• Title/Summary/Keyword: Field study

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History of Plant Protection Science since 1900 in Korea (한국(韓國)에 있어서의 식물보호(植物保護) 연구사(硏究史) -1900년대(年代)를 중심(中心)으로-)

  • Park, Jong-Seong
    • Korean Journal of Agricultural Science
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    • v.6 no.1
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    • pp.69-95
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    • 1979
  • The study was conducted to search developmental process of plant protection science from review of forty-three hundreds literatures presented since 1900 in Korea and to forecast future statues of the science to be done. About 80 percent of literatures related to plant protection science such as plant pathology, applied entomology, weed science and agricultural pharmacology were collected from publications of agricultural and forestry reseach organizations attached to Office of Rural Development and Office of Forestry. The rest of literatures were mainly collected from Korean Journal of Plant Protection Society and small number of literatures were also collected from publications of the other journals of crop science and thesis collection of agricultural colleges. In Korea, research organizations of plant protection science are divided into two main groups such as exclusive agricultural research organizations and agricultural colleges. It is pointed out that the former contributions to plant protection science are very great compared to those of the latter since 1900. From periodical consideration of developmental process of the science since 1900, the history or the science are divided into three eras such as introduction and sprout of modern plant protection science during the first forty years, distress of the science during the following twenty years including the Second World War and the Korean War and rapid growth of the science after 1961. In spite of long time distress of the science during the Second World War and the Korean War, the researches on plant protection science in post-war have been done twice as many as pre-war. From consideration of the subject plants in researches of plant protection, it is shown that a great many researches on protection of rice plant have been done and occupy 37 percent of plant protection researches since 1900. And also researches on protection of fruit-trees and cash-crops are not so many as those of rice plant but have been done in noticeable numbers. In fact, researches on protection of fruit-trees and cashcrops were the most important subjects of plant protection researches in pre-war while those of rice plant were the most important subjects after 1930, particulary in post-war. From consideration of contents of plant protection researches, it is said that more fundamental researches than applied ones such as practical control methods of diseases, insect pests and weeds were done in pre-war while more applied researches than fundamental ones were done in post-war, Among applied researches, those of chemical control were the most important subjects. Researches on disease and insect-pest resistance have been done in both pre-war and post-war while researches on forecasting of disease and insect-pest and race of plant pathogens have been done in post-war. And also researches on weed control mainly have been done after 1960. Researches on agricultural chemicals for control of diseases, insect pests and weeds still belong to a new field which must be expected in future, and there is nothing to notice with the exception of practical application of agricultural chemicals introduced from foreign countries. Some of important researches on diseases and insect pests were discussed in relation to developmental process of plant protection science in Korea since 1900. In future, researches on plant protection will be develop to the direction supporting importance of integrated control for plant protection. Therefore, it is pointed out that security of highly educated and trained scientists with enlargement of reseach fields of plant protection science are necessary and role of agricultural colleges for future development of the science must be emphasized.

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A Study for the Norms of Audiometric Tests in Koreans (정상한국인의 청력검사치에 관한 연구)

