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Evaluation of Ability of Two Different Pneumatic Boxing Gloves to Reduce Delivered Impact Forces and Improve Safety 被引量:3
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作者 Paul Perkins Alex Jamieson +1 位作者 Wayne Spratford Allan Hahn 《World Journal of Engineering and Technology》 2018年第2期457-491,共35页
Two prototype pneumatic boxing gloves of different design were compared against conventional 10?oz (Std 10?oz) and 16?oz (Std 16?oz) gloves in terms of ability to reduce impact forces delivered to a target. One of the... Two prototype pneumatic boxing gloves of different design were compared against conventional 10?oz (Std 10?oz) and 16?oz (Std 16?oz) gloves in terms of ability to reduce impact forces delivered to a target. One of the pneumatic gloves (SBLI) contained a sealed air bladder inflated to a pressure of 2?kPa. The other (ARLI) incorporated a bladder that allowed release of air to the external environment upon contact with a target, followed by rapid air reuptake. Each glove was placed on to a mechanical fist and dropped 10 times on to an in-floor force plate from each of nine heights ranging from 1.0 to 5.0 metres, with the 5-metre drop generating a peak pre-impact glove velocity close to the reported maximum for elite boxers. Compared to the conventional gloves, the ARLI glove substantially reduced peak impact forces at all drop heights, with the reduction exceeding 30% even at the 5-metre level. The SBLI glove was as effective as the ARLI glove in reducing peak impact forces at drop heights of up to 2.5 metres, but its performance then progressively diminished, and at drop heights of 4.0, 4.5 and 5.0 metres it produced peak force readings similar to those recorded for the Std 10?oz and Std 16?oz gloves. The superiority of the ARLI glove was even more evident in relation to peak rate of force development, with reductions relative to the Std 10?oz glove being ~60% at drop heights up to 3.5 metres and still ~47% at 5 metres. Peak rate of force development for the SBLI glove exceeded that for the ARLI glove for all drop heights of 2.0 metres and above, and at 4.0, 4.5 and 5.0 metres it was higher than the readings for the Std 10 oz and 16?oz gloves. The protective effect of the ARLI glove was?associated with an increase in impact compliance and prolongation of contact time between glove and target. It is concluded that a pneumatic boxing glove that provides for air exchange with the external environment can greatly reduce impact magnitudes across the whole range of pre-impact glove velocities likely to be encountered in boxing, thereby mitigating risks associated with the sport. While acceptance of the gloves by the boxing community is uncertain, opportunity may exist for almost immediate uptake in modified boxing programs. 展开更多
关键词 BOXING BOXING SAFETY Box’Tag Modifed BOXING ModBox PNEUMATIC Box-ing GLOVE SPORT Technology
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A New S-Box Design System for Data Encryption Using Artificial Bee Colony Algorithm
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作者 Yazeed Yasin Ghadi Mohammed SAlshehri +4 位作者 Sultan Almakdi Oumaima Saidani Nazik Alturki Fawad Masood Muhammad Shahbaz Khan 《Computers, Materials & Continua》 SCIE EI 2023年第10期781-797,共17页
Securing digital image data is a key concern in today’s information-driven society.Effective encryption techniques are required to protect sensitive image data,with the Substitution-box(S-box)often playing a pivotal ... Securing digital image data is a key concern in today’s information-driven society.Effective encryption techniques are required to protect sensitive image data,with the Substitution-box(S-box)often playing a pivotal role in many symmetric encryption systems.This study introduces an innovative approach to creating S-boxes for encryption algorithms.The proposed S-boxes are tested for validity and non-linearity by incorporating them into an image encryption scheme.The nonlinearity measure of the proposed S-boxes is 112.These qualities significantly enhance its resistance to common cryptographic attacks,ensuring high image data security.Furthermore,to assess the robustness of the S-boxes,an encryption system has also been proposed and the proposed S-boxes have been integrated into the designed encryption system.To validate the effectiveness of the proposed encryption system,a comprehensive security analysis including brute force attack and histogram analysis has been performed.In addition,to determine the level of security during the transmission and storage of digital content,the encryption system’s Number of Pixel Change Rate(NPCR),and Unified Averaged Changed Intensity(UACI)are calculated.The results indicate a 99.71%NPCR and 33.51%UACI.These results demonstrate that the proposed S-boxes offer a significant level of security for digital content throughout its transmission and storage. 展开更多
关键词 S-BOX CHAOS artificial bee colony image encryption
