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101.
Lu Yang Tomohiro Yendo Mehrdad Panahpour Tehrani Toshiaki Fujii Masayuki Tanimoto 《Journal of Visual Communication and Image Representation》2010,21(5-6):542-560
In this paper, we present a new view synthesis method in multiview camera configurations of Free viewpoint TV (FTV) where potential depth errors are considered. The emphasis is on the artifacts eliminating for photorealistic synthesis especially near object boundaries. In contrast to conventional techniques which ignore geometry errors, we first categorize the artifact cases and depth modes. Furthermore, this paper infers the complementarity principle of the artifacts from left and right references. This complementarity guarantees the effectiveness of our reliability-based synthesis. The reliability reasoning is crucial for artifacts reduction. The reliable and unreliable areas from different views can be correctly labeled. Then artifacts caused by unreliable pixels from one reference can be replaced by the reliable pixels from the other reference. As a final result, artifacts of novel view are demonstrated to be significantly reduced on different multiview sequences. 相似文献
102.
Takehiko Watanabe Masataka ShirokiAtsushi Yanagisawa Tomohiro Sasaki 《Journal of Materials Processing Technology》2010,210(12):1646-1651
Authors investigated the effect of ultrasonic vibration on the solidification microstructure and mechanical properties of the weld metal of ferritic stainless steel by introducing directly ultrasonic vibration into the weld molten pool using ultrasonically vibrating filler metal. The main results obtained in this study are as follow. 相似文献
103.
LQ Jia M Osada C Ishioka M Gamo S Ikawa T Suzuki H Shimodaira T Niitani T Kudo M Akiyama N Kimura M Matsuo H Mizusawa N Tanaka H Koyama M Namba R Kanamaru T Kuroki 《Canadian Metallurgical Quarterly》1997,19(4):243-253
We have screened the p53 status of 156 human cell lines, including 142 tumor cell lines from 27 different tumor types and 14 cell lines from normal tissues by using functional analysis of separated alleles in yeast. This assay enables us to score wild-type p53 expression on the basis of the ability of expressed p53 to transactivate the reporter gene HIS3 via the p53-responsive GAL1 promotor in Saccharomyces cerevisiae. Of 142 tumor cell lines, at least 104 lines (73.2%) were found to express the mutated p53 gene: 94 lines (66.2%) were mutated in both alleles, three lines (2.1%) were heterozygous, and no p53 cDNA was amplified from seven lines (4.9%). Of the 14 cell lines originating from normal tissues, all the transformed or immortalized cell lines expressed mutant p53 only. Yeast cells expressing mutant p53 derived from 94 cell lines were analyzed for temperature-sensitive growth. p53 cDNA from eight cell lines showed p53-dependent temperature-sensitive growth, growing at 30 degrees C but not at 37 degrees C. Four temperature-sensitive p53 mutations were isolated: CAT-->CGT at codon 214 (H214R), TAC-->TGC at codon 234 (Y234C), GTG-->ATG at codon 272 (V272M), and GAG-->AAG (E285K). Functionally wild-type p53 was detected in 38 tumor cell lines (26.8%) and all of the diploid fibroblasts at early and late population doubling levels. These results strongly support the previous findings that p53 inactivation is one of the most frequent genetic events that occurs during carcinogenesis and immortalization. 相似文献
104.
S Hirokawa I Yamashita Y Kuroki Y Yamashita M Fujimaki K Aoyama J Murakami 《Canadian Metallurgical Quarterly》1998,28(3):349-354
OBJECTIVE: The clinical characteristics and outcomes of endometrial cancer patients 45 years of age and younger were compared with those of patients older than 45 years of age. METHODS: We performed a cross-sectional study of 301 consecutive endometrial cancer patients referred to our center from 1989 to 1994. Of the 289 patients eligible for study, 40 were 45 years of age or younger (group A) and 249 were older than 45 years of age (group B). RESULTS: The majority of patients in both groups presented with stage I disease. Of the women with stage I disease, patients in group A were more likely than those in group B to have low-grade disease localized to the endometrium (P < .001; relative prevalence 3.39; confidence interval [CI] 1.88, 6.12). However, the distribution of stages I to IV overall was the same for the two groups (P = .269). Although univariate analysis revealed that 11% of the patients in group A and 2% in group B had synchronous ovarian malignancies (P = .007; relative prevalence 5.42; CI 1.39, 21.14), multivariate logistic regression found that nulliparity, not age, was an independent risk factor for synchronous ovarian malignancy (P = .017; relative prevalence 6.15; CI 1.52, 25.61). There were no statistically significant differences by age in the prevalence of high-risk endometrial histology (serous and clear cell carcinoma) or in survival. CONCLUSION: The overall distribution of tumor stage and survival were the same for the younger and older women; this finding contradicts previous reports that suggest that young women with endometrial cancer are at lower risk. Additionally, nulliparity, which occurs with a higher prevalence in younger women who develop endometrial cancer, is associated statistically with the development of synchronous ovarian malignancies. 相似文献
105.
