• Title/Summary/Keyword: opening shape

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Restoration of Pottery and Celadon for Exhibition (展示(전시)를 위한 토기(土器)와 청자(靑磁)의 복원(復元) - 토기기대(土器器臺), 노형기대(爐形器臺), 청자사이호(靑磁四耳壺)를 중심(中心)으로 -)

  • Kang, Hee-suk;Ahn, Byong-chan
    • Conservation Science in Museum
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    • v.1
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    • pp.37-42
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    • 1999
  • Conservation treatment was done for the pottery-stand of Kaya period which was to be exhibited in celebration of the opening of Kimhae National Museum and for the jar of Chinese celadon which was to be exhibited in Korea National Museum's special exhibition "Formation of Ancient States". Through the examinations by naked eyes and under the microscope, condition before treatment, patterns and manufacturing techniques of the objects were observed. According to these examinations, conservation treatments, suitable for each object was finished. As the pottery-stand was damaged severely, the epoxy resin was pasted directly on the broken surface of the pottery to restore the original shape and pattern, color and feeling similar to original state were given to the restored area. Although same restoration material was applied on the celadon, it was not pasted directly on the broken surface of the celadon so that the restored area could be dismantled, and color and feeling were also treated somewhat differently.

As tudy on the underwater stability according to the composition of the sea anchor (씨앵커의 구성에 따른 수중 안정성에 관한 연구)

  • Jung-Mo, JUNG;Hyung-Seok, KIM
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.58 no.4
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    • pp.289-298
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    • 2022
  • Sea anchor for fishery is commonly used in jigging fishery and purse seine. The study of sea anchor was studied for improvement of opening efficiency and drag by changing the type of shape and the diameter of vent. However, standard specification of sea anchor is not set and has not been studied for underwater stability. Therefore, this study aimed to improve underwater stability of sea anchor by changing a vent diameter and weight of sinker. The experiment was conducted in flume water tank. The experiment model of sea anchor was made from actual model of sea anchor which is used in fishery by similarity law. The model of sea anchor was designed to different types of vent diameter and weight of sinker in different current speed. The value of movement of side to side (X-axis), drag of sea anchor (Y-axis) and movement of up and down (Z-axis) was measured for 30 seconds. Each value of X, Y, Z-axis was analyzed through t-test and ANOVA analysis to verify that each value had a significant difference according to the difference compositions. There was correlation between the movement of X-axis and Z-axis. The drag of sea anchor was stronger as the current speed increased. However, the larger the vent diameter, the weaker the drag. From the result of the standard deviation, the movement of X-axis was inversely proportional to the vent diameter. However, movement of Z-axis was larger as the weight of sinker was the heaviest or lightest from the result of the standard deviation. These results suggest that the sea anchor should be combined with proper size of the vent diameter and the weight of sinker to improve the stability.

User Perception of Ai Self-Organizing Natural Image Generation Analyzed by Cognitive Paradigm

  • Soo-Jin Lee
    • International Journal of Advanced Culture Technology
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    • v.12 no.3
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    • pp.67-72
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    • 2024
  • The algorithm is applied on the premise that the image generated by AI can be recognized and used smoothly by the user. Other assets are not exposed to the user or discarded because they are unnecessary or unfamiliar. This study aims to expand the scope of the utility of the image generated by AI, which is used as a high-level tool in the design field. To this end, we first examined human information processing and reflection in AI by the cognitive paradigm by examining previous studies and cases, and discussed the value of expansion by focusing on creativity and bottom-up processing of AI's self-organization. Considering the human recogmition process that instinctively grasps an object, the following AI usability was proposed. It is to utilize AI as a high-level tool applied appropriately to human perception, or to utilize the derivative itself by bottom-up self-organization. In addition, it is to set the algorithm to the minimum intervention so that basic elements such as shape, color, size, texture, and movement are composed of figure-ground according to the human perception process that instinctively grasps an object, and to utilize the results. Limiting the use of AI to a tool suitable for human perception and information processing or production by designers or general users is to operate only a part of the convenience and usability of AI. The image creation through AI's self-organization, as seen from the cognitive paradigm, is a step toward opening a new era of design where technical aesthetics meets devices, just as design has been constantly developing in pursuit of novelty and differentiation due to its nature.

