• International Journal of Fluid Machinery and Systems
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• v.10 no.2
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• pp.146-153
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• 2017

Sediment flow through hydropower components causes hydro-abrasive erosion resulting in loss of efficiency, interruptions in power production and downtime for repair/maintenance. Online instruments are required to measure/capture the variations in sediment parameters along with collecting samples manually to analyse in laboratory for verification. In this paper, various sediment parameters viz. size, concentration (TSS), shape and mineral composition relevant to hydro-abrasive erosion were measured and discussed with respect to a hydropower plant in Himalayan region, India. A multi-frequency acoustic instrument was installed at a desilting chamber to continuously monitor particle size distribution (PSD) and TSS entering the turbine during 27 May to 6 August 2015. The sediment parameters viz. TSS, size distribution, mineral composition and shape entering the turbine were also measured and analysed, using manual samples collected twice daily from hydropower plant, in laboratory with instruments based on laser diffraction, dynamic digital image processing, gravimetric method, conductivity, scanning electron microscope, X-ray diffraction and turbidity. The acoustic instrument was able to capture the variation in TSS; however, significant deviations were found between measured mean sediment sizes compared to values found in the laboratory. A good relation was found for turbidity ($R^2=0.86$) and laser diffraction ($R^2=0.93$) with TSS, which indicated that turbidimeter and laser diffraction instrument can be used for continuous monitoring of TSS at the plant. Total sediment load passed through penstock during study period was estimated to be 15,500 ton. This study shall be useful for researchers and hydropower managers in measuring/monitoring sediment for hydro-abrasive erosion study in hydropower plants.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.21 no.7
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• pp.1364-1370
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• 2017

This paper proposes a method that automatically sets profile schedule context-based mobile phone by collecting the user's external situation based on the GPS sensor and accelerometer built into the smartphone and interacting with the data in the user's schedule to minimize the user's handset handling. However, real-time data collection in mobile phones causes energy shortage in the device due to battery consumption. In other words, a service control method is explained in a way that can efficiently handle resource consumption because accessing a measurement device such as GPS and other sensors may increase power consumption of the portable device. Therefore, effective data sharing for context awareness to reduce weekly schedules and smartphone mode has improved energy efficiency in sensing for data collection. The user can use the context more effectively by providing environmental adaptability for various situations such as the end user's local context and smartphone force control.

• 한국신재생에너지학회:학술대회논문집
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• 2011.05a
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• pp.222-222
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• 2011

Plastic product is increasing by the growth of its demand and most of refused plastics are incinerated or reclaimed. However, the refused plastic is not easily decomposed and has the environmental problem with its various toxic gas in case of incineration. Therefore, many countries such as USA, Japan, Germany and other developed industrial countries as well as Korea are interested in studying the recyclable resource of refused plastic. The macromolecular waste pyrolysis has the advantage of collecting of raw materials in high price and can at least get fuel gas or oil with high heat capacity. It also discharges low waste gas and low toxic gas including SOx, NOx and HCl heavy metals. However, pyrolyzed oil includes enough excess unsaturated hydrocarbons to form tar, which can cause the nozzle of engines to plug when pyrolyzed oil is used as fuel. Activated carbon was proven to have prominent adsorption capability among the other adsorbents that were mainly composed of carbon. This study examined the possibility of application in activated charcoal of its solid formation by analysing the feature of pyrolysis which is one of the chemical recycling methods and getting chemical analysis of the product and activated energy. Analyze the element of the oil produced by pyrolysis using GC-MS. The experiment of tar adsorption using fly-ash showed that fly-ash improved the optical intensity of pyrolyzed oil and decreased oxygen compounds in the pyrolyzed oil.

• Journal of the Korean Society for Marine Environment & Energy
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• v.5 no.2
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• pp.50-61
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• 2002

This paper - following 'Functional requirement of marine waste cleaning ships and organization of the fleets'[1] - describes on the preliminary conceptual design procedure for the multi-purpose marine waste cleaning system for shallow waters. The working area of this system is Yellow Sea and part of South Sea of South Korea. As the first step, we determined the functional requirements including the daily target of waste collecting. Then, the preliminary conceptual design and general arrangements were carried out. In order to evaluate the safety and efficiency of this designed system, the stability check and the computer graphic simulation were carried out. Finally, the sea trial performance test of integrated systems in Yeosoo ports was performed and the designed system was shown its validity and effectiveness.

