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검색결과 4,815건 처리시간 0.032초

PET/CT 검사에서 주입선량의 변화에 따른 적정한 영상획득시간의 평가 (Evaluation of Proper Image Acquisition Time by Change of Infusion dose in PET/CT)

  • 김창현;이현국;송치옥;이기흔
    • 핵의학기술
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    • 제18권2호
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    • pp.22-27
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    • 2014
  • PET/CT검사는 장비의 발전과 더불어 환자의 피폭을 줄이기 위하여 저 선량을 사용하는 추세에 있다. 이에 PET/CT scanner의 영상의 질을 유지하기 위하여 주입선량의 변화에 따른 적정한 bed당 획득시간을 평가하고자 한다. 모형 실험은 NEMA NU2-1994 phantom으로 hot cylinder의 농도를 3, 4.3, 5.5, 6.7 MBq/kg 으로 증가시키고 bed당 획득시간을 30 sec, 1 min, 1 min 30 sec, 2 min, 2 min 30 sec, 3 min, 3 min 30 sec, 4 min, 4 min 30sec, 5 min, 5 min 30 sec 10 min, 20 min, 30 min로 늘려가며 영상을 획득 후 hot cylinder의 농도와 배후 방사능에 4개의 ROI (Region of Interest)을 설정하고 hot cylinder의 농도 와 bed당 획득시간에 따른 변화를 최대 표준섭취계수(Standard Uptake Value maximum, $SUV_{max}$)를 측정 후 신호 대 잡음비(Signal to Noise Ratio, SNR), BKG (Background)의 표준편차를 계산하여 비교해 보았다. 또한 4.3 MBq phantom을 이용하여 검사 대기시간의 변화(15분과 1시간)에 따른 각각의 $SUV_{max}$, SNR, BKG의 표준편차를 비교하였다. 단위 질량당 방사능의 농도가 3, 4.3, 5.5, 6.7 MBq으로 증가하고 또한 각 농도의 time/bed을 1분30초에서 30분까지 늘렸을 때 hot cylinder의 $SUV_{max}$ 값은 bed당 획득시간이 각 방사능의 농도에 따라 30초에서 2분까지는 최대 18.3에서 최소 7.3까지 변화가 심했고 2분 30초에서 30분까지는 최대 8에서 최소 5.6으로 일정한 $SUV_{max}$ 값을 나타내었다. 단위 질량당 방사능의 변화에 따른 SNR은 3 MBq에서는 최소 0.41에서 최대 0.49까지 일정하였고 4.3 MBq과 5.5 MBq에서는 각각 최소 0.23, 0.39에서 최대 0.59, 0.54로 bed당 획득시간이 늘수록 상승하였다. 방사능 농도 6.7 MBq에서는 30초에서 최대 0.59로 높았지만 이후 0.43에서 0.53으로 일정하게 유지하였다. BKG (Background)의 표준편차는 3 MBq에서 2분 30초 후부터 0.38에서 0.06으로 낮아졌고 4.3 MBq과 5.5 MBq에서는 1분 30초 후부터 0.38에서 0으로 낮아졌고 6.7 MBq에서는 30초에서 30분 전 구간에서 낮은 0.33에서 0.05이었다. 4.3 MBq 팬텀으로 검사대기시간을 15분과 1시간으로 변화시킨 결과에서는 bed당 획득시간이 2분 30초부터 $SUV_{max}$값이 서로 일정한 값을 보였고 SNR은 1분 30초부터 비슷한 값을 보였다. 위 결과와 같이 단위 질량당 주입된 방사능의 농도를 3, 4.3, 5.5, 6.7 MBq으로 증가시켰을 때 bed당 획득시간이 2분 30초 이상에서는 $SUV_{max}$와 SNR의 값이 서로 일정하게 유지되고 검사 대기시간의 변화(15분과 1시간)에서도 bed당 획득시간이 2분 30초 이상에서는 $SUV_{max}$와 SNR의 값이 일정하게 유지되는 것을 알 수 있었다. 이 NEMA NU2-1994 phantom 실험의 결과에서 주입되는 방사능의 농도의 변화에도 일정한 $SUV_{max}$와 SNR의 값을 구하기 위한 최소 bed당 획득시간은 2분 30초이라는 것을 알 수 있었다. 하지만 이 획득시간은 장비의 사양과 특성에 따라 차이가 있을 수 있다.

