• 에너지공학
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• 제21권2호
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• pp.187-193
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• 2012

본 연구의 목적은 벽면제트영역의 열전달증진을 위해 직삼각형 로드 및 정사각형 로드를 충돌판앞에 배열한 후 로드와 충돌판 사이의 간극을 변화시키면서 열유동 특성을 실험적으로 검토한 것이다. 열전달증진율은 천이영역인 H/B=10보다는 포텐셜코어영역인 H/B=2에서 더 높게 나타났다. 본 실험범위에서 최대 열전달증진율은 직삼각형 로드를 설치할 때(H/B=2, C=1mm인 조건) 로드가 없는 평판과 비교하면 평균 약 46% 높게 나타났다. 그리고 직삼각형 로드와 정사각형 로드의 열전달증진율을 비교하면 간극 변화와 관계없이 직삼각형 로드가 정사각형 로드보다 평균 약 3~8% 정도 높게 나타났다.

• 한국수학사학회지
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• 제22권4호
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• pp.41-52
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• 2009

본 논문에서는 조선 시대의 산학서에서 다루어진 삼각형에 대한 내용을 고찰한다. 기하보다 대수에 대한 연구가 주를 이루었던 조선시대 산학 연구의 특성을 고려하면, 삼각형 자체에 대한 기하학적 탐구보다는 삼각형 모양의 밭의 넓이 측정 방법에 대한 설명이 기대된다. 그러나 예외적으로 직각삼각형인 구고에 대해서는 심도 있는 연구가 이루어졌고, 측정이라 하더라도 일반 삼각형에 대해서는 근삿값 수준으로 다루어진 것을 감안하면 삼각형 관련 내용에 대한 분석은 의의 있다고 생각된다. 조선의 산학서 <묵사집산법>, <구일집>, <산학입문>, <주해수용>, <산술관견>에 대한 고찰 결과, 삼각형 관련 내용은 크게 세 가지로 분류할 수 있 다. 측정의 필요가 있던 밭 모양과 관련한 도형의 측도, 측정 대상으로서의 도형으로부터 기하 연구 대상으로서의 도형으로 넘어가는 과도기적 내용, 서양 수학의 영향으로 인한 도형의 정의 및 성질에 대한 탐구와 타당화이다.

• 무역상무연구
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• 제29권
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• pp.197-223
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• 2006

Uniform Computer Information Transactions Act (UCITA) is the first legislative attempt in the world that deals with transaction of digital information. This however gave rise to endless controversies and as of February 10, 2003, its life as the uniform law has expired. There are four kinds of relationships that UCITA regulates for the entities involved in information trading namely, 1) Relationship between licenser and licensee 2) The triangle relationship between dealers, end-user and publisher 3) Relationship between information right transferor and transferee 4) Relationship between financier, licenser and licensee. Amongst these, the most significant one is the triangle relationship amongst the publisher, commonly known as the licenser in the mass market, end-user and dealer. At the essence of the relationship is that the dealers is liable to refund the payment for the information regarding the end user if he/she does not agree with the publisher on the license of the common market. Looking at the relationship between license transferor and transferee, the transfer of license may be prohibited but the special contract must be conspicuously carried out. The relationship financier, licenser and licensee is unique to the United States and is rather unfamiliar to us. UCITA has been criticized for preferentially protecting the benefits of licensers especially when it comes to the specific regulations for the relationship. Therefore, it is not advisable to blindly accept UCITA regulations. However, UCITA does have components that we can utilize in formulating our own digital information trade regulations, save its proprietary nature as an American law and its preferential treatment for licensers.

• 한국수학사학회지
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• 제28권6호
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• pp.301-310
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• 2015

Since Jiuzhang Suanshu, the main tools in the theory of right triangles, known as Gougushu in East Asia were algebraic identities about three sides of a right triangle derived from the Pythagorean theorem. Using tianyuanshu up to siyuanshu, Song-Yuan mathematicians could skip over those identities in the theory. Chinese Mathematics in the 17-18th centuries were mainly concerned with the identities along with the western geometrical proofs. Jeong Yag-yong (1762-1836), a well known Joseon scholar and writer of the school of Silhak, noticed that those identities can be derived through algebra and then wrote Gugo Wonlyu (勾股源流) in the early 19th century. We show that Jeong reveals the algebraic structure of polynomials with the three indeterminates in the book along with their order structure. Although the title refers to right triangles, it is the first pure algebra book in Joseon mathematics, if not in East Asia.

• Archives of Plastic Surgery
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• 제49권3호
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• pp.440-443
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• 2022

Spinal accessory nerve (SAN) palsy is typically a result of posterior triangle surgery and can present with partial or complete paralysis of the trapezius muscle and severe shoulder dysfunction. We share an atypical case of a patient who presented with SAN palsy following an injury sustained playing competitive volleyball. A 19-year-old right hand dominant competitive volleyball player presented with right shoulder weakness, dyskinesia, and pain. She injured the right shoulder during a volleyball game 2 years prior when diving routinely for a ball. On physical examination she had weakness of shoulder shrug and a pronounced shift of the scapula when abducting or forward flexing her shoulder greater than 90 degrees. Manual stabilization of the scapula eliminated this shift, so we performed scapulopexy to stabilize the inferior angle of the scapula. At 6 months postoperative, she had full active range of motion of the shoulder. SAN palsy can occur following what would seem to be a routine volleyball maneuver. This could be due to a combination of muscle hypertrophy from intensive volleyball training and stretch sustained while diving for a ball. Despite delayed presentation and complete atrophy of the trapezius, a satisfactory outcome was achieved with scapulopexy.

