• 제목/요약/키워드: Salt field

검색결과 312건 처리시간 0.032초

한반도의 곰솔분포에 관한 연구 (A Study on the Distribution of Pinus thunbergii in the Korean Peninsula)

  • Kim, Jung Un;Bong-Seop Kil
    • The Korean Journal of Ecology
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    • 제6권1호
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    • pp.45-54
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    • 1983
  • A distribution map of black pine, Pinus thunbergii, in south Korea was prepared through field surveys. According to Mirov(1967), the range of black pine is limited in east Asia, Japan and Korea; its northern limit is at about 41。34' north and its southern limit on Takara island, south Kyushu, at 29。 north. According to the present map, its northern limit coincided with the isopath of warmth index 100 by Yim(1977). The density of pine in grid mesh, about 4 km * 4 km, was higher at costal area than that in inland area, and it was also higher at sea side slope than the opposite slope of the same mountain. This suggests that the ecological distribution of black pine is greatly affected by salt content of the soil or the optimal range of summed temperature for the pine growth.

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군산지역 준설토의 퇴적특성 (Deposition Properties of Dredged Materials of Kun-Jang Industrial Complex)

  • 한영철;송정락
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 1992년도 가을학술발표회 논문집
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    • pp.61-64
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    • 1992
  • Recently, by the lack of fill material, the dredg and fill(hydraulic fill) method is commonly used in reclamation projects. Hydraulic fill method dredges the soil and send it with water through the transportation pipe to the site. The intial state of the hydraulic fill material is accordingly the mixture of water and soil skeleton which settles with time forming a new soil layer. The properties of new soil layer is governed the size of the soil skeleton, the flow velocity of mixing water, salt concentration, the distance from the discharge pipe outlet, and other dredging conditions when settling process occur. In this study, the effects of gradation of derdged soil on the deposition properties (with emphasis on the optimum spacing of the discharge pipes) was investigated by field test. It was found that the soft fine graind soil was forme at 350m from the discharge pipe outlet when the dredged material was classified as CL, while the soft fine grained soil was not formed even at the distance farther than 400m from the diacharge pipe outlet when the dredged material was classified as SM.

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송전용 애자의 인공오손시험 기법과 누설전류 특성 (Artificial contaminated test method and leakage current characteristics of EHV insulators)

  • 최인혁;정윤환;최장현;이동일
    • 한국조명전기설비학회:학술대회논문집
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    • 한국조명전기설비학회 2004년도 춘계학술대회 논문집
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    • pp.386-391
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    • 2004
  • To find out the reason of accident by being stained of insulators, this paper researched and analyzed the result of electrical characteristic test and field test of EHV insulator through artificial contaminated method. The best way to evaluate contaminated level of insulator surface is getting a contamination data by regional groups continually. But it is needed a lot of time and manpower. To overcome those difficulties, this research introduced ESDD(equivalent salt deposit density) measurement method which is adapted to the international codes of IEC and compared the relation between experimental test results which contaminated insulators by going through stain procedure and electrical measurement results.

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오염물질에 따른 변압기부싱 모델의 기중 코로나 방전 특성 (Corona Discharge Characteristics of Transformer Bushing Model with Contaminnations in Air)

  • 방만식;김우진;김영석;김상현
    • 조명전기설비학회논문지
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    • 제26권5호
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    • pp.91-96
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    • 2012
  • The surface of bushing is contaminated with rain, dust, salt and others. A bushing with contaminations in air is serious problem in insulation. Therefore, it is important to understand the inspection and diagnoses of the safety. The ultra-violet rays(UV) camera has attracted interest from the view point of easy judgement. In this paper, we will report on the corona discharge characteristics of surface flashover model with contaminations in air. Also, UV images of discharge and corona pulse count in air are analyzed using prototype UV camera of Korea and a UV sensor with an optic lens. These results are studied at both AC and DC voltage under a non-uniform field.

