• Geophysics and Geophysical Exploration
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• v.26 no.2
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• pp.77-83
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• 2023

In this study, the expressions of magnetic vector and magnetic gradient tensor due to an elliptical cylinder were derived. Igneous intrusions and kimberlite structures are often shaped like elliptical cylinders with axial symmetry and different radii in the strike and perpendicular directions. The expressions of magnetic fields due to this elliptical cylinder were derived from the Poisson relation, which includes the direction of magnetization in the gravity gradient tensor. The magnetic gradient tensor due to an elliptical cylinder is derived by differentiating the magnetic fields. This method involves obtaining a total of 10 triple derivative functions acquired by differentiating the gravitational potential of the elliptical cylinder three times in each axis direction. As the order of differentiation and integration can be exchanged, the magnetic gradient tensor was derived by differentiating the gravitational potential of the elliptical cylinder three times in each direction, followed by integration in the depth direction. The remaining double integration was converted to a complex line integral along the closed boundary curve of the elliptical cylinder in the complex plane. The expressions of the magnetic field and magnetic gradient tensor derived from the complex line integral in the complex plane were shown to be perfectly consistent with those of the circular cylinder derived by the Lipschitz-Hankel integral.

• Journal of KIISE:Databases
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• v.35 no.5
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• pp.421-431
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• 2008

Recently XML is becoming a de facto standard for online data exchange between heterogeneous systems and also the research of streaming XML data filtering comes into the spotlight. Since streaming XML data filtering technique needs rapid matching of queries with XML data, it is required that the query processing should be efficiently performed. Until now, most of researches focused only on partial sharing of path expressions or efficient predicate processing and they were work for time and space efficiency. However, if containment relationship between queries is previously calculated and the lowest level query is matched with XML data, we can easily get a result that high level queries can match with the XML data without any other processing. That is, using this containment technique can be another optimal solution for streaming XML data filtering. In this paper, we suggest an efficient XML data filtering based on prime number indexing and containment relationship between queries. Through some experimental results, we present that our suggested method has a better performance than the existing method. All experiments have shown that our method has a more than two times better performance even though each experiment has its own distinct test purpose.

• The Journal of Engineering Geology
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• v.20 no.3
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• pp.311-318
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• 2010

We performed laboratory measurements of the mechanical properties and slake durability of Cretaceous shale from the Hwasun area, Korea, including highly weathered and fresh samples, yielding ranges of specific gravity of 2.14-2.88, dry density of 1.86-2.83(g/$cm^3$), water content of 0.12-6.36 (%), porosity of 1.33-20.49 (%), and absorption ratio of 0.51-8.5 (%). The absorption ratio shows a strong linear relation with porosity, expressed as Ab = 0.44P-0.09 (Ab: absorption ratio, P: porosity). Values of the slake durability index ($Id_2$) and point load intensity index ($Is_{(50)}$) of highly weathered to fresh shale are 90.07-99.33 (%) and 10.8-90.2(kg/$cm^2$), respectively. $Id_2$ is linearly related to $Is_{(50)}$, expressed as $Is(50)=1E-07e^{0.2033Id_2}$(kg/$cm^2$)($r^2=0.69$). This equation is a useful tool for estimating the $Id_2$ value for shale in the Hwasun area.

• Korean Journal of Head & Neck Oncology
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• v.14 no.2
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• pp.236-243
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• 1998

