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Calculation of Unit Hydrograph from Discharge Curve, Determination of Sluice Dimension and Tidal Computation for Determination of the Closure curve (단위유량도와 비수갑문 단면 및 방조제 축조곡선 결정을 위한 조속계산)

  • 최귀열
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.7 no.1
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    • pp.861-876
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    • 1965
  • During my stay in the Netherlands, I have studied the following, primarily in relation to the Mokpo Yong-san project which had been studied by the NEDECO for a feasibility report. 1. Unit hydrograph at Naju There are many ways to make unit hydrograph, but I want explain here to make unit hydrograph from the- actual run of curve at Naju. A discharge curve made from one rain storm depends on rainfall intensity per houre After finriing hydrograph every two hours, we will get two-hour unit hydrograph to devide each ordinate of the two-hour hydrograph by the rainfall intensity. I have used one storm from June 24 to June 26, 1963, recording a rainfall intensity of average 9. 4 mm per hour for 12 hours. If several rain gage stations had already been established in the catchment area. above Naju prior to this storm, I could have gathered accurate data on rainfall intensity throughout the catchment area. As it was, I used I the automatic rain gage record of the Mokpo I moteorological station to determine the rainfall lntensity. In order. to develop the unit ~Ydrograph at Naju, I subtracted the basic flow from the total runoff flow. I also tried to keed the difference between the calculated discharge amount and the measured discharge less than 1O~ The discharge period. of an unit graph depends on the length of the catchment area. 2. Determination of sluice dimension Acoording to principles of design presently used in our country, a one-day storm with a frequency of 20 years must be discharged in 8 hours. These design criteria are not adequate, and several dams have washed out in the past years. The design of the spillway and sluice dimensions must be based on the maximun peak discharge flowing into the reservoir to avoid crop and structure damages. The total flow into the reservoir is the summation of flow described by the Mokpo hydrograph, the basic flow from all the catchment areas and the rainfall on the reservoir area. To calculate the amount of water discharged through the sluiceCper half hour), the average head during that interval must be known. This can be calculated from the known water level outside the sluiceCdetermined by the tide) and from an estimated water level inside the reservoir at the end of each time interval. The total amount of water discharged through the sluice can be calculated from this average head, the time interval and the cross-sectional area of' the sluice. From the inflow into the .reservoir and the outflow through the sluice gates I calculated the change in the volume of water stored in the reservoir at half-hour intervals. From the stored volume of water and the known storage capacity of the reservoir, I was able to calculate the water level in the reservoir. The Calculated water level in the reservoir must be the same as the estimated water level. Mean stand tide will be adequate to use for determining the sluice dimension because spring tide is worse case and neap tide is best condition for the I result of the calculatio 3. Tidal computation for determination of the closure curve. During the construction of a dam, whether by building up of a succession of horizontael layers or by building in from both sides, the velocity of the water flowinii through the closing gapwill increase, because of the gradual decrease in the cross sectional area of the gap. 1 calculated the . velocities in the closing gap during flood and ebb for the first mentioned method of construction until the cross-sectional area has been reduced to about 25% of the original area, the change in tidal movement within the reservoir being negligible. Up to that point, the increase of the velocity is more or less hyperbolic. During the closing of the last 25 % of the gap, less water can flow out of the reservoir. This causes a rise of the mean water level of the reservoir. The difference in hydraulic head is then no longer negligible and must be taken into account. When, during the course of construction. the submerged weir become a free weir the critical flow occurs. The critical flow is that point, during either ebb or flood, at which the velocity reaches a maximum. When the dam is raised further. the velocity decreases because of the decrease\ulcorner in the height of the water above the weir. The calculation of the currents and velocities for a stage in the closure of the final gap is done in the following manner; Using an average tide with a neglible daily quantity, I estimated the water level on the pustream side of. the dam (inner water level). I determined the current through the gap for each hour by multiplying the storage area by the increment of the rise in water level. The velocity at a given moment can be determined from the calcalated current in m3/sec, and the cross-sectional area at that moment. At the same time from the difference between inner water level and tidal level (outer water level) the velocity can be calculated with the formula $h= \frac{V^2}{2g}$ and must be equal to the velocity detertnined from the current. If there is a difference in velocity, a new estimate of the inner water level must be made and entire procedure should be repeated. When the higher water level is equal to or more than 2/3 times the difference between the lower water level and the crest of the dam, we speak of a "free weir." The flow over the weir is then dependent upon the higher water level and not on the difference between high and low water levels. When the weir is "submerged", that is, the higher water level is less than 2/3 times the difference between the lower water and the crest of the dam, the difference between the high and low levels being decisive. The free weir normally occurs first during ebb, and is due to. the fact that mean level in the estuary is higher than the mean level of . the tide in building dams with barges the maximum velocity in the closing gap may not be more than 3m/sec. As the maximum velocities are higher than this limit we must use other construction methods in closing the gap. This can be done by dump-cars from each side or by using a cable way.e or by using a cable way.

