• Title/Summary/Keyword: Ground current

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Power Save of Marine Tracker Buoy System Based on NB-IoT for Identification of Fishing Gear (어구 자동 식별을 위한 NB-IoT 기반의 해양 트래커 부이 시스템의 전력 절감)

  • Nam, Sung-Il;Kim, Min-Hoon
    • Journal of Advanced Navigation Technology
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    • v.22 no.6
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    • pp.545-550
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    • 2018
  • Ministry of Oceans and Fisheries declared action plan for the electric fishing gear using real name in order to prevent overusing the fishing gear and to reduce discarded fishing gear. It is needed for a technique that can efficiently transmit the information including the type and location of the fishing gear and the user's real name to the fishing boat and the control center using IoT-based communication. The marine tracker buoy system, which is placed on the water for a long time, transmit the position data and the state data of the buoys to the control center in the ground by using NB-IoT channels. In this paper, we propose the algorithm for the low-power operation of the marine tracker buoy system is proposed and test results of current consumption in the marine tracker buoy system with the proposed algorithm is investigated.

Review on Current Status on Mine Reclamation Policies of 9 Countries represented by International Symposium (광해방지 국제심포지엄 발표사례로 본 국가별 광해 및 복구현황과 정책)

  • Lee, Seung Ah;Yang, In Jae
    • Journal of the Korean Society of Mineral and Energy Resources Engineers
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    • v.55 no.6
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    • pp.546-552
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    • 2018
  • Although there are differences in the history of mining development by country, geographical conditions, and economic status, there are various problems such as water pollution caused by acid mine drainage from past mine development, soil and water pollution caused by mine tailing, and landslides caused by slope failure. Thus, human life is threatened by ground subsidence caused by collapses. Some countries have technology and legal systems that are different from those of others. In countries where mine reclamation is underway, or has to begin, there is a need for institutional arrangements and technical support. Countries trying to start mine reclamation require help from the international community. Technically and institutionally advanced nations need to recover from mine reclamation through cooperation with countries that are beginning to undertake reclamation.

A Review on the Hazards of Flavoring Chemicals in Coffee Roasting Proces (커피 로스팅 공정에서 발생되는 향기물질의 유해성 고찰 및 노동자 건강보호 방안)

  • Rim, Kyung-Taek
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.29 no.2
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    • pp.119-140
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    • 2019
  • Objectives: This study was based on the occurrence of a coffee roasting process-related disorder(bronchiolitis obliterans; published by NIOSH in the US) among workers exposed to chemicals called diacetyl in a coffee processing facility. Flavorings added to coffee contain diacetyl and 2,3-pentanedione, all of which are subject to exposure in a number of food manufacturing processes, including coffee roasting, grinding, and packaging. Therefore, this study aims to review the toxicity to workers related to food processing and food additive manufacturing to prevent occupational diseases. Methods: We surveyed the related literature, domestic and international references, and the status of relevant domestic and foreign professional organizations. The present situation of workers was investigated by reviewing literature on the safety and health of workers in the coffee roasting process using domestic and foreign literature and presentations. Expert advisory opinions were reflected, and experts were consulted by participating in domestic and overseas academic conferences. Results: Most of the fragrance materials for coffee were harmful and hazardous substances according to the GHS classification, and research was carried out through a second external consultation. A literature review on the measurement of air pollutant emissions from coffee roasters and the estimation of air pollutant emissions during coffee roasting examined the characteristics of pollutants emitted during coffee roasting. Conclusions: Two chemicals identified as causing bronchiolitis obliterans in the coffee roasting process are believed to explain why the disease is difficult to treat. This information can be used effectively in the future prevention of this disease. Future studies should clearly identify the potential for toxicity of alpha-diketones and the bases of OELs in relation to the occurrence of obstructive bronchiolitis, including measurement of various organic compounds and alpha-diketones from ground coffee, as well as various coffee grinds and coffee bean varieties. In particular, it is necessary to clarify the current understanding of the dose-response relationship between alpha-diketone and lung disease in workers involved in coffee roasting.