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지하수 관개에 의한 수도의 멸준양상과 그 방지책에 관한 연구 (Studies on the Rice Yield Decreased by Ground Water Irrigation and Its Preventive Methods)

  • 한욱동
    • 한국농공학회지
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    • 제16권1호
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    • pp.3225-3262
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    • 1974
  • The purposes of this thesis are to clarify experimentally the variation of ground water temperature in tube wells during the irrigation period of paddy rice, and the effect of ground water irrigation on the growth, grain yield and yield components of the rice plant, and, furthermore, when and why the plant is most liable to be damaged by ground water, and also to find out the effective ground water irrigation methods. The results obtained in this experiment are as follows; 1. The temperature of ground water in tube wells varies according to the location, year, and the depth of the well. The average temperatures of ground water in a tubewells, 6.3m, 8.0m deep are $14.5^{\circ}C$ and $13.1^{\circ}C$, respercively, during the irrigation period of paddy rice (From the middle of June to the end of September). In the former the temperature rises continuously from $12.3^{\circ}C$ to 16.4$^{\circ}C$ and in the latter from $12.4^{\circ}C$ to $13.8^{\circ}C$ during the same period. These temperatures are approximately the same value as the estimated temperatures. The temperature difference between the ground water and the surface water is approximately $11^{\circ}C$. 2. The results obtained from the analysis of the water quality of the "Seoho" reservoir and that of water from the tube well show that the pH values of the ground water and the surface water are 6.35 and 6.00, respectively, and inorganic components such as N, PO4, Na, Cl, SiO2 and Ca are contained more in the ground water than in the surface water while K, SO4, Fe and Mg are contained less in the ground water. 3. The response of growth, yield and yield components of paddy rice to ground water irrigation are as follows; (l) Using ground water irrigation during the watered rice nursery period(seeding date: 30 April, 1970), the chracteristics of a young rice plant, such as plant height, number of leaves, and number of tillers are inferior to those of young rice plants irrigated with surface water during the same period. (2) In cases where ground water and surface water are supplied separately by the gravity flow method, it is found that ground water irrigation to the rice plant delays the stage at which there is a maximum increase in the number of tillers by 6 days. (3) At the tillering stage of rice plant just after transplanting, the effect of ground water irrigation on the increase in the number of tillers is better, compared with the method of supplying surface water throughout the whole irrigation period. Conversely, the number of tillers is decreased by ground water irrigation at the reproductive stage. Plant height is extremely restrained by ground water irrigation. (4) Heading date is clearly delayed by the ground water irrigation when it is practised during the growth stages or at the reproductive stage only. (5) The heading date of rice plants is slightly delayed by irrigation with the gravity flow method as compared with the standing water method. (6) The response of yield and of yield components of rice to ground water irrigation are as follows: \circled1 When ground water irrigation is practised during the growth stages and the reproductive stage, the culm length of the rice plant is reduced by 11 percent and 8 percent, respectively, when compared with the surface water irrigation used throughout all the growth stages. \circled2 Panicle length is found to be the longest on the test plot in which ground water irrigation is practised at the tillering stage. A