: To clarify the association of the z score with time-dependent CE occurrence in patients with KD with CAA. DESIGN, SETTING, AND PARTICIPANTS: This multicenter, collaborative retrospective cohort study of 44 participating institutions included 1006 patients with KD younger than 19 years who received a coronary angiography between 1992 and 2011. MAIN OUTCOMES AND MEASURES: The time-dependent occurrence of CE, including thrombosis, stenosis, obstruction, acute ischemic events, and coronary interventions, was analyzed for small (z score more...

Infantile hemangiomas are the most common tumor of childhood and undergo rapid growth during early infancy followed by gradual involution. After involution, residual lesions sometimes remain. Oral propranolol usually induces earlier involution and redness reduction of infantile hemangiomas. However, the optimal treatment duration is unknown and infantile hemangiomas sometimes recur after cessation of treatment. We report three Japanese patients with recurrent infantile hemangiomas on their cheek. These patients were a 1-month-old female baby with a superficial infantile hemangioma, a 3-month-old female baby with a mixed infantile hemangioma and a 4-month-old male baby with a mixed infantile hemangioma. Two of them also received pulsed dye laser treatment. They did not reach complete or nearly complete resolution of infantile hemangiomas at week 25. These patients experienced regrowth of their infantile hemangioma after 20 months of age and took propranolol after the age of 24 months. There were no severe adverse effects. Propranolol may not only be therapeutic but also prophylactic. Patients with infantile hemangiomas who have taken oral propranolol should be followed up at least 6 months after cessation of treatment, especially infantile hemangiomas on the cheek, and those with partial response to propranolol may require close attention in prolonged growth. more...

In order to move around automatically, mobile robots usually need to recognize their working environment first. Simultaneous localization and mapping (SLAM) has become an important research field recently, by which the robot can generate a map while moving around. Both two-dimensional (2D) mapping and three-dimensional (3D) mapping methods have been developed greatly with high accuracy. However, 2D maps cannot reflect the space information of the environment and 3D mapping needs long processing time. Moreover, conventional SLAM methods based on grid maps take a long time to delete the moving objects from the map and are hard to delete the potential moving objects. In this paper, a 2D mapping method integrating with 3D information based on immobile area occupied grid maps is proposed. Objects in 3D space are recognized and their space information (e.g., shapes) and properties (moving objects or potential moving objects like people standing still) are projected to the 2D plane for updating the 2D map. By using the immobile area occupied grid map method, recognized still objects are reflected to the map quickly by updating the immobile area occupancy probability with a high coefficient. Meanwhile, recognized moving objects and potential moving objects are not used for updating the map. The unknown objects are reflected to the 2D map with a lower immobile area occupancy probability so that they can be deleted quickly once they are recognized as moving objects or start to move. The effectiveness of our method is proven by experiments of mapping under dynamic indoor environment using a mobile robot. more...

SUMMARY This paper focuses on mobile robots that can accompany a person, that is, it addresses how to control the position of the robot relative to the accompanied person according to the dynamic environment. The robot is expected to move side by side with the person in a normal situation, but a position in front or behind the person might be better if there are obstacles. The shape of the artificial potential field of the accompanied person is devised to smoothly control the robot position in a unified way. The Laplace potential method is also used subsidiarily to cope with extremely cluttered environments. Simulations and experiments in real space show the usefulness of the proposed method. more...

Darwin was the first one to assert that facial expressions are innate and universal, which are recognized across all cultures. However, recent some cross-cultural studies have questioned this assumed universality. Therefore, this paper presents an analysis of the differences between Western and East-Asian faces of the six basic expressions (anger, disgust, fear, happiness, sadness and surprise) focused on three individual facial regions of eyes-eyebrows, nose and mouth. The analysis is conducted by applying PCA for two feature extraction methods: appearance-based by using the pixel intensities of facial parts, and geometric-based by handling 125 feature points from the face. Both methods are evaluated using 4 standard databases for both racial groups and the results are compared with a cross-cultural human study applied to 20 participants. Our analysis reveals that differences between Westerns and East-Asians exist mainly on the regions of eyes-eyebrows and mouth for expressions of fear and disgust respectively. This work presents important findings for a better design of automatic facial expression recognition systems based on the difference between two racial groups. more...