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A Mathematical Approach for Generating a Highly Non-Linear Substitution Box Using Quadratic Fractional Transformation
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作者 Abid Mahboob Muhammad Asif +3 位作者 Rana Muhammad Zulqarnain Imran Saddique Hijaz Ahmad Sameh Askar 《Computers, Materials & Continua》 SCIE EI 2023年第11期2565-2578,共14页
Nowadays,one of the most important difficulties is the protection and privacy of confidential data.To address these problems,numerous organizations rely on the use of cryptographic techniques to secure data from illeg... Nowadays,one of the most important difficulties is the protection and privacy of confidential data.To address these problems,numerous organizations rely on the use of cryptographic techniques to secure data from illegal activities and assaults.Modern cryptographic ciphers use the non-linear component of block cipher to ensure the robust encryption process and lawful decoding of plain data during the decryption phase.For the designing of a secure substitution box(S-box),non-linearity(NL)which is an algebraic property of the S-box has great importance.Consequently,the main focus of cryptographers is to achieve the S-box with a high value of non-linearity.In this suggested study,an algebraic approach for the construction of 16×16 S-boxes is provided which is based on the fractional transformation Q(z)=1/α(z)^(m)+β(mod257)and finite field.This technique is only applicable for the even number exponent in the range(2-254)that are not multiples of 4.Firstly,we choose a quadratic fractional transformation,swap each missing element with repeating elements,and acquire the initial S-box.In the second stage,a special permutation of the symmetric group S256 is utilized to construct the final S-box,which has a higher NL score of 112.75 than the Advanced Encryption Standard(AES)S-box and a lower linear probability score of 0.1328.In addition,a tabular and graphical comparison of various algebraic features of the created S-box with many other S-boxes from the literature is provided which verifies that the created S-box has the ability and is good enough to withstand linear and differential attacks.From different analyses,it is ensured that the proposed S-boxes are better than as compared to the existing S-boxes.Further these S-boxes can be utilized in the security of the image data and the text data. 展开更多
关键词 Block cipher S-BOX data security fractional transformation
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Dynamic S-Box Generation Using Novel Chaotic Map with Nonlinearity Tweaking
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作者 Amjad Hussain Zahid Muhammad Junaid Arshad +2 位作者 Musheer Ahmad Naglaa F.Soliman Walid El-Shafai 《Computers, Materials & Continua》 SCIE EI 2023年第5期3011-3026,共16页
A substitution box(S-Box)is a crucial component of contemporary cryptosystems that provide data protection in block ciphers.At the moment,chaotic maps are being created and extensively used to generate these SBoxes as... A substitution box(S-Box)is a crucial component of contemporary cryptosystems that provide data protection in block ciphers.At the moment,chaotic maps are being created and extensively used to generate these SBoxes as a chaotic map assists in providing disorder and resistance to combat cryptanalytical attempts.In this paper,the construction of a dynamic S-Box using a cipher key is proposed using a novel chaotic map and an innovative tweaking approach.The projected chaotic map and the proposed tweak approach are presented for the first time and the use of parameters in their workingmakes both of these dynamic in nature.The tweak approach employs cubic polynomials while permuting the values of an initial S-Box to enhance its cryptographic fort.Values of the parameters are provided using the cipher key and a small variation in values of these parameters results in a completely different unique S-Box.Comparative analysis and exploration confirmed that the projected chaoticmap exhibits a significant amount of chaotic complexity.The security assessment in terms of bijectivity,nonlinearity,bits independence,strict avalanche,linear approximation probability,and differential probability criteria are utilized to critically investigate the effectiveness of the proposed S-Box against several assaults.The proposed S-Box’s cryptographic performance is comparable to those of recently projected S-Boxes for its adaption in real-world security applications.The comparative scrutiny pacifies the genuine potential of the proposed S-Box in terms of its applicability for data security. 展开更多
关键词 Substitution-box chaotic map data security tweaking
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Synthesis and Crystal Structure of Methyl 2-(Diphenylamino)-4-phenyl-1,3-thiazole-5-carboxylate
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作者 Ali Souldozi Seyed Hamid Reza Shojaei +2 位作者 Ali Ramazani Katarzyna lepokura Tadeusz Lis 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2013年第1期82-88,共7页