similar tendency as that seen in the culm length is observed on other test plots. \circled3 The number of panicles is found to be the least on the plot in which ground water irrigation is practised by the gravity flow method throughout all the growth stages of the rice plant. No significant difference is found between the other plots. \circled4 The number of spikelets per panicle at the various stages of rice growth at which_ surface or ground water is supplied by gravity flow method are as follows; surface water at all growth stages‥‥‥‥‥ 98.5. Ground water at all growth stages‥‥‥‥‥‥62.2 Ground water at the tillering stage‥‥‥‥‥ 82.6. Ground water at the reproductive stage ‥‥‥‥‥ 74.1. \circled5 Ripening percentage is about 70 percent on the test plot in which ground water irrigation is practised during all the growth stages and at the tillering stage only. However, when ground water irrigation is practised, at the reproductive stage, the ripening percentage is reduced to 50 percent. This means that 20 percent reduction in the ripening percentage by using ground water irrigation at the reproductive stage. \circled6 The weight of 1,000 kernels is found to show a similar tendency as in the case of ripening percentage i. e. the ground water irrigation during all the growth stages and at the reproductive stage results in a decreased weight of the 1,000 kernels. \circled7 The yield of brown rice from the various treatments are as follows; Gravity flow; Surface water at all growth stages‥‥‥‥‥‥514kg/10a. Ground water at all growth stages‥‥‥‥‥‥428kg/10a. Ground water at the reproductive stage‥‥‥‥‥‥430kg/10a. Standing water; Surface water at all growh stages‥‥‥‥‥‥556kg/10a. Ground water at all growth stages‥‥‥‥‥‥441kg/10a. Ground water at the reproductive stage‥‥‥‥‥‥450kg/10a. The above figures show that ground water irrigation by the gravity flow and by the standing water method during all the growth stages resulted in an 18 percent and a 21 percent decrease in the yield of brown rice, respectively, when compared with surface water irrigation. Also ground water irrigation by gravity flow and by standing water resulted in respective decreases in yield of 16 percent and 19 percent, compared with the surface irrigation method. 4. Results obtained from the experiments on the improvement of ground water irrigation efficiency to paddy rice are as follows; (1) When the standing water irrigation with surface water is practised, the daily average water temperature in a paddy field is 25.2$^{\circ}C$, but, when the gravity flow method is practised with the same irrigation water, the daily average water temperature is 24.5$^{\circ}C$. This means that the former is 0.7$^{\circ}C$ higher than the latter. On the other hand, when ground water is used, the daily water temperatures in a paddy field are respectively 21.$0^{\circ}C$ and 19.3$^{\circ}C$ by practising standing water and the gravity flow method. It can be seen that the former is approximately 1.$0^{\circ}C$ higher than the latter. (2) When the non-water-logged cultivation is practised, the yield of brown rice is 516.3kg/10a, while the yield of brown rice from ground water irrigation plot throughout the whole irrigation period and surface water irrigation plot are 446.3kg/10a and 556.4kg/10a, respectivelely. This means that there is no significant difference in yields between surface water irrigation practice and non-water-logged cultivation, and also means that non-water-logged cultivation results in a 12.6 percent increase in yield compared with the yield from the ground water irrigation plot. (3) The black and white coloring on the inside surface of the water warming ponds has no substantial effect on the temperature of the water. The average daily water temperatures of the various water warming ponds, having different depths, are expressed as Y=aX+b, while the daily average water