• Journal of architectural history
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• v.19 no.3
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• pp.51-70
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• 2010

This paper aims to examine the constructional background and process of the Japanese military installations of Oiyang-po(外洋浦), especially based on the military secret documents. Furthermore, it aims to analyze the characteristics of the remains. The results are as follow; 1) The number of the Japanese military secret documents concerning with the installations of Oiyang-po, summed up to 33s. Especially, 14 documents about the expropriation of the lands and houses, and the constructions of the artillery position are reserved in "Mildae-ilgi"(密大日記)written from 1893 to 1942. 2) Imperialist Japan constructed firstly the military installations of Oiyang-po against the Russo-Japanese War. After the moving of the artillery headquarters into Masan in 1911, these installations had been maintained for the defense of Busan and Jinhae Bays. 3) As soon as 1904, the lands and houses of Oiyang-po were forcibly expropriated according to (韓日議定書). The Korean Government payed the expropriation prices to the dwellers. But the amount of money were too small and were lately payed. Moreover the dwellers' fishery right were never recompensed. 4) In 1904, the artillery headquarters and position were constructed by the 3rd Chookseong-dan(築城團) under the command of Matsui, a military engineer officer. The executional constructions were accomplished by the Japanese construction contractors. 5) After the moving of the artillery headquarters into Masan in 1911, the 3rd Chookseong-dan had usually repaired and consolidated the explosive warehouses and artillery facilities. 6) The artillery position constructed with the thick concrete walls was located at the foot of the mountain in back. It's plan was similar to the rectangular shape. It reserved six 280㎜ howizers and several explosive warehouses. 7) The reserve funds and arsenal funds were used for the constructions. And the items of expenses such as the establishments of the electric lights and communication networks, and the repairs of the explosive warehouses were mainly recoded in "Mildae-ilgi".

• Journal of the Korean Institute of Gas
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• v.18 no.2
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• pp.73-80
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• 2014

The objective of this paper is to assess the service life and retrain methods of specimens, which were subjected to carbonation attack, obtained from mix proportion of Sam-cheok LNG storage tank under construction. As the results, accelerated-carbonation penetration depths of 7, 28, 56 ages indicated 4.45, 9.19, 13.37mm, and even considering for cover depths of steel of LNG storage tank under real operation, it was enough. In addition, with carbonation velocity coefficient calculated by carbonation penetration depths, the service life to design cover depth(70, 80, 90, 100mm) of PC outer tank of LNG storage tank was 779, 1017, 1287, 1589 years and 466, 609, 771, 951 years, respectively, considering the $CO_2$ concentration in air which account for the 0.03% and 0.05%. Also, the restrain methods to carbonation attack were feasible through controlling the factors affecting the changes of hydration products such as $Ca(OH)_2$, ion composition in pore solution and matter mobility of organization structures within hardened concrete.

• Journal of the Korean GEO-environmental Society
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• v.8 no.5
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• pp.47-55
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• 2007

The increment of impermeable land area due to widespread land development caused the adverse impact on urban disaster prevention because it could decrease the peak rate of runoff as well as increase the runoff and peak flow during rainy period. To date, little research has been conducted on the infiltration characteristics and quantitative analysis because of their highly dependence on construction method, paving material, surface permeability, and field condition. Hence, this study was performed to investigate the infiltration characteristics of runoff-reducing facilities according to the type of paving material, which were examined using experimental apparatus with varying paving material and rainfall intensity, and thus to provide fundamental research data for runoff-reducing infiltration facilities. In this study, the infiltration characteristics were examined under the rainfall intensity of 20, 30, 50, 80, 100, 200 mm/hr for a variety type of paving materials such as concrete, asphalt, sand, grassland, and permeable paving material. The infiltration rate for permeable paving material was observed to be more than 93% under the condition of less than 200 mm/hr of rainfall intensity. For the compacted earth and grassland, the ultimate infiltration rate was estimated to be about 13% to 67%. The permeable paving material was concluded to be the most appropriate one for the runoff-reducing infiltration facilities because it has more favorable advantages than others in the light of infiltration volume, disaster prevention, and river training.

• 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.

• Journal of Distribution Research
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• v.16 no.5
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• pp.43-61
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• 2011

In this research, we analyze about the effect of the traditional market supporting policy about 16 large unit self-governing bodies and effeciency through DEA analysis. The plan for supports of the traditional market were shown. Now, the object of the traditional market supporting policy was any more not improvement of facilities and the thing which is the attraction of customer activity for the sales increase of the traditional market could be confirmed. For the sales increase, supporting of the field like the client information center, source indicator, autonomic packing stand, and the broadcasting facility are effective more. In addition, for the visiting customer inducement activation, we could know that supporting of the field like client information center, broadcasting facility, broadcasting advertisement, and the premium event for gift certificate were required. The method including the customer distribution service operation, which is the various product development and cross sellings and client friendly based on data which it investigates the actual conditions the market merchant on the Incheon area and consumer with the concrete plan for support gift certificate activation, the market information system construction, and etc. was shown.

• Land and Housing Review
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• v.7 no.4
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• pp.323-328
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• 2016

There are small box opening for inserting of electric lamp box in the slab of apartment. Around this box opening, we normally use the detailing of WWF or plastic ring strengthening to protect cracks induced by shrinkage. The shrinkage amount of slab box around was measured and analysed in order to consider validity of these strengthening methods and to find out economical alternative. Alternative of strengthening methods are normally used strengthening methods in construction companies, which are WWF strengthening, plastic ring strengthening and no strengthening methods. The shrinkage amount was measured using contact guage at the spot of tip attached around the box on slab of small area unit apartment which have small exclusive area below $59m^2$. Measured data shows that there are no big differences between all the 3 strengthening methods and Measure data range is $-264{\mu}{\varepsilon}{\sim}+216{\mu}{\varepsilon}$. Measured shrinkage is on trend slightly increase till 3~5weeks after removal of forms and then decrease. But amount of shrinkage are very low for all the slabs and there are no probabilities of concrete crack by shrinkage.

