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The relationship between compartment models and their stochastic counterparts:A comparative study with examples of the COVID-19 epidemic modeling
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作者 Ziyu Zhao Yi Zhou +6 位作者 Jinxing Guan Yan Yan Jing Zhao Zhihang Peng Feng Chen Yang Zhao Fang Shao 《Journal of Biomedical Research》 CAS CSCD 2024年第2期175-188,I0016-I0018,共17页
Deterministic compartment models(CMs)and stochastic models,including stochastic CMs and agent-based models,are widely utilized in epidemic modeling.However,the relationship between CMs and their corresponding stochast... Deterministic compartment models(CMs)and stochastic models,including stochastic CMs and agent-based models,are widely utilized in epidemic modeling.However,the relationship between CMs and their corresponding stochastic models is not well understood.The present study aimed to address this gap by conducting a comparative study using the susceptible,exposed,infectious,and recovered(SEIR)model and its extended CMs from the coronavirus disease 2019 modeling literature.We demonstrated the equivalence of the numerical solution of CMs using the Euler scheme and their stochastic counterparts through theoretical analysis and simulations.Based on this equivalence,we proposed an efficient model calibration method that could replicate the exact solution of CMs in the corresponding stochastic models through parameter adjustment.The advancement in calibration techniques enhanced the accuracy of stochastic modeling in capturing the dynamics of epidemics.However,it should be noted that discrete-time stochastic models cannot perfectly reproduce the exact solution of continuous-time CMs.Additionally,we proposed a new stochastic compartment and agent mixed model as an alternative to agent-based models for large-scale population simulations with a limited number of agents.This model offered a balance between computational efficiency and accuracy.The results of this research contributed to the comparison and unification of deterministic CMs and stochastic models in epidemic modeling.Furthermore,the results had implications for the development of hybrid models that integrated the strengths of both frameworks.Overall,the present study has provided valuable epidemic modeling techniques and their practical applications for understanding and controlling the spread of infectious diseases. 展开更多
关键词 compartment models agent-based models compartment-agent mixed models comparative study COVID-19
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Comparative efficacy of proximal femoral nail vs dynamic condylar screw in treating unstable intertrochanteric fractures
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作者 Ahmed Mohamed Yousif Mohamed Monzir Salih +2 位作者 Mohanad Abdulgadir Ayman E Abbas Duha Lutfi Turjuman 《World Journal of Orthopedics》 2024年第8期796-806,共11页
BACKGROUND Among the most frequent hip fractures are trochanteric fractures,which usually occur from low-energy trauma like minor falls,especially in older people with osteoporotic bones.AIM To evaluate the treatment ... BACKGROUND Among the most frequent hip fractures are trochanteric fractures,which usually occur from low-energy trauma like minor falls,especially in older people with osteoporotic bones.AIM To evaluate the treatment efficacy of dynamic condylar screws(DCS)and proximal femoral nails(PFN)for unstable intertrochanteric fractures.METHODS To find pertinent randomized controlled trials and retrospective observational studies comparing PFN with DCS for the management of unstable femoral intertrochanteric fractures,a thorough search was carried out.For research studies published between January 1996 and April 2024,PubMed,EMBASE,Scopus,Web of Science,Cochrane Library,and Google Scholar were all searched.The complete texts of the papers were retrieved,vetted,and independently examined by two investigators.Disputes were settled by consensus,and any disagreements that persisted were arbitrated by a third author.RESULTS This study included six articles,comprising a total of 173 patients.Compared to the DCS,the PFN had a shorter operation time[mean difference(MD):-41.7 min,95%confidence interval(95%CI):-63.04 to-20.35,P=0.0001],higher success rates with closed reduction techniques[risk ratio(RR):34.05,95%CI:11.12-104.31,P<0.00001],and required less intraoperative blood transfusion(MD:-1.4 units,95%CI:-1.80 to-1.00,P<0.00001).Additionally,the PFN showed shorter fracture union time(MD:-6.92 wk,95%CI:-10.27 to-3.57,P<0.0001)and a lower incidence of reoperation(RR:0.37,95%CI:0.17-0.82,P=0.01).However,there was no discernible variation regarding hospital stay,implant-related complications,and infections.CONCLUSION Compared to DCS,PFN offers shorter operative times,reduces the blood transfusions requirements,achieves higher closed reduction success,enables faster fracture healing,and lowers reoperation incidence. 展开更多