Background The 1st nationwide survey by the Japanese Society of Pediatric Cardiology and Cardiac Surgery of acute or fulminant myocarditis (AMC/FMC) in children revealed that the survival rate of FMC was only 51.6%. The 2nd nationwide survey was performed to evaluate the recent outcomes of pediatric myocarditis.Methods and Results:Questionnaires regarding patients aged ≤18 years with AMC/FMC during the period from January 2006 to December 2011 were mailed. A total of 221 cases (age 6.5±5.3 years, 116 boys and 105 girls) were reported. There were 145 (65.6%) and 74 cases (33.5%) of AMC/FMC, respectively; the type of myocarditis was not reported in the remaining 2 cases (0.9%). Viruses were identified in 56 cases (25.3%), including coxsackie B in 9 and influenza A in 8. Histopathology by either endomyocardial biopsy or autopsy was obtained in 38 cases (19.2%). Intravenous immunoglobulin was effective in 49 (34.3%) of 143 cases. Steroid therapy was effective in 20 (32.8%) of 61 cases. Mechanical circulatory support was given in 54 cases (24.4%) and 94.2% of them were patients with FMC. The survival rates for the whole study population, acute myocarditis, and FMC were 75.6%, 91.0%, and 48.6%, respectively. Conclusions The survival rate of children with myocarditis was almost identical to that of 10 years ago. (Circ J 2016; 80: 2362-2368). more...

We present a case of fetal–neonatal acute myocarditis caused by coxsackievirus B3 infection in a term neonate. The condition manifested as high-grade atrioventricular (A-V) block prenatally. After delivery, various arrhythmias such as high-grade A-V block, ventricular tachycardia, and junctional ectopic tachycardia appeared, and we had difficulty managing these arrhythmias. This is the first report describing a case of acute myocarditis due to coxsackievirus infection presenting with fetal A-V block. This case is also unique in that it is extremely rare that various arrhythmias occur serially in one patient without left ventricular dysfunction. more...

This report describes six previously healthy infants with acute mitral valve chordal rupture. Although their initial symptoms were mild respiratory distress and fever, all the infants presented with acute progressive left heart failure and required urgent surgical repair. Mitral valve annuloplasty and mitral valve replacement were performed (for three patients each). Two patients died, both of whom had cardiac arrest and required resuscitation before surgery. Histologic examination of excised mitral valve leaflets showed infiltration of gram-positive bacteria in these two patients. All the patients were 4-6 months old, which may suggest underlying congenital factors. The authors believe early diagnosis and surgery are crucial as a life-saving measure for infants with acute mitral valve chordal rupture. more...

Two people usually walk through a corridor in a parallel position. However, they spontaneously switch their positions from the parallel to the cascade position when they pass oncoming people. We propose a method for enabling a robot to switch the parallel and the cascade positions autonomously with the movement of oncoming people and obstacles when it moves with a user in a daily environment. The robot uses two laser range finders to detect walls, the user's position, as well as surrounding people and obstacles. It autonomously decides whether to go on ahead or to give way to the user. Experimental results using a robot in a daily environment show that our method was effective. more...

It is likely that in the near future, human-symbiotic robots will share people's living spaces. Since there are many objects that can cause visual occlusion in these environments, situations in which a robot cannot see an object due to occlusion whereas a user can, and vice versa, will often occur. In such situations, ideally the human-symbiotic robot should be able to interact with the user while taking into consideration the differences between their fields of view. We anticipate that such a “considerate” robot will be friendlier and provide more pleasant interactions with users. In this paper, we aim to test this anticipation. First, we propose a robot that can estimate a user's and its own fields of view and thus behave appropriately due to being aware of the difference between their perceptions. The robot estimates the orientation of the user's head and the structure of its surrounding environment using a stereo camera. By combining these results, it can inform itself of the user's and its own fields of view: that is, what they can see and what they cannot see. Next, we carry out experimental subjective evaluations of the impressions that people gain during interaction with the proposed robot. Participants who observe the interactions are asked to subjectively evaluate their impressions of the robot's behaviors. The experimental results show that the proposed robot, which can guess what the user can see and understand the differences between their different viewpoints, is perceived as more “companionable.” This ability is likely to be one of the basic requirements for achieving interactions that people interpret as “friendly” with robots and other intelligent systems. more...