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Development of a Ranging Inspection Technique in a Sodium-cooled Fast Reactor Using a Plate-type Ultrasonic Waveguide Sensor (판형 웨이브가이드 초음파 센서를 이용한 소듐냉각고속로 원격주사 검사기법 개발)

  • Kim, Hoe Woong;Kim, Sang Hwal;Han, Jae Won;Joo, Young Sang;Park, Chang Gyu;Kim, Jong Bum
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.25 no.1
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    • pp.48-57
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    • 2015
  • In a sodium-cooled fast reactor, which is a Generation-IV reactor, refueling is conducted by rotating, but not opening, the reactor head to prevent a reaction between the sodium, water and air. Therefore, an inspection technique that checks for the presence of any obstacles between the reactor core and the upper internal structure, which could disturb the rotation of the reactor head, is essential prior to the refueling of a sodium-cooled fast reactor. To this end, an ultrasound-based inspection technique should be employed because the opacity of the sodium prevents conventional optical inspection techniques from being applied to the monitoring of obstacles. In this study, a ranging inspection technique using a plate-type ultrasonic waveguide sensor was developed to monitor the presence of any obstacles between the reactor core and the upper internal structure in the opaque sodium. Because the waveguide sensor installs an ultrasonic transducer in a relatively cold region and transmits the ultrasonic waves into the hot radioactive liquid sodium through a long waveguide, it offers better reliability and is less susceptible to thermal or radiation damage. A 10 m horizontal beam waveguide sensor capable of radiating an ultrasonic wave horizontally was developed, and beam profile measurements and basic experiments were carried out to investigate the characteristics of the developed sensor. The beam width and propagation distance of the ultrasonic wave radiated from the sensor were assessed based on the experimental results. Finally, a feasibility test using cylindrical targets (corresponding to the shape of possible obstacles) was also conducted to evaluate the applicability of the developed ranging inspection technique to actual applications.

Role of Radiotherapy for Squamous Cell Carcinoma of the External Auditory Canal and Middle Ear (외이도 및 중이 편평상피암의 방사선치료)

  • Kang, Hyun-Cheol;Wu, Hong-Gyun;Lee, Ji-Hye;Park, Charn-Il;Kim, Chong-Sun;Oh, Seung-Ha;Heo, Dae-Seog;Kim, Dong-Wan;Lee, Se-Hoon
    • Radiation Oncology Journal
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    • v.27 no.4
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    • pp.173-180
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    • 2009
  • Purpose: To investigate the role of radiotherapy for squamous cell carcinomas of the external auditory canal and middle ear. Materials and Methods: A series of 35 patients who were treated at a single institution from 1981 through 2007 were retrospectively analyzed. Thirteen patients were treated by radiotherapy alone; four by surgery only and 18 by a combination of surgery and radiotherapy. The total radiation dose ranged from 39~70 Gy (median, 66 Gy) in 13~35 fractions for radiotherapy alone and 44~70 Gy (median, 61.2 Gy) in 22~37 fractions for the combined therapy. Clinical end-points were the cause of specific survival (CSS) and local relapse-free survival (LRFS). The median follow-up time was 2.8 years (range, 0.2~14.6 years). Results: The 3-year CSS and LRFS rate was 80% and 63%, respectively. Based on a univariate analysis, performance status and residual disease after treatment had a significant impact on CSS; performance status and histologic grade for LRFS. Patients treated by radiotherapy alone had more residual disease following the course of treatment compared to patients treated with the combined therapy; 69% vs. 28%, respectively. Conclusion: Our results suggest that radiation alone was not an inferior treatment modality for CSS compared to the combined therapy for squamous cell carcinoma of the external auditory canal and middle ear. However, local failure after radiotherapy is the main issue that will require further improvement to gain optimal local control.