关键词 Intertrochanteric fracture UNSTABLE Dynamic condylar screw Proximal femoral nail META-ANALYSIS comparative study
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Exploring Nominalization in English Abstracts of Applied Linguistics Research Articles:A Comparative Study Between Chinese and International Journals
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作者 Gong Yingrui Zhao Yibu 《Contemporary Social Sciences》 2024年第4期122-142,共21页
Researchers around the world strive to communicate new knowledge,primarily via publication,with the abstract being crucial in conveying core insights.Previous research has generally analyzed the discourse features of ... Researchers around the world strive to communicate new knowledge,primarily via publication,with the abstract being crucial in conveying core insights.Previous research has generally analyzed the discourse features of abstracts from a macro perspective and often employed either outdated texts,such as those over a decade old,or papers written by authors with lower English academic writing proficiency as research material.In this study,we analyzed forty abstracts from leading journals in applied linguistics,evenly split between Chinese and international journals.It revealed that the use of nominalization in abstracts by Chinese and international scholars showed similarities due to the universal academic requirement for conciseness.However,due to cultural and educational differences,each group differed in their respective language choices and nominalization usage.By analyzing the application of nominalization in different cultural contexts,the results of our study offered practical suggestions for crafting abstracts that effectively convey information,thereby,contributing to the broader academic community. 展开更多
关键词 NOMINALIZATION ABSTRACTS comparative study applied linguistics
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A Comparative Study on Factors Influencing Food Security in China and India
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作者 Shaowen YANG Meixue QIU 《Asian Agricultural Research》 2024年第2期12-15,共4页
This paper analyzes and compares the key factors influencing food security in two populous countries(China and India),and cate-gorizes them into three types:agricultural production,economic development and income leve... This paper analyzes and compares the key factors influencing food security in two populous countries(China and India),and cate-gorizes them into three types:agricultural production,economic development and income level,and income distribution.Using the prevalence of undernourishment as an indicator of food security,the paper empirically tests the degree of impact of various factors on food security in both countries using Tobit regression and Newey regression methods.The study finds that improving the level of economic development can significantly enhance food security in both countriesꎻreducing the Gini coefficient has a significant impact on India,but not on Chinaꎻincreasing the agricultural production per capita has a much greater effect on China than on India.Therefore,both countries should take measures that are both similar and different according to their national conditions to improve their food security level. 展开更多
关键词 Food security Influencing factors comparative study Econometric model
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Quantitative Comparative Study of the Performance of Lossless Compression Methods Based on a Text Data Model
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作者 Namogo Silué Sié Ouattara +1 位作者 Mouhamadou Dosso Alain Clément 《Open Journal of Applied Sciences》 2024年第7期1944-1962,共19页
Data compression plays a key role in optimizing the use of memory storage space and also reducing latency in data transmission. In this paper, we are interested in lossless compression techniques because their perform... Data compression plays a key role in optimizing the use of memory storage space and also reducing latency in data transmission. In this paper, we are interested in lossless compression techniques because their performance is exploited with lossy compression techniques for images and videos generally using a mixed approach. To achieve our intended objective, which is to study the performance of lossless compression methods, we first carried out a literature review, a summary of which enabled us to select the most relevant, namely the following: arithmetic coding, LZW, Tunstall’s algorithm, RLE, BWT, Huffman coding and Shannon-Fano. Secondly, we designed a