• 한국융합학회논문지
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• 제9권4호
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• pp.137-142
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• 2018

본 연구는 송 수신 초음파 센서를 이용하여 CNG 탱크에서의 정밀한 연료량을 측정하기 위한 기초 연구로써 탱크내부 압력 및 초음파 센서의 접촉면 변경에 따른 수신감도를 분석하였다. 실험은 탱크와 센서의 접촉면을 점, 선, 면의 3가지 타입으로 변경하고 탱크 내부의 압력을 0 bar 부터 5 bar까지 1 bar 간격으로 충전하면서 측정을 진행하였다. 실험결과 탱크내부의 압력이 증가함에 따라 초음파 센서의 수신신호 값이 감소하는 경향을 확인할 수 있었다. 또한 탱크와 센서의 접촉면적이 증가할수록 수신 신호 값은 증가하지만, 노이즈 또한 증가하는 것을 확인 할 수 있었다. 이와 같은 실험 결과 초음파의 투과 특성을 이용하여 탱크내부의 기체 연료량을 측정할 수 있을 것으로 판단되며, 센서의 접촉면 변경을 통해 정밀성을 향상시킬 수 있을 것으로 판단된다.

• Steel and Composite Structures
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• 제51권2호
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• pp.153-172
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• 2024

Due to the fast development of constructions in recent years, there has been a rapid consumption of fresh water and river sand. In the production of concrete, alternatives such as sea water and sea sand are available. The near surface mounted (NSM) technique is one of the most important methods of strengthening. Aluminum alloy (AA) bars are non-rusting and suitable for usage with sea water and sand concrete (SSC). The goal of this study was to enhance the shear behaviour of SSC-beams strengthened with NSM AA bars. Twenty-four RC beams were cast from fresh water river sand concrete (FRC) and SSC before being tested in four-point flexure. All beams are the same size and have the same internal reinforcement. The major factors are the concrete type (FRC or SSC), the concrete degree (C25 or C50 with compressive strength = 25 and 50 MPa, respectively), the presence of AA bars for strengthening, the direction of AA bar reinforcement (vertical or diagonal), and the AA bar ratio (0, 0.5, 1, 1.25 and 2 %). The beams' failure mechanism, load-displacement response, ultimate capacity, and ductility were investigated. Maximum load and ductility of C25-FRC-specimens with vertical and diagonal AA bar ratios (1%) were 100,174 % and 140, 205.5 % greater, respectively, than a matching control specimen. The ultimate load and ductility of all SSC-beams were 16-28 % and 11.3-87 % greater, respectively, for different AA bar methods than that of FRC-beams. The ultimate load and ductility of C25-SSC-beams vertically strengthened with AA bar ratios were 66.7-172.7 % and 89.6-267.9 % higher than the unstrengthened beam, respectively. When compared to unstrengthened beams, the ultimate load and ductility of C50-SSC-beams vertically reinforced with AA bar ratios rose by 50-120 % and 45.4-336.1 %, respectively. National code proposed formulae were utilized to determine the theoretical load of tested beams and compared to matching experimental results. The predicted theoretical loads were found to be close to the experimental values.

• 한국인터넷방송통신학회논문지
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• 제15권6호
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• pp.257-266
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• 2015

비 볼록 발전비용함수에 대한 최적화 문제는 다항시간으로 해를 구하는 알고리즘이 알려져 있지 않아 전기분야에서는 부득이 2차 함수만을 사용하고 있다. 본 논문은 비 볼록 발전비용함수의 경제급전 최적화 문제에 대한 밸브지점 최적화 알고리즘을 제안하였다. 제안된 알고리즘은 초기 치로 최대 발전량 $P_i{\leftarrow}P_i^{max}$로 설정하고, 평균 발전단가가 $_{max}\bar{c}_i$인 발전기 i의 발전량을 밸브지점 $P_{ik}$로 감소시키는 방법을 적용하였다. 제안된 알고리즘을 13과 40-발전기 데이터에 적용한 결과 기존의 휴리스틱 알고리즘보다 좋은 성능을 보였다. 따라서 비 볼록 발전비용함수의 경제급전문제 최적 해는 각 발전기의 밸브지점 발전량으로 수렴함을 보였다.

