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Lining deformation, cracks, and spalling are the most crucial items to be checked during structural safety inspections of tunnels in operations. These three faults are often cited as indicators of structural safety and are used to determine the need for maintenance or repair operations. However, existing evaluation criteria do not account for how the quality of a tunnel's lining structure varies over its life cycle. The present study examined the 30-year construction and repair records of a highway tunnel in southeastern Taiwan. This study also quantitatively analyzed the relationships among tunnel displacement, lining cracks, and concrete spalling. The results revealed that compared with the associated displacement, tunnel deformation after overall profile translation was compensated for was more representative of tunnel structural safety and lining spalling potential. Specially, when the cumulative tunnel deformation reaches 1 % equivalent radius and when the deformation rate reaches 40E-6/year, the potential for lining spalling is notable. Concrete spalling is common near closed, radial, acute-angle intersecting cracks in a tunnel and also in the vicinity of circumferential construction joints. If a tunnel intersects the potential sliding surface of a moving mass on a slope, the vicinity of this intersection should be evaluated for concrete spalling. The spalling potential of concrete increases with the crack density. For a tunnel in operations, crack densities of 1.0 and 1.5 m/m2 and associated change rates reach 2.0 and 3.0 m/m2/year can be applied as thresholds for grading moderate and high spalling potential, respectively, in the tunnel lining. [ABSTRACT FROM AUTHOR]

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.ydbio.2009.06.003 Byline: Cheng-chen Huang (a), Tai-Chuan Wang (a), Bo-Hung Lin (a)(b), Yi-Wen Wang (a), Stephen L. Johnson (c), John Yu (a)(d) Keywords: Zebrafish; Vascular plexus; Collagen IX; Actinotrichia; Fin Abstract: Capillary plexuses form during both vasculogenesis and angiogenesis and are remodeled into mature vessel types and patterns which are delicately orchestrated with the sizes and shapes of other tissues and organs. We isolated a zebrafish mutation named prp (for persistent plexus) that causes persistent formation of vascular plexuses in the caudal fins and consequent mispatterning of bony fin rays and the fin shape. Detailed analyses revealed that the prp mutation causes a significant reduction in the size and dramatic structural defects in collagen II-rich extracellular matrices called actinotrichia of both embryonic finfolds and adult fins. prp was mapped to chromosome 19 and found to encode the zebrafish collagen9[alpha]1 (col9[alpha]1) gene which is abundantly expressed in developing finfolds. A point mutation resulting in a leucine-to-histidine change was detected in the thrombospondin domain of the col9[alpha]1 gene in prp. Morpholino-mediated knockdown of col9[alpha]1 phenocopied the prp small-finfold phenotype in wild-type embryos, and an injection of plasmids containing the col9[alpha]1 cDNA into prp embryos locally restored the finfold size. Furthermore, we found that osteoblasts in prp mutants were mispatterned apparently following the abnormal vascular plexus pattern, demonstrating that blood vessels play an important role in the patterning of bony rays in zebrafish caudal fins. Author Affiliation: (a) Institute of Cellular and Organismic Biology, Academia Sinica, 128 Academia Road, Section 2, Nankang, Taipei 115, Taiwan (b) Institute of Bioscience and Biotechnology, National Taiwan Ocean University, Keelung, Taiwan (c) Department of Genetics, Washington University Medical School, St. Louis, MO, USA (d) Genomics Research Center, Academia Sinica, Taipei, Taiwan Article History: Received 6 April 2009; Revised 30 May 2009; Accepted 2 June 2009

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.techfore.2007.01.001 Byline: Tai-Yue Wang, Shih-Chien Chien, Chiang Kao Keywords: Technology development; National competitiveness; Economic performance; Human resources; Management capability Abstract: Technology development (TD) plays a key role in national competitiveness (NC) by giving a country a competitive edge in our age of information. Lots of researchers have focused on specific areas of TD, such as technology transfer, technology acquisition, and technology management, in most of developed countries. To our knowledge, however, they have seldom discussed the influence of TD on other categories of NC and vice-versa in developing and less-developed countries. In this study, we examine the influences of each category of NC of TD. Southeast Asian countries are divided into three patterns by means of a cluster analysis. The results show that Singapore, Malaysia, Thailand, and Laos have the same rank on measures of TD and NC. Singapore, Thailand, the Philippines, and Laos have the same rank on measures of TD and Economic Performance. Malaysia and Thailand have the same rank on measures of TD and Management Capability. In contrast, the TD performance of Southeast Asian countries is worse than the human resources performance because of their insufficient human resources assigned to R&D. Furthermore, based on a strategic grid for comparing the relative performance, four types of country and their achievements are discussed. Singapore outperforms all Southeast Asian countries. Malaysia and Thailand have to leverage their TD resources in order to enhance their NC. The other countries are still hindered in developing the determinants of their NC. Finally, our study offers a path to the identification of how countries of each pattern should supplement their insufficient capabilities, and what are the most important issues that need to be addressed in retuning their TD policies in order to enhance their NC. Author Affiliation: Department of Industrial and Information Management, National Cheng Kung University Tainan, Tainan, Taiwan Article History: Received 28 March 2006; Revised 27 December 2006; Accepted 3 January 2007