purposive text dataset with a repeating pattern in order to test the behavior and effectiveness of the selected compression techniques. Thirdly, we designed the compression algorithms and developed the programs (scripts) in Matlab in order to test their performance. Finally, following the tests conducted on relevant data that we constructed according to a deliberate model, the results show that these methods presented in order of performance are very satisfactory:- LZW- Arithmetic coding- Tunstall algorithm- BWT + RLELikewise, it appears that on the one hand, the performance of certain techniques relative to others is strongly linked to the sequencing and/or recurrence of symbols that make up the message, and on the other hand, to the cumulative time of encoding and decoding. 展开更多
关键词 Arithmetic Coding BWT Compression Ratio comparative Study Compression Techniques Shannon-Fano HUFFMAN Lossless Compression LZW PERFORMANCE REDUNDANCY RLE Text Data Tunstall
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Comparative Study of the Reliability and Complexity of Symmetrical and Asymmetrical Cryptosystems for the Protection of Academic Data in the Democratic Republic of Congo
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作者 Mugaruka Buduge Gulain Jeremie Ndikumagenge +2 位作者 Buhendwa Nyenyezi Justin Bulonza Masumbuko Alexis Katho Seba Jacques 《Journal of Information Security》 2024年第3期299-307,共9页
In the digital age, the data exchanged within a company is a wealth of knowledge. The survival, growth and influence of a company in the short, medium and long term depend on it. Indeed, it is the lifeblood of any mod... In the digital age, the data exchanged within a company is a wealth of knowledge. The survival, growth and influence of a company in the short, medium and long term depend on it. Indeed, it is the lifeblood of any modern company. A companys operational and historical data contains strategic and operational knowledge of ever-increasing added value. The emergence of a new paradigm: big data. Today, the value of the data scattered throughout this mother of knowledge is calculated in billions of dollars, depending on its size, scope and area of intervention. With the rise of computer networks and distributed systems, the threats to these sensitive resources have steadily increased, jeopardizing the existence of the company itself by drying up production and losing the interest of customers and suppliers. These threats range from sabotage to bankruptcy. For several decades now, most companies have been using encryption algorithms to protect and secure their information systems against the threats and dangers posed by the inherent vulnerabilities of their infrastructure and the current economic climate. This vulnerability requires companies to make the right choice of algorithms to implement in their management systems. For this reason, the present work aims to carry out a comparative study of the reliability and effectiveness of symmetrical and asymmetrical cryptosystems, in order to identify one or more suitable for securing academic data in the DRC. The analysis of the robustness of commonly used symmetric and asymmetric cryptosystems will be the subject of simulations in this article. 展开更多
关键词 comparative Study CRYPTOSYSTEMS Symmetric Encryption Asymmetric Encryption
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Comparative studies of critical physiological limits and vulnerability to environmental extremes in small ectotherms:How much environmental control is needed?
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作者 Ary A.HOFFMANN Carla M.SGRÒ 《Integrative Zoology》 SCIE CSCD 2018年第4期355-371,共17页
Researchers and practitioners are increasingly using comparative assessments of critical thermal and physiological limits to assess the relative vulnerability of ectothermic species to extreme thermal and aridity cond... Researchers and practitioners are increasingly using comparative assessments of critical thermal and physiological limits to assess the relative vulnerability of ectothermic species to extreme thermal and aridity conditions occurring under climate change.In most assessments of vulnerability,critical limits are compared across taxa exposed to different environmental and developmental conditions.However,many aspects of vulnerability should ideally be compared when species are exposed to the same environmental conditions,allowing a partitioning of sources of variation such as used in quantitative genetics.This is particularly important when assessing the importance of different types of plasticity to critical limits,using phylogenetic analyses to test for evolutionary constraints,isolating genetic variants that contribute to limits,characterizing evolutionary interactions