Search results for: Nathan Zhang

Authors: Ali Alshumrani, Nathan Clarke, Bogdan Ghite, Stavros Shiaeles

Abstract:

Digital forensics has become an essential tool in the investigation of cyber and computer-assisted crime. Arguably, given the prevalence of technology and the subsequent digital footprints that exist, it could have a significant role across almost all crimes. However, the variety of technology platforms (such as computers, mobiles, Closed-Circuit Television (CCTV), Internet of Things (IoT), databases, drones, cloud computing services), heterogeneity and volume of data, forensic tool capability, and the investigative cost make investigations both technically challenging and prohibitively expensive. Forensic tools also tend to be siloed into specific technologies, e.g., File System Forensic Analysis Tools (FS-FAT) and Network Forensic Analysis Tools (N-FAT), and a good deal of data sources has little to no specialist forensic tools. Increasingly it also becomes essential to compare and correlate evidence across data sources and to do so in an efficient and effective manner enabling an investigator to answer high-level questions of the data in a timely manner without having to trawl through data and perform the correlation manually. This paper proposes a Unified Forensic Analysis Tool (U-FAT), which aims to establish a common language for electronic information and permit multi-source forensic analysis. Core to this approach is the identification and development of forensic analyses that automate complex data correlations, enabling investigators to investigate cases more efficiently. The paper presents a systematic analysis of major crime categories and identifies what forensic analyses could be used. For example, in a child abduction, an investigation team might have evidence from a range of sources including computing devices (mobile phone, PC), CCTV (potentially a large number), ISP records, and mobile network cell tower data, in addition to third party databases such as the National Sex Offender registry and tax records, with the desire to auto-correlate and across sources and visualize in a cognitively effective manner. U-FAT provides a holistic, flexible, and extensible approach to providing digital forensics in technology, application, and data-agnostic manner, providing powerful and automated forensic analysis.

Keywords: digital forensics, evidence correlation, heterogeneous data, forensics tool

Procedia PDF Downloads 159

Authors: Richard Okyere Boadu, Judith Obiri-Yeboah, Kwame Adu Okyere Boadu, Nathan Kumasenu Mensah, Grace Amoh-Agyei

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Routine health information system (RHIS) quality assurance has become an important issue, not only because of its significance in promoting a high standard of patient care but also because of its impact on government budgets for the maintenance of health services. A routine health information system comprises healthcare data collection, compilation, storage, analysis, report generation, and dissemination on a routine basis in various healthcare settings. The data from RHIS give a representation of health status, health services, and health resources. The sources of RHIS data are normally individual health records, records of services delivered, and records of health resources. Using reliable information from routine health information systems is fundamental in the healthcare delivery system. Quality assurance practices are measures that are put in place to ensure the health data that are collected meet required quality standards. Routine health information system quality assurance practices ensure that data that are generated from the system are fit for use. This study considered quality assurance practices in the RHIS processes. Methods: A cross-sectional study was conducted in eight health facilities in Tarkwa Sub-Municipal Health Service in the western region of Ghana. The study involved routine quality assurance practices among the 90 health staff and management selected from facilities in Tarkwa Sub-Municipal who collected or used data routinely from 24th December 2019 to 20th January 2020. Results: Generally, Tarkwa Sub-Municipal health service appears to practice quality assurance during data collection, compilation, storage, analysis and dissemination. The results show some achievement in quality control performance in report dissemination (77.6%), data analysis (68.0%), data compilation (67.4%), report compilation (66.3%), data storage (66.3%) and collection (61.1%). Conclusions: Even though the Tarkwa Sub-Municipal Health Directorate engages in some control measures to ensure data quality, there is a need to strengthen the process to achieve the targeted percentage of performance (90.0%). There was a significant shortfall in quality assurance practices performance, especially during data collection, with respect to the expected performance.