Effects of Recombinant Human Epidermal Growth Factor (rhEGF) on Experimental Radiation-Induced Oral Mucositis in Rats (Rat의 방사선 조사성 구내염에 대한 Recombinant Human Epidermal Growth Factor (rhEGF)의 효과)

  • Jung Kwon-Il;Kim Sun-Hee;Moon Soo-Young;Kim Yeon-Wha;Hong Joon-Pio;Kim Hyun-Sook;Lee Sang-Wook
    • Radiation Oncology Journal
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    • v.24 no.1
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    • pp.67-76
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    • 2006
  • Purpose: Oral mucositis is a common toxicity of radiation or chemotherapy, which is used a treatment for head and neck cancer. We investigated effects of recombinant human epidermal growth factor (rhEGF) on radiation-induced oral mucositis in rat model. Materials and Methods: Spraque-Dawley rats (7 per group) exposed to a single dose of 25 Gy (day 0) on their head, except for one group, were randomly divided into un-treated, vehicle-treated, and two rhEGF-treated groups. Rats were topically applied with rhEGF (15 or $30{\mu}g/oral$ cavity/day) or vehicle to their oral mucosa. Survival rate of rats, weight changes, and food intakes were examined from day 0 to 18 after radiation. Histology study was performed from oral mucosa of rats at day 7 and 18 after radiation. Results: rhEGF-treated groups (15 or $30{\mu}g/oral$) showed all survival rate 33%, whereas un-treated and vehicle-treated groups showed all survival rate 0% at the end of experiment. rhEGF-treated groups statistically had less weight loss compared to vehicle-treated group from day 2 to 7 after radiation. Food intake of rats with rhEGF treatment turned to increase at day 14 after radiation. At 7 day after radiation, un-treated and vehicle-treated groups showed severe pseudomembraneous or ulcerative oral mucositis. On the other hand, rhEGF-treated groups had no more than cellular swelling and degeneration of epidermal cells in oral mucosa of rats. Conclusion: These results suggest that rhEGF has significantly positive effects on radiation-induced oral mucositis in rats. rhEGF display a therapeutic potential on a clinical level.

Reference Values of Functional Parameters in Gated Myocardial Perfusion SPECT : Comparison with $QGS^{\circledR}$ and $4DM^{\circledR}$ Program (게이트 심근 관류 스펙트의 심기능 지표의 정상 참고값 : $QGS^{\circledR}$ 프로그램과 $4DM^{\circledR}$ 프로그램의 비교)

