• Geomechanics and Engineering
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• v.29 no.4
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• pp.471-486
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• 2022

The effect of segmental joints is one of main importance for the segmental lining design when tunnels are excavated by a mechanized process. In this paper, segmental tunnel linings are analyzed by two numerical methods, namely the Beam-Spring Method (BSM) and the Solid-Interface Method (SIM). For this purpose, the Tehran Subway Line 6 Tunnel is considered to be the reference case. Comprehensive 2D numerical simulations are performed considering the soil's calibrated plastic hardening model (PH). Also, an advanced 3D numerical model was used to obtain the stress relaxation value. The SIM numerical model is conducted to calculate the average rotational stiffness of the longitudinal joints considering the joints bending moment distribution and joints openings. Then, based on the BSM, a sensitivity analysis was performed to investigate the influence of the ground rigidity, depth to diameter ratios, slippage between the segment and ground, segment thickness, number of segments and pattern of joints. The findings indicate that when the longitudinal joints are flexible, the soil-segment interaction effect is significant. The joint rotational stiffness effect becomes remarkable with increasing the segment thickness, segment number, and tunnel depth. The pattern of longitudinal joints, in addition to the joint stiffness ratio and number of segments, also depends on the placement of longitudinal joints of the key segment in the tunnel crown (similar to patterns B and B').

• Journal of The Korean Society of Grassland and Forage Science
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• v.6 no.3
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• pp.138-144
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• 1986

This trial was carried out to find out the methods of improvement of natural pasture by PK-fertilization and sheep grazing. The experimental area covered with the community of Carex ferruginea-dominated and located at the Bavarian Alps in the southern part of Germany. As measuring the changes of the vegetation, the Releve-method, the Point-Intercept-method and the Quadrat-Charting-method were applied. Changes in the ecological evidence of the vegetation were studied during the period from April 1980 to the end of growing season in 1983. 1. The fodder value at the oversown pasture we slightly increased by PK-fertilization with sheep grazing, byt that gradually decreased by grazing without fertilization. 2. The pasture quality at the secondary vegetation was greatly improved as well as that of the oversown pasture in Autumn of the second experimental year by sheep grazing with PK-fertilization, but the fodder value was not like that by grazing without fertilization at the natural pasture. 3. The influence of phosphorus/ potassium-fertilization was much more serious than that of sheep grazing. Sedges almost disappeared due to fertilization, on the other hand grasses and legumes increased distinctly. Sheep grazing without fertilization led to a gradual decrease of legumes. The enormous biomass difference in sedges between the June and October analyses was due to a lack of regenerative capacity. 4. The plant community of Carex ferruginea-dominated before the experiment was successived into Alchemillo-Cynosuretum by PK-fertilization with sheep grazing.

• The Korean Journal of Ecology
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• v.26 no.5
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• pp.281-287
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• 2003

We present the first analysis of moor vegetation on the Moojechi of Ulsan including syntaxonomy and syndynamics. We classified plant communities according to the Braun-Blanquet approach. In order to better understand ecological alteration processes and changing species compositions along successional gradients we also examined synecological differences using Principal Coordinate Analysis(PCoA) in terms of moisture gradient, species richness, and community structure. Classification resulted in one association and five plant communities occupying distinct moor habitats: Hypericum laxum-Eleocharis acicularis for. longiseta community, Drosera rotundifolia-Eleocharis congesta community, Platanthero-Molinietum japonicae ass. nova hoc loco, Molinia japonica-Alnus japonica community, Miscanthus sinensis-Pinus densiflora community, and Convallaria keiskei-Quercus serrata community. Due to synecological correspondences and floristic similarities in supraregional perspective, Platanthero-Molinietum can be assigned to existing higher syntaxonomic units of Molinion and Molinietalia in Braun-Blanquet system, established in Japan. We propose to extend their range and designate the new class Molinietea japonicae representative to the intermediate moor (Zwischenmoor) vegetation in Northeast Asia. PCoA resulted in four types showing a sequencess of succession: Needle spike-rush type, moor-grass type (incl. alder forest type), eulalia type, and oak forest type. A combination of edaphic conditions (soil eutrphication and soil moisture) and hydrologic patterns of moor ecosystem related to topography, occurring as result of external geophysical forces, controls inter alia spatial patterns and floristic compositions of moor plant communities.

• Journal of the Society of Naval Architects of Korea
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• v.51 no.4
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• pp.283-290
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• 2014

Environmental changes, especially global climate change, are creating new routes to reduce a shipping service distance in Arctic area. The Arctic routes are shorter than 60% of existing ways Panama or Suez canal). For this reason, ship owners prefer to navigate in Arctic area and a transportation of goods though the Arctic area is increasing. But the low temperature in Arctic condition changes the material properties. Especially, the material will be brittle and strength will increase. And an ultimate strength analysis of ship stiffened panels is changed depending on temperatures. In present study, the ultimate strength analysis of stiffened panels in double hull oil tankers is performed under various low temperatures with the material properties obtained by tensile coupon test. The analytical method as named ALPS/ULSAP was used for analysis method and 6 kinds of temperature (20, 0, -20, -40, -60 and $-80^{\circ}C$) were considered to investigate the effect of Arctic conditions.