Keywords: quality assurance practices, assessment of routine health information system quality, routine health information system, data quality

Procedia PDF Downloads 42

Authors: Ying Wang, Haiyan Xie, Aoming Zhang

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The degree distance of a graph is a graph invariant that is more sensitive than the Wiener index. In this paper, we calculate the vertex degree distances of one vertex union of the cycle and the star, and the degree distance of one vertex union of the cycle and the star. These results lay a foundation for further study on the extreme value of the vertex degree distances, and the distribution of the vertices with the extreme value in one vertex union of the cycle and the star.

Keywords: degree distance, vertex-degree-distance, one vertex union of a cycle and a star, graph

Procedia PDF Downloads 123

Authors: D. Zhang, H. Y. Du, G. W. Li, J. Zeng, D. W. Zuo, Y. P. You

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For the difficult issues of process selection, case-based reasoning technology is applied to computer aided process planning system for cold form tapping of internal threads on the basis of similarity in the process. A model is established based on the analysis of process planning. Case representation and similarity computing method are given. Confidence degree is used to evaluate the case. Rule-based reuse strategy is presented. The scheme is illustrated and verified by practical application. The case shows the design results with the proposed method are effective.

Keywords: case-based reasoning, internal thread, cold extrusion, process planning

Procedia PDF Downloads 479

Authors: Zhan Haiyang, Zhang Lei, Ning Juan

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This paper presents a configuration software solution in Linux, which is used for the control of space environment simulator. After introducing the structure and basic principle, it is said that the developing of QT software frame and the dynamic data exchanging between PLC and computer. The OPC driver in Linux is also developed. This driver realizes many-to-many communication between hardware devices and SCADA software. Moreover, an algorithm named “Scan PRI” is put forward. This algorithm is much more optimizable and efficient compared with "Scan in sequence" in Windows. This software has been used in practical project. It has a good control effect and can achieve the expected goal.

Keywords: Linux OS, configuration software, OPC Server driver, MYSQL database

Procedia PDF Downloads 259

Authors: Huiru Chen, Xuran Zhang

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At present, the residential architecture in China are still causing high energy consumption and high pollution during their whole life cycle, which can be backward compared with the developed countries. The aim of this paper is to discuss the application of green technology to residential architecture in Hangzhou. This article will start with the development of green buildings, then analyzes the use status of green technology in Hangzhou from several specific measures. Analysis of the typical existing green residential buildings in Hangzhou is an attempt to form a preliminary Hangzhou’s green technology application strategy system. Through research, it has been found that the application of green technology in Hangzhou has changed from putting green to the facade, to the combination of the preservation of the traditional green concept and the modern green technology.

Keywords: application, green technology, Hangzhou, residential architecture

Procedia PDF Downloads 176

Authors: Mingmei Zhang, Xinyong Li

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AgInS₂/SnS₂ (AIS) nanocomposites were synthesized by a simple hydrothermal method. The morphology and composition of the fabricated AIS nanocomposites were investigated by field-emission scanning electron microscopy (SEM), X-ray diffraction (XRD), high resolution transmission electron microscopy (HRTEM) and X-ray photoelectron spectroscopy (XPS). Moreover, the as-prepared AIS photocatalysts exhibited excellent photocatalytic activities for the degradation of Norfloxacin (NOR), mainly due to its high optical absorption and separation efficiency of photogenerated electron-hole pairs, as evidenced by UV–vis diffusion reflection spectra (DRS) and Surface photovoltage (SPV) spectra. Furthermore, the interfacial charges transfer mechanism was also discussed by DFT calculations.

Keywords: AIS nanocomposites, electron-hole pairs, charges transfer, DFTcaculations