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.ejor.2005.08.020 Byline: Tai-Yue Wang, Chien-Yu Huang Keywords: Forecasting; Taguchi method; Orthogonal array Abstract: To satisfy the volatile nature of today's markets, businesses require a significant reduction in product development lead times. Consequently, the ability to develop precise product sales forecasts is of fundamental importance to decision-makers. Over the years, many forecasting techniques of varying capabilities have been introduced. The precise extent of their influences, and the interactions between them, has never been fully clarified, although various forecasting factors have been explored in previous studies. Accordingly, this study adopts the Taguchi method to calibrate the controllable factors of a forecasting model. An L.sub.9(3.sup.4) inner orthogonal array is constructed for the controllable factors of data period, horizon length, and number of observations required. An experimental design is then performed to establish the appropriate levels for each factor. At the same time, an L.sub.4(2.sup.3) outer orthogonal array is used to consider the inherited parameters of forecasting method as the noise factors of Taguchi method simultaneously. An illustrated example, employing data from a power company, serves to demonstrate the thesis. The results show that the proposed model permits the construction of a highly efficient forecasting model through the suggested data collection method. Author Affiliation: Department of Industrial and Information Management, National Cheng Kung University, Tainan 701, Taiwan Article History: Received 23 August 2004; Accepted 3 August 2005

Purpose: Fibrous dysplasia (FD) is a benign condition in which normal cancellous bone is replaced by immature woven bone and fibrous tissue. The present study aimed to estimate and compare the 3-dimensional (3D) accuracy of bone contouring surgery for zygomaticomaxillary FD performed using virtual planning and surgical navigation versus surgeon's intraoperative assessment.Patients and Methods: This is a retrospective cross-sectional study. Patients with zygomaticomaxillary FD who underwent bone contouring surgery between 2012 and 2019 were reviewed. They were divided into 2 groups: group A underwent bone contouring surgery using virtual planning and surgical navigation, and group B underwent bone contouring surgery by surgeon's intraoperative assessment. The predictor variable was surgical technique. The other variables were gender, age, and operative region. The primary outcome variable was 3D accuracy, which was indicated by root mean square, calculated as a measure of the deviation of the postoperative computed tomography from the preoperative virtual plan. The other outcome variables were patient satisfaction with the outcome by self-evaluation score and operative times. Correlation analysis between the predictor variables and outcome variables was performed.Results: The sample comprised 24 patients (17 males and 7 females, mean age, 25.7 ± 10.45 years), 13 patients in group A and 11 patients in group B. The mean root mean square was significantly lower in group A than in group B (P = .007). Patient satisfaction with facial symmetry was significantly better in group A (P = .015). Mean operative time was comparable between the 2 groups (P = .918). Surgical technique (P = .011) and operative region (P = .01) were significant influence factors in 3D accuracy of surgery.Conclusions: Virtual planning and surgical navigation can significantly improve the 3D accuracy and patient satisfaction of bone contouring surgery for zygomaticomaxillary FD, without prolonging operative time. [ABSTRACT FROM AUTHOR]

Purpose: The anterolateral thigh flap (ALTF) volume will decrease over time after surgery. We measured and identified the risk factors for postoperative volume changes in the ALTF.Materials and Methods: We designed and performed a retrospective cohort study of patients who had undergone reconstruction of oral and maxillofacial defects using ALTFs at the Department of Oral and Maxillofacial Surgery, Peking University School and Hospital of Stomatology from June 2012 to December 2018. We measured the volume of the ALTFs at 1, 3, 6, 12, and 24 months postoperatively; the flap volume at 1 month postoperatively was taken as the baseline. The primary outcome variables were the residual ALTF rates at 3, 6, 12, and 24 months postoperatively, defined as the ratio between the present volume at each month and at baseline. The primary predictor variables were the clinical variables that might be associated with ALTF volume loss. Descriptive and bivariate statistics were computed, and the P value for statistical significance was set at ≤ .05.Results: The sample included 70 subjects with a mean age of 53.8 years (46 men and 24 women). The postoperative residual rates at 3, 6, 12, and 24 months were 72.3, 69.0, 67.9, and 68.7%, respectively, of the baseline volume. The use of postoperative radiotherapy (P < .01) and low body mass index (BMI; P = .006) were significantly associated with postoperative ALTF volume loss.Conclusions: The results of the present study suggest that ALTF volume shrinkage mainly occurs within 6 months postoperatively and that postoperative radiotherapy and a low BMI are risk factors for volume loss. Overcorrection should be performed to account for the shrinkage of ALTFs, and postoperative nutrition management is important to avoid ALTF volume loss. [ABSTRACT FROM AUTHOR]