• 한국전기전자재료학회논문지
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• 제14권9호
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• pp.703-703
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• 2001

• 대한수학회논문집
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• 제23권1호
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• pp.61-65
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• 2008

In this paper we prove that every positive solution of the third order rational difference equation $$x_{n+1}\;=\;\frac{{\beta}x_n\;+\;x_{n-2}}{A\;+\;Bx_n\;+\;x_{n-2}}$ converges to the positive equilibrium point $$\bar{x}\;=\;\frac{{\beta}\;+\;1\;-\;A}{B\;+\;1}$, where $0\;<\;{\beta}\;{\leq}\;B$, $1\;<\;A\;<\;{\beta}\;+\;1$

• 한국의사학회지
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• 제24권1호
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• pp.43-56
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• 2011

Everyone once in a life experience headaches as symptoms are very common. According to a study in a country of more than a week and as many as those who have experienced a headache amounts to 69.4%. In addition, the high reported prevalence of migraine in 30s for 80% of all migraine sufferers daily life interfere with work or was affected. In Western medicine, the cause of headaches is traction or deformation of pain induced tissue like scalp, subcutaneous tissue, muscle, fascia, extracranial arteriovenous, nerves, periosteum. But it turns out there are not cause why pain induced tissue is being tracted or deformated. Therefore, most of the western-therapy is mainly conducted with regimen for a temporary symptom reduction. Therefore, I examined how it has been developed in Chinese Ming Dynasty, the perception of headache, change in disease stage and an etiological cause. Oriental medicine in the treatment of headache is a more fundamental way to have an excellent treatment. The recognition of head in "素問($s{\grave{u}}$ $w{\grave{e}}n$)" and "靈樞($l{\acute{i}}ng$ $sh{\bar{u}}$)" began to appear in 'Soul-神($sh{\acute{e}}n$) dwelling place' and 'where to gather all the Yang-'諸陽之會($zh{\bar{u}}$ $y{\acute{a}}ng$ $zh{\bar{i}}$ $hu{\grave{i}}$)'. Also, head was recognized as '六腑($li{\grave{u}}f{\check{u}}$) 淸陽之氣($q{\bar{i}}ng$ $y{\acute{a}}ng$ $zh{\bar{i}}$ $q{\grave{i}}$) and 五臟($w{\check{u}}$ $z{\grave{a}}ng$) 精血($j{\bar{i}}ng$ $xu{\grave{e}}$) gathering place'. More specific structures such as the brain is considered a sea of marrow(髓海-$su{\check{i}}$ $h{\check{a}}i$) in "內經($n{\grave{e}}i$ $j{\bar{i}}ng$)" and came to recognized place where a stroke occurs. Accompanying development of the recognition about head, there had been changed about the perception of headache and the recognition of the cause and mechanism of headache. And the recognition of headache began to be completed in Ming Dynasty through Jin, Yuan Dynasty. Chinese Ming Dynasty, specially 樓英($l{\acute{o}}u$ $y{\bar{i}}ng$), in "醫學綱目($y{\bar{i}}xu{\acute{e}}$ $g{\bar{a}}ngm{\grave{u}}$)", first enumerated prescription in detail by separating postpartum headache. and proposed treatment of headache especially due to postpartum sepsis(敗血-$b{\grave{a}}i$ $xu{\grave{e}}$). 許浚($x{\check{u}}$ $j{\grave{u}}n$) accepted a variety of views without impartial opinion in explaining one kind of headache in "東醫寶鑑($d{\bar{o}}ng-y{\bar{i}}$ $b{\check{a}}oji{\grave{a}}n)$" 張景岳($zh{\bar{a}}ng$ $j{\check{i}}ng$ $yu{\grave{e}}$), in "景岳全書($j{\check{i}}ng$ $yu{\grave{e}}$ $qu{\acute{a}}nsh{\bar{u}}$)", established his own unique classification system-新舊表裏($x{\bar{i}}nji{\grave{u}}$ $bi{\check{a}}ol{\check{i}}$)-, and offered a clear way even in treatment. Acupuncture treatment of headache in the choice of meridian has been developed as a single acupuncture point. Using the classification of headache to come for future generation as a way of locating acupoints were developed. Chinese Ming Dynasty, there are special treatments like 導引按蹻法($d{\check{a}}o$ y ${\check{i}}n$ ${\grave{a}}n$ $ji{\check{a}}o$ $f{\check{a}}$), 搐鼻法($ch{\grave{u}}$ $b{\acute{i}}$ $f{\check{a}})$, 吐法($t{\check{u}}$ $f{\check{a}}$), 外貼法($w{\grave{a}}i$ $ti{\bar{e}}$ $f{\check{a}}$), 熨法($y{\grave{u}}n$ $f{\check{a}}$), 點眼法($di{\check{a}}n$ $y{\check{a}}n$ $f{\check{a}}$), 熏蒸法($x{\bar{u}}nzh{\bar{e}}ng$ $f{\check{a}}$), 香氣療法($xi{\bar{a}}ngq{\grave{i}}$ $li{\acute{a}}of{\check{a}}$). Most of this therapy in the treatment of headache, it is not used here, but if you use a good fit for today's environment can make a difference.

