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A Study on the Emission Characteristics of Mercury in Municipal and Industrial Waste Incinerators (폐기물소각시설의 수은배출특성 연구)

  • Seok Kwangseol;Hong Jihyung;Lee Sukjo;Lee Daegyun;Kim Daigon;Park Jihyun
    • Journal of Korean Society for Atmospheric Environment
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    • v.20 no.2
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    • pp.205-213
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    • 2004
  • The emission characteristics of mercury in waste incinerators were investigated to get basic data for the policy development on the emission reduction of mercury (Hg). For the study several important factors were analysed from 4 incinerators such as mercury concentration, emission factors and removal rate for control devices. The results are listed below. Mercury concentrations in the flue gas were 0.39~5.96 $\mu\textrm{g}$/S㎥ in MWI and 2.5~8.8 $\mu\textrm{g}$/S㎥ in IWI. The distributions of gaseous and particulate mercury in flue gas were above 99% and below 1 %, respectively. Therefore, in order to remove mercury effectively, it is important to control the gaseous mercury. Mercury concentrations in fly ash collected from control device were found as 16.2~35.6 mg/kg- ash in FF of MWI. Also mercury concentrations at the front and back point of control device of MWI were 33.45~62.65 $\mu\textrm{g}$/S㎥ and 0.88~3.49 $\mu\textrm{g}$/S㎥, respectively. Emission factors were estimated as 3.67~11.67 mg/ton in FF, 2.6~24.5 mg/ton in MWI with SNCR, SDR and FF, 54.9~192.7 mg/ton in IWI with Cyclone and FF. Emissions from Municipal Waste Incinerator were found both in minimum and maximum ranges. Annual mercury emissions emitted from MWI was estimated as 20.0 kg (6.0~33.9 kg).

Applications of Artificial Neural Networks for Using High Performance Concrete (고성능 콘크리트의 활용을 위한 신경망의 적용)

  • Yang, Seung-Il;Yoon, Young-Soo;Lee, Seung-Hoon;Kim, Gyu-Dong
    • Journal of the Korean Society of Hazard Mitigation
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    • v.3 no.4 s.11
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    • pp.119-129
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    • 2003
  • Concrete and steel are essential structural materials in the construction. But, concrete, different from steel, consists of many materials and is affected by many factors such as properties of materials, site environmental situations, and skill of constructors. Concrete have two kinds of properties, immediately knowing properties such as slump, air contents and time dependent one like strength. Therefore, concrete mixes depend on experiences of experts. However, at point of time using High Performance Concrete, new method is wanted because of more ingredients like mineral and chemical admixtures and lack of data. Artificial Neural Networks(ANN) are a mimic models of human brain to solve a complex nonlinear problem. They are powerful pattern recognizers and classifiers, also their computing abilities have been proven in the fields of prediction, estimation and pattern recognition. Here, among them, the back propagation network and radial basis function network ate used. Compositions of high-performance concrete mixes are eight components(water, cement, fine aggregate, coarse aggregate, fly ash, silica fume, superplasticizer and air-entrainer). Compressive strength, slump, and air contents are measured. The results show that neural networks are proper tools to minimize the uncertainties of the design of concrete mixtures.

A Study on the Reflection of Digilog in Contemporary Fashion (현대패션에 나타난 디지로그(Digilog)에 관한 연구)

  • Kim, Sang-Ja;Park, Myung-Hee
    • Journal of the Korean Society of Costume
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    • v.61 no.3
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    • pp.139-152
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    • 2011
  • This research explores the idea of digilog for fashion; it would help to conclude the uncertain mixed-phenomena and words as a neologism and find a fundamental concept that would be a reference for a lot of uncertain new words that have been occurring even this year. Furthermore, this research is aimed at analyzing how digilog has been reflected on the contemporary fashion and directing the ways towards the future of fashion. The digilog fashion design is the expression of a combination of opposite extremes, that is to say the combination of a paradoxical mix and directly-opposed elements. The outward expression of fashion design with digilog can be classified into several ways. First of all, it tends to use the elements of paradoxical expression; for example, applying high-technology to express a primitive and natural material. The analog expresses unprocessed. Secondly, using high-tech machine to express the texture of handicraft or rough embroidery. Lastly, digital printing(DTP) is applied to enlarge the several or the whole parts of a natural object or sensitivity. As a result of the analysis, the inside view of the contemporary fashion with digilog delineate followings; it is the attitude that claims to go back to the past and accepts the combination of nature and high-technology to get calmness in the rapidly changing modern world. And it is the will to fly from the utterly exhausted reality through the recurrence of the past when there used to be a lot of energies and used to live in affluence.

