• Hwankyungkyoyuk
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• v.2 no.1
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• pp.92-99
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• 1991

According to our secondary school curriculum for natural science and technical circles, there be used 353 of chemical reagents including 24 kinds of harmful and toxicant components. At present, most school are discharging their school laboratory waste water without any chemical and physical treatments. So as to solve the environmental problem for water pollution, this study tried to research a kind of adsorbant utilizing saw dust, wasted wood sources and designed the simple processing system using the adsorbent. This adsorbent was made by extracting lignin substances from raw saw dust under the solution of 0.5N-NaOH at the temperature of $100^{\circ}C$. Their metal removed rates was measured not only by processing of column and vessel. but also by comparing the standard solution and real waste water. The results were proved as more than 90(%) of the adsorptive efficiency on the average from Pb, Cd, Cu except Cr(VI)in case of the school experimental waste water soaked in vessels a long with 4g of the adsorbent for 24 hours. The new processing system enables to remove most harmful and toxicant metals by filtering, sedimenting and adsorbing at the low cost.

• IEIE Transactions on Smart Processing and Computing
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• v.4 no.2
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• pp.78-82
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• 2015

General-purpose graphics processing units (GPGPUs) provide tremendous computational and processing power. Despite the latency hiding mechanism, a GPU architecture requires high memory bandwidth and lower latency between computational units and the memory system. For this reason, the current GPU architecture has private L1 caches in each core and a shared L2 cache to increase performance by reducing memory latency. But in some cases, this CPU-like cache design is not suitable for GPGPUs. In this paper, we analyze detailed cache performance related to GPGPU application characteristics, and suggest technical alternatives for the GPGPU architecture as future work.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.66 no.6
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• pp.988-994
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• 2017

The risk of facilities in catenary is increasing because the railway section extension and high-speed train service. And visual check of workforce is not enough time to maintain the extensive railway facilities. Accordingly, The technical development trend of maintenance of railway facilities can be seen by automation and application of IT technology, especially the mechanization work and the information technology are spreading in the maintenance work of the train line solved by manpower. In this paper, we describe the method by obtaining the cantilever image using acquisition device and pole inspection system in high speed vehicle, to check the variation of the cantilever component using image processing.

• The Journal of the Korea Contents Association
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• v.12 no.8
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• pp.13-19
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• 2012

This paper introduces a test-bed toolkit for evaluating and enhancing text analysis engines which extract technological knowledge from articles, patents, reports and so forth. The toolkit consists of two test-beds for technical entity recognition and relation extraction engines, which are capable of identifying technical entities and predicting semantic relation types between the entities. With using the introduced toolkits, users and developers can efficiently perform the execution monitoring and error analysis of the technical text analysis engines.

• Laser Solutions
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• v.6 no.2
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• pp.1-7
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• 2003

Defocused CO$_2$ laser beam irradiation strengthening of 60kgf/$\textrm{mm}^2$ grade steel sheet was investigated to obtain the tensile strength similar to that of fully penetrated one by the focused beam. The melted line width by the defocused beam was 3∼4 times larger compared to that of the focused beam. However, the increase of tensile strength with 1 line irradiation by the defocused beam was similar to that of 2~3 lines by the focused beam. The increase(37.6%) of bending strength with 1 line by the defocused beam was higher than the increase(12.9%) of tensile strength. Also, the effect of cooling gas to strengthening was observed.

• Proceedings of the International Microelectronics And Packaging Society Conference
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• 2000.04a
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• pp.29-33
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• 2000

MEMS, Micro Electro-Mechanical Systems, present one of the greatest advanced packaging challenges of the next decade. Historically hybrid technology, generally thick film, provided sensors and actuators while integrated circuit technologies provided the microelectronics for interpretation and control of the sensor input and actuator output. Brought together in MEMS these technical fields create new opportunities for miniaturization and performance. Integrated circuit processing technologies combined with hybrid design systems yield innovative sensors and actuators for a variety of applications from single crystal silicon wafers. MEMS packages, far more simple in principle than today's electronic packages, provide only physical protection to the devices they house. However, they cannot interfere with the function of the devices and often must actually facilitate the performance of the device. For example, a pressure transducer may need to be open to atmospheric pressure on one side of the detector yet protected from contamination and blockage. Similarly, an optical device requires protection from contamination without optical attenuation or distortion being introduced. Despite impediments such as package standardization and complexity, MEMS markets expect to double by 2003 to more than ＄9 billion, largely driven by micro-fluidic applications in the medical arena. Like the semiconductor industry before it. MEMS present many diverse demands on the advanced packaging engineering community. With focused effort, particularly on standards and packaging process efficiency. MEMS may offer the greatest opportunity for technical advancement as well as profitability in advanced packaging in the first decade of the 21st century! This paper explores MEMS packaging opportunities and reviews specific technical challenges to be met.

