Search results for: Ying Zhao

Authors: Gao Youtao, Zhao Tanran, Jin Bingyu, Xu Bo

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Global navigation satellite system(GNSS) can deliver navigation information for spacecraft orbiting on low-Earth orbits and medium Earth orbits. However, the GNSS cannot navigate the spacecraft on high-Earth orbit or deep space probes effectively. With the deep space exploration becoming a hot spot of aerospace, the demand for a deep space satellite navigation system is becoming increasingly prominent. Many researchers discussed the feasibility and performance of a satellite navigation system on periodic orbits around the Earth-Moon libration points which can be called Lagrangian point satellite navigation system. Autonomous orbit determination (AOD) is an important performance for the Lagrangian point satellite navigation system. With this ability, the Lagrangian point satellite navigation system can reduce the dependency on ground stations. AOD also can greatly reduce total system cost and assure mission continuity. As the elliptical restricted three-body problem can describe the Earth-Moon system more accurately than the circular restricted three-body problem, we study the autonomous orbit determination of Lagrangian navigation constellation using only crosslink range based on elliptical restricted three body problem. Extended Kalman filter is used in the autonomous orbit determination. In order to compare the autonomous orbit determination results based on elliptical restricted three-body problem to the results of autonomous orbit determination based on circular restricted three-body problem, we give the autonomous orbit determination position errors of a navigation constellation include four satellites based on the circular restricted three-body problem. The simulation result shows that the Lagrangian navigation constellation can achieve long-term precise autonomous orbit determination using only crosslink range. In addition, the type of the libration point orbit will influence the autonomous orbit determination accuracy.

Keywords: extended Kalman filter, autonomous orbit determination, quasi-periodic orbit, navigation constellation

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Authors: Yujie Zhao, Jiantao Weng

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In the past decade, with the rapid development of China's economy, the purchasing power and physical demand of residents have been improved, which results in the vast emergence of public buildings like large shopping malls. However, the architects usually focus on the internal functions and streamlines of these buildings, ignoring the impact of the environment on the subjective feelings of building users. Only in Zhejiang province, the infiltration of cold air in winter frequently occurs at the entrance of sizeable commercial complex buildings that have been in operation, which will affect the environmental comfort of the building lobby and internal public spaces. At present, to reduce these adverse effects, it is usually adopted to add active equipment, such as setting air curtains to block air exchange or adding heating air conditioners. From the perspective of energy consumption, the infiltration of cold air into the entrance will increase the heat consumption of indoor heating equipment, which will indirectly cause considerable economic losses during the whole winter heating stage. Therefore, it is of considerable significance to explore the suitable entrance forms for improving the environmental comfort of commercial buildings and saving energy. In this paper, a commercial complex with apparent cold air infiltration problem in Hangzhou is selected as the research object to establish a model. The environmental parameters of the building entrance, including temperature, wind speed, and infiltration air volume, are obtained by Computational Fluid Dynamics (CFD) simulation, from which the heat consumption caused by the natural air infiltration in the winter and its potential economic loss is estimated as the objective metric. This study finally obtains the optimization direction of the building entrance form of the commercial complex by comparing the simulation results of other local commercial complex projects with different entrance forms. The conclusions will guide the entrance design of the same type of commercial complex in this area.

Keywords: air infiltration, commercial complex, heat consumption, CFD simulation

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Authors: Anh Vo Van Ha, Yun Zhao, Luat Cong Nguyen, Tan Khac Chu, Phung Hoang Nguyen, Minh Ngoc Pham, Colin W. Binns, Andy H. Lee

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This study aims to study longitudinal changes in blood pressure (BP) during the 1-year postpartum period and to evaluate the influence of parity, maternal age at delivery, prepregnancy BMI, gestational weight gain, gestational age at delivery and postpartum maternal weight. A prospective longitudinal cohort study of 883 singleton Vietnamese women was conducted in Hanoi, Haiphong, and Ho Chi Minh City, Vietnam during 2015-2017. Women diagnosed with gestational diabetes mellitus at 24-28 weeks of gestation, pre-eclampsia, and hypoglycemia was excluded from analysis. BP was repeatedly measured at discharge, 6 and 12 months postpartum using automatic blood pressure monitors. Linear mixed model with repeated measures was used to describe changes occurring during pregnancy to 1-year postpartum. Parity, self-reported prepregnancy BMI, gestational weight gain, maternal age and gestational age at delivery will be treated as time-invariant variables and measured maternal weight will be treated as a time-varying variable in models. Women with higher measured postpartum weight had higher mean systolic blood pressure (SBP), 0.20 mmHg, 95% CI [0.12, 0.28]. Similarly, women with higher measured postpartum weight had higher mean diastolic blood pressure (DBP), 0.15 mmHg, 95% CI [0.08, 0.23]. These differences were both statistically significant, P < 0.001. There were no differences in SBP and DBP depending on parity, maternal age at delivery, prepregnancy BMI, gestational weight gain and gestational age at delivery. Compared with discharge measurement, SBP was significantly higher in 6 months postpartum, 6.91 mmHg, 95% CI [6.22, 7.59], and 12 months postpartum, 6.39 mmHg, 95% CI [5.64, 7.15]. Similarly, DBP was also significantly higher in 6 and months postpartum than at discharge, 10.46 mmHg 95% CI [9.75, 11.17], and 11.33 mmHg 95% CI [10.54, 12.12]. In conclusion, BP measured repeatedly during the postpartum period (6 and 12 months postpartum) showed a statistically significant increase, compared with after discharge from the hospital. Maternal weight was a significant predictor of postpartum blood pressure over the 1-year postpartum period.

Keywords: blood pressure, maternal weight, postpartum, Vietnam

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Authors: Xin Wu, Yongfeng Zhao, Qingxiang Meng

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In China, quite low proportion of crop residues were used as feedstuff because of its poor palatability and low digestibility. Steam explosion is a physical and chemical feed processing technology which has great potential to improve sapidity and digestibility of crop residues. To investigate the effect of the steam explosion on chemical compositions and efficient energy values, crop residues (rice straw, wheat straw and maize stover) were processed by steam explosion (steam temperature 120-230°C, steam pressure 2-26kg/cm², 40min). Steam-exploded crop residues were regarded as treatment groups and untreated ones as control groups, nutritive compositions were analyzed and effective energy values were calculated by prediction model in INRA (1988, 2010) for both groups. Results indicated that the interaction between treatment and variety has a significant effect on chemical compositions of crop residues. Steam explosion treatment of crop residues decreased neutral detergent fiber (NDF) significantly (P < 0.01), and compared with untreated material, NDF content of rice straw, wheat straw, and maize stover lowered 21.46%, 32.11%, 28.34% respectively. Acid detergent lignin (ADL) of crop residues increased significantly after the steam explosion (P < 0.05). The content of crude protein (CP), ether extract (EE) and Ash increased significantly after steam explosion (P < 0.05). Moreover, predicted effective energy values of each steam-exploded residue were higher than that of untreated ones. The digestible energy (DE), metabolizable energy (ME), net energy for maintenance (NEm) and net energy for gain (NEg)of steam-exploded rice straw were 3.06, 2.48, 1.48and 0.29 MJ/kg respectively and increased 46.21%, 46.25%, 49.56% and 110.92% compared with untreated ones(P < 0.05). Correspondingly, the energy values of steam-exploded wheat straw were 2.18, 1.76, 1.03 and 0.15 MJ/kg, which were 261.78%, 261.29%, 274.59% and 1014.69% greater than that of wheat straw (P < 0.05). The above predicted energy values of steam exploded maize stover were 5.28, 4.30, 2.67 and 0.82 MJ/kg and raised 109.58%, 107.71%, 122.57% and 332.64% compared with the raw material(P < 0.05). In conclusion, steam explosion treatment could significantly decrease NDF content, increase ADL, CP, EE, Ash content and effective energy values of crop residues. The effect of steam explosion was much more obvious for wheat straw than the other two kinds of residues under the same condition.