Egg Development and Early Life History of Zacco koreanus (Pisces: Cyprinidae) (참갈겨니 Zacco koreanus (Pisces: Cyprinidae)의 난 발생과 초기생활사)

  • Lee, Wan-Ok;Kim, Kyeong-Hwan;Back, Jae-Min;Song, Mi-Young
    • Korean Journal of Ichthyology
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    • v.25 no.4
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    • pp.200-207
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    • 2013
  • We investigated developmental stages of egg and early life history of the Korean indigenous fish, Korean Chub Zacco koreanus from the South Han River in 2011 for phylogenetic study and conservation of this species. Eggs of Zacco koreanus were artificially fertilized by the dry method in the laboratory. The fertilized eggs were demersal, almost spherical in shape, transparent and unpigmented, with a pale yellow yolk, and no oil globule and average $3.09{\pm}0.07$ mm (n=10) in diameter. The hatching of the embryo took place in about 68 hrs after fertilization under water temperature of $20.0{\sim}23.0^{\circ}C$ and the newly hatched larvae were average $10.30{\pm}0.40$ mm (n=10) in total length (TL). Six days after hatching, the larvae grew up to $16.12{\pm}0.42$ mm (n=8) in TL and york sac absorption, mouth and anus opening were shown postflexion larvae stage. 17 days after hatching, most of fin-rays appeared at $18.21{\pm}0.38$ mm (n=6) in TL and brown spot appeared on the abdomen. 27 days after hatching, the larvae were brought up to $20.01{\pm}1.12$ mm(n=5) in TL and all their fin-rays were formed. 120 days after hatching, the larvae (juvenile) were $23.29{\pm}3.12$ mm (n=10) in TL and their body shape and color pattern were similar to the adult fish.

Characteristic of Wave Diffraction and Reflection for Irregular Waves in SWASH Model Around Small Port Structures (소규모 항만 구조물 주변에서 불규칙파에 대한 SWASH 모형의 반사 및 회절)

  • Kwon, Kyong Hwan;Park, Chang Wook;Park, Il Heum;Kim, Jong Hoon
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.31 no.6
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    • pp.468-477
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    • 2019
  • The numerical model of Boussinesq approximation, which is mainly used for evaluating the port calmness due to the irregular waves, has a limit of applicability of lattice size in ports such as marinas with narrow port openings of around 30m. The SWASH model controls the partial reflection according to the depth, porosity coefficient and structure size when applying the reflected wave incident on the structure and terrain. In this study, the partial reflection evaluation at the front of the structure according to the bottom shape and the shape of the structure are examined. In order to evaluate the reproducibility of the model due to the diffraction waves entering the term, the area of incidence at right angles and inclination of the structure is constructed and compared with the diffraction theory suggested by Goda et al. (1978). The experimental results of the sectional structure reflectances calculated as the depth mean show reflectances similar to the approximate values of the reflectances presented by Stelling and Ahrens (1981). It is considered that the reflected wave is well reproduced according to the control of the reflected wave at the boundary and the shape and topography of the structure. Compared with previous studies to examine the diffraction of the wave incident from the breakwater opening, the wave incidence angle and the shape of the diffraction wave are very similar to the theoretical values, but both oblique and rectangular incidence In the case where the direction concentration is small, the diffraction degree is underestimated in some sections with the crest ratio of 0.5 to 0.6.

Mechanical and Operational Factors Affecting the Efficiency of Rice Polishing Machines (정미기의 능률에 미치는 기계적 요인및 작동조건에 관한 연구)

