• The Journal of the Korea institute of electronic communication sciences
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• v.17 no.2
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• pp.237-244
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• 2022

We measured the clutter loss (CL) and building entry loss (BEL) of signals in a low-rise high-density suburban environment. Three propagation models for BEL, CL, and a combination of BEL and CL were measured in the selected environment. We then derived the figures when the BEL was combined with the CL. At the two frequencies, the measured value of combination of BEL and CL is 27.55 dB and 26.12dB, respectively, and the differences between the measured value and the sum were -4.19 dB and 5.82 dB. Considering that the measurement was performed inside a building, such a difference seems to be small. Therefore, when BEL and CL were measured separately and summed, and then combined and summed, differences of -4.19 dB and 5.82 dB were apparent. This this result can be referenced when similar case of a propagation model was analyzed.

• Journal of Korean Society for Atmospheric Environment
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• v.22 no.E2
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• pp.89-98
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• 2006

Two tobacco cultivars (Nicotiana tabacum L.), Bel-B and Bel-W3, tolerant and sensitive to ozone, respectively, were grown in a greenhouse supplied with charcoal filtered air and exposed to 200 ppb ozone for 4 hr. Effects on chlorophyll fluorescence, net photosynthesis, and stomatal conductance are described. Quantum yield was calculated from chlorophyll fluorescence and the initial slope of the assimilation-light curve measured by the gas exchange method. Only the sensitive cultivar, Bel-W3, developed visual injury symptoms on up to 50% of the $5^{th}$ leaf. The maximum net photosynthetic rate of ozone-treated plants was reduced 40% compared to control plants immediately after ozone fumigation in the tolerant cultivar; however, photosynthesis recovered by 24 hr post fumigation and remained at the same level as control plants. On the other hand, ozone exposure reduced maximum net photosynthesis up to 50%, with no recovery, in the sensitive cultivar apparently causing permanent damage to the photosystem. Reductions in apparent quantum efficiency, calculated from the assimilation-light curve, differed between cultivars. Bel-B showed an immediate depression of 14% compared to controls, whereas, Bel-W3 showed a 27% decline. Electron transport rate (ETR), at saturating light intensity, decreased 58% and 80% immediately after ozone treatment in Bel-B and Bel-W3, respectively. Quantum yield decreased 28% and 36% in Bel-B and Bel-W3, respectively. It can be concluded that ozone caused a greater relative decrease in linear electron transport than maximum net photosynthesis, suggesting greater damage to PSII than the carbon reduction cycle.

• Structural Engineering and Mechanics
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• v.64 no.3
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• pp.323-328
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• 2017

This paper presents a three-dimensional finite element method analysis of repairing plate with bonded composite patch subjected to tensile load. The effect of the corrosion on the damage of the adhesive (FM73) in the length of two horizontal cracks on the both sides is presented. The obtained results show that the crack on the left side creates a very extensive area of the damaged zone and gives values of the stress intensity factor (SIF) higher than that on the right side. We can conclude that the left crack is more harmful (dangerous) than that on the right side.

• Structural Engineering and Mechanics
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• v.55 no.1
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• pp.65-78
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• 2015

In recent years, implants have gained growing importance in all areas of medicine. The success of the treatment depends on many factors affecting the bone-implant, implant-abutment and abutment-prosthesis interfaces. In this paper, static and dynamic behaviors of the dental prosthesis are investigated. Three-dimensional finite element models of dental prosthesis were constructed. Dynamic loads in 5 sec applied on occlusal surface. Therefore, FEA was selected for use in this study to examine the effect of the static and dynamic loads on the stress distribution for an implant-supported fixed partial denture and supporting bone tissue.

• Journal of Applied and Pure Mathematics
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• v.5 no.3_4
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• pp.211-222
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• 2023

In this paper, we study the following hybrid Caputo-Fabrizio fractional differential equation: ^𝐶𝓕_α𝕯^θ_ϑ [ω(ϑ) - 𝕱(ϑ, ω(ϑ))] = 𝕲(ϑ, ω(ϑ)), ϑ ∈ 𝕵 := [a, b], ω(α) = 𝜑_α ∈ ℝ, The result is based on a Dhage fixed point theorem in Banach algebra. Further, an example is provided for the justification of our main result.

