• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.19 no.8
• /
• pp.552-561
• /
• 2018

Biomass, a carbon-neutral resource, is an alternative energy source for exhaustion of fossil fuel and environmental problems. Most of energy production systems using biomass operate with a thermal chemical conversion method. Amongst them, gasification generates syngas and applies to boilers or engines for the production of heat and electricity. However, Tar could be formed during the production of syngas and it is condensed at low temperature which may cause to clog the pipelines and combustion chamber, ultimately resulting in decrease of process efficiency. Thus this work utilized water and oily materials such as soybean oil, waste cooking oil and mineral oil for scrubbing liquid. The removal efficiency of Tar appeared 97%, 70%, 63% and 30% for soybean oil, waste cooking oil, mineral oil and water respectively.

• The Journal of the Korea Contents Association
• /
• v.7 no.8
• /
• pp.134-141
• /
• 2007

In 3D animation rendering process, Although we can render the output as a movie file format, most productions use image sequences in their rendering pipelines. This Image Sequence rendering process is extremely important step in final compositing in movie industries. Although there are various type of making image rendering processes, TGA format Is one of most widely used bitmap file formats using in industries. People may ask TGA format is most suitable for in any case. As we know 3D softwares have their own image formats. so we need to testify on this. In this paper, we are going to focus on Alias' 3D package software called MAYA which we will analyze of compressing image sequence, Image quality, supporting Alpha channels in compositing, and Z-depth information. The purpose of this paper is providing to 3D Pipeline as a guideline about effective image sequence format.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.24 no.4
• /
• pp.50-56
• /
• 2010

Supervisory Control and Data Acquisition Systems (SCADAs) is real-time monitor and control systems. SCADA systems are used to monitor or control chemical and transportation processes, in municipal water supply systems, electric power generation, transmission and distribution, gas and oil pipelines, and other distributed processes. SCADA refers to a large-scale distributed system. The supervisory control system is placed on top of a real time control system to control external processes. Emerging security technologies and security devices are decreasing the vulnerability of the power system against cyber threats. Dealing with these threats and analyzing vulnerabilities is an important task for equipment such as RTU, IED and FEP. To reduce such risks, we develop such a SCADA testbed. This paper presents the development of a testbed designed to assess the vulnerabilities SCADA networks(including serial communication).

• Journal of Navigation and Port Research
• /
• v.30 no.3 s.109
• /
• pp.189-195
• /
• 2006

Sea operation monitoring system is a system for the automatic ship operation that is used on the variety sea operations such as laying optical cables on the sea between the countries, laying cables on the seabed for a remote island, laying pipelines for the natural gas, and so forth. This system processes data which obtained through setting up environment and input from several sensors, and display GPS information with ENC data. And this system processes not only data of route file about sea operation, but also realtime information from PDA of client wirelessly connected with AP on wireless LAN. In addition, this system can improve efficiency of the operation as a result of enabling free movement within valid range. This paper design and implementation monitoring system from above appropriate to the embedded system, and improve competitive power of ship through prevention of a ship accident, to keep minimizing operation loads and support both the automatic ship operation and the safety voyage.

• Journal of Korean Society on Water Environment
• /
• v.24 no.3
• /
• pp.273-279
• /
• 2008

Space separation method that use independent reactor for nitrification and other reactor for denitrification has been commonly used for biological nitrogen removal process like $A^2O$ process. However, this method needs large space and complicate pipelines and time separation method such as SBR process have a difficulty in continuous treatment. Thus biological nitrogen removal process which is capable of continuous treatment, easy opeation and space saving is urgently required. In this research, submerged moving media was used for a biofilm process and suspended sludge was used for biological nitrogen removal at the same time. In particular DO environment by controlling air flow rate was investigated for simultaneous nitrification/denitrification. Total nitrogen removal in aeration rate more than $67L/min{\cdot}m^3$ showed 51~53% and rose to 65%, 70% and 78% in $50L/min{\cdot}m^3$, $58L/min{\cdot}m^3$ and $25L/min{\cdot}m^3$ respectively. Total phosphorus removal was very low about 10~20% more than $67L/min{\cdot}m^3$ aeration rates. But total phosphorus removal roses when reduces aeration rate by $58L/min{\cdot}m^3$ low and it showed total phosphorus removal of 72% in aeration rate $25L/min{\cdot}m^3$.

• Plant Journal
• /
• v.10 no.4
• /
• pp.35-41
• /
• 2014

The height and capacity of the thermal storage tank can be decided by the altitude and heat load of the heat supply area. Evaporation in heat pipe can be prevented by pressurizing it with the hydraulic head of the thermal storage tank. In addition, it absorbs the expanded volume from the temperature changes and supplies water to the pipelines in case of the shortage of water. One of the most important roles of the thermal storage tank is a stable heat supply facility. It can control the heat demand by accumulating the surplus heat and supplying in changing heat demand time. The purpose of this thesis is to be helpful for the operation and maintenance of the thermal storage tanks. The study has been carried out for 18 thermal storage tanks, which have been used polyurethane foam as insulation, among 27 tanks in district heating plants. The characteristics of the insulation materials, the reasons for the damages of the insulation and how impact the insulation damages to the corrosion of the thermal storage tank have been studied.