Keywords: chemical compositions, crop residues, efficient energy values, steam explosion

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Authors: Asif Arshid, Ying Huang, Denver Tolliver

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Finite Element (FE) method coupled with ever-increasing computational powers has substantially advanced the reliability of deterministic three dimensional structural analyses of a structure with uniform material properties. However, railways trackbed is made up of diverse group of materials including steel, wood, rock and soil, while each material has its own varying levels of heterogeneity and imperfections. It is observed that the application of probabilistic methods for trackbed structural analysis while incorporating the material and geometric variabilities is deeply underworked. The authors developed and validated a 3-dimensional FE based numerical trackbed model and in this study, they investigated the influence of variability in Young modulus and thicknesses of granular layers (Ballast and Subgrade) on the reliability index (-index) of the subgrade layer. The influence of these factors is accounted for by changing their Coefficients of Variance (COV) while keeping their means constant. These variations are formulated using Gaussian Normal distribution. Two failure mechanisms in subgrade namely Progressive Shear Failure and Excessive Plastic Deformation are examined. Preliminary results of risk-based probabilistic analysis for Progressive Shear Failure revealed that the variations in Ballast depth are the most influential factor for vertical stress at the top of subgrade surface. Whereas, in case of Excessive Plastic Deformations in subgrade layer, the variations in its own depth and Young modulus proved to be most important while ballast properties remained almost indifferent. For both these failure moods, it is also observed that the reliability index for subgrade failure increases with the increase in COV of ballast depth and subgrade Young modulus. The findings of this work is of particular significance in studying the combined effect of construction imperfections and variations in ground conditions on the structural performance of railroad trackbed and evaluating the associated risk involved. In addition, it also provides an additional tool to supplement the deterministic analysis procedures and decision making for railroad maintenance.

Keywords: finite element analysis, numerical modeling, probabilistic methods, risk and reliability analysis, subgrade

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Authors: Dong Xie, Jun Zhao, Yiming Weng

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One of the challenges in dental cement biomaterials is how to make a restorative with mechanical strengths and wear resistance that are comparable to contemporary dental resin composites. Currently none of the dental cement restoratives has been used in high stress-bearing sites due to their low mechanical strengths and poor wear-resistance. The objective of this study was to synthesize and characterize the poly(alkenoic acid)s with different molecular structures, use these polymers to formulate a dental cement restorative, and study the effect of molecular structures on reaction kinetics, viscosity, and mechanical strengths of the formed polymers and cement restoratives. In this study, poly(alkenoic acid)s with different molecular structures were synthesized. The purified polymers were formulated with commercial Fuji II LC glass fillers to form the experimental cement restoratives. The reaction kinetics was studied via 1HNMR spectroscopy. The formed restoratives were evaluated using compressive strength, diametral tensile strength, flexural strength, hardness and wear-resistance tests. Specimens were conditioned in distilled water at 37 oC for 24 h prior to testing. Fuji II LC restorative was used as control. The results show that the higher the arm number and initiator concentration, the faster the reaction was. It was also found that the higher the arm number and branching that the polymer had, the lower the viscosity of the polymer in water and the lower the mechanical strengths of the formed restorative. The experimental restoratives were 31-53% in compressive strength, 37-55% in compressive modulus, 80-126% in diametral tensile strength, 76-94% in flexural strength, 4-21% in fracture toughness and 53-96% in hardness higher than Fuji II LC. For wear test, the experimental restoratives were only 5.4-13% of abrasive and 6.4-12% of attritional wear depths of Fuji II LC in each wear cycle. The aging study also showed that all the experimental restoratives increased their strength continuously during 30 days, unlike Fuji II LC. It is concluded that polymer molecular structures have significant and positive impact on mechanical properties of dental cement restoratives.

Keywords: dental materials, polymers, strength, biomaterials

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Authors: Dong Tang, Yongli Zhao

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The study of the microstructure of asphalt is of great importance for the analysis of its macroscopic properties. However, the peculiarities of the chemical composition of the asphalt itself and the limitations of existing direct imaging techniques have caused researchers to face many obstacles in studying the microstructure of asphalt. The advantage of small-angle X-ray scattering (SAXS) is that it allows quantitative determination of the internal structure of opaque materials and is suitable for analyzing the microstructure of materials. Therefore, the SAXS technique was used to study the evolution of microstructures on the nanoscale during asphalt aging. And the reasons for the change in scattering contrast during asphalt aging were also explained with the help of Fourier transform infrared spectroscopy (FTIR). SAXS experimental results show that the SAXS curves of asphalt are similar to the scattering curves of scattering objects with two-level structures. The Porod curve for asphalt shows that there is no obvious interface between the micelles and the surrounding mediums, and there is only a fluctuation of the hot electron density between the two. The Beaucage model fit SAXS patterns shows that the scattering coefficient P of the asphaltene clusters as well as the size of the micelles, gradually increase with the aging of the asphalt. Furthermore, aggregation exists between the micelles of asphalt and becomes more pronounced with increasing aging. During asphalt aging, the electron density difference between the micelles and the surrounding mediums gradually increases, leading to an increase in the scattering contrast of the asphalt. Under long-term aging conditions due to the gradual transition from maltenes to asphaltenes, the electron density difference between the micelles and the surrounding mediums decreases, resulting in a decrease in the scattering contrast of asphalt SAXS. Finally, this paper correlates the macroscopic properties of asphalt with microstructural parameters, and the results show that the high-temperature rutting resistance of asphalt is enhanced and the low-temperature cracking resistance decreases due to the aggregation of micelles and the generation of new micelles. These results are useful for understanding the relationship between changes in microstructure and changes in properties during asphalt aging and provide theoretical guidance for the regeneration of aged asphalt.

Keywords: asphalt, Beaucage model, microstructure, SAXS

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Authors: Yaolin Tian, Shanxiong Chen, Fujia Zhao, Xiaoyu Lin, Hailing Xiong

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Ancient books are significant culture inheritors and their background textures convey the potential history information. However, multi-style texture recovery of ancient books has received little attention. Restricted by insufficient ancient textures and complex handling process, the generation of ancient textures confronts with new challenges. For instance, training without sufficient data usually brings about overfitting or mode collapse, so some of the outputs are prone to be fake. Recently, image generation and style transfer based on deep learning are widely applied in computer vision. Breakthroughs within the field make it possible to conduct research upon multi-style texture recovery of ancient books. Under the circumstances, we proposed a network of layout analysis and image fusion system. Firstly, we trained models by using Deep Convolution Generative against Networks (DCGAN) to synthesize multi-style ancient textures; then, we analyzed layouts based on the Position Rearrangement (PR) algorithm that we proposed to adjust the layout structure of foreground content; at last, we realized our goal by fusing rearranged foreground texts and generated background. In experiments, diversified samples such as ancient Yi, Jurchen, Seal were selected as our training sets. Then, the performances of different fine-turning models were gradually improved by adjusting DCGAN model in parameters as well as structures. In order to evaluate the results scientifically, cross entropy loss function and Fréchet Inception Distance (FID) are selected to be our assessment criteria. Eventually, we got model M8 with lowest FID score. Compared with DCGAN model proposed by Radford at el., the FID score of M8 improved by 19.26%, enhancing the quality of the synthetic images profoundly.

