bluuebunny/crossref_metadata_2025 huggingface dataset:
ROP examination of premature babies at an eye hospital referred from urban and semi-urban NICUs
Authors: Venkatesh Ramesh , Dave Prachi Abhishek , Gurav Prachi , Agarwal Manisha , Jajoo Mamta , Gupta Vidit
Published: October 2020

Introduction: Retinopathy of prematurity (ROP) is seen in low gestational age (GA) and birth weight (BW) babies leading to retinal vascular damage. Screening of preterm would help in early identification of this, sight-threatening disease. Multiple factors play an important role in planning screening strategies for these preterm. The objective of this study was done to find the differences and the reasons affecting the proportion of ROP distribution between urban and semi-urban regions in North India.

Materials and methods: In this retrospective, comparative study, all babies referred for ROP examination by paediatricians or other general ophthalmologists between 2013 to 2016 were included in the study. Demographic, clinical and treatment related findings were recorded.

Results: Five hundred and fifty eight babies (467: urban and 91: semi urban) were examined for ROP. The mean BW in urban and semi-urban settings was 1348.6 ± 395.21 gm and 1703.77 ± 401.76 gm respectively. The mean GA was 30.99 ± 2.93 weeks and 30.73 ± 2.08 weeks in the urban and semi-urban cohorts respectively. The average time for first ophthalmic examination following birth was 23.82 ± 13.69 (range: 3-77) days in urban and 101.16 ± 238.26 (range: 13- 330) days in semi-urban settings. 94% of the babies completed all screening examination visits. Any ROP was identified in 12% and 33.0% of urban and semi-urban cohorts respectively; Type 1 was detected in 7.5% of urban babies and 24% of semi-urban babies.

Conclusion: Proportion of ROP in the urban region was 3 times lesser than the semiurban region. Differences in proportion of babies developing any ROP and Type 1 ROP between semi-urban and urban groups is likely due to selection bias, as a high proportion of semi-urban babies did not attend for examination or failed to complete all the examinations necessary. This was particularly true for females. More needs to be done to increase access to regular, systematic screening of preterm babies within neonatal units.
Association of Lipid Profile with Severity of Meibomian Gland Dysfunction
Authors: Afroz Irfan Khan Shama , Agrawal Ajai , Singh Anupam , Mittal Sanjeev Kumar , Samanta Ramanuj , . Shrinkhal
Published: October 2020

Introduction: The impact of Meibomian gland dysfunction (MGD) on the overall health of the patient is not known. Efforts are being made to understand the association of dyslipidemia with MGD. The objective of the study was to determine the association of dyslipidemia with the severity of MGD, a contributor to dry eye syndrome.
Materials and methods: We performed an observational case-control study at a tertiary care centre over 18 months and enrolled 116 patients in the age group of 18 to 65 years. A detailed history and clinical examination were done. Following examination, patients were allocated into two groups, patients with MGD and no history of dyslipidemia (cases) and patients without MGD and no history of dyslipidemia (controls). A fasting lipid profile was done for both these groups. The data were subsequently analyzed with SPSS software.
Results: Fifty six (48.3%) of the participants had serum total cholesterol levels ≥200 mg/dl, with a significant association between higher cholesterol levels and severity of MGD (p=0.0001). 77 (66.4%) of the participants had serum triglycerides levels of ≥150 mg/ dl. There was a significant association between the severity of MGD and elevated triglyceride levels (95% confidence interval of Pearson’s chi-square 28.16, p=0.0001). A significant association was also observed between the severity of MGD and elevated LDL levels (95% confidence interval of Pearson’s chi-square 5.95, p=0.015). However, no association was found between HDL levels and the severity of MGD.
Conclusion: The results suggest that patients with MGD and without any history of dyslipidemia, may have higher blood levels of lipid profile components as compared to age-matched controls.
Intensity of reaction to tuberculoprotein is not related to severity of disease in patients with single organ vasculitis of the retina
Authors: Takkar Brijesh , Chauhan Ramesh Chand , Sheemar Abhishek , Rathi Anubha , Sinha Priyanka , Venkatesh Pradeep
Published: October 2020

Not available.
Magnitude and Determinants of Computer Vision Syndrome (CVS) among IT Workers in Kathmandu, Nepal
Authors: Poudel Sudip , Khanal Shankar Prasad
Published: October 2020

Introduction: Computer Vision Syndrome (CVS) is developed among computer workers due to long time working with computers or viewing of the video display terminal (VDT). The objective of this study is to determine the magnitude and determinants of CVS symptoms among IT officers.

Materials and methods: A cross sectional study of IT office workers was conducted at Kathmandu from March to April 2019. Self-administrated questionnaire and observation of researcher was applied to collect information. CVS defect was considered if the participants were having minimum of one symptom during /following use of VDT. The proportion of CVS and its association with different independent factors was carried out.

Results: The prevalence of CVS reported by 263 participants was 82.5% (95% CI: 81.3% - 83.6%), of them 163(62.0%) were not aware about bad effects of computers to the visual apparatus. Goggles were used as protection against CVS by 140(53.2%) participants. CVS symptoms included headache 127(48.0%), tired eyes 123(47.0%) and eye strain 114(43.0%). Use of computer for more than 4.75 hours/day experienced CVS. The mean office work included 7.7 ± 2.02 hours computer work. The video display gadgets usage in home was 2.7 ± 2.35 hours/ day. Not taking breaks (OR:7.3; 95% CI:2.2 - 24.9), not massaging eyes (OR:7.5; 95% CI:1.2 - 47.7), unusual viewing distance (OR:9.0; 95% CI:2.0 - 44.5), improper posture (OR:3.6; 95% CI:1.3 - 10.3), computer usage for more than 10 hours/ day (OR:5.4; 95% CI:1.6 - 18.2) and not aware of CVS (OR:7.2; 95% CI:2.6 - 20.3) were significant predictors of CVS in IT workers.

