• Geomechanics and Engineering
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• v.35 no.5
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• pp.511-523
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• 2023

Canal-side roads frequently collapse due to an unexpectedly greater soft-clay thickness with a rapid drawdown situation. This causes annually increased repair and reconstruction costs. This paper aims to explore the effect of soft-clay thickness on the failure in the canal-side road in the case study of Phra Nakhon Si Ayutthaya rural road no. 1043 (AY. 1043). Before the actual construction, a field vane shear test was performed to determine the undrained shear strength and identify the thickness of the soft clay at the AY. 1043 area. After establishing the usability of AY. 1043, the resistivity survey method was used to evaluate the thickness of the soft clay layer at the failure zone. The screw driving sounding test was used to evaluate the undrained shear strength for the road structure with a medium-stiff clay layer at the failure zone for applying to the numerical model. This model was simulated to confirm the effect of soft-clay thickness on the failure of the canal-side road. The monitoring and testing results showed the tendency of rapid drawdown failure when the canal-side road was located on > 9 m thick of soft clay with a sensitivity > 4.5. The result indicates that the combination of resistivity survey and field vane shear test can be successfully used to inspect the soft-clay thickness and sensitivity before construction. The preliminary design for preventing failure or improving the stability of the canal-side road should be considered before construction under the critical thickness and sensitivity values of the soft clay.

• International Journal of Concrete Structures and Materials
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• v.18 no.1E
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• pp.55-61
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• 2006

RC shear walls are frequently used as lateral force-resisting system in building construction because they have sufficient stiffness and strength against damage and collapse. If RC shear walls are properly designed and proportioned, these walls can also behave as ductile flexural members like cantilevered beams. To achieve this goal, the designer should provide adequate strength and deformation capacity of shear walls corresponding to the anticipated deformation level. In this study, the level of demands for deformation of shear walls was investigated using a displacement-based design approach. Also, deformation capacities of shear walls are evaluated through laboratory tests of shear walls with specific transverse confinement widely used in Korea. Four full-scale wall specimens with different wall boundary details and cross-sections were constructed for the experiment. The displacement-based design approach could be used to determine the deformation demands and capacities depending on the aspect ratio, ratio of wall area to floor plan area, flexural reinforcement ratio, and axial load ratio. Also, the specific boundary detailing for shear wall can be applied to enhance the deformation capacity of the shear wall.

• The Korean Journal of Emergency Medical Services
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• v.10 no.1
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• pp.23-39
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• 2006

In Korea, There are many disasters, like the collapse of Sampung department store, the strike of severe typhoon 'Rusa' and the subway tragedy in Taegu, because of global warming, urbanization, high-density and high-rise of buildings. So, the government made 'The Framework Act' on the safe and management of disaster and 'The National Emergency Management Agency' was established. But emergency medical service systems in Korea is not growing so much. The purpose of this research is to give basic data for the development of emergency medical service systems in Disaster by comparing of disaster management systems and emergency medical systems among the nations of the world, analysing emergency medical systems in disaster in Korea and suggesting some improvement methods. The improvment methods are like this ; First, establishing the National Disaster Medical System in Korea, making the good triage by EMT, expansion of EMT's working area, developing protocols and framing of medical director increasing the working force of EMT, broad inner cavity of ambulance for treatment of patientent, supplement of professional equipments, active using of helicopters are needed in prehospital are. Second, equal establishment of emergency medical center and increase of working force of emergency medical team are needed in hospital area. Finally, enforcement of the dispatcher's qualification, smooth communication among EMSS systems and actualization of medical direction through screen are needed in the Telecommunication system.

• Korean Institute of Interior Design Journal
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• v.27 no.3
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• pp.49-61
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• 2018

Korea achieved compressed growth through rapid industrialization. However, the housing policy of this period was driven by the provision of large scale public rental housing and redevelopment of residential areas, resulting in community collapse and social exclusion. Meanwhile, Korean society needs new housing types and management methods as housing demand varies due to low birthrate, aging, and growing numbers of single-person households. Therefore, in order to realize social integration community that solves these problems by themselves, it is necessary to plan housing that can enhance community in residential space. In this reason, the purpose of this study is to derive the characteristics of social integration plan of community housing which is supplied mainly in the metropolitan area. Accordingly, the subjects of this study were housing cases designed to enhance social integration by promoting community activation in Seoul and Gyeonggi-do. The results of this study are as follows: First, it is necessary to flexibly apply the type and range of community housing. Second, It is needed to have a housing plan considering various characteristics of resident community. Third, social integrated community housing requires not only physical planning, but also mechanism to operate it.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.8 no.2
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• pp.362-366
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• 2007