  • 오혜경;서장수;이근해;김희남;김영명;권영화;서옥기
    • Proceedings of the KOR-BRONCHOESO Conference
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    • 1981.05a
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    • pp.38.1-38
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    • 1981
  • Currently in the otologic field, there are various methods of special audiometric examinations, such as, tone decay, SISI, and impedance audiometry and only a few studies has been done in these fields sporadically in Korea. The purpose of this paper is to establish norms of various special audiometric tests, so we have performed the special audiometric tests on 100 male medical students in good physical condition and the follow results were obtained. 1. All cases showed over 90% of PB scores. The mean and its 2 S.D. were 98$\pm$4.9% in the right ear and 97$\pm$5.6% in the left ear. 2. The mean and its 2 S.D. of MCL(most comfortable level) were 45$\pm$15.4 dB in the right ear and 46$\pm$17.9 dB in the left ear, and its range was 12$\pm$12.2 dB in the right ear and 13$\pm$12.6 dB in the left ear. 3. The mean and its 2 S.D. of UCL (uncomfortable level) were 102$\pm$7.9 dB in the right ear and 102$\pm$7.9 dB in the left ear and about an half in cases showed over 106 dB of UCL. 4. In 95% of cases, SISIs(short increment sensitivity index) at 1, 000 Hz and 4000 Hz was below 45% in the right ear in both frequencies and below 55% and 75% in the left ear, respectively. 5. In 95% of cases, tone decays at 2, 000 Hz and 4, 000 Hz was below 10 dB in both ears. 6. The difference between SRT and PTA (speech reception threshold minus pure tone average) was 4$\pm$9.2 dB in the right ear and 4$\pm$10.0 dB in the left ear. 7. The dynamic range(uncomfortable level minus speech reception threshold) was 98$\pm$13.5 dB in the right ear and 99$\pm$13.5 dB in the left ear. We had trouble in estimating the dynamic range in about an half in cases, in which we couldn't estimate the UCL with our conventional audiometry. 8. The results of impedance audiometric tests were as follow: A. In the tympanogram, all cases were of A type with one exception of B type in the left ear. The mean and its 2 S.D. of its peak level were 22.8$\pm$32.94mm $H_2O$ in the right ear and 23.9$\pm$29. 81mm $H_2O$ in the left ear. B. The mean and its 2 S.D. of the compliance were 0.6$\pm$0.54cc in the right ear and 0.6$\pm$0.53cc in the left ear. C. The results of stapedial reflex: a. The mean and its 2 S.D. of the controlateral stapedial reflex at 500Hz, 1, 000Hz, 2, 000Hz, 4, 000Hz were 99$\pm$17.7 dB, 87$\pm$14.4 dB, 79$\pm$13.7 dB, 77$\pm$20.0 dB in the right ear and 99$\pm$15.9 dB, 88$\pm$13.9 dB, 79$\pm$13.7 dB, 77$\pm$21.3 dB in the left ear. Depending on the tested frequencies, the stapedial reflex wasn't generated in 6 cases in the right ear and 11 cases in the left ear. b. The mean and its 2 S.D. of the ipsilateral stapedial reflex at 1, 000Hz, and 2, 000Hz were 89$\pm$16.3 dB, 82$\pm$15.9 dB in the right ear and 89$\pm$18.0 dB, 83$\pm$18.9 dB in the left ear. Depending on the tested frequencies, the stapedial reflex wans't generated in 1 case in the right ear and 2 cases in the left ear. 9. Eustachian tube function using with impedance audiometry was malfunctioned in21 cases depending on the tested pressure and the range of peak level of tympanogram was 14$\pm$26.9mm $H_2O$(tested pressure:+250mm $H_2O$), 8$\pm$21.9mm $H_2O$ (tested pressure:-250mm $H_2O$) in the right ear and 11 cases depending on the tested pressure and the range of the peak level of tympanogram was 12$\pm$22.5mm $H_2O$ (tested pressure: +250 mm $H_2O$, 9$\pm$17.3mm $H_2O$(tested pressure: -250mm $H_2O$) in the left ear.

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The Effect on Air Transport Sector by Korea-China FTA and Aviation Policy Direction of Korea (한·중 FTA가 항공운송 부문에 미치는 영향과 우리나라 항공정책의 방향)