Conclusion: Most of the IT workers had CVS. Health education and care of IT workers based on predictors found need to be strengthened in the study area.
Artysta — neurobiolog? Malarskie manipulacje procesami widzenia
Authors: Łynnik Maria
Published: October 2020

Art and the notion of beauty related thereto are both disciplines and states which are quite unobvious and thereby requiring us to ask the question: Why is it that human beings have in their minds an inherent need to witness the beauty along with — resultant — need to create and receive art? The author of the text — by devising some neurobiological tools — attempts to elicit relative laws of beauty reception, and simultaneously she utilises the instruments of neuroaesthetics, which is a field of science that investigates the impact of art on processes taking place in the human brain. She explores, among other things, mechanisms put to use, consciously or otherwise, by artists in order to make their works a peculiar stimulus. The author describes a series of “tricks” used by visual arts creators who model the particular ways the visual perception processes function.
Kompetencje kluczowe w edukacji polonistycznej a działalność innowacyjna szkół — przykład rozwiązań dydaktycznych
Authors: Kubarek Marta
Published: October 2020

The aim of the article is to discuss the issue of key competences and to show examples of didactic solutions related to their education in the scope of Polish language education and educational work. The author focuses primarily on social and communication competences. She presents the assumptions of pedagogical innovation, which assumes youth project activities. She also points out the benefits of casting students as explorers, seekers, and creators.
Rozwijanie języka edukacji szkolnej na przykładzie streszczenia
Authors: Szymańska Marta
Published: October 2020

The author of the article defines school communicative situation as the one requiring from the student an ability to use specialised language known as the language of school education. According to regulations currently in force, improving the fluency in the said language is a task of teachers of all school subject because knowing it is one of the conditions of attaining educational success. The article presents a proposal to work on a summary that includes the determinants of school education language.
Aktywizowanie rozwoju sprawności słuchania w języku polskim jako ojczystym
Authors: Chyb Marta Urszula
Published: October 2020

The aim of the present article is to present the typology of listening comprehension skills activated during Polish language lessons. What the author claims is that in Polish school two types of listening co-exist, namely: natural and activated. The former resembles conditions of natural communication, since a student assumes the role of text recipient, whereas the latter is a process of teaching the skills of listening comprehension. Based on questions and instructions elicited from selected school handbooks shows in what way the activated type of listening comprehension is taught as a part of Polish as a mother tongue lessons.
ТЕОРЕТИКО-КОНЦЕПТУАЛЬНА СУТНІСТЬ СТРАТЕГІЇ ТА СТРАТЕГІЧНОГО УПРАВЛІННЯ БІЗНЕСОМ В УМОВАХ СУЧАСНОЇ ЕКОНОМІКИ
Authors: Перит Ірина Олегівна
Published: October 2020

The purpose of the scientific research is to study the theoretical and conceptual aspect of strategy and strategic management in the operation of private business, and develop recommendations on their actual interpretation in the modern economy. The methodological aspect of the work is formed by theoretical conclusions and generalizations of the economic science and scientific works on the basis of strategy and strategic management in the operation of private business. The work applies logical, comparative and complex approaches as well as empirical research, comparison and complex analysis methods.During the research, significant scientific developments regarding the core of strategy and strategic management were analyzed and structured. The aspects of the main structural elements of the strategy were described: policy, tactics, management procedures, planning and budgeting. The essence of the subject (solutions), which are recommended for creating effective business management strategies, is proposed. Scientific approaches to understanding the core of strategic management are studied.On the basis of the conducted research, scientific approaches to strategy and strategic management are offered to group on the basis of complexity and the consideration of aspects of enterprise activity on: point approaches, approaches of relativity, panoramic approaches. The author's definition of the concept of "strategy" and "strategic management" is presented and the attention is focused on their short-, medium- and long-term perspective.The scientific value of the research results lies on their focus on solving the problem of searching for the concepts of an effective strategy and strategic business management, which can ensure the competitiveness and improvement of the financial results of the private sector, as well as the growth of the national economy.
Prevalence and Associated Factors of Diabetic Foot at Risk among Type 2 Diabetes Mellitus Patients Attending Primary Health Clinics in Kuantan
Authors: Azmi NH , Abdul Hadi A , Md Aris MA , Nasreen HE , Che-Ahmad A
Published: October 2020

Introduction: The diabetic foot at risk is the diabetic foot which is at risk of ulceration, hence the importance of identifying the foot at this stage. This study aims to assess the prevalence of diabetic foot at risk and its associated factors among type 2 diabetes mellitus patients’ attending primary health clinics in Kuantan. Methods and methods : This was a cross-sectional study conducted at four primary health clinics in Kuantan involving 450 study participants who were selected by using universal sampling method. Foot examination was carried out and foot at risk was classified based on the Kings’ Classification. Multiple logistic regressions were performed to identify the predictors for diabetic foot at risk. Results: The prevalence of diabetic foot at risk was 31.3%. Multivariate logistic regression analysis identified age (OR 1.04, 95% CI: 1.01-1.06), smoker (OR 4.11, 95% CI: 1.96-8.63) and duration of diabetes more than 10 years (OR1.77, 95% CI: 1.05-2.98) as risk factors for diabetic foot at risk. Respondents with higher diabetic foot practice score (OR 0.87, 95% CI: 0.77-0.98) have lesser risk of developing diabetic foot at risk. Conclusion: Patients who are older, smoker and/or have chronic diabetes are predicted to be at higher risk to develop the diabetic foot at risk. This study also showed that patients with better foot care practice has lesser risk. Therefore, these are the groups of patients that need to be targeted for early detection and intervention to prevent serious complications.
Diagnostic Accuracy of Intraoperative Frozen Sections in the Diagnosis of Central Nervous System Lesions: A Hospital-Based Study
Authors: Win TT , Tuan Sharif SE , Mat Zin AA
Published: October 2020

