• Journal of the Korea Society of Computer and Information
• /
• v.19 no.2
• /
• pp.183-191
• /
• 2014

In this study Cyclomatic Complexity of Web Software has been analyzed quantitatively by correlation between complexity and Number of Classes(NOC), and Number of Methods(NOM) which are object oriented programming measures. Based on the frequency distribution of complexity, NOC and NOM of software at the Web environment, correlation between complexity threshold and NOC threshold, and NOM threshold has been measured and more than 4,000 ASP files of 10 Web real projects have been used as the sample. The empirical result shows that NOC threshold is 21, NOM threshold is 40 and complexity threshold is 68 as high value, and 8 projects among of 10 except 2 projects with especially high frequency distribution shows that NOC threshold is 12, NOM threshold is 21 and complexity threshold is 52 with relatively low value, so correlation has been found out as exists. And also 8 projects with low threshold of complexity, NOC and NOM were internal management software, and the other 2 projects were external sales service software, Number of Classes and Number of Methods can be defined at the design stage according to business properties, and also the complexity can be estimated in order to improve the software quality.

• Journal of Korean Society of Coastal and Ocean Engineers
• /
• v.17 no.2
• /
• pp.80-85
• /
• 2005

This study, Using Pusan clay, examined a relationship between Dynamic and Static Liquid Tests. The Static Liquid Tests were carried out based on BS and JIS. The results of the study are summarized as follows. (1) The result of the Dynamic Liquid Limit Test showed that the liquid limit values of Natural condition soil were greater than those of oven-dried soil by $4\%\~15\%$. (2) The liquid limit value of the Static Liquid Limit Test was greater than that of the Dynamic Liquid Limit Test by $2\%\~9\%$. The following equations show the relationship between tile two values. WL, Fall(JIS)=0.961$\cdot$WL, Cas+4.209, WL, Fall(BS)=0.969$\cdot$WL, Cas+5.024, (3) The liquid limit value of BS was greater than that of JIS by $1\%\~6\%$. The following equation shows the relationship between the two values. WL, Fall(BS)=0.976WL, Fall(JIS)+2.638.

• Proceedings of the Korea Water Resources Association Conference
• /
• 2021.06a
• /
• pp.310-310
• /
• 2021

지난 수년간 하천 인근에서 홍수로 인하여 다양한 피해가 발생하고 있다. 이러한 홍수피해를 경감하기위해 구조적 비구조적 대책들을 세우고 있으며, 중요한 비구조적 대책 중의 하나가 홍수경보시스템을 구축하는 것이다. 일반적으로 홍수경보시스템을 구축하기 위하여 홍수경보기준지점의 수위를 설정하며 이에 대응하는 한계유량을 산출하고 GIUH 강우-유출모형을 통하여 한계유량에 대응하는 경보강수량을 산정하는 방식을 택하고 있다. 특히 한계유량을 산출하는 경우, 다양한 연구에서 Manning 공식을 통하여 한계유량을 산출하고 있다. 이에 대한 적정성을 비교하기 위해 본 연구에서는 HEC-RAS모형을 통하여 한계유량을 계산하였고 Manning식에서 나온 값과 비교하였다. 비교결과 Manning식에서 산출된 한계유량은 과다한 경보 강수량 값을 채택하고 기존 설계강수량에 비해 매우 큰 값임을 확인할 수 있었다. 이에 비해 HEC-RAS의 한계 유량값은 적정한 경보강수량 값을 제시하였고 연평균알람기준에도 적정함을 알 수 있었다. 본 연구 결과를 통해, 현재 다양한 하천사업이 이루어져 대부분의 하천의 측량이 이루어진 상황에서 기존의 Manning식에 의한 한계유량 산출보다는 HEC-RAS를 통하여 한계유량을 산정해야하는 것이 보다 적정해 보인다.

• Journal of IKEEE
• /
• v.25 no.4
• /
• pp.584-590
• /
• 2021

This paper proposes a removal method of signal interference between ultrasound sensors where ghost signals due to interference are excluded and correct signal is recognized in distance mensurement using ultrasound sensors. The proposed method detects and excludes ghost signals when previous measured distance is compared to current measured distance and the distance difference exceeds a threshold. The threshold is fixed in conventional methods, so ghost signals cannot be correctly excluded when ultrasound sensor or target object move rapidly. On the contrary, to improve accuracy, the threshold is not fixed in the proposed method, and the threshold is adpatively determined based on the relative velocity when ultrasound sensor or target object move. Experiments of distance measurement with ultrasound signal interference are carried out where multiple ultrasound sensors of same type are exploited with maximum interference, and the results show that the proposed method efficiently exclude ghost signals.

