Engineering criticality analysis on an offshore structure using the first- and second-order reliability method

AbstractDue to the uncertainties related to the flaw assessment parameters, such as flaw size, fracture toughness, loading spectrum and so on, the probability concept is preferred over deterministic one in flaw assessment. In this study, efforts have been made to develop the reliability based flaw assessment procedure which combines the flaw assessment procedure of BS7910 and first- and second-order reliability methods (FORM/SORM). Both crack length and depth of semi-elliptical surface crack at weld toe were handled as random variable whose probability distribution was defined as Gaussian with certain means and standard deviations. Then the limit state functions from static rupture and fatigue perspective were estimated using FORM and SORM in joint probability space of crack depth and length. The validity of predicted limit state functions were checked by comparing it with those obtained by Monte Carlo simulation. It was confirmed that the developed methodology worked perfectly in predicting the limit state functions without time-consuming Monte Carlo simulation

Indexing and Retrieving Photographic Images Using a Combination of Geo-Location and Content-Based Features

This paper presents a novel method that automatically indexes searches for relevant images using a combination of geo-coded information and content-based visual features. Photographic images are labeled with their corresponding GPS (Global Positioning System) coordinates and UTC time (Coordinated Universal Time) information at the moment of capture, which are then utilized to create spatial and temporal indexes for photograph retrieval. Assessing the performance in terms of average precision and F-score with real-world image collections revealed that the proposed approach significantly improved and enhanced the retrieval process compared to searches based on visual content alone. Combining content and context information thus offers a useful and meaningful new approach to searching and managing large image collections

Ultraviolet photodepletion spectroscopy of dibenzo-18-crown-6-ether complexes with alkali metal cations

Ultraviolet photodepletion spectra of dibenzo-18-crown-6-ether complexes with alkali metal cations (M+-DB18C6, M = Cs, Rb, K, Na, and Li) were obtained in the gas phase using electrospray ionization quadrupole ion-trap reflectron time-of-flight mass spectrometry. The spectra exhibited a few distinct absorption bands in the wavenumber region of 35450−37800 cm^(−1). The lowest-energy band was tentatively assigned to be the origin of the S_0-S_1 transition, and the second band to a vibronic transition arising from the “benzene breathing” mode in conjunction with symmetric or asymmetric stretching vibration of the bonds between the metal cation and the oxygen atoms in DB18C6. The red shifts of the origin bands were observed in the spectra as the size of the metal cation in M^+-DB18C6 increased from Li^+ to Cs^+. We suggested that these red shifts arose mainly from the decrease in the binding energies of larger-sized metal cations to DB18C6 at the electronic ground state. These size effects of the metal cations on the geometric and electronic structures, and the binding properties of the complexes at the S_0 and S_1 states were further elucidated by theoretical calculations using density functional and time-dependent density functional theories

Substroke Matching by Segmenting and Merging for Online Korean Cursive Character Recognition

The Korean character is composed of several alphabets in two-dimensional formation and the total number of Korean characters exceeds eleven thousand. Therefore, the previous approaches to Korean cursive characters pay most of their attention to segmenting a character into alphabets accurately. However, it is difficult because the boundaries of alphabets are not apparent in most cases. We propose an alphabet-based method without assuming accurate alphabet segmentation. In the proposed method, a cursive character is segmented into substrokes by a set of segmenting conditions. Then it is matched with the reference substrokes generated from alphabet models and ligatures by segmenting and merging in the process of recognition. Among substrokes, a certain substroke can be either an alphabet itself a part of alphabet or a composite of the alphabet and ligature. We applied the proposed method to 5000 Korean characters and got the result of 83.4% for the first rank and 89.2% for the top 5 result candidates with the speed of 0.17 seconds on average per character on a PC which uses Intel Pentium 90 Mhz CPU

Recombinant lignin peroxidase-catalyzed decolorization of melanin using in-situ generated H2O2 for application in whitening cosmetics

Lignin peroxidase has high potential as ingredient in skin whitening cosmetics due to its high redox potential to oxidize recalcitrant melanin. Currently crude mixtures of lignin peroxidase from fungal fermentation are usually applied to cosmetics due to the intrinsic difficulties of expression and purification. However, the present study focused on heterologous expression and purification of lignin peroxidase isozyme H8 (LiPH8) from Phanerochaete chrysosporium and was further used for melanin decolorization. Results revealed that the optimum pH for melanin decolorization using LiPH8 was obtained at pH???4.0. The intermittent feeding of hydrogen peroxide (H2O2) was effectively elevating melanin decolorization efficiency up to 73%, since excessive H2O2 inactivated LiPH8. For cosmetic application, intermittent feeding of H2O2 is not feasible, thus glucose oxidase (GOx) from Aspergillus niger was employed for in-situ generation of H2O2. By optimizing the GOx and glucose concentrations, a melanin decolorization efficiency up to 63.3????????2.4% was obtained within 1???h and continued to 84.0????????1.8% in 8???h. Conclusively, lignin peroxidase-catalyzed decolorization of melanin with in-situ generated H2O2 revealed a promising approach for whitening cosmetics applications