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Department of Logistics2008-2009 > Academic research: refereed > Publication in refereed journalAccepted ManuscriptPublishe
Engineering metal oxide nanostructures for the fiber optic sensor platform
This paper presents an effective integration scheme of nanostructured SnO2 with the fiber optic platform for chemical sensing applications based on evanescent optical interactions. By using a triblock copolymer as a structure directing agent as the means of nano-structuring, the refractive index of SnO2 is reduced from >2.0 to 1.46, in accordance with effective medium theory for optimal on-fiber integration. Hightemperature stable fiber Bragg gratings inscribed in D-shaped fibers were used to perform real-time characterization of optical absorption and refractive index modulation of metal oxides in response to NH3 from the room temperature to 500°C. Measurement results reveals that the redox reaction of the nanostructured metal oxides exposed to a reactive gas NH3 induces much stronger changes in optical absorption as opposed to changes in the refractive index. Results presented in this paper provide important guidance for fiber optic chemical sensing designs based on metal oxide nanomaterials. © 2014 Optical Society of America
A new hybrid approach to human error probability quantification-applications in maritime operations
Human Reliability Analysis (HRA) has always been an essential research issue in safety critical systems. Cognitive Reliability Error Analysis Method (CREAM), as a well-known second generation HRA method is capable of conducting both retrospective and prospective analysis, thus being widely used in many sectors. However, the needs of addressing the use of a deterministic approach to configure common performance conditions (CPCs) and the assignment of the same importance to all the CPCs in a traditional CREAM method reveal a significant research gap to be fulfilled. This paper describes a modified CREAM methodology based on an Evidential Reasoning (ER) approach and a Decision Making Trial and Evaluation Laboratory (DEMATEL) technique for making human error probability quantification in CREAM rational. An illustrative case study associated with maritime operations is presented. The proposed method is validated by sensitivity analysis and the quantitative analysis result is verified through comparing the real data collected from Shanghai coastal waters. Its main contribution lies in that it for the first time addresses the data incompleteness in HEP, given that the previous relevant studies mainly focus on the fuzziness in data. The findings will provide useful insights for quantitative assessment of seafarers' errors to reduce maritime risks due to human errors
A systematic simulation methodology for LNG ship operations in port waters: a case study in Meizhou Bay
With the increment for liquefied natural gas (LNG) demand, LNG carriers are becoming larger in size. The operational safety of the carriers and the associated terminals is increasingly attracting attention. This is particularly true when a large LNG vessel approaches a terminal, requiring a detailed investigation of ship handling in port waters, especially in certain unusual cases. A full mission simulator provides an effective tool for research and training in operations of both port terminals and ships. This paper presents an experimental design methodology of the full mission simulation. The details as to how the simulation is achieved are described, and the simulation strategies applicable to LNG ships are specified. A typical case study is used to demonstrate and verify the proposed design methodology. The proposed methodology of the full mission simulation provides guidance for port safety research, risk evaluation and seafarer training. © 2017 Institute of Marine Engineering, Science & Technolog
A dual cube hashing scheme for solving LPP integrity problem