temperatures at various depths in a water warming pond are expressed as Y=a(b)x (where Y: the daily average water temperature, a,b: constants depending on the type of water warming pond, X; water depth). As the depth of water warning pond is increased, the diurnal difference of the highest and the lowest water temperature is decreased, and also, the time at which the highest water temperature occurs, is delayed. (4) The degree of warming by using a polyethylene tube, 100m in length and 10cm in diameter, is 4~9$^{\circ}C$. Heat exchange rate of a polyethylene tube is 1.5 times higher than that or a water warming channel. The following equation expresses the water warming mechanism of a polyethylene tube where distance from the tube inlet, time in day and several climatic factors are given: {{{{ theta omega (dwt)= { a}_{0 } (1-e- { x} over { PHI v })+ { 2} atop { SUM from { { n}=1} { { a}_{n } } over { SQRT { 1+ {( n omega PHI) }^{2 } } } } LEFT { sin(n omega t+ { b}_{n }+ { tan}^{-1 }n omega PHI )-e- { x} over { PHI v }sin(n omega LEFT ( t- { x} over {v } RIGHT ) + { b}_{n }+ { tan}^{-1 }n omega PHI ) RIGHT } +e- { x} over { PHI v } theta i}}}}{{{{ { theta }_{$\infty$ }(t)= { { alpha theta }_{a }+ { theta }_{ w'} +(S- { B}_{s } ) { U}_{w } } over { beta } , PHI = { { cpDU}_{ omega } } over {4 beta } }}}} where $\theta$$\omega$; discharged water temperature($^{\circ}C$) $\theta$a; air temperature ($^{\circ}C$) $\theta$$\omega$';ponded water temperature($^{\circ}C$) s ; net solar radiation(ly/min) t ; time(tadian) x; tube length(cm) D; diameter(cm) ao,an,bn;constants determined from $\theta$$\omega$(t) varitation. cp; heat capacity of water(cal/$^{\circ}C$ ㎥) U,Ua; overall heat transfer coefficient(cal/$^{\circ}C$ $\textrm{cm}^2$ min-1) $\omega$;1 velocity of water in a polyethylene tube(cm/min) Bs ; heat exchange rate between water and soil(ly/min)

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소나무 천연집단(天然集團)의 변이(變異)에 관(關)한 연구(硏究)(III) -주왕산(周王山), 안면도(安眠島), 오대산(五臺山) 소나무집단(集團)의 차대(次代)의 유전변이(遺傳變異)- (The Variation of Natural Population of Pinus densiflora S. et Z. in Korea (III) -Genetic Variation of the Progeny Originated from Mt. Chu-wang, An-Myon Island and Mt. O-Dae Populations-)

  • 임경빈;권기원
    • 한국산림과학회지
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    • 제32권1호
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    • pp.36-63
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    • 1976
  • 1974년(年) 천연(天然)소나무집단(集團)에 대한 유전적변이(遺傳的變異)를 분석(分析)하고져 먼저 경북(慶北) 청송군(靑松郡) 소재(所在) 주왕산(周王山)소나무림(林), 충남(忠南) 서산군(瑞山郡) 소재(所在) 안면도(安眠島) 소나무림(林), 그리고 강원도(江原道) 평창군(平昌郡) 소재(所在) 소나무림(林)을 대상(對象)으로하여 각(各) 집단(集團)에서 되도록 소면적(小面積)의 범위내(範圍內)에 서있는 소나무 개체(個體)를 각(各) 20주(株)씩 총 60주(株)를 택(擇)하여 그 모수(母樹)에 대한 형태학적(形態學的) 특성(特性)등을 조사측정(調査測定)하고 집단간(集團間)에 보이는 차이(差異) 그리고 한 집단내(集團內)에 있는 각개체수목(各個體樹木)의 형질(形質)을 조사보고(調査報告)한바 있다(제일보고문(第一報論文). 1974년(年) 가을에 가계별(家系別)로 종자(種字)을 채취(採取)하여서 가계별(家系別) 및 산지별(産地別)의 차이(差異)를 분석(分析)하고 동시(同時)에 그 종자(種字)를 파종하여서 1-0묘(苗) 및 1-1묘(苗)를 대상(對象)으로 생장인자(生長因子)에 대한 측정(測定)을 하고 그 유전력(遺傳力)을 계산(計算)해 보았다. 그밖에 엽록소함량(葉綠素含量) 또는 monoterpene등의 함량(含量)의 차이(差異)를 분석(分析)해 보았다. 종자(種字)의 형태학적(形態學的) 특성(特性)에 있어서는 집단간(集團間) 또 가계간(家系間)에 유의차(有意差)를 보이지 않는 것도 있었으나 대체(大體)로 유의차(有意差)가 인정(認定)되었다. 그리고 각형질간(各形質間)의 상관(相關)을 보았는데 구과폭(毬果幅)과 종자익(種字翼)의 폭(幅), 구과장(毬果長)과 종자익(種字翼)의 길이간(間), 그리고 구과(毬果) 생중량(生重量)과 종자중량간(種字重量間)에는 정(正)의 상관(相關)이 보였다. 묘고(苗高)와 근원경(根元徑)의 성장(成長)에 있어서는 가계간(家系間) 그리고 집단간(集團間)에 차이(差異)가 인정되었다. 묘고(苗高)의 유전력(遺傳力)은 집단(集團)의 평균치(平均値)를 가지고 분석(分析)하였다. 즉 집단(集團)에 관계(關係)되는 분산(分散)을 유전분산(遺傳分散)으로 보고서 유전력(遺傳力)을 계산(計算)해 보았는데 1-0묘(苗)의 묘고(苗高)에서는 0.29, 1-1묘(苗)에서는 0.14가 그리고 근원경(根元徑)에 있어서는 1-0묘(苗)는 0.15, 1-1묘(苗)에서는 0.06이였다. 기공열수(氣孔列數)에 있어서는 집단간차이(集團間差異)가 있었으나 거치밀도(鋸齒密度)에는 차이(差異)가 없었다. 침엽(針葉)의 특성(特性)에 관(關)해서는 모수(母樹)와 차대간(次代間)에 상관(相關)이 없었다. 엽록소함량(葉綠素含量)은 집단간차이(集團間差異)는 보였으나 가계간차이(家系間差異)는 없었다. monoterpene의 성분(成分)에 있어서는 myrcene과 ${\beta}$-phellandrene의 함량(含量)으로 집단차(集團差)를 볼 수 있었다.

