• KOREAN JOURNAL OF CROP SCIENCE
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• v.32 no.4
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• pp.436-442
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• 1987

The variations of the anther and pistil length of some rice cultivars at the different planting density and fertility levels were tested and their inheritance mode was studied. The anther length of a spikelet on a secondary panicle branch was longer than the one of a spikelet on a primary panicle branch. In the cultivar Z97B, both the anther and the pistil length were increased slightly along the increased plant-ing spacings, But, in the cultivar IR43 no general tendency was observed. The fertilizer levels applied n the field did not affect both the anther and pistil length of a given cultivar. In a cross of IR56/IR8, the anther length showed continuous variation with longer anther being recessive in the F2 population. While, the pistil length showed a continuous variation with longer pistil being over-dominance. In all of the crosses which IR56 involved, the general and specific combining abilities were high for both the anther and pistil length. The broad sense heritability for anther length was 0.46, and for pistil length was 0.88. The correlation coefficients of anther length and pistil length were 0.33 for phenotypic and 0.44 for geno-typic.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.29 no.6
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• pp.539-545
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• 2016

UPS system in the liquefied natural gas(LNG) receiving terminal is one of the fundamental equipment that need to sustain operation during earthquake. In this study, modal identification test of UPS system was performed based on IEEE Std. 693-2005 and natural frequencies and modal damping, mode shapes had been identified. In addition, tri-axial time history test was performed to check the behavior and stress of the equipment during earthquake. Eigenvalue analysis was performed and analysis model was modified by reflecting the results of the test. Static analysis by dead weight and response spectrum analysis were performed to compare the combined stresses with the stress results of test. Dynamic characteristics and combined stresses under seismic load condition of the improved analysis model were similar to the test results and in this regard the compatibility was proved.

• Composites Research
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• v.36 no.1
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• pp.25-31
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• 2023

Composite structures have been designed by stacking the laminae with different stacking angles to meet the required mechanical performance. Although the induced stresses on the composite structures under the external loads usually differ depending on the location, we determined the stacking sequence based on the maximum stress, which leads to low efficiency and generally is not the optimum design. Recently, piecewise integrated composites (PICs) were suggested for solving this inefficiency. PICs assume the perfect bonding between adjacent pieces, but this is ideal and hard to accomplish. Therefore, the overlap at the boundary is essential to prevent separation from each other. In this study, we investigated the effect of the overlap design on the impact failure mode of PIC plates. We fabricated the sample composite plates with different overlap designs using the fast curing carbon prepreg and conducted the impact tests according to ASTM D 7136. We found that PICs had different failure modes according to the overlap design, which lead the changes of absorbed impact energies as well as impact load curves.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.5 no.1
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• pp.51-56
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• 1969

Fourty lines of F4 progenies of an Adzuki bean cross, Jukdoo (Korean local variety) X Nesumimochi (Japanese variety) were used as the material, and these lines were grown in replicated trials in 1967. Phenotypic, genotypic and environmental covariances among all possible traits of eight character are calculated as shown in table 1. Phenotypic, genotypic and environmental correlations among all possible paris of eight characters were calculated as shown in table 2. In general, genotypic correlations were higher than the corresponding phenotypic corresponding phenotypic correlations. The genotypic correlations between seed yield (grain weight per plot) and oter agronomic characters indicated that seed yield was genetically associated with the character of pod number per plant, and grain number per plant, which is closely correlated with pod number pr plant, are affected more in Adzukl bean yield than the other agronomic characteracters.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.38 no.3
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• pp.295-302
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• 2014

An internal gear pump is required to improve the flow rate and noise. Furthermore, such pumps are durable and small in size. In this study, equations of the rotor shape with multiple profiles (ellipse 1-involute-ellipse 2) were derived, and relevant performance parameters (pressure angle, irregularity, and specific sliding) of the internal gear pump to noise were predicted and compared. Rotor profiles and performance parameters were obtained by a prediction algorithm for theoretical analysis, and the effects between the design parameters and the performance parameters were analyzed. Based on the analysis results of the effects, an optimal design of the rotor profile was proposed, and a noise test of the prototype was performed to evaluate the reliability of the design.

• Journal of the Korean Society for Nondestructive Testing
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• v.34 no.5
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• pp.369-376
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• 2014

This paper presents a method that integrates passive and active-sensing techniques for the structural health monitoring of plate-like structures. Three piezoelectric transducers are deployed in a L-shape to detect and locate an impact event by measuring and processing the acoustic emission data. The same sensor arrays are used to estimate the subsequent structural damage using guided waves. Because this method does not require a prior knowledge of the structural parameters, such as the wave velocity profile in various directions, accurate results could be achieved even on anisotropic or curved plates. A series of experiments was performed on plates, including a spar-wing structure, to demonstrate the capability of the proposed method. The performance was also compared to that of traditional approaches and the superior capability of the proposed method was experimentally demonstrated.

