• 마케팅과학연구
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• 제19권1호
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• pp.37-46
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• 2009

The Census Bureau of the Department of Commerce announced in May 2008 that U.S. retail e-commerce sales for 2006 reached $ 107 billion, up from $ 87 billion in 2005 - an increase of 22 percent. From 2001 to 2006, retail e-sales increased at an average annual growth rate of 25.4 percent. The explosive growth of E-Commerce has caused profound changes in marketing channel relationships and structures in many industries. Despite the great potential implications for both academicians and practitioners, there still exists a great deal of uncertainty about the impact of the Internet channel introduction on distribution channel management. The purpose of this study is to investigate how the ownership of the new Internet channel affects the existing channel members and consumers. To explore the above research questions, this study conducts well-controlled mathematical experiments to isolate the impact of the Internet channel by comparing before and after the Internet channel entry. The model consists of a monopolist manufacturer selling its product through a channel system including one independent physical store before the entry of an Internet store. The addition of the Internet store to this channel system results in a mixed channel comprised of two different types of channels. The new Internet store can be launched by the independent physical store such as Bestbuy. In this case, the physical retailer coordinates the two types of stores to maximize the joint profits from the two stores. The Internet store also can be introduced by an independent Internet retailer such as Amazon. In this case, a retail level competition occurs between the two types of stores. Although the manufacturer sells only one product, consumers view each product-outlet pair as a unique offering. Thus, the introduction of the Internet channel provides two product offerings for consumers. The channel structures analyzed in this study are illustrated in Fig.1. It is assumed that the manufacturer plays as a Stackelberg leader maximizing its own profits with the foresight of the independent retailer's optimal responses as typically assumed in previous analytical channel studies. As a Stackelberg follower, the independent physical retailer or independent Internet retailer maximizes its own profits, conditional on the manufacturer's wholesale price. The price competition between two the independent retailers is assumed to be a Bertrand Nash game. For simplicity, the marginal cost is set at zero, as typically assumed in this type of study. In order to explore the research questions above, this study develops a game theoretic model that possesses the following three key characteristics. First, the model explicitly captures the fact that an Internet channel and a physical store exist in two independent dimensions (one in physical space and the other in cyber space). This enables this model to demonstrate that the effect of adding an Internet store is different from that of adding another physical store. Second, the model reflects the fact that consumers are heterogeneous in their preferences for using a physical store and for using an Internet channel. Third, the model captures the vertical strategic interactions between an upstream manufacturer and a downstream retailer, making it possible to analyze the channel structure issues discussed in this paper. Although numerous previous models capture this vertical dimension of marketing channels, none simultaneously incorporates the three characteristics reflected in this model. The analysis results are summarized in Table 1. When the new Internet channel is introduced by the existing physical retailer and the retailer coordinates both types of stores to maximize the joint profits from the both stores, retail prices increase due to a combination of the coordination of the retail prices and the wider market coverage. The quantity sold does not significantly increase despite the wider market coverage, because the excessively high retail prices alleviate the market coverage effect to a degree. Interestingly, the coordinated total retail profits are lower than the combined retail profits of two competing independent retailers. This implies that when a physical retailer opens an Internet channel, the retailers could be better off managing the two channels separately rather than coordinating them, unless they have the foresight of the manufacturer's pricing behavior. It is also found that the introduction of an Internet channel affects the power balance of the channel. The retail competition is strong when an independent Internet store joins a channel with an independent physical retailer. This implies that each retailer in this structure has weak channel power. Due to intense retail competition, the manufacturer uses its channel power to increase its wholesale price to extract more profits from the total channel profit. However, the retailers cannot increase retail prices accordingly because of the intense retail level competition, leading to lower channel power. In this case, consumer welfare increases due to the wider market coverage and lower retail prices caused by the retail competition. The model employed for this study is not designed to capture all the characteristics of the Internet channel. The theoretical model in this study can also be applied for any stores that are not geographically constrained such as TV home shopping or catalog sales via mail. The reasons the model in this study is names as "Internet" are as follows: first, the most representative example of the stores that are not geographically constrained is the Internet. Second, catalog sales usually determine the target markets using the pre-specified mailing lists. In this aspect, the model used in this study is closer to the Internet than catalog sales. However, it would be a desirable future research direction to mathematically and theoretically distinguish the core differences among the stores that are not geographically constrained. The model is simplified by a set of assumptions to obtain mathematical traceability. First, this study assumes the price is the only strategic tool for competition. In the real world, however, various marketing variables can be used for competition. Therefore, a more realistic model can be designed if a model incorporates other various marketing variables such as service levels or operation costs. Second, this study assumes the market with one monopoly manufacturer. Therefore, the results from this study should be carefully interpreted considering this limitation. Future research could extend this limitation by introducing manufacturer level competition. Finally, some of the results are drawn from the assumption that the monopoly manufacturer is the Stackelberg leader. Although this is a standard assumption among game theoretic studies of this kind, we could gain deeper understanding and generalize our findings beyond this assumption if the model is analyzed by different game rules.