Keywords: deep learning, image fusion, image generation, layout analysis

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Authors: Balthazar Temu, Zhao Yan, Bogdan-Petrin Ratiu, Sang Soon Oh, Qiang Li

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Nanowire based Photonic Crystal Surface Emitting Lasers (PCSELs) reported in the literature have been designed using a triangular, square or honeycomb patterns. The triangular and square pattern PCSELs have limited degrees of freedom in tuning the design parameters which hinders the ability to design high quality factor (Q-factor) devices. Nanowire based PCSELs designed using triangular and square patterns have been reported with the lasing thresholds of 130 kW/〖cm〗^2 and 7 kW/〖cm〗^2 respectively. On the other hand the honeycomb pattern gives more degrees of freedom in tuning the design parameters, which can allow one to design high Q-factor devices. A deformed honeycomb pattern device was reported with lasing threshold of 6.25 W/〖cm〗^2 corresponding to a simulated Q-factor of 5.84X〖10〗^5.Despite this achievement, the design principles which can lead to realization of even higher Q-factor honeycomb pattern PCSELs have not yet been investigated. In this work we show that through deforming the honeycomb pattern and tuning the heigh and lattice constants of the nanowires, it is possible to achieve even higher Q-factor devices. Considering three different band edge modes, we investigate how the resonance wavelength changes as the device is deformed, which is useful in designing high Q-factor devices in different wavelength bands. We eventually establish the design and simulation of honeycomb PCSELs operating around the wavelength of 960nm , in the O and the C band with Q-factors up to 7X〖10〗^7. We also investigate the Q-factors of undeformed device, and establish that the mode at the band edge close to 960nm can attain highest Q-factor of all the modes when the device is undeformed and the Q-factor degrades as the device is deformed. This work is a stepping stone towards the fabrication of very high Q-factor, nanowire based honey comb PCSELs, which are expected to have very low lasing threshold.

Keywords: designing nanowire PCSEL, designing PCSEL on silicon substrates, low threshold nanowire laser, simulation of photonic crystal lasers

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Authors: Kevin Wang, Jian Ge, Yinan Zhao, Kevin Willis

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Kepler has discovered over 4000 exoplanets and candidates. However, current transit planet detection techniques based on the wavelet analysis and the Box Least Squares (BLS) algorithm have limited sensitivity in detecting minor planets with a low signal-to-noise ratio (SNR) and long periods with only 3-4 repeated signals over the mission lifetime of 4 years. This paper presents a novel precise-period transit signal detection methodology based on a new Graphics Processing Unit (GPU) Fast Folding algorithm in conjunction with a Convolutional Neural Network (CNN) to detect low SNR and/or long-period transit planet signals. A comparison with BLS is conducted on both simulated light curves and real data, demonstrating that the new method has higher speed, sensitivity, and reliability. For instance, the new system can detect transits with SNR as low as three while the performance of BLS drops off quickly around SNR of 7. Meanwhile, the GPU Fast Folding method folds light curves 25 times faster than BLS, a significant gain that allows exoplanet detection to occur at unprecedented period precision. This new method has been tested with all known transit signals with 100% confirmation. In addition, this new method has been successfully applied to the Kepler of Interest (KOI) data and identified a few new Earth-sized Ultra-short period (USP) exoplanet candidates and habitable planet candidates. The results highlight the promise for GPU Fast Folding as a replacement to the traditional BLS algorithm for finding small and/or long-period habitable and Earth-sized planet candidates in-transit data taken with Kepler and other space transit missions such as TESS(Transiting Exoplanet Survey Satellite) and PLATO(PLAnetary Transits and Oscillations of stars).

Keywords: algorithms, astronomy data analysis, deep learning, exoplanet detection methods, small planets, habitable planets, transit photometry

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Authors: Jiajia Peng, Yijun Dong, Jianjun Ren, Yu Zhao

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Objectives: Understanding the association between sleep traits and tinnitus could help prevent and provide appropriate interventions against tinnitus. Therefore, this study aimed to assess the relationship between different sleep patterns and tinnitus. Design: A cross-sectional analysis using baseline data (2006–2010, n=168,064) by logistic regressions was conducted to evaluate the association between sleep traits (including the overall health sleep score and five sleep behaviors), and the occurrence (yes/no), frequency (constant/transient), and severity (upsetting/not upsetting) of tinnitus. Further, a prospective analysis of participants without tinnitus at baseline (n=9,581) was performed, who had been followed up for seven years (2012–2019) to assess the association between new-onset tinnitus and sleep characteristics. Moreover, a subgroup analysis was also carried out to estimate the differences in sex by dividing the participants into male and female groups. A sensitivity analysis was also conducted by excluding ear-related diseases to avoid their confounding effects on tinnitus (n=102,159). Results: In the cross-sectional analysis, participants with “current tinnitus” (OR: 1.13, 95% CI: 1.04–1.22, p=0.004) had a higher risk of having a poor overall healthy sleep score and unhealthy sleep behaviors such as short sleep durations (OR: 1.09, 95% CI: 1.04–1.14, p<0.001), late chronotypes (OR: 1.09, 95% CI: 1.05–1.13, p<0.001), and sleeplessness (OR: 1.16, 95% CI: 1.11–1.22, p<0.001) than those participants who “did not have current tinnitus.” However, this trend was not obvious between “constant tinnitus” and “transient tinnitus.” When considering the severity of tinnitus, the risk of “upsetting tinnitus” was obviously higher if participants had lower overall healthy sleep scores (OR: 1.31, 95% CI: 1.13–1.53, p<0.001). Additionally, short sleep duration (OR: 1.22, 95% CI: 1.12–1.33, p<0.001), late chronotypes (OR: 1.13, 95% CI: 1.04–1.22, p=0.003), and sleeplessness (OR: 1.43, 95% CI: 1.29–1.59, p<0.001) showed positive correlations with “upsetting tinnitus.” In the prospective analysis, sleeplessness presented a consistently significant association with “upsetting tinnitus” (RR: 2.28, P=0.001). Consistent results were observed in the sex subgroup analysis, where a much more pronounced trend was identified in females compared with males. The results of the sensitivity analysis were consistent with those of the cross-sectional and prospective analyses. Conclusions: Different types of sleep disturbance may be associated with the occurrence and severity of tinnitus; therefore, precise interventions for different types of sleep disturbance, particularly sleeplessness, may help in the prevention and treatment of tinnitus.

