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This work investigated the effect of microstructure on the susceptibility of 304L (metastable), 310S (stable) austenitic and 410 martensitic stainless steels (SSs) to hydrogen embrittlement (HE). Slow-displacement-rate notched tensile tests were performed at various combinations of temperature (25 and 80 °C) and environment (air and H 2 ) to evaluate the relative HE susceptibility of these alloys. At 25 °C, the untempered 410 SS was the specimen most susceptible to HE among the investigated specimens, whereas the 310S and tempered 410 specimens exhibited low HE susceptibility. The formation of strain-induced α′-martensite in a localized region in front of the notch tip was the main cause for the high HE susceptibility of the 304L SS tested at 25 °C. In general, the HE susceptibility was reduced to various degrees for specimens tested at 80 °C. A significantly lower susceptibility to HE was observed for the 304L specimen at 80 °C due to the suppressed formation of α′-martensite in the highly strained region.

U-bent and notched tensile tests in a 80 °C salt-spray environment were conducted to evaluate the effect of cold rolling at room temperature (CR), warm rolling at 150 °C (WR), and a sensitization at 650 °C/10 h (CRS and WRS) on the hydrogen embrittlement (HE) susceptibility of the 304L stainless steel. The CR specimen exhibited the highest crack growth rate with a greater number of short cracks found in the CRS specimen in U-bent tests. The CR specimen was resistant to HE in notched tensile tests relative to other specimens. Cracking in these specimens was more likely to initiate at the slip bands.

The notched tensile strength (NTS) of 304L stainless steel welds subjected to cold rolling (20% thickness reduction) and sensitisation treatment (600 °C/10 h) was measured in a MgCl 2 (40 wt.%) solution at 80 °C. The NTS loss, which is used for comparing the susceptibility to hydrogen embrittlement (HE), was consistent with the extent of embrittled area on the fracture surface of various welds. The HE susceptibility of the weld decreased after cold working but increased with the additional sensitisation treatment of the cold-rolled welds. Besides, cracks tended to propagate along the skeletal boundaries for all welds tested in the MgCl 2 solution.

The effects of cold-rolling (20% thickness reduction) and sensitization treatment (600 °C/10 h) on the microstructure, tensile properties and susceptibility to stress corrosion cracking of 304 stainless steel in 80 °C MgCl 2 (40 wt.%) solution were investigated. The increase in hydrogen traps, which retarded hydrogen diffusion to the strained region, accounted for the low loss in notched tensile strength (NTS) of such a cold-rolled specimen, as compared to the solution-treated specimen in the corrosive environment. By contrast, the high NTS loss of sensitized specimens in MgCl 2 solution was attributed mainly to the formation of stress-induced martensite near grain boundary regions.

Just-in-time (JIT) systems are designed to produce and deliver goods or services as needed, using minimal inventories. It is a logistics philosophy focused on reducing inefficiencies and unproductive time in the production process and is practiced by many manufacturing companies. However, earlier research and experience suggest that the interrelationship between JIT and other manufacturing system’s components such as product design and business strategies are more complex than it is suggested by the traditional JIT studies. In this paper, an alternative view of JIT is offered by using system dynamics (SD) that concentrates on the total system perspective. An integrated framework of JIT and a Kanban model was built using a SD tool and is used for modelling and simulating. It provides a new paradigm to analyse the logistics policies of a company and understand the customers, competitors, and suppliers interactions that shape the company’s performance over time. In this model, the strategies and action steps were addressed and adopted and the resulted in improvement in inventory control, quality and productivity.

Service industry is recognized as being an important industry in Hong Kong and continues to support manufacturing bases in China and other low cost manufacturing countries. However, there is a lack of research on the modelling and analysis of service industry appropriate to Hong Kong’s environment. In this paper, the workflow of a service support department is illustrated using system dynamics modelling approach. The fundamental purpose of system dynamics (SD) is to analyze the information‐feedback of system behaviour as well as to develop mathematical models of dynamic interrelationships. A computer simulation system is used to explore the interactions making experimental system design possible. A model is proposed to simulate the behaviour of this department and to increase the efficiency. The analysis indicates that in order to decrease the turnover time of providing engineering service, it is necessary to make a strategic change to develop new culture and operation structure. The experience demonstrates that system dynamics is a practical approach to identify the relationship between the different service processes and improve the operation efficiency.

Since manually constructing domain-specific sentiment lexicons is extremely time consuming and it may not even be feasible for domains where linguistic expertise is not available, research on automatic construction of domain-specific sentiment lexicons has become a hot topic in recent years. The main contribution of this paper is the illustration of a novel semi-supervised learning method which exploits both term-to-term and document-to-term relations hidden in a corpus for the construction of domain-specific sentiment lexicons. More specifically, the proposed two-pass pseudo labeling method combines shallow linguistic parsing and corpus-base statistical learning to make domain-specific sentiment extraction scalable with respect to the sheer volume of opinionated documents archived on the Internet these days. Our experiments show that the proposed method can generate high quality domain-specific sentiment lexicons according to users' evaluation.

Despite many incidents about fake online consumer reviews have been reported, very few studies have been conducted to date to examine the trustworthiness of online consumer reviews. One of the reasons is the lack of an effective computational method to separate the untruthful reviews (i.e., spam) from the legitimate ones (i.e., ham) given the fact that prominent spam features are often missing in online reviews. The main contribution of our research work is the development of a novel review spam detection method which is underpinned by an unsupervised inferential language modeling framework. Another contribution of this work is the development of a high-order concept association mining method which provides the essential term association knowledge to bootstrap the performance for untruthful review detection. Our experimental results confirm that the proposed inferential language model equipped with high-order concept association knowledge is effective in untruthful review detection when compared with other baseline methods.