• 대한한방체열의학회지
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• 제1권1호
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• pp.13-19
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• 2002

Objectives : This study was performed to apply thermography as an method in diagnosis of hwabyung patients. We studied 11 Hwabyung patients who visited to chronic diseases center and circulatory oriental internal medicine of Kangnam oriental medicine hospital and 11 patients control group. Methods : Diagnosis of Hwabyung was based on the dignostic criteria of Hwabyung. The temperature was measured on Chonjung(CV17) Shimsu(B15), Kansu(B18), Kyonjong(G21) in each group. The ${\Delta}T$ was measured between Chonjung(CV17) and Chungjong(CV16), left and right Chungjong(CV16), Shimsu(B15), Kansu(B18), Kyonjong(G21) in each group. We compared the ${\Delta}T$ and DITI types between patients and control group. Results : The ${\Delta}T$ between left and right Chungjong(CV16), Shimsu(B15), Kansu(B18), Kyonjong(G21) were not statistically significant. But the ${\Delta}T$ between Chonjung(CV17) and Chungjong(CV16) was statistically significant(P<0.05) in each group. In control group, DITI type was straight 36%, diamond 27%, multiple small spot 18%, others 18%. In Hwabyung patients group, DITI type was inverse triangle 64%, multiple small spot 9.1%, round 9.1%. Conclusions : The ${\Delta}T$ between Chonjung(CV17) and Chungjong(CV16) and DITI type is considered useful diagnostic methods on Hwabyung patients.

• Imaging Science in Dentistry
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• 제45권2호
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• pp.109-115
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• 2015

Central odontogenic fibroma (COF) is a rare benign tumor that accounts for 0.1% of all odontogenic tumors. A case of COF (simple type) of the mandible in a four-year-old boy is described in this report. The patient showed asymptomatic swelling in the right inferior border of the lower jaw for one week. A panoramic radiograph showed a poorly-defined destructive unilocular radiolucent area. Cone-beam computed tomography showed expansion and perforation of the adjacent cortical bone plates. A periosteal reaction with the Codman triangle pattern was clearly visible in the buccal cortex. Since the tumor had destroyed a considerable amount of bone, surgical resection was performed. No recurrence was noted.

• 대한수학교육학회지:학교수학
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• 제4권3호
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• pp.401-413
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• 2002

The Pythagorean theorem is one of the most important theorem which appeared in school mathematics. Allowing our pupils to rediscover it in classroom, we must know how this theorem was discovered and proved. Further, we should recompose that historical knowledge to practical program which might be suitable to them So, firstly this paper surveyed the history of mathematics on discovering the Pyth-agorean theorem. This theorem was known to many ancient civilizatons: There are evidences that Babylonian and Indian had the knowledges on the relationship among the sides of a right triangle. In Zhoubi suanjing, which was ancient Chinese text book, was the proof of the Pythagorean theorem in special case. And then this paper proposed a teaching program that is composed following five tasks : 1) To draw up squares on geo-board that are various in size and shape, 2) To invent squares that are n-times bigger than a given square, 3) Discovering the Pyth-agorean theorem through the previous activity, 4) To prove the Pythagorean theorem in special case, 5) To prove the Pythagorean theorem in general case.

• 한국수학사학회지
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• 제27권1호
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• pp.13-30
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• 2014

The book ${\ll}$Ceyuan Haijing${\gg}$ studies inscribed and circumscribed circles in a right triangle and shows equations that give the diameters of the circles. We discuss the development of mathematical contents written by the scholar Yang Zhaoyun in Qing dynasty on the contents of ${\ll}$Ceyuan Haijing${\gg}$ in his book ${\ll}$Jiuyong Yandai${\gg}$. He derived equations to find the diameters of the circles based on algebraic knowledge known in the Qing dynasty. In this paper, we conclude that Yang's methods in devising the equations include the Gou-Gu Theorem, mathematical expressions derived from Gou-Gu ratio table, and the technique of interchanging triangles and events. We conclude that the Gou-Gu ratio table was a very important tool when Yang devised the equations in ${\ll}$Ceyuan Haijing${\gg}$.

• 한국농공학회지
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• 제32권E호
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• pp.20-32
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• 1990

Abstract This study was conducted to pursue the normalization of frequency distribution by making an approach to the coefficient of skewness to nearly zero through the Box-Cox transformation, to get probable flood flows can be calculated by means of the transformation equation which has been derivated by Box-Cox transformation in the annual maximum series of the applied watersheds. It has been concluded that Box-Cox transfromation is proved to be more efficient than logarithmic, square root and SMEMAX transformation which is based on the trigonometric solution of a right triangle whose three verteces repesent the smallest, median and largest observed values of a population in making the coefficient of skewness nearer to zero. Consequently it is shown that probable flood flows according to the return period based on Box-Cox transformation are closer to the observed data as compared to other methods including SMEMAX transformation and fitted probability distributions such as the three parameter lognormal and the type I extremal distribution for the applied watersheds.