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한국전쟁의 교훈과 대비 -병력수(兵力數) 및 부대수(部隊數)를 중심으로- (The lesson From Korean War)

  • 윤일영
    • 안보군사학연구
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    • 통권8호
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    • pp.49-168
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    • 2010
  • Just before the Korean War, the total number of the North Korean troops was 198,380, while that of the ROK(Republic of Korea) army troops 105,752. That is, the total number of the ROK army troops at that time was 53.3% of the total number of the North Korean army. As of December 2008, the total number of the North Korean troops is estimated to be 1,190,000, while that of the ROK troops is 655,000, so the ROK army maintains 55.04% of the total number of the North Korean troops. If the ROK army continues to reduce its troops according to [Military Reform Plan 2020], the total number of its troops will be 517,000 m 2020. If North Korea maintains the current status(l,190,000 troops), the number of the ROK troops will be 43.4% of the North Korean army. In terms of units, just before the Korean War, the number of the ROK army divisions and regiments was 80% and 44.8% of North Korean army. As of December 2008, North Korea maintains 86 divisions and 69 regiments. Compared to the North Korean army, the ROK army maintains 46 Divisions (53.4% of North Korean army) and 15 regiments (21.3% of North Korean army). If the ROK army continue to reduce the military units according to [Military Reform Plan 2020], the number of ROK army divisions will be 28(13 Active Division, 4 Mobilization Divisions and 11 Local Reserve Divisions), while that of the North Korean army will be 86 in 2020. In that case, the number of divisions of the ROK army will be 32.5% of North Korean army. During the Korean war, North Korea suddenly invaded the Republic of Korea and occupied its capital 3 days after the war began. At that time, the ROK army maintained 80% of army divisions, compared to the North Korean army. The lesson to be learned from this is that, if the ROK army is forced to disperse its divisions because of the simultaneous invasion of North Korea and attack of guerrillas in home front areas, the Republic of Korea can be in a serious military danger, even though it maintains 80% of military divisions of North Korea. If the ROK army promotes the plans in [Military Reform Plan 2020], the number of military units of the ROK army will be 32.5% of that of the North Korean army. This ratio is 2.4 times lower than that of the time when the Korean war began, and in this case, 90% of total military power should be placed in the DMZ area. If 90% of military power is placed in the DMZ area, few troops will be left for the defense of home front. In addition, if the ROK army continues to reduce the troops, it can allow North Korea to have asymmetrical superiority in military force and it will eventually exert negative influence on the stability and peace of the Korean peninsular. On the other hand, it should be reminded that, during the Korean War, the Republic of Korea was attacked by North Korea, though it kept 53.3% of troops, compared to North Korea. It should also be reminded that, as of 2008, the ROK army is defending its territory with the troops 55.04% of North Korea. Moreover, the national defense is assisted by 25,120 troops of the US Forces in Korea. In case the total number of the ROK troops falls below 43.4% of the North Korean army, it may cause social unrest about the national security and may lead North Korea's misjudgement. Besides, according to Lanchester strategy, the party with weaker military power (60% compared to the party with stronger military power) has the 4.1% of winning possibility. Therefore, if we consider the fact that the total number of the ROK army troops is 55.04% of that of the North Korean army, the winning possibility of the ROK army is not higher than 4.1%. If the total number of ROK troops is reduced to 43.4% of that of North Korea, the winning possibility will be lower and the military operations will be in critically difficult situation. [Military Reform Plan 2020] rums at the reduction of troops and units of the ground forces under the policy of 'select few'. However, the problem is that the financial support to achieve this goal is not secured. Therefore, the promotion of [Military Reform Plan 2020] may cause the weakening of military defence power in 2020. Some advanced countries such as Japan, UK, Germany, and France have promoted the policy of 'select few'. However, what is to be noted is that the national security situation of those countries is much different from that of Korea. With the collapse of the Soviet Unions and European communist countries, the military threat of those European advanced countries has almost disappeared. In addition, the threats those advanced countries are facing are not wars in national level, but terrorism in international level. To cope with the threats like terrorism, large scaled army trops would not be necessary. So those advanced European countries can promote the policy of 'select few'. In line with this, those European countries put their focuses on the development of military sections that deal with non-military operations and protection from unspecified enemies. That is, those countries are promoting the policy of 'select few', because they found that the policy is suitable for their national security environment. Moreover, since they are pursuing common interest under the European Union(EU) and they can form an allied force under NATO, it is natural that they are pursing the 'select few' policy. At present, NATO maintains the larger number of troops(2,446,000) than Russia(l,027,000) to prepare for the potential threat of Russia. The situation of japan is also much different from that of Korea. As a country composed of islands, its prime military focus is put on the maritime defense. Accordingly, the development of ground force is given secondary focus. The japanese government promotes the policy to develop technology-concentrated small size navy and air-forces, instead of maintaining large-scaled ground force. In addition, because of the 'Peace Constitution' that was enacted just after the end of World War II, japan cannot maintain troops more than 240,000. With the limited number of troops (240,000), japan has no choice but to promote the policy of 'select few'. However, the situation of Korea is much different from the situations of those countries. The Republic of Korea