The title compound, methyl 2-(diphenylamino)-4-phenyl-1,3-thiazole-5-carboxylate, was synthesized and studied by single-crystal X-ray diffraction method. The structure of the product was confirmed by IR, 1H- and 13C... The title compound, methyl 2-(diphenylamino)-4-phenyl-1,3-thiazole-5-carboxylate, was synthesized and studied by single-crystal X-ray diffraction method. The structure of the product was confirmed by IR, 1H- and 13C-NMR spectroscopy and elemental analysis. These experimental studies were supported by quantum mechanical calculations. The structure was solved in monoclinic, space group P21/c with a = 9.573(3), b = 19.533(7), c = 9.876(3), β = 92.35(4)°, V = 1845.2(10)3, T = 85(2) K, Z = 4, R = 0.040 and wR = 0.089 for 6424 observed reflections with I2σ(I). 展开更多
关键词 single-crystal X-ray structure multi-component reaction methyl 2-(diphenylamino)-4-phenyl-1 3-thiazole-5-carboxylate benzoyl isothiocyanate DIPHENYLAMINE dimethyl acetylenedicarboxylate
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Effects of transfected adenovirus-mediated transcription factor X-box binding protein 1 on hippocampal-derived neural stem cell proliferation and apoptosis under hypoxia 被引量:4
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作者 Ying Sha Baohua Liu +3 位作者 Qun Liu Lei Song Jia Fan Yong Liu 《Neural Regeneration Research》 SCIE CAS CSCD 2010年第13期981-986,共6页
BACKGROUND: Neural stem cell (NSC) survival is closely associated with cell apoptosis in ischemic-hypoxic regions following transplantation. Numerous studies have revealed that X-box binding protein 1 (XBP1) is a... BACKGROUND: Neural stem cell (NSC) survival is closely associated with cell apoptosis in ischemic-hypoxic regions following transplantation. Numerous studies have revealed that X-box binding protein 1 (XBP1) is a transcription factor during endoplasmic reticulum unfolded protein response and is essential for cell survival, differentiation, and anti-apoptotic effects. OBJECTIVE: To determine the effects of the XBP1 gene on NSC proliferation and apoptosis under hypoxic conditions following XBP1 gene transfection into rat embryonic hippocampal NSCs using recombinant adenovirus vector. DESIGN, TIME AND SETTING: In vitro experiments were performed at the Laboratory of Cell Biology of Jilin University and Laboratory of Proteomics, Department of Neurology, Jilin University China from September 2008 to November 2009. MATERIALS: Recombinant adenovirus package XBP1 gene and Ad-XBPl-enhanced green fluorescent protein plasmid (Guangzhou Easywin BioMed Technology, China), rabbit anti-XBP1 and its target gene estrogen receptor degradation-enhancing a-mannosidase-like protein (EDEM) glucose-regulated protein 78 (GRP78), anti-apoptotic molecule Bcl-2 and proapoptotic molecule Bax polyclonal antibody (Santa Cruz Biotechnology, Inc., Santa Cruz, CA, USA), and COCI2 (Sigma, St. Louis, MO, USA) were used in the present study. METHODS: Hippocampi from embryonic, Sprague Dawley rats on gestational day 16 were harvested for NSC isolation and cloning, followed by immunofluorescence for Nestin and sub-culturing. The recombinant adenovirus Ad-XBPl-enhanced green fluorescent protein plasmid was transfected into rat embryonic hippocampal NSCs, and then CoCl2 was applied to induce hypoxia. MAIN OUTCOME MEASURES: Cell quantification and 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide colorimetric assay were utilized to detect proliferation in XBPl-transfected NSCs for 7 consecutive days. Western blot assay was utilized to quantify XBP1 GRP78, EDEM, Bcl-2, and Bax expression. Flow cytometry was used to measure apoptosis. RESULTS: NSC proliferation was significantly enhanced following XBP1 gene transfection (P 〈 0.05). Under hypoxic conditions, GRP78, EDEM, and Bcl-2 levels increased, but Bax levels decreased. In addition, NSC apoptosis decreased following transfection (P 〈 0.05). CONCLUSION: The XBP1 gene was successfully transfected into rat embryonic hippocampal NSCs using a recombinant adenovirus vector. NSC proliferation following transfection, as well as anti-apoptotic effects under hypoxia, was significantly increased. 展开更多
关键词 X-box binding protein 1 HYPOXIA apoptosis endoplasmic reticulum stress neural stem cells transplantation nerve growth factor neural regeneration
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Pneumatic Boxing Glove Reduces Upward Drift in Peak Force and Loading Rate over a Long Series of Impacts
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作者 Paul Perkins Alex Jamieson +1 位作者 Wayne Spratford Allan Hahn 《World Journal of Engineering and Technology》 2019年第1期18-53,共36页
