• Title/Summary/Keyword: pillars

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An Automatic Transfer System of the Path for an Unmanned Machine in the Greenhouse (온실내 무인작업기를 위한 경로 자동변환 시스템 개발)

  • 김창수;이대원;이승기
    • Journal of Bio-Environment Control
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    • v.9 no.4
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    • pp.237-243
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    • 2000
  • Agricultural machine is currently operated by man power in the greenhouse, which is oppressively hot and humid, and is for a farmer not to work in comfortable circumstances. In the future, agricultural machine will not have to operate by man power, but it will need do by unmanned power. In order to put into the automatic and unmanned operation of agricultural machine, this system was designed and built to move through the fixed path in the greenhouse. This system was composed of guiders(wires), a limit switch, an operating equipment, its software for automatizing a machine in the greenhouse. The guider was connected between the wall pillars, and the equipment was able to slide over the fixed path made of the guider, by rectilinear and rotational motion. A micro mouse was developed with a stepping motor to calculate on the success rate of its operation with the system As might be expected, this system with the micro mouse was moved the moved the paths with a success rate of 100% on the flat plane surface in our laboratory. However, on the sand plane or the other materials plane, the success rate was not better than 80%. If the micro mouse were well operated, the success rate was would be 100%. Based on the results of this research, this system would be expected to operate well on the path made of a simple wire.

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A Study on the FIDIC Conditions of Contract for Design, Build and Operate Projects (FIDIC의 DBO 프로젝트용 표준계약조건에 관한 연구)

  • Choi, Myung-Kook
    • THE INTERNATIONAL COMMERCE & LAW REVIEW
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    • v.46
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    • pp.29-60
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    • 2010
  • The incentive and reasons to publish FIDIC Conditions of Contract for Design, Build and Operate Projects(DBO Form) are manifold. It is partly a response to the increasing need for sophisticated project delivery methods in both the public and private sectors and the already widespread use of the FIDIC Yellow Book with operation and maintenance obligations and partly a response to the challenge to decrease maintenance cost to a minimum by means of a new procurement route. As a result, FIDIC has developed a new model form to meet this market place requirement. On the other hand, FIDIC did not simply adapt the Yellow Book but has developed a new form from it, whilst preserving the style of the already known FIDIC Forms and maintaining the wording where it was not necessary to change it for the purposes of a DBO Form. Moreover DBO Form fills up supposed gaps in other FIDIC Forms and ameliorates the claim management and dispute management framework. FIDIC DBO approach may be shortly summarized as follows. First, DBO Form provides for single project responsibility. Second, DBO Form has the clear objective of ensuring the use of a most reliable and efficient technology at the lowest life-cycle cost. Third, DBO Form is intended to operate as an effective quality increase in the design and construction of projects. Fourth, DBO Form is intended to provide significant benefits with regard to system integration and reduction of risks. Fifth, DBO Form accelerates and enhances completion schedule compliance. Sixth, DBO takes care of all three supporting pillars of sustainability(including economical, environmental and social elements). DBO Form is obviously a good starting point for negotiations and the preparation of calls for tenders, thus saving the parties time and money. However, existing cultural and legal differences, particular local conditions and the particular needs of some branches of the industry may require the form to be adapted according to the particular needs of a project. And Civil law practitioners are strongly recommended to verify carefully the underlying legal concepts and background of each clause of the General Conditions in order to avoid unnecessary and sometimes unnatural changes and amendments being made. Note that when preparing the Particular Conditions ensure that terminology is consistent and that existing inherent concepts should not be ignored.

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Species Identification of Wooden Elements Used for Daewungjeon Hall in the Bukjijangsa Temple, Daegu, Korea (대구 북지장사 대웅전 목부재의 수종 식별)

  • Yeon, Jung-A;Park, Won-Kyu
    • Journal of the Korean Wood Science and Technology
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    • v.41 no.3
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    • pp.201-210
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    • 2013
  • The purpose of this study was to examine the species of 117 wooden elements which were used in the Daewungjeon Hall (National Treasure No. 805, constructed in A. D. 1659) of Bukjijangsa Temple, Daegu, Korea. Pillars were identified as 5 red pines (hard pines; most likely, Pinus densiflora S. et Z.), 2 Cerris section of subgenus Lepidobalanus (deciduous oaks) and 3 Tsuga spp. Hwalju columns were 3 Abies spp. and 1 red pine. Head-penetrating ties were 8 red pines and 1 Cerris sp.; Pyeongbang, 3 red pines and 6 Cerris spp. Purlins were identified as 17 red pines, 16 Cerris spp. and 1 Tsuga sp. Angle rafters were 3 red pines and 1 Cerris sp., and end angle rafters, 2 red pines, 1 Zelkova serrata and 1 exotic hard pine. All of brackets (31 woods), jangyeo (4) and deot-chunyeo (2) were identified as red pines. As a whole, red pines (70.1%) and Cerris (22.2%) were major species used in the Daewungjeon Hall of Bukjijangsa Temple. Tsuga, Abies and exotic hard pines seem imported woods used for recent repairs.

