• Bulletin of the Korean Mathematical Society
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• v.56 no.6
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• pp.1525-1537
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• 2019

Let ${\tilde{M}}$ be a Riemannian manifold equipped with a concircular vector field ${\tilde{X}}$ and M a submanifold (with its induced metric) of ${\tilde{M}}$. Denote by X the restriction of ${\tilde{X}}$ on M and by $X^T$ the tangential component of X, called the canonical field of M. In this article we study submanifolds of ${\tilde{M}}$ whose canonical field $X^T$ is also concircular. Several characterizations and classification results in this respect are obtained.

• Smart Structures and Systems
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• v.31 no.4
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• pp.335-349
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• 2023

Bridges constantly undergo deterioration and damage, the most common ones being concrete damage and exposed rebar. Periodic inspection of bridges to identify damages can aid in their quick remediation. Likewise, identifying components can provide context for damage assessment and help gauge a bridge's state of interaction with its surroundings. Current inspection techniques rely on manual site visits, which can be time-consuming and costly. More recently, robotic inspection assisted by autonomous data analytics based on Computer Vision (CV) and Artificial Intelligence (AI) has been viewed as a suitable alternative to manual inspection because of its efficiency and accuracy. To aid research in this avenue, this study performs a comparative assessment of different architectures, loss functions, and ensembling strategies for the autonomous segmentation of bridge components and damages. The experiments lead to several interesting discoveries. Nested Reg-UNet architecture is found to outperform five other state-of-the-art architectures in both damage and component segmentation tasks. The architecture is built by combining a Nested UNet style dense configuration with a pretrained RegNet encoder. In terms of the mean Intersection over Union (mIoU) metric, the Nested Reg-UNet architecture provides an improvement of 2.86% on the damage segmentation task and 1.66% on the component segmentation task compared to the state-of-the-art UNet architecture. Furthermore, it is demonstrated that incorporating the Lovasz-Softmax loss function to counter class imbalance can boost performance by 3.44% in the component segmentation task over the most employed alternative, weighted Cross Entropy (wCE). Finally, weighted softmax ensembling is found to be quite effective when used synchronously with the Nested Reg-UNet architecture by providing mIoU improvement of 0.74% in the component segmentation task and 1.14% in the damage segmentation task over a single-architecture baseline. Overall, the best mIoU of 92.50% for the component segmentation task and 84.19% for the damage segmentation task validate the feasibility of these techniques for autonomous bridge component and damage segmentation using RGB images.

• International Journal of Fuzzy Logic and Intelligent Systems
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• v.2 no.1
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• pp.70-77
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• 2002

This paper describes a design driven approach to drive intelligent test plan generation based on adaptive use case (3,5). Its foundation is an object-oriented software design approach which partitions design schema into design architecture of functional components called “design component”. A use case software development methodology of adaptive use case approach developed in I.I .T is employed which preserves this unit architecture on through to the actual code structure. Based on the partition design schema produced during the design phase of this methodology, a test plan is generated which includes a set of component and scenario based test. A software metric is introduced which produces an ordering of this set to enhance productivity and both promote and capitalize on test case reusability, This paper contains an application that illustrates the proposed approach.

• Journal of Korean Society for Quality Management
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• v.33 no.2
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• pp.1-12
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• 2005

An extensive literature review has been made in this paper to build the evaluation hierarchy structure for the certification of electronic commerce services. In building the evaluation hierarchy structure, major candidate evaluation factors are selected by bench marking the various certification practices, including the Malcolm Baldrige award, ISO9000, and BSC(balanced scorecard) techniques. This paper deployed principal component analysis and factor analysis techniques to develop a statistically solid and systematic evaluation model. The final evaluation model, as presented in this paper as a model for the certification of electronic commerce services, produces a numeric score on the 100% scale, which can be served as a metric for the certification decision. The AHP technique was used in converting the various qualitative and quantitative evaluation values into a single measure for the certification decision.