Characteristics of Basalt Materials Derived from Recycling Steel Industry Slags (철강산업 슬래그를 이용하여 제조한 바잘트 소재의 특성)

  • Jung, Woo-Gwang;Back, Gu-Seul;Yoon, Mi-Jung;Lee, Jee-Wook
    • Korean Journal of Materials Research
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    • v.27 no.5
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    • pp.281-288
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    • 2017
  • In this study, Fe-Ni slag, converter slag and dephosphorization slag generated from the steel industry, and fly ash or bottom ash from a power plant, were mixed at an appropriate mixing ratio and melted in a melting furnace in a mass-production process for glass ceramics. Then, glass-ceramic products, having a basalt composition with $SiO_2$, $Al_2O_3$, CaO, MgO, and $Fe_2O_3$ components, were fabricated through casting and heat treatment process. Comparison was made of the samples before and after the modification of the process conditions. Glass-ceramic samples before and after the process modification were similar in chemical composition, but $Al_2O_3$ and $Na_2O$ contents were slightly higher in the samples before the modification. Before and after the process modification, it was confirmed that the sample had a melting temperature below $1250^{\circ}C$, and that pyroxene and diopside are the primary phases of the product. The crystallization temperature in the sample after modification was found to be higher than that in the sample before modification. The activation energy for crystallization was evaluated and found to be 467 kJ/mol for the sample before the process modification, and 337 kJ/mol for the sample after the process modification. The degree of crystallinity was evaluated and found to be 82 % before the process change and 87 % after the process change. Mechanical properties such as compressive strength and bending strength were evaluated and found to be excellent for the sample after process modification. In conclusion, the samples after the process modification were evaluated and found to have superior characteristics compared to those before the modification.

The Ballast for Field Emission Lamp with CNT Emitter (CNT를 이용한 무수은 면광원 안정기 개발)

  • Park, Dong-Hyuck;Ha, Seok-Jin;Jung, Hye-Man;Kim, Jong-Hyun;Baek, Ju-Won;Yoo, Dong-Wook;Song, Eui-Ho
    • The Transactions of the Korean Institute of Power Electronics
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    • v.14 no.1
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    • pp.31-37
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    • 2009
  • Hybrid ballast for field emission lamp with CNT (carbon nano tube) emitter is proposed. Hybrid ballast consists of a high voltage dc part and hi-polar pulse generation part. Field emission lamp with CNT lamp is composed of three electrodes (anode, gate, and cathode). High voltage dc part is for anode and gate and hi-polar pulse generation part is for gate and cathode in CNT triode respectively. The experimental results demonstrate that the proposed topology is good for driving CNT lamp. To protect the lamp and ballast, OCP (Over Current Protection), OVP (Over Voltage Protection), and OTP (Over Temperature Protection) are added and the experimental results demonstrate that the proposed method is good for driving field emission lamp with CNT emitter.

Asia and Europe: So Distant So Close? The Case of Lipoptena fortisetosa in Italy

  • Andreani, Annalisa;Giangaspero, Annunziata;Marangi, Marianna;Barlaam, Alessandra;Ponzetta, Maria Paola;Roy, Lise;Belcari, Antonio;Sacchetti, Patrizia
    • Parasites, Hosts and Diseases
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    • v.58 no.6
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    • pp.661-668
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    • 2020
  • In Europe, 5 Lipoptena species have been recorded, including Lipoptena fortisetosa. This species, native to Asian countries, was described as a parasite of sika deer and its appearance in Europe dates back to more than 50 years ago. Lipoptena fortisetosa has been recently reported in Italy, sharing its hosts with Lipoptena cervi. A morpho-molecular approach was developed to determine the phylogenetic interrelationship of Italian and Asian CO1 haplotypes sequenced from Lipoptena fly individuals collected in Italy, and their DNA sequences were compared with conspecifics available in GenBank; morphological key-characters (terminalia) of L. fortisetosa were compared with the original description. Two haplotypes were recorded from Italy and assigned to L. cervi and L. fortisetosa, respectively. The latter was part of the monophyletic clade L. fortisetosa, along with 2 Central European and 2 Korean haplotypes (100% identical to one of the Korean haplotypes); moreover, Italian L. fortisetosa female terminalia were consistent with the original description of Asian individuals. Pending more in-depth investigations, this study provides a first answer to the hypothesis of the recent colonization of Italy by L. fortisetosa from Asia as we did not detect any obvious and stable morphological and molecular differences in specimens from the 2 geographical areas. The presence of the sika deer in Europe was retraced and the possible route traveled by the parasite from Asia and the eco-biological factors that may have enhanced its settlement are discussed.