Keywords: tinnitus, sleep, sleep behaviors, sleep disturbance

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Authors: Mei Xuan Tan, Eng Ying Bong

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Academic discussion during and after instructional teaching is an integral part of learning. Such discussion between the instructor and student or peer-to-peer discussion can be in several different forms. It could be face-to-face discussion, via email and use of online discussion forum. In this study, the effectiveness of using WhatsApp for academic discussion for a first year half-credit Chemistry course was examined. This study was run over two years with two different batches of students. Participation in the study was voluntary and student volunteers were recruited within the first week of the term. The activity in the WhatsApp group was monitored by two instructors teaching the course. At the end of the course, the students participated in an online survey to evaluate their experience of using WhatsApp for academic discussion. There were a total of 26 questions. The survey had a total of 4 sections with regards to the use of WhatsApp for academic discussion: 1) Familiarity with WhatsApp, 2) Effectiveness of using WhatsApp for discussion, 3) Challenges and 4) Overall experience. The main purpose of using an IM platform for academic discussion was to encourage after-class discussion amongst the students. 32% of the participants had used other online platform, such as Piazza and forums in Learning Management System (LMS), for after-class academic discussion with their instructors and peers. This was a low percentage considering that some courses use such online platform as their main forum amongst instructors and students. At the end of our study, over 83% of the participants felt that WhatsApp was a more effective platform compared to other online forum. One interesting finding was the effect of WhatsApp discussion on face-to-face interaction with instructors. 28% of the students agreed that the use of WhatsApp as a discussion forum had encouraged them to approach their instructors during or after class. 51% of students answered neutral. This could be interpreted that the use of WhatsApp had not affected the frequent (or lack of) face-to-face interaction with their instructors. A second survey question, similar but phrased differently from the first, was also asked to evaluate the aspect of face-to-face interaction with instructors. 34% disagreed that the use of WhatsApp had reduced the frequency of face-to-face interaction. This could imply that the frequency remained the same or might have increased. The 38% who agreed to a decrease in face-to-face interaction have either asked the questions in WhatsApp or had their questions answered by a query from another student in the group chat. These outcomes suggested that the use of technology aided and complemented face-to-face interaction between instructors and students. The study also looked at the challenges of using WhatsApp for academic discussion. Some challenges included difficulty in referring back to previous discussion and students finding some discussions irrelevant to them. In conclusion, the use of IM platform for academic discussion was desirable for the students, but it should not be the only channel as face-to-face consultation and online forum for lengthy discussion are still important for after-class learning of students.

Keywords: chemistry, pedogogy, technological tools, undergraduate

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Authors: Ying Liang, Na Li

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Lipo-alkaloid is a kind of C19-norditerpenoid alkaloids existed in Aconitum species, which usually contains an aconitane skeleton and one or two fatty acid residues. The structures are very similar to that of diester-type alkaloids, which are considered as the main bioactive components in Aconitum carmichaelii. They have anti-inflammatory, anti-nociceptive, and anti-proliferative activities. So far, more than 200 lipo-alkaloids were reported from plants, semisynthesis, and biotransformations. In our research, by the combination of ultra-high performance liquid chromatography-quadruple-time of flight mass spectrometry (UHPLC-Q-TOF-MS) and an in-house database, 148 lipo-alkaloids were identified from A. carmichaelii, including 93 potential new compounds and 38 compounds with oxygenated fatty acid moieties. To our knowledge, this is the first time of the reporting of the oxygenated fatty acids as the side chains in naturally-occurring lipo-alkaloids. Considering the fatty acid residues in lipo-alkaloids should come from the free acids in the plant, the fatty acids and their relationship with lipo-alkaloids were further investigated by GC-MS and LC-MS. Among 17 fatty acids identified by GC-MS, 12 were detected as the side chains of lipo-alkaloids, which accounted for about 1/3 of total lipo-alkaloids, while these fatty acid residues were less than 1/4 of total fatty acid residues. And, total of 37 fatty acids were determined by UHPCL-Q-TOF-MS, including 18 oxidized fatty acids firstly identified from A. carmichaelii. These fatty acids were observed as the side chains of lipo-alkaloids. In addition, although over 140 lipo-alkaloids were identified, six lipo-alkaloids, 8-O-linoleoyl-14-benzoylmesaconine (1), 8-O-linoleoyl-14-benzoylaconine (2), 8-O-palmitoyl-14-benzoylmesaconine (3), 8-O-oleoyl-14-benzoylmesaconine (4), 8-O-pal-benzoylaconine (5), and 8-O-ole-Benzoylaconine (6), were found to be the main components, which accounted for over 90% content of total lipo-alkaloids. Therefore, using these six components as standards, a UHPLC-Triple Quadrupole-MS (UHPLC-QQQ-MS) approach was established to investigate the influence of processing on the contents of lipo-alkaloids. Although it was commonly supposed that the contents of lipo-alkaloids increased after processing, our research showed that no significant change was observed before and after processing. Using the same methods, the lipo-alkaloids in the lateral roots of A. carmichaelii and the roots of A. kusnezoffii were determined and quantified. The contents of lipo-alkaloids in A. kusnezoffii were close to that of the parent roots of A. carmichaelii, while the lateral roots had less lipo-alkaloids than the parent roots. This work was supported by Macao Science and Technology Development Fund (086/2013/A3 and 003/2016/A1).

Keywords: Aconitum carmichaelii, fatty acids, GC-MS, LC-MS, lipo-alkaloids

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Authors: Nigatu Tadesse, Ying Liu, Juan Li, Hong Ming Liu

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Gastric carcinogenesis is a lengthy process of histopathological transition from normal to atrophic gastritis (AG) to intestinal metaplasia (GIM), dysplasia toward gastric cancer (GC). The stage of GIM identified as precancerous lesions with resistance to H-pylori eradication and recurrence after endoscopic surgical resection therapies. GIM divided in to two morphologically distinct phenotypes such as complete GIM bearing intestinal type morphology whereas the incomplete type has colonic type morphology. The incomplete type GIM considered to be the greatest risk factor for the development of GC. Studies indicated the expression of the caudal type homeobox 2 (CDX2) gene is responsible for the development of complete GIM but its progressive downregulation from incomplete metaplasia toward advanced GC identified as the risk for IM progression and neoplastic transformation. The downregulation of CDX2 gene have promoted cell growth and proliferation in gastric and colon cancers and ascribed in chemo-treatment inefficacies. CDX2 downregulated through promoter region hypermethylation in which the methylation frequency positively correlated with the dietary history of the patients, suggesting the role of diet as methyl carbon donor sources such as methionine. However, the metabolism of exogenous methionine is yet unclear. Targeting exogenous methionine metabolism has become a promising approach to limits tumor cell growth, proliferation and progression and increase treatment outcome. This review article discusses molecular alterations that could shed light on the potential of exogenous methionine metabolisms, such as gut microbiota alteration as sources of methionine to host cells, metabolic pathway signaling via PI3K/AKt/mTORC1-c-MYC to rewire exogenous methionine and signature of increased gene methylation index, cell growth and proliferation in GIM, with insights to new treatment avenue via targeting methionine metabolism, and the need for future integrated studies on molecular alterations and metabolomics to uncover altered methionine metabolism and characterization of CDX2 methylation in gastric intestinal metaplasia for potential therapeutic exploitation.