Procedia PDF Downloads 159

Authors: Yuping Zhang, Teng Ma, Nadia Everaert, Hongfu Zhang

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Supplying dietary fiber during gestation is known to improve the welfare of feed-restricted sows. However, whether high fiber supplementation during pregnancy can improve the performance of sows and their offspring depends on the type, amount, source, etc., in which the solubility plays a key important role. Insoluble fibers have been shown to increase feed intake of sows in lactation, meet the needs of sows for milk production, reduce sow’s weight and backfat loss, and thus improve the performance of sows and their offspring. In this study, we investigated the effect of the addition of fermented feed mulberry (FFM), rich in insoluble fiber, during the whole gestation on the performance of sows and their offspring and explored possible mechanisms by determining serum hormones and fecal microbiota. The FFM-diet contained 25.5% FFM (on dry matter basis) and was compared with the control–diet (CON, corn, and soybean meal diet). The insoluble fiber content of the FFM and CON diet are respectively 29.3% and 19.1%. both groups were allocated 20 multiparous sows, and they are fed different feed allowance to make sure all the sows get the same digestible energy for each day. After farrowing, all sows were fed the same lactation diet ad libitum. The serum estradiol, progesterone concentration, blood glucose, and insulin levels at gestation day 0, 20, and 60 were tested. And also, the composition and differences fecal microbiota at day 60 of gestation were analyzed. Fecal consistency was determined with Bristol stool scale method, those with a score below 3 were counted as constipation The results showed that there was no impact of the FFM treatment on sows’ backfat, bodyweight changes, blood glucose, serum estradiol, and progesterone concentration, litter size, and performance of the offspring(p > 0.05), Except significant decrease in the concentration of insulin in sows’ serum at 60 days of gestation were observed in the FFM group compare to the CON group (P < 0.01). FFM diet also significantly increased feed intake on the first, third, and 21st days of sow lactation. (p < 0.01); The α- and β- diversity and abundance of the microbiota were significant increased (p < 0.01) compared with the CON group, The abundance of Firmicutes and Bacteroidetes were significantly increased, meanwhile the abundances of Spirochetes, Proteobacteria, and Euryarchaeota, were significantly reduced in the feces of the FFM group. We also analyzed the fecal microbiota of constipated sows vs non-constipated sows and found that the diversity and abundance did also differ between these two groups. FFM and CON group < 0.01). The relationship between sow’s constipation and microbiota merits further investigation.

Keywords: fermented feed mulberry, reproductive performance, fecal flora, sow

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Authors: Xiaojie Jiang, Wei Cai, Yinxiao Xiang, Ni Zhang, Mengxin Ren, Xinzheng Zhang, Jingjun Xu

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Reflection phase of graphene plasmons (GPs) at an abrupt interface is very important, which determines the plasmon resonance of graphene structures of deep sub-wavelength scales. However, at an abrupt graphene edge, the reflection phase is always a constant, ΦR ≈ π/4. In this work, we show that the reflection phase of GPs can be efficiently changed through substrate design. Reflection phase of graphene plasmons (GPs) at an abrupt interface is very important, which determines the plasmon resonance of graphene structures of deep sub-wavelength scales. However, at an abrupt graphene edge, the reflection phase is always a constant, ΦR ≈ π/4. In this work, we show that the reflection phase of GPs can be efficiently changed through substrate design. Specifically, the reflection phase is no longer π/4 at the interface formed by placing a graphene sheet on different substrates. Moreover, tailorable reflection phase of GPs up to 2π variation can be further achieved by scattering GPs at a junction consisting of two such dielectric interfaces with various gap width acting as a Fabry-Perot cavity. Besides, the evolution of plasmon mode in graphene ribbons based on the interface reflection phase tuning is predicted, which is expected to be observed in near-field experiments with scattering-type scanning near-field optical microscopy (s-SNOM). Our work provides another way for in-plane plasmon control, which should find applications for integrated plasmon devices design using graphene.Specifically, the reflection phase is no longer π/4 at the interface formed by placing a graphene sheet on different substrates. Moreover, tailorable reflection phase of GPs up to 2π variation can be further achieved by scattering GPs at a junction consisting of two such dielectric interfaces with various gap width acting as a Fabry-Perot cavity. Besides, the evolution of plasmon mode in graphene ribbons based on the interface reflection phase tuning is predicted, which is expected to be observed in near-field experiments with scattering-type scanning near-field optical microscopy (s-SNOM). Our work provides a new way for in-plane plasmon control, which should find applications for integrated plasmon devices design using graphene.