Analysis of PLAN Modernization Trend and Prospects for Balance of U.S-China Naval power in the East Asia (중국해군(PLAN)의 현대화 추세와 동아시아 지역의 미·중 해군력 균형 전망)

  • Kwon, Jeong Wook
    • Strategy21
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    • s.43
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    • pp.5-28
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    • 2018
  • The tensions between the U.S and China, which form the two pillars of the G2 era, seem to have persisted even after the Trump administration inaugurated. The strong confrontation between the two in recent foreign security issues may drive to develop an inadvertent military conflict, and it is high likely to occur in the maritime are. The purpose of this study is not only to analyze the balance of modernized naval forces in the PLAN through naval strategy changes and weapons system modernization trend, but also to predict the impact of the geographical proximity difference on the balance of naval forces in the disputed areas. It examined the impact of distance and geography on naval power by assessing the modernization pattern of the PLAN and capabilities in the context of two scenarios at different distances from China by 2020: one centered on Taiwan and the other on the Spratly Islands. The PLAN's strategy had impact on operational concept and forces construction. First, from the viewpoint of operation operational concept, it can be seen that the passive defense is changing into active defense. Second, in terms of power construction, it can threaten the surface and submarines of U.S power from a distance. And they generated follow three features; The ocean is not the focus of Chinese submarines, Horizontal and vertical expansion of Chinese naval vessels, The improvement of the suppression ability as the Chinese naval modernization ratio increases. The strength of the PLAN is dominant over the U.S in terms of reserves, and it can complement the qualitative deterioration by utilizing nearby bases in the vicinity of the mainland, such as the Taiwan Strait. However, due to the shortage of aircraft carriers, there is a possibility that it will take some time to secure the advantage of air and ocean in the amphibious operation. Therefore, as the dispute is prolonged, China may fail to achieve its original goal. In addition, the lack of cutting edge Commanding Ships may bring to weaken the C2 capabilities. At results, it is expected that PLAN will not be able to have a superiority in the short term due to lagging behind U.S advanced technology. Nevertheless, PLAN has strengthened its naval power through modernization sufficiently and it is highly likely to use force. Especially, it is more likely in the region where the naval power operation like the Taiwan Strait is possible with the almost equality to that of the United States. China will continue to use its naval forces to achieve a rapid and decisive victory over U.S in the close area from the land.

A Study on the Size of the Stone Pillars(A Statue of confucian Official and A Statue of Military Officer) in the Royal Tomb of the Joseon Dynasty (조선시대 왕릉 석인상(문인석, 무인석)의 크기에 관한 연구)

  • Kim, Jin-Myung;Choi, Tae-Wol;Lee, Yong-Sun
    • Industry Promotion Research
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    • v.5 no.2
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    • pp.27-32
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    • 2020
  • This study is a study on the size of the stone statues of the royal tombs in the Joseon Dynasty. In summary, the size of the stone statues of Moon, Inseok and Unmanned Stone increased in the 1600s and then decreased slightly in the 1700s, but increased in size in the 1800s. It was confirmed that the average analysis result. The statue of Seok-in of the Royal Tombs of the Joseon Dynasty reflects the characters of the time, and through this, the typical figures of the times can be examined. The royal tomb has consistency and uniqueness, and the norms regarding the size of stone statues have changed over time. As a building of the authoritative symbol of the ruling class, it was a national construction where royal tombs were built according to rituals and laws. It is said that the size of the stone statues in the Joseon Dynasty was about 90cm smaller than the stone statues of the tombs. In this study, the significance of this study is to confirm the stone size of each stone age in the royal tomb of Joseon.