is facing the threat of the North Korean Army that aims at keeping a large-scale military force. In addition, the countries surrounding Korea are also super powers containing strong military forces. Therefore, to cope with the actual threat of present and unspecified threat of future, the importance of maintaining a carefully calculated large-scale military force cannot be denied. Furthermore, when considering the fact that Korea is in a peninsular, the Republic of Korea must take it into consideration the tradition of continental countries' to maintain large-scale military powers. Since the Korean War, the ROK army has developed the technology-force combined military system, maintaining proper number of troops and units and pursuing 'select few' policy at the same time. This has been promoted with the consideration of military situation in the Koran peninsular and the cooperation of ROK-US combined forces. This kind of unique military system that cannot be found in other countries can be said to be an insightful one for the preparation for the actual threat of North Korea and the conflicts between continental countries and maritime countries. In addition, this kind of technology-force combined military system has enabled us to keep peace in Korea. Therefore, it would be desirable to maintain this technology-force combined military system until the reunification of the Korean peninsular. Furthermore, it is to be pointed out that blindly following the 'select few' policy of advanced countries is not a good option, because it is ignoring the military strategic situation of the Korean peninsular. If the Republic of Korea pursues the reduction of troops and units radically without consideration of the threat of North Korea and surrounding countries, it could be a significant strategic mistake. In addition, the ROK army should keep an eye on the fact the European advanced countries and Japan that are not facing direct military threats are spending more defense expenditures than Korea. If the ROK army reduces military power without proper alternatives, it would exert a negative effect on the stable economic development of Korea and peaceful reunification of the Korean peninsular. Therefore, the desirable option would be to focus on the development of quality of forces, maintaining proper size and number of troops and units under the technology-force combined military system. The tableau above shows that the advanced countries like the UK, Germany, Italy, and Austria spend more defense expenditure per person than the Republic of Korea, although they do not face actual military threats, and that they keep achieving better economic progress than the countries that spend less defense expenditure. Therefore, it would be necessary to adopt the merits of the defense systems of those advanced countries. As we have examined, it would be desirable to maintain the current size and number of troops and units, to promote 'select few' policy with increased defense expenditure, and to strengthen the technology-force combined military system. On the basis of firm national security, the Republic of Korea can develop efficient policies for reunification and prosperity, and jump into the status of advanced countries. Therefore, the plans to reduce troops and units in [Military Reform Plan 2020] should be reexamined. If it is difficult for the ROK army to maintain its size of 655,000 troops because of low birth rate, the plans to establish the prompt mobilization force or to adopt drafting system should be considered for the maintenance of proper number of troops and units. From now on, the Republic of Korean government should develop plans to keep peace as well as to prepare unexpected changes in the Korean peninsular. For the achievement of these missions, some options can be considered. The first one is to maintain the same size of military troops and units as North Korea. The second one is to maintain the same level of military power as North Korea in terms of military force index. The third one is to maintain the same level of military power as North Korea, with the combination of the prompt mobilization force and the troops in active service under the system of technology-force combined military system. At present, it would be not possible for the ROK army to maintain such a large-size military force as North Korea (1,190,000 troops and 86 units). So it would be rational to maintain almost the same level of military force as North Korea with the combination of the troops on the active list and the prompt mobilization forces. In other words, with the combination of the troops in active service (60%) and the prompt mobilization force (40%), the ROK army should develop the strategies to harmonize technology and forces. The Korean government should also be prepared for the strategic flexibility of USFK, the possibility of American policy change about the location of foreign army, radical unexpected changes in North Korea, the emergence of potential threat, surrounding countries' demand for Korean force for the maintenance of regional stability, and demand for international cooperation against terrorism. For this, it is necessary to develop new approaches toward the proper number and size of troops and units. For instance, to prepare for radical unexpected political or military changes in North Korea, the Republic of Korea should have plans to protect a large number of refugees, to control arms and people, to maintain social security, and to keep orders in North Korea. From the experiences of other countries, it is estimated that 115,000 to 230,000 troops, plus ten thousands of police are required to stabilize the North Korean society, in the case radical unexpected military or political change happens in North Korea. In addition, if the Republic of Korea should perform the release of hostages, control of mass destruction weapons, and suppress the internal wars in North Korea, it should send 460,000 troops to North Korea. Moreover, if the Republic of Korea wants to stop the attack of North Korea and flow of refugees in DMZ area, at least 600,000 troops would be required. In sum, even if the ROK army maintains 600,000 troops, it may need additional 460,000 troops to prepare for unexpected radical changes in North Korea. For this, it is necessary to establish the prompt mobilization force whose size and number are almost the same as the troops in active service. In case the ROK army keeps 650,000 troops, the proper number of the prompt mobilization force would be 460,000 to 500,000.