• 한국실내디자인학회논문집
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• 제23권6호
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• pp.87-94
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• 2014

Today, the growing number of international architects enters the open market of South Korean architecture and interior from exhibition spaces such as art galleries to buildings of major companies. Establishing new local landmarks, their works have a considerable influence on the development of architecture. Among many, French architect Jean-Michel Wilmotte has worked consistently in South Korea. The purpose of this study is to analyze and put together the expression characteristic of the interior design in his exhibition spaces including Gana Art Gallery. Jean-Michel Wilmotte has designed based on the history, culture, society, and arts in France and other European countries, and is influenced by architects like Charles Rennie Mackintosh, Josef Hoffmann, and Carlo Scarpa. Such an influence is shown in the form of contrast between verticality and horizontality as well as the fortification in his modern classical characteristic, which is one of his expression characters. In his work of improving the ancient architecture, Wilmotte is good at creating a modern space through contextual expression, and the textural contrast between materials of the past and the present. Thus I performed an analysis of the expression characteristic of the interior design in National Museum of Contemporary Art of Chiado in Lisbon, Cognac Hennessy Museum in France, Gana Art Gallery in Korea, Mus$\acute{e}$e du Pr$\acute{e}$sident Jacques Chirac in Sarran, France, Ullens Center for Contemporary Art (UCCA) in Beijing, and lastly Mus$\acute{e}$e d'Orsay in Paris. The results show that he maintains the spatial context by applying contemporary design to the preserved existing structure, continues the flow of exhibition through the lightings in the corridors and on the ceiling, and seeks for a balance by adding vertical or horizontal elements to the elevation. In the interior, the staircase and exhibition structure are turned into objects, and the contrasting texture of the wall vitalizes the space. Wilmotte redesigns the space of the past and the present by using indirect joint that allows an organic connection of the old and new structures, and by minimizing the conflict between the two elements through prefabrication. The expression character of his interior design will be potential resources for architects and interior designers to develop their own design languages.

• 한국지반공학회논문집
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• 제21권4호
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• pp.71-81
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• 2005

지반의 표면에서 비파괴적으로 지반의 구조나 하부강성을 구하는 표면파 기법의 초기형태는 2차원 평면파의 측정과 해석에 기반을 두었으나, 이후 3차원 입체파에 기반을 두는 형태로 발전하였다. 그러나 체적파의 간섭, 근접장 효과, 표면파 측정해상도의 한계 등으로 인하여 3차원 입체파의 활용은 제한적이었고, 측정 지반을 대표하는 1차원 평가에 국한되었다. 본 연구에서는 SASW 시험의 수치모델링을 통하여 수직 레일레이파, 수평 레일레이파, 러브파 등의 표면파 전파 특성을 3차원 영역에서 심도있게 고찰하였으며, 표면파의 근접장 효과를 최소화하기 위한 새로운 필터조건을 정립하였고, 결과적으로 CAP(common-array-profiling)-SASW라는 기법이라고 하는 개선된 표면파 기법을 제안하게 되었다. CAP-SASW 기법의 적용으로 인하여 좁은 폭의 지반단면에 대한 전단파 속도 주상도 평가가 가능하게 되었고, 지반 단면에 대한 2차원 지반강성 평가도 가능하게 되었다. 본 연구에서 제안한 기법의 검증을 위하여 자연 지반을 대상으로 하여 CAP-SASW 시험, 기존 SASW 시험, 다운홀 시험 등을 수행하여 획득된 전단파 주상도를 비교하였다.