A research on the stone ornaments of Taesils of Joseon royal family (조선왕실(朝鮮王室)의 태실석물(胎室石物)에 관한 일연구(一硏究) -서삼릉(西三陵) 이장(移藏)원 태실(胎室)을 중심(中心)으로-)

  • Yun, Seok-In
    • Korean Journal of Heritage: History & Science
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    • v.33
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    • pp.94-135
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    • 2000
  • Rituals for burying the tae(胎) is a unique royal tradition of Korea that lasted from Unified Shilla(統一新羅) Kingdom to Joseon(朝鮮) dynasty. However, all of the currently known taesil(胎室)s are of the royal descendants of Joseon dynasty. Therefore, Taesils made earlier than Joseon dynasty are only known by historical documents. Taesils of the royal descendants of Joseon Dynasty divide into two kinds. One is for those of princes and princesses and the other is for those of Kings. The structure of taesils of princes and princesses is a stone chest(石函) in a pit which dug on the apex of the Taebong(胎峰) containing a pair of Tae(胎)-urn(the inner urn and outer urn), a stone tablet called Jiseok(誌石) which the date of baby's birth and Tae burial is inscribed in. And a tombstone-shaped stone tablet which called Taesilbi(胎室碑) was built on the ground. And the underground structure of Taesils of Kings is identical with that of taesils of princes and princesses, but instead of just an stone tablet, this has a Budo(浮屠);means stupa of a monk in korean)-shaped stone structure on the top of the stone chest, and an octagon-shaped porch was built around it, and a Tapbi(塔碑) was built. This treatise is focused on the current status and change process of stone ornaments. The subject of this treatise is 54 Taesils which were transferred to Seosamnung(西三陵) during the japanese occupation and Tae-urns and Jiseok(誌石)s from any other Taesil and its stone chest were not included in this treatise. Researches on Taesils can be great help to history by providing resources about genealogy of Jaseon royal family and social, economical status of that time. And researches on stone ornaments and tae-urns from Taesils can provide great help to stone art history and porcelain history of Joseon dynasty.

Vascular plant diversity of the Gogunsan Archipelago in the Korean Peninsula

  • Kim, Jung-Hyun;An, Ji-Hong;Nam, Gi-Heum;Park, Hwan-Joon;Kim, Jin-Seok;Lee, Byoung Yoon;Lee, Kyeong-Ui;Chang, Yeon-Soon
    • Journal of Species Research
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    • v.8 no.1
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    • pp.136-159
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    • 2019
  • This study was carried out to investigate the flora of six islands belonging to the Gogunsan Archipelago (i.e., Sinsi-do, Seonyu-do, Munyeo-do, Yami-do, Bian-do, and Duri-do) in the Korean Peninsula. As results of five field surveys from March to October of 2016, we have identified 575 total taxa, representing 527 species, five subspecies, 42 varieties, and one hybrid, placed in 358 genera and 118 families. Of these 575 taxa, four are endemic to Korea, six taxa are listed on the Korean Red List of threatened species, 67 are floristic regional indicator plants, and 74 are invasive alien species. In this study, we compared species richness among the islands, and find that the larger the islands, the higher the species richness. In the case of habitat affinity types, forest species were most common, followed by farmland, seacoast, bare ground and wetland species. From similarity analyses based on the composition of vascular plants, each island did not exhibit either local specificity or unique diversity. On the contrary, the proportion of invasive alien and ruderal species may increase by human activities. Investigations and analyses of island flora such as this are important to assess the current status of the flora, predict future vegetation patterns and the spread of the alien species, and establish managment plans of plant diversity.

Optimal tree location model considering multi-function of tree for outdoor space - considering shading effect, shielding, openness of a tree - (옥외공간에서 수목의 다기능을 고려한 최적의 배식 위치 선정 모델 - 수목의 그림자 효과, 시야차단, 개방성을 고려하여 -)

  • Park, Chae-Yeon;Lee, Dong-Kun;Yoon, Eun-Joo;Mo, Yong-Won;Yoon, June-Ha
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.22 no.2
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    • pp.1-12
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    • 2019
  • Open space planners and designers should consider scientific and quantified functions of trees when they have to locate where to plant the tree. However, until now, most planners and designers could not consider them because of lack of tool for considering scientific and quantitative tree functions. This study introduces a tree location supporting tool which focuses on the multi-objective including scientific function using ACO (Ant colony optimization). We choose shading effect (scientific function), shielding, and openness as objectives for test application. The results show that when the user give a high weight to a particular objective, they can obtain the optimal results with high value of that objective. When we allocate higher weight for the shading effect, the tree plans provide larger shadow value. Even when compared with current tree plan, the study result has a larger shading effect plan. This result will reduce incident radiation to the ground and make thermal friendly open space in the summer. If planners and designers utilize this tool and control the objectives, they would get diverse optimal tree plans and it will allow them to make use of the many environmental benefits from trees.