Introduction: Intraoperative frozen section (FS) is an important tool in the management of neoplastic and non-neoplastic central nervous system (CNS) lesions. Although the final pathological diagnosis is based on the findings in paraffin tissue sessions, interpreting FS of CNS lesion is to assist the neurosurgeon in making the accurate judgment regarding the nature of the lesion and tissue adequacy. This study was to evaluate the agreement between FS and paraffin sections (PS) results; and to highlight the possible causes of error in discrepancy between FS and PS. Materials & Methods: This is a retrospective study of 85 cases of FS. H&E stained sections of both FS and PS of all these cases were reviewed with their histopathological reports. FS and PS results were compared. Possible causes of errors were reviewed and recorded. Results: Out of 85 cases; 76 cases (89.4%) showed no discrepancy, 2 cases (2.4%) minor discrepancy and 7 cases (8.2%) discrepancy. Sensitivity and specificity of FS were 90.1% and 85.7% respectively. Positive predictive value was 97.0% and negative predictive value was 63.1%. The false positive rate was 14.2% and false negative rate was 36.8%. The overall accuracy of FS was 89.4%. Conclusion: Our results showed high accuracy and specificity of FS. Therefore, FS is still useful, an effective tool for neurosurgeon although there are some challenges for histopathologists in reporting FS. The commonest discrepancy was seen between reactive gliosis and low-grade glioma. Over-diagnosis or under-diagnosis of FS can be reduced by closed cooperation among pathologist, neurosurgeon and radiologist.
Does Dietary Adequacy Reflect the Cognitive Performance of Children? A Study among the Homeless Children in Klang Valley, Malaysia
Authors: Chin K.J. , A Asma' , Yusof HM , Churak P. , K Latiffah
Published: October 2020

Introduction: Homeless children are prone to inadequate energy and nutrient intake which may highly influence their cognitive performance. However, few studies have been done in assessing diet adequacy and cognitive performance among homeless children in Malaysia. Materials and Methods: This cross-sectional study aims to assess the dietary adequacy and cognitive performance of 120 homeless children age 7-12 years living in Klang Valley. The dietary adequacy of these homeless children was assessed through two days of 24 hours of dietary recall. Dietary adequacy achievement was determined by fulfilling at least 50% of Recommended Nutrients Intake (RNI). Raven’s Coloured Progressive Matrices (RCPM) test was used to assess their cognitive performance. Results: The homeless children had an adequate intake of energy, iron, zinc, and vitamin B12. Seventy percent of homeless children had a poor cognitive performance. This study shows that there was no association between energy, iron, and vitamin B12 adequacy with cognitive performance, whereas there was a significant (p=0.028) association between zinc adequacy and children’s cognitive performance. Conclusion: These findings provide solid evidence-based for dietary adequacy and cognitive performance of the homeless children in Klang Valley. It is clear from the findings that both dietary intake and cognitive of these children require improvement for a better quality of life in the future. This study suggests that dietary adequacy does not relatively reflect the cognitive performance of these homeless children in Malaysia.
Male Infertility: Evaluation and Treatment
Authors: Hamad Mohamed ZB , Hamad Alfarisi HA , Abdul Wahab AY , Abd Fuaat A , Che Mohamad CA , Ibrahim M
Published: October 2020

Globally, 48.5 million couples are suffering from infertility. One of six couples in United Kingdom is categorized as infertile. In developing countries, infertility affects one of four couples. Male infertility constitutes about 40-50% of the incidence. A minimum of 30 million men worldwide are infertile. Mortality rate is higher in men with impaired semen quality than those who have normal semen quality. The initial evaluation of a male partner of an infertile couple should be done if there is a delay in the pregnancy in the female partner for one year or more from unprotected sexual intercourse. It can be done earlier if there is a predisposing factor for infertility. Identification of the underlying aetiology of infertility is the guide for treatment course which could be medical, surgical or through assisted reproductive technology. The aim of this review is to highligh the main courses of evaluation and treatment of male infertility.
Uma análise construcional das formações lexicais baseadas em coronavírus no português brasileiro contemporâneo
Authors: Gonçalves Carlos Alexandre
Published: October 2020

Neste texto, analisamos a formação técnica coronavírus, desde a criação em sua área de especialidade (a infectologia) até os dias de hoje. Observando os aspectos morfológicos e semânticos envolvidos nos processos de formação de palavras utilizados, pretendemos mapear as estratégias de que se vale o falante para expressar ponto de vista com construções lexicais, representando, nos moldes de Booij (2010), os esquemas e subesquemas utilizados. Nessa empreitada, a principal fonte de dados foi a Internet, sobretudo as redes sociais: Twitter, Instagram e Facebook.
Estudo diacrônico da ordenação das construções causais com porque e por+infinitivo sob a perspectiva de princípios funcionais
Authors: Floret Mayra França , Paiva Maria da Conceição Auxiliadora de
Published: October 2020