• Journal of the Korean Institute of Rural Architecture
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• v.16 no.1
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• pp.119-127
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• 2014

This study suggests institutional and methodological approaches for preservation of South Korea's registered cultural properties of modern architecture. The suggested approaches are as follows. First, in order to improve the current registration and preservation system for cultural properties, we need to employ both structure-based classification and style-based classification. Registration criteria for modern architecture properties need to include more detailed classification in terms of their structure: brick structure, steel concrete structure and post lintel structure. In terms of construction style, the properties need to be further classified into the western style, the traditional style and the Korean-western eclectic style. In addition, protection of registered cultural properties need to be achieved through legislation of a protection system. Second, while the current system sets out six methods for preservation of registered cultural properties of modern architecture, more specific preservation methods types and plans need to be continuously introduced. In particular, as for the method of partial preservation, the method needs to be further classified based on the usage of the relevant structure so as to allow for more diverse options. First, the 'Preservation by Interior Alteration' needs to be added to the category, where the exterior is preserved as it is and the interior is preserved through alteration. Also needs to be added the preservation method where the interior space is preserved as it is and the exterior space is altered, in case the finishing materials of the exterior has deteriorated. Third, if the records on registered cultural properties of modern architecture are to provide the functions of legal evidences regarding management of architectural cultural properties, sources of knowledge required for policy making and implementation and past management record for the future, each phase needs to be closely connected in an organic manner, and we need to establish a management system and plan that go beyond the relevant organizations. Fourth, in order to preserve South Korea's registered cultural properties of modern architecture in its original state, it is imperative to prepare separate criteria for registration of technicians with expertise on modern architecture, and train experts and technicians on modern architecture, which is distinguished from the traditional architecture.

• Journal of the Korea institute for structural maintenance and inspection
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• v.16 no.6
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• pp.155-162
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• 2012

When RC (Reinforced Concrete) structures are exposed to sea water, steel corrosion can occur and this leads a degradation of structural performance. Referring the electro-deposition system with sea water from the 1st step research, durability and structural performance are evaluated in coated steel and RC members containing it in the 2nd research. In the durability performance test, Half Cell Potential test is performed and the coated steel is evaluated to have the high resistance to corrosion, which shows only 35% of corrosion velocity in normal (bare) steel. In the structural performance test, tensile strength, adhesive strength, and flexural/shear in RC member are performed. For the electro-deposit coated steel, increasing ratios of 3.2% and 8.8% are evaluated in the test of tensile strength and adhesive strength, respectively. For the structural test in RC member, there is no big difference between RC members with coated and non-coated steel in ultimate load and failure pattern It is evaluated that the chemical compound with $CaCO_3$ and $Mg(OH)_2$ from electro-deposition causes slightly increased structural performance. The electro-deposit coated steel can be more widely applied after performance verification from several tests like fatigue, resistance to impact, and long term-submerging test.

• International Journal of Highway Engineering
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• v.14 no.2
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• pp.117-129
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• 2012

Road safety audit is the preventive enhancement strategy for safety. : it gets rid of beforehand the potential factor of a traffic accident in the stage of road planning and design and it evaluates the appropriation for road geometric structure or safety facility to prevent traffic accident in the stage of operation after the construction. Since this strategy is introduced to our country in the early 2000s, various projects have been processed and it was legislated recently. And now, the evaluation of past project for its continuation is needed. Therefore, in this study the evaluation of road safety audit on existing freeway is performed. The spatial extent of this study is Yong-dong line on which the safety treatment was executed in 2005 and 2006. And, the temporal range of this study is each 2-year of before and after from 2005 and 2006. The empirical bayes method of observational evaluation studies is applied to analyze. As a result, there is an effect of improvement on most of treated sections. But there is ineffective or negligible on some sections. Compared with the detail of treatment on each section, the effect of multiple or various treatments is good for that section. On the other hand, the section on which effect doesn't appear is the result of single or unimportant treatments. Throughout these results, the concrete analysis can be performed and the countermeasures designed for the section on which effect doesn't appear. Also it is used as reference to the future plan and direction of road safety audit on existing freeway.

• Ecology and Resilient Infrastructure
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• v.3 no.2
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• pp.143-151
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• 2016

Shoreline armoring is a globally used engineering strategy to prevent shoreline erosion along stream, lake and reservoir coastlines. Armoring alters the land-water interface and has the potential to affect shoreline vegetation by changing nearshore geomorphology, hydrology, sediment composition and water quality. We quantified the effects of the artificial disturbances and alternation of the land-water interface on the community structure and distribution of shoreline vegetation in a large reservoir, Uiam Reservoir, Korea. More than 60% of shorelines were disturbed by armoring with retaining wall of concrete block, riprap and gabion in the Uiam Reservoir. The results of detrended correspondence analysis showed that the vegetation structures of the shoreline modified by armoring changed from hydrophyte-dominated to hygrophyte-dominated ecosystems. The shoreline armoring caused the disruption of gradual continuity in the water-land interface and the biological invasion by alien plants. The changes in distribution area of shoreline vegetation showed that the area of hydrophytic vegetation decreased and that of hygrophytic vegetation increased from 2010 to 2013. In conclusion, the human disturbance such as armoring, road construction, recreation etc. could lead to terrestrialization, the loss of transverse continuity and biological invasion in the shoreline vegetation of the Reservoir Uiam. Our findings suggest that redesigning or removing shoreline armoring structures may benefit nearshore hydrophytic vegetation for the conservation of novel shoreline ecosystems.