• KOREAN JOURNAL OF CROP SCIENCE
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• v.15
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• pp.69-75
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• 1974

This experiment was conducted to investigate the influence of different amount of nitrogen and deficiency of soil moisture on yield components of soybean. Soybean were seeded on 1/2000a wagner pot. Deficiency of soil moisture was treated at each growth atage of soybean. 1.In case of deficiencyt of soil moisture at the flowering time in the plot of non-nitrogen(NO D3), the growth duration of soybean was shortened about three to four days. 2. The leaf area was greatly affected by the influence of both treatments till 49days after germinating. 3.The increase of stem height, stem doameter,number of branches and lengeh of the branches came to an end about 70 days after seeding. These growing condition of tje soybean were lowest the plot of No D$_1$,in which the frowth of the soybeans were poor at the early stage. 4.The number of pods was not increased by the increase of fertilizing nitrogenous fertilizer. The number of pods was much decreased by the influence of soil mousture deiciency, and under this condition, the proportion of main stem pods and two or three grain pods was high. 5.The 3rd and 4h nodes and the 10th to 12th nodes from bottom had more pods than the other nodes had, but of the plants had grown well, they had more pods on the 3rd and 4th nodes, but if the plants had grown poorly, they had more pods on the 10th to 12th nodes. 6.The content of protein in the soybean was low at the plit of N。D$_4$which had not heavy weight of 100 grains, and the content of oil in the soybean was low in the plot in which each plant had a small number of grains.

• Korean Journal of Environmental Agriculture
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• v.17 no.1
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• pp.76-83
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• 1998

The most remarkable aspect in the hormesis law is that dose of harmful agents can produce effect that are diametrically opposite to the effect found with high doses of the same agent. Minute quantities of a harmful agent bring about very small change in the organism and control mechanisms appear to subjugate normal processes to place the organism in a state of albert and repair. The stimulated organism in more responsive to changes in environmental factors than it did before being alerted. Routine functions, including repair and defense, have priority for available energy and matetial. The alerted organism utilizes nutrients more efficiently, grows faster, shows improved defense, and lives longer. Accelerated germination, sprouting, growth, development, blooming and ripening, and increased crop yield and resistance to disease are found in plants. Another concept supported by the data in that low doses of ionizing radiation provide increased resistance to subsequent high doses of radiation. The hormesis varies with subject plant, variety, state of seed, environmental and cultural conditions, physiologic function measured, dose rate and total exposure. The results of hormesis are less consistently found, probably due to the great number of uncontrolled variables in the experiments. The general dosage for radiation homlesis in about 100 (10 to 1,000) times ambient or 100 (10 to 1,000) times less than a definitely harmful dose, but these must be modified to the occasion. Although little is known about most mechanisms of homzesis reaction, overcompensation of repair mechanism is offered as one mechanism.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.413-416
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• 2008

The concrete used most in construction materials. There is an overcrowded iron dimensions use of the concrete at time of the other concrete theory on the reinforcing rod back which did congestion and compares it with this, and there are more few dimensions of the aggregate than concrete, and quantity of aggregate passage is superior in mortar than concrete. If a volume rate of the aggregate writes mortar than concrete against this, therefore, unit amount increases, and quantity of paste increases and quantity of dry shrinkage than increase concrete. However, I let I regulate lay priest distribution of the aggregate, and the results rates increase and reduce unit amount and decrease quantity of dry shrinkage, and separation resistance and the gap passage characteristics are judged because it can be it in a substitute document of very superior concrete. I came to carry out the study that I watched to let I was useful a little more and do the improvement repair of a become building wall body, a basement pillar and repair reinforcement of the assistant in the reinforcing rod back, the old age when I made congestion here. I regulated lay priest distribution of the aggregate in the study and regulated substitution rate of the aggregate (40%, 50%, 60%) and divided W/C 30%, 40% standards and produced mortar and I compared quantity of air by this, slump, compression robbery and showed it this time.