Keywords: altered methionine metabolism, Intestinal metaplesia, CDX2 gene, gastric cancer

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Authors: Chew Zhao Hong

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Since the transition of power in 2018, the Malaysian political landscape has experienced substantial shifts and complexities. The decline of the longstanding ruling party, United Malays National Organization (UMNO), following the party rotation, has given rise to splinter parties such as the Indigenous Unity Party (Bersatu), along with the enduring presence of the Pan-Malaysian Islamic Party (PAS) in the northern region of the Malay Peninsula. However, the "Sheraton Move" in 2020 led to the fall of the Pakatan Harapan government and the emergence of Perikatan Nasional, signifying the ascent of a third political force. The 2022 general elections marked Malaysia's entry into a hung parliament, culminating in an intricate negotiation that resulted in a coalition government formed by Pakatan Harapan, Barisan Nasional, and the Sarawak parties alliance (GPS), collectively governing the Malaysian federal administration. During the 2023 state elections, Pakatan Harapan and Barisan Nasional formed an unprecedented alliance, yet the media framing benefited Perikatan Nasional, even securing substantial support from UMNO's traditional constituencies. In the era of converging new media, Malaysia’s democratization faces new challenges: first, political leaders leveraging media to cultivate unfiltered personas risk inducing populism; second, under the influence of agenda-setting and two-step flow theories, media contributes to polarization; lastly, Malaysia's multi-party system is no longer effectively moderate extreme ideologies into the political center. This study examines the role of media framing and its impact on the democratization process within Malaysia's consociational democracy under a multi-party system and analyzes media discourse before and after the 2023 Malaysian state elections to explore how different parties shape public opinion and political discourse, and how political messages may be amplified or distorted in the process.

Keywords: multi-party system, democratization, elections, political polarization, Malaysia, media framing

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Authors: Chiao-Yi Chen, Dung-Ying Lin

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With the growing awareness of environmental protection and the implementation of government carbon reduction policies, the number of electric vehicles (EVs) has rapidly increased, leading to a surge in charging demand and imposing significant challenges on the existing power grid’s capacity. Traditional urban power grid planning has not adequately accounted for the additional load generated by EV charging, which often strains the infrastructure. This study aims to optimize grid operation and load management by dynamically adjusting EV charging prices based on real-time electricity supply and demand, leveraging consumer demand elasticity to enhance system efficiency. This study uniquely addresses the intricate interplay between urban traffic patterns and power grid dynamics in the context of electric vehicle (EV) adoption. By integrating Hsinchu City's road network with the IEEE 33-bus system, the research creates a comprehensive model that captures both the spatial and temporal aspects of EV charging demand. This approach allows for a nuanced analysis of how traffic flow directly influences the load distribution across the power grid. The strategic placement of charging stations at key nodes within the IEEE 33-bus system, informed by actual road traffic data, enables a realistic simulation of the dynamic relationship between vehicle movement and energy consumption. This integration of transportation and energy systems provides a holistic view of the challenges and opportunities in urban EV infrastructure planning, highlighting the critical need for solutions that can adapt to the ever-changing interplay between traffic patterns and grid capacity. The proposed dynamic pricing strategy effectively reduces peak charging loads, enhances the operational efficiency of charging stations, and maximizes operator profits, all while ensuring grid stability. These findings provide practical insights and a valuable framework for optimizing EV charging infrastructure and policies in future smart cities, contributing to more resilient and sustainable urban energy systems.

Keywords: dynamic pricing, demand elasticity, EV charging, grid load balancing, optimization

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Authors: Xinrui Zhao

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Connective actions acquired a completely different outlook of a social movement which credited with the rapid developed of social media technologies. New social movements amalgamate and mobilize around hashtags, memes, and personalized action frames. In 2017, the #MeToo movements from America spread to a variety of countries as a hashtag on social media. It attempted to demonstrate the widespread prevalence of sexual assault and harassment movement. It also encouraged Chinese women to participate by devoting and contributing their voices and acts. Furthermore, China’s #MeToo movement shows certain characteristics which are strongly shaped by particular political and cultural backgrounds, that also need to be studied. This paper serves as supplementary materials of connective action studies by addressing the #MeToo movement issues in China, which is rarely mentioned previously in the literature, it also supports a view that suggests that ideological and cultural drivers both strategically contribute to personalized action frames. This paper combines textual analysis methods, collecting attached materials from search engines in China’s social media, portrays the structure of China’s #MeToo movements by showing prominent activists, scholars, organization and the public’s action frame in China’s social media(Weibo, wechat, zhihu, douban). In doing so, it seeks to find how China’s #MeToo movements are organized and reveal diversities of social action approaches among those three subjects, digs out the correlations of their actions related to different social media platforms. This analysis suggests that while facing the government's censorship and moral judgments from the public, China’s #MeToo movement combines with few influential sexual assault and harassment events and is lead by the prominent activists who also are the victims in the events. The debates and critiques among Chinese scholars concerned the outcomes and significance of China’s #MeToo movement are divided into sides. Organizations still show less power in participating China’s movement social media. Public’s participation is varied of platforms which hugely affected by their personal experiences and knowledge.

Keywords: connective action, China, MeToo movement, social media

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Authors: Yulin Zhang, Kaixi Dong, Guozhen Zhao

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Background: Different levels of life satisfaction are associated with some individual differences. Understanding the mechanism between them will help to enhance an individual’s well-being. On the one hand, traditional personality such as extraversion has been considered as the most stable and effective factor in predicting life satisfaction to the author’s best knowledge. On the other, individual emotional difference, such as alexithymia (difficulties identifying and describing one’s own feelings), is also closely related to life satisfaction. With the development of positive psychology, positive personalities such as virtues attract wide attention. And according to the broaden-and-build theory, social connectivity may mediate between emotion and life satisfaction. Therefore, the current study aims to explore the mediating role of social connectivity in the effect of positive personality and alexithymia on life satisfaction. Method: This study was conducted with 318 healthy Chinese college students whose age range from 18 to 30. Positive personality (including interpersonal, vitality, and cautiousness) was measured by the Chinese version of Values in Action Inventory of Strengths (VIA-IS). Alexithymia was measured by the Toronto Alexithymia Scale (TAS), and life satisfaction was measured by Satisfaction With Life Scale (SWLS). And social connectivity was measured by six items which have been used in previous studies. Each scale showed high reliability and validity. The mediating model was examined in Mplus 7.2 within a structural equation modeling (SEM) framework. Findings: The model fitted well and results revealed that both positive personality (95% confidence interval of indirect effect was [0.023, 0.097]) and alexithymia (95% confidence interval of indirect effect was [-0.270, -0.089]) predicted life satisfaction level significantly through social connectivity. Also, only positive personality significantly and directly predicted life satisfaction compared to alexithymia (95% confidence interval of direct effect was [0.109, 0.260]). Conclusion: Alexithymia predicts life satisfaction only through social connectivity, which emphasizes the importance of social bonding in enhancing the well-being of Chinese college students with alexithymia. And the positive personality can predict life satisfaction directly or through social connectivity, which provides implications for enhancing the well-being of Chinese college students by cultivating their virtue and positive psychological quality.

Keywords: alexithymia, life satisfaction, positive personality, social connectivity

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Authors: Lingling Li, Peng Zhao, Runze Guan, Alice Jones, Tao Yu

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Background: Shoulder pain and weakness are associated with complex pathologies and often precludes weightlifters from participation in training. The role and mode of exercise training in weightlifters with shoulder pathology remains unclear. Objectives: This case report described an exercise program in management of an elite weightlifter with primary complaint of right shoulder pain and weakness. Methods: A 22-year-old weightlifter presented with 2-year duration of right shoulder pain and weakness which was worsened by routine weightlifting training, and symptoms were not relieved with steroid injection, manual therapy nor usual physiotherapy. There was a limitation in all active range of motion especially horizontal extension (13ᵒ) and external rotation (41ᵒ) with pain intensity at 4/10 and 10/10 (numeric pain rating score) respectively. Muscle weakness was most significant at supraspinatus and teres minor, 38% and 27% respectively compared to his left shoulder (hand-held dynamometry, Micro FET2). An exercise training program focusing on improving mobility was designed for this athlete following a comprehensive physical assessment. Exercises included specific stretching, muscle activating and scapular stability training; once per day, and for 60 minutes each session. All exercises were completed under instruction as pain allowed. Quantitative assessment was conducted at the end of each week for 3 weeks. Outcomes: After the program, the athlete was pain-free in all movements except the O’Brien active compression internal rotation test, the pain was however reduced from 10/10 to 3/10. The horizontal extension and external rotation range increased to 79ᵒ to 120ᵒ respectively, and strength of all rotator cuff muscles returned to normal. At 1-month follow up, the athlete was totally pain-free and had returned to normal function and weightlifting training activities. The outcomes sustained through 6-month and one year. Conclusion: This case report supports the use of a mobility-focused exercise program for management of shoulder pain and weakness in an elite weightlifter athlete.