among traits limiting adaptive responses,and when assessing the role of cross generation effects.However,vulnerability assessments based on critical thermal/physiological limits also need to take place within a context that is relevant to field conditions,which is not easily provided under controlled environmental conditions where behavior,microhabitat,stress exposure rates and other factors will differ from field conditions.There are ways of reconciling these requirements,such as by taking organisms from controlled environments and then testing their performance under field conditions(or vice versa).While comparisons under controlled environments are challenging for many taxa,assessments of critical thermal limits and vulnerability will always be incomplete unless environmental effects within and across generations are considered,and where the ecological relevance of assays measuring critical limits can be established. 展开更多
关键词 comparative studies common garden critical limits ECTOTHERMS environmental control thermal limits stress resistance
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Comparative Textual Studies on Bai Hua's Poem Xiatian Hai Hen Yuan and Its English Translations
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作者 杨安文 牟厚宇 《海外英语》 2020年第12期35-37,共3页
Based on the poem Xiatian Hai Hen Yuan夏天还很远, one of the most characteristic works of the Chinese poet Bai Hua, along with its four English translations, this paper conducts comparative textual studies with regard... Based on the poem Xiatian Hai Hen Yuan夏天还很远, one of the most characteristic works of the Chinese poet Bai Hua, along with its four English translations, this paper conducts comparative textual studies with regard to three aspects, including the translation of hidden personae, the selection of the tense and aspectas well as the rendition of poetic rhythms. The author holds the view that, on the one hand, different textual interpretations have gone a long way toward the dissemination of the original poem in the English-speaking world;on the other hand, the translator's proper understanding and rendition is of great significance with a view to a better presentation of the unique beauty of Chinese poetry both in the content and the form. 展开更多
关键词 Bai Hua Xiatian Hai Hen Yuan夏天还很远 English translations comparative textual studies
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A comparative study of the main factors controlling geohazards induced by 10 strong earthquakes in Western China since the Wenchuan earthquake in 2008 被引量:1
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作者 Chao Peng Zhi-qiang Yin +2 位作者 Xu-jiao Zhang Hai Shao Ming-fei Pang 《China Geology》 CAS CSCD 2023年第1期70-84,共15页
Determining the main controlling factors of earthquake-triggered geohazards is a prerequisite for studying earthquake geohazards and post-disaster emergency response.By studying these factors,the geomorphic and geolog... Determining the main controlling factors of earthquake-triggered geohazards is a prerequisite for studying earthquake geohazards and post-disaster emergency response.By studying these factors,the geomorphic and geological factors controlling the nature,condition,and distribution of earthquake-induced geohazards can be analyzed.Such insights facilitate earthquake disaster prediction and emergency response planning.The authors combined field investigations and spatial data analysis to examine geohazards induced by seismic events,examining ten earthquakes including the Wenchuan,Yushu,Lushan events,to elucidate the main control factors of seismic geohazard.The authors observed that seismic geohazard occurrence is usually affected by many factors,among which active nature of the seismogenic fault,seismic peak ground acceleration(PGA),topographic slope and geomorphic height differences,and distance from the fault zone and river system are the most important.Compared with strike-slip earthquakes,thrust earthquakes induce more high-altitude and high-speed remote landslides,which can cause great harm.Slopes of 0°–40°are prone to secondary seismic geohazards,which are mainly concentrated 0–6 km from the river system.Secondary geohazards are not only related to seismogenic fault but also influenced by the associated faults in the earthquake area.The maximum seismic PGA and secondary seismic geohazard number are positively correlated,and the horizontal and vertical ground motions play leading and promoting roles in secondary geohazard formation,respectively.Through the research,the spatial distribution of seismic geohazards is predicted,providing a basis for the formulation of emergency response plans following disasters. 展开更多
关键词 Wenchuan earthquake GEOHAZARDS Main control factors comparative study Geological disater survey engineering Western China