• Proceedings of the Korea Water Resources Association Conference
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• 2018.05a
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• pp.32-32
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• 2018

최근 여러 가지 요인으로 가뭄이 빈발하고 있으며, 가뭄을 대비한 과학적 저수지 운영이 절실하다. 유입량, 관개용수량, 저수량, 하천유지유량 등 저수지 물수지를 반영하여 실제 가뭄 상황에 적용할 수 있는 시스템으로 개발하였다. 여기서, 하류 하천의 수량을 양수하여 저수량을 확보하는 양수저류를 고려하였고, 시기별 관개용수량을 간단관개, 절수관개 등의 실제 상황을 반영하도록 하였다. 또한 저수량의 장기간 변화를 관찰하여 저수지 운영의 가이드라인을 설정할 수 있도록 하였고, 하류 하천의 유량 변화도 평가할 수 있도록 하였다. 최근 수차례 가뭄을 겪은 충남 홍성에 위치한 대사저수지에 개발된 시스템을 적용하였다. 대사 저수지는 유역면적 $2.9km^2$, 유효저수량 137만$m^3$, 수혜면적 163ha에 이르며, 유역면적 $72.2km^2$인 하류하천의 와룡천으로부터 $0.057m^3/s$씩 양수하여 저수량을 확보하고 있다. 일별 저수율 자료가 있는 1991년부터 2016년까지 분석한 결과는 다음과 같다. 양수는 1월 15일부터 5월 31일까지 실시하는 것으로 하고 결과를 정리하였다. 첫째, 일 저수위를 모의하여 검증한 결과 일평균하여 관측 저수위는 EL.84.58m, 모의 저수위는 EL.85.87m이었다. 이 때 강우량은 연평균 1,275.2mm, 유입량은 718.0mm, 유출률 56.3%, 수면증발량 11.5만$m^3$, 관개용수 공급량 117.5만$m^3$, 월류량 148.9만$m^3$이었다. 둘째, 양수로 인한 유입량의 변화는 양수 전에는 연평균 209만$m^3$(유출률 56.3%)에서 양수 후 276만$m^3$(74.7%)로 증가하였고, 양수량은 67.5만$m^3$(연유입량의 32.3%)이었다. 셋째, 하류 와룡천의 유량은 양수 전에는 연평균 연유출량 5,200만$m^3$(유출률 56.5%)에서 양수 후 5,120만$m^3$(55.6%)으로 나타났다. 넷째, 양수 전에는 일평균 저수량이 47만$m^3$에서 양수 후 76만㎥으로 증가하였고, 양수저류로 인해 이수안전도는 15.4%에서 92.3%로 개선되었다. 또한 양수로 인해 저수지 유입량은 연평균 32.3% 증가하였고, 하류하천의 유량은 1.55% 감소하였다. 이상의 분석 결과로 양수저류는 가뭄대응에 상당한 효과가 있다고 평가할 수 있다. 또한 다양한 여건을 고려한 저수지 운영 가이드라인의 합리적 설정으로 보다 적극적인 가뭄대응이 필요하다고 본다. 물관리 현황은 지구별, 저수지별로 다양하다. 향후 현장 상황에 적합한 물관리 방법을 적극 모색해야 하며, 자연과 인간의 평등한 물 이용 환경조성에, 여기 개발한 도구가 일정 부분 유용할 것이라 판단한다.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.32 no.1
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• pp.112-118
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• 1987

This study was carried out to investigate the effects of early planting and polyethylene film (P.E) mulch on early maturing soybean of Korean native cultivar Kyeonggi No. 114 in the Kyeonggi area. It was planted four times at the ten days interval from April I to April 30 in 1985 and 1986. The average soil temperature was 1-5$^{\circ}C$ higher under the polyethylene film mulch condition than the conventional cultural practice condition. Soil moisture content also was higher under P.E mulch condition. Days to emergence was shortened 5-16 days and days to flowering was shortened 3-5 days. The fresh pod yield was increased 12% more at the planting date of April 1 and April 10. Income was increased 70, 83, more at the planting date of April 1 and April 10 under the polyethylene mm mulch conditions.

