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Palaeomagnetism of Cretaceous Rocks in the Ǔisǒng Area, Kyǒngsang Basin, Korea (의성지역 백악기 암석에 대한 고자기 연구)

  • Kim, In-Soo;Lee, Hyun Koo;Yun, Hyesu;Kang, Hee-Cheol
    • Economic and Environmental Geology
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    • v.26 no.3
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    • pp.403-420
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    • 1993
  • The Cretaceous Kyongsang Basin is known to be composed of several tectonic blocks (or subbasins) with each distinct stratigraphic succession. The study area represents a major part of one of these blocks, i. e. the $\check{U}is\check{o}ng$ block. The area is charaterized by a suite of WNW-trending sinistral strike-slip faults as well as a number of ring faults. A total of 292 independently oriented core samples were drilled from 23 sites, covering virtually all the formations of the Cretaceous $Ky\check{o}ngsang$ Supergroup. Alternating field and thermal demagnetization experiments were conducted to reveal the primary magnetization. Due to the homoclinal nature of the strata in the area, it was not possible to make use of the conventional fold test It is, however, believed that the primary remanent components have been obtained from the majority of the formations, considering the similarity of the palaeomagnetic pole positions with those of contemporary strata of other blocks and the existence of antiparallel reversed remanence. It was found neither any significant difference in magnetic declination on each side of the strike-slip faults nor systematic change of magnetic declination with distance from the fault-line. This does not support such a block rotation hypothesis associated with the strike-slip faulting in the area as alleged by some authors. The samples from the outcrops on or near the fault-lines were severely overprinted by the recent magnetic fields regardless of age and lithology. Epithermal Au-Ag-Cu-Pb-Zn mineralizations are known along some fault lines in the area. It is interpreted that these two facts are closely related with fluid circulations along the fracture zones caused by fault activities. In regard to the age of the strata as deduced from the magnetostratigraphic consideration, the $Ch\check{o}mgok$ formation and the lower strata should be older than Barremian or 124 Ma. The age of volcanics of the $Yuch^{\prime}\check{o}n$ Group sampled in this study should be younger than Campanian or 83 Ma.

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Ohmic Heating Characteristics of Fermented Soybean Paste and Kochujang (된장 및 고추장의 Ohmic heating 특성)

  • Cho, Won-Il;Kim, Do-Un;Kim, Young-Suk;Pyun, Yu-Ryang
    • Korean Journal of Food Science and Technology
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    • v.26 no.6
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    • pp.791-798
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    • 1994
  • Ohmic heating is a food processing operation in which heat is internally generated within foods by the passage of alternating electric current. The process enables highly viscous paste foods such as Kochujang, and fermented soybean paste to be heated very fast. In order to develope the novel pasteurization process of paste foods, static Ohmic heating system was built, and heating characteristic during Ohmic heating under various conditions were studied. Electric conductivities of Kochujang and fermented soybean paste at room temperature were 1.865 S/m and 2.510 S/m, respectively and increased linearly with increasing temperature. Specific heating rate was highly dependent on the frequency. The highest heating rate was achieved at 5 KHz for Kochujang and 20 KHz for fermented soybean paste. Uniform heating throughout the sample was achieved during Ohmic heating with low frequency electrical currents, however above 5 KHz frequency, surface temperature was several degrees higher than the bulk.

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Studies on the Myofibrillar Proteins Part I. Phase Microscopy of Myofibrils from Rabbit Muscle (근원섬유 단백질에 관한 연구 (제1보) 근원섬유에 관한 형태학적 연구)

  • Yang, Ryung;Kim, Chul-Jai;Moon, Yoon-Hee;Yu, Ju-Hyun
    • Korean Journal of Food Science and Technology
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    • v.6 no.2
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    • pp.79-85
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    • 1974
  • To obtain further information concerning the nature myofibrillar proteins in a food system, an investigation has been conducted to compare the change in the biochemical property of the myofibril with the changes in the morphological structure of the myofibril. When myofibrils were prepared with 0.16 M KCl-0.04 M Tris-HCl, the band pattern was clear and distinct. There was a uniform thickening of A-band, a sharp appearence of Z-lines and a wide I-band. The band pattern of myofibrils was changed as the composition of extraction solution was changed. Also the ATPase activity of myofibril changed as the length of sarcomere changed. When myofibrils were treated with a low concentration of trypsin, myofibrils turned in the contracted state. With the progress of prolonged trypsin treatment, most of myofibrils exhibited a pattern of alternating light and dark bands, supercontracted pattern. Although myofibrils exhibited a supercontracted band pattern, the ATPase activity of myofibril continued to increase with the progress of trypsin treatment. An assumption was made that tropomyosin may be located in Z-line and that troponin-tropomyosin complex can inhibit the ATPase activity of myofibrils through the structural alternation of myofibril.

