• 한국전자통신학회논문지
• /
• 제15권6호
• /
• pp.1023-1030
• /
• 2020

임의의 그래프 신호를 복원하기 위해 그래프상의 일부 노드로 구성된 샘플링 집합내의 노드들의 신호값만을 사용하게 되는 경우, 이를 위한 최적의 샘플링 집합 선택 문제에 대해 연구한다. 고도의 계산량을 요구하는 고유값 분해 (eigen decomposition)를 사용하지 않고, 노드를 선택하는 과정에서의 신호 변화값의 차이를 비용함수로 제시한다. 구체적으로, 기존 방식의 비용함수인 신호 복원오차를 최소화하는 대신에 본 연구에서는 신호 변화값의 차이를 비용함수로 채택하여 이를 최소화하는 간단하고 고속의 탐욕 (greedy) 샘플링 집합선택 알고리즘을 제안한다. 기존의 고속알고리즘과 성능평가 비교를 위해 다양한 그래프 신호에 대한 폭넓은 실험을 진행하여, 기존 방식 대비 신호복원 성능감소를 약 7% 이내로 유지하면서 실행시간을 10배이상으로 단축하였음을 보인다.

• 대한기계학회논문집A
• /
• 제25권8호
• /
• pp.1173-1182
• /
• 2001

Recent noticeable advances of CNC machine tools have considerably improved productivity and precision in manufacturing processes. However, in the respect of productivity some defects still remain because selection of machining conditions entirely depends on the experiences of programmers. Usually, machining conditions such as feed rate and spindle speed have been selected conservatively by considering the worst cases, and it has brought the loss of machining efficiency. Thus, the improvement of cutting force controller has been done to regulate cutting force constantly and to maximize feedrate simultaneously in case that machining conditions change variously. In this study, sliding mode control with boundary layer is applied to milling process for cutting force regulation and in a commercial CNC machining center data transfer between PC and PMC (programmable machine controller) of CNC machine is done using a standard interface method. And in the cutting force measurement, an indirect cutting force measuring system using current signal of AC servo is adopted in order not to use high-priced equipment like tool dynamometer. The purpose of this study is to maximize the productivity in milling process, thus its results can be applied to cases such as rough cutting process.

• 복식
• /
• 제54권1호
• /
• pp.53-68
• /
• 2004

The purposes of this study were to classify the contents of lifestyle of adolescence consumers, to examine the differences of lifestyle, importance of store attribute, preference of fashion store according to demographic variables, to test preference of fashion store and lifestyle, preference of fashion store, and to examine how the preference of fashion store was influenced by lifestyle, importance of store attribute, and demographic variables. Subjects were 317 adolescence consumers(13-24 years) in Seoul, Korea. Preference of imported & brand goods, orientation of fashion & beauty life, and family orientation had a direct effect on preference of department store($R^2$=.129). Sex had an indirect effect on preference of department store through orientation of fashion & beauty life. Search of video media & information and age(-) had a direct effect on preference of entertainment shopping center($R^2$=.150). Orientation of fashion & beauty life(-), sales promotion, sex, and reasonable consumption had a direct effect on preference of discount store(R =$^2$.109). Sex(-) had an indirect discount store through orientation of fashion & beauty life, and sex(-), search of video media & information, age(-), and reasonable consumption did through sales promotion. Sales promotion, preference of imported & brand goods(-), and store atmosphere(-) had a direct effect on preference of traditional market($R^2$=.060). Sex(-), age(-), search of video media & information, and reasonable consumption had an indirect effect on preference of traditional market through sales promotion, and search of video media & information, reasonal consumption, and acceptance of foreign culture did through store atmosphere.

• 한국작물학회지
• /
• 제35권1호
• /
• pp.90-96
• /
• 1990

본 연구는 담배육종에 있어 유용형질이 담배 수량에 영향을 미치는 직접 및 간접효과들을 잡종초기세대에 분석함으로써 앞으로의 선발육종에 대한 기초정보를 얻기 위하여 수행하였다. 시험방법은 유전적 특성이 다양한 8개 품종을 공시하여 이면교잡을 하고 양성된 F$_1$, F$_2$ 각 세대별 28개 조합을 Orient 및 Burley 종 각 재배법에 따라 1986년부터 1988년까지 본 연구소 대구시험장에서 수행하였다. 조사항목은 초장, 엽수, 엽장, 엽폭, 개화일수 및 수량 등 6개 농업형질과 nicotine, total nitrogen, protein nitrogen, total volatile base, pet. ether extract 등 6개의 내용성분들로서 얻어진 결과는 다음과 같다. 1. 각 형질들의 수량에 대한 직접효과는 세대나 재배법에 따라 다소의 차이는 있었지만 대개 엽장, 엽폭, 개화일수 및 엽수의 순으로 높았으나 내용성분은 낮았다. 2. 간접효과는 재배법이나 세대에 관계없이 대개 엽장, 개화일수, 그리고 total nitrogen의 형질들이 타형질에 미치는 영향이 컸었다.