• The Journal of the Convergence on Culture Technology
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• v.9 no.3
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• pp.633-640
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• 2023

In this study, numerical analysis was performed based on field investigation to derive an appropriate reinforcement method by analyzing the displacement behavior characteristics of concrete blocks generated in the direct fixation track on the bridges of the serviced light rail transit. The track of this study was a direct fixation track on a sharp curved track, and the problem of movement of the concrete blocks installed on the bridge deck in the longitudinal and lateral directions occurred. In this study, based on the finite element model using 3D solid elements, the behavior of the direct fixation track that could be occurred under operating load conditions was analyzed. In addition, the reinforcement effect of various reinforcement methods was analyzed. As a result of analyzing the lateral displacement before and after reinforcement, it was analyzed that the maximum lateral displacement after reinforcement under the extreme lateral wheel loads significantly decreased to about 3% (about 0.1mm) compared to before reinforcement. In addition, as a result of examining the generated stress of the filling mortar, bridge decks, and reinforcing bar, it was analyzed that all of them secured a sufficient safety factor of 2.6 or higher, and the optimal conditions for the reinforcement method were derived. Therefore, it is judged that the number of anchoring reinforcements and symmetrical anchor placement reviewed in this study will be effective in controlling the occurrence of lateral displacement of concrete blocks and securing the structural integrity of bridges and concrete blocks.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.3
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• pp.49-82
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• 1965