• Journal of the Korea Society of Computer and Information
• /
• v.17 no.6
• /
• pp.153-161
• /
• 2012

In this empirical study at the Web environment based on the frequency distribution of the cyclomatic complexity number of the application, the relevance of the threshold has been analyzed with the next two assumptions. The upper bound established by McCabe in the procedural programming equals 10 and the upper bound established by Lopez in the Java programming equals 5. Which numerical value can be adapted to Web application contexts? In order to answer this 10 web site projects have been collected and a sample of more than 4,000 ASP files has been measured. After analyzing the frequency distribution of the cyclomatic complexity of the Web application, experiment result is that more than 90% of Web application have a complexity less than 50 and also 50 is proposed as threshold of Web application. Web application has the complex architecture with Server, Client and HTML, and the HTML side has the high complexity 35~40. The reason of high complexity is that HTML program is usually made of menu type for home page or site map, and the relevance of that has been explained. In the near future we need to find out if there exist some hidden properties of the Web application architecture related to complexity.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.21 no.10
• /
• pp.13-21
• /
• 2007

Based on the measurement results, a limit value for the change of the brightness of the headlamp, and an estimation algorithm considering the driver's safety was developed. Limitation values concerning being uncomfortable, blinking, and brightness change were indicated based on a subjective estimation of the psychological estimation. Also a safety estimation algorithm and a limitation value for stopping safely without the threat of obstacles to the vehicle were indicated by the perception measurement.

• Proceedings of the KIEE Conference
• /
• 2006.11a
• /
• pp.258-260
• /
• 2006

비수도권과 수도권의 수급 불균형 해소를 위한 6개의 북상선로에 흐르는 융통조류량의 한계값이 경제성 평가의 한 기준이 될 수 있다. 본 논문에서는 수도권 융통전력 한계를 고려한 제약급전사례의 검토 결과를 이용하여 FACTS 투입에 따른 증대된 융통전력한계를 바탕으로 FACTS 투입에 따른 혼잡비용측면에서 운전이익을 평가하는 방법을 논한다. 즉, F-V 해석결과를 이용하여, 수도권 융통전력 한계값을 결정하고 좀 더 정확한 운전이익 계산하기 위하여 결정된 한계값을 P-POOL 프로그램을 이용하여 혼잡비용 경감 효과를 확인할 수 있는 모의 방법을 확립한다. 확립된 방안은 계획계통을 이용해 검증하고, 최종적으로 FACTS 투입량과 투입후보지에 대한 융통전력 한계 측면에서의 경제성 평가한다.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
• /
• 2006.05a
• /
• pp.131-136
• /
• 2006

전조등의 밝기 변동에 대한 운전자의 시인성 및 뇌파측정, 심리평가를 행하고 이를 바탕으로 전조등 밝기변화의 한계값과 운전자의 안전성을 고려한 평가 알고리즘을 개발하였다. 전조등의 밝기 변화 한계치는 심리평가의 설문지 작성을 통한 주관적 평가를 바탕으로 밝기 변화, 눈 깜박임, 불쾌감 등에 대한 한계값을 제시하였다. 그리고 뇌파측정을 바탕으로 정신적, 시각적 스트레스에 대한 한계값을 제시하였으며, 운전자의 시인성 측정을 바탕으로 차량을 장애물의 위협 없이 안전하게 정지하기 위한 한계값을 제시하였다. 안전성 평가 알고리즘은 장애물을 인식하고 브레이크 페달을 밟기 시작하기 까지 최대한 허용할 수 있는 시간인, 여유 시간 이내에 전압변동을 완료하고 최초의 정상 전압으로 복귀하는 경우와 그렇지 않은 경우를 적용할 수 있는 2종류의 알고리즘을 개발하였다.

• Nuclear Engineering and Technology
• /
• v.21 no.1
• /
• pp.32-39
• /
• 1989

A method for determining the optimum ideal MHD $\beta$limit and the operation conditions is presented for an axisymmetric tokamak reactor with a circular cross section. The $\beta$limit is calculated under the constraints of ideal MHD instability criteria with varying the operation conditions which depend on the toroidal current density distributions. Semiempirical laws deduced from experimental observations are used for the toroidal current density distributions. Analytic derivations of various equations required to determine the $\beta$limit are carried out from the empirical equations. Various distributions of the $\beta$limit are obtained by the numerical calculations for different distributions of the toroidal current density. The resulting values of the maximum $\beta$limited by ideal MHD instabilities are expressed by a scaling law in terms of the tokamak geometry and the safety factor.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.34 no.6
• /
• pp.1695-1705
• /
• 2014

In the present study, a total of 275 tested specimens (149 of non-seismically designed and 126 of seismically designed) for reinforced concrete bridge piers with circular section have been investigated in order to suggest drift limits probabilistically according to damage states in seismic fragility analysis. Thus, quantitative damage states of the piers have been evaluated depending on details of the piers. Nonlinear time-history analyses have been conducted for a damaged bridge in terms of using the suggested drift limits. Then, seismic fragility analysis for a reinforced concrete bridge structure has been conducted using both suggested and existing drift limits. Comparative analyses have revealed that median values by the suggested limits is smaller than those by the existing limits. This implies that seismic performance of the structure can be overestimated when the existing limits are used.