UAM Parallel Corridor Collision Risk Analysis based on Collision Risk Model (충돌 위험 모델을 활용한 UAM 평행 항로 충돌 위험 분석)

  • Youn-sil Kim;Joong-won Bae
    • Journal of Advanced Navigation Technology
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    • v.27 no.5
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    • pp.561-567
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    • 2023
  • In this study, the collision risk of the UAM (Urban Air Mobility) corridor was analyzed using a collision risk model applied to the manned aircraft corridor. According to the K-UAM roadmap and operating concept, UAM is expected to fly on a designated route similar to existing manned aircraft operations and operate on two routes, traveling back and forth between the departure point and the destination point. Among domestic manned aircraft routes, the manned aircraft operation between Gimpo Airport and Jeju Airport is similar to this and takes the form of a parallel route with a lateral separation distance between the two routes. In this study, we analyzed the collision risk of the UAM corridor according to the lateral separation distance using a collision risk model used to analyze the collision risk of manned aircraft parallel routes for a similar type of UAM corridor. Based on this, we finally analyzed how many parallel routes could be installed within the width of the Han River, considering the K-UAM demonstration route.

A Study on the Cultural Exchange of the Weaving Skills and Patterns Witnessed in Geum-textiles between the East and West - from Ancient Times to the Tang Dynasty - (제직기술과 문양을 통해 본 금직물(錦織物)의 동서교류에 관한 연구 - 고대부터 당시대를 중심으로 -)

  • Shin, Hey-Sung
    • Journal of the Korean Society of Costume
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    • v.62 no.4
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    • pp.107-122
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    • 2012
  • The purpose of this study is to investigate the changes and developments that occurred as a result of the exchanges of gyeong-geum(經錦), a warp-faced compound weave of East Asia, and wie-geum(緯錦), a weft-faced compound weave of West Asia. In order to maximize the efficiency of this research, topics were narrowed down to the weaving skills and patterns, and the period was limited to the Tang dynasty. The systematic characteristics and differences of gyeong-geum and wie-geum were compared and contrasted through different works of literature. Then the excavated remains of geum-textiles were analyzed and the characteristics of the geum-textiles were defined in chronological order. The origin of wie-geum is traced back to the time when West Asia started to imitate the weaving style of the East Asian gyeong-geum. When combined with the weaving skills of the West Asian, gyeong-geum, which broke through the West and developed into the weft-faced compound twill silk, or samite. The exchange of geum-textiles took place as the techniques of gastric filament woven geum-textiles returned to the East. Along with the pearl roundel motifs of Sassanian Persia, mythical animals and western motifs of hunter patterns were used for the patterns of wie-geumin during the early Tang dynasty. This tendency is related to pa-sa-geum(波斯錦), ho-geum(胡錦), beon-geum(番錦) according to the recorded literature. The 8th and 9th century are periods when the West Asian Persian style was abandoned and the East Asian style, samite, was established. Not only did S twist silk threads replace Z twists, but also the repetition of patterns unfolded along with the weft and the warp. As this tendency was strengthened after the 9th century, the expression of patterns became more vividly colorful and showed both elements of naturalism and realism. The characteristics of the Bosangwha(寶相花) pattern in the Tang period were established with the rampantly repeated rosettes with birds often holding auspicious branches, that fly amid floral compositions.