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Helicobacter Pylori Infection and Gastroduodenal Lesions in Patients with Chronic Kidney Disease: A Comparative Study
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作者 Winnie T. Bekolo Nga Servais A. F. Eloumou Bagnaka +10 位作者 Nancy Halle-Ekane Antonin Ndjitoyap Ndam Guy R. Senga Ndjapa Hermine Fouda Lionel P. J. Elimby Ngande Agnès Malongue Dominique Noah Noah Mathurin Kowo Firmin Ankouane Andoulo Henry N. Luma Marie P. Halle-Ekane 《Open Journal of Gastroenterology》 CAS 2023年第1期49-60,共12页
Introduction: Gastroduodenal lesions are common in chronic kidney disease (CKD). They are linked to various factors including Helicobacter pylori infection (H. pylori). Few data are available in Africa on H. pylori in... Introduction: Gastroduodenal lesions are common in chronic kidney disease (CKD). They are linked to various factors including Helicobacter pylori infection (H. pylori). Few data are available in Africa on H. pylori infection and chronic kidney disease. The aim of this study was to assess the impact of H. pylori infection and to describe the gastroduodenal lesions found in patients with chronic kidney disease. Patients and Methods: A cross-sectional study was conducted, February 1<sup>st</sup> to May 31<sup>st</sup>, 2021, at the Douala General Hospital in Cameroon. We included patients with CKD classified as stages 3 to 5 according KDIGO classification, on hemodialysis or not, who agreed to participate in the study. They were matched with a “control” population including patients with normal renal function according to sex and age (ratio 1:2). Patients on antibiotics and/or proton pump inhibitors were excluded. We collected data from CKD patients and from medical records for non-CKD group. Each patient underwent an upper digestive endoscopy and identification of H. pylori using a urease rapid test. Logistic regression was used to identify independent associations for a significance level set at p Results: We included 99 patients including 33 with CKD and 66 control patients. Among patients with CKD, the predominance was male (n = 18/33 or 54.5%). The mean age was 51.2 ± 12.8 years. Arterial hypertension was the first etiology of CKD (n = 13 or 39.4%). The prevalence of H. pylori in patients with CKD was 63.6% versus 37.9% in control patients (p-value = 0.015). The main endoscopic lesions were erosive gastropathy (n = 14 or 42.4%) and erythematous gastropathy (n = 7 or 21.2%). Patients with CKD were 5 times more likely to have H. pylori infection (OR = 5.69;CI 95% 0.14 - 0.82;p = 0.017). Factors associated with H. pylori infection were chronic kidney disease (aOR = 1.02;CI 95% 0.14 - 0.82;p = 0.017) and hemodialysis (aOR = 10;CI 95% 1.08 - 91.9;p = 0.042). Conclusion: The prevalence of H. pylori infection is higher in patients with CKD. Endoscopic lesions are inflammatory. Factors associated with H. pylori infection are chronic kidney disease and hemodialysis. 展开更多
关键词 Chronic Kidney Disease H. Pylori Gastroduodenal Lesions comparative Study Cameroon
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A Comparative Study on the Communication of“Friendly Shandong”Official Account on Different Short Video Platforms
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作者 CHEN Fangying LI Xichao 《Journal of Landscape Research》 2023年第3期47-50,共4页
Taking“Friendly Shandong”official account as an example,the relevant data of the account on the four platforms of Tiktok,Kwai,Bilibili and Little Red Book were comparatively analyzed to study the influence of short ... Taking“Friendly Shandong”official account as an example,the relevant data of the account on the four platforms of Tiktok,Kwai,Bilibili and Little Red Book were comparatively analyzed to study the influence of short video on the communication of Shandong tourism image.The research mainly included two aspects:fan persona features and interactive effects.Through comparative study,it will provide a reference for the operation team of“Friendly Shandong”official account to spread the tourism image of Shandong with different platforms. 展开更多
关键词 Friendly Shandong Short video platform COMMUNICATION comparative study
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Radiation Exposure during Dynamic Hip Screw Fixation: A Comparative Study
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作者 Islam Sarhan Ramy Shehata Neil Ashwood 《Open Journal of Orthopedics》 2023年第3期78-83,共7页