As construções causais conectadas por porque e por+infinitivo compartilham diversas semelhanças. Dentre elas, destaca-se a flexibilidade de posição da oração causal, que pode ser anteposta, posposta ou interposta à oração efeito. Neste artigo, investigamos a relação entre essas diferentes possibilidades de organização e princípios funcionais mais gerais, quais sejam, iconicidade e distribuição de informação, nos períodos clássico e moderno do português. O objetivo central é discutir possíveis mudanças na organização sintagmática dessas construções, motivadas pela própria representação da relação causal, que pressupõe que causas precedem seus efeitos e pelo princípio discursivo de que informação velha precede informação nova. Para tanto, analisamos uma amostra de textos não literários produzidos entre os séculos XVII e XX/XXI. Através de uma análise quantitativa, mostramos que, contrariando as expectativas, tanto as orações causais com porque como as com por+infinitivo são predominantemente pospostas à oração efeito no intervalo de tempo considerado, independentemente do seu estatuto informacional e da sequencialidade entre os estados de coisas codificados, indicando a fixação de uma ordem default.
Das páginas às telas: uma abordagem multi-dimensional da adaptação da linguagem da literatura young adult para o cinema
Authors: Veirano Pinto Marcia , Valente Tiago Marcondes
Published: October 2020

Obras cinematográficas como The outsiders (1983), The basketball diaries (1995) e Harry Potter and the sorcerer´s stone (2001) são exemplos do número crescente de adaptações dos romances categorizados como young adult, ou “jovem adulto”, produzidos nas últimas décadas e direcionados a um público de idade superior ao infantil e inferior ao público adulto. O objetivo de nossa pesquisa é compreender de que forma a linguagem verbal presente nos livros young adult é adaptada para a linguagem audiovisual do cinema. Para tal análise, partimos da coleta de textos para formação do Young Adult Corpus, que incluiu o texto de 30 obras literárias e 30 legendas de filmes cujos enredos são adaptações desses romances. O estudo de variação entre os traços linguísticos dos diferentes tipos de linguagem foi feito por meio de uma análise multi-dimensional aditiva, embasada nas dimensões de variação do inglês (Biber, 1988). Os resultados mostram que, ao saírem das páginas para as telas, as histórias ficam mais interativas, menos narrativas e mais dependentes de contexto.
Interview with Florent Perek
Authors: Machado Vieira Marcia Dos Santos , Freitas Junior Roberto De , Alonso Karen Sampaio Braga
Published: October 2020

Professor Florent Perek has a PhD in English and General Linguistics (University of Freiburg) and is a Lecturer in Cognitive Linguistics at the Department of English Language and Applied Linguistics at University of Birmingham, UK. Professor Perek is the author of several articles in international peer-reviewed journals and has, among his most important publications, the 2015 book, Argument structure in usage-based construction grammar: experimental and corpus-based perspectives, edited by John Benjamins.------------------------------------------------------------------------------------ENTREVISTA COM FLORENT PEREKFlorent Perek é Doutor em Inglês e Linguística Geral (Universidade de Freiburg, Alemanha) e Professor da área de Linguística Cognitiva do Departamento de Língua Inglesa e Linguística Aplicada na Universidade de Birmingham, no Reino Unido. Perek é autor de uma série de artigos em revistas renomadas internacionalmente e tem, entre suas importantes publicações, seu livro de 2015, o qual foi intitulado Estrutura argumental na gramática de construções baseada no uso: perspectivas experimental e baseada em corpus e foi editado pela John Benjamins.---Original em inglês.
Artificial neural networks modelling for biodiesel production from waste cooking oil
Authors: KARACAN Suleyman , GEDİKASLAN Büşra , ÇAĞATAY Mehmet
Published: October 2020

The objective of the present work is to develop models inculcating the effect of operating conditions of waste cooking oil methyl esters production in the reactive distillation column, namely waste cooking oil (WCO) flow rate, methanol/WCO molar ratio, reboiler heat duty and feed inlet temperature on the estimation of parameters like the biodiesel conversion by using Artificial Neural Networks technique. In our study, at the maximum biodiesel conversion of 99.48% and at steady state time of 1.69 hour were determined as WCO flow rate of 2.90 ml/min, methanol/oil molar ratio of 8.19 and reboiler heat duty of 0.419 kW. Experiments were conducted in the laboratory and the results obtained were used to develop the ANN model using MATLAB. The developed model was in good agreement with the experimental values.
Barriers and Cultural Issues of Land Transaction
Authors: Bano Shumaila , Chaudhry Abid Ghafoor
Published: October 2020

Land is an important part of nature. In Pakistan the main issue is the transaction of land. The researchers heed rare attention towards this sensitive issue. This issue of land has always been considered. alarming for the people of Pakistan. The distribution of property is playing a pivotal role to strengthen and weaken the relationships since long. The lands devoured the old, loved and precious relationships in a moment. The property has been the root of dispute which compelled.a son to fight with his father and a brother with. brother. Land administration systems are established to eliminate these issues, ...for the native people of Muzaffargarh. A reasonable number of respondents were selected from Muzaffargarh by using the technique of random sampling. Case study method was helpful to contract intensive data.. Other themes were fares allocated by the government for reducing poverty. Related revenue office could play an integral role in land transaction to reduce their land problems.
Critical Analysis of Social Constructivism: Myth or Reality for Peace and Security
Authors: Rahim Nazim , Ali Asghar
Published: October 2020