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Surface Ultrastructure of Heterophyes nocens (Trematoda: Heterophyidae) (Heterophues nocens (Trematoda: Heterophyidae)의 표피 미세구조)

  • 채종일;정혜림
    • Parasites, Hosts and Diseases
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    • v.30 no.2
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    • pp.75-82
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    • 1992
  • The surface ultrastructure of Heterephyes nocens (Trematoda: Heterophyidae) was studied by scanning electron microscopy(SEM), The adult worms were recovered from experimentally infected cats and from a naturally infected patient. They were leaf-like, ventrally concave, and ovoid or lyriform in shape. Ciliated knob-like sensory papillae (type I) were observed in single or grouped forms on and around the oral sucker, whereas non-ciliated round swellings (type II papillae) were seen on the lip of the ventral sucker, The tegumental spines around the oral sucker were 5∼9 pointed, whereas those between the two suckers were 12∼17 pointed. yentrolaterally, three groups of 5∼6 type I papillae were located between the oral and ventral suckers, with single ones alternating between them. The genital sucker was protruded or depressed, depending on the contraction state of the nukes, and the gonotyl spine number ranged 50∼60. The number of tip points of tegumental spines was decreased posteriorly; finally they became 1∼3 pointed. On the dorsal surface, 4 groups of 4∼5 type I papillae were symmetrically located on both lateral sides, and the shape and distribution of tegumental spines were similar to those of the ventral surface. Although the tegumental ultrastructure of H. nocens was generally similar to those of other heterophyids, the genital sucker morphology including the number of gonotyl spines and/or the distribution pattern of tegumental spines and sensory papillae were suggested to be the characteristic features of H. necens.

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Analysis of the Weediness Potential in Vitamin A Enforced Rice (비타민 A 강화 벼의 잡초화 가능성 분석)

  • Lee, Hyun-Suk;Yi, Gi-Hwan;Park, Jong-Sug;Seo, Suk-Cheol;Sohn, Jae-Keun;Kim, Kyung-Min
    • Korean Journal of Weed Science
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    • v.31 no.2
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    • pp.160-166
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    • 2011
  • The purposes of this study were to analyze the weediness potential associated with 'Vitamin A enforced rice' and to evaluate the relationships between growth characteristics and environmental adaption related to survival ability in the natural environment. 'Vitamin A enforced rice', 'Nagdong', donor variety of 'Vitamin A enforced rice' and three other varieties were used for this study. The 'Vitamin A enforced rice' was experimented according to ratio of ripened grain, shattering of grain, germination traits, germination ratio of low temperature, emergence ratio after wintering, ratio of viviparity, and growth ratio after ratooning ability. 'Vitamin A enforced rice' was not significant between 'Nagdong' and other varieties in seven characters. Germination ratio was similar of Vitamin A enforced rice' and 'Nagdong', but average germination ability of was different at low temperature. Also, shattering of grain and germination ratio of alternating temperature were significant between 'Nagdong' and other varieties. These results suggested that the relationships between growth characteristics and environmental adaption in 'Vitamin A enforced rice' could be applied to the stability of weediness potential and biosafety guide in GM rice.

