• Journal of the Korean Society for Aviation and Aeronautics
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• v.11 no.2
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• pp.79-92
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• 2003

This study is to identify the hazard of ozone and to evaluate ozone effect that is flowed into the cabin when the airplane is flying at high altitude. For this purpose, it is studied that how ozone is generated in the air, what the effect on human body is due to the cabin ozone and what the design criteria is considering or preventing the ozone hazard. And, finally the regulations and means of compliance are studied and introduced to assure that the aircraft satisfies the design criteria related to ozone.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.25 no.4
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• pp.426-433
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• 2014

The high-altitude electromagnetic pulse(HEMP) generated by a high-altitude nuclear explosion. This paper presents the comparison of electric field penetration in Bell laboratories and IEC 61000-2-9 standard when HEMP source penetrates through Naval Warship conducted coupling path and radiated coupling path. Also we analyze the effects of two kinds of coupling and propose Protective measures. Simulation results confirm IEC 61000-2-9 standard is more strict than the Bell Laboratories standard except for a lower frequency band, so we proposed IEC 61000-2-9 standard as a Naval HEMP standard. Finally, we offer the protective measures such as the shielding coating, Honeycomb ventilation, TVS in order to meet the military criteria.

• Journal of the Korea Concrete Institute
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• v.29 no.2
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• pp.169-177
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• 2017

Rather than causing damage from heat, blast, and radiation of a regular nuclear weapon, recently, it is predicted that North Korea has been inventing high altitude electromagnetic pulse (HEMP) missile in order to incapacitate electronic equipment. HEMP shielding facility is used for military purpose today. Despite the electromagnetic shielding effects from high quality compression plates, problems may include such as the possibility of electromagnetic influx resulting in the welding of the compression plates, and difficulties and high cost of construction. Therefore, in this study, a high electrical conducting material was added to the concrete experimental subject to ensure the shielding effect through electromagnetic waves to for the concrete structure, instead of building a shielding facility separately for the structure. Also, among the experimental subjects, 100 ${\mu}m$ of Iron-Aluminum alloy metal spraying coat was applied to two types with the highest shielding effect, and to two types with the lowest shielding effect. The result of the experiment indicates that experimental subjects added with a high electrical conductivity material did not meet the minimum shielding criteria of MIL-STD-118-125-1 standard, but all the experimental material applied to the metal spraying coating satisfied the minimum shielding criteria. In conclusion, it is considered that 100 µm of Iron-Aluminum alloy metal spraying coat contains high efficiency in the HEMP shielding.

• Journal of Computational Design and Engineering
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• v.3 no.1
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• pp.37-52
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• 2016

To injection mould polymers, designing mould is a key task involving several critical decisions with direct implications to yield quality, productivity and frugality. One prominent decision among them is specifying sprue-bush conduit expansion as it significantly influences overall injection moulding; abstruseness anguish in its design criteria deceives direct determination. Intuitively designers decide it wisely and then exasperate by optimising or manipulating processing parameters. To overwhelm that anomaly this research aims at proposing an ideal design criteria holistically for all polymeric materials also tend as a functional assessment metric towards perfection i.e., criteria to specify sprue conduit size before mould development. Accordingly, a priori analytical criterion was deduced quantitatively as expansion ratio from ubiquitous empirical relationships specifically a.k.a an exclusive expansion angle imperatively configured for injectant properties. Its computational intelligence advantage was leveraged to augment functionality of perfectly injecting into an impression gap, while synchronising both injector capacity and desired moulding features. For comprehensiveness, it was continuously sensitised over infinite scale as an explicit factor dependent on in-situ spatio-temporal injectant state perplexity with discrete slope and altitude for each polymeric character. In which congregant ranges of apparent viscosity and shear thinning index were conceived to characteristically assort most thermoplastics. Thereon results accorded aggressive conduit expansion widening for viscous incrust, while a very aggressive narrowing for shear thinning encrust; among them apparent viscosity had relative dominance. This important rationale would certainly form a priori design basis as well diagnose filling issues causing several defects. Like this the proposed generic design criteria, being simple would immensely benefit mould designers besides serve as an inexpensive preventive cliché to moulders. Its adaption ease to practice manifests a hope of injection moulding extremely alluring polymers. Therefore, we concluded that appreciating injectant's polymeric character to design exclusive sprue bush offers a definite a priori advantage.

• Journal of the Korea Institute of Military Science and Technology
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• v.10 no.4
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• pp.81-87
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• 2007

In this study, analysis of structural design criteria for the canopy actuating device has been conducted considering the aerodynamic breakaway capabilities of jettisonable canopy system. Unsteady aerodynamic loads for the opened canopy configuration at passively controlled jettision mode were computed using CFD method. The general purpose multi-body finite element code, SAMCEF Mecano, is used in the implemented analyses for the passive jettision condition. The recommended altitude and speed of aircraft was suggested as design criteria of aerodynamic breakaway capability of jettisonable canopy system as a bakup egress method when normal canopy jettison sequence malfunctioned. Aerodynamic breakaway condition of jettisonable canopy was also simulated and the fracture load conditions of canopy actuator were investigated.

