• 대한기계학회:학술대회논문집
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• 대한기계학회 2004년도 춘계학술대회
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• pp.48-53
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• 2004

This paper suggested the method determing the stress intensity factor (SIF) for functionally gradient materials (FGMs) by photo elastic experimental method. The SIF for the center crack in a finite rectangulat plate with a linear variation of shear modulus with constant density and Poisson's ratio along the direction of the crack under mode I static loading is obtained. The exponential and linear variation of stress fields are used for obtaining the SIF. The greater crack length, the increaser the difference of the SIF between right and left side crack tip.

• Kyungpook Mathematical Journal
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• 제61권1호
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• pp.11-21
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• 2021

We study the structure of rings whose factor rings modulo nonzero proper ideals are right duo; such rings are called right FD. We first see that this new ring property is not left-right symmetric. We prove for a non-prime right FD ring R that R is a subdirect product of subdirectly irreducible right FD rings; and that R/N∗(R) is a subdirect product of right duo domains, and R/J(R) is a subdirect product of division rings, where N∗(R) (J(R)) is the prime (Jacobson) radical of R. We study the relation among right FD rings, division rings, commutative rings, right duo rings and simple rings, in relation to matrix rings, polynomial rings and direct products. We prove that if a ring R is right FD and 0 ≠ e2 = e ∈ R then eRe is also right FD, examining that the class of right FD rings is not closed under subrings.

• 대한수학회보
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• 제59권4호
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• pp.853-868
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• 2022

We study the structure of right regular commutators, and call a ring R strongly C-regular if ab - ba ∈ (ab - ba)²R for any a, b ∈ R. We first prove that a noncommutative strongly C-regular domain is a division algebra generated by all commutators; and that a ring (possibly without identity) is strongly C-regular if and only if it is Abelian C-regular (from which we infer that strong C-regularity is left-right symmetric). It is proved that for a strongly C-regular ring R, (i) if R/W(R) is commutative, then R is commutative; and (ii) every prime factor ring of R is either a commutative domain or a noncommutative division ring, where W(R) is the Wedderburn radical of R.

• 센서학회지
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• 제33권2호
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• pp.98-104
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• 2024

This study proposes a method to overcome the limited detection range of short-baseline stereo cameras (SBSCs). The proposed method includes two steps: (1) predicting an unscaled initial depth using monocular depth estimation (MDE) and (2) adjusting the unscaled initial depth by a scale factor. The scale factor is computed by triangulating the sparse visual keypoints extracted from the left and right images of the SBSC. The proposed method allows the use of any pre-trained MDE model without the need for additional training or data collection, making it efficient even when considering the computational constraints of small platforms. Using an open dataset, the performance of the proposed method was demonstrated by comparing it with other conventional stereo-based depth estimation methods.

• The Journal of Advanced Prosthodontics
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• 제7권1호
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• pp.51-55
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• 2015

PURPOSE. Bone density at implant placement site is a key factor to obtain the primary stability of the fixture, which, in turn, is a prognostic factor for osseointegration and long-term success of an implant supported rehabilitation. Recently, an implant motor with a bone density measurement probe has been introduced. The aim of the present study was to test the objectiveness of the bone densities registered by the implant motor regardless of the operator performing them. MATERIALS AND METHODS. A total of 3704 bone density measurements, performed by means of the implant motor, were registered by 39 operators at different implant sites during routine activity. Bone density measurements were grouped according to their distribution across the jaws. Specifically, four different areas were distinguished: a pre-antral (between teeth from first right maxillary premolar to first left maxillary premolar) and a sub-antral (more distally) zone in the maxilla, and an interforaminal (between and including teeth from first left mandibular premolar to first right mandibular premolar) and a retroforaminal (more distally) zone in the lower one. A statistical comparison was performed to check the inter-operators variability of the collected data. RESULTS. The device produced consistent and operator-independent bone density values at each tooth position, showing a reliable bone-density measurement. CONCLUSION. The implant motor demonstrated to be a helpful tool to properly plan implant placement and loading irrespective of the operator using it.

• Journal of Yeungnam Medical Science
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• 제34권2호
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• pp.270-274
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• 2017

A nodular density was detected on a chest radiograph taken from a 57-year-old Korean woman who was visiting a hospital for a routine check. Chest computed tomography revealed a 4.8 cm lobulated mass in the right lung and another focal nodular lesion in the left lung; biopsies of both lungs revealed adenocarcinoma. We conducted DNA sequencing and peptide nucleic acid clamping to investigate the potential double primary lung cancer. The results verified that the mass in the right lung had a mutation in the epidermal growth factor receptor, whereas the nodule in the left lung had a wild-type sequence, showing that these two were genetically different cancers from one another. Thus, we demonstrate that genetic testing is useful in determining double primary lung cancer, and we herein report on this case.