A conventional boxing glove and a prototype pneumatic glove were each fitted to a mechanical fist and dropped 253 times from a height of 3 metres on to a force plate covered by an ethylene vinyl acetate (EVA) mat. Imp... A conventional boxing glove and a prototype pneumatic glove were each fitted to a mechanical fist and dropped 253 times from a height of 3 metres on to a force plate covered by an ethylene vinyl acetate (EVA) mat. Impact dynamics were measured and modelled. From the outset, peak impact force and peak rate of force development (loading rate) were lower for the pneumatic glove. For both gloves, these variables displayed upward drift during the drop series, but the drift was smaller for the pneumatic glove. Consequently, the magnitude of the protective effect provided by the pneumatic glove increased with the number of impacts. For the conventional glove, change in peak force showed a close inverse relationship to force plate contact time (R2?>?0.96) and the time from first contact of the glove with the force plate to attainment of peak force (R2?=?0.85). These relationships were much weaker for the pneumatic glove (R2?=?0.09 and 0.59 respectively), suggesting the possibility of a more complex impact damping mechanism. Following the 253 drops of the pneumatic glove, the EVA mat covering the force plate was replaced, and another 10 drops then performed. Peak force readings were immediately reduced to an extent suggesting that 26%?-?34% of the increase that had occurred over the 253 drops was attributable to impact-induced change in mat properties. This has implications for future experimental designs. Overall, the findings provided further evidence of the potential of pneumatic gloves to enable safer boxing. 展开更多
关键词 BOXING SAFETY Low-Impact BOXING GLOVES Modified BOXING PNEUMATIC BOXING GLOVES Protective Equipment for BOXING SPORT Technology SPORT SAFETY
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Thermally decarboxylated sodium bicarbonate:Interactions with water vapour,calorimetric study
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作者 Natalia Volkova Henri Hansson Lennart Ljunggren 《Journal of Pharmaceutical Analysis》 SCIE CAS 2013年第3期193-199,共7页
Isothermal titration calorimetry (ITC) was used to study interactions between water vapour and the surface of thermally converted sodium bicarbonate (NaHCO3). The decarboxyla- tion degree of the samples was varied... Isothermal titration calorimetry (ITC) was used to study interactions between water vapour and the surface of thermally converted sodium bicarbonate (NaHCO3). The decarboxyla- tion degree of the samples was varied from 3% to 35% and the humidity range was 54-100%. The obtained enthalpy values were all exothermic and showed a positive linear correlation with decarboxylation degrees for each humidity studied. The critical humidity, 75% (RHo), was determined as the inflection point on a plot of the mean-AH kJ/mole Na2CO3 against RH. Humidities above the critical humidity lead to complete surface dissolution. The water uptake (m) was determined after each calorimetric experiment, complementing the enthalpy data. A mechanism of water vapour interaction with decarboxylated samples, including the formation of trona and Wegscheider's salt on the bicarbonate surface is proposed for humidities below RHo. 展开更多
关键词 Isothermal titrationcalorimetry Sodium bicarbonate Sodium carbonate Trona salt Wegscheider's salt ENTHALPY Relative humidity Pyrolyticdecarboxylation
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Performance of Prototype Pneumatic Boxing Gloves under Two Different Conditions of Target Padding
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作者 Paul Perkins Alex Jamieson +1 位作者 Wayne Spratford Allan Hahn 《World Journal of Engineering and Technology》 2018年第3期603-624,共22页
The impact damping capabilities of four different boxing gloves were assessed under two different conditions of target padding to determine whether target characteristics might influence previous conclusions concernin... The impact damping capabilities of four different boxing gloves were assessed under two different conditions of target padding to determine whether target characteristics might influence previous conclusions concerning potential for impact mitigation through novel glove design. A conventional 10?oz glove (Std 10?oz), a conventional 16?oz glove (Std 16?oz), a prototype pneumatic glove with a sealed bladder (SBLI) and a prototype pneumatic glove with a bladder allowing air exchange with the external environment (ARLI) were each dropped three times on to a force plate from six heights ranging from 2.5 to 5.0 metres. The force plate was covered by a 50 mm thick mat of EVA material and results obtained were compared with those of an earlier experiment involving use of a similar protocol but a 25 mm thick EVA force plate covering. The thicker mat greatly reduced peak impact forces for all gloves, with values for the Std 10?oz glove becoming much closer to those reported by other researchers for punches delivered by elite boxers to crash test manikins. Peak rates of force development were also substantially decreased. Protective effects provided by the ARLI glove relative to the Std 10?oz glove were diminished but still in the order of 17%?-?22% for peak impact force and 27%?-?49% for peak rate of force development across the range of drop heights. With the 50 mm mat thickness, the SBLI glove was as effective as the ARLI glove in reducing peak impact force, whereas this was not the case with the 25 mm mat. It was, however, always inferior to the ARLI glove in decreasing peak rate of force development. The ability of the ARLI glove to afford protection across a spectrum of impact conditions could yield important practical advantages. 展开更多
