• Title/Summary/Keyword: Salt field

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A STUDY ON THE GROWTH OF THE MUSSEL, Mytilus edulis, IN A SALT-FIELD RESERVOIR (염전 저수지에서의 진주담치 (Mytilus edulis) 생장에 관한 연구)

  • LEE Choonkoo;KO Yong Soon;LEE Jong Kook
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.5 no.3
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    • pp.71-75
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    • 1972
  • The growth of the mussel, Mytilus edulis, in a salt-field reservoir was investigated at Dangjin, Choongnam, from June to October in 1970. l. Temperature, salinity, specific gravity, and pH of water were $22.5-27.5^{\circ}C,\;28.6-34.8\%$, 1.019-1.024, and 7.6 respectively in the salt-field reservoir from June 20 to July 19. 2. Three species of Gastropoda and seven species of Pelecypoda were collected. 3. The shell height of the mussel group in the highest abundance increased from 200mm($15\~25mm$) on June 15 to 40mm ($20\~50mm$) on September 26 in the salt-field reservoir, whereas the average shell heights of them were 19.80mm (June 15) and 35. 10mm (Sept. 26) respectively. 4. The daily growth of the mussel from July 10 to August 12 was 0.22 mm in shell height and highest during the experimental period. 5. The relationships between shell length (L) and shell height (H), and between shell length (L) and shell breadth (B) of the young mussel are represented by the following equations respectively : H=1.26776L+5.07978 B=35041L+3.05502 6. From the above results, it is suggested that the culture of the mussell, Mytilus edulis, in a salt-field reservoir is possible.

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Salinity and water level measuring device using fixed type buoyancy (고정식 부력을 이용한 염도 및 수위 측정 방식에 대한 연구)

  • Yang, Seung-Young;Byun, Kyung-Seok
    • Journal of the Institute of Convergence Signal Processing
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    • v.21 no.1
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    • pp.1-6
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    • 2020
  • To make an automated system for a salt field, it is necessary to measure the salinity and water level of the evaporation site. In this paper, a method to simultaneously measure the salinity and water level by measuring the buoyancy forces of two fixed buoyancy bodies is proposed. The proposed measurement method measures the buoyancy of the main part and reference part when the measuring device is immersed in the salty water, and simultaneously measures the salinity and water level through the sum and difference of the two buoyancy forces. Since there is no mechanical movement in the measurement of buoyancy, measurement errors and maintenance needs can be reduced in the mudy environment of salt field. By applying the proposed method, we developed a system that can simultaneously measure salinity and water level remotely at the evaporation site of a salt field. Through a measurement experiment using a reference salty water having various levels of salinity, the results of a salinity error of 0% and a water level error of 2mm were obtained, and the effectiveness of the proposed salinity and water level measuring device was verified. When an automated system is constructed using the developed salinity and water level measuring device, labor reduction, work environment improvement, and productivity improvement are expected.

A study on Sea-salt distribution of High-rise Apartments in Waterfront Area (워터프런트 지역 고층아파트의 해염분포에 관한 연구)

  • Doe, Geun-Young;Lee, Han-Seok;Song, Hwa-Cheol
    • KIEAE Journal
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    • v.6 no.1
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    • pp.33-38
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    • 2006
  • The purpose of this study is to investigate the concentration of sea-salt distribution giving great characteristic environmentally. Therefore the field measurement was conducted to target high-rise apartments constructing in reclaimed land of Busan and measured the concentration of sea-salt by means of distance and height of high-rise apartments from coast. The results of this study were as follows ; 1) The more a horizontal distance is far from coast, the more concentration sea-salt become low. But this study can not draw conclusion exactly as differ from a tendency of the thing close to the coast and the land. 2) In the near seaside, No.132 apartment accords existing research result that in difference of the concentration of sea-salt by height, the more height is high, the more that is high. But in seaside, No.117 apartment of middle point appears that the upper story and the lower story than middle story. Once more, in inland, No.132 apartment and No.117 apartment tend toward opposite it of the seaside. The reason that the result of this measurement and existing study is not agreement is thought that it occurs to turbulent flow between apartments by construction of high-rise apartments group.

