On the Mitchell similarity measure and its application to pattern recognition

This paper is a response to the similarity measure and pattern recognition problem of Mitchell that was published in Pattern Recognition Letters, 2003. The purpose of this paper is threefold. First, we reviewed and revised her computation for similarity measures. Second, we proved that the similarity values for the one-norm should be larger than that for the two-norm for her pattern recognition problem. Third, we proposed a more scattered similarity measure to help researchers determine patterns. Our findings may shed light on the ongoing debate between Li and Cheng, 2002, Mitchell, 2003.     

Body weight management effect of burdock (Arctium lappa L.) root is associated with the activation of AMP-activated protein kinase in human HepG2 cells

Burdock (Arcticum lappa L.) root is used in folk medicine and also as a vegetable in Asian countries. In the present study, burdock root treatment significantly reduced body weight in rats. To evaluate the bioactive compounds, we successively extracted the burdock root with ethanol (AL-1), and fractionated it with n-hexane (AL-2), ethyl acetate (AL-3), n-butanol (AL-4), and water (AL-5). Among these fractions, AL-2 contained components with the most effective hypolipidemic potential in human hepatoma HepG2 cells. AL-2 decreased the expression of fatty acid synthase (FASN) and inhibited the activity of acetyl-coenzyme A carboxylase (ACC) by stimulating AMP-activated protein kinase (AMPK) through the LKB1 pathway. Three active compounds were identified from the AL-2, namely α-linolenic acid, methyl α-linolenate, and methyl oleate. These results suggest that burdock root is expected to be useful for body weight management.     

Highly efficient electrocatalytic hydrogen production via MoSx/3D-graphene as hybrid electrode

Molybdenum sulfide (MoS_x) has recently emerged as a promising catalyst for the hydrogen evolution reaction (HER) in water splitting that may replace the noble metal, such as platinum, as a cost-effective and high catalytic materials. It has been reported that two-dimensional structured MoS_x exhibit significant amount of exposed S-edge, which can be an active electrocatalytic catalyst for hydrogen production. However, the current reports mainly focusing on the planar electrode, where the catalyst utilization and the number of active sites are limited due to the lower exposed specific surface area (SSA) of supporting electrodes. In this work, we utilize the freeze-drying method to produce a porous three-dimensional (3D) structure assembled by graphene flakes. The as-prepared 3D graphene scaffold shows high surface area, high porosity while low density, which makes it as an ideal conductive electrode for supporting of MoS_x catalysts. Moreover, it was found out that the crystallinity of MoS_x, controlled by thermolysis temperature of thiosalts precursor ((NH₄)₂MoS₄), shows significantly influence the performance of HER. The optimized annealing temperature for the designed hybrid electrodes (MoS_x/3D-graphene) was found to create a lot of active sites, which facilitate the electrocatalytic performance for water splitting (overpotential of 163 mV @10 mA/cm² and a Tafel slope of 41 mV/dec). The study provides a potential material, which could pave the way for future applications of hydrogen energy.     

Photoactive Earth‐Abundant Iron Pyrite Catalysts for Electrocatalytic Nitrogen Reduction Reaction

The generation of ammonia, hydrogen production, and nitrogen purification are considered as energy intensive processes accompanied with large amounts of CO₂ emission. An electrochemical method assisted by photoenergy is widely utilized for the chemical energy conversion. In this work, earth‐abundant iron pyrite (FeS₂) nanocrystals grown on carbon fiber paper (FeS₂/CFP) are found to be an electrochemical and photoactive catalyst for nitrogen reduction reaction under ambient temperature and pressure. The electrochemical results reveal that FeS₂/CFP achieves a high Faradaic efficiency (FE) of ≈14.14% and NH₃ yield rate of ≈0.096 µg min^?1 at ?0.6 V versus RHE electrode in 0.25 m LiClO₄. During the electrochemical catalytic reaction, the crystal structure of FeS₂/CFP remains in the cubic pyrite phase, as analyzed by in situ X‐ray diffraction measurements. With near‐infrared laser irradiation (808 nm), the NH₃ yield rate of the FeS₂/CFP catalyst can be slightly improved to 0.1 µg min^?1 with high FE of 14.57%. Furthermore, density functional theory calculations demonstrate that the N₂ molecule has strong chemical adsorption energy on the iron atom of FeS₂. Overall, iron pyrite‐based materials have proven to be a potential electrocatalyst with photoactive behavior for ammonia production in practical applications.     

Measuring and comparing service quality metrics through social media analytics: a case study

This paper proposes a framework of using social media analytics to help study service quality. A case study was conducted to collect and analyze a data set which included nearly half million tweets related to two of the largest supermarkets in the United States: Walmart and Kmart. The results illustrate how businesses can leverage external open data to complement the traditional survey-based approaches in order to better understand and measure their service quality metrics by studying the online opinions of their customers.     