  • No, Sang-Ha
    • Journal of Biosystems Engineering
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    • v.1 no.1
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    • pp.15-15
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    • 1976
  • In analyzing the operational characteristics of a rice whitening machine, the internal radial pressure of the machine was measured using strain gage equipment. Changes in cylinder and feed screw configurations, screen type, cylinder speed and counter-pressure levels were examined to determine their impact on the quality and quantity of milled rice and the performance of the machine. The results are summarized as follows: 1. The internal radial pressure in the whitening chamber varied with the surface condition of the grain being processed. During the first or second pass through the machine, pressure was relatively low, reached a maximum after two to three passes with combinations I and II, three to six with combination III and then began to fall. 2. The pitch of the feed screw and the size of the feed gate opening which determine the rate of entry of grain into the whitening chamber, appeared to be the most important factor aff-::cting the degree of radial pressure, quality and quantity of milled rice and the efficiency of the machine. Using a feed screw with a wide pitch (4.8cm), radial pressure was relatively high and head rice recovery ratio \vere quite low. In this case capacity and machine effic?iency were much higher than obtained when using a feed screw with a narrow pitch (2.3cm). Very significant responses in radial pressure, head rice recovery rates and machine capacity were observed with changes in cylinder speed and counter-pressure levels when using the wide pitch feed screw. 3. The characteristics of the screen which surrounds the whitening chamber had an important effect on whitening efficiency. The existence of small protuberances on the original screen resulted in significant increases in both machine capacity and efficiency but without a significant decrease in head rice recovery or development of excessive radial pressure. Further work is required to determine the effects of screen surface conditions and the shape of the cylinderical steel roller on the rate of bran removal, machine efficiency and recovery rates. The size of the slotted perforations 0:1 the screen affects total milled rice recovery. The opening size on the original screen was fabricated to accommodate the round shape of Japonica rice varieties but was not suitable for the more slender Indica type. Milling Indica varieties with this screen resulted in a reduction in total milled rice recovery. 4. An increase in cylinder speed from 380 to 820 rpm produced a positive effect on head rice recovery for all machine combinations at every level of counter-pressure used in the tests. Head rice recovery was considerably lower at 380rpm using a wide screw pitch when compared to the results obtained at speeds from 600 to 820 r.p.m. The effects of cylinder speed On radial pressure, capacity and machine efficiency showed contrasting results, depending on the width of the feed screw pitch. With a narrow feed screw pitch (2.3cm), a direct proportional relationship was observed bet?ween cylinder speed and both radial pressure and machine efficiency. In contrast, using a 4.8 centimeter pitch feed roller produced a series of inverse relationships between the above variables. Based on the results of this study it is recommended when milling Indica type long grain rice varieties that the cylinder speed of the original machine be increased from 500-600 rmp up to a minimum of 800 rpm to obtain a greater abrasive effect between the grain and the screen. The pitch of the feed screw should be also reduced to decr?ease the level of internal radial pressure and to obtain higher machine efficiency and increased quality of milled rice with increased cylinder speeds. Further study on the interaction between cylinder speed and feed screw pitch is recommended. 5. An increase in the counter pressure level produced a negative effect On the head rice recovery with an increase in radial pressure, capacity, and machine efficiency over all combinations and at every level of cylinder speed. 6. Head rice recovery rates were conditioned primarily by the pressure inside the whitening chamber. According to the empirical cha racteristics curve developed in this study, the relationships of head rice recovery ($Y_h$) and machine capacity ($Y_c$/TEX>) to internal radial pressure ($X_p$) followed an inverse quadratic function and a linear function respectively: $$Y_h^\Delta=\frac{1}{{1.4383-0.2951X_p^\ast+0.1425X_p^{\ast\ast}}^2} , (R^2=0.98)$$$$Y_c^\Delta=-305.83+374.37X_p^{\ast\ast}, (R^2=0.88)$$The correlation between capacity and power consumption per unit of brown rice expressed in the following exponential function: $$Y_c^\Delta=1.63Y_c^{-0.7786^\{\ast\ast}, (R^2=0.94)$$These relationships indicate that when radial pressure increases above a certain range (1. 6 to 2.0 kg/$cm^2$ based On the results of the experiment) head ricerecovery decrea?ses in a quadratic relation with a inear increase in capacity but without any decrease in power consump tion per unit of brown rice. On the other hand, if radial pressure is below the range shown above, power consumption increases dramatically with a lin?ear decrease in capacity but without significant increases in head rice recovery. During the operation of a given whitening machine, the optimum radial pressure range or the correct capacity range should be selected by controlling the feed rate and/or counter-pressure keeping in mind the condition of the grain, particulary the hardness. It was observed that the total number of passes is related to radial pessure level, feed rate and counter-pressure level. The higher theradial pressure the fewer num?ber of pass required but with decreased head rice recovery. In particular, when using high feed rates, the total number of passes should be increased to more than three by reducing the counter-pressure level to avoid decreaseases in head rice recovery (less than 65 percent head rice recovery on the basis of brown rice) at every cylinder speed. 7. A rapid rise in grain temperature seemed to have a close relationship with the pressure generated inside the whitening chamber and, subsequently with head rice reco?very rates. The higher the rate of increase, the lower were the resulting head rice recoveries.