Subjectivity is the mother of all social sciences. There is no universal truth, there is no objective reality and there is no finality in social sciences. Final truth belongs to heaven, not to this world and none of the theories can claim finality or objectivity. Nonetheless, theories try to explain the truth, holding water, either more or less. Theories, highlighting the intrinsic nature of humans [good & bad], the structure of international system (anarchic)or class struggle[bourgeois & proletariat]are both researchable and discernible. Social Constructivism, on the other hand labels all the theories as social constructions and itself constructs an endless desert of ideas, develops absurdity, and makes the truth less accessible and more mythical. Social Constructivism, instead of explaining the truth is making it blurred and doubtful. Instead of ensuring clarity, its own assumptions are constructing a mythical world. This analytical paper critically analyzes the social constructivists' assumptions and their critique on all the established beliefs in general and mainstream perspectives in particular.
Numerical studies on residual strength of dented tension leg platforms under compressive load
Authors: Do Quang Thang , Huynh Van Nhu , Tran Dinh Tu
Published: October 2020

This paper focuses on numerical investigations and derived formulation to evaluate the residual strength of tension leg platforms (TLPs) with the local denting damage under axial compression loading. The damage generation scenarios in this research are represented the collision accidents of offshore stiffened cylinders TLPs with supply ships or floating subjects. The finite element model is performed using a commercial software package ABAQUS, which has been validated against the experiments from the authors and other researchers. Case studies are then performed on design examples of LTPs when considering both intact and damaged conditions. Based on the rigorous numerical results, the new simple design formulations to predict residual strength of dented TLPs are derived through a regression study as the function of a non-dimensional dent depth. The accuracy and reliability of the derived formulation are validated by comparing it with the available test results in the literature. A good agreement with existing test data for ship-offshore structure collisions is achieved.

Keywords:

dented stringer-stiffened cylinder; residual strength; tension leg platforms (LTPs); axial compression; residual strength formulation.
Failure probability analysis of overhead crane bridge girders within uncertain design parameters
Authors: Hai Trinh Van , Thu Nguyen Huu , Tuan Ha Dang , Hiu Pham Van
Published: October 2020

In the design of steel crane girders, various sources of uncertainty such as material properties, loads, and geometric tolerances are inherent and inevitable. Using deterministic structural and/or load conditions may lead to low-reliability systems in real applications. In this paper, the probability of failure of overhead crane bridge girders with uncertain design parameters is investigated. First, the design problem of a crane double girder is introduced within a set of analytical stress and defection constraints. Then, the response surface method is used in conjunction with Monte Carlo methods to quantify the effect of the parameter uncertainties on the constraints of stress and deflection. For illustrative examples, various configurations of girders with original deterministic parameters proposed in the literature are selected and their deterministic optimization values are considered as the mean of random variables. The obtained results reveal that uncertainties such as coefficients of variation (COV) in structures and loads have strong effects on the probability of failure for all stated crane girder configurations. For only a wheel load COV of 0.05 and geometric dimension COV of 0.025, the means of geometric parameters have to be larger than 1.1 their deterministic-based values in order to reach a probability of failure at a level of 10-4.

Keywords:

failure probability; double-box girder; overhead crane; Monte Carlo method.
Phương pháp gần đúng xác định diện tích mặt tiếp xúc của gối cách chấn đàn hồi cốt sợi không liên kết hình khối hộp với các bệ đỡ
Authors: Hùng Trương Việt , Thuyết Ngô Văn
Published: October 2020

Gối cách chấn đàn hồi cốt sợi không liên kết (gối U-FREI) là một loại gối cách chấn đàn hồi tương đối mới. Gối có cấu tạo gồm các lớp cao su xen kẹp và gắn kết với các lớp sợi mỏng. Gối U-FREI được đặt trực tiếp lên trên bên trên phần đài móng và dưới phần thân công trình mà không cần bất kỳ một liên kết nào giữa chúng. Biến dạng cuộn là một đặc trưng cơ bản của gối U-FREI khi chịu chuyển vị ngang. Nó thể hiện sự không liên kết giữa lớp cao su ngoài cùng của gối U-FREI với các mặt bệ đỡ (phần móng và phần thân công trình). Diện tích mặt tiếp xúc giữa các mặt của lớp cao su ngoài cùng của gối U-FREI với các bệ đỡ có ảnh hưởng lớn đến ứng xử ngang của gối U-FREI. Trong nghiên cứu này, diện tích mặt tiếp xúc của gối U-FREI hình khối hộp với các bệ đỡ được xác định bằng phương pháp tính toán gần đúng.

Từ khóa:

gối cách chấn; gối cách chấn đàn hồi cốt sợi không liên kết; biến dạng cuộn; diện tích ngang hiệu dụng; mặt tiếp xúc.
Ảnh hưởng của độ rỗng vi mô đến hệ số khuếch tán ion clo hữu hiệu của đá xi măng
Authors: Hải Nguyễn Đình , Tuấn Trần Anh , Dũng Nguyễn Tiến
Published: October 2020

Bài báo này được thực hiện với mục đích nghiên cứu ảnh hưởng của độ rỗng vi mô (độ rỗng hình thành bởi lỗ rỗng mao dẫn và lỗ rỗng khí kích thước µm) đến khả năng khuếch tán ion clo của đá xi măng. Để dự đoán hệ số khuếch tán ion clo hữu hiệu, đá xi măng có thể được mô phỏng bởi các phương pháp đồng nhất hoá cơ học vi mô dựa trên nghiệm của bài toán Eshelby coi đá xi măng bao gồm các pha hạt hình cầu không khuếch tán được phân bố trong các pha nền có khả năng khuếch tán. Kết quả của bài toán mô phỏng là hệ số khuếch tán hữu hiệu của đá xi măng là một hàm phụ thuộc vào tỷ lệ thể tích của vi lỗ rỗng và hệ số khuếch tán trong dung dịch lỗ rỗng. Các kết quả giải tích thu được sẽ được so sánh với các kết quả thực nghiệm đã được thực hiện trong các công bố trước đây.