Keywords: graphene plasmons, reflection phase tuning, plasmon mode tuning, Fabry-Perot cavity

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Authors: Mingchuan Zhou, Haitao Zhang, Hongfang Ma, Weiyong Ying

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Alumina supported platinum and tin catalysts with different loadings of Pt and Sn were prepared and characterized by low temperature N₂ adsorption/desorption, H₂-temperature programed reduction and CO pulse chemisorption. Pt and Sn below 1% loading were suitable for acetic acid hydrogenation. The best performance over 0.75Pt1Sn/Al₂O₃ can reach 87.55% conversion of acetic acid and 47.39% selectivity of ethanol. The operating conditions of acetic acid hydrogenation over 1Pt1Sn/Al₂O₃ were investigated. High reaction temperature can enhance the conversion of acetic acid, but it decreased total selectivity of ethanol and acetyl acetate. High pressure and low weight hourly space velocity were beneficial to both conversion of acetic acid and selectivity to ethanol.

Keywords: acetic acid, hydrogenation, operating condition, PtSn

Procedia PDF Downloads 324

Authors: Liping Qiu, Xiaofeng Zhang

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In its long history, precious tomb murals suffered from various diseases due to natural and man-made destruction. The key to how to protect tomb murals is how to strengthen and protect the tomb murals. In order to maximize the life of the tomb murals, the artistic, historic, and scientific values of the tomb murals can be continued. In this paper, four kinds of traditional reinforcement materials (silicone acrylic lotion, pure acrylic lotion, polyvinyl acetate lotion, and B72) are selected to reinforce the ground support layer of tomb murals, and the reinforcement effect of each reinforcement material on the ground support layer of murals is compared and analyzed, and the best protection material is obtained.

Keywords: mural, destruction cycle, reinforcement material, disease

Procedia PDF Downloads 91

Authors: Selina Lin, Justin M Fan, Vincent Zhang, Cindy Chen, Daniel Lam, Jason Yan, Ning Zhang

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Depression is one of the most common mental disorders in the United States, and past studies have shown a concerning increase in the rates of depression in youth populations over time. Furthermore, depression is an especially important issue for Asian Americans because of the anti-Asian violence taking place during the COVID-19 pandemic. While Asian American adolescents are reluctant to seek help for mental health issues, past research has found a prevalence of depressive symptoms in them that have yet to be fully investigated. There have been studies conducted to understand and observe the impacts of multifarious factors influencing the mental well-being of Asian American adolescents; however, they have been generally limited to qualitative investigation, and very few have attempted to quantitatively evaluate the relationship between depression levels and a comprehensive list of factors for those levels at the same time. To better quantify these relationships, this project investigated the prevalence of depression in Asian American teenagers mainly from the Greater Philadelphia Region, aged 12 to 19, and, with an anonymous survey, asked participants 48 multiple-choice questions pertaining to demographic information, daily behaviors, school life, family life, depression levels (quantified by the PHQ-9 assessment), school and family support against depression. Each multiple-choice question was assigned as a factor and variable for statistical and dominance analysis to determine the most influential factors on depression levels of Asian American adolescents. The results were validated via Bootstrap analysis and t-tests. While certain influential factors identified in this survey are consistent with the literature, such as parent-child relationship and peer pressure, several dominant factors were relatively overlooked in the past. These factors include the parents’ relationship with each other, the satisfaction with body image, sex identity, support from the family and support from the school. More than 25% of participants desired more support from their families and schools in handling depression issues. This study implied that it is beneficial for Asian American parents and adolescents to take programs on parents’ relationships with each other, parent-child communication, mental health, and sexual identity. A culturally inclusive school environment and more accessible mental health services would be helpful for Asian American adolescents to combat depression. This survey-based study paved the way for further investigation of effective approaches for helping Asian American adolescents against depression.