Mechanical and Operational Factors Affecting the Efficiency of Rice Polishing Machines (정미기의 능률에 미치는 기계적 요인및 작동조건에 관한 연구)

  • 노상하;최재갑
    • Journal of Biosystems Engineering
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    • v.1 no.1
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    • pp.17-48
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    • 1976
  • In analyzing the operational characteristics of a rice whitening machine, the internal radial pressure of the machine was measured using strain gage equipment. Changes in cylinder and feed screw configurations, screen type, cylinder speed and counter-pressure levels were examined to determine their impact on the quality and quantity of milled rice and the performance of the machine. The results are summarized as follows: 1. The internal radial pressure in the whitening chamber varied with the surface condition of the grain being processed. During the first or second pass through the machine, pressure was relatively low, reached a maximum after two to three passes with combinations I and II, three to six with combination III and then began to fall. 2. The pitch of the feed screw and the size of the feed gate opening which determine the rate of entry of grain into the whitening chamber, appeared to be the most important factor aff-::cting the degree of radial pressure, quality and quantity of milled rice and the efficiency of the machine. Using a feed screw with a wide pitch (4.8cm), radial pressure was relatively high and head rice recovery ratio \vere quite low. In this case capacity and machine effic\ulcorneriency were much higher than obtained when using a feed screw with a narrow pitch (2.3cm). Very significant responses in radial pressure, head rice recovery rates and machine capacity were observed with changes in cylinder speed and counter-pressure levels when using the wide pitch feed screw. 3. The characteristics of the screen which surrounds the whitening chamber had an important effect on whitening efficiency. The existence of small protuberances on the original screen resulted in significant increases in both machine capacity and efficiency but without a significant decrease in head rice recovery or development of excessive radial pressure. Further work is required to determine the effects of screen surface conditions and the shape of the cylinderical steel roller on the rate of bran removal, machine efficiency and recovery rates. The size of the slotted perforations 0:1 the screen affects total milled rice recovery. The opening size on the original screen was fabricated to accommodate the round shape of Japonica rice varieties but was not suitable for the more slender Indica type. Milling Indica varieties with this screen resulted in a reduction in total milled rice recovery. 4. An increase in cylinder speed from 380 to 820 rpm produced a positive effect on head rice recovery for all machine combinations at every level of counter-pressure used in the tests. Head rice recovery was considerably lower at 380rpm using a wide screw pitch when compared to the results obtained at speeds from 600 to 820 r.p.m. The effects of cylinder speed On radial pressure, capacity and machine efficiency showed contrasting results, depending on the width of the feed screw pitch. With a narrow feed screw pitch (2.3cm), a direct proportional relationship was observed bet\ulcornerween cylinder speed and both radial pressure and machine efficiency. In contrast, using a 4.8 centimeter pitch feed roller produced a series of inverse relationships between the above variables. Based on the results of this study it is recommended when milling Indica type long grain rice varieties that the cylinder speed of the original machine be increased from 500-600 rmp up to a minimum of 800 rpm to obtain a greater abrasive effect between the grain and the screen. The pitch of the feed screw should be also reduced to decr\ulcornerease the level of internal radial pressure and to obtain higher machine efficiency and increased quality of milled rice with increased cylinder speeds. Further study on the interaction between cylinder speed and feed screw pitch is recommended. 5. An increase in the counter pressure level produced a negative effect On the head rice recovery with an increase in radial pressure, capacity, and machine efficiency over all combinations and at every level of cylinder speed. 6. Head rice recovery rates were conditioned primarily by the pressure inside the whitening chamber. According to the empirical cha racteristics curve developed in this study, the relationships of head rice recovery ($Y_h$) and machine capacity ($Y_c$/TEX>) to internal radial pressure ($X_p$) followed an inverse quadratic function and a linear function respectively: $$Y_h^\Delta=\frac{1}{{1.4383-0.2951X_p^\ast+0.1425X_p^{\ast\ast}}^2} , (R^2=0.98)$$ $$Y_c^\Delta=-305.83+374.37X_p^{\ast\ast}, (R^2=0.88)$$ The correlation between capacity and power consumption per unit of brown rice expressed in the following exponential function: $$Y_c^\Delta=1.63Y_c^{-0.7786^\{\ast\ast}, (R^2=0.94)$$ These relationships indicate that when radial pressure increases above a certain range (1. 6 to 2.0 kg/$cm^2$ based On the results of the experiment) head ricerecovery decrea\ulcornerses in a quadratic relation with a inear increase in capacity but without any decrease in power consump tion per unit of brown rice. On the other hand, if radial pressure is below the range shown above, power consumption increases dramatically with a lin\ulcornerear decrease in capacity but without significant increases in head rice recovery. During the operation of a given whitening machine, the optimum radial pressure range or the correct capacity range should be selected by controlling the feed rate and/or counter-pressure keeping in mind the condition of the grain, particulary the hardness. It was observed that the total number of passes is related to radial pessure level, feed rate and counter-pressure level. The higher theradial pressure the fewer num\ulcornerber of pass required but with decreased head rice recovery. In particular, when using high feed rates, the total number of passes should be increased to more than three by reducing the counter-pressure level to avoid decreaseases in head rice recovery (less than 65 percent head rice recovery on the basis of brown rice) at every cylinder speed. 7. A rapid rise in grain temperature seemed to have a close relationship with the pressure generated inside the whitening chamber and, subsequently with head rice reco\ulcornervery rates. The higher the rate of increase, the lower were the resulting head rice recoveries.