• Journal of Environmental Impact Assessment
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• v.7 no.1
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• pp.49-61
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• 1998

Zoning areas within national parks in Korea are classified into Natural Preservation Zone(NPZ). Natural Environment Zone(NEZ), Settlement Zone(SZ) and Mass Facility Zone(MFZ) based on the Natural Park Act Large-scale development which might cause permanent destruction of natural resources are being done in NEZ which covers 90% of the total natural park area. Thus it is necessary to examine National Park Act which refers the authorized criteria and development activities of NEZ. However, the current environmental impact statement(EIS) does not cover the full impact of the development inside the national park area. Based on these concepts, the study examines the appropriate resources to distinguish the NPZ and NEZ in Mt. Teogyu National Park, then compare the distribution of resource characteristics between two area by using GIS. Through this study, the conclusions are as follows; (1) In terms of scenic resource analysis, the current NPZ does not meet the criteria on the National Park Act Rather, most of the resources which should be located within the NPZ are located within the NEZ. (2) In terms of elevation analysis, Mt. Teogyu National Park, most of NPZ are located on high altitude which is more than l,200m above the mean sea level. Therefore, it shows the elevation is the only criteria for distinguishing NPZ and NEZ. (3) In terms of Degree of Green Naturality(DGN), the second forest areas, the eighth grade of DGN in Mt. Teogyu National Park are distributed much more in the NEZ than NPZ. (4) After examining five factors - scenic resources, elevation, slope and DGN, vegetation- it was found out that zoning of Mt. Teogyu National Park is not adequatly designated. Zoning of national parks should be accomplished based on the precise inventory of the current resources.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.18 no.3
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• pp.109-118
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• 2015

This study was performed to propose the site selection plan for the restoration of the target Reeve's turtle (Maunemys reevesii) habitat and has developed the AHP model to select the optimal site for Reeve's turtle habitat restoration on the basis of the Reeve's turtle Habitat Suitability Index (HSI) items (factors and variables). The assessment areas were established by the Reeve's turtle HSI factors such as breeding space, feed, cover, water, threatening factors and others and the sub-assessment items by each assessment area were established based on the Reeve's turtle HSI variables. The weighting values of the assessment areas and items were calculated by the developed AHP method. The weighting values of the 5 assessment areas were arranged in order as breeding space(0.293), food(0.273), water(0.217), cover(0.113), and threatening factor(0.104). The final weighting values of the 17 assessment items were arranged in order of height as all kind of food(0.222), water depth(0.096), altitude of spawning ground(0.093). The scoring criteria according to the assessment items and factors were marked and applied by equal intervals considering the criteria by HSI items of the Reeve's turtle and finally the scoring criteria diagram as been proposed for the optimal site selection of the Reeve's turtle habitat restoration.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2016.10a
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• pp.20-21
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• 2016

In this study, the shielding properties of concrete with conductive materials as shielding material for electromagne- tic pulse(EMP) within 10kHz~18GHz were investigated. The shielding effectiveness of specimens were compared with different entrained materials. The shielding effectiveness were determined according to MIL-STD-188-125-1, IEEE-STD-299 at 28 days of concrete curing. The results of shielding effectiveness did not meet the criteria(80dB) severely.

• Korean Journal of Soil Science and Fertilizer
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• v.40 no.3
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• pp.221-228
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• 2007

Quantitative analysis of distribution characteristics of soils in Jeju Island was conducted by using geographic information system (GIS) technology. Soil series could be classified 5 groups after cluster analysis with proximity ratios among soil series which mean ratios of boundary lengths of other soils to total boundary length. Classification with proximity only was similar to conventional classification system at detailed soil map although conventional system was made from several criteria such as soil color, altitude and chemical characteristics of soils. Altitudinal sequence of soil series was also suggested from representative altitudes of them which could be found from areal distribution curve along altitudes. The sequence was brown forest soils - black soils - very dark brown soils - dark brown soils from the peak of Halla Mt. to the coast on all sides, which maybe related to pedogenesis process in Jeju Island.

• Journal of the Korean Institute of Landscape Architecture
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• v.38 no.5_2
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• pp.163-175
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• 2010

This study is based on the viewing characteristics of mountain landscapes. It investigates whether the current landscape management-related regulations are efficient in terms of the viewing characteristics of the mountain landscape against Bukhansan Mountain in which the conventional landscape management techniques were used. In addition, some viewing characteristics of mountain landscapes, such as distance from the view point to the target mountain, angle of elevation, altitude, gradient, have been analyzed and 3 cases of viewing condition have been simulated. The following results were obtained: i) Mountain landscapes can be managed up to 7~8 times of the mountain height with a $5{\sim}9^{\circ}$ of elevation angle. ii) In the Natural Landscape District which is situated on the hillside, it is reasonable to include altitude, gradient as criteria for regulation. iii) According to a simulation of the construction permit height by viewing distance, it was confirmed that buildings can be constructed up to 111.55m when viewing the 20% ridge, 150.75m when viewing the 50% ridge and 189.05m when viewing the 70% ridge. iv) The construction permit height varies depending on the landscape analysis method that is used and the application conditions. It is therefore unfair to apply height limit regulations to all buildings without considering the geographical features or viewing characteristics. v) It is unreasonable to apply 2~3 management techniques to the same area for landscape management. Therefore, we recommend the Focused Landscape Management Area based on the landscape master plan as a integrating mountain landscape management techniques.