• 한국항공운항학회지
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• 제27권3호
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• pp.90-97
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• 2019

The International Civil Aviation Organization(ICAO) recently established the Global Aviation Safety Plan(GASP) for national aviation safety management, along with the enactment of Annex 19, Safety Management System(SMS). ICAO require the establishment of the 'States Safety Programs(SSP)' for countries with excellent safety evaluation, including Korea, and the establishment of aviation safety supervision systems for all Contracting States by 2017 under the enactment of ICAO Annex 19. Required. The Ministry of Land, Infrastructure, and Transport has continuously invested in R&D to secure such aviation safety systematically, and is making efforts to develop and disseminate related technologies by establishing long-term R&D roadmaps. A study on aviation safety supervision among the system-based aviation safety supervision support technology development R&D project, which is underway as part of the aviation safety technology development project of the Ministry of Land, Infrastructure and Transport. We conducted a study to see if this methodology logically guarantees reasonableness.

• International journal of advanced smart convergence
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• 제10권2호
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• pp.158-167
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• 2021

Fishery industry is an important part of agricultural industry in coastal countries. The purpose of this study is to use the theory of industrial competitiveness for reference, use Analytic Hierarchy Process (AHP) and Delphi method to establish the evaluation index system, and analyze the fishery industry competitiveness of 11 coastal provinces in China. This study data came from China Fishery Statistical Yearbook 2020. The results show that Shandong Province is the most competitive province in fishery industry among the coastal provinces. The inter-provincial differences are great. Not only the resource endowment is the factor that affects the fishery industry competitiveness, but also the long-term profitability is too. The proportion of recreational fishery in the fishery economic output value has become one of the main indicators to measure the competitiveness of the fishery industry. The findings of this study suggest that all regions should adopt measures in accordance with local conditions, promote the integrated development of the fishery industry, enhance the added value of fishery products and enhance the competitiveness of fishery industry. The disadvantage of this study is that the fishery industry competitiveness of China's coastal provinces is only compared and analyzed. The future direction is to carry out a comparative study on the international competitiveness of fishery with other east Asian countries.

• International Journal of Internet, Broadcasting and Communication
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• 제14권1호
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• pp.152-161
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• 2022

Recently, it is recognized as a high-cost and inefficient logistics system that increases traffic congestion and environmental problems due to an increase in traffic volume due to the activation of the online market. In order to solve inefficient problems such as unavoidable traffic congestion and environmental problems caused by the increase in traffic volume, it is necessary to develop a freight transport system technology using the existing urban railway infrastructure and freight-only urban railway. The urban subway logistics system is a logistics system that requires a combination of various technologies to solve the nationwide demand for urban logistics and road traffic problems. This paper recognized the existing traffic congestion and environmental pollution of road traffic as problems, and supplemented the contact point requirements presented above by identifying the sub-systems constituting the target system and supplementary points for each part-level contact point. In this study, as a complex system operated for one purpose by grafting various technologies, a plan is required to secure the reliability and safety of operation from various viewpoints. The results of this study can contribute to the initial configuration and basic data to solve the interface bottleneck of the urban subway logistics system to be promoted in the future.

• 한국항해항만학회지
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• 제32권1호
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• pp.97-102
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• 2008

선박의 대형화 및 해상사업의 기업화 등에 따라 해상운송에 있어 화물의 하역, 보관 등의 전문적인 부분을 담당하고 있는 항만하역업자, 항만터미널운영자, 창고업자 등 독립계약자의 역할은 점점 증대되어 가고 있는 추세이다. 하지만 국제해상운송은 해상운송인과 화주를 중심으로 체결한 운송계약을 중심으로 이루어져 왔으므로, 영국 보통법상의 직접계약관계의 원칙에 의해 계약당사자가 아닌 자는 계약상의 이익을 원용할 수 없다는 입장을 유지하여 왔다. 이에 대해 이를 완화하고자 하는 다양한 방안이 적용되고 있으며, '히말라야약관'도 그러한 방안중의 하나이다. 본 논문은 최근 대법원판결을 통해 우리나라 법원의 히말라야약관의 유효성 인정에 대한 내용을 재검토하고 독립계약자, 특히 항만터미널운영자의 운송계약상 제3자의 권리인정에 관한 문제에 대한 각국의 경향에 대해 살펴본다.