• Structural Engineering and Mechanics
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• v.60 no.3
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• pp.405-412
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• 2016

Bone is a living material with a complex hierarchical structure that gives it remarkable mechanical properties. Bone constantly undergoes mechanical. Its quality and resistance to fracture is constantly changing over time through the process of bone remodeling. Numerical modeling allows the study of the bone mechanical behavior and the prediction of different trauma caused by accidents without expose humans to real tests. The aim of this work is the modeling of the femur fracture under static solicitation to create a numerical model to simulate this element fracture. This modeling will contribute to improve the design of the indoor environment to be better safe for the passengers' transportation means. Results show that vertical loading leads to the femur neck fracture and horizontal loading leads to the fracture of the femur diaphysis. The isotropic consideration of the bone leads to bone fracture by crack propagation but the orthotropic consideration leads to the fragmentation of the bone.

• Journal of Plant Biotechnology
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• v.38 no.2
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• pp.162-168
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• 2011

High salinity is a common stress condition that adversely affects plant growth and crop production. In response to various environmental stresses, plants activate a number of defense genes that function to increase the tolerance. To isolate Arabidopsis genes that are involved in abiotic stress responses, we carried out genetic screening using various mutant lines. Among them, the blh8 ($\b{B}$EL1-$\b{L}$ike $\b{H}$omeodomain $\underline{8}$) mutant specifically shows chlorotic phenotypes to ionic (specifically, $Na^+$ and $K^+$) stresses, but no differences in root growth. In addition, BLH8 is related to plant development and abiotic stress as predicted by a Graphical Gaussian Model (GGM) network program. It implies that BLH8 functions as a putative transcription factor related to abiotic stress responses. Collectively, our results show that gene network analysis is a useful tool for isolating genes involved in stress adaptation in plants.

• Wind and Structures
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• v.29 no.6
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• pp.371-387
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• 2019

In the present paper, a simple refined nth-higher-order shear deformation theory is applied for the free vibration analysis of laminated composite plates. The proposed displacement field is based on a novel kinematic in which include the undetermined integral terms and contains only four unknowns, as against five or more in case of other higher-order theories. The present theory accounts for adequate distribution of the transverse shear strains through the plate thickness and satisfies the shear stress-free boundary conditions on the top and bottom surfaces of the plate, therefore, it does not require problem dependent shear correction factor. The governing equations of motion are derived from Hamilton's principle and solved via Navier-type to obtain closed form solutions. The numerical results of non-dimensional natural frequencies obtained by using the present theory are presented and compared with those of other theories available in the literature to verify the validity of present solutions. It can be concluded that the present refined theory is accurate and efficient in predicting the natural frequencies of isotropic, orthotropic and laminated composite plates.

• Structural Engineering and Mechanics
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• v.57 no.4
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• pp.717-731
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• 2016

In orthopedic surgery and more especially in total arthroplastie of hip, the fixing of the implants generally takes place essentially by means of constituted surgical polymer cement. The damage of this materiel led to the fatal rupture and thus loosening of the prosthesis in total hip, the effect of over loading as the case of tripping of the patient during walking is one of the parameters that led to the damage of this binder. From this phenomenon we supposed that a remain of bone is included in the cement implantation. The object of this work is to study the effect of this bony inclusion in the zones where the outside conditions (loads and geometric shapes) can provoke the fracture of the cement and therefore the aseptic lousing of the prosthesis. In this study it was assumed the presence of two bones -type inclusions in this material, one after we analyzed the effect of interaction between these two inclusions damage of damage to this material. One have modeled the damage in the cement around this bone inclusion and estimate the crack length from the damaged cement zone in the acetabulum using the finite element method, for every position of the implant under the extreme effort undergone by the prosthesis. We noted that the most intense stress position is around the sharp corner of the bone fragment and the higher level of damage leads directly the fracture of the total prosthesis of the hip.

• Structural Engineering and Mechanics
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• v.59 no.1
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• pp.123-132
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• 2016

Many military and commercial aging aircrafts flying beyond their design life may experience severe crack and corrosion damage, and thus lead to catastrophic failures. In this paper, were used in a finite element model to evaluate the effect of corrosion on the adhesive damage in bonded composite repair of aircraft structures. The damage zone theory was implemented in the finite element code in order to achieve this objective. In addition, the effect of the corrosion, on the repair efficiency. Four different patch shapes were chosen to analyze the adhesive damage: rectangular, trapezoidal, circular and elliptical. The modified damage zone theory was implemented in the FE code to evaluate the adhesive damage. The obtained results show that the adhesive damage localized on the level of corrosion and in the sides of patch, and the rectangular patch offers high safety it reduces considerably the risk of the adhesive failure.