In digital forensics, data stored in a hard disk usually contains valuable evidence. Preserving the integrity of the data in the hard disk is a critical issue. A single hash value for the whole hard disk is not appropriate as the investigation may take a long time and latent sector errors (LSEs) (bad sectors due to media imperfection, for example) which cause a sector suddenly unreadable will make the hash value inconsistent. On the other hand, using a hash per sector may need to store a lot of hash values. Previous research has been conducted to use fewer hash values, but can resist some of LSEs to decrease the number of unverifiable sectors even if there are LSEs. This integrity problem is more complicated in the presence of Legal Professional Privileged (LPP) data inside a seized hard disk in digital forensic as the hard disk has to be cloned once seized and the original hard disk will be sealed after cloning. Hash values need to be computed during this cloning process. However, the cloned copy will be returned to the suspect for the deletion of LPP data before the investigator can work on the sanitized copy. Thus, the integrity of unmodified sectors has to be verified using the hash values computed based on the original hard disk. This paper found that existing schemes are not good enough to solve the integrity problem in the presence of both LSEs and deletion of LPP data. We then propose the idea of a "Dual Cube" hashing scheme to solve the problem. The experiments show the proposed scheme performs better than the previous schemes and fits easily into the digital forensic procedure. © 2011 IEEE.published_or_final_versionThe 6th International Workshop on Systematic Approaches to Digital Forensic Engineering In conjunction with the IEEE Security and Privacy Symposium (IEEE/SADFE 2011), Oakland, CA., 26 May 2011. In IEEE/SADFE Proceedings, 2011, p. 1-
Different mechanisms of cis-9,trans-11- and trans-10,cis-12- conjugated linoleic acid affecting lipid metabolism in 3T3-L1 cells
Conjugated linoleic acid (CLA) has been shown to reduce body fat mass in various experimental animals. It is valuable to identify its influence on enzymes involved in energy expenditure, apoptosis, fatty acid oxidation and lipolysis. We investigated isomer-specific effects of high dose, long treatment of CLA (75.4 Μmol/L, 8 days) on protein and gene expression of these enzymes in cultured 3T3-L1 cells. Proteomics identified significant up- or down-regulation of 52 proteins by either CLA isomer. Protein and gene expression of uncoupling protein (UCP) 1, UCP3, perilipin and peroxisome proliferator-activated receptor (PPAR) α increased whereas UCP2 reduced for both CLA isomers. And eight-day treatment of trans-10,. cis-12 CLA, but not cis-9,. trans-11 CLA, significantly up-regulated protein and mRNA levels of PKA (P<05), CPT-1 and TNF-α (P<01). Compared to protein expression, both isomers did not significantly influence the mRNA expression of HSL, ATGL, ACO and leptin. In conclusion, high-dose, long treatment of cis-9,. trans-11 CLA did not promote apoptosis, fatty acid oxidation and lipolysis in adipocytes, but may induce an increase in energy expenditure. trans-10,. cis-12 CLA exhibited greater influence on lipid metabolism, stimulated adipocyte energy expenditure, apoptosis and fatty acid oxidation, but its effect on lipolysis was not obvious. © 2010 Elsevier Inc.postprin
Hepatitis B Virus Core Promoter Double Mutations (A1762T, G1764A) Are Associated with Lower Levels of Serum Dihydrolipoyl Dehydrogenase
Published by S. Karger AG, BaselObjectives: The aim of this study was to identify serum proteins with differential concentrations between hepatocellular carcinoma (HCC) patients and HBsAg asymptomatic carriers among individuals infected with hepatitis B virus (HBV) with basal core promoter (BCP) double mutations (A1762T, G1764A). Methods: iTRAQ and liquid chromatography-tandem mass spectrometry were used to identify differentially expressed protein, and an ELISA test was used for the validation test. Results: The total number of proteins identified was 1,125, of which 239 showed statistically significant differences in their expression. The relative concentrations of serum dihydrolipoyl dehydrogenase (DLD), which showed the most significant correlation with liver diseases and infection, were significantly lower in HCC patients than asymptomatic HBsAg carriers and individuals negative for HBsAg. However, only the difference between HCC patients with BCP double mutations and HBsAg-negative individuals could be confirmed by ELISA. Meanwhile, we found that the concentrations of serum DLD in those infected with HBV with BCP double mutations were significantly lower than in individuals with the wild-type BCP. However, the difference in the concentrations of serum DLD between individuals with wild-type BCP and those negative for HBsAg was not significant. Conclusions: HBV with BCP double mutations are associated with lower concentrations of serum DLD
