• Proceedings of the Korea Information Processing Society Conference
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• 2006.05a
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• pp.261-264
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• 2006

소프트웨어 개발 후 인도 전 테스트 단계중에 발생되는 테스트 노력 소요량을 고려한 소프트웨어 신뢰도 성장 모델을 제시하여 테스트 노력소요량 동태를 시간함수인 로지스틱 곡선으로 설명한다. 그러므로, 본 논문에서는 로지스틱 테스트노력 곡선이 소프트웨어의 개발/테스트 노력곡선으로 적절하게 표현될 수 있다는 것과 실제 데이터를 근거로 하여 적용하여서 예측성이 매우 좋은 능력을 가지고 있다는 것을 보이고자 한다.

• The Korean Journal of Malacology
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• v.15 no.1
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• pp.41-47
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• 1999

From September 1994 to April 1996, we observed the suspending time dependant meat increase (dry weight) for oysters at Pukman Bay in Korea. The oysters which suspended in September increased to 5 g in meat weight (dry weight) by January. Ones in June increased rapidly but lessened during summer and this stagnation of meat increase extended to autumn. It took long time to compensate for the loss of meat weight owing to spawning. Oysters suspended in July or August showed low growth or stagnation due to the high water temperature and spawning activities after suspending. However, meat weight showed sudden increasement after December and achieved 5 g at the late farm period. The meat increase of oysters suspended in October or November was very slow during entire growing period. Most of them did not achieved 5 g during farm period. The negative correlation was observed between meat growth and water temperature in September. Also, there was a high correlation between meat growth and chlorophyll-a. It was believed that deficiency of food organisms in the water column lead slow growth in terms of meat growth, particularly right after transplanting seed oysters to the farm. Our study suggests that proper time for transplanting oysters is between August and mid-September. However, the data indicate that good growth of oysters is depending upon amount of food available in the water column.

• International Area Studies Review
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• v.13 no.3
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• pp.269-286
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• 2009

The aim of the paper is to study environmental impacts of openness and trade in korea, and analyze the relationships between trade, development and environment. This study established endogenous determinants such as inflow FDI, level of environmental pollution and economic growth, and assumed a proposition that each individual variables are in two-way relationships among the three key variables such as the openness, the environment and GDP. To estimate a system of equations, a simultaneous equation model is used because the simultaneity problems are formidable. The results show that the more openness and economic growth increase, the more level of environmental quality improve. This study also found that FDI and openness, and economic growth bring along the level of environmental quality.

• Journal of Animal Science and Technology
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• v.44 no.2
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• pp.165-170
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• 2002

Mature weight (A) and rate of maturing (k) estimated by nonlinear regression were studied to determine the optimum age range over which the estimate of growth curve parameters can be estimated. The weight-age data from 1,133 Hanwoo bulls at Hanwoo Improvement Center of N.A.C.F. were used to fit the growth curve using Gompertz model. All available weight data from birth to the specific age of months were used for the estimation of parameters: the six specific ages used were 12, 14, 16, 18, 20 22 and 24 months of age. The mean estimates of mature weight (A) were 966.5, 1,255.9, 1,126.2, 916.5, 842.2, 780.9 and 767.0kg for ages 12 through 24 months, respectively. The mean estimates of mature weight (A) to 22 and 24 months of age were not different from each other. However, they were different from the estimates based on the data to other ages. Mean estimates of rate of maturing (k) were 3.362, 3.595, 3.536, 3.421, 3.403, 3.409 and 3.411 for ages 12 through 24 months, respectively. The mean estimates of maturing rate (k) for ages 18 through 24 months of age were not significantly different from each other. However, they were different from the estimates based on the data to other ages. Correlations among estimates of A at various ages showed the highest value of 0.93 between 22 and 24 months. Correlations among estimates of k at various ages were highest ranging from 0.91 to 0.99 among 18 to 24 months. The correlations between A and k were positive and tended to decrease with the increase of the age from 0.84 for the age of 12 months to 0.10 for the age of 24 months. Thus, the estimates of growth curve parameters, A and k, suitable for genetic studies can be derived from accumulated Hanwoo bulls after 22 months of age.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2012.10a
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• pp.953-954
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• 2012

