• 한국수학교육학회지시리즈B:순수및응용수학
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• 제25권2호
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• pp.95-113
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• 2018

A mathematical knot is an embedded circle in ${\mathbb{R}}^3$. A fundamental problem in knot theory is classifying knots up to its numbers of crossing points. Knots are often distinguished by using a knot invariant, a quantity which is the same for equivalent knots. Knot polynomials are one of well known knot invariants. In 2006, J. Przytycki showed the effects of a n - move (a local change in a knot diagram) on several knot polynomials. In this paper, the authors review about knot polynomials, especially Jones polynomial, and give an alternative proof to a part of the Przytychi's result for the case n = 3 on the Jones polynomial.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1994년도 추계학술대회 논문집
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• pp.866-871
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• 1994

B-spline curves and surfaces are effective solutions for design and modelling of the freeform models. The control methods of these are using with control points, knot vectors and weight of NURBS. Using control point is easy and resonable for representation of general models. But the movement of control points bring out the reformation of original convex hull. The B-splines with nonuniform knot vector provide good result of the shape modification without convex hull reforming. B-splines are constructed with control points and basis functions. Nonuniform knot vectors effect on the basis functions. And the blending curves describe the prorities of knot vectors. Applying of these, users will forecast of the reformed curves after modifying controllabler primitives.

• 한국유기농업학회지
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• 제19권spc호
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• pp.267-270
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• 2011

Root-knot nematodes cause a significant damage on fruit yield and quality of green house growing crops. To asses the effect of eggplant rootstock, Torvum vigor', TaibyouVF' and 'Daitaro' were grafted on eggplants(Solanum melongena cv. Chookyang) and planted in root-knot nematode infested microplot in green house and compared their fruit yield, quality and plant growth with non-grafted control. Eggplant grafted with Torvum vigor had the highest fruit yield and top growth and followed by Daitaro. Non-grafted eggplant had lower yield but had higher root weight because of heavy root-knot nematode infection. Rootstock grafting in eggplant farming is a good alternative technique in root-knot nematode infested green houses without compromising fruit yield and can be applied instantly as organic farming practice.

• International Journal of Industrial Entomology and Biomaterials
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• 제8권2호
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• pp.175-179
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• 2004

Trichoderma harzianum-THN1 parasitising the egg masses of root knot nematode Meloidogyne incognita was isolated from galled mulberry roots and evaluated for its potential to control root knot disease. In pot experiments root galling was reduced and leaf yield increased significantly following soil treatment with T. harzianum-THN1. The extracts obtained from the soils inoculated with T. harzianum-THN1 drastically inhibited the hatching of nematode eggs and the effect was irreversible even after the eggs were transferred to fresh water. The fungus was equally effective in controlling the disease in nematode infested mulberry garden under field conditions which was significant over the most commonly used egg parasitic fungus Paecilomyces lilacinus. The disease reduction recorded with T. harzianum was on par with the plants treated with the nematicide Carbofuran. The results suggest that T. harzianum- THN1 could be used as a potent ecofriendly biocontrol agent against M. incognita in mulberry without any residual toxicity to silkworms. T. harzianum- THN1 can form an important component of integrated disease management package in mulberry cultivation.

• 한국응용곤충학회지
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• 제20권4호
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• pp.223-227
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• 1981

These experiments were conducted to investigate the nematicidal effects of the insecticides, Mocap(O-Ethyl-S, S-dipropyl phosphorodithioate), Carbofuran(2,3-Dihydro-2,2-dimethyl benzofuranyl ethyl carbamate), Terbufos (S-tert-buthylthio methyl O,O-diethyl phosphordithioate) and their mixtures (Mocap+carbofuran, Mocap+Terbufos, Carbofuran+Terbufos) on growth of 2year-old ginseng, Panax ginseng C.A. Meyer, and the control of root-knot nematodes. There was no evidence of plant injury from insecticide treatment of ginseng, although the rate of emergence of the treated ginseng was slightly inhibited. The insecticide treatments showed no of-flavor of ginseng plant. Terbufos and Mocap provided heifer confrol of the root-knot nematodes than carbofuran alone and their mixtures. Mixtures of the insecticides showed antagonisitic effect to the root-knot nematodes.

• 한국유기농업학회지
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• 제19권spc호
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• pp.255-258
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• 2011

When kiwifruit root system infected with nematodes was treated by hot water dipping treatment, the maximum temperature for this treatment was suggested as $50^{\circ}C$. The lowest killing temperature of internal root-knot in the root tissue was $48^{\circ}C$. Consequently, root-knot nematodes could be killed without damaging root tissues by the hot water dipping treatment at $48^{\circ}C$ for 10 minutes. This could be useful for organic production and distribution of kiwifruit seedlings by avoiding the synthetic nematicides which are not easily decomposed in soil once applied.

• 대한관절경학회지
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• 제8권1호
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• pp.37-44
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• 2004