As the industry of 21C has been developed, the gas industry has been grown and its convenience but it accompany risk for using gas. Therefore, we designed a vent area to prevent the collapse of the booth by the explosion pressure during test. The explosion booth was installed fur training safety supervisors to aware the risk of gas explosion. The vent area was designed based on the exhaust model of NFPA 68. It was calculated at $2.8297m^2$ for LPG and at $3.0518m^2$ for NG.

• Archives of Plastic Surgery
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• v.48 no.2
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• pp.158-164
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• 2021

Background In lower lateral cartilage (LLC) surgery, cephalic trimming poses risks for the collapse of the internal and external nasal valves, pinched nose, and drooping deformity. The cephalic lateral crural advancement (CLCA) technique presented herein was aimed at using a flap to increase nasal tip rotation and support the lateral crus, in addition to the internal and external nasal valves, by avoiding grafts without performing excision. Methods This study included 32 patients (18 female and 14 male) and the follow-up period for patients having undergone primer open rhinoplasty was 12 months. The LLC was elevated from the vestibular skin using the CLCA flap. A cephalic incision was performed without cephalic trimming. Two independent flaps were formed while preserving the scroll ligament complex. The CLCA flap was advanced onto the lower lateral crus while leaving the scroll area intact. The obtained data were analyzed retrospectively. Results The mean age of the patients was 31.6 years (range, 20-51 years). The Rhinoplasty Outcome Examination scores after 12 months varied from 90 to100 points, and 93% of patients reported perfect satisfaction. At a 1-year follow-up, the patients' nasal patency (visual analogue scale) rose from 4.56±1.53 (out of 10) to 9.0±0.65 (P<0.001). Conclusions The CLCA flap led to better nasal tip definition by protecting the scroll area, increasing tip rotation, and supporting the internal and external nasal valves without cephalic excision.

• Geomechanics and Engineering
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• v.32 no.2
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• pp.209-232
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• 2023

A comprehensive study was conducted to design economical foundations for a number of buildings on soft cohesive soil in the southern coastal regions of Iran. Both static and seismic loads were considered in the design process. Cyclic experiments indicated that the cohesive soil of the area has potential for softening. Consequently, the major challenge in the design stages was relatively high dimensions of settlement, under both static and seismic loadings. Routine soil-improvement methods were too costly for the vast area of the project. After detailed numerical modeling of different scenarios, we concluded that, in following a performance-based design approach and applying a special time schedule of construction, most of the settlement would dissipate during the construction of the buildings. Making the foundation as rigid as possible was another way to prevent any probable differential settlement. Stiff subgrade of stone and lime mortar under the grid foundation and a reinforced concrete slab on the foundation were considered as appropriate to this effect. In favor of an economical design, in case the design earthquake strikes the site, the estimations indicate no collapse of the buildings even if considerable uniform settlements may occur. This is a considerable alternative design to costly soil-improvement methods.

• Korean Journal of Heritage: History & Science
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• v.42 no.3
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• pp.66-87
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• 2009