Interaction of perceptual grouping and crossmodal temporal capture in tactile apparent-motion
Previous studies have shown that in tasks requiring participants to report the direction of apparent motion, task-irrelevant mono-beeps can "capture'' visual motion perception when the beeps occur temporally close to the visual stimuli. However, the contributions of the relative timing of multimodal events and the event structure, modulating uni- and/or crossmodal perceptual grouping, remain unclear. To examine this question and extend the investigation to the tactile modality, the current experiments presented tactile two-tap apparent-motion streams, with an SOA of 400 ms between successive, left-/right-hand middle-finger taps, accompanied by task-irrelevant, non-spatial auditory stimuli. The streams were shown for 90 seconds, and participants' task was to continuously report the perceived (left-or rightward) direction of tactile motion. In Experiment 1, each tactile stimulus was paired with an auditory beep, though odd-numbered taps were paired with an asynchronous beep, with audiotactile SOAs ranging from -75 ms to 75 ms. Perceived direction of tactile motion varied systematically with audiotactile SOA, indicative of a temporal-capture effect. In Experiment 2, two audiotactile SOAs-one short (75 ms), one long (325 ms)-were compared. The long-SOA condition preserved the crossmodal event structure (so the temporal-capture dynamics should have been similar to that in Experiment 1), but both beeps now occurred temporally close to the taps on one side (even-numbered taps). The two SOAs were found to produce opposite modulations of apparent motion, indicative of an influence of crossmodal grouping. In Experiment 3, only odd-numbered, but not even-numbered, taps were paired with auditory beeps. This abolished the temporal-capture effect and, instead, a dominant percept of apparent motion from the audiotactile side to the tactile-only side was observed independently of the SOA variation. These findings suggest that asymmetric crossmodal grouping leads to an attentional modulation of apparent motion, which inhibits crossmodal temporal-capture effects
Unique Carboniferous-Permian tectonic-metallogenic framework of Northern Xinjiang (NW China): Constraints for the tectonics of the southern Paleoasian Domain
The late Paleozoic tectonic-metallogenic framework of North Xinjiang of the southern Paleoasian Domain was characterized by a serious of Carboniferous-Permian events, including: (1) late Carboniferous-Permian Chinese Altay island arc and its metamorphism, granulite in the Chinese Altay, radiolarian chert and high-pressure/ultra-high-pressure metamorphism; (2) late Carboniferous-early Permian adakites, Alaskan-type mafic-ultramafic complexes, and calc-alkaline magmatism, together with porphyry copper deposits, which occurred in the North Xinjiang; and (3) late Carboniferous ophiolite and island arc volcanic rocks located in the Tian Shan. Combined with the facts that there was no typical foreland basin, no typical collisional-type granitoid, and there were large amount of strike-slip faulting, it is suggested that in the Carboniferous-early Permian North Xinjiang was characterized by the coexistence of compression-extension-strike-slip structures with active magmatism and metallogeny. These phenomena all indicate that there were active margins during the late Carboniferous-early Permian, leading to the notion that the complicated accretionary orogeny along the southern Paleoasian Domain may have lasted to the latest Carboniferous-Permian.新疆北部晚古生代独特的构造一成矿作用以发育大量石炭纪一二叠纪构造一成矿事件为特征, 其中包括: (l) 发育于晚石炭世一二叠世的阿尔泰岛弧及其变质事件、阿尔泰麻粒岩与基性杂岩、西南天山放射虫硅质岩和高压一超高压一低压麻拉岩相变质事件; (2 )北疆发育的石炭纪(一二叠世)埃达克岩一高镁安山岩一富N d 玄武质岩组合、阿拉斯加型基性一超基性杂岩和大量的与俯冲相关的钙碱性岩浆活动与斑岩型铜矿床成矿作用; (3) 天山晚石炭世晚期蛇绿岩与岛弧火山岩等。结合北疆地区相关的前陆盆地发育不明显、碰撞型花岗岩欠发育与大量发育平行造山带大型走滑构造等现象, 可以认为新疆北部在石炭纪一二叠纪挤压一伸展一走滑并存, 岩浆活动与成矿作用活跃。这些新进展表明新疆北部在晚石炭世一二叠纪可能仍存在活动陆缘, 因此, 古亚洲洋构造域南部复杂增生造山作用最后延至晚石炭世晚期一二叠纪。published_or_final_versio
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