Keywords: Asian American adolescents, depression, dominance analysis, t-test, bootstrap analysis

Procedia PDF Downloads 108

Authors: Jing Zhang, Daniel Nikovski

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We propose an approximation algorithm called LINKUMP to compute the Pan Matrix Profile (PMP) under the unnormalized l∞ distance (useful for value-based similarity search) using double-ended queue and linear interpolation. The algorithm has comparable time/space complexities as the state-of-the-art algorithm for typical PMP computation under the normalized l₂ distance (useful for shape-based similarity search). We validate its efficiency and effectiveness through extensive numerical experiments and a real-world anomaly detection application.

Keywords: pan matrix profile, unnormalized euclidean distance, double-ended queue, discord discovery, anomaly detection

Procedia PDF Downloads 214

Authors: Khalifa Al Baloushi, Hongwei Zhang, Terrence Perera

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Over the last few decades, the government of the UAE has been taking actions to consolidate defense manufacturing entities with the view to build a coherent and modern defense manufacturing base. Whilst these actions have significantly improved the overall capabilities of defense manufacturing; further opportunities exist to radically transform the sector. A comprehensive literature review and data collected from a survey identified three potential areas of improvements, (a) integration of Industry 4.0 technologies and other smart technologies, (b) stronger engagement of small and Medium-sized defense manufacturing companies and (c) Enhancing the national defense policies by embedding best practices from other nations. This research paper presents the design and development of a conceptual framework for the UAE defense industrial ecosystem.

Keywords: industry 4.0, defense manufacturing, eco-systems, integration

Procedia PDF Downloads 170

Authors: Xuzhen Yang, Yan Shan, Yabo Ding, Keke DIao, Yanjun Zhang, Yijia Huang

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Purpose: Our aim is to understand the unique experiences of patients with peritoneal dialysis and how they deal with issues brought on by disease and dialysis. Patients and Methods: Semi-structured interview was designed to collect information, and inpatients with peritoneal dialysis in a university-based tertiary hospital in the central province of China were purposively chosen as interviewees. The content analysis method was used to analyze the data. Results: Nine patients participated in the study, and three themes and eight subthemes were generated. Conclusion: Patients using peritoneal dialysis encounter numerous challenges and problems in the process of disease and dialysis, and they took attempt to cope with them well to adapt to living with peritoneal dialysis.

Keywords: peritoneal dialysis, experience, patient, coping strategy

Procedia PDF Downloads 67

Authors: Boris Melnikov, Ye Zhang, Dmitrii Chaikovskii

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This study explores the pseudo-geometric version of the extensively researched Traveling Salesman Problem (TSP), proposing a novel generalization of existing algorithms which are traditionally confined to the geometric version. By adapting the "onion husk" method and introducing auxiliary algorithms, this research fills a notable gap in the existing literature. Through computational experiments using randomly generated data, several metrics were analyzed to validate the proposed approach's efficacy. Preliminary results align with expected outcomes, indicating a promising advancement in TSP solutions.

Keywords: optimization problems, traveling salesman problem, heuristic algorithms, “onion husk” algorithm, pseudo-geometric version

Procedia PDF Downloads 170

Authors: Hamed Hedayatnia, Nathan Van Den Bossche

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Understanding the ways in which climate change accelerates or slows down the process of material deterioration is the first step towards assessing adaptive approaches for the conservation of historical heritage. Analysis of the climate change effects on the degradation risk assessment parameters like freeze-thaw cycles and wind erosion is also a key parameter when considering mitigating actions. Due to the vulnerability of cultural heritage to climate change, the impact of this phenomenon on material degradation criteria with the focus on brick masonry walls in Timurid heritage, located in Iran, was studied. The Timurids were the final great dynasty to emerge from the Central Asian steppe. Through their patronage, the eastern Islamic world in northwestern of Iran, especially in Mashhad and Herat, became a prominent cultural center. Goharshad Mosque is a mosque in Mashhad of the Razavi Khorasan Province, Iran. It was built by order of Empress Goharshad, the wife of Shah Rukh of the Timurid dynasty in 1418 CE. Choosing an appropriate regional climate model was the first step. The outputs of two different climate model: the 'ALARO-0' and 'REMO,' were analyzed to find out which model is more adopted to the area. For validating the quality of the models, a comparison between model data and observations was done in 4 different climate zones in Iran for a period of 30 years. The impacts of the projected climate change were evaluated until 2100. To determine the material specification of Timurid bricks, standard brick samples from a Timurid mosque were studied. Determination of water absorption coefficient, defining the diffusion properties and determination of real density, and total porosity tests were performed to characterize the specifications of brick masonry walls, which is needed for running HAM-simulations. Results from the analysis showed that the threatening factors in each climate zone are almost different, but the most effective factor around Iran is the extreme temperature increase and erosion. In the north-western region of Iran, one of the key factors is wind erosion. In the north, rainfall erosion and mold growth risk are the key factors. In the north-eastern part, in which our case study is located, the important parameter is wind erosion.