  • Lee, Kang-Bin
    • The Korean Journal of Air & Space Law and Policy
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    • v.32 no.1
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    • pp.83-138
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    • 2017
  • Korea-China FTA entered into force on the 20th of December 2015, and one year elapsed after its effectuation as the FTA with China, our country's largest trading partner. Therefore, this study looks at the trends of air transport trade between Korea and China, and examines the contents of concessions to the air transport services sector in Korea-China FTA, and analyzes the impact on the air transport sector by Korea-China FTA, and proposes our country's aviation policy direction in order to respond to such impact. In 2016 the trends of air transport trade between Korea and China are as follows : The export amount of air transport trade to China was 40.03 billion dollars, down by 9.3% from the last year, and occupied 32.2% of the total export amount to China. The import amount of air transport trade from China was 24.26 billion dollars, down by 9.1% from the last year, and occupied 27.7% of the total import amount from China. The contents of concessions to the air transport services sector in Korea-China FTA are as follows : China made concessions to the aircraft repair and maintenance services and the computer reservation system services with limitations on market access and national treatment in the air transport services sector of the China Schedule of Specific Commitments of Korea-China FTA Chapter 8 Annex. Korea made concessions to the computer reservation system services, selling and marketing of air transport services, and aircraft repair and maintenance without limitations on market access and national treatment in the air transport services sector of the Korea Schedule of Specific Commitments of Korea-China FTA Chapter 8 Annex. The impact on the air transport sector by Korea-China FTA are as follows : As for the impact on the air passenger market, in 2016 the arrival passengers of the international flight from China were 9.96 million, up by 20.6% from the last year, and the departure passengers to China were 9.90 million, up by 34.8% from the last year. As for the impact on the air cargo market, in 2016 the exported goods volumes of air cargo to China were 105,220.2 tons, up by 6.6% from the last year, and imported goods volumes from China were 133,750.9 tons, up by 12.3% from the last year. Among the major items of exported air cargo to China, the exported goods volumes of benefited items in the Tariff Schedule of China of Korea-China FTA were increased, and among the major items of imported air cargo from China, the imported goods volumes of benefited items in the Tariff Schedule of Korea of Korea-China FTA were increased. As for the impact on the logistics market, in 2016 the handling performance of exported air cargo to China by domestic forwarders were 119,618 tons, down by 2.1% from the last year, and the handling performance of imported air cargo from China were 79,430 tons, down by 4.4% from the last year. In 2016 the e-commerce export amount to China were 109.16 million dollars, up by 27.7% from the last year, and the e-commerce import amount from China were 89.43 million dollars, up by 72% from the last year. The author proposes the aviation policy direction of Korea according to Korea-China FTA as follows : First, the open skies between Korea and China shall be pushed ahead. In June 2006 Korea and China concluded the open skies agreement within the scope of the third freedom and fourth freedom of the air for passenger and cargo in Sandong Province and Hainan Province of China, and agreed the full open skies of flights between the two countries from the summer season in 2010. However, China protested against the interpretation of the draft of the memorandum of understanding to the air services agreement, therefore the further open skies did not take place. Through the separate aviation talks with China from Korea-China FTA, the gradual and selective open skies of air passenger market and air cargo market shall be pushed ahead. Second, the competitiveness of air transport industry and airport shall be secured. As for the strengthening methods of the competitiveness of Korea's air transport industry, the support system for the strengthening of national air carriers' competitiveness shall be prepared, and the new basis for competition of national air carriers shall be made, and the strategic network based on national interest shall be built. As for the strengthening methods of the competitiveness of Korea's airports, particularly Incheon Airport, the competitiveness of the network for aviation demand creation shall be strengthened, and the airport facilities and safety infrastructure shall be expanded, and the new added value through the airport shall be created, and the world's No.1 level of services shall be maintained. Third, the competitiveness of aviation logistics enterprises shall be strengthened. As for the strengthening methods of the competitiveness of Korea's aviation logistics enterprises, as the upbringing strategy of higher added value in response to the industry trends changes, the new logistics market shall be developed, and the logistics infrastructure shall be expanded, and the logistics professionals shall be trained. Additionally, as the expanding strategy of global logistics market, the support system for overseas investment of logistics enterprises shall be built, and according to expanding the global transport network, the international cooperation shall be strengthened, and the network infrastructure shall be secured. As for the strengthening methods of aviation logistics competitiveness of Incheon Airport, the enterprises' demand of moving in the logistics complex shall be responded, and the comparative advantage in the field of new growth cargo shall be preoccupied, and the logistics hub's capability shall be strengthened, and the competitiveness of cargo processing speed in the airport shall be advanced. Forth, in the subsequent negotiation of Korea-China FTA, the further opening of air transport services sector shall be secured. In the subsequent negotiation being initiated within two years after entry into force of Korea-China FTA, it is necessary to ask for the further opening of the concessions of computer reservation system services, and aircraft repair and maintenance services in which the concessions level of air transport services sector by China is insufficient compared to the concessions level in the existing FTA concluded by China. In conclusion, in order to respond to the impact on Korea's air passenger market, air cargo market and aviation logistics market by Korea-China FTA, the following policy tasks shall be pushed ahead : Taking into consideration of national air carriers' competitiveness and nation's benefits, the gradual and selective open skies shall be pushed ahead, and the support system to strengthen the competitiveness of air transport industry and airport shall be built, and entry into aviation logistics market by logistics enterprises shall be expanded, and the preparations to ask for the further opening of air transport services sector, low in the concessions level by China shall be made.