Background: The safe amount of radiation permissible during fixation of neck of femur fractures has long been studied. Factors including surgeons’ experience have been highlighted. We aimed in this study to compare d... Background: The safe amount of radiation permissible during fixation of neck of femur fractures has long been studied. Factors including surgeons’ experience have been highlighted. We aimed in this study to compare different factors for quality and safety improvement. Methods: It was a retrospective study, including all patients who had undergone a standard DHS fixation between January 2018 and June 2019 for inter-trochanteric neck of femur fractures. Two groups were stratified;(Group A) had the procedure performed by a specialist non-consultant surgeon (NCG) and (Group B) by an established consultant (CG). The Dose Area Product (DAP) and the duration of radiation exposure were recorded. Results: Over a period of 18 months, 91 cases were included with a mean age of 82 years old. The mean weight was 62 kg. 42 patients had complex fractures, and 49 patients had simple fractures. 12% of patients were ASA II, 70% of cases were ASA III and 18% of the patients were ASA IV. The mean DAP for group A was 345.131 CGYCM2 (SD 273.65) and for group B 234.63 CGYCM2 (SD 165.30). The time of exposure was 8.6 sec and 13.16 sec in groups B and A respectively. Conclusion: The data collected from this study were comparable to others. The amount of radiation exposure was of difference related to the decision-making intra-operatively. Other factors were not statistically significant. 展开更多
关键词 DHS Radiation Exposure comparative Study Neck of Femur Fracture
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A Comparative Study on Verb-Noun Collocation Errors of Chinese EFL Learners with Different Language Proficiency
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作者 WANG Yi-yin CHEN Ying-rong 《Journal of Literature and Art Studies》 2023年第8期585-592,共8页
This study presents a comparative analysis of verb-noun collocation errors made by Chinese EFL learners with different language proficiency.Linguistic data from two sub-corpora of CLEC(Chinese Learner English Corpus,G... This study presents a comparative analysis of verb-noun collocation errors made by Chinese EFL learners with different language proficiency.Linguistic data from two sub-corpora of CLEC(Chinese Learner English Corpus,Gui&Yang,1999)consist of the compositions written freely by Chinese senior high school students(ST2)and the 3rd-and 4th-year English majors of Chinese universities(ST6).The study results show that four types of verb-noun collocation errors are frequently made due to incorrect L1 translation,misuse of relative synonyms,misuse of delexical verbs,and misuse of part of speech;the number of errors decreases with the development of language proficiency,especially errors by incorrect L1 translation and relative synonyms.And for both ST2 and ST6 EFL learners,errors resulted from incorrect L1 translation account for nearly a half with the same high-frequency words.It is also found that ST6 learners’competence in collocation and synonym identification doesn’t grow with the increase of their vocabulary,as is shown in the case of overusing delexical verbs in collocation,the same error made by ST2 learners,who have a significantly weaker command of delexical verbs.Implications of the findings are also discussed with the purpose of raising the awareness of collocation pedagogy and enhancing EFL learners’collocation competence. 展开更多
关键词 verb-noun collocation errors CLEC Chinese EFL learners a comparative study
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A Comparative Study of YīJiàn Xiǎo Shìand A Small Incident Rendered by the Yangs
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作者 WANG Zai-jun ZHANG Jun-feng ZHANG Shun-sheng 《Journal of Literature and Art Studies》 2023年第11期825-830,共6页
Lu Xun’s short stories play a prominent role in the history of modern Chinese literature,and a number of Sinologists have studied them and published their English translations.This paper selects“YīJiàn Xiǎo S... Lu Xun’s short stories play a prominent role in the history of modern Chinese literature,and a number of Sinologists have studied them and published their English translations.This paper selects“YīJiàn Xiǎo Shì”in Lu Xun’s collection“Call to Arms”as the object of study,taking hypotaxis and parataxis as the starting point,and compares the translation of Yang Hsien-yi and Gladys Yang with the original version,studying the differences between the them in the process of C-E translation.It is hoped that some flexible conversion strategies in English-Chinese translation can be learned from the translation research. 展开更多
关键词 YīJiàn Xiǎo Shì A Small Incident rendered by Yang Hsien-yi&Gladys Yang hypotaxis and parataxis comparative study
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The Comparative Study of Chuangtse’s English Translations Under the Theory of Spirit Transmission and Meaning Conveyance