Keywords: brick, climate change, degradation criteria, heritage, Timurid period

Procedia PDF Downloads 99

Authors: Zhang Lei, Zhan Haiyang, Gu Miao

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A universal software platform is developed for improving the defects in the practical one. This software platform has distinct advantages in modularization, information management, and the interfaces. Several technologies such as computer technology, virtualization technology, network technology, etc. are combined together in this software platform, and four working modes are introduced in this article including single mode, distributed mode, cloud mode, and the centralized mode. The application area of the software platform is extended through the switch between these working modes. The software platform can arrange the thermal vacuum test process automatically. This function can improve the reliability of thermal vacuum test.

Keywords: software platform, thermal vacuum test, control and measurement, work mode

Procedia PDF Downloads 379

Authors: Shengyong Zhang, Mike Mikulich

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Vibration is a crucial limiting consideration in the analysis and design of airplane wing structures to avoid disastrous failures due to the propagation of existing cracks in the material. In this paper, we build CAD models of aircraft wings to capture the design intent with configurations. Subsequent FEA vibration analysis is performed to study the natural vibration properties and impulsive responses of the resulting user-defined wing models. This study reveals the variations of the wing’s vibration characteristics with respect to changes in its structural configurations. Integrating CAD modelling and FEA vibration analysis enables designers to improve wing architectures for implementing design requirements in the preliminary design stage.

Keywords: aircraft wing, CAD modelling, FEA, vibration analysis

Procedia PDF Downloads 131

Authors: Nafees Ahmed, Nur Izyani Kamaruzman, Saralla Nathan, Mohd Ezharul Hoque Chowdhury, Anuar Zaini Md Zain, Iekhsan Othman, Sharifah Binti Syed Hassan

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Meat quality is always subject to consumer scrutiny when purchasing from retail markets on mislabeling as fresh meat. Various physiological and biochemical changes influence the quality of meat. As a major component of muscle tissue, proteins play a major role in muscle foods. In meat industry, freezing is the most common form of storage of meat products. Repeated cycles of freezing and thawing are common in restaurants, kitchen, and retail outlets and can also occur during transportation or storage. Temperature fluctuation is responsible for physical, chemical, and biochemical changes. Repeated cycles of ‘freeze-thaw’ degrade the quality of meat by stimulating the lipid oxidation and surface discoloration. The shelf life of meat is usually determined by its appearance, texture, color, flavor, microbial activity, and nutritive value and is influenced by frozen storage and subsequent thawing. The main deterioration of frozen meat during storage is due to protein. Due to the large price differences between fresh and frozen–thawed meat, it is of great interest to consumer to know whether a meat product is truly fresh or not. Researchers have mainly focused on the reduction of moisture loss due to freezing and thawing cycles of meat. The water holding capacity (WHC) of muscle proteins and reduced water content are key quality parameters of meat that ultimately changes color and texture. However, there has been limited progress towards understanding the actual mechanisms behind the meat quality changes under the freeze–thaw cycles. Furthermore, effect of freeze-thaw process on integrity of proteins is ignored. In this paper, we have studied the effect of ‘freeze-thawing’ on physicochemical changes of chicken meat protein. We have assessed the quality of meat by pH, spectroscopic measurements, Western Blot. Our results showed that increase in freeze-thaw cycles causes changes in pH. Measurements of absorbance (UV-visible and IR) indicated the degradation of proteins. The expression of various proteins (CREB, AKT, MAPK, GAPDH, and phosphorylated forms) were performed using Western Blot. These results indicated the repeated cycles of freeze-thaw is responsible for deterioration of protein, thus causing decrease in nutritious value of meat. It damges the use of these products in Islamic Sharia.