The effectiveness of transplacental drug therapy for prenatally diagnosed isolated congenital complete atrioventricular block (CCAVB) is controversial. Nine cases of prenatal isolated CCAVB were treated from 2002 to 2007. Ritodrine was administered transplacentally to all fetuses and betamethasone to those whose mothers tested positive for maternal anti-SSA/Ro antibodies. Six of the nine patients had an anti-SSA/Ro-positive mother and received transplacental betamethasone 4 mg/day at a median gestational age of 28 weeks (range, 24-31 weeks). No patients exhibited an improvement in the degrees of complete heart block, and one patient died in utero. No serious adverse events occurred. After the mean follow-up period of 1.7 +/- 1.3 years, all five patients treated with transplacental betamethasone experienced a good cardiac function, whereas one of the three patients not treated with transplacental betamethasone experienced cardiomyopathy and died at the age of 4 months. Pacemaker implantation was required for seven of the eight live-born infants. Transplacental betamethasone therapy for the patients with isolated CCAVB neither improved the degree of atrioventricular block nor decreased the rate of patients requiring pacemaker implantation, but it probably reduced the risk for the development of myocardial disease. more...

Photographs often have some people with closed eyes. A method to automatically output a best shot image in which all photographed members have open eyes is proposed. First a series of photographs (here 6 frames) is taken by using the continuous release function in commercial digital cameras. Blinking by each person is checked in each frame, and a frame in which all members have open eyes is selected. Blinking detection is carried out by calculating the normalized correlation between a 30 × 7 pixels open eyes template and input frames of reduced size. For a case where no frame exists in which all members have open eyes, the closed eye image is replaced by an open eye image obtained in a different frame. Experimental results for 18 photographs taken under various shooting conditions show the usefulness of the proposed method for automatically outputting a best shot image. more...

Recently, biologically inspired robots have been developed to acquire the capacity for directing visual attention to salient stimulus generated from the audiovisual environment. For the purpose of realizing this behavior, a general method is to calculate saliency maps to represent how much the external information attracts the robot's visual attention, where the audiovisual information and robot's motion status should be involved. In this paper, we represent a visual attention model where three modalities—audio information, visual information, and robot's motor status—are considered, because previous research has not considered all of them. First, we introduce a 2D density map, on which the value denotes how much the robot pays attention to each spatial location. Then we model the attention density using a Bayesian network where the robot's motion statuses are involved. Next, the information from both audio and visual modalities is integrated with the attention density map in integrate-fire neurons. The robot can direct its attention to the locations where the integrate-fire neurons are fired. Finally, the visual attention model is applied to make the robot select the visual information from the environment, and react to the content selected. Experimental results show that it is possible for robots to acquire the visual information related to their behaviors by using the attention model considering motion statuses. The robot can select its behaviors to adapt to the dynamic environment as well as to switch to another task according to the recognition results of visual attention. © 2006 Wiley Periodicals, Inc. Electr Eng Jpn, 158(2): 39–48, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20335 more...

A facial caricature expresses features of an individual face compactly and effectively. It is used in newspapers, magazines, home pages, and also used to represent an anthropomorphic agent and so on. This paper presents a method of synthesizing a caricature having higher flexibility in controlling individual shape features of various parts of a face, as well as features of arrangements and inclines of these parts. Firstly, an eigenspace is calculated for contour shape of each facial part such as the eyebrows, eyes, and mouth. In addition, an eigenspace for arrangements of various facial parts is obtained. Next, differences of the shapes and arrangements of the facial parts with the average face are calculated and then the orthogonal expansion to the basis vectors (eigenvectors) is carried out on these differences. Magnifying powers are determined according to the coefficients obtained by the orthogonal expansion and an emphasizing procedure is performed on eigenvectors. The difference between the slope of each facial part of the average face and that of an input face is emphasized using a quadratic function. A final caricature can be obtained by adding the average shape, average arrangement and average slope to these results. The effectiveness of the proposed caricature synthesis method is verified by subjective evaluation tests on synthesized facial caricatures. © 2004 Wiley Periodicals, Inc. Electron Comm Jpn Pt 3, 88(2): 65–76, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjc.20088 more...

This paper proposes a method to estimate sound source position by fusing auditory and visual information with Bayesian network in human-robot interaction. We firstly integrate multi-channel audio signals and a depth image about the environment to generate a likelihood map for sound source localization. However, this integration, denoted by “MICs", does not always lead to locate a sound source correctly. For correcting the failure in localization, we integrate the likelihood values generated from “MICs" and the skin-color distribution in an image according to the result of classifying audio signal into speech/non-speech categories. The audio classifier is based on support vector machine(SVM) and skin-color distribution is modeled by Gaussian mixture model (GMM). With the evidences given by MICs, SVM and GMM, we infer whether pixels in images correspond to a sound source or not according to the trained Bayesian network. Finally, experimental results are presented to show the effectiveness of the proposed method. more...