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참깨의 발아특성(發芽特性)에 관(關)한 연구(硏究) (Studies on the Germination Characteristics of Sesame (Sesamum indicum L.))

  • 김충수
    • 농업과학연구
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    • 제10권1호
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    • pp.28-60
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    • 1983
  • 본(本) 연구(硏究)는 참깨종자(種子)의 발아(發芽)에 미치는 온도(溫度), 수분(水分), 산소(酸素) 및 관(光) 등(等)의 외적(外的) 조건(條件)의 영향(影響) 발아진행중(發芽進行中)의 종자내(種子內) 물질변화(物質變化)를 구명(究明)하고져 수행(遂行) 되었던 바 그 결과(結果)를 요약(要約)하면 다음과 같다. 1. $35^{\circ}C$부터 $5^{\circ}C$ 간격(間隔)으로 $20^{\circ}C$까지는 평균(平均) 95.8~97.2%의 발아율(發芽率)을 보였고 이들 온도간(溫度間)에는 평균발아율(平均發芽率)의 유의차(有意差)가 인정(認定)되지 않았으나 $15^{\circ}C$에서는 발아율(發芽率)의 급격(急激)한 감소(減少)를 보여 평균(平均) 32.2% 발아(發芽)되었고 이때 변이계수(變異係數)는 77%였다. 2. 온도(溫度)에 따르는 발아소요일수(發芽所要日數)는 $35{\sim}25^{\circ}C$에서 평균(平均) 1.16~1.64일(日)이었으며 $20^{\circ}C$에서는 3.07일(日)이었고 $15^{\circ}C$에서는 10.40일(日)이었다. 3. 발아율(發芽率) 및 발아소요일수(發芽所要日數)를 감안(勘案)할때 $15^{\circ}C$가 참깨종자(種子)의 발아한계온도(發芽限界溫度)였으며 참깨 종자(種子)의 저온발아성(低溫發牙性) 검정(檢定)에 가장 효과적(效果的)인 온도(溫度)로 고려(考慮)되었다. 4. Shirogoma, Turkey등(等)이 가장 저온발아성(低溫發牙性)이 높았고 수원(水原)29호(號), 내복, IS58이 그 다음이었으며, 70~80%의 비교적(比較的) 높은 발아율(發芽率)을 보이는 품종(品種)들이 매포, 수원(水原)14호(號), 김포, 문덕, 해남이었는데, 이들 저온발아성(低溫發牙性)이 비교적(比較的) 높은 품종(品種)은 전공시품종(全供試品種)(90품종(品種))의 10%였으며 이들중 70%는 국내품종(國內品種)이었다. 5. $12^{\circ}C$에서 Shirogoma만 50% 이상(以上)의 발아율(發芽率)을 보였으며 대부분(大部分) 20%미만(未滿)의 낮은 발아율(發芽率)을 보였는데 파종후(播種後) 18일(日)에 온도(溫度)를 $27^{\circ}C$로 상승(上昇)시켰던바 2일이내(日以內)에 전품종(全品種)에서 90% 이하(以上)의 발아율(發芽率)을 보였으며 변온처리(變溫處理)에 따르는 품종간(品種間) 발아율간(發芽率間)에는 유의차(有意差)가 없었고 발아소요일수(發芽所要日數) 간(間)에는 청송, 의상천, 산동, 마산 등은 현저(顯著)히 소요일수(所要日數)가 길었다. 6. 발아(發芽)에 필요한 흡수율(吸水率)은 $25^{\circ}C$적습하(適濕下)에서 48%내지 62%로서 품종간(品種間)에 현저(顯著)한 차이(差異)를 나타내었다. 또한 치상후(置床後), 2시간에 발아(發芽)에 소요(所要)되는 전체 수분(水分)의 63% 정도가 흡수(吸收)되었다. 7. 포화수분하(飽和水分下)에서는 전공시품종(全供試品種)에서 평균발아율(平均發芽率)이 0.42%였고 -0.4bar에서는 64.8%였으며 -0.4~-5.5bar에서 가장 발아율(發芽率)이 높았고 이보다 토양수분(土壤水分)이 부족(不足)할 경우 발아율(發芽率)은 거의 직선적(直線的)인 감소(減少)를 보였다. 8. 