• Nuclear Engineering and Technology
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• v.48 no.1
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• pp.236-245
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• 2016

In a reactor coolant system of a nuclear power plant (NPP), an overpressure protection system keeps pressure in the loop within 110% of design pressure. However if the system does not work properly, pressure in the loop could elevate hugely in a short time. It would be seriously disastrous if a weak point in the pressure boundary component bursts and releases radioactive material within the containment; and it may lead to a leak outside the containment. In this study, a gross deformation that leads to a burst of pressure boundary components was investigated. Major components in the primary pressure boundary that is structurally important were selected based on structural mechanics, then, they were used to study the burst pressure of components by finite element method (FEM) analysis and by number of closed forms of theoretical relations. The burst pressure was also used as a metric of design optimization. It revealed which component was the weakest and which component had the highest margin to bursting failure. This information is valuable in severe accident progression prediction. The burst pressures of APR-1400, AP1000 and VVER-1000 reactor coolant systems were evaluated and compared to give relative margins of safety.

• International Journal of Computer Science & Network Security
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• v.23 no.12
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• pp.187-193
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• 2023

Large software systems are being produced with a noticeably higher level of quality with component-based software engineering (CBSE), which places a strong emphasis on breaking down engineered systems into logical or functional components with clearly defined interfaces for inter-component communication. The component-based software engineering is applicable for the commercial products of open-source software. Software metrics play a major role in application development which improves the quantitative measurement of analyzing, scheduling, and reiterating the software module. This methodology will provide an improved result in the process, of better quality and higher usage of software development. The major concern is about the software complexity which is focused on the development and deployment of software. Software metrics will provide an accurate result of software quality, risk, reliability, functionality, and reusability of the component. The proposed metrics are used to assess many aspects of the process, including efficiency, reusability, product interaction, and process complexity. The details description of the various software quality metrics that may be found in the literature on software engineering. In this study, it is explored the advantages and disadvantages of the various software metrics. The topic of component-based software engineering is discussed in this paper along with metrics for software quality, object-oriented metrics, and improved performance.

• Korean Journal of Materials Research
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• v.21 no.8
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• pp.468-475
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• 2011

[ $LaMeO_3$ ](Me = Cr, Co) powders were prepared using the polymeric precursor method. The effects of the chelating agent and the polymeric additive on the synthesis of the $LaMeO_3$ perovskite were studied. The samples were synthesized using ethylene glycol (EG) as the solvent, acetyl acetone (AcAc) as the chelating agent, and polyvinylpyrrolidone (PVP) as the polymer additive. The thermal decomposition behavior of the precursor powder was characterized using a thermal analysis (TG-DTA). The crystallization and particle sizes of the $LaMeO_3$ powders were investigated via powder X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), and particle size analyzer, respectively. The as-prepared precursor primarily has $LaMeO_3$ at the optimum condition, i.e. for a molar ratio of both metal-source (a : a) : EG (80a : 80a) : AcAc (8a) inclusive of 1 wt% PVP. When the as-prepared precursor was calcined at $700^{\circ}C$, only a single phase was observed to correspond with the orthorhombic structure of $LaCrO_3$ and the rhombohedral structure of $LaCoO_3$. A solid-electrolyte impedance-metric sensor device composed of $Li_{1.5}Al_{0.5}Ti_{1.5}(PO_4)_3$ as a transducer and $LaMeO_3$ as a receptor has been systematically investigated for the detection of NOx in the range of 20 to 250 ppm at $400^{\circ}C$. The sensor responses were able to divide the component between resistance and capacitance. The impedance-metric sensor for the NO showed higher sensitivity compared with $NO_2$. The responses of the impedance-metric sensor device showed dependence on each value of the NOx concentration.

• Proceedings of the Mineralogical Society of Korea Conference
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• 2002.10a
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• pp.53-67
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• 2002