• 한국방재학회:학술대회논문집
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• 2011.02a
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• pp.54-54
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• 2011

기존의 착저식 방파제를 보완하기 위하여 부유식 방파제가 개발되었고, 많은 연구가 선행되어 왔다. 부유식 방파제의 최대 장점은 경제성과 친환경성이다. 그러나 부유식 방파제는 소파성능이 떨어진다는 단점이 있으며, 이를 개선하기 위해 잠재와 혼용, 배열형에 관한 연구등이 선행되어왔다. 그러나 이것은 경제성이라는 강점을 고려하지 못하였다. 그래서 본 연구에서는 부유식 방파제의 중요한 장점중 하나인 경제성을 고려해, 단면현상 변화만을 이용하여 부유식 방파제의 소파성능 개선하고자 하였다. RANS(Reynolds averaged Navier-Stokes) 방정식에 기초하여 VOF법과 $k-{\varepsilon}$ 난류모델을 결합한 수치모델인 CADMAS-SURF를 이용하였으며, 구조물 단면형상 변화를 이용해 와의 상호 간섭을 유도하였고, 이에 따른 투과율 변화를 관찰 하였다. 결과를 살펴보면 요철1 단면에서는 구조물 전면 하단부분과 구조물 후면 하단부분에서 와의 간섭이 일어났으며 가장 아래 요철 부분에서 유속의 전달현상이 보인다. 투과계수는 일반적인 부유식 방파제와 마찬가지로 L/B가 1~4사이 값인, 비교적 단주기에서는 0.3~0.4의 투과율을 보였으나 L/B가 5를 넘어가면서 0.45~0.55의 투과율을 보였고, 요철2 단면에서는 전면과 후면에서 발달한 와가 전, 후면 돌출부에 의해 바닥까지 전파되지 못하는 양상을 보였으며, 돌출부 사이 중앙부분에서 가장 활발한 와의 간섭을 관찰 할 수 있었다. 돌출부 아래에서 역시 강력한 와의 간섭을 보이고 있다. 투과율 역시 가장 낮은 값을 보였으며 비교적 단주기 구간인 B/L 1~4 에서는 0.2~0.35 사이의 값을 가졌으며 5~10사이구간에서는 0.35~0.34의 값을 보이고 있다. 이 같은 결과는 와의 간섭이 가장 활발하게 나타난 결과로 보인다. 그리고 요철 3단면에서는 전면 돌출부 끝단에서의 활발한 와의 간섭을 관찰 할 수 있었다. 투과율은 세 단면 중 가장 높은 값의 투과율을 보이지만 B/L 3~4 구간에서 요철1 경우보다 낮은 값의 투과율을 보이고 있다. 결과에서 보듯이 도출부의 적절한 조합과 배치를 통해 언급한 연구목표(와의 생성과 간섭, 방파효율 개선)를 달성하였고 추후에 돌출부의 크기와 배치, 흘수의 영향, 수심의 영향 등을 고려한 연구가 진행된다면 더욱 우수한 단면형상을 개발 할 것이라 예상된다.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.29 no.2
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• pp.113-121
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• 2011

In this paper, we proposed the method automatically to match areal feature based on similarity using spatial information. For this, we extracted candidate matching pairs intersected between two different spatial datasets, and then measured a shape similarity, which is calculated by an weight sum method of each matching criterion automatically derived from CRITIC method. In this time, matching pairs were selected when similarity is more than a threshold determined by outliers detection of adjusted boxplot from training data. After applying this method to two distinct spatial datasets: a digital topographic map and street-name address base map, we conformed that buildings were matched, that shape is similar and a large area is overlaid in visual evaluation, and F-Measure is highly 0.932 in statistical evaluation.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.6
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• pp.2457-2462
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• 2011

The need for rapid and accurate measurement of 3-dimensional objects is increasing due to the paradigmatic shift in manufacturing from mass production to small batch production. A three dimensional measurement technique which can provide the dimensional information of the object manufactured or to be manufactured has been developed. This method is based on phase shifting moire topology. Digital-Micromirror-Device (DMD) has been used in generating phase shifting moire fringes. And the mechanically moving optical components used for phase shifting, which might result in measurement errors, have been replaced by the DMD. Inherent $2\pi$-ambiguity problem, occurring in the calculation of phase from the light intensity distribution due to the nature of arctangent function, has been overcome by adapting the phase unwrapping method. The advantage of this technique is the easy change of the range and the resolution of the measurement by simply changing the computer generated grid pattern with the appropriate combination of projection lens of various focal length.

• Journal of Bio-Environment Control
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• v.7 no.4
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• pp.290-297
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• 1998

In this study an optimization of greenhouse roof shape was performed to maximize solar light transmission which is one of the most important elements in greenhouse environment. To determine roof shape that maximize the total light transmissivity, a computer model for analysing light transmissivity was composed and the Genetic Algorithms was applied for solving optimization problems. By setting composite model as objective function(fitness function), the optimum combination of design variables(roof inclination angle, width ratio) was searched using Genetic Algorithms. The optimum combination of input variables for the maximum light transmissivity at Suwon in winter was found 40 degree root angle , 0.5 width ratio, for two span greenhouses and 37 $_。 / roof angle, 0.7 width ratio, for single span greenhouses.es.