For the stable and high yields of low-land rice in Korea, the characteristics of rice plant for the vegetative and physiological responses, plant type formation, and yield components have been studied in order to obtain the fundamental data for the improvement of cultural practices, especially for the ideal fertilizer application. Furthermore the environmental conditions in Korea including temperatures, light, precipitation, and soil conditions have been compared in the broad sense with those in Japan, and the application of nitrogen, phosphorus, potassium, silicate and other micro-nutrients were described in relation to the characteristics of environmental conditions for the improvement of fertilizer application. 1. The average yield of polished-rice per 10 are in Korea is about 204 kg and this values are much less than those in Japan and Taiwan where they produce 77% to 13% more than in Korea. The rate of yield increase a year in Korea is 4.2 kg, but in Japan and Taiwan the rates of yield increase a year are 81 % and 62%, respectively. It was also found that the coefficient of variation of yield is 7.7% in Korea, 6.7% in Japan and 2.5% in Taiwan. This means that the stability of producing rice in Korea is very low when compared with those in Japan and Taiwan. 2. It was learned from the results obtained from the 'annual yield estimation experiment' that there are big differences in the respect of plant type formations between rice crops grown in Japan and Korea. The important differences found were as follows: (1) The numbers of spikelets per 3.3 square meters are 891 in Korea and 1, 007 in Japan(13% more than in Korea). (2) The numbers of tillers per 3.3 square meters at the stage of maximum tillering are 1, 150 in Korea, but in Japan they showed 19% more than in Korea. (3) The ratio of effective tillers to total tillers is 77.5% in Korea and 74.7% in Japan, which seems to be higher in Korea than in Japan. But the ratio in Korea is very low when considered the numbers of total tillers in both countries. (4) The ratio of grain to straw is 85.4% in Korea and 96.3% in Japan. 3. The average temperatures during the growing season at the area of Suwon, Kwangjoo and Taegu are almost same as those in the district of Jookokoo(Fookoo yama) in Japan, i.e., the temperatures during the rice-growing season in Korea are similar to those in the southern-warm regions of Japan. 4. Considering the minimum temperatures at the stage of limiting transplanting, 13$^{\circ}C$, the time of transplanting might be 30 to 40 days earlier than presently practicing transplanting time, which comes around June 10. 5. The temperatures during the vegetative growth in Korea were higher than those temperatures that needed in the protein synthesis which ate the main metabolism during this stage. However, the temperatures at the time of reproductive growth was lower than the temperatures that needed in the sugar assimilation which is main metabolism in this stage. In this point of view, it might be considered that the proper time of growing rice plant in Korea would be rather earlier. 6. The temperatures and the day light conditions at the time of first tillering stage of rice plant, when planted as presenting transplanting practices, are very satisfactory, but the poor day light length, high temperatures and too wet conditions in the time of last-tillering stage(mid or last July) might cause the occurrence of disease such as blast. 7. The heading stage of rice plants at each region through nations when planted as presently practicing method comes when the day light length is short. 8. It was shown that the accumulated average air-temperature at the time of maturing stage was not enough and the heading time was too late, when considered the annual deviations of mean temperatures and low minimum temperatures. 9. The nitrogen content of each plant part at the each growing stage was very high at the stage of vegetative growth when compared with the nitrogen content at the stage of reproductive growth after heading. In this respect it was believed to be important to prevent the nutrient shortages at the reproductive stages, especially after the heading. 10. The area of unsatisfactory irrigation paddy fields and natural rain-fed paddy fields are getting reduced in Korea. The correlation between the rate of reducing unsatisfactory irrigation and natural rain-fed paddy fields and the rate of yield increase were computed. The correlation coefficients(r) between the area of unsatisfactory irrigation paddy fields and yield increase were +0.525, and between the natural rain-fed paddy fields and yield increase, +0.832 and between the unsatisfactory irrigation plus natural rain-fed paddy fields and yield increase, +0.84. And there were. highly significant positive correlations between natural rain-fed paddy fields and yield increases indicating that the less the area of natural rain-fed paddy fields, the greater the yields per unit area. 11. The results obtained from the fertilizer experiments (yield performance trials) conducted in both Korea and Japan showed that the yield of non-fertilized plots per 10 are was 231 kg in Korea and 360 kg in Japan. On the basis of this it might be concluded that the fertility of soil in Korea is lower than that in Japan. Furthermore it was. also found that the yields of non-nitrogen applied plots per 10 are were 236 kg in Korea and 383 kg in Japan. This also indicates that the yields of rice in Korea are largely depending on the nitrogen content in the soil. 12. The followings were obtained when the chemical natures of soils in both Korea and Japan were compared. (1) The content of organic matter, total nitrogen, exchangeable calcium, and magnesium in Korea were no more than the half those in Japan. (2) The content of N/2 chloride and soluble silicate in low-land soil were on the average lower in Korea. (3) The exchange capacity of bases in Korea was no more than half that in Japan. 13. It was also observed by comparing the soil nature of the soil with high yielding capacity with the soil with low yielding capacity that the exchange capacity of bases, exchangeable calcium and magnesium, potassium, phosphorus, manganese, silicate and iron were low in the soil with low yielding capacity. 14. The depth of furrow slice was always deeper in the soil with high yielding capacity, and the depth of furrow slice in Korea was also shallower than that in Japan. 15. Summarizing the various conditions mentioned previously and considering the effects of silicate and trace elements such as manganese and iron besides three elements on the physiological and plant type formation of rice crops, more realistic and more ideal fertilizing practices were proposed. proposed.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.17
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• pp.1-44
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• 1974

