• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.22 no.10
• /
• pp.2165-2170
• /
• 1997

In this paepr, the distortion effects of impairments in CDMA transmitter system were analyzed. We considered not only linear distortion effects, for example, I/Q imbalance, quadrature offset and carrier leakage, but also nonlinear distortion effects such as AM-AM and AM-PM noise in power amplifier. To investigate how the impariments impact on the performance of CDMA transmitter, all effects represented as a function of CDMA modulation quality which is an important measure of the transmitted signal. These results show the limitation value of each impairment which is required to satisfy the IS-95 standard.

• Analytical Science and Technology
• /
• v.20 no.1
• /
• pp.70-77
• /
• 2007

Twelve chlorophenols (CPs) were extracted by liquid phase microextraction (LPME) from the industrial waste-water and analyzed by GC/MS. To establish the optimal conditions, species of extraction solvent, sample amount, pH of sample, salting out effect, a number of sampling and plunger movement speed were investigated. As a result, the linearities of calibaration curves ranged from 0.9913 to 0.9999, while LODs and LOQs were from 0.05 to 10.0 ng/mL except 2,3,4,5-tetrachlorophenol and pentachlorophenol. Using this method, 4-chloro-3-methylphenol confirmed from waste water at the concentration of 784 ng/mL. The method can be applicable to detect chlorophenols from industrial waste-water.

• The Journal of the Korea Contents Association
• /
• v.14 no.11
• /
• pp.743-758
• /
• 2014

The purpose of this study is to examine the mediating effect of economic stress in the relationship between Perceived Income Inequality and Suicidal Ideation among old adults. To achieve this objective, this study analyzed basic statistics, reliability, correlation, and regression (tolerance and variance inflation factor) with the help of SPSS ver. 18.0. using data of 532 elderlies over 65 years old who live in Jeollanam-do. The main study results were as follows. The result shows the significant medicating effect of economic stress in the relationship between Income Inequality and Suicidal Ideation. Based on these results, political and practical implications are proposed.

• Proceedings of the Korea Technology Innovation Society Conference
• /
• 2017.11a
• /
• pp.387-412
• /
• 2017

우리나라의 중소기업은 국가경제의 근간을 이루고 있으며, 고용창출, 기술혁신, 산업의 다양성 등 여러 측면에서 국민경제 발전에 있어서 실질적인 원동력이 되고 있다. 이로 인해 중소기업은 기술혁신을 통해서 혁신역량을 확보하는 것이 더욱더 중요해졌으며, 내부자원의 한계로 인해 경영에 필요한 다양한 정보와 여러 가지 도움들을 외부와의 협업과 다양한 네트워크 활동을 통해 습득해 나가고 있다. 더 나아가서 시장기회를 포착하고 조직 성장을 위한 수단들을 모색하기 위한 수단으로 기업가 정신 또한 필요하다. 본 연구는 ICT중소기업의 기업성과에 영향을 미치는 요인에 있어 기업가 정신과 기업의 혁신역량이 어떠한 영향을 미치는지 알아보고자 했으며, 사회적 자본이 기업가 정신과 기업성과 간의 조절역할을 하는지 살펴보고자 1,200개 기업을 대상으로 실증 분석을 했다. 분석 결과를 요약하면 다음과 같다. 첫째, 기업가 정신은 기업성과에 유의미한 영향을 미치는 것으로 확인됐으며, 사회적 자본 변수가 기업가 정신과 기업성과 간의 조절효과가 있다는 것을 확인할 수 있었다. 둘째, 혁신 역량이 기업성과에 유의미한 영향을 미치는 것으로 나타났으며, 또한 사회적 자본 변수가 조절효과를 한다는 것을 확인할 수 있었다. 이러한 연구 결과를 통해, 기업가 정신이 기업성과에 영향을 미치는데 있어서 사회적 자본이 중요한 역할을 하고 있다는 것을 확인할 수 있었다.

• Analytical Science and Technology
• /
• v.14 no.6
• /
• pp.486-493
• /
• 2001

The effect of SIMS analysis conditions such as mesh grid, offset voltage and ion species on the in-depth profile for bismuth titanate thin film was examined in terms of charging effect and detection limit. The results shows that the use of offset voltage -40 V reduces the charging effect and the detection limit. The employment of mesh grid in sample preparation leads to the reduction of the charging effect in small amount, but deteriorate the detection limit. Utilization of primary $O^-$ ion for SIMS analysis of bismuth titanate thin film showed almost the same effect as using offset voltage -40 V. However, it takes approximately triple acquisition time than using $O_2{^+}$ ion due to the poor beam current of the source in the experiment.