• 한국토양비료학회지
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• 제32권2호
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• pp.171-181
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• 1999

오이를 시설(施設) 재배(栽培)할 때 토양(土壤) 수분(水分) 장력(張力)의 변화(變化)에 따른 오이 생육(生育) 반응(反應)과 토양(土壤) 이화학적(理化學的) 성질(性質)을 구명하기 위하여 토양(土壤) 수분장력(水分張力)이 0.2, 1/3, 0.5그리고 1.0 bar일 때를 관수시점(灌水時點)으로 하여 겨우살이 청장오이를 공시품종(供試品種)으로 하여 오이를 재배(栽培)하면서 일련의 시험을 수행한 바 얻어진 결과를 요약하면 다음과 같다. 공시토양(供試土壤)의 토성(土性)은 수분(水分) 특성상 양토(壤土)(Loam)이며, 처리조건별 1회 요관수량(要灌水量)은 각각 4.4, 7.3, 9.6 그리고 13.4 mm였다. 물 관리(管理) 수지(收支)는 봄재배(栽培)의 경우 0.2 bar의 관수처리(灌水處理)시 관수간격(灌水間隔)은 2.3일, 관수(灌水)회수는 37회, 총관수량은 163.5 mm였고 1.0 bar는 각각 14.8일, 6회 그리고 80.3 mm였으며, 가을재배(栽培)의 경우에도 이와 같은 경향이었다. 시험 후 토양(土壤) 화학적(化學的)의 변화(變化)는 0.2 bar 처리구에서의 pH와 EC 그리고 치환성가리(加里)의 함량이 개량목표치(改良目標値)에 분포(分布)한 반면, 나머지 처리구에서는 양토(壤土)에 EC가 높았으며 유효인산함량(有效燐酸含量)과 치환성 염기함량(鹽基含量)도 높은 경향이었다. 토양(土壤)의 물리성은 1.0 bar처리시 고상(固相)은 44.9%, 용적밀도(容積密度가) $1.26g\;cm^{-3}$로 가장 높았으며, 0.2 bar처리시에는 고상(固相)이 41.7%, 용적밀도(容積密度)가 $1.09cm^{-3}$로 가장 낮았다. 근(根)의 분포(分布)는 0.2 bar처리구가 근(根) 신장생육(伸張生育)과 비대생육(肥大生育)이 가장 양호한 반면, 1/3 bar처리구에서는 가장 불량하였다. 수량(收量)을 보면 0.2 bar 처리구에서의 총수량(總收量)은 7.269 kg, 상품(上品) 과중(果重)은 5,677 kg으로 가장 높았고, 1/3 bar 처리구는 수량(收量)도 가장 낮았고 곡과율(曲果率)도 높았다.