关键词 BOXING SAFETY Low-Impact BOXING GLOVES Modified BOXING Protective Equipment for BOXING SPORT Technology SPORT SAFETY
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Effect of Pneumatic Boxing Gloves on Impact Kinematics and Their Relationship to Impact Forces
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作者 Paul Perkins Alex Jamieson +1 位作者 Wayne Spratford Allan Hahn 《World Journal of Engineering and Technology》 2019年第3期472-512,共41页
This study was aimed at improved understanding of the mechanisms of previously reported protective effects of a pneumatic boxing glove. A Motion Capture System was used to obtain velocity data from four different boxi... This study was aimed at improved understanding of the mechanisms of previously reported protective effects of a pneumatic boxing glove. A Motion Capture System was used to obtain velocity data from four different boxing gloves dropped on to a force plate from nine heights ranging from 1 to 5 metres. Two gloves were of the conventional type but differed in mass. The other two were prototype pneumatic gloves. One of these (SBLI) had a sealed bladder while the other (ARLI) incorporated a port allowing air exchange with the external environment. The pneumatic gloves decelerated more slowly than the conventional gloves following impact and compressed through a greater absolute distance. Consequently, they took longer to reach zero velocity. As drop height increased, these trends became more pronounced for the ARLI glove than the SBLI glove. Increase in velocity during rebound was also slower for the pneumatic gloves. The ARLI glove had a lower coefficient of restitution than any of the other gloves at low to moderate drop heights but not at high drop heights. The SBLI glove had a higher coefficient of restitution than the other gloves at all drop heights from 2 metres upwards. This indicated that, overall, the ARLI glove was the most effective, and the SBLI glove the least effective, in dissipating the kinetic energy of impact through conversion to other energy forms. For all gloves at all drop heights, peak positive acceleration at the beginning of rebound was of lower absolute magnitude than peak negative acceleration at the end of compression. The influence of drop height on an index characterising this relationship differed between the conventional and pneumatic gloves, possibly reflecting structural changes to gloves as impact energy increased. The conventional and pneumatic gloves differed regarding temporal alignment between key kinematic and kinetic events, and there were some differences between the two pneumatic gloves in this respect. Nevertheless, peak glove deceleration correlated highly with peak impact force, not only for each glove individually but also when data for all gloves were combined. The findings confirmed the potential practical utility of the ARLI glove and identified air cushion thickness, glove compressibility and capacity for air release and subsequent reuptake as critical aspects of its design. 展开更多
关键词 PNEUMATIC BOXING GLOVES BOXING SAFETY Modified BOXING SPORT SAFETY SPORT Technology Sports Equipment Design Coefficient of RESTITUTION Elas-tic-Plastic Impacts
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Developing a Prototype Piezoelectric Wafer-Box for Optimal Energy Harvesting
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作者 Ahmad S. Seonghoon Kim +2 位作者 Mohammad A. Junan S. Yong B. 《Journal of Civil Engineering and Architecture》 2022年第1期1-12,共12页
Piezoelectric(PZ)energy has been paid attention to as conventional renewable energy sources including solar,wind,and geothermal power.To address the dilemma of climatic conditions affecting the energy harvesting using... Piezoelectric(PZ)energy has been paid attention to as conventional renewable energy sources including solar,wind,and geothermal power.To address the dilemma of climatic conditions affecting the energy harvesting using Lead Zirconate Titanate(PZT)in pavement,wafer-boxes were used with embedded PZT sensors,since wafer-boxes have the ability to be embedded in the pavement where sensors are protected from any kind of physical damage.This research project was designed to identify which shaped wafer-box produced the most electric voltage and power.Various forms of wafer-box were developed to identify if there was any potential difference in voltage generation due to the structural shapes of the box.Seven different shapes of prototype wafer-boxes were designed utilizing both a 3D printer and 3D Computer Aided Design(CAD).These wafer-boxes were coupled with embedded PZT sensors which were tested in asphalt pavement analyzer(APA)machine under certain load to produce electric