The definition of the structure of wooden chamber tomb(piled stone-type) is as follows. It is a tomb with wooden chamber, and stones were piled on top of the wooden chamber, and then a wooden structure was placed on top of the piled stones, and more stones were piled on top of the wooden structure, and sealed with clay. Of course this definition can vary according to periods, the buried, etc. Gyeongju-style piled stone type wooden chamber tombs have some distinguished characteristics compared to general definition of piled stone type wooden chamber tombs. Outside the wooden chamber, either stone embankments or filled-in stones were layed out, and pilet-in stones are positioned right above the wooden chamber, and almost every class used this type, and finally, it is exclusively found in Gyeongju area. First generations of this Gyeongju-style piled stone type wooden chamber tombs appeared in first half of 5th century. These tombs inherited characteristics like ground plan, wooden chamber, double chamber(inner chamber and outer chamber), piled stones, burial of the living with the dead, piled stones, from precedent wooden chamber tombs. However these tombs have explicit new characteristics which are not found in the precedent wooden chamber tombs such as stone embankments, wooden pillars, piled stones(above ground level), soil tumuluses. stone embankments and wooden pillars are exclusively found on great piled stone type above-ground level wooden chamber tombs such as the Hwangnamdaechong(皇南大塚). Stone embankments, wooden pillars, piled stones(above ground level) are all elements of building process of soil tumuluses. stone embankments support outer wall of above-ground level wooden chambers and disperse the weight of tumuluses. Wooden pillars functioned as auxiliary supports with wooden structures to prevent the collapse of stone embankments. Piled stones are consists of stones of regular size, placed on the wooden structure. And after the piled stones were sealed with clay, tumulus was built with soil. Piled stones are unique characteristics which reflects the environment of Gyeongju area. Piled stone type wooden chamber tombs are located on the vast and plain river basin of Hyeongsan river(兄山江). Which makes vast source of sands and pebbles. Therefore, tumulus of these tombs contains large amount of sands and are prone to collapse if soil tumulus was built directly on the wooden structure. Consequently, to maintain external shape of the tumulus and to prevent collapse of inner structure, piled stones and clay-sealing was made. In this way, they can prevent total collapse of the tombs even if the tumulus was washed away. The soil tumulus is a characteristic which emerges when a nation or political entity reaches certain growing stage. It can be said that after birth of a nation, growing stage follows and social structure will change, and a newly emerged ruling class starts building new tombs, instead of precedent wooden chamber tombs. In this process, soil tumulus was built and the size and structure of the tombs differ according to the ruling class. Ground plan, stone embankments, number of the persons buried alive with the dead, quantity and quality of artifacts reflect social status of the ruling class. In conclusion, Gyeongju-style piled stone type wooden chamber tombs emerged with different characteristics from the precedent wooden chamber tombs when Shilla reached growing stage.

• Journal of the Korean Geographical Society
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• v.43 no.4
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• pp.466-476
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• 2008

Gurin Cave, 442 m long, is a lava tube developed on the northern slope of Mount Halla. Seventy-three meters of its lower reach became a river channel since Byeongmun River flowed into a window after roof collapse took place. The subterranean channel has a width of 447 cm and a height of 501 cm, respectively. Its banks show well-developed lava shelves of a typical lava tube, while its floor has sculpted forms which characterize a bed of a bedrock stream. The reach is likely to be collapsed and then has four collapsed windows since its roof has the densely developed testudinal joints and consists of thin lavas with a thickness of 30 to 60 cm. Before the subterranean channel appeared, a ground channel flowed over the cave and joined into a main channel of Byeongmun River at 653 m in altitude. However, the subterranean channel substituted the ground channel since a bed of the ground channel collapsed into the cave. The new channel, flowing through the cave, joined into a main channel at 660 m in altitude. As the drainage area of Byeongmun River expanded upstream the cave, the new channel changed into a main channel. Since floodwater flows down the ground channel as well as the subterranean channel, a distributary stream has temporarily appeared at the collapsed window. Lava tubes are likely to have an affect on the development of river system in Jeiu Island, in that the caves have constantly shown roof-fall.

• Journal of the Korean Geosynthetics Society
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• v.15 no.2
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• pp.55-64
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• 2016

The construction of the road NATM tunnel, which undergoes the weathered zone of the mountain, was in process with the reinforcement methods such as the rock bolt, shotcrete depositing, and the multi step grout with large diameter steel pipe. The collapse from the ceiling, and on the ground surface area(sink hole), of which were measured to be 25m from the ground surface($V=12m(W){\times}14m(L){\times}5m(H)=840m^3$), as well as excessive displacements in the tunnel, had occurred. In order to execute the necessary reconstruction work, the causes of the surface collapses were inspected through the field investigation, in-situ tests, and numerical analysis. As a result, several proper solutions were suggested for both internal and external reinforcements for the tunnel. As a result of numerical analysis, the collapsed zone of the tunnel was reinforced up to 0.5D~1.0D laterally by the cement grouting on the ground surface, 0.5D longitudinally by the multi step grout with large diameter steel pipe in tunnel. With further reinforcement implemented by rebars in lining, the forward horizontal boring was executed to the rest of the tunnel to evaluate the overall status of the tunnel face. Appropriate reinforcement methods were provided if needed.