• 대한수학회논문집
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• 제34권1호
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• pp.55-82
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• 2019

Given ${\sigma}:G{\rightarrow}G$ an involutive automorphism of a semigroup G, we study the solutions and stability of the following functional equations $$f(x{\sigma}(y))=f(x)g(y)+g(x)f(y),\;x,y{\in}G,\\f(x{\sigma}(y))=f(x)f(y)-g(x)g(y),\;x,y{\in}G$$ and $$f(x{\sigma}(y))=f(x)g(y)-g(x)f(y),\;x,y{\in}G$$, from the theory of trigonometric functional equations. (1) We determine the solutions when G is a semigroup generated by its squares. (2) We obtain the stability results for these equations, when G is an amenable group.

• Wind and Structures
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• 제29권2호
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• pp.129-137
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• 2019

The maximum along-wind displacement of a considerable amount of building under simulated wind loads is computed with the aim to produce a simple prediction model using multiple regression analysis with variables transformation. The Shinozuka and Newmark methods are used to simulate the turbulent wind and to calculate the dynamic response, respectively. In order to evaluate the prediction performance of the regression model with longer degree of determination, two complex structural models were analyzed dynamically. In addition, the prediction model proposed is used to estimate and compare the maximum response of two test buildings studied with wind loads by other authors. Finally, it was proved that the prediction model is reliable to estimate the maximum displacements of structures subjected to the wind loads.

• Journal of Smart Tourism
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• 제1권3호
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• pp.17-20
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• 2021

Technology and tourism have become inseparable, and technological innovations propose new services to the tourism industry. During the current pandemic, service robot usage has increased more than at any other time which comes with advantages and disadvantages. This paper discusses the opportunities and challenges of utilizing service robots in the service industry during and after the pandemic crisis. The study follows a content analysis methodology. Findings indicate that service robots are easy to access, offer an alternative form of communication, reduce costs and boost operational safety; in contrast, robotics increase unemployment and cause anxiety and depression among the demoralized employees.

• International Journal of Computer Science & Network Security
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• 제21권1호
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• pp.192-200
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• 2021

In the mid of the December 2019, the virus has been started to spread from China namely Corona virus. It causes fatalities globally and WHO has been declared as pandemic in the whole world. There are different methods which can fit such types of values which obtain peak and get flattened by the time. The main aim of the paper is to find the best or nearly appropriate modeling of such data. The three different models has been deployed for the fitting of the data of Coronavirus confirmed patients in Pakistan till the date of 20^th November 2020. In this paper, we have conducted analysis based on data obtained from National Institute of Health (NIH) Islamabad and produced a forecast of COVID-19 confirmed cases as well as the number of deaths and recoveries in Pakistan using the Logistic model, Gompertz model and Auto-Regressive Integrated Moving Average Model (ARIMA) model. The fitted models revealed high exponential growth in the number of confirmed cases, deaths and recoveries in Pakistan.

• Journal of Species Research
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• 제10권3호
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• pp.301-320
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• 2021

During a field survey of indigenous Korean ciliates, we collected 21 unrecorded species from aquatic (freshwater and brackish water [salinity about 1.0‰] samples) and terrestrial(moss and soil samples) habitats. The morphology of these species was studied based on live observation, protargol, silver carbonate and silver nitrate impregnation, and scanning electron microscope. These species belong to seven classes as follows: 1) class Heterotrichea - Blepharisma seculum; 2) class Spirotrichea - Birojimia terricola, Bistichella variabilis, Deviata bacilliformis, Oxytricha paragranulifera, Parabistichella cf. variabilis, Steinia sphagnicola, Stichotricha aculeata, Stylonychia cf. notophora, and Tetmemena bifaria minima; 3) class Armophorea - Metopus es; 4) class Litostomatea - Acropisthium mutabile, Pseudomonilicaryon japonicum, and Rimaleptus alpinus; 5) class Phyllopharyngea - Podophrya bivacuolata; 6) class Nassophorea - Drepanomonas pauciciliata; and 7) class Oligohymenophorea - Dexiostoma campylum, Frontonia atra, Histiobalantium natans viridis, Opisthonecta minima, and Tetrahymena rostrata. Here, we provide a brief diagnosis and remark for each species.