Keywords: exercise training, mobility, rehabilitation, shoulder pain, weightlifting

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Authors: Haifeng Shi, Kun Song, Yili Zhao

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In China, with the extensive promotion of the ‘aging in place’ pension policy as the background, most of the elders will choose to remain in their current homes and communities, finding out of preference or necessity that they will need to remodel their homes to fit their changing needs. This generation elder born in the 1960s to 1970s almost live in the same form of housing-condominium built from 1982 to 2012. Based on the survey of existing multi-family housing, especially in Tianjin, it is found that the current ‘double two-thirds principles’ is becoming the threshold for modification to existing house, particularly in the project of elevators addition to existing condominium (built from 1982 to 2016 without elevators below 6 floors according to the previous building code). Firstly, this article concludes the local policies of elevator addition nationwide, most of which has determined the importance and necessity of the community-based self-organization principle in the operation of the elevator addition. Secondly, by comparing the three existing community management systems (owners' congress, property management system and community committee) in instances, find that the community-based ‘two-thirds’ principle is not conducive to implement for multi-owned property renovation in the community or common accessibility modification in the building. However, analysis the property and other community management related laws, pointing out the shortcomings of the existing community-based ‘two-thirds’ decision-making norms. The analyzation showed that the unit-based and ‘100% principle’ method is more capable of common accessibility in the condominium in China. Differing from existing laws, the unit-based principle will be effective for the process of decision-making and ‘100% principle’ will protect closely profit-related householders for condominium modification in the multi-owned area. These three aspects of the analysis suggest that the establishment of the unit-based self-organization mechanism is a preferred and inevitable method to solve the problem of elevators addition to the existing condominium in China.

Keywords: aging in place, condominium, modification, multi own

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Authors: Zhao Xinlei

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In general, interstate relations are diverse and include economic, political, military, and diplomatic. Therefore, by analyzing the development of the relationship between Malaysia and China, we can better verify how the Hirschman effect works between small countries and great powers. This paper mainly adopts qualitative research methods and uses Malaysia's 2020-2022 political crisis as a specific case to verify the practice of the Hirschman effect between small and large countries. In particular, the interest groups in small countries that are closely related to trade with extraordinary abilities, as the primary beneficiaries in the development of trade between the two countries, although they may use their resources to a certain extent to influence the decisions of small countries towards great powers, they do not fundamentally determine the small countries' response to large countries. In this process, the relative power asymmetry between states plays a dominant role, as small states lack trust and suspicion in political diplomacy towards large states based on the perception of threat arising from the relative power asymmetry. When developing bilateral relations with large countries, small states seek practical cooperation to promote economic and trade development but become more cautious in their political ties to avoid being caught in power struggles between large states or being controlled by them. The case of Malaysia-China relations also illustrates that despite the ongoing political crisis in Malaysia, which saw the country go through the transition from (Perikatan Nasional) PN to (Barisan Nasional) BN, different governments have maintained a pragmatic and proactive economic policy towards China to reduce suspicion and mistrust between the two countries in political and diplomatic affairs, thereby enhancing cooperation and interactions between the two countries. At the same time, the Malaysian government is developing multi-dimensional foreign relations and actively participating in multilateral, regional organizations and platforms, such as those organized by the United States, to maintain a relative balance in the influence of the US and China on Malaysia.

Keywords: Hirschman effect, interest groups, Malaysia, China, bilateral relations

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Authors: Chiu-Wen Chang, I-Yun Chang, Wei-Ting Chen, Hui-Ping Ho, Chao-Ying Pan, Joh-Jong Huang

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Dengue is a ‘community disease’ or ‘environmental disease’, as long as the environment exist suitable container (including natural and artificial) for mosquito breeding, once the virus invade will lead to the dengue epidemic. Surveillance of vector density is critical to effective infectious disease control and play an important role in monitoring the dynamics of mosquitoes in community, such as mosquito species, density, distribution area. The objective of this study was to examine the relationship in vector density survey (Breteau index, Adult index, House index, Container index, and Larvae index) form 2014 to 2016 in Kaohsiung City and evaluate the effects of introducing the Breeding Elimination and Appraisal Team (hereinafter referred to as BEAT) as an intervention measure on eliminating dengue vector breeding site started from May 2016. BEAT were performed on people who were suspected of contracting dengue fever, a surrounding area measuring 50 meters by 50 meters was demarcated as the emergency prevention and treatment zone. BEAT would perform weekly vector mosquito inspections and vector mosquito inspections in regions with a high Gravitrap index and assign a risk assessment index to each region. These indices as well as the prevention and treatment results were immediately reported to epidemic prevention-related units every week. The results indicated that, vector indices from 2014 to 2016 showed no statistically significant differences in the Breteau index, adult index, and house index (p > 0.05) but statistically significant differences in the container index and larvae index (p <0.05). After executing the integrated elimination work, container index and larvae index are statistically significant different from 2014 to 2016 in the (p < 0.05). A post hoc test indicated that the container index of 2014 (M = 12.793) was significantly higher than that of 2016 (M = 7.631), and that the larvae index of 2015 (M = 34.065) was significantly lower than that of 2014 (M = 66.867). The results revealed that effective vector density surveillance could highlight the focus breeding site and then implement the immediate control action (BEAT), which successfully decreased the vector density and the risk of dengue epidemic.

Keywords: Breteau index, dengue control, monitoring method, vector density

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Authors: Andrew Fox, Tao Zhang, Yuanhong Zhao, Qingping Yang

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The furniture manufacturing industry has been slow in general to adopt the latest manufacturing technologies, historically relying heavily upon specialised conventional machinery. This approach not only requires high levels of specialist process knowledge, training, and capital investment but also suffers from significant subtractive manufacturing waste and high logistics costs due to the requirement for centralised manufacturing, with high levels of furniture product not re-cycled or re-used. This paper aims to address the problems by introducing suitable digital manufacturing technologies to create step changes in furniture manufacturing design, as the traditional design practices have been reported as building in 80% of environmental impact. In this paper, a 3D printing robot for furniture manufacturing is reported. The 3D printing robot mainly comprises a KUKA industrial robot, an Arduino microprocessor, and a self-assembled screw fed extruder. Compared to traditional 3D printer, the 3D printing robot has larger motion range and can be easily upgraded to enlarge the maximum size of the printed object. Generative design is also investigated in this paper, aiming to establish a combined design methodology that allows assessment of goals, constraints, materials, and manufacturing processes simultaneously. ‘Matrixing’ for part amalgamation and product performance optimisation is enabled. The generative design goals of integrated waste reduction increased manufacturing efficiency, optimised product performance, and reduced environmental impact institute a truly lean and innovative future design methodology. In addition, there is massive future potential to leverage Single Minute Exchange of Die (SMED) theory through generative design post-processing of geometry for robot manufacture, resulting in ‘mass customised’ furniture with virtually no setup requirements. These generatively designed products can be manufactured using the robot based additive manufacturing. Essentially, the 3D printing robot is already functional; some initial goals have been achieved and are also presented in this paper.