• 방송공학회논문지
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• 제25권2호
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• pp.252-264
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• 2020

2017년 5월 31일 세계 최초로 우리나라에서 지상파 UHD 방송이 상용화되었다. 기존 HDTV 방송은 압축된 미디어와 부가 데이터를 다중화하여 전달하기 위해 MPEG-2 TS(Transport Stream) 표준을 사용하였으나, 지상파 UHD 방송 규격에서는 차세대 표준인 MMT(MPEG Media Transport)가 채택되었다. 그러나 UHD 콘텐츠 제작 비용이 고가이므로, 현재 전체 방송시간 중 일부만 UHD로 방송되고 있으며 점차로 그 시간을 증가시켜 가고 있는 중이다. 한편 MMT가 채택된 ATSC 3.0 표준의 경우에도 북미에서 본격적인 상용화 단계에 이르지 못하고 있다. 이로 인해 MMT 방송 장비는 아직도 고가의 초기 단계에 있다. 본 논문에서는 기존 MPEG-2 TS 다중화기의 출력을 입력으로 받아 MMTP(MMT Protocol) 패킷 스트림으로 변환하는 저렴한 장비를 개발하는 데에 활용할 수 있는 소프트웨어를 다중 쓰레드(multi-thread) 기반으로 일반 PC 상에서 구현하고 그 기능을 실험을 통해 검증하였다.

• Journal of the korean society of oceanography
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• 제39권1호
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• pp.96-106
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• 2004

A total of 116 surface sediment samples were obtained on the Yellow Sea and analyzed for grain size and geochemical elements in order to interpret the present sediment transportation. Thirty-nine cores and 3,070 line-km shallow seismic profiles are analyzed for sedimentary records of Yellow Sea in the past. Results show that the boundary of sediment transport between Korean side and Chinese side is about between $123^{\circ}E$ and $124^{\circ}E$. The similar result is produced from Shi et al. (in this publication). Two cyclonic patterns of surface sediments are recognized in the northeastern and southwestern Yellow Sea, while the strong front zone of the mud patch and sandy sediments are found in the southeastern Yellow Sea (the southwestern part of Korean coasts). The formation of fine-particle sediment packages, called for Northwest Mudbelt Deposit (NWMD), Hucksan Mudbelt Deposit (HSMD) and Jeju Mudbelt Deposit (JJMD), are resulted from eddies (gyres) of water circulations in the Yellow Sea. NWMD has been formed by cyclonic (anticlockwise) eddy. NWMD is composed of thick, homogeneous, relatively semi-consolidated gray clay-dominated deposit. On the other hand, HSMD and JJMD are formed by anticyclonic (clockwise) eddies. They are thick, homogeneous, organic-rich gray, silt-dominated deposit. Both core and surface sediments show that the middle zone across Chinese and Korean side contains bimodal frequency of grain-size distribution, indicating that two different transport mechanisms exist. These mud packages are surrounded by sand deposits from both Korea and China seas, indicating that Yellow Sea, which is the shallow sea and epicontinental shelf, is formed mostly by sand deposits including relict sands. The seismic profiles show such as small erosional/non-depositional channels, sand-ridges and sand-waves, Pleistocene-channelfilled deposits, a series of channels in the N-S major channel system, and thick Holocene sediment package, indicating that more complex sedimentary history exists in the Yellow Sea.

• Structural Engineering and Mechanics
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• 제49권4호
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• pp.427-448
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• 2014

At present, the time of easy oil and gas is over. Now, the largest part of fossil fuels is concentrated in the deepest levels of tectonic structures and in the sea shelves. One of the most cumbersome operations of their extraction is the bore-hole drilling. In connection with austere tectonic and climate conditions, their drivage every so often is associated with great and diversified technological difficulties causing emergencies on frequent occasions. As a rule, they are linked with drill string accidents. A key role in prediction of these situations should play methods of theoretical modelling. For this reason, there is a growing need for development and implementation of new numerical methods for computer simulation of critical and post-critical behavior of drill strings (DSs). In this paper, the processes of non-linear deforming of a DS in cylindrical cavity of a deep bore-hole are considered. On the basis of the theory of curvilinear flexible rods, non-linear constitutive differential equations are deduced. The effects of the longitudinal non-uniform preloading, action of torque and interaction between the DS and the bore-hole surface are taken into account. Owing to the use of curvilinear coordinates in the constraining cylindrical surface and a specially chosen concomitant reference frame, it became possible to separate the desired variables and to reduce the total order of the equation system. To solve it, the method of continuation the solution by parameter and the transfer matrix technique are applied. As a result of the completed numerical analysis, the critical states of the DS loading in the cylindrical channels of inclined bore-holes are found. It is shown that the modes of the post-critical deforming of the DS are associated with its irregular spiral curving prevailing in the zone of bottom-hole-assembly. The possibility of invariant state generation during post-critical deforming is established, condition of its bifurcation is formulated. It is shown that infinite variety of loads can correspond to one geometrical configuration of the DS. They differ each from other by contact force functions.