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作者 QIN Xiaowan PENG Keming 《Cultural and Religious Studies》 2023年第4期183-186,共4页
Cultural-loaded word is one of the most popular topics in translation studies.The theory of spirit transmission and meaning conveyance provides a new way for the translation of cultural-loaded word.Based on the A Happ... Cultural-loaded word is one of the most popular topics in translation studies.The theory of spirit transmission and meaning conveyance provides a new way for the translation of cultural-loaded word.Based on the A Happy Excursion,this paper makes a comparative analysis of the translation strategies of seven English versions.This study will reveal the similarities and differences between Chinese and foreign translators’translation strategies. 展开更多
关键词 Chuangtse spirit transmission and meaning conveyance comparative study
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A Comparative Study of British Gentleman Culture and American Cowboy Culture
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作者 YANG Weiying 《Sino-US English Teaching》 2023年第9期381-384,共4页
This paper makes a comparative analysis by selecting British gentleman culture and American cowboy culture,the two distinctive cultures,to trace their roots,explore their connotations,and search for their similarities... This paper makes a comparative analysis by selecting British gentleman culture and American cowboy culture,the two distinctive cultures,to trace their roots,explore their connotations,and search for their similarities and differences,so as to better understand the respective characteristics of British and American cultures.The result shows that although the two cultures have different styles,which can interpret two different ethnic cultures,they are related by blood and have certain commonalities. 展开更多
关键词 British gentleman culture American cowboy culture comparative study
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Comparative Study of Available Solar Potential for Six Stations of Sahel
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作者 Serigne Abdoul Aziz Niang Ahmed Gueye +3 位作者 Astou Sarr Dialo Diop Saka Goni Bado Nebon 《Smart Grid and Renewable Energy》 2023年第8期153-167,共15页
Sahel is an African area with high solar potential. However, this potential is not uniform across the region. This paper examines the spatial distribution of the available solar potential by using six stations across ... Sahel is an African area with high solar potential. However, this potential is not uniform across the region. This paper examines the spatial distribution of the available solar potential by using six stations across the Sahel area. This comparative study was based on the analysis of in situ measurements in Dakar in Senegal, Niamey in Niger, Ouagadougou, Gaoua, Dori in Burkina Faso and N’Djamena in Chad. The results showed the presence of a good global solar potential with an average value of about 5.43 kWh/m<sup>2</sup>/day. The maxima of global potential are noted in the northern part in Niamey with a value of 6.24 kWh/m<sup>2</sup>/day while the minima are recorded in the south-eastern part in N’Djamena with an irradiation close to 4.71 kWh/m<sup>2</sup>/day. Then, the monthly evolution of this potential shows similar trends for all stations. Indeed, two maximums are observed during the year in Spring (March) and Autumn (October). However, for most of these stations, the minima of global potential are recorded in Winter (November, February) and during the rainy season (July, October). Moreover, the direct normal potential also shows seasonal trends for the two stations (Dakar, Niamey) where it was measured. The maxima of direct normal irradiation (DNI) are observed between February and May with a value of 5.5 kWh/m<sup>2</sup>/day in Dakar and in Niamey with a value around 5.32 kWh/m<sup>2</sup>/day between February and November. 展开更多
关键词 Solar Potential PYRANOMETER SAHEL comparative Study Sunlight Analysis
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Vocational Education from a Cross-national Perspective:Comparative Analysis of China,Germany,and the United States,with a Case Study of Zhaixing
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作者 Xiyan Li Chen Chen Peishi Wu 《Journal of Educational Theory and Management》 2023年第1期21-26,共6页