Improving Information Service for Earthquake Using Rapid ShakeMap

  • Hwang, Jinsang;Ha, Ok-Kyoon
    • Journal of the Korea Society of Computer and Information
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    • v.26 no.5
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    • pp.95-101
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    • 2021
  • In this study, we present how to improve the current seismic disaster information service by utilizing Shake, which can express the effects of earthquakes in the form of isolines. Using ShakeMap software provided by the U.S. Geological Survey, an automated rapid ShakeMap generation system was implemented, and based on this, an earthquake disaster information service improvement model was presented to identify earthquake risk in the form of intensity or peak ground acceleration. In order to verify the feasibility and effectiveness of the improved model, the seismic disaster information service app. was developed and operated on a trial basis in Pohang, Gyeongsangbuk-do. As a result of the operation, it was found that more detailed seismic risk information could be provided by providing information using rapid ShakeMap to induce users' safety behavior more effectively.

The Occurrence and Treatment Status of Off-site Contaminated Soils in Korea (국내 오염토양 반출정화사업 현황)

  • Han, SuHo;Jung, MungChae;Kim, JeongWook;Jeon, SoonWon;Nguyen, Quoc Tuan;Yoon, KyungWook;Min, SeonKi
    • Journal of Soil and Groundwater Environment
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    • v.25 no.4
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    • pp.1-6
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    • 2020
  • Recently, ex-situ remediation technologies has been emerging to clean up contaminated soils mainly because the in-situ techniques have limited applicability and technical difficulties in relatively small contaminated sites. Accordingly, implementation of off-site treatment and disposal have been continuously increased in soil remediation and restoration projects in Korea. However, in many cases, reclaimed soil is still not properly recycled or reused. Therefore, there is an urgent need to document the current status of soil management practices in soil remediation projects in the nation. This study presents a survey of soil contamination status and remedial approaches in Korea based on soil cleanup projects completed in 2015 - 2019, and proposes the possible options of the recycling or reusing the reclaimed soils under compliance with related regulations. The results of the soil survey showed soil contamination was most severe in gas stations, industrial facilities, and military areas. The major types of pollution were related to the petroleum-contaminated site (TPH and BTEX) with 77.0% occurrence in all the contaminated sites. The reclaimed soils were mostly reused as a ground filling-up soils in industrial facilities (60.0%) and warehouses (37.0%).

Design and Implementation of Mobile 3D Visualization Service System on the Integrated Underground Geospatial Information Map

  • Cho, Sook-Kyoung;Kim, Yong-Tae;Choi, Ja-Young
    • Journal of the Korea Society of Computer and Information
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    • v.25 no.12
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    • pp.173-186
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    • 2020
  • In this paper, we design and implement a service system for mobile devices to utilize the integrated underground geospatial information map in underground exploration fields. The field utilization service system for mobile devices is designed to visualize tiled maps, 3D terrain information, underground structures, underground facilities, and ground information provided by the Integrated Underground Geospatial Information Map Management System according to current position. And It is designed to reflect the results obtained from field exploration in real time. Also, the proposed system is implemented to transfer and visualize the integrated underground geospatial information map in the form of a glTF format due to constraints on wireless networks and device characteristics of mobile devices. Implemented mobile service systems can prevent accidents in underground exploration field from occurring by providing users with accurate and integrated underground geospatial data by visualizing maps and geospatial objects in three dimensions at underground exploration fields. In addition, updated underground geospatial data is transmitted in real time to the Integrated Underground Geospatial Information Map Management Systems, which can maintain up to date and accuracy.

Seismic analysis of high-rise steel frame building considering irregularities in plan and elevation

  • Mohammadzadeh, Behzad;Kang, Junsuk
    • Steel and Composite Structures
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    • v.39 no.1
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    • pp.65-80
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    • 2021
  • Irregularities of a building in plan and elevation, which results in the change in stiffness on different floors highly affect the seismic performance and resistance of a structure. This study motivated to investigate the seismic responses of high-rise steel-frame buildings of twelve stories with various stiffness irregularities. The building has five spans of 3200 mm distance in both X- and Z-directions in the plan. The design package SAP2000 was adopted for the design of beams and columns and resulted in the profile IPE500 for the beams of all floors and box sections for columns. The column cross-section dimensions vary concerning the number of the story; one to three: 0.50×0.50×0.05m, four to seven: 0.45×0.45×0.05 m, and eight to twelve: 0.40×0.40×0.05 m. Real recorded ground accelerations obtained from the Vrancea earthquake in Romania together with dead and live loads corresponding to each story were considered for the applied load. The model was validated by comparing the results of the current method and literature considering a three-bay steel moment-resisting frame of eight-story height subject to seismic load. To investigate the seismic performance of the buildings, the time-history analysis was performed using ABAQUS. Deformed shapes corresponding to negative and positive peaks were provided followed by the story drifts and fragility curves which were used to examine the probability of collapse of the building. From the results, it was concluded that regular buildings provided a seismic performance much better than irregular buildings. Furthermore, it was observed that building with torsional irregularity was more vulnerable to seismic failure.