Keywords: additive manufacturing, generative design, robot, sustainability

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Authors: Melanie Ostermann, Eivind Birkeland, Ying Xue, Alexander Sauter, Mihaela R. Cimpan

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Background: New reliable and robust techniques to assess biological effects of nanomaterials (NMs) in vitro are needed to speed up safety analysis and to identify key physicochemical parameters of NMs, which are responsible for their acute cytotoxicity. The central aim of this study was to validate and evaluate the applicability and reliability of an impedance-based flow cytometry (IFC) technique for the high-throughput screening of NMs. Methods: Eight inorganic NMs from the European Commission Joint Research Centre Repository were used: NM-302 and NM-300k (Ag: 200 nm rods and 16.7 nm spheres, respectively), NM-200 and NM- 203 (SiO₂: 18.3 nm and 24.7 nm amorphous, respectively), NM-100 and NM-101 (TiO₂: 100 nm and 6 nm anatase, respectively), and NM-110 and NM-111 (ZnO: 147 nm and 141 nm, respectively). The aim was to assess the biological effects of these materials on human monoblastoid (U937) cells. Dispersions of NMs were prepared as described in the NANOGENOTOX dispersion protocol and cells were exposed to NMs at relevant concentrations (2, 10, 20, 50, and 100 µg/mL) for 24 hrs. The change in electrical impedance was measured at 0.5, 2, 6, and 12 MHz using the IFC AmphaZ30 (Amphasys AG, Switzerland). A traditional toxicity assay, Trypan Blue Dye Exclusion assay, and dark-field microscopy were used to validate the IFC method. Results: Spherical Ag particles (NM-300K) showed the highest toxic effect on U937 cells followed by ZnO (NM-111 ≥ NM-110) particles. Silica particles were moderate to non-toxic at all used concentrations under these conditions. A higher toxic effect was seen with smaller sized TiO2 particles (NM-101) compared to their larger analogues (NM-100). No interferences between the IFC and the used NMs were seen. Uptake and internalization of NMs were observed after 24 hours exposure, confirming actual NM-cell interactions. Conclusion: Results collected with the IFC demonstrate the applicability of this method for rapid nanotoxicity assessment, which proved to be less prone to nano-related interference issues compared to some traditional toxicity assays. Furthermore, this label-free and novel technique shows good potential for up-scaling in directions of an automated high-throughput screening and for future NM toxicity assessment. This work was supported by the EC FP7 NANoREG (Grant Agreement NMP4-LA-2013-310584), the Research Council of Norway, project NorNANoREG (239199/O70), the EuroNanoMed II 'GEMN' project (246672), and the UH-Nett Vest project.

Keywords: cytotoxicity, high-throughput, impedance, nanomaterials

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Authors: Yin-Hsuan Wu, Perng-Jy Tsai, Ying-Fang Wang, Shun-Hui Chung

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The present study was conducted to characterize exposure concentrations, concentrations deposited on the different respiratory regions, and resultant health risks associated with heavy metal exposures for road marking workers. Road marking workers of three similar exposure groups (SEGs) were selected, including the paint pouring worker, marking worker, and preparing worker. Personal exposure samples were collected using an inhalable dust sampler (IOM), and the involved particle size distribution samples were estimated using an eight-stage Marple personal cascade impactor during five working days. In total, 25 IOM samples and 20 Marple samples were collected. All collected samples were analyzed for their heavy metal contents using the ICP/MS. The resultant heavy metal particle size distributions were also used to estimate the fractions of particle deposited on the head airways (Chead), tracheobronchial (Cthorac) and alveolar regions (Cresp) of the exposed workers. In addition, Pb and Cr were selected to estimate the incremental cancer risk, and Zn, Ti, and Mo were selected to estimate the corresponding non-cancer risk in the present study. Results show that three heavy metals, including Pb, Cr, and Ti, were found with the highest concentrations for the SEG of the paint pouring worker (=0.585±2.98, 0.307±1.71, 0.902±2.99 μg/m³, respectively). For the fraction of heavy metal particle deposited on the respiratory tract, both alveolar and head regions were found with the highest values (=23-43% and 39-61%, respectively). For both SEGs of the paint pouring and marking, 51% of Cr, 59-61% of Zn, and 48-51% of Ti were found to be deposited on the alveolar region, and 41-43% of Pb was deposited on the head region. Finally, the incremental cancer risk for the SEGs of the paint pouring, marking, and preparing were found as 1.08×10⁻⁵, 2.78×10⁻⁶, and 2.20×10⁻⁶, respectively. In addition, the estimated non-cancer risk for the above three SEGs was found to be consistently less than unity. In conclusion, though the estimated non-cancer risk was less than unity, all resultant incremental cancer risk was greater than 10⁻⁶ indicating the abatement of workers’ exposure is necessary. It is suggested that strategies, including placing on the molten kettle, substitution the currently used paints for less heavy metal containing paints, and wearing fume protecting personal protective equipment can be considered in the future from reducing the worker’s exposure aspect.

Keywords: health risk assessment, heavy metal, respiratory track deposition, road marking

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Authors: Sangwoo Han, Saeed Khaleghi Rahimian, Ying Liu

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Vehicle electrification is gaining momentum, and many car manufacturers promise to deliver more electric vehicle (EV) models to consumers in the coming years. In controlling the battery pack, the battery management system (BMS) must maintain optimal battery performance while ensuring the safety of a battery pack. Tasks related to battery performance include determining state-of-charge (SOC), state-of-power (SOP), state-of-health (SOH), cell balancing, and battery charging. Safety related functions include making sure cells operate within specified, static and dynamic voltage window and temperature range, derating power, detecting faulty cells, and warning the user if necessary. The BMS often utilizes an RC circuit model to model a Li-ion cell because of its robustness and low computation cost among other benefits. Because an equivalent circuit model such as the RC model is not a physics-based model, it can never be a prognostic model to predict battery state-of-health and avoid any safety risk even before it occurs. A physics-based Li-ion cell model, on the other hand, is more capable at the expense of computation cost. To avoid the high computation cost associated with a full-order model, many researchers have demonstrated the use of a single particle model (SPM) for BMS applications. One drawback associated with the single particle modeling approach is that it forces to use the average current density in the calculation. The SPM would be appropriate for simulating drive cycles where there is insufficient time to develop a significant current distribution within an electrode. However, under a continuous or high-pulse electrical load, the model may fail to predict cell voltage or Li⁺ plating potential. To overcome this issue, a multi-particle reduced-order model is proposed here. The use of multiple particles combined with either linear or nonlinear charge-transfer reaction kinetics enables to capture current density distribution within an electrode under any type of electrical load. To maintain computational complexity like that of an SPM, governing equations are solved sequentially to minimize iterative solving processes. Furthermore, the model is validated against a full-order model implemented in COMSOL Multiphysics.

