• School Mathematics
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• v.5 no.4
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• pp.507-520
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• 2003

본 연구는 실질적인 의미에서 학생들로 하여금 수학을 더 잘 이해할 수 있도록 돕기 위해 테크놀로지를 학교 교실에서 직접 활용하는 방안에 대한 연구이다. 특히 여기서는 수학을 가르치고 배우는 과정에서 가상학습체계가 주요한 도구로서 적용되었다. 내용은 무게중심을 택했고 12명의 중학생을 대상으로 현직교사가 직접 지도하였다. 학생들은 수업초기에 교사에 의해 소개되는 학생중심 학습활동에 강한 관심과 호기심을 보였고 집중력이 아주 강했다. 전통적인 수업방식과는 달리 학생들이 참여하였고 테크놀로지를 이용하여 전통적인 방식의 교실에서 할 수 없었던 수업의 시작은 학생들의 호기심을 자극하는데 충분하였다. 전반적으로 테크놀로지 환경에서의 수업을 선호하였지만 아직 전통적인 방식인 칠판과 분필을 이용한 수업을 선호한 학생들도 있었다. 새로운 변화도 좋지만 새로운 환경에 친화적이지 않거나 테크놀로지를 이용한 수업의 빠른 진행이 학생을 오히려 혼란하게 만들기도 하였다. 마지막으로 교사는 가상학습체계를 교실에서 활용함에 있어서 현 교육과정과 교과서를 크게 개혁하지 않아도 잘 준비되고 계획된 테크놀로지의 활용에 대한 잠재력을 확인할 수 있었다. 우리는 현재 테크놀로지의 보급에 비해 그 활용도가 낮다는 것을 잘 알고 있고 기타 입학시험이라는 현실이 교육과정과 학습방법의 개혁을 현실적으로 추진하는 것이 어려운 일임을 잘 알고 있다. 그래서 현 상황에서 테크놀로지의 사용을 가능하게 할 수 있는 방법을 모색하였다. 이미 보급된 테크놀로지와 교사와 학생의 테크놀로지에 대한 이해가 앞으로 그 잠재력을 갖고 있다고 확인하였다.보다 낮은 일반세균수 값을 보여주었다. 봄철 시료에 있어서 소규모 도계장은 본 냉각 후 도계과정을 제외하곤 모든 도계공정 단계에서 대규모 도계장보다 높은 일반 세균수의 측정값을 보여주었다. 봄철 시료의 냉각말기의 냉각수 일반세균수는 소규모 도계장이 대규모 도계장보다 높은 측정값을 보여주었다.주었다.다.㏖/s/$m^2$에서는 이앙후 각각 18일로 두 품종 모두 늦어, 약광은 유묘기에 분화되었던 분얼아를 휴면으로 유도할 수 있음을 시사하였다. 4. 유효경비율은 1220~220 $\mu$㏖/s/$m^2$에서 다산벼는 47~55%, 화성벼는 100~72%로 다산벼가 화성벼보다 낮았다. 이것은 다산벼는 무효분얼이 많다는 것을 시사하는 것으로 품종 육성시 유효경비율을 높여야 할 것이다.타났고, \circled2 회복상태에서, 10 lu$\chi$인 경우 서간에 1.26 $\mu\textrm{V}$, 야간에 1.59 $\mu\textrm{V}$였고, 100 lu$\chi$인 경우 서간에 2.63 $\mu\textrm{V}$ 야간에 3.65 $\mu\textrm{V}$였으며, 400 lu$\chi$인 경우 서간에 2.52 $\mu\textrm{V}$, 야간에 3.67 $\mu\textrm{V}$로 나타났다.히, 흉선, F냥, 비장 등의 림프구에 초기 세포용해성 감염을 일으키는데, B

• Horticultural Science & Technology
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• v.29 no.3
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• pp.273-277
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• 2011

Fusarium oxysporum f. sp. fragariae (Fof), the causal agent of crown and root rot in strawberry, is the most serious soilborne disease of nursery plants in Korea. The possibility of infection by Fof through runner propagation from infected mother plants of strawberry cv. 'Kumhyang' was assessed in stolons and daughter plants hanging from raised beds. The number of daughter plants from an infected mother plant in plastic house and photosynthetic photon flux (PPF) system, 280 ${\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ was 2.7 and 3.8 plants after 58 days, respectively. However, healthy mother plants produced 6.5 and 8.4 daughter plants, respectively. The pathogen was detected in the uppermost portion of the stolon after 58 days, but was not detected further down the stolon. After 90 days, it was detected in all portions of the stolon between mother and $1^{st}$ daughter plant and in 60% of all $1^{st}$ daughter plants. The pathogen was not detected in the corresponding portions of the non-infected controls. These results show that infected mother plants can transmit Fof to their daughter plants without passing through the soil and $1^{st}$ daughter was used as mother plant in PPF system for propagating healthy plants.