• 한국산림과학회지
• /
• 제82권2호
• /
• pp.122-127
• /
• 1993

본(本) 연구(硏究)는 옻나무의 칠액생산(漆液生産)을 증대(增大)시키기 위한 육종계획(育種計劃)의 일환으로 산칠량(産漆量)이 많은 옻나무 개체선발(個體選拔)에 관여하는 여러가지 형질(形質)들의 규명 및 옻나무의 간접선발(間接選拔) 가능성을 알아보기 위하여 수행되었다. 임의로 선정된 24본의 표본목을 대상으로 생장인자(生長因子) 및 수피형질(樹皮形質)과 수피내(樹皮內) 옻산함량과의 상관분석을 한 결과 수피의 옻산함량은 외피(外皮)두께 및 칠액구(漆液構)의 수(數)와는 1%, 내피(內皮)두께와는 5% 수준의 유의상관을 나타내어 수피두께와 단위면적당 칠액구(漆液溝) 수(數)가 산칠량(産漆量)이 많은 옻나무의 간접선발(間接選拔) 기준이 될 수 있음을 시사하였다. 800여본(本)의 선발(選拔) 대상목 중 수피의 옻산함량에 의거하여 옻산함량이 가장 높은 16개체(個體)를 산칠량(産漆量)이 많은 선발목(選拔木)으로 최종 선발(選拔)하였다. 선발목(選拔木)들은 임의로 선정된 표본목들에 비해 수피가 두껍고 수피의 2차 사부조직내(篩部組織內) 칠액구(漆液溝)의 수(數)가 많으며 칠액구(漆液溝)의 크기가 크고 고르게 발달하고 있음을 관찰할 수 있었다.

• Journal of Biosystems Engineering
• /
• 제30권1호
• /
• pp.45-55
• /
• 2005

Knowledge of the relationship between crop yield and yield-limiting factors is essential for precision farming. However, developing this knowledge is not easy because these yield-limiting factors are interrelated and affect crop yield in different ways. In this study, data for grain yield and yield-limiting factors, including crop chlorophyll content, soil chemical properties, and topography were collected for a small (0.3 ha) rice paddy field in Korea and a large (36 ha) upland corn field in the USA, and relationships were investigated with path analysis. Using this approach, the effects of limiting factors on crop yield could be separated into direct effects and indirect effects acting through other factors. Path analysis provided more insight into these complex relationships than did simple correlation or multiple linear regression analysis. Results of correlation analysis for the rice paddy field showed that EC, Ca, and $SiO_2$ had significant (P<0.1) correlations with rice yield, while pH, Ca, Mg, Na, $SiO_2,\;and\;P_2O_5$ had significant correlations with the SPAD chlorophyll reading. Path analysis provided additional information about the importance and contribution paths of soil variables to rice yield and growth. Ca had the highest direct effect (0.52) and indirect effect via Mg (-0.37) on rice yield. The indirect effect of Mg through Ca (0.51) was higher than the direct effect (-0.38). Path analysis also enabled more appropriate selection of important factors limiting crop yield by considering cause-and-effect relationships among predictor and response variables. For example, although pH showed a positive correlation (r=0.35) with SPAD readings, the correlation was mainly due to the indirect positive effects acting through Mg and $SiO_2$, while pH not only showed negative direct effects, but also negatively impacted indirect effects of other variables on SPAD readings. For the large upland Missouri corn field, two topographic factors, elevation and slope, had significant (P<0.1) direct effects on yield and highly significant (P<0.01) correlations with other limiting factors. Based on the correlation analysis alone, P and K were determined to be nutrients that would increase corn yield for this field. With the help of path analysis, however, increases in Mg could also be expected to increase corn yield in this case. In general, path analysis results were consistent with published optimum ranges of nutrients for rice and com production. We conclude that path analysis can be a useful tool to investigate interrelationships between crop yield and yield limiting factors on a site-specific basis.

• Journal of Animal Science and Technology
• /
• 제45권3호
• /
• pp.343-354
• /
• 2003