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An Analytical Study on the Stem-Growth by the Principal Component and Canonical Correlation Analyses (주성분(主成分) 및 정준상관분석(正準相關分析)에 의(依)한 수간성장(樹幹成長) 해석(解析)에 관(關)하여)

  • Lee, Kwang Nam
    • Journal of Korean Society of Forest Science
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    • v.70 no.1
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    • pp.7-16
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    • 1985
  • To grasp canonical correlations, their related backgrounds in various growth factors of stem, the characteristics of stem by synthetical dispersion analysis, principal component analysis and canonical correlation analysis as optimum method were applied to Larix leptolepis. The results are as follows; 1) There were high or low correlation among all factors (height ($x_1$), clear height ($x_2$), form height ($x_3$), breast height diameter (D. B. H.: $x_4$), mid diameter ($x_5$), crown diameter ($x_6$) and stem volume ($x_7$)) except normal form factor ($x_8$). Especially stem volume showed high correlation with the D.B.H., height, mid diameter (cf. table 1). 3) (1) Canonical correlation coefficients and canonical variate between stem volume and composite variate of various height growth factors ($x_1$, $x_2$ and $x_3$) are ${\gamma}_{u1,v1}=0.82980^{**}$, $\{u_1=1.00000x_7\\v_1=1.08323x_1-0.04299x_2-0.07080x_3$. (2) Those of stem volume and composite variate of various diameter growth factors ($x_4$, $x_5$ and $x_6$) are ${\gamma}_{u1,v1}=0.98198^{**}$, $\{{u_1=1.00000x_7\\v_1=0.86433x_4+0.11996x_5+0.02917x_6$. (3) And canonical correlation between stem volume and composite variate of six factors including various heights and diameters are ${\gamma}_{u1,v1}=0.98700^{**}$, $\{^u_1=1.00000x_7\\v1=0.12948x_1+0.00291x_2+0.03076x_3+0.76707x_4+0.09107x_5+0.02576x_6$. All the cases showed the high canonical correlation. Height in the case of (1), D.B.H. in that of (2), and the D.B.H, and height in that of (3) respectively make an absolute contribution to the canonical correlation. Synthetical characteristics of each qualitative growth are largely affected by each factor. Especially in the case of (3) the influence by the D.B.H. is the most significant in the above six factors (cf. table 2). 3) Canonical correlation coefficient and canonical variate between composite variate of various height growth factors and that of the various diameter factors are ${\gamma}_{u1,v1}=0.78556^{**}$, $\{u_1=1.20569x_1-0.04444x_2-0.21696x_3\\v_1=1.09571x_4-0.14076x_5+0.05285x_6$. As shown in the above facts, only height and D.B.H. affected considerably to the canonical correlation. Thus, it was revealed that the synthetical characteristics of height growth was determined by height and those of the growth in thickness by D.B.H., respectively (cf. table 2). 4) Synthetical characteristics (1st-3rd principal component) derived from eight growth factors of stem, on the basis of 85% accumulated proportion aimed, are as follows; Ist principal component ($z_1$): $Z_1=0.40192x_1+0.23693x_2+0.37047x_3+0.41745x_4+0.41629x_5+0.33454x_60.42798x_7+0.04923x_8$, 2nd principal component ($z_2$): $z_2=-0.09306x_1-0.34707x_2+0.08372x_3-0.03239x_4+0.11152x_5+0.00012x_6+0.02407x_7+0.92185x_8$, 3rd principal component ($z_3$): $Z_3=0.19832x_1+0.68210x_2+0.35824x_3-0.22522x_4-0.20876x_5-0.42373x_6-0.15055x_7+0.26562x_8$. The first principal component ($z_1$) as a "size factor" showed the high information absorption power with 63.26% (proportion), and its principal component score is determined by stem volume, D.B.H., mid diameter and height, which have considerably high factor loading. The second principal component ($z_2$) is the "shape factor" which indicates cubic similarity of the stem and its score is formed under the absolute influence of normal form factor. The third principal component ($z_3$) is the "shape factor" which shows the degree of thickness and length of stem. These three principal components have the satisfactory information absorption power with 88.36% of the accumulated percentage. variance (cf. table 3). 5) Thus the principal component and canonical correlation analyses could be applied to the field of forest measurement, judgement of site qualities, management diagnoses for the forest management and the forest products industries, and the other fields which require the assessment of synthetical characteristics.