목적: 잠김(Locking)이 가능한 이동 매듭의 (sliding knot) 최적 매듭 유지력 (knot-holdingcapacity KHC)을 가지기 위한 추가적인 반 매듭의 (additional half-hitches) 개수를 알아보고자 하였다. 대상 및 방법: 4가지의 관절경적 이동 매듭법 (Duncan매듭법, Field 매듭법, Giant매듭법, SMC매듭법)을 대상으로 매듭 유지력을 실험하였다. 각각의 매듭을 만들기 위해 처음의 이동 매듭과 추가적인 5개의 반 매듭으로 구성된 6개의 연속적인 매듭을 만들었다. 각각의 추가된 반 매듭은 서로 교차하며 매듭의 지대 (post)도 교차하여 매는 방식으로 (reversing half-hitches with alternate posts, RHAPS) 하였다. 각각의 연속적인 매듭을 구성하기위해 No.2 Ethibond봉합사를 이용하여 각각의 매듭 형태에 12개의 매듭을 만들었다. 매듭의 인장 및 유지력 실험은 servohydraulic material testing system(Instron 8511, MTS, Minneapolis, MN)으로 주기적 부하(cyclic loading)를 시켜, 임상적으로 실패라 규정한 3 mm의 전위가 생길 때까지의 부하 (load to clinical failure). 매듭이 완전히 실패했을 때의 부하 강도 (load to ultimate failure), 그리고 실패 형태 (mode of failure)를 측정하였다. 결과: 추가적인 반 매듭이 없는 최초의 이동 매듭 자체로는 대부분 주기적 부하에 의해 매듭의 실패를 보였다. 주기적 부하 검사에서 각각의 추가적인 반 매듭이 증가할수록 평균 전위 값은 감소하였다. SMC 매듭법과 Giant 매듭법은 하나의 추가적인 반 매듭 이후로 0.1 mm이하의 전위 값을 보였고 Field와 Duncan 매듭법은 3개의 추가 반매듭이 필요하였다. SMC 매듭법과 Duncan 매듭법은 80 N을 견디기 위해 단 하나의 추가 반 매듭이 필요하였고, Field와 Giant 매듭법은 2개의 추가 반 매듭이 필요하였다. 100 N이상의 부하를 견디기 위해서는 SMC 매듭법은 3개의 추가 반 매듭이 필요하였고, 다른 3가지의 매듭법은 4개의 추가 반 매듭이 필요하였다. 추가 반 매듭이 증가함에 따라 봉합사는 풀리는 것보다 끊어지는 양상을 보였다. Duncan매듭법은 5개의 추가 반 매듭 이후에도 풀림현상을 보였고, 다른 3개의 매듭법은 3개의 추가 반 매듭 이후엔 75%이상이 봉합사의 풀림 현상보다는 끊어지는 양상을 보였다. (SMC, Field 매듭법은 92%, Ciant 매듭법은 75%)결론: 어떤 매듭법이라도 이동 매듭법 만으로는 주기적 부하 검사를 견디지 못했다. 모든 종류의 실험에서 SMC 매듭법은 최소2개의 두개의 추가 반 매듭이 필요하였다. Duncan 매듭법은 최적 매듭 유지력을 위해 3개 이상의 추가 반 매듭이 필요하였다. 모든 매듭법에서 3개나 그 이상의 추가 반 매듭이 최적 유지력에서 정점에 가까운 양상을 보였다.

• The Plant Pathology Journal
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• 제25권2호
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• pp.189-192
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• 2009

The effect of plant extracts of eucalyptus (Eucalyptus chamadulonsis), garlic (Allium sativium), marigold (Tagetes erecta) and neem (Azadirachta indica) and essential oils were tested on the suppression of root-knot nematode Meloidogyne incognita under greenhouse and field conditions. In vitro study, all tested treatments had nematicidal effect on nematode juveniles after 24 and 48 hours from exposures. The highest percentage of nematode mortality was achieved by application of neem extract (65.4%), essential oils (64.4%) and marigold extract (60.5%), followed by garlic and eucalyptus extracts (38.7-39.5%). Under greenhouse and field conditions, neem extract and essential oils treatments were more effective in reducing population numbers of the M. incognita in soil and root gall index compared to other treatments. In field experiments, the maximum protection of tomato plant against root-knot nematode was obtained by application of neem and essential oil treatments, 44.2 and 32.6%, respectively.

• 한국미생물·생명공학회지
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• 제22권6호
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• pp.679-684
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• 1994

For a biological control of root-knot nematode (Meloidogyne incognita) in tomato, efficiency of Bacillus thuringiensis subsp. indiana strain TH109 (BtTH109) on the nematode control was investigated. After the mixture of strain BtTH109 and wheat bran was treated into rhizosphere of the tomato plants with nematode eggs, the stem height and root growth of plants increased. And the juveniles and eggs of nematode are not found in both roots of tomatoes and pot soil after cultured broth of the strain BtTH109 treated 4 times at 3 day-interval into rhizosphere of the infected tomatoes.

• 농약과학회지
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• 제20권1호
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• pp.47-55
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• 2016

본 연구는 커피박 퇴비와 벨벳콩 식물체 분말 처리에 따른 고구마뿌리혹선충 살충효과를 평가하였다. 커피박 퇴비와 벨벳콩 식물체 분말 처리중, 1% 벨벳콩 식물체 분말 처리가 뿌리혹선충의 살충율이 83.2%로 가장 높게 나타났다. 또한 실내에서 호피무늬 벨벳콩 추출물 농도별로 처리한 시간의 경과에 따라 뿌리혹선충 유충의 치사율이 증가하였다. 호피무늬 벨벳콩 추출물 처리 24시간 후, 1.2%와 2.4% 농도에서 뿌리혹선충 유충의 치사율이 가장 높게 나타났다. 커피박 퇴비와 벨벳콩 식물체 분말 처리가 호박유묘의 생육에 미치는 영향을 조사하였더니 20% 커피박 퇴비 처리구는 호박 유묘의 생육을 억제하였으나 1% 호피무늬 벨벳콩 분말 처리구가 호박 유묘의 생육촉진효과가 가장 뛰어났다. 하지만 유기성 자원인 벨벳콩과 커피박 퇴비를 이용하여 유기농 호박 재배토양에서 발생하는 고구마뿌리혹선충을 효과적으로 방제하기 위한 재료로 사용하기 위해서는 처리농도와 방법에 대한 추가적인 연구가 필요할 것으로 생각한다.