• Proceedings of the Korean Geotechical Society Conference
• /
• 1999.10a
• /
• pp.449-456
• /
• 1999

The concrete wall is the most useful of retaining structure which can obtain the engineering stability, but has problems that is not friendly with nature environment in a fine view, such as poor rear drainage, and shrinkage crack by temperature difference, etc. Because of this problems, the research for a segmental crib retaining wall has been performed. A segmental crib retaining wall is quickly and easily erected because is possible to be erected as the individual members, and is not sensitive to differential settlement and earthquakes. Also, it shows effective drainage and has a friendly advantage with nature environment because of being able to be planted with vines and shrubs in retaining walls The design of crib retaining walls has traditionally been based on classical soil mechanics theories. These theories, originally derived by Rankine(1857) and Coulomb(1776), assume that the wall acts as a rigid body. This assumption results in failure being predicted by either monolithic overturning or base sliding mechanisms. However, the wall consists of individual members which have been created a three dimensional grid. This grid confines an fill mass which becomes part of the wall. The filled wall resists the earth pressure with the same mechanism of classical gravity walls. Because of the flexibility of the individual segment, it allows relative movement between the individual members within the wall. The three dimensional flexible grid leads to stress redistribution when the wall is subjected to external or fill loads. Due to the flexibility and the stress redistribution, the failure of segmental crib wall consists of not only overturing and base sliding but the local deformation and the failure between the segmental members. It has been researched in the field that due to this flexibility and load redistribution, serviceability failure of segmental crib walls is unlikely to be due to overturning or base sliding. Therefore, in this study, the relative displacement appearance of retaining wall due to variation of inclination is measured to examine this behavior characteristics. Also, the behavior characteristics of retaining walls by surcharge load, and location of acting point of retaining wall rear, and the displacement characteristics and deflections are estimated about the existence and nonexistence of Rear Stretcher performing an role in transmitting earth pressure of Header and Stretcher organizing retaining walls. This research focuses on the characteristics due to the behavior of retaining walls. This research focuses on the characteristics due to the behavior of retaining walls.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.20 no.11
• /
• pp.130-135
• /
• 2019

This study performed the quality improvement of a red dot sight for a 40 mm grenade launcher through parallax reduction. The red dot sight cited in this study is currently in mass production for military use as a non-weapon system. While the red dot sight's parallax currently meets requirements, slightly greater error was observed on the outside of effective optical area of the reflection lens compared to other sights. Parallax is easily affected by eye movement, which can result in aiming error. To improve the red dot sight's quality, this study analyzed why parallax is observed in the effective optical area of the reflection lens and how to reduce it. As a result, the red dot sight demonstrated lower parallax error using the new optical system design with an increased reflection lens thickness and modified components configuration related to the reflection lens assembly. Parallax was calculated and simulated by using a particular program to verify that it decreased. This improvement for the 40 mm. grenade launcher red dot sight more than satisfies requirements, offers advanced capabilities for users, and as a result, successful operation carryout.

• Journal of the Korean association of regional geographers
• /
• v.17 no.6
• /
• pp.649-665
• /
• 2011

Estuary of River Nakdong(in south-eastern coast of Korean Peninsula) is the most representative site of delta in Korea. This study is to elucidate morpho-structural background associated with the embayment area and sedimentation processes, having allowed development of the delta. In this area, Great morphological trait of the embayment area had been formulated by differential erosion exploiting regional fracture system(NNE-SSW, NNW-SSE, E-W,...) of tectonic origin. For this reason, outline of the embayment basin shows quadrangular plan, and ridges and dissected valleys of neighbouring mountains draw frequently morphological lineament pattern. At the last glacial age when delta deposit had not yet filled the actual embayment basin of the Nakdong, mechanical weathering(frost shattering) and mass-movement processes had provided detritus materials composed of blocks, boulders on bottom the basin. With the postglacial transgression in the Holocene, the basin had been submerged, then began to be filled with fluvio-marine deposits from Kimhae-Yangsan area toward actual estuarine zone, so that Nakdong delta have been formed. Analysis and synthesis of from hundreds of boring data of the delta area reveal that progression of delta formation have been accompanied with the development of barrier islands. If the barrier islands had grown as forming a plural row, then their intervals have posteriorly filled with another fluvio-marine deposits. Besides, it shows that delta deposits are essentially alluvial. However, at the periphery of the delta, intervention of fine marine deposits is frequently found.