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1910's Tap-gol Park Construction Process through Design Document Interpretation (설계도서를 중심으로 본 1910년대 탑골공원의 성립과정)

  • Kim, Hai-Gyoung;Kim, Young-Soo;Yun, Hye-Jin
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.31 no.2
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    • pp.103-117
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    • 2013
  • This research analyzed the spatial components and establishment of the Tap-gol Park according to the plans between 1897 to 1916 when the discussions on the construction of the park began and it was accomplished as an urban park. The results are as follows. The establishment of Tap-gol Park can be divided by three period. Firstly, Tap-gol Park was owned by the royal family from 1987 to 1904. The discussions on construction of Tap-gol Park as a first urban park of Gyeongseong(京城) in 1897, and the private houses were tear down in order to secure land for the park in 1899. Gates and fences surrounding of Tap-gol Park were organized and it was opened in 1902 based on park plane of turtle - shaped. The octagonal pavilion for 'Lee-Wang-Jik musical band(李王職音樂隊)' was relocated in the southwestern part of the park in 1903. Secondly, Tap-gol Park was used actively by the public between 1910 to 1913, because it was opened for individuals. Also The boundary of Park were changed by surrounding facilities and recreational facilities and benefits was complemented for users. Tap-gol park was opened at nighttime in August 1913. Tap-gol Park was used as a place of amusement park. Thirdly, commercial facilities were made as the park facility between 1914 to 1916. The purpose of 'Kkikdajeom(喫茶店)' was similar to the one of modern cafes. It was built as a typical Japanese tea-house with a small pond having an island and a bridge constructed inside. With the increase of usage of Tap-gol Park as a recreational area by the citizens in 1916, the pavilion as a rest area and toilet as amenities were supplemented. Superintendent's office was equipped too. Simple chairs made from the wooden logs were installed around greenhouse, concert hall, the Wongaksa Buddhist temple(圓覺寺址十層石塔), and the flower garden was fenced round. After the relocation of Yongsan music band to Tap-gol Park, the existing concert hall was demolished. The shape of the park which was seen from the pictures of the magazines of 1920s were achieved as early as 1916. The importance of this research includes the basis to revise the errors of the preexistence researches and value of historical material of the design plan reference of the park which was accomplished during the Japanese colonial era. Also this research is to study on the spatial components of the modern landscape architecture and parks.