• Journal of Bio-Environment Control
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• v.29 no.3
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• pp.219-230
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• 2020

This study was conducted to determine the optimum medium and humidification period for the strawberry (Fragaria × ananassa Duch. cv. Maehyang) cutting seedling production. The cuttings were planted in coir (CO), rockwool (RW), phenolic foam (PF), and organic foam medium (OFM) with fogging treatment in 0, 3, 6, 9, or 12 days on February, 2019. And, as the field verification examination research, cuttings were planted in CO, RW, PF, and OFM, with misting treatment in 0, 6, 9, 12, or 15 days on June, 2019. In fogging treatments, rooting and survival rates of seedlings tended to increase with longer fogging periods, and rooting and survival rates were showed significantly higher in CO medium with more than 9 days of fogging periods. In misting treatments, rooting rate was significantly higher in CO and RW medium with more than 9 days of misting periods, and survival rate was significantly higher with more than 12 days of misting periods. There was no significantly difference by growth medium and humidification period in shoot and root growth. Therefore, when considering the rooting and survival rate the CO medium with 9 days of humidification period could be beneficial for the production of the 'Maehyang' strawberry cutting seedlings.

• Applied Biological Chemistry
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• v.18 no.2
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• pp.65-70
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• 1975

The cultivation of ginseng plant (Panax ginseng C.A. Meyer) in Korea as an eminent medicinal herb may be traced far back in history. However, the practices in cultivation have not much improved in terms of efficiency and scientific farming. In the present study some experiments were undertaken for the search of the soil and nutrition conditions, because of the nutritional requirement of ginseng plant shaws quite unique compared with other crops. In both the seed bed and the field 'Yakto' has been traditionally employed or the prime source of nutrition of the crop. Yakto is a complex matter prepared from raw foliage of the broad-leaved trees as the main portion with the admixture of a variety of organic nitrogen source through fermentative processes. The composition of Yakto may be classified coarsely into the decomposed and undecomposed substances, the former being further fractionated according their solubilities, comprising also various colloidal matters whose composition and structure are yet to be known. The Yakto-fractions were subjected to analyze for search of its nature and coarse composition in terms of the distribution of nitrogen, contents of organic functional groups such as -COOH, phenolic-OH, alcholic-OH and methoxyl and hydrolysable sugars. Furthermore, absorption-spectra of each fraction were determined in visible and infrared region and compared the results each other.

• Korean journal of applied entomology
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• v.49 no.4
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• pp.343-349
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• 2010

The golden apple snail was introduced to the Korea from Japan as a potential food for people in 1983. It is one of the pests of direct-seeded rice in korea. This study was conducted to investigate rice(Oriza sativa) consumption and the extent of damage by the golden apple snail(Pomacea canaliculata) in direct-sown paddy fields. Food consumption of the golden apple snail was highest at $30^{\circ}C$. When the emergence of the 1st, 3rd, and 5th leave of rice supplied food, the consumption of young(shell height 15mm) and adult golden apple snail(over shell height 30mm) at $30^{\circ}C$ were 19.0/79.8, 11.0/54.5, 5.5/18.5, and 0.0/2.0 individuals, respectively. Young rice seedings(before 5th leaves of rice) are very susceptible to golden apple snail damage because the young, tender leaves and stems favor the snail's feeding habits. The field experiment with four treatments (0, 2, 5 and 10 individuals respectively per 10 $m^2$) was carried out. The most serious yield loss was 16% from the plot with 10 adults released at emergency stage of rice.

• Journal of Bio-Environment Control
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• v.20 no.4
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• pp.283-289
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• 2011

This study was conducted to examine the effects of defoliation treatment on the growth and yield of strawberry ($Fragaria{\times}ananassa$ cv. Maehyang and Seolhyang) during nursery period. Leaves of strawberry plantlet had been removed except two, three and four fully expanded leaves until planting date. As the intensity of defoliation was strong, the petiole length was reduced and overgrowth of strawberry plantlet was suppressed. Outer diameter of crown in defoliation treatments significantly decreased but inner diameter of crown was not significant. Number of primary roots of the 3 leaves or 4 leaves defoliation treatment generally tended to increase, but there was not significantly different among treatments. Fresh weight and leaf area in the defoliation treatments significantly decreased and the root weight were higher in partial 3 leaves or 4 leaves defoliation treatment but was not significantly different among treatments. Because T/R ratio decreased significantly as growth inhibition of above-ground part compared to underground part, it is considered easy to take rooting after plantlet plating. As the intensity of defoliation was strong, chlorophyll contents tended to decrease significantly. Reduction of the endogenous nitrogen by defoliation effectively led to promote floral differentiation at low temperature and short day condition. This promoted timing of budding and flowering and also induced uniform flowering after plantlet planting. Marketable fruit yield of 3 leaves defoliation treatment tended to be higher than the control.