• 한국운동역학회지
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• 제13권3호
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• pp.81-98
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• 2003

The purpose of this study is to closely examine kinematic characteristics by jump phase of Li Xiaopeng motion in horse vaulting and provide the training data. In doing so, as a result of analyzing kinematic variables through 3-dimensional cinematographic using the high-speed video camera to Li Xiaopeng motion first performed at the men's vault competition at the 14th Busan Asian Games, the following conclusion was obtained. 1. It was indicated that at the post-flight, the increase of flight time and height and twisting rotational velocity has a decisive effect on the increase of twist displacement. And Li Xiaopeng motion showed longer flight time and higher flight height than Ropez motion with the same twist displacement of entire movement. Also the rotational displacement of the trunk at peak of COG was much short of $360^{\circ}$(one rotation) but twist displacement showed $606^{\circ}$. Likewise, Li Xiaopeng motion was indicated to concentrate on twist movement in the early flight. 2. It was indicated that at the landing, Li Xiaopeng motion gets the hip to move back, the trunk to stand up and the horizontal velocity of COG to slow down. This is thought to be the performance of sufficient landing, resulting from large security of rotational displacement of airborne and twist displacement. 3. It was indicated that at the board contact, Li Xiaopeng motion made a rapid rotation uprighting the trunk to recover slowing velocity caused by jumping with the horse in the back, and has already twisted the trunk nearly close to $40^{\circ}$ at board contact. Under the premise that elasticity is generated without the change of the feet contacting the board, it will give an aid to the rotation and twist of pre-flight. Thus, in the round-oH phase, the tap of waist according to the fraction and extension of hip joint and arm push is thought to be very important. 4. It was indicated that at the pre-flight, Li Xiaopeng motion showed bigger movement than the techniques of precedented studies rushing to the horse, and overcomes the concern of relatively low power of jump through the rapid rotation of the trunk. Li Xiaopeng motion secured much twist distance, increased rotational distance with the trunk bent forward, resulting in the effect of rushing to the horse. 5. At horse contact, Li Xiaopeng motion makes a short-time contact, and maintains horse take-off angle close to vertical, contributing to the increase of post-flight time and height. This is thought to be resulted from rapid move toward movement direction along with the rotational velocity of trunk rapidly earned prior to horse contact, and little shave of rotation axis according to twist motion because of effective twist in the same direction.

• 자원환경지질
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• 제13권3호
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• pp.185-192
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• 1980

원유 비축시설 건설을 위한 예비조사로서 지표지질조사, 탄성파탐사 및 시추조사를 실시하고, 그 결과를 종합분석하여 본보고서를 작성하였다. 본지역의 지질은 백악기의 중성화산암류인 안산암과 이를 관입한 후기 백악기의 불국사통에 속하는 섬장암과 반화강암으로 구성되어 있으며, 절리는 불규칙적이기는 하지만 $N10^{\circ}{\sim}60^{\circ}E$, $70^{\circ}SE$ 내지 수직이 우세하다. 탄성파 탐사결과에 의하면, 본조사지역 동반부에 남북방향의 저속도대가 발달하고 있음을 확인하였으며, 지층별 추정탄성파속도를 요약하면 표토층, 200~800m/sec; 상부풍화대 500~1000 m/sec; 하부풍화대와 연암, 1000~3000 m/sec; 경암, 3000m/sec 이상이다. 시추결과에 따르면, 안산암은 매우강하고, 치밀하고, 암심회수율과 RQD는 거의 100%에 달하고 있었다. 섬장암의 분포지역은 절리가 발달해 있었고, 55~63m (DH-2 hole) 구간에 특히 발달되어 있었다. 수압시험은 double packer를 이용하여, 공저에서 부터 매 2m 간격으로 $5kg/cm^2$와 $10kg/cm^2$의 압력으로 수압시험을 실시하였으며, 누수현상이 일어나는 구간은 $5kg/cm^2$ 이하의 압력으로 실시하여 매구간별 투수계수를 구했다. DH-1 hole의 경우 자연수위는 지표하 9m였고, 38~40m 까지는 투수계수가 $3.77{\times}10^{-4}{\sim}6.44{\times}10^{-4}cm/sec$에 이르며 48~70m 구간까지는 $10kg/cm^2$의 수압하에서 전혀 누수현상이 발생하지 않았으며, 매우 견고한 암석임을 임시하고 있다. DH-2 hole 의 경우, 파쇄 및 년층작용으로 본구간의 투수계수는 $1.86{\times}10^{-4}{\sim}2.5{\times}10^{-4}cm/sec$를 나타내고 있다. 현재까지 조사된 결과로 보면, 서반부에 발달한 계곡을 따라 선장암체가 심히교란되어, 본지역을 피하여 지하비축 구조물이 설치되어야 할것으로 사료된다.