Objectives: Local invasion of the thyroid cancer that is invasion of the upper aerodigestive tract, neurovascular structures of the neck and superior mediastinum, is infrequent and comprises of 1-16% of well-differentiated thyroid cancer. However the proximity of the thyroid gland to these structures provides the means for an invasive cancer to gain ready access into theses structures and when invasion occurs, it is the source of significant morbidity and mortality. So locally invasive thyroid cancer should be removed as much as possible, but still much debates have been exist whether the surgical method should be radical or conservative. This study was desinged to evaluate the clinical characteristics and the surgical treatment of the locally invasive thyroid cancer. Material and Methods: At the department of otorhinolaryngology of Hallym university, 10 patients diagnosed as locally invasive thyroid cancer among the 81 patients treated for thyroid cancer between 1991 to 1997 were retrospectively evaluated. Results: Of the 10 patients, 3 patients had histories of previous surgical treatment with or without radiation or radioactive iodine therapy. The site of invasion of thyroid cancer were trachea(7 cases), recurrent laryngeal nerve(5 cases), mediastinal node(5 cases), esophagus(3cases), larynx(3cases), carotid artery(3 cases), pharynx(l case), and other sites(4 cases). The operation techniques included 1 partial laryngectomy and 1 partial cricoid resection, 2 shavings and 3 window resections of the trachea, 1 sleeve resection of the trachea with end-to-end anastomosis and 1 cricotracheoplasty for tracheal invasion, 2 shavings and 1 partial esophagectomies for esophageal invasion, and 1 wall shaving and 2 partial resections with $Gortex^{\circledR}$ tube reconstruction for carotid artery invasion, and so on. Conclusions: These data and review of literature suggest that the surgical method should be perfomed on the basis of individual condition and complete removal of all gross tumor with preservation of vital structures whenever possible will offer a good result.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.40 no.3
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• pp.57-66
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• 2022

Since the discovery of the inscriptions engraved with the "Chinese characters of Empress Wu(則天文字)" at 251 and 256-1, Seonjin-ri, Sacheon-si, Gyeongsangnam-do in 2003, researchers from the Gyeongnam Institute of Cultural Properties, Kwak Seung-Hoon, and Kim Chang-Gyeom have attempted to read and interpret the inscriptions. However, there are still different theories as to the origin of the "Chinese characters of Empress Wu" appearing in the inscriptions and the use of Idu(吏讀)-type notation. This study aims to clarify, this inscription was erected by the king of Silla in the late 7th and mid-8th centuries to commemorate his participation in the Sacheon and Jinju patrols and Buddhist activities, and it is revealed that the main character of the inscription is likely to be King Seongdeok who has visited southern countries. In addition, in the case of "上了言", which has been interpreted as a human name, it should be understood as an Idu-type notation or a 變體漢文 because of the use of the proposition 了, and it should be interpreted as a character that means the end of a specific act. Although it is not a religious text like 『Mugujeonggwangdaedaranigyeong (The Great Dharani Sutra)』, the reason why the "Chinese characters of Empress Wu(則天文字)" was used is that in the process of accepting the Huayan school, the royal family of Silla came into contact with the Buddhist scriptures of the period of the Empress Wu, which is closely related to the rise of the Huayan school in the Middle Ages, and it appears to have learned and used in this process.

• Management & Information Systems Review
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• v.31 no.2
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• pp.21-39
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• 2012

To examine how usage of social network services(SNS) can affect users' satisfaction through their involvement to SNS. This study first explored the usage motives on the SNS by reviewing previous studies which are from the perspectives of usage and gratification theory. The structural equation modeling(SEM) approach was used to validate the model and Lisrel was used to analyze 306 data which were collected from college students who have SNS using experiences. The results showed that the motives of information seeking and self-expression have no significant influence on affective involvement to SNS and other hypotheses were all accepted. In order to investigate the relationship of usage motives-involvement-satisfaction between different genders, path analysis in male group and female group were done respectively. The results showed that in the case of male group, the motivation of information seeking, entertainment, and self-expression have positive effect on affective involvement, while only the entertainment motive can increase the cognitive involvement. In the case of female group, socializing motive and entertainment motive have positive effect on both affective involvement and cognitive involvement, but the information seeking motive and self-expression motive can not influence the formulation of emotion in SNS.