• Journal of Ocean Engineering and Technology
• /
• v.19 no.4 s.65
• /
• pp.35-41
• /
• 2005

There has been increasing offshore oil exploration, drilling, and production activities, as well as a huge amount of petroleum being transported by tankers and pipelines through the ocean and costal environment. Assessment must be made of the potential risk of damage resulting from the exploration, development and transportation activities. This is achieved through predictive impact evaluations of the fate of hypothetical or real oil spills. VVhen an oil spill occurs, planning and execution of cleanup measures also require the capability to forecast the short-term and long-term behavior of the spilled oil. A great amount of effort has been spent by government agencies, oil industries, and researchers over the past decade to develop more realistic models for oil spills. Numerous oil spill models have been developed and applied, most of which attempt to predict the oil spill fate and behavior. For an actual contingency planning, the oil fate and behavior model should be combined with an oil spill incident model, an environmental impact and risk model and a contingency planning model. The purpose of this review study is to give an overview of existing oil spill models that deal with the physical, chemical, biological, and socia-economical aspects of the incident, fate, and environmental impact of oil spills. After reviewing the existing models, future research needs are suggested. In the study, available oil spill models are separated into oil spill incident, oil spill fate and behavior, environmental impact and risk, and contingency planning models. The processes of the oil spill fate and behavior are reviewed in detail and the characteristics of existing oil spill fate and behavior models are examined and classified so that an ideal model may be identified. Finally, future research needs are discussed.

• International Journal of Fluid Machinery and Systems
• /
• v.9 no.3
• /
• pp.245-255
• /
• 2016

The alternating flow hydraulics (AFH) had demonstrated the unique features in the past. One of the most well-known inventions was the hydraulic machine-gun synchronizer, which had become the standard equipment of airplane during World War I. The studies on the AFH between 1960 and 1980 had trigged many researchers' interests and reached the summit. The disadvantages of the AFH like low efficiency and cooling difficulty had prevented the further development. Few people are engaged in studying the AFH at present. However, the unique characteristics of the AFH inspire the researchers to continuously explore the new special suitable applications. The overviews of the AFH and the new potential application in the geotechnical testing field have been discussed in this paper. First, the research results of the AFH in the past have been summarized. Then, the classifications of the AFH have been introduced in detail according to the working principle, the number of hydraulic transmission pipelines and the mode of input energy. The advantages and the disadvantages of the AFH have been discussed. A novel potential suitable application in the soil test field has been presented at last. The detailed designing ideas of a new dynamic trixial instrument have been given, which will be a more innovational and energy-saving plan according to the current studies. A series of simulation experiments have been done. The simulation results show that the proposed scheme for the new dynamic trixial instrument is feasible. The paper work will also give some inspirations in the reciprocating motion control system.

• Strategy21
• /
• s.41
• /
• pp.153-173
• /
• 2017

On 15 December 2015, China seized an underwater drone belonging to the U.S. in the South China Sea. The underwater drone was then about to be retrieved by the Bowditch, a U.S. naval ship.Although China returned the underwater drone to the U.S. on 20 December 2016, the incident resulted in the considerable controversy involving the use of underwater drones. The reason for this is that the seizure of the underwater drone happened in the exclusive economic zone (hereafter referred to as "EEZ") of the Philippines. Part XIII of the United Nations Convention on the Law of the Sea (hereafter referred to as "UNCLOS") governs the matters of marine scientific research (hereafter referred to as "MSR"). If a State intends to use an underwater drone in the EEZ of another coastal State for the purpose of MSR, the former has to obtain the consent of the latter in accordance with relevant provisions included in Part XIII of the UNCLOS. However, it is not obvious whether the consent of a coastal State should be required to launch an underwater drone in the EEZ of the State for the purpose of hydrographic surveying or military surveying. Maritime powers such as the U.S. regard hydrographic surveying or military surveying as part of "other internationally lawful uses of the sea related to these freedoms, such as those associated with the operation of ships, aircraft and submarine cables and pipelines" found in Article 58(1) of the UNCLOS, or part of the freedom of the high seas. This interpretation is not incompatible with the implications that the UNCLOS has. Nevertheless, Korea cannot accept this kind of interpretation that is supported by maritime powers. The freedom of hydrographic surveying or military surveying could imply that the EEZ of Korea would be full of underwater drones launched by China, Japan or even Russia. Hence, Korea should claim that the data collected for the purpose of MSR cannot be distinguished from that collected for the purpose of hydrographic surveying or military surveying. This means that hydrographic surveying or military surveying without the consent of a coastal State in the EEZ of the State should not be permitted.

• Journal of the Korean Geotechnical Society
• /
• v.29 no.12
• /
• pp.69-75
• /
• 2013

Pipeline is very important infrastructure which is directly related to our daily life. Nevertheless, it is not considered significantly unless it breaks. As most pipelines are buried at a certain depth from the surface of road pavement in urban areas, they are subjected to traffic load. This paper presents the performance of buried concrete pipe under heavy traffic load. Hence, one of the major factors affecting their performance is burial depth. To consider this factor, the ratio of burial depth (H) to diameter of pipe (D) was defined as a key variable. The integrity of buried concrete pipe was investigated with two cases of ratio of burial depth to pipe diameter (H/D=2 and H/D=4). The results provide the limit burial depth to ensure the soundness of buried concrete pipe subjected to heavy traffic load, and more economical design is anticipated with the results.