• 한국의류산업학회지
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• 제17권3호
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• pp.462-475
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• 2015

This paper investigated the characteristics of the physical properties of woven fabrics according to the yarn structure and fibre property. It was found that wicking property of woven fabrics made of sheath/core hybrid yarn were better than those of siro spun and siro-fil hybrid yarns, which was caused by platform for transport of moisture vapor by filaments on the core part of sheath core hybrid yarns. In drying property, the fabric specimen woven by PP/Tencel sheath core hybrid yarns as a warp and Coolmax/Tencel spun yarn as a weft showed quick drying property, which was caused by the sheath core hybrid yarn structure as drainage of water moisture and coolmax fibre characteristics as quick dry material. Concerning to breathability and thermal conductivity as heat transport phenomena, it was observed that breathability of fabrics woven with hybrid yarns such as sheath core and siro-fil in the warp and hi-multi filaments in the weft showed the lowest water vapor resistance, which was explained as due to for air gap in the fibres of the spun yarns to restrict the wet heat transport from perspiration vapor. Thermal conductivities of the fabrics woven with PET/Tencel siro-fil yarns in the weft and hybrid yarns such as sheath core and siro-fil in the warp revealed the highest values, which was observed as due to higher thermal conductivity of PET than PP and more contact point between fibres in the siro-fil and sheath core hybrid yarns.

• 해양환경안전학회지
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• 제12권4호
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• pp.285-291
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• 2006

소리도와 욕지도 사이 해역의 유동 분포를 파악하기 위하여 2004년 5월, 6월, 10월 및 11월에 ADCP를 이용하여 정선관측 및 정점관측을 실시하였다. 25시간 정선관측에 따른 평균류의 연직분포는 욕지도 남서해역에서 북동류의 흐름이 우세하게 나타났다. 또한 25시간 정점관측 결과를 보면 상층과 하층의 경계수심이 $15\sim20m$에 존재함을 알 수 있었고, 상 하층으로의 유동분포가 다르고 상층과 하층의 변화폭이 작게 나타났다. 동서 성분 및 남북 성분에 대판 해수 수송량의 계산결과는 남서방향으로의 수송량보다 북동방향으로의 수송량이 더 크게 나타났다.

• 한국환경과학회지
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• 제25권1호
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• pp.107-125
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• 2016

Long-term variations of $PM_{10}$ and the characteristics of local meteorology related to its concentration changes were analyzed at 4 air quality sites (Ido-dong, Yeon-dong, Donghong-dong, and Gosan) in Jeju during two different periods, such as PI (2001-2006) and PII (2007-2013), over a 13-year period. Overall, the long-term trend of $PM_{10}$ was very slightly downward during the whole study period, while the high $PM_{10}$ concentrations in PII were observed more frequently than those in PI. The concentration variations of $PM_{10}$ during the study period was clarified in correlation between $PM_{10}$ and meteorological variables, e.g. the low (high) $PM_{10}$ concentration with large (small) precipitation or high (low) radiation and in part high $PM_{10}$ concentrations (especially, Donghong-dong and Gosan) with strong wind speed and the westerly/northwesterly winds. This was likely to be caused by the transport effect (from the polluted regions of China) rather than the contribution of local emission sources. The $PM_{10}$ concentrations in "Asian dust" and "Haze" weather types were higher, whereas those in "Precipitation", "Fog", and "Thunder and Lighting" weather types were lower. The contribution of long-range transport to the observed $PM_{10}$ levels in the urban center (Ido-dong, Yeon-dong, and Donghong-dong), if estimated by comparison to the data of the background site (Gosan), was found to explain about 80% (on average) of its input.