• Current Research on Agriculture and Life Sciences
• /
• v.9
• /
• pp.71-86
• /
• 1991

This study has tried to illuminate a shocking phenomenon, the import liberalization of agricultural products in the aspect of Consumer consciousness. It has been applied that Table Analysis by using computer programming for instance-MINITAB, and Correlation Analysis and Multiple Regression Analysis, things like that. The results of this study are as follows; 1. Comparing domestic and imported stuffs, Comsumers came to awareness that domestic products superior to foreign's in the cases of the degree of freshness, taste and pollution damage, in the meanwhile, inferior to the cases of price and wrapping. Food self-supplyment is considered as one of the most important things of all, moreover, by most comsumers and health food and conventional food are favored by high class people. 2. Bying imported stuffs could clearly be fatal blow to our agriculture is fully recognized among consumers, what is more, there would only be doomed to our agriculture, too. 3. The most mass-purchasing imported stuffs by consumers illustrates in order; Beef, Banana, Coffee and Tabacco etc. The most significant elements why consumers buy foreign product is that the prices of them are relatively lower than those of ours. Besides, the next causes lies to non-producing stuffs and curiosity. 4. It must've been generally conceived by most consumers that Open-the-market-policy has been progressed for USA's repression and our monopolistic capital. Therefore, they demand that our market should be contained against unadviciable wave, moreover, keep paying attention to the policy how it will work to protect Korean agriculture. 5. Consumer attitude toward buying imported agricultural products is double-faced, Never-buy occupied only 24.4 % among respondents, but overwhelming respondents say non-producing stuffs can be obtained selectively. In this case, however, never-buy-movement would be backed by consumers in proportion to their educational background. 6. Various consumer minds surrounding Open-the-market-situation, in the end, has been analized econometrics through eleven variables to approach accurate fulfillments.

• Cartoon and Animation Studies
• /
• s.42
• /
• pp.315-335
• /
• 2016

Culture is being created and consumed as several form by human development. Populace is forming through movement of mass of people to specific place which influenced by urbanization and industrialization. Since cultural products are created on base of economic principles cultural content makers are make culture products after lot of study and analyze. In early days popular culture was accepted only by the meaning of the text which has settled already via country or company which was holding the capital. But today we can apply culture products freely by the power of public opinion and media art's growth. Especially fandom is giving the opportunity to consume the image of cultural products actively and offering the good influence to make it by several ways of activities to the culture producers. In this study, consumption as a cultural group formed by the fandom in public will be transformed into participatory groups by the influence of cultural activities with fan art reproduction. These changes in the consumption of culture products will make it in positive way. Thereby culture creator who thinks fandom as a group of culture capital maker only use it now for the indicator for predicting success of culture products. Will find out in this study how culture consumption is accomplishing by fan fiction and fan illustration in the fandom culture and how reproduced fan art is affects to culture creators.

• Korean Journal of Agricultural Science
• /
• v.6 no.2
• /
• pp.125-133
• /
• 1979

The characteristics of landslides occurred in August 5, 1979 in pyeongchangkun were surveyed and indentified as follows. 1. Deep limestone regions. Distinct differences in soil texture between A1 and B horizon could be observed on soil profile, which is attributed to the clay illuviation. The clay illuvial horizon is supposed to be an important cause of large scale mudflows on middle slopes by the lubricant action of ground water flowing between top soil and subsoil. 2. Shallow limestone regions. Very shallow top soils (less than 50cm) laid on tilted bedrock stratification provide a proper condition of mass soil movement if the top soil is saturated and ground water flows between top soil and bedrock when concentrated heavy rainfalls shower. 3. Granite regions. Weathering granitic bedrock produces very coarse textured top soils which are very cohesionless and have many pores. Therefore, the soil has high infiltration ratio and is easy to be saturated by water and to be detached from the bedrock. The landslides abrase very severely both sides of gully with high potential energy when they flow down. The following methods for landslide prevention can be recommended. 1. The original parts of landslides on top of the gully must be treated by intensive planting of deep rooting species and check dams. 2. Clear-cutting and crop planting on steep slope (more than 25 degrees) should be controlled and prohibited. 3. Establishment of landslide prevention forest should be practised on proper site.