Selective Leaching Process for Neodymium Recovery from Scrap Nd-Fe-B Magnet

Neodymium-iron-boron (Nd-Fe-B) magnets were most widely applied to permanent magnetic products in the world due to their high magnetic force. The increasing growth of scrap Nd-Fe-B magnets resulted in disposal problems and the reduction of neodymium (Nd) valuable resources. In this study, we developed a simple hydrometallurgical precipitation process with pH adjustment to separate and recover Nd 100 pct recovery from scrap Nd-Fe-B magnets. Several physical and chemical methods such as demagnetization, grinding, screening, and leaching processes were also adopted to investigate the recovery of Nd and other metals from scrap Nd-Fe-B magnets. The leaching process was carried out with four leaching reagents such as NaOH, HCl, HNO₃, and H₂SO₄. Batch studies were also conducted to optimize the leaching operating conditions with respect to leaching time, concentration of leaching reagent, temperature, and solid/liquid ratio for both HCl and H₂SO₄ leaching reagents. Nd was successfully separated and recovered with 75.41 wt pct from optimized H₂SO₄ leaching solution through precipitation. Further, the purity and weight percentage of the obtained Nd product was analyzed using scanning electron microscopy–energy-dispersive spectroscopy (SEM-EDS) analysis. An X-ray diffraction (XRD) study confirmed the obtained product of Nd was in the form of NdOOH and Nd(OH)₃.     

Physical,mechanical and thermal properties of cross laminated timber made with coconut wood

European Journal of Wood and Wood Products - The fundamental material properties of coconut wood cross-laminated timber (CLT) were experimentally evaluated with a focus on the effect of the...     

Dynamic credit reservation for online charging of regular Internet of things traffic

According to the specifications of the Third Generation Partnership Project (3GPP), any online charging system must determine a granted unit (GU) and make reservations for each session before the serving network delivers the service. Allocating insufficient GUs to user equipment may incur excessive quantities of reservation messages; conversely, providing excessive GUs could result in an unbalanced distribution of resources. Therefore, a prudent investigation of a reservation scheme for multiple Internet of things (IoT) devices is urgently needed. In this paper, we focus on IoT devices with regular traffic, which usually generate numerous routine traffic events and few event‐driven traffic events. We combine a fixed‐order quantity model (sometimes called a Q model) and propose a novel solution to this issue. To the best of our knowledge, this is the first research to propose a solution based on such a concept. Compared with typical schemes, the simulation results show that our proposed scheme can maintain the success rate with a smaller‐than‐usual number of messages.     

Functional expression of recombinant sweet-tasting protein brazzein by Escherichia coli and Bacillus licheniformis

Brazzein is an attractive sweetener candidate because of its sugar-like taste, high sweetness, and good stability at high temperature and wide pH range. This study was aimed to express and purify bioactive recombinant brazzein (rBrazzein). The rBrazzein gene was synthesized according to the preferred codons of Bacillus subtilis and successfully expressed in Escherichia coli and Bacillus licheniformis. In E. coli host, lower induction temperature of 30°C increased soluble rBrazzein (Ebrazzein) at high level. In B. licheniformis host, two signal peptides (Sec type and Tat type) were evaluated for the expression of rBarzzein in B. subtilis and B. licheniformis. However, only the Sec-type signal peptide guided the secretion expression of rBrazzein in B. licheniformis. The rBrazzein was expressed steadily and the highest yield reached about 57 mg/L at 36 h by small-scale fermentation. The purification procedure of rBrazzein by B. licheniformis (Bbrazzein) was thus established. Approximately 5 mg/L purified rBrazzein was obtained and the purity was 85%. The conformational state of rBrazzeins was confirmed by circular dichroism. The bioactivities of rBrazzeins were evaluated by sweet taste testing. The Bbrazzein and Ebrazzein were 266 times and 400 times sweeter than sucrose on a weight basis, respectively. The formation of disulfide bonds were both confirmed by LC/MS/MS and MALDI-TOF. The CD analysis indicated that Ebrazzein has a similar secondary structure with natural brazzein, which explained why Ebrazzein had a higher intensity of sweetness. This study demonstrated that B. licheniformis system is useful to produce active recombinant brazzein, and has potential food industry applications.     

Managing context data for diverse operating spaces

Context-aware computing is an exciting paradigm in which applications perceive and react to changing environments in an unattended manner. To enable behavioral adaptation, a context-aware application must dynamically acquire context data from different operating spaces in the real world, such as homes, shops and persons. Motivated by the sheer number and diversity of operating spaces, we propose a scalable context data management system in this paper to facilitate data acquisition from these spaces. In our system, we design a gateway framework for all operating spaces and develop matching algorithms to integrate the local context schemas of operating spaces into a global set of domain schemas upon which SQL-based context queries can be issued from applications. The system organizes the operating space gateways as peers in semantic overlay networks and employs distributed query processing techniques over these overlays. Evaluation results on a prototype implementation demonstrate the effectiveness of our system design.