Flip Chip Process by Using the Cu-Sn-Cu Sandwich Joint Structure of the Cu Pillar Bumps (Cu pillar 범프의 Cu-Sn-Cu 샌드위치 접속구조를 이용한 플립칩 공정)

  • Choi, Jung-Yeol;Oh, Tae-Sung
    • Journal of the Microelectronics and Packaging Society
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    • v.16 no.4
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    • pp.9-15
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    • 2009
  • Compared to the flip-chip process using solder bumps, Cu pillar bump technology can accomplish much finer pitch without compromising stand-off height. Flip-chip process with Cu pillar bumps can also be utilized in radio-frequency packages where large gap between a chip and a substrate as well as fine pitch interconnection is required. In this study, Cu pillars with and without Sn caps were electrodeposited and flip-chip-bonded together to form the Cu-Sn-Cu sandwiched joints. Contact resistances and die shear forces of the Cu-Sn-Cu sandwiched joints were evaluated with variation of the height of the Sn cap electrodeposited on the Cu pillar bump. The Cu-Sn-Cu sandwiched joints, formed with Cu pillar bumps of $25-{\mu}m$ diameter and $20-{\mu}m$ height, exhibited the gap distance of $44{\mu}m$ between the chip and the substrate and the average contact resistance of $14\;m{\Omega}$/bump without depending on the Sn cap height between 10 to $25\;{\mu}m$.

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Analysis and Proposal of Startup Policy: Focusing on step-by-step Implications such as Startup, Growth, and Recovery (스타트업관련 정책의 현황분석과 정책제안: 창업, 성장, 회수 등 단계별 시사점을 중심으로)

  • Joe, Byoung-Moon;Shin, Hyun-Han
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.15 no.2
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    • pp.97-110
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    • 2020
  • This paper is on the policy proposal for venture ecosystem. First, one of the three secrets of the US venture ecosystem is the law of 50:50. Angel capital investment is as important as venture capital investment. Although professional angel investors and accelerators account for as much as VC in the venture ecosystem, they are ignored from policy considerations. We argue that the revision of related law is urgent. Second, large US firms invest more in M&As than in internal R&D. Therefore, accelerators and professional angel investors could make effective investment recovery after investing in a startup company. In other words, angel capital does not come in without secondary market development. Angel capital and secondary markets are the two pillars of the venture ecosystem. The government alone is difficult to develop a secondary market. This is why the private sector should come in and introduce corporate venture capital (CVC). Third, we believe the policy direction for national economic growth should be extended from the startup to scale-up. This is because the startup's sales and job creation will start in five years. While the previous study focused on funding (venture financing), this paper aims to balance all three stages of a venture: startup, growth, and recovery, which are the life cycle of a venture company or venture investment. In particular, we propose specific policies in each chapter to improve practical application.

A study on the Characteristics of Structural Proportion of Pillar and 'Kong-po' in 'Main Hall of Royal Palace(正殿)' of the Royal Palace (궁궐(宮闕) 정전(正殿)에서 기둥과 공포의 구조적(構造的) 비례특성(比例特性)에 관한 연구(硏究))