A facial caricature expresses features of an individual face summarily and has many uses for newspapers, magazines, home pages, agents, and the like. This paper presents a method of synthesizing a caricature having higher flexibility in controlling individual shape features of various parts of a face, as well as features of arrangements and inclines of these parts. In addition, it obtains eigenspaces for contours of facial parts such as the eyebrows, eyes, and mouth. It also obtains eigenspaces for arrangements of various facial parts. Next, it obtains differences of the shapes and arrangements of the facial parts with the average face and performs orthogonal expansion to the eigenspace bases (eigenvectors) on these differences. It determines magnifying power according to the coefficients obtained by orthogonal expansion and performs an emphasizing procedure on eigenvectors. The differences with the slopes of the facial parts of the average face are emphasized for the slopes of the facial parts using a second-order function. It obtains the shape of a caricature by adding the mean shape, mean arrangement, and mean slope to these results. The efficacy of the caricature synthesis method is verified by subjective evaluation tests on synthesized faces. © 2004 Wiley Periodicals, Inc. Electron Comm Jpn Pt 3, 87(8): 43–54, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjc.20088 more...

Recognizing characters on signboards in a scene would be very useful for translation, aquiring relevant information through the Internet, etc. This paper presents a method for extracting characters on signboards in arbitrary scene images that does not require any manual operations. First, we describe briefly the framework of an information handling system driven by characters on signboards in scene images. Next, a method for detecting signboard regions and individual character regions is investigated in consideration of signboards characteristics. The proposed method for detecting signboard regions is based on hierarchical clustering in the L* a* b* color space. Features of contour shape are examined to narrow the candidates of signboard regions. In addition, merging of adjacent candidate regions and rough checking of character existence are performed. Finally, each character on the signboard region is extracted by using binarization followed by horizontal and vertical projections. Experimental results from applying the method to 1000 various scene images show the effectiveness of the proposed method. more...

The ability to interact with multiple users as well as to recognize the ways in which people are interacting is essential for a robot participating in society. Forming shared attention is regarded as fundamental in improving the flexibility of human-robot interaction. This paper proposes an algorithm that enables shared attention between a robot and speakers in alternative conversational situations. We firstly present a microphone array technique and a method to combine auditory and visual information for estimating the physical location of the sound source. Secondly, the speaker is detected according to the linear combination of the result of sound source localization and the likelihood map representing the distribution of pixels having skin color. Finally, in the conversational situations, the speaker's focus of attention is alternatively detected and shared by the robot for upcoming communication based on the proposed algorithm. Several experimental results are presented that demonstrate the effectiveness of the proposed method. more...

In human-robot interaction, the ability to detect and share user’s attention is the minimal requirement for an intelligent robot, since it is very important for robot to know human’s internal state. Here we present an algorithm, which is based on face posture estimation and the spatiotemporal image processing, to calculate a saliency map in order to form share attention. After the face posture estimation, we introduce an elliptic cone to approximate the user’s visual field, whose axis is fitted to the user’s gaze line that is not necessary to be detected beforehand. A visual acuity map on the user’s retina can be yielded according to the formulization of human’s visual acuity. We calculate the saliency map in terms of recency-weighted average of visual acuity maps along time axis so that the dynamic scene (for example, the case that user’s gaze line is shifting to a new object or the gazed object is moving) can affect the saliency map calculation, as well as the moving image areas are tracked to propagate the value of the visual acuity map from the current frame to the next one. Finally, we use the saliency map to form share attention in human-robot interaction, and it is also manifested that it will be possible to detect the user’s attention by only considering face orientation even when the eyes cannot be observed clearly. more...

本研究では, 高密度実装に有利なBGAパッケージに対して, はんだ接合部の信頼度に大きな影響を与えるはんだ高さ, 濡れ角などのリフロー時の形状計算手法の調査を行った。はんだ形状予測に関する数種類の方法について調査を行い, 実験結果と比較することによって各計算手法の妥当性について検討を行った。また, これらの計算手法の1つである差分法に, 直交表を用いた応答曲面法を適用することによって, はんだ高さ, 濡れ角を簡易に計算できる近似式多項式の作成を行った。次に, リフロー時のはんだ凝固時に発生する残留応力を評価するため, はんだ凝固時の基板変形を有限要素法, 実測により評価した。 more...