• International Journal of Computer Science & Network Security
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• 제22권7호
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• pp.397-403
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• 2022

Enterprise resource planning (ERP) is widely adopted among enterprises and organizations. In recent years, researchers have become increasingly interested in factors related to ERP implementation success. In this paper, top management members, IT professionals, and end-users were interviewed in the study. The study used Hofstede's main cultural dimensions as a theoretical framework to identify cultural characteristics and their influence on ERP implementation within public organizations in Saudi Arabia. The study followed a qualitative methodology approach to carry on the study to investigate the national culture characteristics in Saudi Arabia that may influence ERP implementation success. The study found some culturally related factors that could influence success in ERP implantation projects in Saudi Arabia..

• 대한수학회논문집
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• 제37권4호
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• pp.969-975
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• 2022

Let R be a finite commutative ring with nonzero unity and let Z(R) be the zero divisors of R. The total graph of R is the graph whose vertices are the elements of R and two distinct vertices x, y ∈ R are adjacent if x + y ∈ Z(R). The total graph of a ring R is denoted by 𝜏(R). The independence number of the graph 𝜏(R) was found in [11]. In this paper, we again find the independence number of 𝜏(R) but in a different way. Also, we find the independent dominating number of 𝜏(R). Finally, we examine when the graph 𝜏(R) is well-covered.

• Nuclear Engineering and Technology
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• 제52권12호
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• pp.2771-2788
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• 2020

Experiments are conducted to study bubble flow behavior during the instability of subcooled boiling under uniform and non-uniform transverse heating. The non-uniform heat distribution introduces nonuniform bubble generation and condensation rates on the heated surface, which is different from the uniform heating. These bubble generation and condensation characteristics introduce a non-uniform local pressure distribution in the transverse direction, which creates an extra non-uniform pressure on the flowing bubbles. Therefore, different bubble flow behavior can be observed between uniform and non-uniform heating conditions. In the uniform heating, bubble velocity fluctuations are low, and the bubbles travel straight along the axial direction. In the non-uniform heating, more fluctuation in the bubble velocity occurs at low mass flow rate and high subcooled inlet temperatures, and reverse flow is observed. Additionally, the bubbles show a zigzag trajectory when they pass through the channel, which indicates the existence of cross flow in the transverse direction.

• Journal of Species Research
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• 제11권2호
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• pp.108-116
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• 2022

During a field survey to report unrecorded Korean ciliates, we collected five anaerobic ciliate species in two samples from freshwater and marine environments. These species belong to the classes Armophorea and Plagiopylea. The morphology of these species was studied based on live observations, protargol impregnation, and scanning electron microscope. Brachonella contorta is characterized by a size of 80-100×40-60 ㎛ in vivo, a bullet-shaped body, and about 60 oral polykinetids making 360° spiral around long axis. Brachonella pulchra is characterized by a size of 80-110×50-70 ㎛ in vivo and adoral zone composed of about 40 oral polykinetids with minimal spiralization. Metopus setosus is characterized by a size of 45-70×20-30 ㎛ in vivo, about 22 ciliary rows, very long caudal cilia, and 20 oral polykinetids. Plagiopyla nasuta is a freshwater species characterized by a size of 80-120×50-60 ㎛ in vivo, striated band present, straight extrusomes, and about 70 somatic ciliary rows. The marine Plagiopyla frontata is characterized by a size of 80-120×40-60 ㎛ in vivo, an oval to ellipsoid body shape, 50-60 somatic ciliary rows, and curved extrusomes.

• Clinics in Shoulder and Elbow
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• 제25권1호
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• pp.65-67
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• 2022

Pure anterior bilateral shoulder dislocations are rare clinical features, especially in traumatic forms. They are most often posterior, occurring during an epileptic seizure. Few cases are described in the literature, and the mechanism varies from case to case. We report a specific case of pure bilateral anterior shoulder dislocation in a 29-year-old judo player following an accident during his training and discuss the circumstances, mechanism, treatment, and prognosis.