voltage.Collected voltage data from the APA wheel load test(WLT)were analyzed using various statistical methods.The statistical analyses results indicated that out of the seven different shaped wafer-boxes,the right-angled triangular shaped box produced the highest average voltage values where’s square shaped wafer-box produced the lowest amount of voltage.Structural properties of a wafer-box in terms of section modulus,area moment of inertia,extreme points,and radius of gyration were also analyzed,and a regression analysis was conducted to identify the reasons of different amounts of voltage produced.These voltage values could be used to calculate the power using power formulas showing relationship between power and voltage values.The outcome helped to identify which shape is most effective to power generation under certain circumstances.The regression analysis results indicated that out of four properties the section modulus is the most influential structural property affecting voltage production. 展开更多
关键词 PIEZOELECTRICITY PZT materials voltage wafer-box experiment design section MODULUS
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Efficient Management of Fines in the Stock Flow prior to Headbox in Paper,Board,and Tissue Production
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作者 Jouni Matula Jussi Matula +3 位作者 Jukka Nokelainen Tommi Niskanen Lasse Kauppinen Eemeli Siitonen 《Paper And Biomaterials》 CAS 2022年第1期45-54,共10页
Fines represent a significant volume of biobased wood material and filler,which is of significant importance to sheet quality.New imaging technology reveals the true nature of the behavior of fines in the retention pr... Fines represent a significant volume of biobased wood material and filler,which is of significant importance to sheet quality.New imaging technology reveals the true nature of the behavior of fines in the retention process.This study illustrates new chemical mixing systems,novel and efficient flash mixing methods,and active measurement and automation systems pertaining to efficient management of fines in the stock flow prior to headbox in paper,board,and tissue production,which can reduce additive,fresh water,energy consumption,and the carbon footprint of production to improve sustainability and provide novel opportunities for fines and filler management. 展开更多
关键词 PAPER BOARD fines and fillers HEADBOX flash mixing STOCK camera image technology
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Reflections on Long-Term Development and Use of Automated Scoring Technology in a Sport (Modified Boxing) Context
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作者 Paul Perkins Richard J. N. Helmer +1 位作者 Colin Mackintosh Allan G. Hahn 《World Journal of Engineering and Technology》 2017年第3期455-480,共26页
Technology is being increasingly used to aid judging in sport, but its employment as the primary means of scoring is rare. We have developed and implemented a fully automated scoring system in the context of a modifie... Technology is being increasingly used to aid judging in sport, but its employment as the primary means of scoring is rare. We have developed and implemented a fully automated scoring system in the context of a modified, low-risk form of boxing. The system, which requires contestants to wear vests and gloves incorporating sensor fabrics, has been used in multiple settings over the past five years. During that period, it has undergone progressive iteration guided by action research methodology. Here, we summarise that iteration, reflect on present status and identify possible future directions. We have found that concept of automated scoring has wide appeal, and the wearable technology is almost universally considered comfortable. Nevertheless, some issues remain to be addressed. Use of the technology requires considerable prior and subsequent commitment of time. Apparently valid contacts occasionally fail to score. Causative factors include the configuration of electrical circuitry in the vests and deterioration of that circuitry with repeated vest use and washing. Also, false positive scores are sometimes generated by vest self-shorting and effects of sweat. Many contestants adopt unorthodox styles aimed at exploiting the characteristics of the automated scoring methodology, affecting the aesthetics of the modified sport. There is an expectation that technologically-based scoring should have much greater accuracy than human judging, and should be essentially fail-proof. Disillusionment can occur in?situations where this expectation is not met. We have identified potential?solutions to all the existing issues, with some now being actively explored. Continuation of the quest seems justified by popular dissatisfaction with subjective human judging of boxing and other sports, but we have come to realise that purely technological judging can introduce unforeseen complexities. Our observations could be relevant to various sports interested in the notion of technological judging. 展开更多