  • Jeong, Young-Jin;Park, Tae-Ho;Cha, Kwang-Soo;Kim, Moo-Hyun;Kim, Young-Dae;Kang, Do-Young
    • The Korean Journal of Nuclear Medicine
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    • v.39 no.6
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    • pp.430-437
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    • 2005
  • Purpose: The objectives of this study were - First, to determine the normal range of left ventricular end diastolic volume (EDV), end systolic volume (ESV) and election fraction (EF) from gated myocardial perfusion SPECT for Quantitative Gated SPECT (QGS) and 4D-MSPECT (4DM), respectively. Second, to evaluate the relationships between values produced by both software packages. Materials & Methods: Tc-99m MIBI gated myocardial perfusion SPECT were performed for 77 patients (mean age: $49.6{\pm}13.7y$, n=37(M), 40(F)) with a low likelihood (<10%) of coronary artery disease (CAD) using dual head gamma camera (E.CAM, Siemens, USA). Left ventricular EDV, ESV and EF were automatically measured by means of QGS and 4DM, respectively. Results: in QGS, the mean EDV, ESV and EF for all patients were $78.2{\pm}25.2ml,\;27.4{\pm}12.9ml\;and\;66.6{\pm}8.0%$ at stress test respectively, not different from rest test (p>0.05). In 4DM, the mean EDV, ESV and EF for all patients were $89.1{\pm}26.4ml,\;29.1{\pm}12.8ml\;and\;68.5{\pm}6.7%$ at stress test. Most cases in 4DM, there was no significant difference statistically between stress and rest test (p>0.05). But statistically significant difference was found in EF ($68.5{\pm}6.7%$ at stress vs $70.9{\pm}8.0%$ at rest, p<0.05). Correlation coefficients between the methods for EDV, ESV and EF were comparatively high (0.95, 0.93, 0.71 at stress test and 0.95, 0.90, 0.69 at rest test, respectively). However, Bland-Altman plots showed a large range of the limit value of agreement for EDV, ESV and EF between both methods ($-30ml{\sim}10ml,\;-12ml{\sim}8ml,\;-14%{\sim}11%$ at stress test and $-32ml{\sim}5ml,\;-13ml{\sim}13ml,\;-18%{\sim}12%$ at rest test). Conclusion: We found the normal ranges of EDV, ESV and EF for patients with a low likelihood of CAD in both methods. We expect these values will be a good reference to interpret gated myocardial perfusion SPECT. Although good correlation was observed between both methods, they should not be used interchangeably. Therefore, when both programs are used at the same site, it will be important to apply normal limits specific to each method.

The Vogue about Outwearization of Underwear in a Tendency to the Century-end (세기말 현상으로 본 속옷의 겉옷화 현상)

  • 이상례
    • Journal of the Korean Society of Costume
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    • v.35
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    • pp.325-341
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    • 1997
  • One of the noticeable trends of female wear in 1990s is the Outwearization of Underwear as it is called 'Lingerie look' This trend meaned 'Exposure Fashion' raised splendidly its head to the whole stage of fashion destrying the tradional concept having divided the fashion between outwear and underwear by Madonna an Americal populer singer showed up in front of the audience wearing the corset-dress as a stage custome. This corset-dress which can not be recognised whether it is underwear or outwear has been diffused into the mass as a fashionable trend re-gardless of any reason; therefore discrimi-nation of wear by space by far that is underwear should have the sstandard telling between private and public sector has been gradually tumbled. By the way what has propelled desigers to introduce the style continuously having the underwear motive such as outwear almost as same as underwear or underwear worn on out-wear etc. and has made it a fashion trends? How do we accept this "Ligerie look'fashion" The rearch on vogue of outwearization of underwear started by the questions above can be summarized as the followings The division between the sprit and the ma-terial-economic shrinkage by the collapse of the bubble economy in the late of 20 century and expectation for the next century doubt by changes of international politics dynamics for the next century and increasement of psycho-logical tention by the environmental destruc-tion etc, has been extended to break the sense of value down These frustration of the tra-ditional values and dissatisfaction on the pres-ent have reflected on the fashion pursuing some more sensational style to increase the ex-posure of the body. The revolution of wearing bouncing the con-servatismhas outwardly expressed underwear of the private sector. Therefore the spatial concept of wear which for the public sec-tor has been fallen into pieces and has broken the wall of the concept fixed by outwear on underwear. in addition the stage costome for the popular people like Madonna has not been limited by the specularity any more and has been assimilated with the normal wear on the street to take the distinction for away. The circumstances of the late of 20 century pursuing sensation and making sex commer-cialized have accordance with the outweari-zation of underwear. there it is on the basis of Minimalist's dogmatism has been expressed the maximization of expoure in the pubric space to popularize bra pants(knickers) as outwear. The reaction on the attribute of hiding and shanding has brought 'See-Through fashion' with the transparent materials, The contemporary doubt recalling the mem-ory of the past has sublimated corset which was an instument of toture for women into Romanticism to introduce it to fashion with the development of a new material not to be a tool of any oppression and maltretment any longer. The popularization of outwear like underwear what's more has brought high quality of underwear. There it has called for the variety of materials such as knit demin and velvet etc, and has urged the famous designers to enlarge their working boundaries to underwear designs, Besides outwearization of underwear has been popular even in the Orient which has the con-servative opinions on exposure ; so changes of the thoughts can be seen among the establish-ment generation on exposure of the body. As the more high tech information publi-cized and the more technology and media digitalized the more expression being analog the pursue for the new in fashion with vision never been seen and even though it is imprac-tical the experimental designers have drived the freedom beyond the traditional roles of the previous century. Consequently outwearization of underwear may be viewd as a trial as an expression responded the contemporary background. This trend in my opinion will have been lasted for a while by being proliperlated among lasted for a while by being proliperlated among the pub-lic who has the century-end anxiety and doubt and expectation for the next century.