• Journal of Bio-Environment Control
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• v.20 no.4
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• pp.263-268
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• 2011

This study was carried out to investigate the effect of nursery period and block size on seedling quality and fruit yield of paprika (Capsicum annuum L. 'Cupra'). Seeds of paprika (Capsicum annuum L., Cupra) were sown in rockwool plugs. Seedlings were transferred and grown to the rockwool block different sizes: $5{\times}5$, $7.5{\times}7.5$ and $10{\times}10cm$ at sowing after 15 days. The plants were transplanted by 25, 30, 35, 40, 45 and 50 days we planted the seeds to the rockwool slabs. Seedling growth was not influenced by block size in the 25 day old plant, since then growed poorly with increasing nursery period in the $5{\times}5cm$ block size, plant height, stem diameter, fresh weight, dry weight have no difference from $10{\times}10cm$ and $7.5{\times}7.5cm$, but leaves and leaf area were higher $10{\times}10cm$ than the $7.5{\times}7.5cm$ block size. Growth of the paprika in field 80 days after sawing did not differ from nursery period and block size below 35 days old, but decreased with increasing nursery period and decreasing block size beyond 40 days old. Flowering did not differ from nursery period and block size below 35 days, but delayed with increasing nursery period and decreasing block size beyond 40 days old. The highest yield was obtained from 30 and 35 days old, and decreased with increasing nursery period and decreasing block size beyond 40 days old.

• Journal of Bio-Environment Control
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• v.21 no.4
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• pp.385-391
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• 2012

This study was conducted to investigate the effects of the runner cutting time on the growth and yield of strawberry (Fragaria ${\times}$ ananassa cv. Maehyang and Seolhyang) during nursery period of two consecutive years (2009 and 2010). Strawberry runners which connected from mother plants to daughter plants were cut 30, 20, 10 and 5 days before transplanting day (11 Sep. 2009 and 10 Sep. 2010). When runner cutting time delayed, more nutrition was supplied to the daughter plant until late nursery period. It showed that there was a tendency to increase the fresh weight, crown diameter and leaf chlorophyll content. On the other hand, when the runner was cut earlier, the growth of underground part such as root weight was improved. Irrigation demand increased to 29.7% in case of runner cutting from mother plant compared with runner non-cutting treatment. In addition, infection ratio of anthracnose through runner part was 37.6% higher in case of runner cutting than that of runner non-cutting treatment. After transplanting, budding and flowering period were delayed up to 2 or 3 days because of late runner cutting. But there was no significant difference in marketable fruit yield among runner cutting times. It is recommended to conduct runner cutting 5 or 10 days before transplanting for reducing the occurrence of anthracnose.

• Korean Journal of Medicinal Crop Science
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• v.4 no.1
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• pp.74-77
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• 1996

This experiment was conducted to evaluated the effect of CM (plant growth regulator) treatment on flowering, pod maturing and root yield components of Astragalus membramaceus Bunge. Three dilution rates (60, 70 and 80 times) were sprayed at $3{\sim}4$ leave stage. As the results, flowering was delayed $25{\sim}35$ days than August 13 of control and higher dilution rates was more effective to delay flowering. At the havesting time, be compared with non-treatment, plant height reduced $7.6{\sim}18.9\;cm$ and number of matured pods were decreased $50.6{\sim}76.1$ by increasing dilution rates. However, weight of dry root per plant was increased to 29% and dry root yield per 10a was increased to 28% in dilution rates 70 compared with non-treatment.

• Journal of Yeungnam Medical Science
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• v.12 no.2
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• pp.246-259
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• 1995

This study aimed to investigate the mechanism of action of baclofen on the detrusor muscle isolated from rat. Rats (Sprague-Dawley) were sacrificed by decapitation and exsanguination. Horizontal muscle strips of $2mm{\times}15mm$ were prepared for isometric myography in isolated muscle chamber bubbled with 95% / 5%-$O_2$ / $CO_2$ at $37^{\circ}C$, and the pH was maintained at 7.4. Detrusor strips contracted responding to the electrical field stimulation (EFS) by 2 Hz, 20 msec, monophasic square wave of 60 VDC. The initial peak of EFS-Induced contraction was tended to be suppresed by ${\alpha},{\beta}$-methylene-adenosine 5'-triphosphate (mATP), a partial agonist of purinergic receptor, and baclofen, a $GABA_B$ receptor agonist (statistically nonsignificant). The late sustained contraction by EFS was suppressed significantly (p < 0.05) by additions of atropione, a cholinergic muscarinic receptor antagonist and baclofen. The adenosine 5'-triphosphate-induced contraction was completely abolished by mA TP but not by baclofen. In the presence of atropine, the subsequent addition of acetylcholine could not contract the muscle strips: but the addition of acetylcholine in the presence of baclofen evoked a contraction to a remarkable extent. These results suggest that in the condition of present study, the cholinergic innervation may play a more important role than the purinergic one, and baclofen suppresses the contractility of rat detrusor by the stimulation of the $GABA_B$ receptors to inhibit the release of neurotransmitter from the cholinergic nerve ending.