These studies were made at Suwon in 1972 and at Suwon, Iri, and Kwangju in 1973 to investigate grain filling process and variation of grain quality of NB 68513 and Caprock as hard red winter wheat, Suke ＃169 as soft red winter wheat variety and Yungkwang as semi-hard winter variety, grown under-three different fertilizer levels and seeding dates. Other experiments were conducted to find the effects of temperature, humidity and light intensity on the grain filling process and grain quality of Yungkwang and NB 68513 wheat varieties. These, experiments were conducted at Suwon in 1973 and 1974. 1. Grain filling process of wheat cultivars: 1) The frequency distribution of a grain weight shows that wider distribution of grain weight was associated with large grain groups rather than small grain group. In the large grain groups, the frequency was mostly concentrated near mean value, while the frequency was dispersed over the values in the small grain group. 2) The grain weight was more affected by the grain thickness and width than by grain length. 3) The grain weight during the ripening period was rapidly increased from 14 days after flowering to 35 days in Yungkwang and from 14 days after flowering to 28 days in NB 68513. The large grain group, Yungkwang was rather slowly increased and took a longer period in increase of endosperm ratio of grain than the small grain group, NB 68513. 4) In general, the 1, 000 grain weight was reduced under high temperature, low humidity, while it was increased under low temperature and high humidity condition, and under high temperature and humidity condition. The effect of shading on grain weight was greater in high temperature than in low temperature condition and no definite tendency was found in high humidity condition. 5) The effects of temperature, humidity and shading on 1, 000 grain weight were greater in large-grain group, Yungkwang than in small grain group, NB 68513. Highly significant positive correlation was found between 1, 000 grain weight and days to ripening. 6) The 1, 000 grain weight and test weight were increased more or less as the fertilizer levels applied were increased. However, the rate of increasing 1, 000 grain weight was low when fertilizer levels were increased from standard to double. The 1, 000 grain weight was high when planted early. Such tendency was greater in Suwon than in Kwangju or Iri area. 2. Milling quality: 7) The milling rate in a same group of varieties was higher under the condition of low temperature, high humidity and early maturing culture which were responsible for increasing 1, 000 grain weight. No definite relations were found along with locations. 8) In the varieties tested, the higher milling rate was found in large grain variety, Yungkwang, and the lowest milling rate was obtained from Suke ＃ 169, the small grain variety. But the small grained hard wheat variety such as Caprock and NB 68513 showed higher milling rate compared with the soft wheat variety, Suke ＃ 169. 9) There were no great differences of ash content due to location, fertilizer level and seeding date while remarkable differences due to variety were found. The ash content was high in the hard wheat varieties such as NB 68513, Caprock and low in soft wheat varieties such as Yungkwang and Suke ＃ 169. 3. Protein content: 10) The protein content was increased under the condition of high temperature, low humidity and shading, which were responsible for reduction of 1, 000 grain weight. The varietal differences of protein content due to high temperature, low humidity and shading conditions were greater in Yungkwang than in NB 68513. 11) The high content of protein in grain within one to two weeks after flowering might be due to the high ratio of pericarp and embryo to endosperm. As grains ripen, the effects of embryo and pericarp on protein content were decreased, reducing protein content. However, the protein content was getting increased from three or four weeks after flowering, and maximized at seven weeks after flowering. The protein content of grain at three to four weeks after flowering increased as the increase of 1, 000 grain weight. But the protein content of matured grain appeared to be affected by daily temperature on calender rather than by duration of ripening period. 12) Highly significant positive correlation value was found between the grain protein content and flour protein content. 13) The protein content was increased under the high level of fertilizers and late seeding. The local differences of protein content were greater in Suwon than in Kwangju and Iri. 14) Protein content in the varieties tested were high in Yungkwang, NB 68513 and Caprock, and low in Suke ＃ 169. However, variation in protein content due to the cultural methods was low in Suke ＃ 169. 15) Protein yield per unit area was increased in accordance with increase of fertilizer levels and early maturing culture. However, nitrogen fertilizer was utilized rather effectively in early maturing culture and Yungkwang was the highest in protein yield per unit area. 4. Physio-chemical properties of wheat flour: 16) Sedimentation value was higher under the conditions of high temperature, low humidity and high levels of fertilizers than under the conditions of low temperature, high moisture and low levels of fertilizers. Such differences of sedimentation values were more apparent in NB 68513 and Caprock than Yungkwang and Suke ＃ 169. The local difference of sedimentation value was greater in Suwon than in Kwangju and Iri. Even though the sedimentation value was highly correlated with protein content of grain, the high humidity was considered one of the factors affecting sedimentation value. 17) Changes of Pelshenke values due to the differences of cultural practices and locations were generally coincident with sedimentation values. 18) The mixing time required for mixogram was four to six minutes in NB 68513, five to seven minutes in Cap rock. The great variation of mixing time for Yungkwang and Suke ＃ 169 due to location and planting conditions was found. The mixing height and area were high in hard wheat than in soft wheat. Variation of protein content due to cultural methods were inconsistent. However, the pattern of mixogram were very much same regardless the treatments applied. With this regard, it could be concluded that the mixogram is a kind of method expressing the specific character of the variety. 19) Even though the milling property of NB 68513 and Caprock was deteriorated under either high temperature and low humidity of high fertilizer levels and late seeding conditions, baking quality was better due to improved physio-chemical properties of flour. In contrast, early maturing culture deteriorated physio-chemical properties, milling property of grain and grain protein yield per unit area was increased. However, it might be concluded that the hard wheat production of NB 68513 and Caprock for baking purpose could be done better in Suwon than in Iri or Kwangju area. 5. Interrelationships between the physio-chemical characters of wheat flour: 20) Physio-chemical properties of flour didn't have direct relationship with milling rate and ash content. Low grain weight produced high protein content and better physio-chemical flour properties. 21) In hard wheat varieties like NB 68513 and Caprock, protein content was significantly correlated with sedimentation value, Pelshenke value and mixing height. However, gluten strength and baking quality were improved by the increased protein content. In Yungkwang and Suk ＃ 169, protein content was correlated with sedimentation value, but no correlations were found with Pelshenke value and mixing height. Consequently, increase of protein content didn't improve the gluten strength in soft wheat. 22) The highly significant relationships between protein content and gluten strength and sedimentation . value, and between Pelshenke value, mixogram and gluten strength indicated that the determination of mixogram and Pelshenke value are useful for de terming soft and hard type of varieties. Determination of sedimentation value is considered useful method for quality evaluation of wheat grain under different cultural practices.