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Development and Effectiveness of the Primary Hospice Education Program for Nurses (간호사를 위한 호스피스 기초 교육 프로그램 및 효과)

  • In, Sook-Jin
    • 한국호스피스완화의료학회:학술대회논문집
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    • 2004.07a
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    • pp.100-102
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    • 2004
  • Under the current medical system, a terminal patient and his/her family who are neglected inevitably face various aspects of crises including not only physical, but also psychological, social, economic, spiritual and legal problems. Nurses often look after many terminal patents with these types of complicated problems. Therefore, educating the nurses who will take care of such patents would greatly reduce stress so the patents end could their lives in peace and without losing their dignity. This research is a quasi experimental study of nonequivalent control group. A pretest-posttest design where a basic education program is developed for nurses, who frequently treat terminal patents, to understand the importance of the role of hospice and to apply their understandings to treat terminal lancer patents. A sample of the nurses were taken from those who were working in general wards at two general hospitals in Seoul during October, 2003${\sim}$December 2003. The study was composed of 46 experimental group and 43 control group. A basic hospice education program was developed by taking emphasized and overlapping parts from advanced practice hospice nurses education course, short-term education course, an extensive literature survey and by consulting three professionals as well. With the group of 5 professors with vast experiences in oncolgy, 5 nursing administrator, 3 nursing practitioner, the tentative first version of the program was developed and reviewed. Afterwards, by utilizing person to person interviews with 2 head nurses experienced with terminal patients, 1 nurse in charge of hospice, 1 nurse on the contents of the program, and a person to person rating on the educating medium by a nurse were performed. The final version of a basic education program was developed after the second revision. The hospice basic education program consists of introduction to hospice, hospice and commucation, management of pain for terminal cancer patients, physical management for terminal cancer patients, socio-psycological caring of terminal cancer patients and management of death and separation. Total education time was four hours organized into 50 minutes of instruction and 10 minutes of break. $Powerpoint^{(R)}$ software was used as the education medium. As research tools, "Knowledge on Hospice" was developed by the author after receiving a review from one expert. "Attitude of Hospice Nursing" was revised Kim(2001)'s attitude measuring tool which was based on Wang(1998), Kwon(1989), Park and Sung(1991)'s tool. "Liability on nursing terminal patients" was used as developed by Zarits(1980) and Mongomory(1985) translated by Lee(1985). For collecting data, preliminary investigation prior to 1 week of the hospice basic education program and post-investigations after 1 week and 4 weeks of the education were carried out for the nurses at a general ward who understood and agreed on the purpose of the program. Collected data were analyzed throughout t-test, $x^2-test$, Manova test and Bonferroni correction in $SAS^{(R)}$ program. The summary of the investigation is as follows: Hypothesis 1: "Educated experimental group would possess more knowledge on hospice compared to the un-educated control group" was supported after 1 (F=12.14, p=.00) and 4 (F=5.3, p=.02) weeks of education. Hypothesis 2: "Educated experimental group would take a positive attitude toward hospice nursing compared to the un-educated control group" was supported after 1(F=3.92, p=.05) and 4(F=5.05, p=.02) weeks of education. Hypothesis 3: "Educated experimental poop would feel less liability compared to the un-educated control group in nursing terminal cancer patients' was rejected. In this study, it was found that knowledge on hospice was significantly important. By applying hospice basic education programs to nurses, the education program helped nurses to take a positive attitude toward terminal patients. It was, however, seen that the education program had no effect on alleviating liability in nursing terminal patients. Therefore, it is expected that this educational program would help hospices and nurses at general wards to understand the concept and the role of hospice so that terminal patents, now neglected under current medical system, would be able to end their lives in peace.