Keywords: chicken meat, freeze-thaw, halal, protein, western blot

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Authors: M. Honarpardaz, Z. Zhang, J. Derkx, A. Trangärd, J. Larsson

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Pilot stages are one of the most common positioners and regulators in industry. In this paper, we present two novel concepts for pilot stages with low power consumption to regulate a pneumatic device. Pilot 1, first concept, is designed based on a conventional frame core electro-magnetic actuator and a leaf spring to control the air flow and pilot 2 has an axisymmetric actuator and spring made of non-oriented electrical steel. Concepts are simulated in a system modeling tool to study their dynamic behavior. Both concepts are prototyped and tested. Experimental results are comprehensively analyzed and compared. The most promising concept that consumes less than 8 mW is highlighted and presented.

Keywords: electro-magnetic actuator, multidisciplinary system, low power consumption, pilot stage

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Authors: Fanqiang Kong, Jindong Zhang, Daiyin Zhu

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Space-time adaptive processing (STAP) techniques have been motivated as a key enabling technology for advanced airborne radar applications. In this paper, the notion of cognitive radar is extended to STAP technique, and cognitive STAP is discussed. The principle for improving signal-to-clutter ratio (SCNR) based on slow-time coding is given, and the corresponding optimization algorithm based on cyclic and power-like algorithms is presented. Numerical examples show the effectiveness of the proposed method.

Keywords: space-time adaptive processing (STAP), airborne radar, signal-to-clutter ratio, slow-time coding

Procedia PDF Downloads 243

Authors: Jianwen Li, Hongfang Ma, Weixin Qian, Haitao Zhang, Weiyong Ying

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Methanol-to-propylene conversion was carried out in a continuous-flow fixed-bed reactor over nano-sized HZSM-5 zeolites. The HZSM-5 catalysts were synthesized with different Si/Al ratio and silicon sources, and treated with NaOH. The structural property, morphology, and acidity of catalysts were measured by XRD, N₂ adsorption, FE-SEM, TEM, and NH₃-TPD. The results indicate that the increment of Si/Al ratio decreased the acidity of catalysts and then improved propylene selectivity, while silicon sources had slight impact on the acidity but affected the product distribution. The desilication after alkali treatment could increase intracrystalline mesopores and enhance propylene selectivity.

Keywords: alkali treatment, HZSM-5, methanol-to-propylene, synthesis condition

Procedia PDF Downloads 187

Authors: Jianwen Li, Hongfang Ma, Haitao Zhang, Qiwen Sun, Weiyong Ying

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HZSM-5 zeolites modified by iron and phosphorus were applied in catalytic cracking of butene. N2 adsorption and NH3-TPD were employed to measure the structure and acidity of catalysts. The results indicate that increasing phosphorus loading decreased surface area, pore volume and strong acidity of catalysts. The introduction of phosphorus significantly decreased butene conversion and promoted propylene selectivity. The catalytic performance of catalyst was strongly dependent on the reaction conditions. Appropriate reaction conditions could suppress side reactions and enhance propylene selectivity.

Keywords: butene catalytic cracking, HZSM-5, modification, reaction conditions

Procedia PDF Downloads 431

Authors: Chi Zhang, Jun Jiang

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Constitutive equations are very important in finite element (FE) modeling, and the accuracy of the material constants in the equations have significant effects on the accuracy of the FE models. A wide range of constitutive equations are available; however, fitting the material constants in the constitutive equations could be complex and time-consuming due to the strong non-linearity and relationship between the constants. This work will focus on the development of a set of unified MATLAB programs for fitting the material constants in the constitutive equations efficiently. Users will only need to supply experimental data in the required format and run the program without modifying functions or precisely guessing the initial values, or finding the parameters in previous works and will be able to fit the material constants efficiently.