Keywords: battery management system, physics-based li-ion cell model, reduced-order model, single-particle and multi-particle model

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Authors: Ying Jia Teoh

Abstract:

The Canning Basin is located between the Kimberley and Pilbara Precambrian cratonic blocks. It is a large but relatively poorly explored Paleozoic basin in remote Western Australia. During the early Ordovician period, the Australian continent was located near the equator. Middle Ordovician age Nita and Goldwyer Formations in Canning Basin are therefore warm water carbonates. The Nita Formation carbonates are a regressive sequence which conformably overlies the Goldwyer Formation. It contains numerous progradational cycles of limestone, vuggy dolomitized carbonate beds and shale deposited in subtidal to supratidal environments. The Goldwyer Formation contains transgressive shale sequences and regressive carbonates deposited in shallow subtidal conditions. The shales contain oil-prone Gloeocapsormorpha prisca-bearing source rocks. Llanvirnian relative sea-level fluctuations were reconstructed by using Fischer plots methodology for three key wells (wells McLarty 1, Looma 1 and Robert 1) in Broome Platform and compared with INPEFA data. The Goldwyer lower shale (interval Or1000P) shows increasing relative sea-level and this matches with a transgressive systems tract. Goldwyer middle carbonate (interval Or2000) shows relative sea-level drop and this matches with a regressive systems tract. Goldwyer upper shale (interval Or2000P) shows relative sea-level drop and this matches with a transgressive systems tract. Nita Formation Leo Member (interval Or3000) shows a relative sea level drop and this matches with a regressive systems tract. The Nita Formation Cudalgarra Member (intervals Or3000P and Or4000) with transgressive systems tract then this is followed by a regressive systems tract. This pattern matches with the relative sea-level curves in wells McLarty 1 and Robert 1. The correlation is weak for parts of well Looma 1. This is probably influenced by the fact that the thickness of this section is quite small. As a conclusion, Fischer plots for the Llanvirnian Goldwyer and Nita Formations show good agreement with the third order global sea level cycles of Haq and others. Fischer plots are generally correlated well with trend and cyclicity determined by INPEFA curves and as a method of cross-checking INPEFA data and sea-level change.

Keywords: canning basin, Fischer plots, Llanvirnian, middle Ordovician, sea-level fluctuations, stratigraphy

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Authors: Youtao Gao, Bingyu Jin, Tanran Zhao, Bo Xu

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The history of satellite navigation can be dated back to the 1960s. From the U.S. Transit system and the Russian Tsikada system to the modern Global Positioning System (GPS) and the Globalnaya Navigatsionnaya Sputnikovaya Sistema (GLONASS), performance of satellite navigation has been greatly improved. Nowadays, the navigation accuracy and coverage of these existing systems have already fully fulfilled the requirement of near-Earth users, but these systems are still beyond the reach of deep space targets. Due to the renewed interest in space exploration, a novel high-precision satellite navigation system is becoming even more important. The increasing demand for such a deep space navigation system has contributed to the emergence of a variety of new constellation architectures, such as the Lunar Global Positioning System. Apart from a Walker constellation which is similar to the one adopted by GPS on Earth, a novel constellation architecture which consists of libration point satellites in the Earth-Moon system is also available to construct the lunar navigation system, which can be called accordingly, the libration point satellite navigation system. The concept of using Earth-Moon libration point satellites for lunar navigation was first proposed by Farquhar and then followed by many other researchers. Moreover, due to the special characteristics of Libration point orbits, an autonomous orbit determination technique, which is called ‘Liaison navigation’, can be adopted by the libration point satellites. Using only scalar satellite-to-satellite tracking data, both the orbits of the user and libration point satellites can be determined autonomously. In this way, the extensive Earth-based tracking measurement can be eliminated, and an autonomous satellite navigation system can be developed for future space exploration missions. The method of state estimate is an unnegligible factor which impacts on the orbit determination accuracy besides type of orbit, initial state accuracy and measurement accuracy. We apply the extended Kalman filter(EKF) and the unscented Kalman filter(UKF) to determinate the orbits of Lagrangian navigation satellites. The autonomous orbit determination errors are compared. The simulation results illustrate that UKF can improve the accuracy and z-axis convergence to some extent.

Keywords: extended Kalman filter, autonomous orbit determination, unscented Kalman filter, navigation constellation

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Authors: Floriane Shala, Evangeline Wagner, Yichun Zhao

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Background: Proper educational training and support are proven to be major components of EHR (Electronic Health Record) implementation and use. However, the majority of health providers are not sufficiently trained in EHR use, leading to adverse events, errors, and decreased quality of care. In response to this, students studying Health Information Science, Public Health, Nursing, and Medicine should all gain a thorough understanding of EHR use at different levels for different purposes. The design of a usable and safe EHR system that accommodates the needs and workflows of different users, user groups, and disciplines is required for EHR learning to be efficient and effective. Objectives: This project builds several artifacts which seek to address both the educational and usability aspects of an educational EHR. The artifacts proposed are models for and examples of such an EHR with a configurable UI to be learned by students who need a background in EHR use during their degrees. Methods: Review literature and gather professional opinions from domain experts on usability, the use of workflow patterns, UI configurability and design, and the educational aspect of EHR use. Conduct interviews in a semi-casual virtual setting with open discussion in order to gain a deeper understanding of the principal aspects of EHR use in educational settings. Select a specific task and user group to illustrate how the proposed solution will function based on the current research. Develop three artifacts based on the available research, professional opinions, and prior knowledge of the topic. The artifacts capture the user task and user’s interactions with the EHR for learning. The first generic model provides a general understanding of the EHR system process. The second model is a specific example of performing the task of MRI ordering with a configurable UI. The third artifact includes UI mock-ups showcasing the models in a practical and visual way. Significance: Due to the lack of educational EHRs, medical professionals do not receive sufficient EHR training. Implementing an educational EHR with a usable and configurable interface to suit the needs of different user groups and disciplines will help facilitate EHR learning and training and ultimately improve the quality of patient care.

Keywords: education, EHR, usability, configurable

Procedia PDF Downloads 157

Authors: Guoqing Wang, Yanhua Zhao, Lina Zhang, Jingbin Bai, Ruican Zhu

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Friction stir welding with bobbin tool is a simple technique compared to conventional FSW since the backing fixture is no longer needed and assembling labor is reduced. It gets adopted more and more in the aerospace industry as a result. However, a post-weld problem, the left keyhole, has to be fixed by forced repair welding. To close the keyhole, the conventional fusion repair could be an option if the joint properties are not deteriorated; friction push plug welding, a forced repair, could be another except that a rigid support unit is demanded at the back of the weldment. Therefore, neither of the above ways is satisfaction in welding a large enclosed structure, like rocket propellant tank. Although friction pulls plug welding does not need a backing plate, the wide applications are still held back because of the disadvantages in respects of unappropriated tensile stress, (i.e. excessive stress causing neck shrinkage of plug that will bring about back defects while insufficient stress causing lack of heat input that will bring about face defects), complicated welding parameters (including rotation speed, transverse speed, friction force, welding pressure and upset)，short welding time (approx. 0.5 sec.), narrow windows and poor stability of process. In this research, an updated technique called inertia friction pull plug welding, and its equipment was developed. The influencing rules of technological parameters on joint properties of inertia friction pull plug welding were observed. The microstructure characteristics were analyzed. Based on the elementary performance data acquired, the conclusion is made that the uniform energy provided by an inertia flywheel will be a guarantee to a stable welding process. Meanwhile, due to the abandon of backing plate, the inertia friction pull plug welding is considered as a promising technique in repairing keyhole of bobbin tool FSW and point type defects of aluminium base material.

Keywords: defect repairing, equipment, inertia friction pull plug welding, technological parameters

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