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The Distributional Patterns of Silla Burial Grounds and the Character of Outer Coffin Tombs in Jjoksaem Site, Gyeongju (쪽샘유적 신라고분 분포양상과 목곽묘의 성격)

  • Yun, Hyoung-Jun
    • Korean Journal of Heritage: History & Science
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    • v.50 no.4
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    • pp.198-221
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    • 2017
  • The Jjoksaem site is the eastern sector of Daereungwon Ancient Tomb Complex, Gyeongju(the 512th Historic site) called Wolseong North Burial Ground in academic community. The excavation and research of this site was conducted from 2007 to 2015, with the purpose of basic data offering for the restoration of Silla tumuli and development of ancient tomb park. As a result of the investigation, more than 700 new tombs were discovered except the 155 tumuli founded in the Japanese colonial era. Moreover, more than 70 percent of the smaller tombs, such as outer coffin tombs, were discovered here. There are four characteristics of outer coffin tombs in Jjoksaem site. First, it is recognized the Gyeongju-styled outer coffin tombs have a long rectangular shape, distinct from Gimhae-styled outer coffin tombs in a rectangular shape. Second, they are divided into three groups by the size of the grave area. This is indirectly related to the rank and the status of the buried person. Third, these tombs began to be constructed at the end of the 3rd century before the time of wooden chamber tombs covered by stone and earthen mound. They were ruined because of the new tombs constructed at the period of Maripgan. This reflects that the identity of the former tombs was not respected by the communities in the later generations. Outer coffin tombs were consistently made to the end of the era of wooden chamber tombs covered by stone and earthen mound. Lastly, the area of burial ground of outer coffin tombs is limited by wooden chamber tombs covered by stone and wooden mounds. Otherwise, the location of the burial ground for the deceased is limited by the status of the deceased. The idea that wooden chamber tombs covered by stone and earthen mound are located on the above ground turns out to be incorrect. In Jjoksaem site, there is little difference between the height of the circular burial protection stone and the height of the digging lines of the other tombs. In the case of No.44 tumulus, the lowest step of the circular burial protection stones is lower than those of the other tombs and tumuli. Research of outer coffin tombs at Jjoksaem site will be to suggest important academic data about the changing period from Saroguk, as the head of chiefdom union, to Silla, as state.

Development of Eggs, Larvae and Juveniles of the Ladislavia taczanowskii from Hongcheongang-River (홍천강에 서식하는 멸종위기종 새미 Ladislavia taczanowskii의 난발생 및 자치어 형태발달)

  • Jae-Min Park;Seong-Jang Cho;Kyeong-Ho Han
    • Korean Journal of Ichthyology
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    • v.36 no.2
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    • pp.109-119
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    • 2024
  • This study was conducted to investigate the early life history by observing the egg development of Ladislavia taczanowskii in endangered fish and to use it as basic data for species conservation research. The broodstork used in the study was secured from the area of the Hongcheon River in Hongcheon-gun, Gangwon State. The broodstork, who was being raised in the laboratory, selected mature individuals in May 2021 and induced them to spawn by hormone injection. The size of the maturation egg was 1.50~1.79 (average 1.59±0.08, n=30) mm due to the circular invasive egg. The incubation time took 168 hours at 16.5℃ and 109 hours and 30 minutes at 25.5℃. Newly hatched larvae, the consonants had a total length of 5.55~6.31 mm (6.30±6.93, n=30) mm, and the mouth and anus did not open and had egg yolk. 5 days after hatching, the preflexion larvae had a total length of 9.91~10.8 (10.1±0.27, n=30) mm, and the mouth and anus opened, and feeding activities began. 8 days after hatching, the flexion larvae had a total length of 10.3~11.4 (10.8±0.38, n=30) mm, and the end of the vertebrae at the tail fin tip began to bend upward. 10 day after hatching, the postflexion larvae had a total length of 11.8~13.1 (12.3±0.43, n=30) mm, and the end of the vertebrae at the tail tip was completely bent at 45°. 18 days after hatching, the total length of the juveniles was 18.9~23.4 (20.4±1.69, n=30) mm, and the number of fins in each part was fin rays with 10 dorsal fins, 9 anal fins, 22 caudal fins, and 7 ventral fins. As a result of the study, the postflexion larvae showed differences in morphology from other Gobioninae fishes in the upper part of the tail's hypural, the shape of spots on the dorsal vertebrae, the vertical stripes developed on the head, and the irregularly deposited melanophore throughout the body.