IMAGE ENCRYPTION USING NONLINEAR FEEDBACK SHIFT REGISTER AND MODIFIED RC4A ALGORITHM

  • GAFFAR, ABDUL;JOSHI, ANAND B.;KUMAR, DHANESH;MISHRA, VISHNU NARAYAN
    • Journal of applied mathematics & informatics
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    • 제39권5_6호
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    • pp.859-882
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    • 2021
  • In the proposed paper, a new algorithm based on Nonlinear Feedback Shift Register (NLFSR) and modified RC4A (Rivest Cipher 4A) cipher is introduced. NLFSR is used for image pixel scrambling while modified RC4A algorithm is used for pixel substitution. NLFSR used in this algorithm is of order 27 with maximum period 227-1 which was found using Field Programmable Gate Arrays (FPGA), a searching method. Modified RC4A algorithm is the modification of RC4A and is modified by introducing non-linear rotation operator in the Key Scheduling Algorithm (KSA) of RC4A cipher. Analysis of occlusion attack (up to 62.5% pixels), noise (salt and pepper, Poisson) attack and key sensitivity are performed to assess the concreteness of the proposed method. Also, some statistical and security analyses are evaluated on various images of different size to empirically assess the robustness of the proposed scheme.

Transcriptome analysis of internal and external stress mechanisms in Aster spathulifolius Maxim.

  • Sivagami, Jean Claude;Park, SeonJoo
    • 한국자원식물학회:학술대회논문집
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    • 한국자원식물학회 2019년도 춘계학술대회
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    • pp.35-35
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    • 2019
  • Aster spathulifolius Maxim. is belongs to the Asteraceae family which is distributed only in Korea and Japan. It is recognize as a traditionally medicinal plants and economically valuable in ornamental field. However, among the Asteraceae family, the Aster genus, which is lacks in genomic resources and information of molecular function. Therefore, we used high throughput RNA-sequencing transcriptome data of the A. spathulifolius to know molecular level function. DeNovo assembly produced 98,660 unigene with N50 value 1126 bp. Unigenes was performed to analyses the functional annotation against NCBI database like plant database of nucleotide (Nt) and non-redundant protein (Nr), Pfam, Uniprot, KEGG and Transcriptional factor (TF). In addition, Distribution of SSR markers also analyzed for future perfectives. Further, Comparing with other two Asteraceae family species like, Karelinia caspica and Chrysanthemum morifolium to the A. spathulifolius shows the number of gene that regulated in internal and external stress respectively salt-tolerant and heat and drought stress to understand the molecular basis related to the different environments stress.

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Mechanical properties of stabilized saline soil as road embankment filling material

  • Li Wei;Shouxi Chai;Pei Wang
    • Geomechanics and Engineering
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    • 제37권5호
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    • pp.499-510
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    • 2024
  • In northern China, abundant summer rainfall and a higher water table can weaken the soil due to salt heave, collapsibility, and increased moisture absorption, thus the chlorine saline soil (silty clay) needs to be stabilized prior to use in road embankments. To optimize chlorine saline soil stabilizing programs, unconfined compressive strength tests were conducted on soil treated with five different stabilizers before and after soaking, followed by field compaction test and unconfined compressive strength test on a trial road embankment. In situ testing were performed with the stabilized soils in an expressway embankment, and the results demonstrated that the stabilized soil with lime and SH agent (an organic stabilizer composed of modified polyvinyl alcohol and water) is suitable for road embankments. The appropriate addition ratio of stabilized soil is 10% lime and 0.9% SH agent. SH agent wrapped soil particles, filled soil pores, and generated a silk-like web to improve the moisture stability, strength, and stress-strain performance of stabilized soil.

친환경 제설제의 융빙성능 평가 (Evaluation of Deicing Performance for the Eco-Friendly Deicer)

  • 이경배;이승우;유형목;박희문
    • 한국도로학회논문집
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    • 제10권2호
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    • pp.15-26
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    • 2008
  • 최근 들어 철근 부식, 콘크리트 포장표면의 박리파손, 환경 피해 등 염화물계 제설제의 사용에 따른 각종 피해가 보고되고 있으며, 이를 위해 대체 제설제의 개발을 위한 연구가 활발히 진행되고 있다. 하지만 개발된 제설제의 성능평가에 대한 연구는 대부분 실내실험을 위주로 한 기초적이고 제한적인 성능평가에 의존하고 있는 선정이다. 특히 제설제의 융빙성능은 제설제가 갖추어야 할 기본적인 성능으로, 합리적이고 체계적인 평가방법을 통한 융빙성능의 평가가 필수적이다. 본 연구에서는 기존 연구를 바탕으로 보다 구체적이고 현실적인 융빙성능 평가방법을 수립하였으며 그 절차에 따라 본 연구진에 의해 개발된 저염화물계 친환경 제설제인 EFD(Eco Friendly Deicer)의 융빙성능을 평가 및 검증하였다. 실내실험 결과, EFD는 국내 고속도로에서 사용 중인 습염식 제설제와 대등한 수준의 초기 융빙성능을 나타냈으며 2회의 현장살포 실험을 통해 EFD의 융빙성능을 검토한 결과, 전체적인 융빙성능이 습염식 제설제의 융빙 성능에 비해 큰 차이가 없음을 확인하였다.