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ON THE EFFECTS CHLORINITIES UPON GROWTH OF EARLIER LARVAE AND POST-LARVA OF A FRESH WATER PRAWN, MACROBRACHIUM ROSENBERGI(DE MAN) (담수산새우 Macrobrachium rosenbergi (de Man)의 초기유생 및 Post-larva.의 성장에 미치는 염분량에 관하여)

  • KWON Chin Soo;UNO Yutaka;OGASAWARA Yohismitsu
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.10 no.2
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    • pp.97-114
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    • 1977
  • The fresh water prawn, Macrobrachium rosenbergi(de Man) is a very common species in Indopacific region, which inhaits both fresh and brackish water in low land area, most of rivers and especially aboundant in the lower reaches which are influenced by sea water. It is one of the largest and commercial species of genus Macrobrachium, which is commonly larger than $18\~21cm$ in body length, from the basis of eye-stalked to the distal of telson. As a part of the researches in order to investigate the possibilities on transplantation and propagation of this species, this work dealt with the problems on the effects of chlorinities upon zoeal larvae and post-larvae 1). metamorphosis rate and optimum chlorinity for metamorphosis to post-larve, 2). tolerance and comparative survival rate on various chlorinties, from fresh water to sea water $(19.38\%_{\circ}\;Cl)$, which reared for six days upon each stage of zoeal larvae, 3). accomodation rate on chlonities which reared for twelve days after transmigration into variant chlorinities of the range from $3.68\%_{\circ}$ Cl to $1.53\%_{\circ}$ Cl in the way of rearing of the range from $3.82\%_{\circ}$ Cl to $11.05\%_{\circ}$ upon each stage of zoea, 4). tolerance on both of fresh and sea water upon zoeal larva and post-larva under the condition of $28^{\circ}C{\pm}1$ in temperature and feeding on Artenia salina nauplii, 5). relationship between various chlorinities and grwth of post-larvae under the condition of $28^{\circ}C$ in tmperature and feeding on meat of clam. Thus these investigations were performed in order to grope for a comfortable method on seedmass production. Up to the present, the study on the effects of chlorinity upon earlier zoeal larvae and post-larvae of Macrobrachium species has been scarcely performed by workers with the exception of Lewis(1961) and Ling (1962,, 1967), even so their works were not so detailed. On the other hand, larvae of several species of this genus were reared at the water which mixed sea water so as to carry out complete metamorphosis to post-larva by workers in order to investigate on earlier 1 arval and earlier post-larval development, such as Macrobrachium lamerrei (Rajyalakshmi, 1961), M. rosenbergi and M. nipponense (Uno and Kwoa, 1969; Kwon and Uno, 1969), M. acanthurs (Choudhury, 1970; Dobkin, 1971), M. carcinus(Choudhury, 1970), M. formosense(Shokita, 1970), M. olfersii (Duggei et al., 1975), M. novaehallandiae (Greenwood et al., 1976), M. japonicum (Kwon, 1974) and M. lar (Shokita, personal communication), and there fore it is regarded that chlorinity is, generally, one of absolute factors to rear zoeal larvae of brackish species of Macrobrachium genus. Synthetic results on this work is summarized as the follwings: 1) Zoeal larvae required different chlorinities to grow according to each stage, and generally, it is regarded that optimum range of living and growing is from $7.63\%_{\circ}Cl\to\;7.63\%_{\circ}Cl$, and while differences of metamorphsis rate, from first zoea to post-larva, is rarely found in this range, and however it occurs apparently in both of situation at $7.63\%_{\circ}Cl$ below and $16.63\%_{\circ}Cl$ above and moreover, metamorphosis rate is delayed somewhat in case of lower chlorinity as compared with high chlorinity in these situations. 