关键词 AUTOMATED SCORING TECHNOLOGY Box’Tag Smart Fabric SPORT TECHNOLOGY Wearable Sensors
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Synthesis and Chemical Shifts Calculation of α-Acyloxycarboxamides Derived from Indane-1,2,3-trione by DFT and HF Methods 被引量:3
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作者 Hooriye Yahyaei Ali Reza Kazemizadeh Ali Ramazani 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2012年第9期1346-1356,共11页
α-Acyloxycarboxamides are synthesized from three-component Passerini reaction between indane-1,2,3-trione, isocyanides, and thiophenecarboxylic acids in quantitative yields. The structures of the final products were ... α-Acyloxycarboxamides are synthesized from three-component Passerini reaction between indane-1,2,3-trione, isocyanides, and thiophenecarboxylic acids in quantitative yields. The structures of the final products were confirmed by IR, 1H and 13C NMR spectroscopy, mass spectrometry, and elemental analysis. The B3LYP/HF calculations for computation of 1H and 13C NMR chemical shifts have been carried out for the title compounds at the 6-311+G** and 6-311++G** basis set levels within GIAO and CSGT approaches. Predicted 1H and 13C NMR che-mical shifts have been assigned and compared with experimental 1H and 13C NMR spectra and they are supported each other. 展开更多
关键词 DFT HF NMR spectra Passerini reaction ISOCYANIDE
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Identification and Quantification of Aerosol Polar Oxygenated Compounds Bearing Carboxylic or Hydroxyl Groups.1.Method Development 被引量:5
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作者 Jaoui M. Kleindienst T.E. +1 位作者 Lewandowski M. Edney E.O. 《天然产物研究与开发》 CAS CSCD 2004年第5期409-409,共1页
In this study,a new analytical technique was developed for the identification and quantification of multifunctional compounds containing simultaneously at least one hydroxyl or one carboxylic group,or both.This techni... In this study,a new analytical technique was developed for the identification and quantification of multifunctional compounds containing simultaneously at least one hydroxyl or one carboxylic group,or both.This technique is based on derivatizing first the carboxylic group(s) of the multifunctional compound using an alcohol (e.g.,methanol,1-butanol) in the presence of a relatively strong Lewisacid (BF3) as a catalyst.This esterification reaction quickly and quantitatively converts carboxylic acids to their ester forms.The second step is based on silylation of the ester compounds using bis(trimethylsilyl) trifluoroacetamide (BSTFA) as the derivatizing agent.For compounds bearing ketone groups in addition to carboxylic and hydroxyl groups,a third step was used based on PFBHA derivatizationof the carbonyls.Different parameters including temperature,reaction time,and effect due to artifacts were optimized.A GC/MS in EI and in methane-CI mode was used for the analysis of these compounds.The new approach was tested on a number of multifunctional compounds.The interpretation of their EI (70 eV) and CI mass spectra shows that critical information is gained leading to unambiguous identification of unknown compounds.For example,when derivatized only with BF3-methanol,their mass spectra comprise primary ions at m/z M ·+ +1,M ·+ +29,and M ·+ - 31 for compounds bearing only carboxylic groups and M ·+ +1,M ·+ +29,M ·+ -31,and M ·+ -17 for those bearing hydroxyl andcarboxylic groups.However,when a second derivatization (BSTFA) was used,compounds bearing hydroxyl and carboxylic groups simultaneously show,in addition to the ions observed before,ions at m/z M ·+ +73,M ·+ -15,M ·+ -59,M ·+ -75,M ·+ -89,and 73.To the best of our knowledge,this technique describes systematically for the first time a method for identifying multifunctional oxygenated compounds containing simultaneously one or more hydroxyl and carboxylic acid groups. 展开更多
关键词 气溶胶 氧化物 生物化学 定量分析 参数
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APG: A novel python-based ArcGIS toolbox to generate absence-datasets for geospatial studies 被引量:3
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作者 Seyed Amir Naghibi Hossein Hashemi Biswajeet Pradhan 《Geoscience Frontiers》 SCIE CAS CSCD 2021年第6期90-104,共15页
One important step in binary modeling of environmental problems is the generation of absence-datasets that are traditionally generated by random sampling and can undermine the quality of outputs.To solve this problem,... One important step in binary modeling of environmental problems is the generation of absence-datasets that are traditionally generated by random sampling and can undermine the quality of outputs.To solve this problem,this study develops the Absence Point Generation(APG)toolbox which is a Python-based ArcGIS toolbox for automated construction of absence-datasets for geospatial studies.The APG employs a frequency ratio analysis of four commonly used and important driving factors such as altitude,slope degree,topographic wetness index,and distance from rivers,and considers the presence locations buffer