Từ khóa:

hệ số khuếch tán ion clo hữu hiệu; đá xi măng; đồng nhất hoá cơ học vi mô; nghiệm bài toán Eshelby; vi lỗ rỗng.
Lựa chọn phương pháp điều khiển sức cản thủy lực trong hệ thống thủy lực trên cơ cấu lắp dựng cần trục tháp
Authors: Giang Dương Trường
Published: October 2020

Trong quá trình lắp dựng cần trục tháp tiềm ẩn rất nhiều yếu tố có thể gây mất an toàn lao động, đặc biệt liên quan tới việc điều khiển hệ thống thủy lực của cơ cấu lắp dựng khi giữ tải và hạ tải trọng. Chính vì vậy việc lựa chọn phương pháp và chế độ điều khiển hệ thống thủy lực này phải được xem xét cẩn thận trong quá trình thiết kế. Bài báo giới thiệu và phân tích đặc điểm làm việc của các hệ thống thủy lực của cơ cấu lắp dựng cần trục tháp. Sau đó thiết lập cơ sở lý thuyết xác định chế độ điều khiển và phối hợp các sức cản thủy lực theo nguồn áp suất, vận tốc hạ tải trọng. Cuối cùng kết quả nghiên cứu của bài báo được thảo luận và đánh giá qua ví dụ thử nghiệm số. Kết quả của bài báo đã xây dựng được các công thức bằng giải tích để tính toán hệ số điều chỉnh giữa hai sức cản thủy lực trong việc lựa chọn phương pháp và chế độ điều chỉnh hệ thống dựa trên mô hình tính toán tổng quát. Nghiên cứu này áp dụng cho việc thiết kế cơ cấu lắp dựng cần trục tháp và các thiết bị nâng tương tự trong.

Từ khóa:

van áp suất; van tiết lưu; điều khiển vận tốc; cần trục tháp; hệ thống thủy lực.
Lựa chọn nhà cung cấp vật liệu cho nhà thầu xây dựng bằng phương pháp AHP
Authors: Toản Nguyễn Quốc , Hạnh Nguyễn Thị Mỹ
Published: October 2020

Lựa chọn nhà cung cấp vật liệu là hoạt động quan trọng góp phần đảm bảo chất lượng, tiến độ của dự án và lợi nhuận của nhà thầu xây dựng. Trên cơ sở so sánh các phương pháp đánh giá lựa chọn đa mục tiêu trong đánh giá lựa chọn nhà cung cấp, bài báo đề xuất áp dụng phương pháp AHP để lựa chọn nhà cung cấp vật liệu. Tiêu chí lựa chọn nhà cung cấp vật liệu xây dựng cho nhà thầu tại Việt Nam thông qua khảo sát phỏng vấn chuyên gia. Kết quả của nghiên cứu cho thấy có 8 tiêu chí chính quan trọng trong việc lựa chọn nhà cung cấp vật liệu cho nhà thầu xây dựng Việt Nam bao gồm: Giá cả; thời gian giao hàng; chất lượng sản phẩm; chất lượng dịch vụ, bảo hành; khả năng đáp ứng nguồn hàng; năng lực của nhà cung cấp; tỷ lệ hàng hư hỏng và chính sách thanh toán. Thông qua ví dụ cụ thể cho bài toán lựa chọn nhà cung cấp thép cho công trường xây dựng bằng phương pháp AHP. Kết quả nghiên cứu đóng góp quan trọng cả về phương diện khoa học và thực tiễn trong hoạt động lựa chọn nhà cung cấp vật liệu nói riêng và hiệu quả hoạt động sản xuất kinh doanh của nhà thầu xây dựng nói chung.

Từ khóa:

nhà cung cấp vật liệu; AHP; tiêu chí; nhà thầu thi công.
Phân tích tĩnh dầm composite sử dụng lý thuyết biến dạng cắt bậc cao hai biến
Authors: Nhân Nguyễn Thiện , Dương Nguyễn Ngọc , Kiên Nguyễn Trung
Published: October 2020

Bài báo này đề xuất một lý thuyết biến dạng cắt bậc cao hai biến để phân tích ứng xử tĩnh của dầm composite. Trường chuyển vị của bài toán được rút gọn từ lý thuyết biến dạng cắt bậc cao ba biến bằng cách sử dụng phương trình cân bằng tĩnh học. Phương trình chủ đạo được thành lập từ phương trình Lagrange. Lời giải Ritz, với hàm xấp xỉ là hàm số mũ cơ số Napier, phù hợp với các điều kiện biên khác nhau được đề xuất để giải bài toán. Sự hiệu quả của trường chuyển vị đề xuất và hàm xấp xỉ Ritz mới được phân tích, đánh giá. Các ví dụ số được thực hiện để khảo sát độ hội tụ của lời giải và so sánh với các nghiên cứu trước. Ảnh hưởng của điều kiện biên, hướng sợi, tỷ số chiều dài/chiều cao dầm, đặc biệt là biến dạng cắt đến chuyển vị và ứng suất của dầm composite lớp được khảo sát và bình luận chi tiết.