2) Accomodation in each chlorinity on the range, from fresh water to sea water, is different according to larval stages and while the best of it is, generally, on the range from $14.24\%_{\circ}Cl$ to $8.28\%_{\circ}Cl$ and favorite chlorinity of zoea have a tendency to remove from high chlorinity to lower chlorinity in order to advance larval age throughout all zoeal stages, setting a conversional stage for eighta zoea stage. 3) Optimum chlorinity of living and growth upon postlarvae is on the range of $4.25\%_{\circ}Cl$ below, and in proportion as approach to fresh water, growth rate is increased. 4) Post-large are able to live better in fresh water in comparison with zoeal larvae, which are only able to live within fifteen hours, and by contraries, post-larvae are merely able to live for one day as compared with ?미 larvar, which are able to live for six days more in sea water $19.38\%_{\circ}Cl\;above$. 5) Also, in case of transmigration into higher and lower chlorinities in the way of rearing in the initial chlorinities $ 3.82\%_{\circ}Cl,\;7.14%_{\circ}Cl\;and\;11.05%_{\circ}Cl$, accoodation rate is a follow: accomodation capacity in ease of removing into higher chlorinities from lower chlorinities is increased in proportion as earlier stages, setting a conversional stage for eighth zoea stage, and by contraries, in case of advanced stages from eighth zoea it is incraesed in proportion as approach to post-larva stage in the case of transmigration into lower chlorinity from higher chlorinity. On the other hand, it is interesting that in case of reciprocal transmigration between two different chlorinitiess, each survival rate is different, and in this case, also, its accomodation in each zoea stage has a tendency to vary according to larval stages as described above, setting a conversional stage for eighth zoea stage. 6) It is likely that expension of radish pigments on body surface is directly proportional to chlorinity during the period of zoea rearing, and therefore it seems like all body surfacts of zoea larvae be radish coloured in case of higher chlorinity. 7) By the differences that each zoeal larvae, postlarvae, juvaniles and adult prawn are required different chlorinity for inhabiting in each, it is regarded that this species migrats from up steam to near the estuary of the river which the prawns inhabits commonly in natural field for spawning and growth migration. 8) It had better maintainning chlorinities according to zoeal stage for a comfortable method on seed-mass production that earlier larva stages than eighth zoea are maintained on the range from $8\%_{\circ}Cl\;to\;12\%_{\circ}Cl$ to rear, and later larva stages than eighth zoea, by contraries, are gradually regula ted-to love chlorininity of the range from $7\%_{\circ}Cl\;to\;4\%_{\circ}Cl$ according to advance for post-larva stage.

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