This study delves into the current state and challenges of vocational education through a comparative study of cross-national vocational education and an analysis of the Zhaixing Academy case.The research reveals that... This study delves into the current state and challenges of vocational education through a comparative study of cross-national vocational education and an analysis of the Zhaixing Academy case.The research reveals that vocational education reform can draw on the experiences of the German dual system,American community colleges,and Chinese vocational education reforms,with a focus on informal education pathways,practice-oriented teaching,and flexible training methods.The Zhaixing Academy case demonstrates the application of practice-oriented teaching approaches in the field of vocational education,emphasizing individual student development needs and the advantages of education outside formal institutions,offering new insights and references for the current Chinese education system.The study proposes that governments and education departments should increase investment in vocational education,encourage collaboration between enterprises and vocational education institutions,and support innovative practice-oriented education.In the future,Zhaixing Academy can continue to focus on education reform,expand the realm of practice-oriented education,promote its educational philosophy and methods,and contribute to the diversification and sustainable development of education. 展开更多
关键词 comparative study German dual system American community colleges Informal education pathways Practice-oriented teaching Policy recommendations
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Comparative Study of the Physicochemical and Microbiological Quality of Water from Wells, Boreholes and Springs Consumed in the Massissia District in Brazzaville, Republic of the Congo
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作者 Martin Tchoumou Raison Félicien Louzayadio Mvouezolo +2 位作者 Harmel Obami-Ondon Lyes Chinalda Boulingui Makaya Adonaï Merci Malera Kombo 《Open Journal of Applied Sciences》 2023年第7期976-986,共11页
The Republic of Congo in the course of the last two decades has been marked by a strong demographic explosion. The increase of its population has been accompanied by a significant demand for drinking water. The Congol... The Republic of Congo in the course of the last two decades has been marked by a strong demographic explosion. The increase of its population has been accompanied by a significant demand for drinking water. The Congolese populations in order to meet their water needs, have recourse to rainwater, surface water and groundwater, because it is easy to access. The city of Brazzaville, political capital of the Republic of Congo, is also affected by this problem. The study carried out here aimed to assess the physicochemical and microbiological parameters of groundwater (wells, boreholes and springs) consumed by the populations of the Massissia district. In this work the physicochemical parameters below were evaluated: the pH, the conductivity, the hardness, the major ions, the undesirable substances as well as some toxic elements (Lead, Cadmium, Iron and Zinc) thanks to techniques of colorimetry, potentiometry and spectrophotometry. The main microbiological parameters determined are E. Coli, Staphylococcus, Total Germs, Total Coliforms, Yeasts and Molds. The physicochemical analyzes revealed that these waters are acidic with pH values between 5 and 6.5, the nitrate concentration evaluated between 50 mg/L and 60 mg/L, and a presence of the element Cadmium at values variants between 0.01 and 0.5 mg/L, values greater than the standard required by the WHO. Microbiological analyzes revealed bacteriological contamination by presence of E. coli in wells and boreholes whose origin is faecal contamination, the presence of yeasts and molds, staphylococcus, Total germs and Total coliforms and Ps Aeuginosis in all water points, making these waters a real danger for consumers. 展开更多
关键词 Water Quality comparative Study Consumption BRAZZAVILLE
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A Comparative Study of Local Legislation on Family Education in China
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作者 Xiaoman Hu 《Journal of Contemporary Educational Research》 2023年第4期85-90,共6页
Since 2017,10 provinces(cities)in China have promulgated local laws and regulations on family education,ushering in ground-breaking improvements in the working mechanism,content,subjects,system,and local characteristi... Since 2017,10 provinces(cities)in China have promulgated local laws and regulations on family education,ushering in ground-breaking improvements in the working mechanism,content,subjects,system,and local characteristics of family education.Based on a comparative study of the local legislation on family education in the 10 provinces,the characteristics and differences are summarized,and recommendations and prospects for local legislation on family education in other provinces are presented in this paper. 展开更多
关键词 Family education Local legislation comparative study
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