• Journal of Acupuncture Research
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• 제17권3호
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• pp.25-35
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• 2000

Objectives : The characteristic of meridian system has been similar to this of electric potentials in human body. Therefore to measure the electric potentials in healthy volunteers and patients, and to find out the characteristic of meridian system and also to do that of differences between them. Methods : Twenty-nine healthy volunteers, thirty patients diagnosed as a cerebral infarction and wind-syndrome caused by hyperactivity of the liver-yang(肝陽化風) were examined into electric potential of well(井穴) and sea(合穴) points in branches of the twelve meridians by physiograph. Results : Measurements were analyzed by factor analysis, then we obtained that both the right and the left electric potential of well and sea points in branches of the twelves meridians in healthy volunteers were divided into two factors, hand meridian and foot meridian. Where as the left electric potential of those in patients with cerebral infarction were divided into three factors, one is foot meridian, another is hand meridian with the exception of large intestine meridian, and the other is large intestine meridian and also the right electric potential were divided into three factors, foot meridian, hand meridian with the exception of large intestine and lung meridian, and large intestine and lung meridian. Conclusions : In the results, healthy volunteers differ from patients in characteristic of electrical potentials, which means that we are able to catch the characteristic of meridian system by electrical potentials of well and sea points.

• 한국실내디자인학회논문집
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• 제18권1호
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• pp.35-42
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• 2009

In this study, the author aims to examine that the image for specific space coming through vision is to reveal how people perceive the space through vision and whether the perceived space includes the role as the catalyst that causes the following activities. It is believed that the fact which elements are remembered as the whole expression as well as the memorized images that humans have regarding the space should act as the important factor in terms of space perception. The conclusions from this study are as follow; 1) By analyzing the frequency of observation time that were obtained from the examinee, it was possible to classify the property of observation with S areas. Besides, it was possible to the meanings that the design elements have in each area. The establishment of the areas are considered as the important factor to examine which design elements have drawn the attention. 2) In case of I area which showed the most design factors that would lead examinee's vision or have interests in the examinee views, it showed that it stared the lower parts from the middle of the Image spatially, which was the most stable position from the image with strong tendency for staring at this area. 3) The most frequently stared area was the lower part of the middle, however, while the I area gazed the right side of the middle, II area faced the left side more so that it was revealed that it stared at the lower part of the middle and right side, then, moved to left. 4) Despite the frequent observation, some areas had very low or few observation data records and the area which was designed with monotonous color with relatively large size was also involved here so that it was identified that the simply treated area in design was rarely gazed.

• 대한영양사협회학술지
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• 제14권1호
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• pp.13-22
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• 2008

This study was done to investigate satisfaction of fifth-grade(n=264) and sixth-grade(n=117) students from school foodservice in five elementary schools in Won-ju. On a scale of 1 to 5, with 1 being very poor and 5 being very good, overall satisfaction from school foodservice was found to be 3.21$\pm$0.98('so-so$\sim$satisfaction'). The highest satisfactory factor was neatness of foodservice staffs(3.79$\pm$1.00), while the lowest satisfactory factor was the students' overall opinions of school foodservice(3.03$\pm$1.06). The biggest unsatisfactory factor was found to be 'bland food'. 'Enhancement of taste'(49.08%) caused the most complaints against school foodservice. Soup was identified as the type of food most likely to be left over, and there was some significant difference between fifth-graders and sixth-graders. The reason cited most often for leftovers was unfavorable menus(33.42%). Students were more likely to try foods which were unfamiliar to them and also foods they previously disliked as a result of using school foodservice(28.87%). Also significant, when the meal director was present during the meal service, satisfaction was markedly higher than when the director was not present.

• 한국초등수학교육학회지
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• 제1권1호
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• pp.99-108
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• 1997

교육 분야에 상당히 많은 연구가 있었고, 교육 개혁 또한 수 차례에 걸쳐 이루어졌다. 그러나 실질적으로 교육에서 진정으로 도움이 될 만한 발전을 이루지는 못했다고 말할 수 있다. 많은 교육 연구와 교육 논쟁들은 교육을 하나의 과학으로 만들려는 시도를 저지해 왔다. 그러나 대부분의 연구물들은 교육에 있어서 아주 중요한 요소인 인간 개인의 특질적 성향에 대한 요소를 빠트리고 연구를 전개해 온 것이다. 과학자들이 실험실이나 컨트롤된 환경에서 동물들에 사용했던 연구 기술이나 연구 과정 등은 교육 환경에 처한 인간에게는 효과적으로 적용될 수 없는 것이다. 따라서, 우리는 우리가 해 온 과거로부터 잘못된 것을 인지하고 교육에 있어서는 늘상 인간이라는 요소를 염두에 두고 교육이 진정으로 원하는 것이 무엇인지 - 학생 그리고 교사가 원하는 것이 무엇인지를 - 결정해서 우리의 교육 목표와 우리의 방법을 일치시키고, 미래를 바라볼 수 있어야 한다.