Evaluation on the nutrient concentration changes along the flow path of a free surface flow constructed wetland in agricultural area (농업지역에 조성된 자유수면형 인공습지의 유로에 따른 영양염류의 변화 평가)

  • Mercado, Jean Margaret R.;Maniquiz-Redillas, Marla C.;Kim, Lee-Hyung
    • Journal of Wetlands Research
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    • v.15 no.2
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    • pp.215-222
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    • 2013
  • In this study, the nutrient concentration changes along the hydrologic flow path of a free water surface flow constructed wetland (CW) treating agricultural stream runoff was investigated. Dry sampling was performed from April 2009 to November 2011 at five locations representing each treatment units of the CW. Grab water samples were analyzed for nitrogen forms such as total nitrogen (TN), total Kjeldahl nitrogen, nitrate, and ammonium; and phosphorus forms including total phosphorus (TP) and phosphate. Findings revealed that the physical properties such as temperature, dissolved oxygen and pH affected the TP retention in the CW. High nutrient reduction was observed after passing the first sedimentation zone indicating the importance of settling process in the retention of nutrients. However, it was until the 85% of the length of the CW where nutrient retention was greatest indicating the deposition of nutrients at the alternating shallow and deep marshes. TN and TP concentration seemed to increase at the final sedimentation zone (FSZ) suggesting a possible nutrient source in this segment of the CW. It was therefore recommended to reduce or possibly remove the FSZ in the CW for an optimum performance, smaller spatial allocation and lesser construction expenses for similar systems.

Studies on Alternaria and Corynespora Blights of Sesame (참깨 검은무늬병(病) 및 잎마름병(病)에 관한 연구(硏究))

  • Yu, Seung-Heon;Kim, Hong-Gi;Gang, Yeo-Gyu;Park, Jong-Seong
    • The Korean Journal of Mycology
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    • v.9 no.4
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    • pp.169-176
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    • 1981
  • Survey of sesame crop in the cultivators' field in the district of Daejeon, Yuseong, Sintanjin, Nonsan and Keumsan revealed that Alternaria and Corynespora blights of sesame were wide spread and caused severe damage to sesame plants. Symptoms of a new disease of sesame in Korea caused by Alternaria sesami were spreading, dark-brown to black, water-soaked lesions which often could be traced the entire length of the stem. In severe infections, several lesions coalesced together involving a major portion of the blade and the infected leaves dried and usually dropped off. Symptoms of Corynespora blight, caused by Corynespora cassiicola, were irregular shaped, concentrically-zoned, light brown to reddish brown lesions which later coalesced and caused defoliation. Stem lesions were long, reddish brown streaks that often coalesced, blighting the plants. The optimum temperatures for mycelial growth of A. sesami and C. cassiicola were about $27^{\circ}C$ and sporulations of these 2 fungi were stimulated under alternating light and darkness. Mycelial growth and sporulation of A. sesami and C. cassiicola were the greatest on sesame oatmeal agar (SOA) and potato dextrose agar (PDA), respectively.

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Fabrication of Silicon Quantum Dots in Si3N4 Matrix Using RF Magnetron Co-Sputtering (RF 마그네트론 코스퍼터링을 이용한 Si3N4 매트릭스 내부의 실리콘 양자점 제조연구)

  • Ha, Rin;Kim, Shin-Ho;Lee, Hyun-Ju;Park, Young-Bin;Lee, Jung-Chul;Bae, Jong-Seong;Kim, Yang-Do
    • Korean Journal of Materials Research
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    • v.20 no.11
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    • pp.606-610
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    • 2010
  • Films consisting of a silicon quantum dot superlattice were fabricated by alternating deposition of silicon rich silicon nitride and $Si_3N_4$ layers using an rf magnetron co-sputtering system. In order to use the silicon quantum dot super lattice structure for third generation multi junction solar cell applications, it is important to control the dot size. Moreover, silicon quantum dots have to be in a regularly spaced array in the dielectric matrix material for in order to allow for effective carrier transport. In this study, therefore, we fabricated silicon quantum dot superlattice films under various conditions and investigated crystallization behavior of the silicon quantum dot super lattice structure. Fourier transform infrared spectroscopy (FTIR) spectra showed an increased intensity of the $840\;cm^{-1}$ peak with increasing annealing temperature due to the increase in the number of Si-N bonds. A more conspicuous characteristic of this process is the increased intensity of the $1100\;cm^{-1}$ peak. This peak was attributed to annealing induced reordering in the films that led to increased Si-$N_4$ bonding. X-ray photoelectron spectroscopy (XPS) analysis showed that peak position was shifted to higher bonding energy as silicon 2p bonding energy changed. This transition is related to the formation of silicon quantum dots. Transmission electron microscopy (TEM) and electron spin resonance (ESR) analysis also confirmed the formation of silicon quantum dots. This study revealed that post annealing at $1100^{\circ}C$ for at least one hour is necessary to precipitate the silicon quantum dots in the $SiN_x$ matrix.