Từ khóa:

dầm composite; lý thuyết biến dạng cắt bậc cao; phương pháp Ritz; phân tích tĩnh; rút gọn trường chuyển vị.
Đề xuất quy tắc tạo lập mô hình BIM phục vụ việc tự động hóa đo bóc khối lượng trong các dự án xây dựng sử dụng vốn nhà nước tại Việt Nam
Authors: Phương Lưu Quang , Quân Nguyễn Thế
Published: October 2020

Mô hình thông tin công trình (Building Information Modeling, viết tắt là BIM), một xu thế mới cho ngành xây dựng hiện nay, khi được ứng dụng trong các dự án đầu tư xây dựng đã cho thấy những ưu điểm vượt trội trong việc kết xuất khối lượng tự động. Tuy nhiên, tại Việt Nam, do người dựng mô hình ban đầu thường là các họa viên, kỹ sư, kiến trúc sư, kiến thức chuyên sâu về dự toán không phải là thế mạnh của họ, vì vậy họ quan tâm chủ yếu đến hình khối kết cấu, kiến trúc v.v. mà chưa quan tâm đến các thông tin phục vụ đo bóc khối lượng và lập dự toán. Do đó, mô hình BIM được họ dựng lên khi sử dụng để xuất khối lượng cho kết quả khối lượng chưa phù hợp với yêu cầu bóc tách khối lượng từ các hướng dẫn, quy định về đo bóc khối lượng hiện nay, cần được điều chỉnh thủ công, dẫn đến giảm độ chính xác và năng suất bóc tách, mà các công cụ hỗ trợ dựng mô hình và bóc khối lượng từ mô hình BIM phổ biến hiện nay chưa giải quyết được vấn đề này. Bài báo đề xuất một số quy tắc cần tuân thủ khi tạo lập mô hình BIM dành cho người dựng mô hình, để giảm nhẹ khối lượng điều chỉnh mô hình, bổ sung thông tin sau này cho người bóc tách khối lượng. Các quy tắc này không quá phức tạp để làm giảm năng suất và hiệu quả của những người dựng mô hình ban đầu, nhưng vẫn đảm bảo giảm được đáng kể khối lượng xử lý, điều chỉnh mô hình cho người bóc tách khối lượng, từ đó tăng được tốc độ và hiệu quả chung khi áp dụng BIM trong dự án đầu tư xây dựng tại Việt Nam.

Từ khóa:

dự án sử dụng vốn nhà nước; mô hình thông tin công trình; đo bóc khối lượng; đối tượng BIM.
Peningkatan Kapasitas Forum Anak Tangsel Mengenai Pembangunan Kota dan Komunitas Berkelanjutan
Authors: Hikmawan Rizky , Maulida Rizkiya Ayu
Published: October 2020

The aim of the eleventh goal of Sustainable Development Goals (SDGs) is to create a livable city for its citizens. Therefore, this goal also intended to eliminate the problems faced by the city, such as: traffic, slum area, and the potential for natural or human made disaster. The Government of Tangsel must always prepare themselves to resolve all the problems to create a livable city. However, the responsibility for resolving existing problems does not only lie with the Government of Tangsel. The citizens are also demanded to be able to contribute to the sustainable development of the city and its communities. One of the communities in this city is Forum Anak Tangsel (Fatangsel). Therefore, we would like to facilitate a capacity building for Fatangsel to realizing their participation in developing their city and its communities through the perspective of SDGs.
Peningkatan Pemahaman Remaja Tentang Bakteri Ropionibacterium Acnes Bagi Kesehatan Kulit
Authors: Rindi Novitri Antika
Published: October 2020

This dedication activity aims to increase the knowledge of adolescents about Propionibacterium acnes bacteria for skin health, especially acne, and form the awareness of adolescents to maintain and enhance the level of personal health. The specific target is for teenagers to be aware of how to maintain healthy skin, especially the face, remembering that adolescence is a period where their activities are very high, like activities outside the home, often forgetting to clean faces exposed to dust and dirt, as well as hormonal changes that affect the physiological of the body. This activity also provides knowledge about the bacteria Propionibacterium acnes, ranging from understanding, characteristics to the mechanism of action of bacteria. The methods and techniques of socialization consist of stages: planning, action, and reflection. 1) planning is carried out with the preparation and socialization of the program; 2) action, i.e. the implementation phase of the service, begins with exposure to the bacterium Propionibacterium acnes, the mechanism of action of the bacteria and its relation to skin health, then proceed with a question and answer session; 3) reflection, done by analyzing the participants' responses to the activities that have been carried out.
Program Pengembangan Usaha Produk Intelektual Kampus “Kantor Konsultan Bisnis, Akuntansi dan Pajak”
Authors: Fadrul Fadrul , Sarli Rahman  , Sudarno  , Yusrizal
Published: October 2020

Every college must have a business unit that is able to seek funding apart from students. One of the universities that has a business unit is the Institut Bisnis dan Teknologi Pelita Indonesia. The business unit that is carried out is the Business, Accounting and Tax Consultant Office with services offered namely business consulting, accounting and finance and taxation. Some of the clients that have been handled by the consultant team are Raso Stiujuah Restaurant and BUMDes Sialang Kubang. The method used is that the consultant team looks for the root of every problem faced by the client, then provides the best solution for the client. For Raso Situjuah Restaurant, to survive the changing business world situation and the current pandemic atmosphere is to create frozen products and with a digital-based marketing system. Meanwhile, for BUMDes Sialang Kubang, in managing the BUMDes, personal and institutional strengthening is needed in the form of Standard Operational Procedures (SOP) and the availability of an accurate and accountable information system.
A Relational View of Pastoral (im)mobilities
Authors: Maru Natasha
Published: October 2020

Pitched against the apparently more civilised and modern ‘settled’ folk, pastoralists have historically been penalised for the seemingly primitive and outdated practice of mobility. Drawing on ethnographic fieldwork in western India, this article challenges this reductive dichotomy and unpacks the many (im)mobilities produced, accessed, experienced and imagined by pastoralists. Adopting a relational lens, it shows how mobilities and immobilities co-constitute and are contingent on each other across social, geographical and temporal scales. Embedded within their own social and political history, the many forms of (im)mobilities can not only ontologically dispel the homogenizing effects of rigid typologies, but also but also practically offer pastoralists the capacity to adapt to changing times.
Does Mild Traumatic Brain Injury Increase the Risk for Dementia? A Systematic Review and Meta-Analysis
Authors: Snowden Taylor M. , Hinde Anthony K. , Reid Hannah M.O. , Christie Brian R.
Published: October 2020