• 한국방재학회:학술대회논문집
• /
• 2011.02a
• /
• pp.85-85
• /
• 2011

기존 과속단속카메라의 한계와 더불어 차량의 속도 거동이 더욱 순화될 필요가 제기됨에 따라 국내에서는 2007년 12월 16일 영동고속도로 둔내터널에서 처음 구간과속단속시스템을 도입하였다. 현재 고속국도 6개소를 포함하여 총 8개소에서 구간과속단속시스템을 운영하고 있다. 하지만 해당 시스템의 도입효과가 명확하지 않아 시스템의 효과에 대한 의문도 꾸준히 제기되고 있다. 본 연구에서는 미국 Los Alamos연구에서 개발된 TRANSIMS(TRansportation Analysis and SIMulation System)의 시뮬레이션 결과를 이용해 시스템 적용 전 후의 거시적 교통류 특성을 수집하여 효과에 대하여 분석하였다. 본 연구에서는 구간과속단속시스템의 효과를 분석하기 임의의 네트워크를 제작하여 모의실험을 해 보았다. 네트워크는 총 연장 12km의 직선형 구간으로 제작하였다. 모의실험에 사용되는 링크의 Cell크기는 3m로 설정하여 TRANSIMS의 내정값인 7.5m보다 더욱 상세한 결과가 나오도록 설정하였다. 링크는 편도 3차로로 설정하여 모의실험을 실시하였으며, 구간단속이 미치는 영향을 실제와 유사하게 적용하기위해 모의실험을 하는 링크의 제한속도를 구간단속 실시 전에는 160km/h, 실시 후에는 100km/h로 설정하였다. 구간단속 실시 전 링크의 제한속도를 160km/h로 높게 설정한 것은 실제 통행이 발생하는 속도를 구현하기위해서이며, 차종별 최대 속도를 제한하여 속도분포를 나타내었다. TRANSIMS를 통한 구간과속단속시스템의 효과를 분석하는 모의실험 결과 그림 1의 그래프에서 나타나는 것과 같이 구간단속 전 후에서 속도저감효과가 나타나는 것을 확인 할 수 있었다. 특히, 교통류율이 낮을 때 속도가 높게 나타나던 부분이 구간단속 실시 후 속도가 낮아지는 것을 보아 실제로 교통류율이 낮은 고속국도에서는 높은 효과를 기대할 수 있다고 판단된다. 표 1에서 구간단속 전 후의 주행차량의 속도변화를 살펴보면 과속운행의 비율이 상당히 주는 것을 확인할 수 있다. 이러한 특성 때문에 교통량이 비교적 적은 고속국도에서는 뛰어난 효과를 발휘할 것이라고 예상된다.

• Journal of Energy Engineering
• /
• v.11 no.4
• /
• pp.317-323
• /
• 2002

This paper proposed the calculation method of the generation operating avoided cost to cost-effectiveness evaluation of energy conservation programs that compounded the Proxy Plant Method and Load Decrement Method. This method introduced an operating index of the Energy Efficiency Demand-Side Management (EEDSM) resources based on the end-user's behaviors on the electricity power usage. The operation index is applied to calculate the hourly operating capacity of diffused high-efficiency appliances. And the operating capacity on the peak load hours for reference load is computed through the reduction of the peak load that contributes to that hour. Also, the proposed method evaluated the effect of EEDSM resources. The IEEE-RTS is adopted as a sample system to analyze impacts of an EEDSM. This paper, we have analyzed the effect of EEDSM upon the changes in the generation of generator, generation cost and the system marginal price (SMP). This method can be used to evaluate the impact of the diffused DSM resource and to estimate the impact in short-term EEDSM program. Further, result of the calculation can be utilized to pabulum for effect analysis of EEDSM resources.

• Journal of the Korean Geographical Society
• /
• v.38 no.6
• /
• pp.906-921
• /
• 2003

This paper discusses the price effects of local growth controls on the housing markets of California jurisdictions in the late 1980s empirically. Particularly, based on spatial econometric modeling, the study focuses on the homebuilding constrained by growth controls which is one of the price effects. The modeling produces the California-wide generalizable results, differentiates among the individual effects of various growth controls on homebuilding, and covers spatial effects. Thereby, this study intends to supplement the existing work on the price effects of growth controls. The modeling results find that restrictive residential zoning had the effect of significantly restricting housing construction in the late 1980s. On the other hand, urban growth boundaries had the effect of accommodating homebuilding. Population growth or housing permit caps and adequate public facility ordinances had no significant effects on housing construction.

• The Korean Journal of Applied Statistics
• /
• v.28 no.2
• /
• pp.289-294
• /
• 2015

Linear mixed models are commonly used in the clinical pharmaceutical studies to analyze repeated measures such as the crossover study data of bioequivalence studies. In these models, random effects describe the correlation between repeated outcomes and variance-covariance matrix explain within-subject variabilities. Bioequivalence analysis verifies whether a 90% confidence interval for geometric mean ratio of Cmax and AUC between reference drug and test drug is included in the bioequivalence margin [0.8, 1.25] performed using linear mixed models with period, sequence and treatment effects as fixed and sequence nested subject effects as random. A Levofloxacin study is referred to for an example of real data analysis.

• Korean Security Journal
• /
• no.56
• /
• pp.9-30
• /
• 2018

Crime prevention strategies are introduced to reduce the loss caused by crimes, and Target hardening against domestic burglary attacks is broadly accepted as one of such physical security strategies. In terms of business and home security, target hardening is one of the suite of protective measures that are included in crime prevention through environmental design(CPTED). This can include ensuring all doors and windows are sourced and fitted in such a way that they can resist forcible and surreptitious from the attack of intruder. Target hardening with certified security doors, security windows and secure locks are revealed to be much more effective to deter burglary attacks than other security devices, such as CCTV, lightings and alarms which have largely psychological and indirect impact. A pilot program of target hardening utilizing certified security window and locks was carried out in Ansan city, South Korea in 2016. This study is based on the quasi-experimental design of this program for a residential area. The researchers tried to verify the crime displacement effect of the target hardening program and the diffusion effects of crime prevention benefits by analysing the crime statistics. The evaluation utilized WDQ(Weighted Displacement Quotient) technique to analyze whether the crime displacement occurred, compared the crime statistics of the experimental area with that of buffer zone and controlled areas. The result showed that the target hardening program was significantly effective in crime prevention. The number of burglary in the experimental site with target hardening intervention reduced by 100%, although the areas without the intervention showed reduction in the burglary. The crime displacement was not found at all, and the number of burlary at the buffer zone also reduced significantly.