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만구를 통한 해수유출입과 만내수괴의 해수교환성 (Cross-Sectional Velocity Variability and Tidal Exchanger in a Bay)

  • 김종화
    • 수산해양기술연구
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    • 제26권4호
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    • pp.353-359
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    • 1990
  • 물리적, 지형적 특성으로 구성되고 있는 만내수괴의 유출입 구조와 해수의 교환능력을 정량적으로 구하기 위해, 진해만과 그 부속 내만을 대상으로 하여 현지관측에 근거해서 다음과같은 결과를 얻었다. 1. 가덕수도 단면의 유출입 특성은 유출수괴의 유축은 1조석주기동안 남북으로 2회 왕복운동을 진행하며, 대체로 하층에 존재한다. 유입수괴의 유축은 남부와 북부에 양분되어 존재하는 경향이다. 전 시간에 걸쳐 반류현상으로 보이는 유출입 수괴가 동시에 존재한다. 2. 양 수도를 통한 해수유출입량의 비율은 가덕수도에서 대조기 약 86~90% 소조기 61~80%유출입된다. 따라서, 가덕수도를 통한 수괴의 유출입이 만의 해수교류.교환을 지배한다. 3. 하계만의 해수교환율은 양 수도에서 대조기 12~13%, 소조기 20%이상이나, 마산만 입구에서는 대조기 9%, 소조기 2%정도에 불과하다. 4. 하구역 특성으로 본 해수교환기구는, 가덕수도가 흐름은 깊이에 따라 방향이 변하고 약간 성층되나, 잘 혼합된 염분분포를 나타내어 salt flux는 주로 이류에 의존한다. 마산만은 sill의 해저지형가 만 입구에서 tidal trapping 현상으로, 고도의 성층된 상태를 보이고 있다.

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대장균군 검사용 간이 시험지 개발 (A Study on the Development of Microorganism Test Strips)

  • 이인애;김재화;이희구;성창근;최인성;정태화
    • 대한의생명과학회지
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    • 제2권1호
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    • pp.49-55
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    • 1996
  • 대장균군 검사용 간이 시험지는 본 실험실에서 국내 최초로 고안, 개발하였으며 이 간이 시험지법은 현장 검사법의 하나로 대장균군이 내는 succinic acid dehydrogenase 때문에 tetrazolium salt가 환원되어 적색 반점을 형성하는 것을 이용한 방법으로서 이 간이 시험지의 제조는 대체로 종래의 표준 평판법과 거의 동일한 조성의 배지와 시약을 사용하여 여지에 흡착시킨 후, 건조시켜($60^\circ$C) 멸균한 것으로 표준 평판법과 어떤 상관관계가 있는가를 검토하였다. 이 간이 시험지의 제조에서는 bile salt No. 3를 deoxycholate로 대체하여 제조 원가를 절감하였고, 또한 일본에서 현재 시판되고 있는 제품과 품질 비교시험을 하여 더 좋은 결과를 얻었으며 종래의 표준 평판법과 비교하였을 때도 오히려 표준 평판법 (24-48시간 배양)보다 빠른 시간(16-20시간 배양)내에 판정할 수 있는 이 점이 있으며, 표준 평판법에서는 없어서는 안될 배지나 배양 접시, pipette등의 자료 및 기구가 일체 필요없고 언제 어디서나 현장에서 직접 시험할 수 있어 매우 간편하며 또한 저렴한 가격으로 제조 할 수 있는 경제성이 높은 이점을 갖고 있다.

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