• Journal of architectural history
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• v.11 no.2 s.30
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• pp.7-22
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• 2002

Architectural style is said to be product reflecting political, social and cultural condition. Especially, in colony, architectural style is strongly related to political condition or policy. After colonization in 1910, public buildings with western historical architectural style in Japanese version were widely built by Japanese colonial government in Korea. And in the late 1920s, modernism style in architecture became dominant in Korea as like other countries. In this situation, curious buildings in strange architectural styles came out. One example is railroad station buildings with traditional Korean architectural style and timber house station having a steep roof which is widely used in North Europe such as Alps area with good sights and mountains. Generally, the colonizer says that colonization is the only way to save the colony at crisis defined by colonizer and they insist that they can help the colony modernize. To justify colonization, the colonizer attributes the colonization to the characteristics of the nation and stagnation of the traditional culture etc.. Accordingly, the colonizer tries to depreciate colony's traditional value and culture. In case of colony which has similar cultural background historically (in this case, economical exploitation is less important than other Asian colony by European power), this depreciation of traditional value and culture in Korea was done more strongly than others. At this time, we should understand special relation between Korea and Japan historically. Even though, colony's locality is adopted by the colonizer in public fields, which is based on political purpose or exotic taste etc.. In early days of Japanese ruling period, Japan never use the Korean traditional facts in public. Therefore there is no use of Korean traditional architectural style in public field. In late 1920s, some railroad station buildings were constructed in new styles without precedence in modern Korea. One is railroad station buildings in Korean traditional architectural style, the other is railroad station buildings in timber house stations having a steep roof which is different form western historical architectural style. It was mystery that Japan had constructed railroad stations in Korean traditional style which Japan had tried to destroy together with Western style railroad station buildings. This paper is made to solve the mystery why the colonizer(Japan) constructed entirely different types of railroad stations at the same time in the late 1920s and 1930s. The key point to solve this mystery is tourism. In this paper, to solve this mystery, I try to use terminology' 'Colonial Tourism' in architecture why colonial power had constructed railroad stations with colony's traditional architectural style and Western style having a steep roof which can be seen north European region.

• Journal of The Geomorphological Association of Korea
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• v.17 no.2
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• pp.1-13
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• 2010

The technique of mountain ordering developed by Yamada(1999) has been tested to two small islands (Namhaedo: 301km², Geojedo: 378km²). The results and experiences above were extended and applied to the whole area of the southern part of Korean Peninsula. Three areas such as Seorak-Taebaek Mountains, Jiri-Deogyu Mountains, and Youngnam Alps are identified as the highest, 5th order mountains. 10 areas are classified as the 4th order and 87 areas as the 3rd order. It is suggested that the 5th order mountains are related to the axis of uplift and the 4th and 3rd order mountains have the same direction (NE-SW) as that of the secondary mountain systems in the Korean Peninsula. The logarithmic values of number, area, and relative altitude of the ordered mountains have the linear relationship with the order, as the laws of stream order. The several mountains which are not included in the existing mountain systems could be identified among the ordered mountains, and those mountains could be used as the basis to understand the geological structure of the Korean Peninsula. Most of the National Parks and the Provincial Parks are distributed on the 3rd, 4th, 5th order mountains. It is especially confirmed that the Songnisan National Park take a role to link the Seorak-Taebaek Mountains and Jiri-Deogyu Mountains as a important ecological axis. Therefore, it would be validated that the technique of mountain ordering has the practical values as well as the geomorphological significances.

• The Korean Journal of Air & Space Law and Policy
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• v.30 no.2
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• pp.279-310
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• 2015

The Montreal Convention is an agreement that governs the liability of air carriers for injury and death to passengers travelling internationally by air. The Montreal Convention serves as the exclusive legal framework for victims and survivors seeking compensation for injuries or death arising from accidents involving international air travel. The Montreal Convention sets monetary liability caps on damages in order to promote the financial stability of the international airline transport industry and protect the industry from exorbitant damages awards in courts that would inevitably bankrupt an airline. The Convention allows a litigant suing under the Convention to avoid the liability caps in instances where the airline's culpability for the injury or death is the direct result of negligence, another wrongful act, or an omission of the airline or its agents. The Montreal Convention identifies specific locations as appropriate venues to advance claims for litigants seeking compensation. These venues are closely tied to either the carrier's business operations or the passenger's domicile. In March 2015, in an act of suicide stemming from reactive depression, the co-pilot of Germanwings flight 9525 intentionally crashed the aircraft into the French Alps killing the passengers and the remaining crew. Subsequent to the crash, there were media reports that Lufthansa made varying settlement offers to families of the passengers who died aboard the flight ranging from $8,300 USD to $4.5 Million USD depending on the passengers' citizenship. The unverified offers by Lufthansa prompted outcries from the families of the decedent passengers that they would institute suit against the airline in a more plaintiff friendly jurisdiction such as the United States. The first part of this article accomplishes two goals. First, it examines the Montreal Convention's venue requirement along with an overview of the recoverable damages from countries comprising the citizenship of the passengers who were not American. The intentional crash of Germanwings flight 9525 by its First Officer encompasses the possibility that Lufthansa may be exposed to unlimited compensatory damages beyond the liability caps contained in the Convention. The second part of this article explores the application of the Convention's liability limits to the Germanwings flight to demonstrate that the likelihood of escaping the liability limits is slim.