• Journal of Korean Society of Industrial and Systems Engineering
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• v.17 no.32
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• pp.73-79
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• 1994

본 연구는 관리한계설정을 위한 새로운 방법을 제시한다. 일반적 관리한계는 중심선(Central Line)과 표준편차(Standard Deviation)에 기인한다. 그러나 본 연구에서는 제품수명주기(PLC)의 각 단계상 발생되는 손익분기점(Break-even Point)과 한계이익곡선 특성을 통하여 탄력적 관리한계(Elastic Control Limit : ECL)를 구축하고자 하였다. 탄력적 관리한계와 한계이익곡선의 관계에서 중심선은 최대이익, $3{sigma}$한계는 최대이익점과 가장 근접해 있는 (상위/하위)손익분기점까지의 거리로 파악할 수 있다. 그리고 총 변동은 ｛상위손익분기점(UBEP) - 하위손익분기점(LBEP)｝으로 고려할 수 있다. 전개 과정으로서는 1. 각 제품별 수명주기(PLC)를 각 단계별로 구분한다. 2. 각 단계별 총이익곡선(TRC)과 총비용곡선(TCC)을 구한다. 3. 한계이익곡선상의 최대이익지점을 구한다. 이러한 연구는 제품성장단계별 평균과 분산의 변동을 동시에 고려하여 탄력적 관리가 가능하다는 장점이 있다. 나아가 마케팅과 소비자 행동의 분석으로 확대될 수 있다.

• Journal of the Korean Institute of Telematics and Electronics
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• v.25 no.11
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• pp.1329-1334
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• 1988

A new method was developed for growing oxidation film by thermal reaction of $NH_3$ and $O_2$. The growth rate increased with the increase of partial pressure of $NH_3$. Optical transparency of the growth film was 12% at the wave number 1100 $cm^{-1}$ compared with 17% by thermal dry oxidation method, and the quality was much better. In C-V characteristic curve, $Q_{OX}$ was almost equal to $Q_{SS}$ and no hysteresis phenomena was observed. n-MOS transistors fabricated with this new method showed $I_D$-$V_{DS}$ characteristics better than thermal dry oxidation method.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.24 no.12A
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• pp.2025-2033
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• 1999

In this paper, we forecast launching time of the commercial IMT-2000 service as feb. 2001, according to expert’s opinion, and most of they forecast rapid evolution. And, we propose two different models according to two cases for competition power of price for IMT-2000 service subscriber demand forecasting. In this paper, we combine the expert’s opinion method with the growth curve model for demand forecasting for new products in order to reduce error of the demand forecasting that haven’t past references. The estimation of needed coefficients for each growth curve model is based on experts’ subjective opinions.

• Journal of the Korean Data and Information Science Society
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• v.25 no.6
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• pp.1481-1489
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• 2014

For predicting yearly total attendances in Korean probaseball games, ARIMA models have been widely adopted so far. In this paper, we discuss two other ways of ARIMAX and growth curves with an exogenous variable to predict the attendances. By using the exogenous variable, it turns out that the prediction has been improved compared to ARIMA. It is concluded that various statistical methods must be considered for better prediction, and its results can be applied to predict the attendances of other pro sports.

• Transactions of the Korean Society of Mechanical Engineers
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• v.13 no.5
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• pp.928-937
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• 1989

Applicability of $T_{\delta}$ proposed by Shin et al as an instability parameter for ductile material is investigated, Both general fracture test and instability fracture test are performed using compact tension specimens of structural alloy steel(SCM4), The values of ( $T_{\delta}$)$_{app}$(applied tearing modules) estimated from the real load vs. crack growth curve measured from experiments are compared with those estimated from the limit load vs. crack growth curve. The results are:(1) the $T_{\delta}$ parameter may be used as a crack instability parameter:(2) the use of ( $T_{\delta}$)$_{app}$ estimated from the load-crack growth curve, proposed in this study is reasonably justified.ified.d.