  • Park, Eon-Kon;Choi, Hyo-Sik
    • Journal of architectural history
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    • v.14 no.1 s.41
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    • pp.71-87
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    • 2005
  • 4 royal palaces are currently remained from capital city (Seoul) of 'Cho-Sun(朝鮮)' period. In these palaces, 'Main hall of Royal Palace(正殿)' is the center of the Royal Palaces. The 'Main hall of Royal Palace' of the Royal Palace was the best building of that time. Therefore there were many studies about the 'Main hall of Royal Palace'. But these studies were individual studies of these 'Main hall of Royal Palace'. Therefore, this study is to analyze and compare 4 'Main hall of Royal Palace' of the Royal palaces. It is to study the proportion regarding the Diameter of the pillar, the Height, the pillar and pillar Interval's Distance, and the arrangement of 'Kong-Po(bracket sets)'. With these studies, it is to prove that the 'Main hall of Royal Palace' is the building which high construction technique of this time is expressed. Result of this study is as followings; First, the proportion of pillar height(H) to its diameter(D) average from H=8.0 to 8.5D. Only the Myeong-Jeong-Jeon omitted the 'Go-Ju(高柱)' in the 'Toi-Kan (退間)' to place Ea-Jwa(御座). Second, Second, the proportion of diameter of the pillar of 'Eoi-Bu-Pyeong-Ju(外部平柱)' and 'Nae-Jin-Go-Ju(內陣高柱)' average D1(Diameter of 'Eoi-Bu-Pyeong-Ju') =0.91D2 (Diameter of 'Nae-Jin-Go-Ju'). In regards to the height, the single floor 'Main hall of Royal Palace' and double floor 'Main hall of Royal Palace' seems to be different. The height proportion of the double floor 'Main hall of royal palace' is H1(Height of 'Eoi-Bu-Pyeong-Ju')=0.34H2(Height of 'Nae-Jin-Go-Ju') and single floor 'Main hall of Royal Palace' has a proportion of H1=0.62H2. Third, in Geun-Jeong-Jeon, with the proportion of height and diameter of the pillar, interval's distance between pillars and diameter, the pillar interval distance and height, of 'Ea-kan(御間)' from the 'Toi-Kan' is different from 'Main hall of Royal Palace'. This is because the structure of 'Toi-Kan' of Geun-Jeong-Jeon is not stable. In order to reinforce this, 'Gui-Go-Ju(隅高柱)' of the Geun-Jeong-Jeon jut out $4{\sim}7%$ more compared to In-Jeong-Jeon. Fourth, when comparing double floor 'Main hall of royal palace' of Geun-Jeong-Jeon and In-Jeong-Jeon, based on distance of 'Eoi-Bu-Pyeong-Ju' and 'Nae-Jin-Go-Ju' of lower level, the 'Sang-Bu-Pyeong-Ju(上部平柱)' of Geun-Jeong-Jeon jut out $4{\sim}7%$ more compared to the In-Jeong-Jeon and also It becomes thicker. Fifth, the arrangement of 'Kong-Po' on the front row of 'Gan(間)' had to do with the change of side 'Gan'. Even though the Geun-Jeong-Jeon and the In-Jeong-Jeon were double floors, the arrangement of the 'Kong-Po' is different because the number of side bay is different.

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Effect of Separation Between Main and Divergent Tunnels in Divergence Section of Double-Deck Tunnel on the Stability (복층터널 분기구에서의 터널 이격에 따른 안정성 영향)

  • La, You-Sung;Kim, Bum-Joo
    • Journal of the Korean Geosynthetics Society
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    • v.15 no.2
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    • pp.45-54
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    • 2016
  • Double deck tunnels are considered to have a large demand in a near future for solving traffic congestion problems and overcoming the limitations in constructing new tunnels. This study presents a numerical investigation using finite element (FE) analysis on the behaviors of the tunnels and the stability of pillars in a divergence section where single tunnel is diverged from a main line double deck tunnel. The effects of the separation distance between the diverged and the main tunnels and the ground condition were examined through the FE analysis by varying the separation distance from 0.1D to 2.0D (D: diameter of main tunnel) and the rock class from class I to V, respectively, and the analysis results were compared with those using empirical methods, strength-stress ratio, and the volume of interference. The FE analysis results indicated that the separation distance has a larger effect on tunnel behaviors, compared with the rock strength, and a single tunnel with a large cross section is more favorable than two separated tunnels for tunnel stability when the separation distance is below 0.7D.

A numerical study of pillar reinforcing effect in underground cavern underneath existing structures (지하공간하부 지하저류공동에서의 필라 보강효과에 관한 수치해석적 연구)

  • Seo, Hyung-Joon;Lee, Kang-Hyun;Han, Shin-In;Lee, In-Mo
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.14 no.5
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    • pp.453-467
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    • 2012
  • Usage of underground space is increasing at metropolitan city. More than 90% of flood damages have occurred at downtown of metropolitan cities. In order to prevent and/or minimize the flood-induced damage, an underground rainwater detention cavern was proposed to be built underneath existing structures. As for underground caverns to be built for flood control, multi-caverns will be mostly adopted rather than one giant cavern because of stability problem. Because of the stress concentration occurring in the pillars between two adjacent caverns, the pillar-stability is the Achilles' heel in multi-caverns. So, a new pillar-reinforcing technology was proposed in this paper for securing the pillar-stability. In the new pillar-reinforcing technology, reinforced materials which are composed of a steel bar and PC strands are used by applying pressurized grouting, and then, by applying the pre-stress to the PC strands and anchor body. Therefore, this new technology has an advantage of utilizing most of the strength that the in-situ ground can exert, and not much relying on the pre-cast concrete structure. The main effect of the pressurized grouting is the increase of the ground strength and more importantly the decrease of stress concentration in the pillar; that of the pre-stress is the increase of the ground strength due to the increase of the internal pressure. In this paper, ground reinforcing effects were verified the stress change in pillar is obtained by numerical analysis at each construction stage. From these results, the effects of pressurized grouting and pre-stress are verified.