• 대한방사선기술학회지:방사선기술과학
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• 제44권5호
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• pp.459-464
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• 2021

The detector performance is important role in acquiring the gamma rays from patients. Among parameters of detector performances, there is density, which relates to respond to gamma rays. Therefore, we confirm the detection efficiency according to various detector materials based on the density parameter using GATE (geant4 application for emission tomography) simulation tool. The NaI (density: 3.67 g/cm³), CZT (Cadimium Zinc Telluride) (density: 5.80 g/cm³), CdTe (Cadmium Telluride) (5.85 g/cm³), and GAGG (Gadoinium Aluminum Gallium Garnet) (density g/cm³) were used as detector materials. In addition, the point source and quadrant bar phantom, which is modeled for 0.5, 1.0, 1.5, and 2.0 mm thicknesses, were modeled to confirm the quatitative analysis using sensitivity (cps/MBq) and the full width at half maximum (FWHM, mm) at the 2.0 mm bar thickness containing visual evaluation. Based on the results, the sensitivity for NaI, CZT, CdTe, and GAGG detector materials were 0.12, 0.15, 0.16, and 0.18 cps/MBq. In addition, the FWHM for quadrant bar phantom in the 2.0 mm bar thickness is 3.72, 3.69, 3.70, and 3.73 mm for NaI, CZT, CdTe, and GAGG materials, respectively. Compared with performance of detector materials according to density, the high density can improve detection efficiency in terms of sensitivity and mean count. Among these detector materials, the GAGG material is efficient for detection of gamma rays.

• 비교문화연구
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• 제39권
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• pp.287-308
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• 2015

Biographical film is a genre narrativizing the actual person and history, and reproducing the character and history in a biographical film is in a dimension different from a film focused on a fiction. Discussion between these methods of narrative composition and image reproduction in a biographical film is also, in line with artistic/aesthetic problems and ethical/philosophical theses of the film text. This study discusses the phase of the way of reproduction of the actual person, $Xi{\bar{a}}o$ $H{\acute{o}}ng$ in the biographical film, The Golden Era and the time she lived in a biographical film and how the audience's discussion of the film and socio-cultural discourse differ depending on their attitude towards the cinematic introspection of the text. The narrative structure, the method of image reproduction and cinematic devices of the film, The Golden Era are completely off the point of the general format of the traditional biographical film. In The Golden Era, $Xi{\bar{a}}o$ $H{\acute{o}}ng$ and the history which she lived in did not revive depending on an omniscient subject's selective statement and meta-film structure. Ann Hui removed general, mythic images of $Xi{\bar{a}}o$ $H{\acute{o}}ng$ formed in the field of traditional Chinese culture and reproduced her through multilateral visions of a real, fictional narrator. Each spectator's judgment and interpretation of the film intervene in the multi-layered and sparse descriptions of the actual person's images and the era of the characters. Through this, it is possible to approach the uniqueness and authenticity a historical character, $Xi{\bar{a}}o$ $H{\acute{o}}ng$ and to have an opportunity of multi-layered reflection on how to secure a critical distance and make a perception in historical judgment.

• 한국운동역학회지
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• 제15권1호
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• pp.111-125
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• 2005

This study was intended to assist athletes in having a technical understanding of the Yega motion and provide basic material for improving their competitive ability by analyzing the kinematic variable of the Yega motion during the competition of the uneven parallel bar of female gymnastics. For this purpose, the game of female gymnastics participating in the uneven parallel bar game was personally videotaped using the DLT(direct linear transformation) method. An attempt was made to make a comparative analysis of the Yega motion by dividing the final first to third places into the upper group('A' group) and the sixth to eighth places into the lower group('B' group). Based on the results of actual analysis on the scenes of actual game, the following conclusion was concluded: 1. Athletes in the 'A' group showed the shorter required time on the flight phase(P3) than counterparts in the 'B' group. 2. Athletes in the 'A' group showed the little width in the horizontal displacement of the center of gravity than counterparts in the 'B' group. But athletes in the 'A' group exhibited the somewhat greater relative vertical height of the center of the body. 3. Athletes in the 'A' group showed the greater resultant velocity at the lowest point of the center of the body(E2) and at the point in time of release(E3) compared to counterparts in the 'B' group.