The ray-based approach is powerful and useful for the description of 3-D images because of its neutrality to all types of 3-D displaying technologies This approach has been developed in order to reproduce the whole visual data captured at the transmitter However, for the purpose of augmented reality, not only is the reproduction of real visual data essential, but also the synthesis of virtual visual data For example, you may want to change the lightening condition of a scene which has already been captured in some photographs The goal of this work is to synthesize a virtual scene, in which we can easily move light sources The key feature is that the virtual scene is synthesized only from the photographs. From this point of view, this paper extends the concept of the ray-based description of 3-D visual data in order to cope with virtual light sources Experimental results show the potential applicability of this method to the augmented spatial communication systems. more...

This paper proposes a method of estimating multiview camera parameters for cases in which the structure of objects is unknown. The proposed method uses multiple rectangles in the 2-D images captured with the same focal length as the keys to estimate camera parameters. In this method, the 3-D coordinates of rectangles are first estimated from all images by using the characteristic of rectangles and the least squares method. Then, all camera parameters are estimated by using the estimated 3-D coordinates of rectangles and the least squares method. Finally, all parameters, that is, 3-D coordinates of rectangles and camera parameters, are corrected to minimize the errors in all images. Experimental results show that the proposed method gives good estimations of the multiview camera parameters required to obtain ray information for cases in which the shape of objects is unknown. This means that ray information can be acquired by using one ordinary camera instead of a special camera controlled by computer. more...

In order to achieve flexible 3-D visual communication, we have proposed a light ray based describing method of 3-D images. Furthermore, we have proposed a new concept of “3-D Space Coding” to describe and transmit the entire visual data of a 3-D space. Because the amount of spatial data is huge, it must be compressed for transmission and for easy handling by computers. In order to synthesize an image from one viewpoint, it is not necessary that all of the compressed data are expanded. Only the data essential for each view should be expanded. In this paper, the concept of “3-D Space Coding” is explained and a method for expanding the compressed light ray data locally is discussed in detail. Experimental results show the potential applicability of the proposed method to deal with larger space by local expansion of compressed light ray data. more...

Video network is beginning to have various kinds of applications such as using a vertical blanking interval. Model-based coding is suitable for the narrow band network. Interactive model-based image coding, which had been developed for non-realtime environment, needs to be specified by the number and the precision of interactive operations. This paper first analyzes the noise in input feature points during the global motion parameter detection. Then a new structure filter for reducing the noise in the feature points on a facial wireframe model is developed. The structure filter keeps original facial shape composed of feature points and reduces variation in the mutual distance between the feature points. In evaluating the precision for applying the least-squares method for detecting depth and global motion parameters, the number of conditions of input data is considered from the point of variance of error of the estimated values. Based on the structure filter with the precision evaluation, the allowance error in the interactive operation for the encoding process is specified by the pixel accuracy for feature point position. more...

あらまし3次元空間における膨大な光線情報に対して, 1台のカメラの位置を逐次的に制御しながら光線情報を効率的にサンプリングする手法を提案する.すでに取得された光線情報から3次元空間がどの程度正確に補間合成され得るかを予測し, 補間が困難な視点位置から優先的に光線情報を取得する.実際に視点探索の実験を行い、本手法の実現可能性を示す.

First, this paper introduces the concept of “Integrated 3-D Visual Communication”. The key feature in this concept is the display-independent neutrality and flexibility of the representation of visual data. Secondly, a ray-based approach is examined in order to realize this concept. The advantage of a ray-based approach is that any view can be synthesized from ray data independently of any geometric representations. All the visual data is represented by a set of ray data which is defined in five-dimensional data space. Assuming that rays go straight on without any variations in the direction of propagation, any individual ray data can be efficiently stored in the fewer dimensions. This paper proposes and formulates three methods for projecting five-dimensional data space onto a space with fewer dimensions. The experimental results show how the proposed methods could be used in the next-generation 3-D image communication and photo-realistic virtual reality systems. more...

This paper proposes a new method of describing spatiotemporal images based on the concept of structured abstract index images. In spatiotemporal images, each region in an image sequence forms a tube. An original image sequence can be reconstructed by cutting out the sequence of cross sections from the group of tubes in these images. That is, a moving image sequence can be described compactly by the group of tubes. This paper first discusses the method of approximating static contours by Bezier curves. Approximation of surface tubes by Bezier surface is examined in detail. A problem with this method is that it does not work well if shape of the cross section changes considerably along the time axis. This problem can be solved by growing a new Bezier surface from passing points of Bezier curve and by combining the different Bezier surfaces. more...