Background: Mild traumatic brain injury (mTBI) is a putative risk factor for dementia; however, despite having apparent face validity, the evidence supporting this hypothesis remains inconclusive. Understanding the role of mTBI as a risk factor is becoming increasingly important given the high prevalence of mTBI, and the increasing societal burden of dementia. Objective: Our objective was to use the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) format to determine if an association exists between mTBI and dementia and related factors, and to quantify the degree of risk. Methods: In this format, two authors conducted independent database searches of PubMed, PsycInfo, and CINAHL using three search blocks to find relevant papers published between 2000 and 2020. Relevant studies were selected using pre-defined inclusion/exclusion criteria, and bias scoring was performed independently by the two authors before a subset of studies was selected for meta-analysis. Twenty-one studies met the inclusion criteria for this systematic review. Results: The meta-analysis yielded a pooled odds ratio of 1.96 (95% CI 1.698–2.263), meaning individuals were 1.96 times more likely to be diagnosed with dementia if they had a prior mTBI. Most studies examining neuropsychiatric and neuroimaging correlates of dementia found subtle, persistent changes after mTBI. Conclusion: These results indicate that mTBI is a risk factor for the development of dementia and causes subtle changes in performance on neuropsychiatric testing and brain structure in some patients.
Burnout of Healthcare Workers in Acute Care Geriatric Facilities During the COVID-19 Crisis: An Online-Based Study
Authors: El Haj Mohamad , Allain Philippe , Annweiler Cédric , Boutoleau-Bretonnière Claire , Chapelet Guillaume , Gallouj Karim , Kapogiannis Dimitrios , Roche Jean , Boudoukha Abdel Halim
Published: October 2020

Background/Objective: The COVID-19 crisis has been increasing the burden of healthcare workers in acute care geriatric facilities. These workers have been dealing with drastic changes in the care they provide to their residents including cancelation of group activities and communal dining and even restrictions of activities outside rooms. Healthcare workers have also been devoting more time and energy to perform COVID-related medical duties. Geriatric facilities have been facing shortages in equipment and supplies, as well as staffing shortages. Finally, healthcare workers have been facing challenges regarding their personal safety and that of their families. Consequently, we hypothesized the presence of high levels of burnout among healthcare workers during the COVID-19 crisis. Methods: To evaluate burnout in healthcare workers in French acute care geriatric facilities, we used an online survey based on the Oldenburg Burnout Inventory. Eighty-four healthcare workers answered the survey, during April of 2020. Results: Analysis demonstrated that they were experiencing medium levels of burnout, exhaustion, and disengagement. Conclusion: This level of burnout reflected their fatigue, loss of energy, and/or feelings of being overextended and exhausted. Considering the expected cumulative impact of various stressors, the medium level of burnout observed has come as a surprise to us and might actually be considered as relatively good news. Nevertheless, no level of burnout is negligible and has wide ranging negative consequences.
Controllable electromagnetic negative stiffness spring for vibration isolator: Design, analyses and experimental verification
Authors: Meng Kai , Gu Yong , Ma Jianhui , Liu Xidong , Geng Xiangqian , Liu Yuxi , Liu Xuhe , Zhang Haoming , Shao Fengxiang
Published: October 2020

In this study, a novel negative stiffness spring is developed. The developed spring possesses the characteristics of the controllable stiffness and can be employed in vibration isolation system with a low resonance frequency. The controllable electromagnetic negative stiffness spring (CENSS) is obtained by the coaxial permanent magnets (PMs) and the circular current-carrying coils. The stiffness control is accomplished by changing the current in the coils. Furthermore, the mathematical model of CENSS is established, based on the filament method. According to the model, the relationship between the exciting current and the axial stiffness is obtained. Moreover, the influence of the structural parameters of CENSS on the magnetic force and the stiffness is analyzed. The results demonstrate that the thickness of PMs and the coils have the ability to adjust the range of the negative stiffness. Finally, performance experimental study of CENSS in the stiffness domain is carried out under different exciting currents and thicknesses. The experimental results have shown a good agreement with the model. It demonstrates that the performance of negative stiffness in CENSS can be controlled efficiently by the exciting current and optimized by the thickness.
Analysis of Lift-Off Effect on Transmitter-Receiver Probe in Eddy Current Testing
Authors: Zhang Qing , Li Xin , Tian Guiyun
Published: October 2020

The Transmitter-Receiver Probe (TR probe), which has improved signal-to-noise ratio, deep penetration depth, and directional measurement is used in pulsed eddy current testing (PECT). Whereas, the lift-off effect on the TR probe is one of the main obstacles. The purpose of this paper is to analyze the lift-off effects on the TR probe and presents a feature for lift-off estimation. Firstly, an analytical model of a TR probe is given based on previous studies. Secondly, on the basics of the analytical model, the spectrum of the PECT signal is studied, and the lift-off effects on the TR probe are analyzed. Then, the lift-off effects under different coil distances are studied and a D Intersect Point (DIP) is proposed for the lift-off estimation. Results show that the TR probe can be used to reduce the lift-off effect for the non-ferromagnetic materials and the ferromagnetic materials. And both the DIP time and amplitude can be used for lift-off estimation. However, the DIP time is better, as its evolution curve with lift-off is a straight line with the same slope. The study is believed to be helpful for the TR probe design, the lift-off measurement, and the thickness assessment and defect quantification.