Recovery of Sodium Sulfate from Farm Drainage Salt and Using It in Direct Dyeing of Cotton - Analysis of Color Difference -

  • Jiyoon Jung
    • The International Journal of Costume Culture
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    • v.4 no.1
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    • pp.18-24
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    • 2001
  • Agricultural drainage salt generated during irrigation of crops in San Joaquin Valley, California, exceeds 600,000 tons annually and cumulates in the field in a rapid rate. As a result, the waste is taking out more farmlands for salt storage and disposal, imposing serious concerns to environment and local agricultural industry. In searching for a potential solution to reduce or eliminate the waste, this research explored feasibility of producing a value -added product, sodium sulfate, from the waste and utilizing the product in textile dyeing. The results indicated that sodium sulfate could be produced from the salt and could be purified by a recrystalization method in a temperature range within the highest and lowest daily temperatures in summer in the alley. The recovered sodium sulfate samples, with purities ranging from 67% to 99.91, were compared with commercially available sodium sulfate in direct dyeing of cotton fabrics. The salt samples recovered from Mendata, California (〉98.8% sodium sulfate) cause little color difference in the dyeing with selected direct dyes, and the purified salt (Ⅲ) (99.91% sodium sulfate) is more applicable for direct dyeing of cotton fabrics if it has no other toxic effects. The recovered sodium sulfate from certain areas in the valley could not be employed in direct dyeing due to the high level of impurities in it.

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Salt and Pepper Noise Removal Considering Directionality of Local Mask (국부 마스크의 방향성을 고려한 Salt and Pepper 잡음 제거)

  • Hong, Sang-Woo;Kwon, Se-Ik;Kim, Nam-Ho
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2016.05a
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    • pp.676-678
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    • 2016
  • Noise occurs in the process of obtaining, transmission, and processing in image processing systems and these noises lower the resolution of image and cause visual errors. Currently, a representative filter to remove salt and pepper noise is SMF(standard median filter) but it is inadequate in preserving edge as the noise field expands. Therefore, for salt and pepper noise enviroment, the study suggested and algorithm that are places with original pixel when the central pixel is non-noise and process by applying weighted value on areas with less local mask pixel changes when there is noise.

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A Study on the Automatic Measurement of Salt Contamination (염분 오손 자동측정에 관한 연구)

  • Kwak, Hee-Ro;Kim, Han-Sang;Kweon, Dong-Jin;Lee, Dong-Zoon;Kim, Kyoung-Wha;Cho, Kug-Hee
    • Proceedings of the KIEE Conference
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    • 1995.07c
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    • pp.1362-1364
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    • 1995
  • In this paper, the automatic device for measuring the salt contamination on insulators was developed. The device consists of electronic insulators, measuring system, monitoring system, and printer. It was shown that the level of salt contamination measured by the developed device is similar to that measured by the brush cleaning method. Therefore, the developed automatic measuring device can be used in field, in order to predict the cleaning time of insulators and prevent the failure due to the salt contamination.

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Salt Injury and Overcoming Strategy of Rice (수도의 염해와 대책)

  • 이승택
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.34 no.s02
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    • pp.66-80
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    • 1989
  • Salt injury in rice is caused mainly by the salinity in soil and in the irrigated water, and occasionaly by salinity delivered through typhoon from the sea. The salt concentration of rice plants increased with higher salinity in the soil of the rice growing. The climatic conditions, high temperature and solar radiation and dry conditions promote the salt absorption of rice plant in saline soil. The higher salt accumulation in the rice plant generally reduces the root activity and inhibits the absorption of minerals of rice plant, resulting the reduction of photosynthesis. The salt damages of rice plant, however, are different from different growth stage of rice plants as follows: 1. Germination of rice seed was slightly delayed up to 1.0% of salt concentration and remarkably at 1. 5%, but none of rice seeds were germinated at 2.5%. This may be due to the delayed water uptake of rice seeds and the inhibition of enzyme activity, 2. It was enable to establish rice seedlings at seed bed by 0.2% of salt concentration with some reduction of leaf elongation. The increasing of 0.3% salt concentration caused to the seedling death with varietal differences, but most of seedlings were death at 0.4% with no varietal differences. 3. Seedlings grown at the nursery over 0.1% salt, gradually reduced in rooting activity after transplanting according to increasing the salt concentration from 0.1% up to 0.3% of paddy field. However, the seedlings grown in normal seed bed showed no difference in rooting between varieties up to 0.1% but significantly different at 0.3% between varieties, but greatly reduced at 0.5% and died at last in paddy after transplanting. 4. At panicle initiation stage, rice plant delayed in heading by salt damage, at meiotic stage reduced in grains and its filling rate due to inhibition of glume and pollen developing, and salt damage at heading stage and till 3 weeks after heading caused to reduction of fertilization and ripening rate. In viewpoint of agricultural policy the overcoming strategy for salt injury is to secure sufficient water source. Irrigation and drainage systems as well as underground drainage is necessary to desalinize more effectively. This must be the most effective and positive way except cost. By cultural practice, growing the salt tolerant variety with high population could increase yield. The intermittent irrigation and fresh water flooding especially at transplanting and from panicle initiation to heading stage, the most sensitive to salt injury, is important to reduce the salt content in saline soil. During the off-cropping season, plough and rotavation with flooding followed by drainage, or submersion and drainage with groove could improve the desalinization. Increase of nitrogen fertilizer with more split application, and soil improvement by lime, organic matter and forign soil addition, could increase the rice yield. Shift of trans-planting is one of the way to escape from the salt injury.