A Study on the Response Plan through the Analysis of North Korea's Drones Terrorism at Critical National Facilities - Focusing on Improvement of Laws and Systems - (국가중요시설에 대한 북한의 드론테러 위협 분석을 통한 대응방안 연구 - 법적·제도적 개선을 중심으로 -)

  • Choong soo Ha
    • Journal of the Society of Disaster Information
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    • v.19 no.2
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    • pp.395-410
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    • 2023
  • Purpose: The purpose of this study was to analyze the current state of drone terrorism response at such critical national facilities and derive improvements, especially to identify problems in laws and systems to effectively utilize the anti-drone system and present directions for improvement. Method: A qualitative research method was used for this study by analyzing a variety of issues not discussed in existing research papers and policy documents through in-depth interviews with subject matter experts. In-depth interviews were conducted based on 12 semi-structured interviews by selecting 16 experts in the field of anti-drone and terrorism in Korea. The interview contents were recorded with the prior consent of the study participants, transcribed back to the Korean file, and problems and improvement measures were derived through coding. For this, the threats and types were analyzed based on the cases of drone terrorism occurring abroad and measures to establish anti-drone system were researched from the perspective of laws and systems by evaluating the possibility of drone terrorism in the Republic of Korea. Result: As a result of the study, improvements to some of the problems that need to be preceded in order to effectively respond to drone terrorism at critical national facilities in the Republic of Korea, have been identified. First, terminologies related to critical national facilities and drone terrorism should be clearly defined and reflected in the Integrated Defense Act and the Terrorism Prevention Act. Second, the current concept of protection of critical national facilities should evolve from the current ground-oriented protection to a three-dimensional protection concept that considers air threats and the Integrated Defense Act should reflect a plan to effectively install the anti-drone system that can materialize the concept. Third, a special law against flying over critical national facilities should be enacted. To this end, legislation should be enacted to expand designated facilities subject to flight restrictions while minimizing the range of no fly zone, but the law should be revised so that the two wings of "drone industry development" and "protection of critical national facilities" can develop in a balanced manner. Fourth, illegal flight response system and related systems should be improved and reestablished. For example, it is necessary to prepare a unified manual for general matters, but thorough preparation should be made by customizing it according to the characteristics of each facility, expanding professional manpower, and enhancing response training. Conclusion: The focus of this study is to present directions for policy and technology development to establish an anti-drone system that can effectively respond to drone terrorism and illegal drones at critical national facilities going forward.

The change of designation and release of Hapcheon (Gyeongsangnam-do) Swan Sanctuary as Natural Monument (천연기념물 합천 백조도래지의 지정과 해제과정)

  • SIM Keunjeong
    • Korean Journal of Heritage: History & Science
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    • v.57 no.1
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    • pp.162-178
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    • 2024
  • Swans are representative migratory birds that spend winter in East Asia, and have long been considered rare birds. In particular, they were regarded as king of Japan. The process of designating a natural monument in Hapcheon Swan Sanctuary is an interesting story. In this study, the designation and release process of Hapcheon Swan Sancturay ((Bakgok-ji, Yongju-myeon 龍州面 朴谷池), (Jeongyang-ji, Daeyang-myeon 大陽面 正陽池), Gaho, Cheongdeok-myeon 淸德面 嘉湖)) Natural Monument, was examined. These places were designated as a natural monument on August 27, 1934, during the Japanese colonial period, and was lifted on August 14, 1973, after the Cultural Protection Act was enacted after liberation. From the beginning of the new year in 1929, the Japanese Government-General of Korea (朝鮮總督府) decided to capture swans alive to give to the king of Japan. An official of the Japanese Government-General of Korea (統監) decided to offer swans to the king during his New Year's greeting visit. The department in charge of capturing swans was the Gyeongsangnam-do Provincial Police Department, and the execution was the police station of each county (郡). The reason is believed to be that it is easy to forcibly mobilize, control, or urge people, and the capture activity had to be completed as soon as possible. A total of three swans were captured in Hapcheon-gun from January 12 to 14, 1929. At that time, various newspapers published related information. Based on these facts and experiences, it is estimated that the Hapcheon area was selected when designating a natural monument in 1934. Hapcheon Swan Sancturay, Natural Monument lost its function due to excessive human interference of various developments, illegal capture, and use of poison to catch swans. Their number has also significantly decreased. It was thus removed from the natural monument in 1973. One of the three swan sanctuaries (Gaho 嘉湖) has been completely reclaimed, one (Bakgok-ji 朴谷池) has almost no migratory birds due to the conversion of wetlands, and one (Jeongyang-ji 正陽池) has swans flying back. In the case of Jeongyangji (正陽池), It is an encouraging sign that many swans fly as the surrounding environment and growing conditions change. This phenomenon is interpreted to mean that nature and climate are recovering and healing.