• Journal of Embryo Transfer
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• v.18 no.3
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• pp.203-213
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• 2003

Examination of correlation between blood compositions and economic traits is very important to improve selection accuracy and predict performance ability of Hanwoo, which may be impacted into the determination of feeding management as well as marketing places. This study was aimed to provide possible procedures of Hanwoo improvement as of early individual selection based on the phenotypic correlation between blood compositions and economic traits using 866 of Hanwoo managed at National Livestock Research Institute. Phenotypic correlation between blood compositions and economic traits was estimated for steer and bulls. BUN in steer and albumin and IGF-1 in bull were highly correlated with 24 mo of weight. Average daily gain of 21 to 24 mo was highly correlated with calcium in steer and albumin in bull. Back-fat thickness and marbling score were highly correlated with BUN in steer and bull, and meat yield index was highly correlated with calcium in steer and testosterone in bull. However, BUN, which is highly correlated with meat quality, was negatively correlated with meat yield index in steer and bull.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.7 no.1
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• pp.11-22
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• 1987

A plane buoyant jet discharged vertically upward into a crossflow is analyzed by numerical solution of the governing equations of continuity, momentum and constituent transport. The turbulent transport is modelled by the Prandtl's mixing length theory. In the numerical solution procedure, the governing equations are transformed by stream function and vorticity transport, non-dimensionalyzed by discharge velocity, slot width, and parameters representing flow characteristics, and solved by Gauss-Seidel iteration method with successive underrelaxation. The numerical experiments were performed for the region of established flow of buoyant jet in the range of discharge densimetric Froude number of 4 to 32 and in the range of velocity ratio of 8 to 15, which is the ratio of discharge velocity to crossflow velocity. Variations of velocities and temperatures, flow patterns and vorticity patterns of receiving water due to buoyant jet were investigated. Also investigated are the effects of velocity ratio and discharge densimetric Froude number on the trajectories of buoyant jet. Computed are velocities, temperatures and local densimetric Froude numbers along the trajectory of the buoyant jet. Spreading rate and dispersion ratio were analyzed in terms of discharge densimetric Froude number, local densimetric Froude number and distance from the source along the jet trajectory. It was noted that the similarity law holds in both the profiles of velocity and temperatures across the jet trajectory and the integral type analysis of Gaussian distribution is applicable.

• Tunnel and Underground Space
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• v.22 no.6
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• pp.462-470
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• 2012

Implementing the generalized Hoek-Brown failure criterion in the framework of the Mohr-Coulomb criterion requires the calculation of the equivalent friction angle and cohesion. In the conventional method based on the Balmer (1952)'s theory, the tangential instantaneous friction angle and cohesion are expressed in terms of the minimum principal stress ${\sigma}_3$, which does not provide the information about the dependency of the equivalent parameters on the hydrostatic pressure and the stress path. In this study, this defect of the conventional method has been overcome by representing the equivalent parameters in terms of stress invariants. Through the example implementation of the new method, the influence of the magnitude of the hydrostatic pressure and the Lode angle on the tangential instantaneous friction angle and cohesion is investigated. It turns out that the tangential instantaneous friction angle is maximum when the stress condition is triaxial extension, while the tangential cohesion is maximum when the stress condition is triaxial compression. The dependency of the equivalent Mohr-Coulomb strength parameters on the hydrostatic pressure and the Lode angle tends to be more substantial for the favorable rockmass of larger GSI value.

• Journal of the Korean Society of Marine Environment & Safety
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• v.27 no.6
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• pp.846-855
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• 2021

Eco-friendly and renewable energy sources are actively being researched in recent times, and of shore wind power generation requires advanced design technologies in terms of increasing the capacities of wind turbines and enlarging wind turbine installation vessels (WTIVs). The WTIV ensures that the hull is situated at a height that is not affected by waves. The most important part of the WTIV is the leg structure, which must respond dynamically according to the wave, current, and wind loads. In particular, the wave load is composed of irregular waves, and it is important to know the exact dynamic response. The dynamic response analysis uses a single degree of freedom (SDOF) method, which is a simplified approach, but it is limited owing to the consideration of random waves. Therefore, in industrial practice, the time-domain analysis of random waves is based on the multi degree of freedom (MDOF) method. Although the MDOF method provides high-precision results, its data convergence is sensitive and difficult to apply owing to design complexity. Therefore, a dynamic amplification factor (DAF) estimation formula is developed in this study to express the dynamic response characteristics of random waves through time-domain analysis based on different variables. It is confirmed that the calculation time can be shortened and accuracy enhanced compared to existing MDOF methods. The developed formula will be used in the initial design of WTIVs and similar structures.