Characteristics of SiO2/Si Quantum Dots Super Lattice Structure Prepared by Magnetron Co-Sputtering Method (마그네트론 코스퍼터링법으로 형성한 SiO2/Si 양자점 초격자 구조의 특성)

  • Park, Young-Bin;Kim, Shin-Ho;Ha, Rin;Lee, Hyun-Ju;Lee, Jung-Chul;Bae, Jong-Seong;Kim, Yang-Do
    • Korean Journal of Materials Research
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    • v.20 no.11
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    • pp.586-591
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    • 2010
  • Solar cells have been more intensely studied as part of the effort to find alternatives to fossil fuels as power sources. The progression of the first two generations of solar cells has seen a sacrifice of higher efficiency for more economic use of materials. The use of a single junction makes both these types of cells lose power in two major ways: by the non-absorption of incident light of energy below the band gap; and by the dissipation by heat loss of light energy in excess of the band gap. Therefore, multi junction solar cells have been proposed as a solution to this problem. However, the $1^{st}$ and $2^{nd}$ generation solar cells have efficiency limits because a photon makes just one electron-hole pair. Fabrication of all-silicon tandem cells using an Si quantum dot superlattice structure (QD SLS) is one possible suggestion. In this study, an $SiO_x$ matrix system was investigated and analyzed for potential use as an all-silicon multi-junction solar cell. Si quantum dots with a super lattice structure (Si QD SLS) were prepared by alternating deposition of Si rich oxide (SRO; $SiO_x$ (x = 0.8, 1.12)) and $SiO_2$ layers using RF magnetron co-sputtering and subsequent annealing at temperatures between 800 and $1,100^{\circ}C$ under nitrogen ambient. Annealing temperatures and times affected the formation of Si QDs in the SRO film. Fourier transform infrared spectroscopy (FTIR) spectra and x-ray photoelectron spectroscopy (XPS) revealed that nanocrystalline Si QDs started to precipitate after annealing at $1,100^{\circ}C$ for one hour. Transmission electron microscopy (TEM) images clearly showed SRO/$SiO_2$ SLS and Si QDs formation in each 4, 6, and 8 nm SRO layer after annealing at $1,100^{\circ}C$ for two hours. The systematic investigation of precipitation behavior of Si QDs in $SiO_2$ matrices is presented.

Automated Negotiation Model among Agents Using Extended Alternating-Offer Game in Electronic Commerce (전자상거래에서 확장된 교차제의 게임을 이용한 에이전트간 자동협상 모델)

  • 정종진;조근식
    • Journal of Intelligence and Information Systems
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    • v.8 no.1
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    • pp.103-117
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    • 2002
  • Recently, many researchers have developed applications for automated contract and negotiation using agent technologies on electronic commerce. Especially, they have tried to study negotiation mechanism applying agent instead of buyers and sellers. Traditional researches, however, often had limitations. In the researches of automated negotiation, the agents had to negotiate with the other agents for a simple negotiation issue because the mechanisms were naive. In the researches of negotiation by user interaction, the agents did not have supported the procedures and methodologies for making the automated negotiation but only supported the users by providing communication environment during the negotiation process by users. In this paper, we propose efficient negotiation model using the modified negotiation model of the game theory. In the proposed model, the agents negotiate automatically with the partner agent and make good benefits by the strategic method during the negotiation process. Each agent makes negotiation issues with user's requirements and exchanges its suggestion alternatively in each step of the negotiation process. The agent evaluates degree of satisfaction for the opposite's suggestion and uses it in the next step of suggestion. To find out the negotiation strategies of opposite side, the agent uses teaming by weights of issues. As a result, the agent improves each own benefits for the contract and reduces the unbalance of its benefits through the proposed negotiation mechanism. We implement the negotiating agents according to the proposed mechanism and prove the efficiency of the proposed model by various experimentation.

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