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Control of broadleaf weeds with 2,4-D in barley field (맥작에 있어서 2,4-D에 의한 광엽잡초 방제에 관한 연구)

  • Ryang H. S.;Jeon J. C.;Kim S. J.
    • Korean journal of applied entomology
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    • v.15 no.4 s.29
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    • pp.185-191
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    • 1976
  • This study was conducted to evaluate the performance of 2,4-D amine salt (2,4-dichlorophenoxy acetic acid) 40EC in broadleaf weeds control under diverse conditions of rate and time of application and soil type in fall barley field. The results obtained were summarized as follows: 1) At the rate of 70cc prod./10a, 2,4-D amine salt treated during the fully tillered stage of barley was effective for the control of most broadleaf weeds without crop injury. 2) The fully tillered stage was a optimun time lot the application of 2,4-D amine salt in fall barley. Earlier(zero-to four-leaf stage) or late. (boot stage to flowering) application than this stage caused a crop injury and resulted in yield reduction. 3) It was possible to safely use 2,4-D amine salt in fall barley regardless of soil types if applied the rate of 70cc prod./10a at the fully tillered stage.

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The Analysis of Chloride Penetration at Concrete and Repair Material under Tidal and Splash Zone (조간대와 비말대의 콘크리트와 보수재의 염분침투 특성분석)

  • Lee, Joon-Gu;Cho, Young-Kwoun;Kim, Meyong-Won;Kim, Kwan-Ho;Joo, Jae-Hong;Kim, Han-Joung
    • Proceedings of the Korea Concrete Institute Conference
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    • 2010.05a
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    • pp.207-208
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    • 2010
  • The building that supply tidal and splash zone was constructed near Seamangeum Gate Bridge. The specimens that will be tested for maintenance of gate bridge were exposed on the tidal and splash zone, totally about 650. The characteristics of strength, salt penetration profile, field application of surface repair material and section recover material will be acquired by periodical test. The program was developed to obtain optimal maintenance strategy of gate bridge as a marine concrete structure and to deposit experimental data, lab. test result, field test result, on its D/B. On this paper, the comparison of concrete and recover material in the salt penetration characteristics was expressed. The quantitative analysis of salt contents in concrete surface was most important so the improvement for the machine of gathering power of concrete and the apparatus of measuring chloride contents was proceeded at this time. The two conclusions were summarized like as - The resistance of chloride attack of concrete was appeared 2.5 times bigger than that of recover material - The resistance of chloride attack of polymer series was appeared more higher than that of others.

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Rice plants regenerated under saline conditions displayed salt tolerance and stress memory

  • Cho, Hyun Min;Chun, Hyun Jin;Kim, Min Chul
    • Proceedings of the Korean Society of Crop Science Conference
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    • 2017.06a
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    • pp.152-152
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    • 2017
  • Plants exposed to environmental stress for long durations often can adapt to stress conditions with improved tolerance. Moreover this acquired tolerance to stress can be retained even after reverting to destressed growth conditions, which is known to stress memory. In these adaptation and stress memory processes, epigenetic regulation, such as DNA methylation and histone modifications play a key role. Here, we showed that regenerated rice plants from embryogenic callus exposed to gradually increasing NaCl concentrations (up to 120 mM NaCl) acquired salt tolerance and their enhanced tolerance are inherited to subsequent generations. The rice plants (R0) regenerated from rice callus under saline conditions were transplanted into normal paddy field and R1 seeds were harvested. These R1 seeds displayed higher germination rate on MS medium containing 100mM NaCl than wild-type. The callus derived from R1 seeds showed better growth than control callus on high salinity medium. And the salt-adapted R1 plants exhibited higher chlorophyll contents and also higher $K^+/Na^+$ ratio than wild-type rice under saline conditions. The results indicated that rice plants successfully adapted to saline growth conditions during regeneration on high salt medium and moreover this acquired tolerance to salt stress was inherited subsequent generation.

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