고급육형 한우개량을 위하여 현행 실시하고 있는 한우 후대검정에서 조사되는 배장근단면적, 등지방두께 및 근내지방도 등에 대한 유전적 개량량과 초음파 측정장치를 이용한 해당 형질들의 육질판정자료에 의한 간접선발시 유전적 개량량을 모의실험을 통하여 추정하고 상호 그 효율성을 비교하였다. 본 연구에 적용된 Monte Carlo 모의실험은 각 설정 모형별, 표현형 선발 및 다형질 BLUP 추정방법에 의한 육종가 추정치에 의한 선발을 적용하여 각각 10반복씩 반복 실험하였다. 각 모형별 모의실험방법은 종축집단의 크기 및 세대 수 그리고 설정모형을 동일하게 설계하였으며 수컷 100두와 암컷 2,000두의 기초집단으로부터 매 세대 수컷 20두와 암컷 1,000두를 3가지 형질에 동일한 가중치를 두어 10세대 동안 선발하였다. 최종 생성된 자료를 이용하여 유전적 개량량을 추정하였고 이를 각 모형별, 선발방법별로 비교, 분석하였다. 분석결과 현행 실시하고 있는 한우 후대검정과 유사한 모의실험에서의 각 형질별 육종가 추정치에 의한 선발시 유전적 개량량과 비교한 결과, 초음파 측정치와 도축 실측치 간의 유전상관을 0.81-0.97으로 가정하고 암, 수 모두 초음파 측정자료를 조사한다는 가정으로 초음파 측정치의 육종가에 의한 선발을 실시할 때, 1.66${\sim}$2.44 배의 개량 효율성이 있는 것으로 추정되었으며 이들 상관을 0.63${\sim}$0.68으로 가정한 모의실험에서는 1.18${\sim}$2.08 배의 개량 효율성이 있는 것으로 추정되었다. 따라서 고급육형 한우개량을 위한 초음파 측정치를 이용한 검정방법을 활용하고 이를 이용한 종축선발을 실시할 때 개량효율을 크게 향상시킬 수 있을 것으로 사료되었다. 반면에 각 형질별 개량효율성을 살펴보면 개량효율성이 가장 낮은 형질은 근내지방도로써 이는 표현형 변이가 상대적으로 낮은 형질에 선발의 가중치를 동일하게 가정한 것에 기인된 것으로 사료되며 따라서 근내지방도의 변이를 크게 할 수 있는 자료조사방법의 변경, 또는 선발의 가중치를 높이는 방법에 대한 연구가 필요할 것으로 사료되었다.

• Asian-Australasian Journal of Animal Sciences
• /
• 제24권10호
• /
• pp.1335-1340
• /
• 2011

Different genetic parameters for weaning weight and wool traits were estimated using restricted maximum likelihood (REML) in Angora rabbits. Total wool yield of first (I), second (II) and third (III) clips were taken as a separate trait under study. The records from more than 2,700 animals were analysed through fitting six animal models with various combinations of direct and maternal effects. A log likelihood ratio test was used to select the most appropriate model for each trait. Direct heritability estimates for the wool traits were found to be moderate to high across different models. Heritability estimates obtained from the best model were 0.24, 0.22, 0.20 and 0.21 for weaning weight, clip I, II and III; respectively. Maternal effects especially due to permanent environment had higher importance at clip I and found to be declining in subsequent clips. The estimates of repeatability of doe effect on wool traits were 0.44, 0.26 and 0.18 for clip I, II and III; respectively. Weaning weight had moderately high genetic correlations with clip I (0.57) and II (0.45), but very low (0.11) with clip III. Results indicated that genetic improvement for wool yield in Angora rabbit is possible through direct selection. Further, weaning weight could be considered as desirable trait for earliest indirect selection for wool yield in view of its high genetic correlation with wool traits.

• Nutrition Research and Practice
• /
• 제12권4호
• /
• pp.348-354
• /
• 2018

BACKGROUND/OBJECTIVES: Obesity is a serious concern worldwide, for which the restaurant industry holds partial responsibility. This study was conducted to estimate restaurant consumers' intention to select healthy menu items and to examine the relationships among behavioral beliefs, past behaviors, attitudes and behavioral intentions, which are known to be major determinants of consumer behaviors. SUBJECTS/METHODS: An online, self-administered survey was distributed for data collection. The study sample consisted of customers who reported having visited casual dining restaurants in the last three months at the time of the survey. Structural equation modeling was used to verify the fit of the proposed research model. RESULTS: Structural equation modeling revealed that the proposed model supports the sequential, mediated (indirect) relationships among behavioral beliefs, past behaviors, attitudes and behavioral intentions toward healthy menu selection. CONCLUSION: This study contributes to the available literature regarding obesity by adding past behaviors, one of the most influential variables involved in prediction of future behaviors of consumers, to the TPB model, enabling a better understanding of restaurant consumers' rational decision process regarding healthy menu choices. The results of this study provide practical implications for restaurant practitioners and government agencies regarding ways to promote healthy menus.

• 대한간호학회지
• /
• 제47권4호
• /
• pp.488-498
• /
• 2017

Purpose: The focus of the study was on the selection-optimization-compensation (SOC) strategy to predict successful aging mediated by dyspnea symptoms in older adults with chronic obstructive pulmonary disease. The model was constructed based on the hypotheses that coping strategy and social support of the elders predict successful aging through the SOC strategies. Methods: Participants were 218 outpatients with chronic obstructive pulmonary disease recruited for the study. Data collection was done from March 25 to September 11, 2015, and analyzed using SPSSWIN 22.0 and AMOS 21.0. Results: The hypothetical model appeared to be fit to the data. Seven of eight hypotheses selected for hypothetical model were statistically significant. The SOC strategy has only significant indirect effects through dyspnea symptoms on successful aging. Coping strategy, social support, SOC strategies and dyspnea symptoms explained 62% of variance in successful aging. Conclusion: The SOC strategies with social support and dyspnea symptoms significantly explained successful aging among patients with chronic obstructive pulmonary disease. Nursing strategies should be focused on social support and coping strategies to optimize SOC strategies so that older adults with chronic obstructive pulmonary disease are able to manage dyspnea symptoms and eventually achieve successful aging.