10개(個) 공시품종중(供試品種中) 6개공시품종(個供試品種)에서는 5%의 산소하(酸素下)에서 발아(發芽)에 영향(影響)을 받지 않았으나 예천, PI158073, IS103, 의상천의 4품종(品種)은 산소농도(酸素濃度) 5%에서는 발아율(發芽率)이 64~91%로 저하(低下)되었다. 또한 무산소하(無酸素下)에서는 하배축(下胚軸)만 출현(出現)하였을뿐 자엽(子葉)의 출현(出現)은 없었으며 하배축(下胚軸) 출현(出現)은 IS103이 현저(顯著)히 낮았다. 9. 청송, Early Russian 및 수원(水原)9호(號)는 12시간(時間) 흡습(吸濕)시킨 후(後) 24시간(時間) 건조(乾燥)시킬때 청송만 27.5%의 발아율(發芽率)을 보였고 수원(水原)9호(號) 및 Early Russian은 전혀 발아(發芽)되지 않았으며 IS103은 4시간 흡습후(吸濕後) 24시간(時間) 건조시(乾燥時) 발아율(發芽率)이 감소(減少)되었는데 24시간(時間) 흡습후(吸濕後) 24시간(時間) 건조시(乾燥時)에도 32.5%의 발아율(發芽率)을 보였다. 10. 발아(發芽)의 진행(進行)에 따라 종자내(種子內) 당함량(糖含量)은 급격(急激)한 증가(增加)를 보였으나 전분함량(澱粉含量)은 현저(顯著)히 감소(減少)되었으며 ${\alpha}$-amylase의 활성도(活性度)는 점증(漸增)되었는데 이들 증감정도(增減程度)는 $25^{\circ}C$에 비해 $15^{\circ}C$에서는 현저(顯著)히 낮았다. 11. 발아(發芽)가 진전(進展)됨에 따라 종자(種子)의 지질함량(脂質含量)은 급격(急激)한 감소(減少)를 보였고 alkaline lipase의 활성도(活性度)는 특히 발아초기(發芽初期)에 더욱 급격(急激)한 증가(增加)를 보였는데 지질(脂質)의 감소정도(減少程度)와 alkaline lipase의 활성도(活性度) 증가정도(增加程度)는 $25^{\circ}C$에 비해 $15^{\circ}C$에서 현저(顯著)히 낮았다. 12. 6개공시품종중(個供試品種中) 4개공시품종(個供試品種)의 발아(發芽)에는 광파장(光波長)의 영향(影響)을 받지 않았으나 수원(水原)8호(號)는 600~650nm에서 IS103은 600~650nm, 500~550nn에서 현저(顯著)히 발아율(發芽率)이 저하(低下)되었으며 수원(水原)8호(號)는 600~760nm 및 500~560nm에서, IS103은 400~470nm 및 암흑상태(暗黑狀態)에서 높은 발아율(發芽率)을 보였다. 13. 100입중(粒重)이 무거운 종자(種子)에서 각(各) 품종(品種)의 발아율(發芽率)이 현저(顯著)히 높았으며 파종심도(播種深度) 4 cm 하(下)에서는 청송 및 Early Russian은 전혀 자엽(子葉)이 출현(出現)되지 않았던 반면(反面), 수원(水原)9호(號) 및 IS103은 각각(各各) 32.5 및 50%의 발아율(發芽率)을 보였다. 또한 참깨의 지상부(地上部), 지하부(地下部) 및 재배지토양(栽培地土壤) 추출물(抽出物)은 발아(發芽)에 전혀 영향(影響)을 미치지 않았다. 14. 무피복구(無被覆區)에 비해 흑색(黑色) 및 투명(透明) polyethylene film 피복구(被覆區)에서 발아율(發芽率)이 현저(顯著)히 높았고, 발아소요일수(發芽所要日數)는 현저(顯著)이 단축(短縮)되었으며 또한 초기생육(初期生育) 및 주당삭수와 주당수량(株當收量)이 현저(顯著)히 증가(增加)되었는데 polyethylene film의 종류간(種類間)에는 유의차(有意差)가 인정(認定)되지 않았으나 흑색(黑色)polyethylene film보다는 투명(透明) polyethylene film이 약간(若干) 더 효과적(效果的)인 경향(傾向)이었다. 15. 심천, 청송, 수원(水原)9호(號), PI158073 및 IS103은 수분흡수율(水分吸收率)이 현저(顯著)히 낮았고 흡습후(吸濕後) 종자중(種子重)의 증가(增加)는 수원(水原)8호(號), 수원(水原)26호(號), Orotall 및 의상천이 현저(顯著)히 컸다.

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