• Korean Journal of Food Science and Technology
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• v.36 no.3
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• pp.416-422
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• 2004

Efficacy of surface sterilization and physicochemical properties of electrolyzed water manufactured depending on electrolyte, materials, and type of electrolytic diaphragm used were investigated. Physical properties of electrolyzed water manufactured from diaphragm system showed the highest effectiveness under at distance between diaphragms of 1.0 mm and 20% NaCl supplying rate of 6 mL/min. ORP, HClO (should defined) content, and pH at above conditions were 1,170 mV, 100 ppm, and 2.5, respectively. Two-stage electrolyzed system was more effective than one-stage one. Electrolyzed water manufactured from non-diaphragm system at 4 mL/min supplying rate of 20% NaCl was similar to the most effective diaphragm system, whereas ORP, HClO content, and pH were 800 mV, 200 ppm, and 9, respectively. Sealed electrolyzed water could be preserved more than one month at room temperature with ORPs of 750 and 1,150 mV in non-diaphragm and diaphragm systems, respectively, and at HClO content of 100 ppm. Physicochemical properties of electrolyzed water manufactured from electrolytic diaphragm of $IrO_{2}$ and Pt+Ir were more effective than that of Pt. ORP and HClO contents of electrolyzed water manufactured from various electrolytes were high in order of NaCl>KCl>$CaCl_{2}$, whereas no differences were observed among electrolytes in sterilization efficacy. Twelve kinds of microorganisms tested (initial total count, $10^{5}-10^{6}CFU/mL$) were sterilized within 1-2 min by electrolyzed water.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.50 no.6
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• pp.428-434
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• 2005

For the purpose to verify the grain and evaluate milling properties of Korean waxy wheat, com­parison analysis between waxy wheat lines and their respective maternal parents were performed. The waxy lines showed various grain yields of 4.76${\~}$5.79 t/ha depending on parentages, which were corresponding to $80{\~}96\%$ levels of their respective maternal parents. One thousand grain weights of waxy lines were also lighter than its respective part in its parentage by exhibiting 32.8${\~}$34.6 g compared to 32.9${\~}$45.2 g of their parents. Test weights of waxy lines and their parents were 720${\~}$798 g/l and 786${\~}$797 g/l, respectively. The proportions of the grains above 2.5 mm in width were higher in order of Keumgang, Olgeuru, Geuru, SW97134, Suwon 292, Woori, SW97105, and SW97110. Waxy lines exhibited low milling properties by showing the straight flour yields ranging from $61.8\%$ to $67.1\%$ compared with the yields of their parents ranging from $66.1\%$ to $72.5\%$; the waxy lines were significantly lower in first break flour (Bl) and first reduction flour (Rl) yields in the Buller test mill, while significantly higher in the yields of second and third reduction flour (R2 and R3) than the respective ones of their parent wheat.