As in the past, we are concerned today with the magnitudes of mineral resources and the adequacy of these resources to meet future needs. In looking at global resource issues, we should consider the need for the resource, its supply, and the environmental consequences of using it. The need for a resource can become a resource dependency, especially as the global population expands and each of us becomes increasingly dependent upon hundreds of natural materials. Therefore, our great mineral consumption makes the human population a true 'Geologic Force', which will be even more significant in the future when the global population is projected to reach alarming proportions. Although our supplies of mineral resources probably will be sufficient for the 21s1 century, the uneven distribution of minerals in the Earth's crust almost certainly will continue to be a major problem The most likely result will be major shifts in both prices and sources of supply of many mineral resources. As for energy resources, we must avoid an obsessive dependency on one fuel and expand instead to thor energy resources. Finally, because the use of resources affects the environment, we need to focus on resource exploitation and global pollution, particularly in regard to ground water and arable land. We must manage our resources so as to be in balance with our environment. And the accelerated industrialization of South Korean economy over the last three decades has resulted in the mass consumption of nuneral commodities. South Korea has around 50 useful mineral commodities for the mineral industry, among 330 kinds of minerals described. The component ratio of the mining industry sector of the gross national production(GNP) in South Korea dropped from $1.2\%\;in\;1971\;to\;0.34\%$ in 1997 due to the rapid growth of other industries In the countxy. During the period from 1971 to 1997, the average growth rate of mineral consumption in South Korea was $9.13\%$ yearly and that of GNP per capita was $14.97\%$. The mineral consumptions per capita showed a continual Increase during the last 30 years as follows(parenthesis. GNP per capita): 0.99 metric tons in 1971($\$289$), 3.83 metric tons in 1989($\$5,210$), 6.11 metric tons in 1995 ($\$10,037$), and 6.66 metric tons in 1997($9,511). The total amount of mineral consumption in South Korea was 33 million tons of 32 mineral commodities in 1971, and 306 million metric tons of 47 mineral commodities In 1997.

• Proceedings of the KSEEG Conference
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• 2002.10a
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• pp.53-67
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• 2002

As in the past, we are concerned today with the magnitudes of mineral resources and the adequacy of these resources to meet future needs. In looking at global resource issues, we should consider the need for the resource, its supply, and the environmental consequences of using it. The need for a resource can become a resource dependency, specially as the global population expands and each of us becomes Increasingly dependent upon hundreds of natural materials. Therefore, our great mineral consumption makes the human population a true “Geologic Force”, which will be even more significant in the future when the global population is projected to reach alarming proportions. Although our supplies of mineral resources probably will be sufficient for the 21st century, the uneven distribution of minerals in the Earth's crust almost certainly will continue to be a major problem. The most likely result will be major shifts in both prices and sources of supply of many mineral resources. As for energy resources, we must avoid an obsessive dependency on one fuel and expand instead to other energy resources. Finally, because the use of resources affects the environment, we need to focus on resource exploitation and global pollution, particularly in regard to ground water and arable land. We must manage our resources so as to be in balance with our environment. And the accelerated industrialization of South Korean economy over the last three decades has resulted in the mass consumption of mineral commodities. South Korea has around 50 useful mineral commodities for the mineral industry, among 330 kinds of minerals described. The component ratio of the mining industry sector of the gross national production(GNP) in South Korea dropped from 1.2% in 1971 to 0.34% in 1997 due to the rapid growth of other industries in the country. During the period from 1971 to 1997, the average growth rate of mineral consumption in South Korea was 9.13% yearly and that of GMP per capita was 14.97%. The mineral consumptions per capita showed a continual increase during the last 30 years as follows(parenthesis: GW per capita); 0.99 metric tons in 1997($289), 3.83 metric tons in 1989($5, 210), 6.11 metric tons in 1995 ($10, 037), and 6.66 metric tons in 1997($9, 511). The total amount of mineral consumption in South Korea was 33 million tons of 32 mineral commodities in 1971, and 306 million metric tons of 47 mineral commodities in 1997.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.4
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• pp.404-408
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• 1999

To analyze the possibility for the genetic improvement at the early period at 60 days of age in tilapia, Oreochromis niloticus. Genetic parameters on eight traits, total length (TL), standrad length (SL), head length (HL), body depth (BD), body height at the origin of dorsal fin (BH1), length from the origin of dorsal fin to the origin of dorsal fin (BH2), snout length (SNL), and body weight (BW), were estimated by sib analysis. Heritabilities estimated from sire, dam and full-sib components were moderately high in all metric traits, ranged 0.08$\~$0.70, 0.22$\~$0.41 and 0.18$\~$0.55, respectively. Those of SL from sire, dam, and full-sib component were estimated as 0.13, 0.22, and 0.18, respectively, Besides BH1, BH2 also showed high heritabilities, $h^2_s$ (0.08), $h^2_d$ (0.38) and $h^2_{s+d}$ (0.23), indicating that it would be a new production-related metric trait for selection. Among the metric traits, phenotypic and genetic correlation coefficients were ranged from 0,86 to 0.97 and from 0.90 to 0.99, respectively. Thus, genetic improvement would be possible at the early growth rate by the individual selection in tilapia.