Keywords: constitutive equations, FE modelling, MATLAB program, non-linear curve fitting

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Authors: Runlang Zhu, Weijun Gao, Yinqi Zhang, Gangwei Cai

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In order to deal with issues such as the environmental problems and aging of the population, the Japanese government wanted to achieve goals like 'a city where everyone wants to live' and 'a city full of energy for everyone' by creating environmental, social, and economic values in the process of urban development. They began to promote the concept of 'Environmental Future City' in 2010, aiming to create cities and regions with excellent environments, sustainable economic development, and social systems. After taking a look at the history, concept, and development of environmental future cities, the paper will discuss the evaluation system of them, introduce representative cases, and point out what other cities can learn from their development process.

Keywords: environmental future city, city concept, CASBEE, environmental performance assessment

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Authors: Yanshuang Zhang, Byungho Jeong

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There exists some time lag between the consumption of inputs and the production of outputs. This time lag effect should be considered in calculating efficiency of decision making units (DMU). Recently, a couple of DEA models were developed for considering time lag effect in efficiency evaluation of research activities. However, these models can’t discriminate efficient DMUs because of the nature of basic DEA model in which efficiency scores are limited to ‘1’. This problem can be resolved a super-efficiency model. However, a super efficiency model sometimes causes infeasibility problem. This paper suggests an output oriented super-efficiency model for efficiency evaluation under the consideration of time lag effect. A case example using a long term research project is given to compare the suggested model with the MpO model

Keywords: DEA, Super-efficiency, Time Lag, research activities

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Authors: Fangying Wang, Zhang Sanming, Ni Qian

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In recent years, more and more personalized sound absorbing materials have entered the Chinese room acoustical decoration market. The acoustic performance of three kinds of personalized sound-absorbing materials: Flame-retardant Flax Fiber Sound-absorbing Cotton, Eco-Friendly Sand Acoustic Panel and Transparent Micro-perforated Panel (Film) are tested by Reverberation Room Method. The sound absorption characteristic curves show that their performance match for or even exceed the traditional sound absorbing material. Through the application in the actual projects, these personalized sound-absorbing materials also proved their sound absorption ability and unique decorative effect.

Keywords: acoustic performance, application prospect personalized sound-absorbing materials

Procedia PDF Downloads 155

Authors: Siwar Fadhel, Imen Bahri, Man Zhang

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The switched reluctance machine (SRM) has undeniable qualities in terms of low cost and mechanical robustness. However, its highly nonlinear character and its uncertain parameters justify the development of complicated controls. In this paper, authors present the design of a robust H-infinity current controller for an 8/6 SRM with taking into account the nonlinearity of the SRM and with rejection of disturbances. The electromagnetic torque is indirectly regulated through the current controller. To show the performances of this control, a robustness analysis is performed by comparing the H-infinity and PI controller simulation results. This comparison demonstrates better performances for the presented controller. The effectiveness and robustness of the presented controller are also demonstrated by experimental tests.

Keywords: current regulation, experimentation, robust H-infinity control, switched reluctance machine

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Authors: Lin Tang, Xiaoxia Guo, Lingling Zhang

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Recent vaccine scandals overshadowed China’s accomplishment of public health, triggering discussions on the causes of vaccine incidents. Through legal interpretation of selected vaccine incidents and analysis of systemic vulnerabilities in vaccine circulation and lot release, a panoramic review of legislative progresses in the vaccine administration sheds the light on this debate. In essence, it is the combination of the lagging legal system and the absence of information technology infrastructure in the process of vaccine administration reform that has led to the recurrence of vaccine incidents. These findings have significant implications for further improvement of vaccine administration and China’s participation in global healthcare.

Keywords: legislation, lot release, public health, reform, vaccine administration, vaccine circulation

Procedia PDF Downloads 122