Tomohiro Nakai Nobuyuki Kondo Koichi Kise Keinosuke Matsumoto 《Electrical Engineering in Japan》2008,165(2):60-68
In order to make collaborative business activities fruitful, it is essential to know characteristics of organizations and persons in more details and to gather information relevant to the activities. In this paper, we describe a notion of “information recycling” that actualizes these requirements by analyzing documents. The key of recycling information is to utilize annotations on documents as clues for generating user profiles and for weighting contents in the context of the activities. We also propose a method of extracting annotations on paper documents just by pressing one button with the help of techniques of camera‐based document image analysis. Experimental results demonstrate that it is fundamentally capable of acquiring annotations on paper documents on the condition that their electronic versions without annotations are available for the processing. © 2008 Wiley Periodicals, Inc. Electr Eng Jpn, 165(2): 60–68, 2008; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20516 相似文献
106.
Soluble polyimides (PIs) were prepared as random or multiblock types with 4,4′‐(hexafluoroisopropylidene) diphthalic anhydride (6FDA) and 3,3′,4,4′‐biphenyltetracarboxylic dianhydride (s‐BPDA) as acid dianhydride components and 4,4′‐bis(m‐aminophenoxy) diphenyl sulfone (m‐BAPS) as a diamine component by a one‐pot process and used to improve the brittleness of the cyanate ester resin. Random‐type PIs were more effective as modifiers than multiblock‐type PIs. The morphologies of the modified resins depended on PI structure, molecular weight, and concentration. The most effective modification of the cyanate ester resin was attained because of a heterogeneous phase structure composed of a flat matrix phase and phase‐inverted structures of the modified resin; a 15 wt % inclusion of a random PI (weight‐average molecular weight = 63,400) composed of 6FDA, s‐BPDA, and m‐BAPS (0.5/0.5/1.0 molar ratio) led to a 65% increase in the fracture toughness for the modified resin with a slight loss of flexural strength and a retention of flexural modulus and glass‐transition temperature, compared with the values for the unmodified resin. Water absorptivity of the modified resin was comparable to that of the unmodified resin up to 400 h, and then, water absorption of the modified resins increased considerably. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 1–11, 2003 相似文献
107.
High degree posterior rotational osteotomy was performed on 31 hips with extensive osteonecrosis that were outside of Sugioka's indication. Among them, 18 hips of 13 patients were reviewed at 24 to 94 months (mean, 42 months). The remaining 13 hips were excluded because the followup was less than 2 years. All hips had less than 1/3 of the posterior area intact preoperatively, which is out of the indication for traditional anterior rotational osteotomy. The posterior rotation applied to the femoral head was 130 degrees to 180 degrees (mean, 138 degrees ). Furthermore, 10 degrees to 25 degrees of intentional varus position was added to the rotation (mean, 15.8 degrees). The preoperative intact articular surface of the loaded portion of the femoral head was 0% to 40% (mean, 6.9%) on anteroposterior radiograph, and it was extended postoperatively to a mean of 80.3% (range, 53%-100%). Collapse was prevented in 17 hips that have remained pain free. The remaining 1 hip sustained secondary collapse and joint narrowing. Mean flexion was 105 degrees and abduction was 20 degrees. Postoperative angiography of 9 hips and bony scintigraphy of 17 hips indicated no findings implying impairment of blood supply. Despite a relatively short term experience, it is concluded that this technique was effective in the treatment of large necrotic lesions, especially for young patients. 相似文献
108.
S Hamanaka T Hata Y Tsushima M Matsumoto K Fujiwara H Furukawa K Kuroki Z Masuda 《Canadian Metallurgical Quarterly》1997,50(10):879-882
An episode of malignant hyperthermia occurring in a 42-year-old man undergoing hypothermic cardiopulmonary bypass is reported. Malignant hyperthermia is a syndrome initiated by a hypermetabolic state of skeletal muscle. A patient presented for correction of an acyanotic tetralogy of Fallot. The coincidental usage of hypothermic cardiopulmonary bypass obscured the classical presenting sings and symptoms of the malignant hyperthermia. And the disease of tetralogy of Fallot made the syndrome difficult to manage. Although the clinical diagnosis of malignant hyperthermia is difficult to be confirmed, when it is suspected, it is prudent for the case to be initially treated as malignant hyperthermia. 相似文献
109.
Masaaki Yokoyama Tomohiro Zaita 《International journal for numerical methods in engineering》1992,35(6):1277-1288
In order to obtain accurate results and to reduce computation time, we have proposed in this paper a new strategic method, where quadratic elements are used at the corner points and linear elements at the points off the corner points. A computer program using this method has been developed and applied to several problems of various shapes. The usefulness of this method was illustrated by the application results. 相似文献
110.
Tatsuyuki Kawamura Tomohiro Fukuhara Hideaki Takeda Yasuyuki Kono Masatsugu Kidode 《Personal and Ubiquitous Computing》2007,11(4):287-298
In this paper we propose an object-triggered human memory augmentation system named “Ubiquitous Memories” that enables a user
to directly associate his/her experience data with physical objects by using a “touching” operation. A user conceptually encloses
his/her experiences gathered through sense organs into physical objects by simply touching an object. The user can also disclose
and re-experience for himself/herself the experiences accumulated in an object by the same operation. We implemented a prototype
system composed basically of a radio frequency identification (RFID) device. Physical objects are also attached to RFID tags.
We conducted two experiments. The first experiment confirms a succession of the “encoding specificity principle,” which is
well known in the research field of psychology, to the Ubiquitous Memories system. The second experiment aims at a clarification
of the system’s characteristics by comparing the system with other memory externalization strategies. The results show the
Ubiquitous Memories system is effective for supporting memorization and recollection of contextual events. 相似文献