and density layers to define the low potential or susceptibility zones where absence-datasets are generated.To test the APG toolbox,we applied two benchmark algorithms of random forest(RF)and boosted regression trees(BRT)in a case study to investigate groundwater potential using three absence datasets i.e.,the APG,random,and selection of absence samples(SAS)toolbox.The BRT-APG and RF-APG had the area under receiver operating curve(AUC)values of 0.947 and 0.942,while BRT and RF had weaker performances with the SAS and Random datasets.This effect resulted in AUC improvements for BRT and RF by 7.2,and 9.7%from the Random dataset,and AUC improvements for BRT and RF by 6.1,and 5.4%from the SAS dataset,respectively.The APG also impacted the importance of the input factors and the pattern of the groundwater potential maps,which proves the importance of absence points in environmental binary issues.The proposed APG toolbox could be easily applied in other environmental hazards such as landslides,floods,and gully erosion,and land subsidence. 展开更多
关键词 Absence-dataset Classification Python Machine learning algorithms GIS Groundwater HYDROGEOLOGY
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A Matlab/Simulink-Based Photovoltaic Array Model Employing SimPowerSystems Toolbox 被引量:1
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作者 Samer Said Ahmed Massoud +1 位作者 Mohieddine Benammar Shehab Ahmed 《Journal of Energy and Power Engineering》 2012年第12期1965-1975,共11页
关键词 Simulink 光伏阵列 V模型 MATLAB 工具箱 最大功率点跟踪 MATLAB 电力系统仿真
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Optimization of operating conditions in the steam turbine blade cascade using the black-box method
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作者 Vahid Sadrian Esmail Lakzian +3 位作者 Davood Hoseinzade Behrad Haghighi M.M.Rashidi Heuy Dong Kim 《Propulsion and Power Research》 SCIE 2023年第4期467-485,共19页
Water droplets cause corrosion and erosion,condensation loss,and thermal efficiency reduction in low-pressure steam turbines.In this study,multi-objective optimization was carried out using the black-box method throug... Water droplets cause corrosion and erosion,condensation loss,and thermal efficiency reduction in low-pressure steam turbines.In this study,multi-objective optimization was carried out using the black-box method through the automatic linking of a genetic algorithm(GA)and a computational fluid dynamics(CFD)code to find the optimal values of two design variables(inlet stagnation temperature and cascade pressure ratio)to reduce wetness in the last stages of turbines.The wet steam flow numerical model was used to calculate the optimization parameters,including wetness fraction rate,mean droplet radius,erosion rate,condensation loss rate,kinetic energy rate,and mass flow rate.Examining the validation results showed a good agreement between the experimental data and the numerical outcomes.According to the optimization results,the inlet stagnation temperature and the cascade pressure ratio were proposed to be 388.67(K)and 0.55(-),respectively.In particular,the suggested optimaltemperature and pressure ratio improved the liquid mass fraction and mean droplet radius by about 32%and 29%,respectively.Also,in the identified optimal operating state,the ratios of erosion,condensation loss,and kinetic energy fell by 76%,32.7%,and 15.85%,respectively,while the mass flow rate ratio rose by 0.68%. 展开更多
关键词 Black-box optimization Wet steam flow Steam turbine cascade Erosion rate Condensation loss
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6例肾尤文肉瘤伴静脉瘤栓的诊治
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作者 王滨帅 邱敏 +6 位作者 张前进 田茂锋 刘磊 王国良 陆敏 田晓军 张树栋 《北京大学学报(医学版)》 CAS CSCD 北大核心 2024年第4期636-639,共4页
目的:回顾和分析肾尤文肉瘤伴静脉瘤栓患者的临床诊治过程,随访患者的生存预后,为疾病的诊治提供帮助。方法:收集2016年6月至2022年6月在北京大学第三医院诊断为肾尤文肉瘤伴静脉瘤栓患者的临床资料,包括一般资料、手术资料和术后病理资... 目的:回顾和分析肾尤文肉瘤伴静脉瘤栓患者的临床诊治过程,随访患者的生存预后,为疾病的诊治提供帮助。方法:收集2016年6月至2022年6月在北京大学第三医院诊断为肾尤文肉瘤伴静脉瘤栓患者的临床资料,包括一般资料、手术资料和术后病理资料,电话随访患者预后情况,分析诊治过程对疾病预后的影响。结果:患者6例,其中男性1例、女性5例;左肾肿物4例,右肾肿物2例;确诊时中位年龄28岁(16~52岁);影像学表现均为外生性肿瘤,内部存在坏死组织及出血;平均肿瘤最大直径为12.6 cm,平均瘤栓长度为7.8 cm;4例行开放手术,2例行腹腔镜手术;术后病理结果均为肾尤文肉瘤,免疫组织化学结果中3例CD99(+),2例FLI-1(+),1例CD99、FLI-1(-);术后接受化疗(环磷酰胺、多柔比星、长春新碱/异环磷酰胺、依托泊苷方案)3例,化疗联合放疗1例,未行放化疗2例;术后6例平均总体生存率(overall survival,OS)为37个月,接受化疗的4例患者平均术后OS(47个月)显著高于未行化疗的2例患者(16个月,P=0.031)。结论:肾尤文肉瘤伴静脉瘤栓临床罕见,年轻女性患者多发,手术难度大,预后不良,手术切除加辅助放化疗可提高患者OS。 展开更多
关键词 肾肿瘤 尤文肉瘤 静脉瘤栓
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中华传统摔跤术的非物质文化遗产保护研究
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作者 徐泉森 徐帆 张鑫杰 《当代体育科技》 2024年第15期124-126,共3页
中华传统摔跤术是我国各民族同胞在生产生活实践中创造出来的以摔柔技法为主的格斗技艺,是我国传统文化之中最具中华民族文化识别性的非物质文化遗产。该研究采用文献资料等方法,从非物质文化遗产的视角对各类传统摔跤术的保护情况进行... 中华传统摔跤术是我国各民族同胞在生产生活实践中创造出来的以摔柔技法为主的格斗技艺,是我国传统文化之中最具中华民族文化识别性的非物质文化遗产。该研究采用文献资料等方法,从非物质文化遗产的视角对各类传统摔跤术的保护情况进行深入分析,研究结果发现,现今多个跤种入选了国家、省级等各级非物质文化遗产名录,这些跤种主要分为竞技与展演两大类,各类摔跤术入选非物质文化遗产保护名录对于其跤种的发展与传承起到了重要作用。同时,根据当前传统文化发展的时代需求,提出在中华传统摔跤术的非物质文化遗产保护过程中,要进行数字化保护建设、重视活态传承、对实体文化进行保护、做好档案建设等发展建议。 展开更多
关键词 中华 摔跤术 非物质文化 遗产保护
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