• Advances in concrete construction
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• v.1 no.3
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• pp.227-237
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• 2013

Modal testing, widely accepted and applied method for determining the dynamic characteristics of structures for operational conditions, uses known or unknown vibrations in structures. The method's common applications includes estimation of dynamic characteristics and also damage detection and monitoring of structural performance. In this study, the structural identification of concrete arch dams is determined using ambient vibration tests which is one of the modal testing methods. For the purpose, several ambient vibration tests are conducted to an arch dam. Sensitive accelerometers were placed on the different points of the crest and a gallery of the dam, and signals are collected for the process. Enhanced Frequency Domain Decomposition technique is used for the extraction of natural frequencies, mode shapes and damping ratios. A total of eight natural frequencies are attained by experimentally for each test setup, which ranges between 0-12 Hz. The results obtained from each ambient vibration tests are presented and compared with each other in detail. There is a good agreement between the results for all measurements. However, the theoretical fundamental frequency of Berke Arch Dam is a little different from the experimental.

• Journal of Internet Computing and Services
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• v.10 no.3
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• pp.95-101
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• 2009

As RFID technology has been developed rapidly, its technical potential has it be widely used in many industrial fields. Particularly, in the physical distribution industry, the introduction of RFID has enormously contributed to effectively monitoring locations and information of products in real-time. Also, a significant decline in tag prices and RFID related technical competitiveness enabled each tag to be managed much more minutely by attaching it to an item, not a pallet nor a container. However, if a very large volume of tag data are continuously flowed into a RFID middleware with limited hardware resources, its entire data processing time may become considerably longer. Therefore, specific technologies are in great demand to handle and further to reduce the load of the middleware. In this paper, we proposed a mobile agent-based software module to efficiently reduce the load of the middleware by pre-processing a lot of tag data while items are in transit. Simulation results show that using the proposed software module considerably enhances the speed of processing tag data than otherwise. This behavior increases the tag recognition rate in a certain time limit and improves reliability of RFID middlewares.

• Polymer(Korea)
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• v.31 no.1
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• pp.31-36
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• 2007

It has been reported that the surface properties of the plasma treated material were changed while maintaining its bulk properties. In this study, surface modification of nylon fiber by plasma treatment was tried to attain high water-repellency Nylon fiber was treated with RF plasma under a vacuum system using various parameters such as gas specious, processing time and processing power. Morphological changes by low pressure plasma treatment were observed using scanning electron microscopy (SEM) and atomic force microscopy (AFM). Moreover, the mechanical and inherent properties were analyzed by tensile strength, differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The high water-repellency property of nylon fiber was evaluated by a water-drop standard test under various conditions in terms of aging effect. The results showed that the water-repellency of plasma-surface-treated nylon fiber was greatly improved compared to untreated nylon fiber.

• Resources Recycling
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• v.22 no.4
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• pp.70-80
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• 2013

Waste refrigerator is the most large amount of item being recycled and the recycling process is the most complicated in WEEE (Waste Electrical and Electronic Equipment) because refrigerator is biggest product and consists of various parts and materials such as ferrous, non-ferrous, and plastics. Recently, recycling process of waste refrigerator has been being more complex since large capacity 2 door refrigerators and standing Kimchi refrigerators with various material are distributed on custom market. In addition, recycling of valuable resource from waste refrigerator is mandatory by WEEEs recycling legislation; therefore, high efficiency recycling enough for economic and environment-friendly recovery of valuable resource through present technical situation analysis and comparison of recycling technologies of waste refrigerator with advanced country.