• 자원환경지질
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• 제10권1호
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• pp.37-48
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• 1977

The earth's crust is unceasingly undergoing deformations because of the forces acting upon it. The relationship between the tectonic forces and the resulting deformations are found from the states of stresses in the earth's crust induced by these forces. The study has been attempted to analyze the deformations of the overlying sedimentary layers, which are deformed by the magma intrusion along its lower boundary. The elastic model is constructed to analyze the geologic structures, by means of the theory of elasticity, and then the appropriate boundary conditions are given. The solution of the Airy stress function which satisfies the given boundary conditions is derived from the analytic method. The internal stress distributions of the deformed elastic model layer are portrayed by principal stress trajetories, and then the corresponding potential faults and joints systems are predicted from the Coulomb-Mohr failure criterion. The internal displacement distributions are shown by the calculated displacement components vectors, namely horizontal, vertical and net components. Results of the numerical calculations show the developments of some geologic structures as follows; (1) one set of shear joints and or two sets of shear joints which are oppisite directions, and one set of extension joints parallel to the ${\sigma}_1$ direction, (2) one set of high angle thrusts and normal faults, (3) symmetric fold; both limbs are dipping in opposite direction with low angle. The field work at the Wall-A San area, located near Jinju City, in southern Korea, had accomplished to compare the field structures with the predicted ones. The results of the comparison exhibits the developments of joint and fault systems satisfactorily consistent with each others. But the area does not show any type of folding, in spite of the intrusion of a granodiorite massif, this fact is one of the important features of the whole Kyungsang sedimentary basins of Mesozoic age distributed at the south-eastern parts of Korea. For this reason, it is thought that the magma intrusion had occurred with extremly low pressure. The geologic structures have been modified by the erosion and weathering throughout the geologic time, and the conditions of the sedimentary layers (width, thickness and radius of magma) are not the same as before, being intruded by the magma. To enlighten this, it is preferable to study these geologic structures with analyses of various types of rheological models.

• 항공우주시스템공학회지
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• 제14권1호
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• pp.68-73
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• 2020

본 논문은 산악 지형, 도심, 함정, 교량 등에서 수직 이·착륙 비행, 제자리 비행, 고정익기처럼 저속 및 고속비행을 할 수 있는 덕티드 추진체를 사용한 수직 이·착륙 초소형 무인 항공기 개발 동향을 기술한다. 이 항공기는 여러 측면에서 헬리콥터와 고정익기와는 비행 특성이 다르다. 미육군 미래 전투 체계와 DARPA의 OAV 프로그램의 목적은 운용자에 안전하고 낮은 음향 특성을 갖는 수직 이·착륙 덕티드 팬 초소형 무인 항공기 개발이다. 현재의 초소형 무인 항공기에 영상/적외선 카메라를 탑재하고 숲이나 언덕 뒤에 숨어 있는 적을 정지비행과 응시로 약 1 시간 동안 감시 및 정찰을 한다. OAV의 Class-I은 개인 병사가 배낭에 담아 운반할 수 있는 크기와 무게의 수직 이·착륙 덕티드 MAV 개발이다. Class-II는 Class-I보다 두 배의 운용 시간과 더 넓은 범위의 비행이 가능한 유기체의 수직 이·착륙 덕티드 팬 초소형 무인 항공기 개발이다. 초소형 무인기는 장시간 운용을 위해 현재의 '호버 및 응시'에서 '퍼치-앤-응시'으로 기술을 발전시켜야 한다. 근 미래의 OAV 개념은 유·무인 지상 차량이 주행하는 동안에 차량의 상부에 자동 이착륙하고, 탑재된 상태로 이동하고, 재급유, 재충전, 재이륙하는 합동 운용으로 임무 능력과 효율성을 확장하는 것이다. 덕티드 MAV는 지상 차량의 착륙 패드에서 자동으로 이착륙하기 위해 저렴한 초소형 GPS를 활용한 고정밀 상대 위치 기술 개발이 필요하다. 또한, VTOL 덕티드 MAV와 유·무인 지상 차량 간에 유기체의 협업 동작이 가능케하는 공통 명령과 제어 아키텍처를 개발할 필요가 있다.