Brittle rock property and damage index assessment for predicting brittle failure in underground opening (지하공동의 취성파괴 예측을 위한 암석물성 및 손상지수 평가)

  • Lee, Kang-Hyun;Bang, Joon-Ho;Kim, Jin-Ha;Kim, Sang-Ho;Lee, In-Mo
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.11 no.4
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    • pp.327-351
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    • 2009
  • Laboratory tests are performed in this paper to investigate the brittle failure characteristics of over-stressed rocks taken in deep depth. Also, numerical simulation performed using that the so-called CWFS(Cohesion Weakening Frictional Strengthening) model is known to predict brittle failure phenomenon reasonably well. The most typical rock types of Korean peninsula - granite and gneiss - were used for testing. Results of uniaxial compression tests showed that the crack initiation stress was about 41 % to 42% of the uniaxial compressive strength regardless of rock types, where as, the crack damage stress of granite was about 75%, and that of gneiss was about 97%. Through the damage-controlled test, strength parameters of each rock were obtained as a function of damage degree. After the peak, the crack damage stress and the maximum stress were decreased, The cohesion was decreased and the friction angle was increased with increase of rock damage. Before reaching the peak, the elastic modulus was slightly increased, while decreased after the peak. Poisson's ratio was increased as the damage of rock proceeds. Comparison of uniaxial compression tests and damage-controlled tests shows the crack initiation stress estimated from the damage-controlled test fluctuated within the range of crack initiation stress obtained from the uniaxial compression test; the crack damage stress was less than that estimated from the uniaxial compression test. In order to predict the critical depth that brittle failure occurs, numerical simulations using the CWFS model were performed for an example site. Material parameters obtained from the laboratory tests mentioned above were used for CWFS simulation. Comparison between the critical depth predicted from the numerical simulation using the CWFS model and that predicted by using the damage index proposed by Martin et al.(l999), showed that critical depth cannot be reasonably predicted by the currently used damage index except for circular tunnels. A modified damage index was proposed by the author which takes the shape of tunnels other than circular into account.

A Study on the Design Development and Construction Process in British Airways London Eye (런던아이의 디자인 전개와 건립과정에 관한 연구)

  • Woo, Dae-Seung
    • Journal of architectural history
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    • v.15 no.1 s.45
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    • pp.7-27
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    • 2006
  • This study aims to identify and analyze the factors that influenced the construction of London Eye which was led by private groups, including characteristics in progress, differentiated value in design, the combination of technology and design, and construction costs. The results of this study were the followings. 1) London Eye provides a new construction method for a landmark in the downtown in that the architects became the clients of the project which might have been hoarded, procuring the construction costs and completing it by themselves. 2) London Eye presents a space utilization method where undeveloped spaces in the downtown are used in three-dimensions by erecting a structure on the river with a minimum land. 3) The process of design, production and erection is propelled the realization of technical intention design with one system and from at the initial stage, the participation of the engineer where the designer is equal with you must accompany. 4) London Eye is endowed with strong shape by a circle in design concept, which is the simplest geometrical figure, and it provides organic relationship between the past and the present by utilizing historical elements in various ways. 5) The construction was completed through four phases including idea phase, promotion phase, turn-key contract phase, and design-build phase. The most critical factor to the success is derived from the direct contact with Involved companies from the production phase. 6) In a project facing many challenges in terms of technology, the design-build method proves to be a more effective method than turn-key contract in that it may more allocate risks and enable coherent implementation of the core concept in design. The organization for the design-build method was composed of three phases including general affairs, responsible contracting by sector, and cooperative system by sector. Since that was a new concept structure, high-level contractors who hadn't had existing cooperative relationships with one another formed new cooperative relationship, while collaborating companies who had long cooperated led the responsible contracting and sub-cooperative system, which resulted in reduction of risks and time. 7) The major factors to change design were the design characteristics, derived from a technically great combination, and the opening time. 8) A new erection method was applied to London Eye, a structure that overcame the limitation in land and period, and the process of installation demonstrated that it is an important value for the construction of a landmark in the city. 9) In spite of many visitors and tremendous operational income, the factors that London Eye fails to free itself from debts include the construction costs expended double than expected, and interest burden to the investments, which occurred in the course of procuring the costs. Absolute limit in time increased the construction costs, resulting in being a great obstacle in the course of operation.

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