• Transactions of the Korean Society of Machine Tool Engineers
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• v.17 no.6
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• pp.118-123
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• 2008

Weakness process can be called ferrule array and epoxy filling process at connector manufacturing process, and a lot of problems happen as think as general manufacturing process at early investment. Wished to improve this and working environment mend of worker on childhood(planning phase) and problem that is happened at done ferrule array and epoxy injection by emphasis target. By ferrule sorting and Improvement of epoxy filling process, bring authoritativeness elevation of product by fraction defective decrease of product by sized work along with productivity elevation. On the other hand, working jigs are various in characteristics of optical connector manufacturing line. There have been lots of restriction in practice because the applicability of this system is only for single type model though the network should be smooth between lines. Thus, it is not only needed the recognition of necessity in industrial line but also the development of automation system arraying ferrule and filling epoxy in the manufacturing process. It is found that the present system development enhances productivity fairly and prevents industrial disaster in the optical connector manufacturing system.

• International Journal of Contents
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• v.7 no.2
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• pp.42-48
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• 2011

The aim of this study is to investigate college students' opinion on participation in media education. The research question is as follows: first, what is the college students' perceptions who participated in media education? Second, what are the differences among the perceptions of college students who participated in media education? To answer these research questions, we used Q-methodology, which is more useful in organizing subjectivity types and opinions of students, both in explaining and sorting of data by characteristic and personal opinion. As a result, two types were found; type 1 is the active participation type that focuses on the active participation in media education as a productive tool and teaching method, as well as diminishing the current controls and restrictions on its use in education. On the other hand, type 2 is the growing adaptive type and is positive for the future development of media education in a transitional role, while they think that current media education for college students is not qualitative yet, a productive tool and the quality of the information message is lacking, and so on.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.13 no.3
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• pp.1238-1259
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• 2019

Saving energy is a big challenge for Wireless Sensor Networks (WSNs), which becomes even more critical in large-scale WSNs. Most energy waste is communication related, such as collision, overhearing and idle listening, so the schedule-based access which can avoid these wastes is preferred for WSNs. On the other hand, clustering technique is considered as the most promising solution for topology management in WSNs. Hence, providing interference-free clustering is vital for WSNs, especially for large-scale WSNs. However, schedule management in cluster-based networks is never a trivial work, since it requires inter-cluster cooperation. In this paper, we propose a clustering method, called Interference-Free Clustering Protocol (IFCP), to partition a WSN into interference-free clusters, making timeslot management much easier to achieve. Moreover, we model the clustering problem as a multi-objective optimization issue and use non-dominated sorting genetic algorithm II to solve it. Our proposal is finally compared with two adaptive clustering methods, HEED-CSMA and HEED-BMA, demonstrating that it achieves the good performance in terms of delay, packet delivery ratio, and energy consumption.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2022.10a
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• pp.172-174
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• 2022

Logistics processing companies in Korea are mostly handling various types of products in and out. In order to process various types of products, the sorting business is performed by hand. In this paper, we propose a real-time QR code detection method using a vision sensor to achieve high efficiency with a small amount of manpower. The limiting system uses a vision sensor to process QR code recognition of logistics in real time. The proposed system can quickly identify a large number of QR codes through multiple recognition rather than QR code recognition, which is a single part of logistics. In the study, the system was actually implemented and verified, and multiple QR recognition was confirmed in the image through the vision center.

• Ecology and Resilient Infrastructure
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• v.2 no.2
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• pp.118-127
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• 2015

Because streams have a great diversity of morphological features according to their reaches, it is necessary to classify the types of streams in order to assess their characteristics of channel. In addition, a quantitative assessment system for channel characteristics should be reflected in the stream type properties. Therefore, this study compares two stream classification system (Rosgen's and Yamamoto's) to review their applicability on Korean streams, and the two classification systems were applied on the Nam River. In order for the mean bed slope and the longitudinal connectivity of the provincial and national streams to be reflected in the assessment system of channel characteristics, the Yamamoto system is considered highly adaptable in the stream geomorphology side. In addition, it has been found the Rosgen system has a low correlation of bed slope compared to the Yamamoto system in the view of bed materials. On the other hand, the Yamamoto system was found to be capable of reflecting sediment sorting (hydraulic sorting) of the bed slope. According to the results obtained at the Nam River, the Rosgen system could not classify a type of stream by relationship between bed material and bed slope, but the Yamamoto system can verify the correlation of stream type. However, further review is needed with respect to the applicability of natural rivers. Three types of stream that can be applied to the assessment system of channel characteristics were proposed.

• The Korean Journal of Quaternary Research
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• v.7 no.1
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• pp.27-39
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• 1993

The shingle beach as a typical pocket beach located in Jeongdo-ri, Wando, Cheolanam-do, Korea has been investigated in terms of textural characteristics, mainly gravel shape and roundness. In the Jeongdo-ri gravel beach, changes of beach profile after storm weather and textural parameters of gravels were observed and measured from May 1992 to March 1993. Beach profile is divided into two different Fair-weather zone and Storm-weather zone influenced by dynamic condition of wave energy. The former is affected by wave and tide under fair-weather condition, the latter seems to be formed under storm-weather condition. Each zone comprises a series of beach faces and berms formed by continuous sedimentary processes of swash, overwash and backwash. Storm-weather zone is subdivided into three groups having a pair of beach face and berm respectively. Mean sizes of berm gravel(45.5 mm -123.6 mm) are coarser than gravels of beach face (36.8 mm - 78.3 mm) in fair-weather zone. On the other hand, in storm-weather zone, gravels of berms (33.1 mm -82.5 mm) are finer than those of beachfaces (46.2 mm - 105.2 mm). The proportion of disc shaped gravels of berm (50.0% - 58.5 %) is higher than that of beachface (45.9 % - 51.3 %) in each subzone except C-group of storm-weather zone. And the proportion of the equant shaped gravel increases about up to 10% seaward. Therefore, shore-normal distribution of gravels seems to be affected by shape and size sorting effects. Shore-parallel distribution pattern of gravel shape is more distinctive than size distribution patterns. That is, disc and blade shaped particles decrease up to 20% and 13% respectively, and equants increase up to 34% to the westward. Gravels plotted on Sneed and Folk's triangular diagram are more compacted and elongated with decreasing size. Therefore primary gravels are shaped by characteristics of country rock e.g. cleavage, joint etc., and secondary are affected by sorting and size-controlled process evolution by wave action.