Wind and Flooding Damages of Rice Plants in Korea (한국의 도작과 풍수해)

  • 강양순
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.34 no.s02
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    • pp.45-65
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    • 1989
  • The Korean peninsular having the complexity of the photography and variability of climate is located within passing area of a lots of typhoon occurring from the southern islands of Philippines. So, there are various patterns of wind and flooding damages in paddy field occuring by the strong wind and the heavy rain concentrated during the summer season of rice growing period in Korea. The wind damages to rice plants in Korea were mainly caused by saline wind, dry wind and strong wind when typhoon occurred. The saline wind damage having symptom of white head or dried leaves occurred by 1.1 to 17.2 mg of salt per dry weight stuck on the plant which was located at 2. 5km away from seashore of southern coastal area during the period(from 27th to 29th, August, 1986) of typhoon &Vera& accompanying 62-96% of relative humidity, more than 6 m per second of wind velocity and 22.5 to 26.4$^{\circ}C$ of air temperature without rain. Most of the typhoons accompanying 4.0 to 8. 5m per second of wind and low humidity (lesp an 60%) with high temperature in the east coastal area and southen area of Korea. were changed to dry and hot wind by the foehn phenomenon. The dry wind damages with the symptom of the white head or the discolored brownish grain occurred at the rice heading stage. The strong wind caused the severe damages such as the broken leaves, cut-leaves and dried leaves before heading stage, lodging and shattering of grain at ripening stage mechanically during typhoon. To reduce the wind damages to rice plant, cultivation of resistant varieties to wind damages such as Sangpoongbyeo and Cheongcheongbyeo and the escape of heading stage during period of typhoon by accelerating of heading within 15th, August are effective. Though the flood disasters to rice plant such as earring away of field, burying of field, submerging and lodging damage are getting low by the construction of dam for multiple purpose and river bank, they are occasionally occurred by the regional heavy rain and water filled out in bank around the river. Paddy field were submerged for 2 to 4 days when typhoon and heavy rain occurred about the end of August. At this time, the rice plants that was in younger growing stage in the late transplanting field of southern area of Korea had the severe damages. Although panicles of rice plant which was in the meiotic growing stage and heading stage were died when flooded, they had 66% of yield compensating ability by the upper tilling panicle produced from tiller with dead panicle in ordinary transplanting paddy field. It is effective for reduction of flooding damages to cultivate the resistant variety to flooding having the resistance to bacterial leaf blight, lodging and small brown planthopper simultaneously. Especially, Tongil type rice varieties are relatively resistant to flooding, compared to Japonica rice varieties. Tongil type rice varieties had high survivals, low elongation ability of leaf sheath and blade, high recovering ability by the high root activity and photosynthesis and high yield compensating ability by the upper tillering panicle when flooded. To minimize the flooding and wind damage to rice plants in future, following research have to be carried out; 1. Data analysis by telemetering and computerization of climate, actual conditions and growing diagnosis of crops damaged by disasters. 2. Development of tolerant varieties to poor natural conditions related to flooding and wind damages. 3. Improvement of the reasonable cropping system by introduction of other crops compensating the loss of the damaged rice. 4. Increament of utilization of rice plant which was damaged.

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