• 한국음향학회지
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• 제34권6호
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• pp.411-422
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• 2015

본 논문은 "천해 지질환경과 음파전달환경과 상호 연계 연구"를 목적으로 한국해양과학기술원과 한양대학교가 2013년 4 ~ 5월에 경기만 태안반도 서쪽에 위치한 천해환경에서 공동으로 수행한 지질환경 조사 및 수중음향 실험에 대한 개요를 기술하였다. 실험지역은 강한 조류와 천해의 지형학적 특성에 의해 다양한 종류의 퇴적상과 베드폼이 형성되는 해역이다. 집중적인 지질환경 특성 조사를 위해 다중음향측심기, 천부지층탐사기, 중천부지층탐사기, 그랩을 이용하여 조사해역의 지질환경 특성을 파악하였으며, 저주파수, 중주파수 대역의 음원과 수직선배열청음기를 이용하여 주파수 200 ~ 16,000 Hz 대역에서 1) 저주파수 음파전달, 2) 중주파수 해저면 반사손실, 3) 주변소음의 공간 코히런스 분석, 4) 중주파수 해저면 후방산란에 대한 연구 주제로 해상실험이 수행되었다. 본 논문에서는 연구지역에서 음향실험을 실시한 동기, 음향실험 방법론과 측정된 지질자료를 기반으로 음향자료 해석과, 실험기간 동안 측정된 지질환경, 기상 해양물리 자료를 요약 정리하여 기술하였다.

• 대한관절경학회지
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• 제16권1호
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• pp.9-16
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• 2012

목적: 경골 고평부 골절은 슬관절에 다양한 문제를 발생시킨다. 본 연구는 관절경하 경골 고평부 골절에서 반월상 연골 손상 양상을 확인하고자 한다. 대상 및 방법: 2007년 3월부터 2010년 3월까지 경골 고평부 골절을 진단 받은 39명의 환자 중 33명 환자를 대상으로 골절 고정 시내 관절경을 시행하였다. Schatzker 분류에 따르면 1명의 I형(3.3%), 19명의 II형(53.3%), 4명의 III형(13.3%), 2명의 IV형(6.6%), 2명의 V형(6.6%), 5명의 VI형(20%) 소견을 보였다. 결과: 25명의 환자(75.8%)에서 외측 반월상 연골 파열 소견을 보였다. Schatzker II형 환자 19명 중 18명의 환자(94.7%)가, Schatzker III형 환자 4명 중 3명의 환자(75%)가, Schatzker VI형 환자 5명 중 4명의 환자(80%)가 반월상 연골 파열 소견을 보였다. 반월상 연골 중 가장 많이 손상된 부분은 외측 연골의 전각부분이다(22/25). 25명의 반월상 연골 파열 환자 중, 한 명을 제외한 모든 환자에서 반월상 연골 변연부 수직 종파열 양상을 보였으며, 이는 대부분의 경우에 있어 관절경하 봉합술을 시도할 수 있었다. 결론: 경골 고평부 골절에 있어 관절경하 반월상 연골 손상에 대한 파악 및 치료에 유용하며, 경골 고평부 골절환자에서 관절경을 권한다.

• 수산해양기술연구
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• 제37권2호
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• pp.78-84
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• 2001

1999년 5월 29일부터 6월 30일까지의 남해안에서의 수심에 따른 수중광의 변화와 조업시간의 경과에 따른 예망 상대유속을 측정하고, 권현망어구에 대한 체장 4~7cm정도 되는 멸치들의 도피 반응행동을 관찰하고 분석한 결과는 다음과 같다. 1) 남해안 통영, 거제 부근 멸치어장에서 수심에 대한 수중광의 변화를 자연대수 곡선식으로 나타내면 광흡수 계수 c는 대표적인 관측점에서 주로 0.24~1.03 범위로 나타나서, 멸치의 어구에 대한 시인도가 어장에 따라 클 것으로 보인다. 2) 권현망어구의 원형그물과 1/2축소그물의 자루그물 입구부분의 상대유속을 기준으로 할때, 수비와 자루의 연결부분의 유속비는 평균 1.46, 자루부분의 유속비는 평균 0.67로 나타나서, 어구의 부위에 따른 상대유속변화가 멸치의 유영운동과 도피운동에 영향을 줄 것으로 보인다. 축소된 권형망어구에 있어서의 멸치의 대망행동을 관찰한 결과 수비와 자루연결부분에서 빠져나가는 1분당 멸치도피수는 평균 455미 정도였으며, 자루의 앞에서 예인방향으로 유영하는 깔대기를 빠져나가는 1분당 멸치도피 수는 평균 308미 정도로 나타나서, 어구 전체적으로는 상당수의 멸치들이 능동적인 도피행동을 나타내는 것으로 추측된다.