• Journal of the Korea Computer Graphics Society
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• v.23 no.3
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• pp.87-94
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• 2017

Due to improvements in the capabilities of commercial game engines, there are increasing instances of applying game engines to scientific visualization applications. This study describes a case of creating a virtual reality application that visualizes medical volume data based on the Unity3D game engine. When using a game engine, there is an advantage that various functions required for an application are basically provided, such as depth sorting of translucent objects or virtual reality hardware support. On the other hand, there is a restriction that the structure of the application program should be modified to suit the characteristics of the game engine. This paper describes a method for visualizing medical volume data using the structure of a game engine. As a result, we were able to create a virtual reality scene that consisted of surface data and medical volume data fragments together. And we confirmed the possibility of game engine as a future medical simulation production tool.

• Korean Journal of Environmental Biology
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• v.27 no.2
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• pp.135-139
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• 2009

The abundance of earthworm in the agroecosystem of Sunyu Island was estimated on the basis of 1,025 individuals collected in August and October, 2007. Material were collected from litter layers and soils by hand sorting and digging. They encompassed 12 species, 4 genera, and 3 families. Species composition and abundance were as follows: Amynthas heteropodus 29.7%, Aporrectodea tuberculata 22.6%, Aporrectodea caliginosa 19.5%, Drawida japonica 11.3%, Amynthasagrestis 5.0%, Amynthas hupeiensis 3.6%, Aporrectodea sp. 3.5%, Amynthas corticis 2.0%, Bimastos parvus 1.6%, Amynthas koreanus 0.8%, Amynthas hilgendorfi 0.2%, and Amynthas sp. 0.2%. Of 537 individuals, A. heteropodus, and A. tuberculata were the most numerous members with abundance of 52.4%. The clitellate vs. aclitellate ratio of the earthworm was approximately 1:1.1.

• Economic and Environmental Geology
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• v.7 no.3
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• pp.87-100
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• 1974

This paper deals with grain size analysis, heavy mineral analysis and trace element analysis of the recent sediments of Han River basin between Cheongpyong, Gyeonggi province and Seoul. For each location the samples are taken at river shoreline, river berm and river dune. The size analysis discloses that the mean values range from $-1.37{\phi}$ to $-1.60{\phi}$, sorting values range from 0.25 to 1.84, skewness values range from -0.44 to 0.51 and kurtosis values range from -0.1 to 1.75. Based on the textural parameters, the dune sand can be distinguished from the shoreline-berm sand. The content of heavy minerals of each sample ranges from 0.04 to 4.7%. The principal heavy minerals are ilmenite, magnetite, leucoxene, garnet, amphibole, pyroxene, kyanite, zircon, monazite, tourmaline, epidote, limonite, and minor minerals are apatite, sillimanite, andalusite and olivine. In general, dune sand samples contain more heavy minerals than the samples of shoreline or berm sand. This suggests that the heavy mineral concentration is affected by wind action more than by any other causes. The content of ilmenite and leucoxene decreases, whereas the content of zircon and epidote increases as it approaches the downstream region. The differences result from the variance of geological occurrences. The emission spectrochemical analysis and colorimetry analysis revealed that the content of Ni and V in the heavy minerals of the study area are higher than those of other stream sediments in Korea. On the other hand the content of Cu, Ph, Zn, Mo, W, P, Mn, Cr, Ag and Sn are lower in the study area. It has been observed also that the contents of all the elements except for Bi are higher in this area than the samples of marine sediments of Yellow Sea.

• Korean Journal of Environmental Biology
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• v.25 no.2
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• pp.88-93
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• 2007

The abundance of earthworm in the agro-ecosystem was assessed on the basis of 1,846 individuals collected from May to October 2006. Material was found from litter layers in soils by hand sorting and digging. They encompassed 3 families, 5 genera, and 15 species. Species composition and abundance were as follows: Amynthas agrestis 20.9%, Amynthas koreanus 20.3%, Amynthas heteropodus 15.4%, Amynthas sp. 8.7%, Drawida japonica 8.0%, Eisenia fetida 7.2%, Amynthas hilgendorfi 7.0%, Bimastos parvus 3.2%, Amynthas hupeiensis 2.5%, Aporrectodea caliginosa 1.8%, Amynthas corticis 1.8%, Aporrectodea tuberculata 1.3%, Eisenia andrei 1.2%, Amynthas sp. 20.4%, and Amynthas sp. 10.3%. Of 1,046 individuals, the A. agrestis, A. koreanus, and A. heteropodus were the most numerous members with abundance of 56.7%. Disc-shaped male pore region is useful for classification of Amynthas, and in the survey, we collected two new species with male discs from lettuce cultivated region, Amynthas sp. 1 Amynthas sp. 2. The clitellate vs. aclitellate ratio of the earthworm was approximately 1.25:1.0.