• Journal of the Korea Concrete Institute
• /
• v.22 no.6
• /
• pp.867-873
• /
• 2010

This study investigated the corrosion properties of reinforced concrete with the addition of steel fibers. The transport properties of steel fiber-reinforced concrete such as permeable void, absorption by capillary action, water permeability and chloride diffusion were first measured to evaluate the relationship with the corrosion of steel rebar. Test results showed a slight increase on the compressive strength with the addition of steel fibers as well as considerable improvement of penetration resistance to mass transport of harmful materials into concrete. The addition of steel fibers in reinforced concrete accelerated the initiation of steel corrosion contrary to the expected results based on the measured transport properties. The NaCl ponding surface showed the spalling failure due to the corrosion expansion of steel fibers and the cut-surface around the steel rebar showed the localized steel fiber's corrosion. The wet-dry cycling with high chloride ions as well as high temperature seems to induce the increase of salt crystallization on the pores continually and the increased pressure with the steel fiber's corrosion on the pores caused the spalling failure on the exposed surface. The microcracking on the surface therefore accelerated the movement of water, chloride ions and oxygen into the embedded steel rebar. The mechanism affecting corrosion of embedded steel reinforcement with steel fibers in this study are not yet fully understood and require further study comprising of accurate experimental design to isolate the effect of steel fiber's potential mechanism on the corrosion process.

• 한국HCI학회:학술대회논문집
• /
• 2008.02b
• /
• pp.109-114
• /
• 2008

We have long kept our Cartesian tradition in which Mind privileges over Body; the invention of printing technology has accelerated the tradition in which the intelligence and legibility of media were considered as a higher human value. However, the development of media and technology are supporting the multisensory mechanisms of the body as it was in preliterate era when we communicated with our whole bodily experiences. The development and spread of mass-media and new technologies have broaden the boundary of human sensory that are largely dominated by visual information and expanded it to auditory, olfactory and even gustatory sensation. Since 1960's, some philosophers and artists have recognized the human body as a subjective matter, starting the movement in which the body plays a role as an essential factor in study of human perception and cognition, aesthetics in art, and sociology, and the changed perspectives are practiced vigorously in the field of new media art; the theory of Maurice Merleau-Ponty who clarified the body as a general means for the body's possession of world, so that recognize the importance of cognition of one's body and approved the embodiment could be applied and practiced here. Therefore, we discuss how Merleau-Ponty's philosophical theory can be practiced and how McLuhan's perspective could be applied on the notion of body's extension in media by analysing some new media art cases.

• Progress in Medical Physics
• /
• v.20 no.3
• /
• pp.180-190
• /
• 2009

Depth of prostate volume from the skin can vary due to intra-fractional and inter-fractional movements, which may result in dose reduction to the target volume. Therefore we evaluated the feasibility of automated depth determination-based adaptive proton therapy to minimize the effect of inter-fractional movements of the prostate. Based on the center of mass method, using three fiducial gold markers in the prostate target volume, we determined the differences between the planning and treatment stages in prostate target location. Thirty-eight images from 10 patients were used to assess the automated depth determination method, which was also compared with manually determined depth values. The mean differences in prostate target location for the left to right (LR) and superior to inferior (SI) directions were 0.9 mm and 2.3 mm, respectively, while the maximum discrepancies in location in individual patients were 3.3 mm and 7.2 mm, respectively. In the bilateral beam configuration, the difference in the LR direction represents the target depth changes from 0.7 mm to 3.3 mm in this study. We found that 42.1%, 26.3% and 2.6% of thirty-eight inspections showed greater than 1 mm, 2 mm and 3 mm depth differences, respectively, between the planning and treatment stages. Adaptive planning based on automated depth determination may be a solution for inter-fractional movements of the prostate in proton therapy since small depth changes of the target can significantly reduce target dose during proton treatment of prostate cancer patients.

• The Journal of Engineering Geology
• /
• v.17 no.2 s.52
• /
• pp.163-176
• /
• 2007

Landslides which is one of the major natural hazard is defined as a mass movement of weathered material rock and debris due to gravity and can be triggered by complex mechanism. It causes enormous property damages and losses of human lift directly and indirectly. In order to mitigate landslide risk effectively, a new method is required to develope for better understanding of landslide risk based on the damaged cost produce, investment priority data, etc. In this study, we suggest a new evaluation method for slope stability using risk analysis. 30 slopes including 10 stable slopes, 10 slopes of possible failure and 10 failed slopes along the national and local roads are examined. Risk analysis comprises the hazard analysis and the consequence analysis. Risk scores evaluated by risk analysis show very clear boundaries for each category and are the highest for the failed slopes and the lowest for the stable slopes. The evaluation method for slope stability suggested by this research may define the condition and stability of slope more clearly than other methods suggested by others.