Numerous reports have indicated the severity of fake reviews (i.e., spam) posted to various e-Commerce or opinion sharing Web sites. Nevertheless, very few studies have been conducted to examine the trustworthiness of online consumer reviews because of the lack of an effective computational methodology. Unlike other kinds of Web spam, untruthful reviews could just look like other legitimate reviews (i.e., ham), and so it is difficult to apply any features to distinguish the two classes. One main contribution of our research work is the development of a novel computational methodology to combat online review spam. Our experimental results confirm that the KL divergence and the probabilistic language modeling based computational model is effective for the detection of untruthful reviews. Empowered by the proposed computational methods, our empirical study found that around 2% of the consumer reviews posted to a large e-Commerce site is spam.

This paper illustrates the design and development of a fuzzy-ontology based granular IR system to facilitate domain specific search. Based on the notion of information granulation, a novel computational model is developed to estimate the granularity of documents and rank these documents according to the information seekers' specific granularity requirements. The initial experiments confirm that our granular IR system outperforms a vector space based IR system for domain specific search. Our research work opens the door to the application of granular computing methodology to enhance domain specific search on the Internet.

Existing automated opinion mining methods either employ a static lexicon-based approach or a supervised learning approach. Nevertheless, the former method often fails to identify context-sensitive semantics of the opinion words, and the latter approach requires a large number of human labeled training examples. The main contribution of this paper is the illustration of a novel opinion mining method underpinned by context-sensitive text mining and inferential language modeling to improve the effectiveness of opinion mining. Our initial experiments show that the proposed the inferential opinion mining method outperforms the purely lexicon-based opinion finding method in terms of several benchmark measures. Our research opens the door to the development of more effective opinion mining method to discover business intelligence from the Web knowledge base.

With the explosive growth of the information and services deployed to the Web, there is a pressing need to develop an effective service for personalized services discovery and recommendation. Despite personalized services discovery methods have been studied by researchers before, few attempts have been made to explore ontological user profiling and probabilistic language modeling approach for service contextualization and service ranking. This paper makes a novel contribution in terms of developing an agent and ontology based user profiling mechanism to improve the service discovery processes. In particular, a novel probabilistic language modeling approach is developed to conduct service contextualization and service ranking. Our initial experimental results show that the proposed service personalization approach is promising when compared with a baseline system.

There are many methodologies and theories developed for financial investment analysis. Nevertheless, financial analysts tend to adopt their proprietary models and systems to carry out financial investment analysis in practice. To advance both theories and practices in the financial investment domain, a knowledge management (KM) service is highly desirable to enable analysts, academics, and public investors to share their investment knowledge. This paper illustrates the design and development of a Wiki-based investment knowledge management service which supports moderated sharing of structured and unstructured investment knowledge to facilitate investment decision making for both financial analysts and the general public. Our initial usability study shows that the proposed Wiki-based investment knowledge management service is promising.

The optimal approach to thymectomy remains controversial. This study is designed to prospectively compare the results between bilateral video-assisted thoracoscopic thymectomy (BVTx) and extended transsternal thymectomy (ETTx) in patients with myasthenia gravis (MG) without thymoma. Fifteen patients who had undergone BVTx and 16 patients who had undergone ETTx were compared for age, gender, severity of disease, preoperative duration of disease, operative time, intraoperative blood loss, postoperative complications, hospital stay, duration of chest tube drainage, thymic histopathology, pain perception by visual analog scale (VAS), remission and improvement rate, period of follow-up, and activities of daily living (ADL). Fisher’s exact test, t test and paired t test were used for statistical analysis. BVTx had longer operative time and less intraoperative blood loss than that of the ETTx. Their remission rates and their degree of postoperative ADL improvement were not significantly different. However, the lowering of VAS was significantly greater in the sternotomy group at 3 months. All other parameters were not significantly different. No mortality was noted in the series. We consider BVTx as an effective alternative procedure to the transsternal approach for patients with nonthymomatous MG. As more and more people care about cosmetics, BVTx could become the future trend.

1353 A PHASE IIB STUDY OF THE EFFICACY AND SAFETY OF LB80380 VS ENTECAVIR IN TREATMENT-NAIVE PATIENTS WITH CHRONIC HEPATITIS B C.L. Lai, S.H. Ahn, K.S. Lee, S.H. Um, M. Cho, S.K. Yoon, J.W. Lee, N.W. Park, Y.O. Kwon, J.H. Sohn, J.Y. Lee, H.E. Park, J.A. Kim, K.H. Han, M.F. Yuen. The University of Hong Kong, Queen Mary Hospital, Hong Kong, Hong Kong S.A.R., China; College of Medicine, Yonsei University, College of Medicine, Korea University, Seoul, College of Medicine, Pusan National University, Pusan, College of Medicine, The Catholic University of Korea, Seoul, College of Medicine, Inha University, Incheon, College of Medicine, University of Ulsan, Ulsan, College of Medicine, Kyungpook National University, Daegu, College of Medicine, Hanyang University, LG Life Sciences Ltd, Seoul, Republic of Korea E-mail: hrmelcl@hkucc.hku.hk

A holocellulose fraction was isolated from the inner bark of Psedotsuga menziesii and analyzed. It was composed of acid-insoluble lignin (3·1 acid-soluble lignin (4·1%), l -arabinose (2·6%), d -xylose (6.3%). d -mannose(9·5%), d -galactose (2·3%), and d -glcose (61·1%). The presence of these sugars and their configurations were positively established by the preparation of crystalline derivatives. The holocellulose was fractionated into its component polysaccharides, a xylan, a galactoglucomannan, a glucomannan, and a glucan-rich residue.