• Journal of the Korean Society for Marine Environment & Energy
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• v.7 no.4
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• pp.180-184
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• 2004

The purpose of this study is the improvement of a hook for the collection of marine wastes on the seabed, which is connected to the spring device. The performance of the modified hook was tested on the seabed around Wando island. The collection efficiency of the hook was improved especially in the rocky area on the seabed. A experiment in the study area is verified with seafloor images displayed by Side Scan Sonar. The modified hook can be used for the collection of marine wastes with the its less frequent loss in the sea.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.17 no.4
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• pp.115-121
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• 2017

A wireless sensor network is a network in which nodes equipped with sensors capable of collecting data from the real world are configured wirelessly. Because the sensor nodes are configured wirelessly, they have limited power such as batteries. If the battery of the sensor node is exhausted, the node is no longer usable. If more than a certain number of nodes die, the network will not function. There are many wireless sensor network protocols to improve energy efficiency, among which LEACH Protocol is a typical example. The LEACH protocol is a cluster-based protocol that divides sensor space into clusters and transmits and receives data between nodes. Therefore, depending on how the cluster is structured, the shape of the energy cow may decrease or increase. We compare the network lifetimes of the existing LEACH protocols and the three types of protocols that have been improved using fuzzy methods for cluster selection.

• Journal of environmental and Sanitary engineering
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• v.23 no.3
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• pp.9-22
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• 2008

This study was conducted to develop a system that processes harmful gases and dust, which being generated in the production of micro-inorganic fabric. This can be obtained by melt spinning raw materials such as agalmatolite, fluorspar, limestone, silica under high temperature at $1500-1600^{\circ}C$ in a glass recuperator using a dry method by Cyclone Reactor or Envelope Type (ET) type Bag Filter. If the number of the members of Korea Glass Industry Association reaches up to 45, the damage of the harmful gas being generated in recuperator should not be small. In addition, research of existing facilities showed the most of harmful gas treatment facilities which adopt wet treatment or semi-dry treatment process. This was caused the problems for wastewater and the second pollutive materials. Moreover, in the dust collecting facility behind recuperator, it is also problematic that electric dust collector requires enormous initial investment. We have researched various methods to show both economic and efficient new processes for the preventive facilities of recuperator. As the result of the experiments, the removal efficiencies of HF and SOx were 99% and 87%, respectively. Although it was insignificant reaction, a pretty much interesting result that NOx showed an absorption reaction with $Ca(OH)_2$(removal efficiency was more than 25%) was obtained.

• Journal of the Korea Society for Simulation
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• v.29 no.3
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• pp.73-82
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• 2020

In the fourth industrial revolution, wireless sensor networks (WSNs) are an important element of collecting and analyzing data in a variety of environments without human intervention. This sensor network is greatly affected by topology and routing protocols. Routing protocols, which affect energy consumption, are executed after deploying sensor nodes. Once built, they are difficult to change. Before the WSN is deployed, a routing protocol is carefully selected in view of various environments and the performance of the protocol is evaluated. In this paper, we propose a model to simulate multiple routing protocols using a discrete event system specification (DEVS). The DEVS-based proposed model simulates various situations without changes and structures of the its model as algorithms of the routing protocols are implemented in its coordinators model. To verify normal behaviors of the proposed model, the number of report delivery and the energy consumption of the sensor network were compared using representative protocols LEACH and Dijkstra. As a result, it was confirmed that the proposed model executes normally in both routing protocols.

• The Journal of the Korea Contents Association
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• v.22 no.6
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• pp.557-566
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• 2022

The purpose of this study is to understand the correlation between Master Jin Bodhi and practicing Medicine Buddha, and to examine the concept and value of the method of asceticism related to practicing Medicine Buddha. Accordingly, as a result of collecting and analyzing a wide range of literature data on Master Jin Bodhi, Master Jin Bodhi was able to capture and present various historical sources of using various method of asceticism based on practicing Medicine Buddha. In addition, the concept and value of the method of asceticism about The Method of Great Illuminated Asceticism, Throwing Five Parts of the Body, and Energy Bagua were considered and presented as representative practices among the various practices taught to modern people in physical and mental weaknesses across the world. This study is of academic significance in that it clearly distinguishes the concepts and unique values of each of the The Method of Great Illuminated Asceticism, Throwing Five Parts of the Body, and Energy Bagua based on the results of the correlation between Master Jin Bodhi and practicing Medicine Buddha. Nevertheless, this study did not fully reveal the historical causality of the process of expanding Master Jin Bodhi's method of asceticism related to practicing Medicine Buddha, and has limitations in not considering the concept and value of the method of asceticism other than the The Method of Great Illuminated Asceticism, Throwing Five Parts of the Body, and Energy Bagua. Specific methods for further research were suggested.

• Journal of the Korean Association of Geographic Information Studies
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• v.10 no.1
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• pp.60-72
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• 2007

In general, the importance of geological information is emphasized not only for national SOC construction, underground space development and energy resources development but also in areas related to environmental disasters such as mine damage, ground subsidence and landslides. Although geological information is highly useful in developing industrial raw materials, national land management and people's welfare, there is no unified governmental institution in charge of collecting and managing geological information in the national level. For this, this paper study: first, to analyze geological demand for common experts; second, to analyze geological demand for public institution; and third, to set priority for geological informatization. In the result of surveying demand for geological information, we need to improve laws and systems for collecting and reporting geology-related materials, making thematic maps, and maintaining and managing geological information we need to establish national strategies and build an integrated system for interoperability of databases and systems. Accordingly, we will guideline on future direction of strategies for the national integration of geological information management system.