• 한국해양공학회:학술대회논문집
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• 한국해양공학회 2003년도 춘계학술대회 논문집
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• pp.27-31
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• 2003

Underwater acoustic navigation systems are classified into three systems: ultra-short baseline (USBL), short baseline (SBL), and long baseline (LBL). Because the USBL system estimates the angle of a submersible, the estimation error becomes large if the submersible is far from the USBL transducer array mounted under a support vessel. SBL and LBL systems estimate submersible's location more accurately because they have wider distribution of measuring sensors. Especially LBL systems are widely used as a navigation system for deep ocean applications. Although it is most accurate system it still has estimation errors because of noise, measurement error, refraction and multi-path of acoustic signal, or wrong information of the distributed transponders. In this paper the estimation error of the LBL system are analyzed from a point of sensitivity. It is assumed that the error exists only in the distance between a submersible and the transponders. For this purpose sensitivity of the estimated position with respect to relative distances between them is analyzed. The result says that estimation error is small if the submersible is close to transponders but not near the ocean bottom.

• Asian Pacific Journal of Cancer Prevention
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• 제14권1호
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• pp.293-297
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• 2013

Background: : Chemotherapy-induced thrombocytopenia (CIT) is an important cause of morbitity in patients with cancer. Aim: To investigate the effect of the baseline plasma D-dimer level, an important marker for thrombotic activity, on chemotherapy-induced thrombocytopenia in patients with stage III colon cancer. Materials and Methods: A total of 43 (28 men) eligible patients were divided into two groups according to whether they exhibited chemotherapy-induced thrombocytopenia: Group 1 (n=21) and Group 2 (n=22). Comparison was made using demographic, histopathologic, and laboratory variables. Additionally, baseline plasma D-dimer levels underwent receiver operation characteristics curve analysis, and areas under the curve were calculated. Sensitivity, specificity, and positive and negative likelihood rates were then determined. Results: The incidence of chemotherapy-induced thrombocytopenia had a significant correlation with baseline platelet count (r=0.568, P=0.031) and baseline plasma D-dimer levels (r=0.617, P=0.036). When the cut-off point for the latter was set as 498 ng/mL, the area under the curve was 0.89 (95%CI: 0.74-0.93), the sensitivity was 91.4%, the specificity was 89.7%, the positive likelihood rate was 3.64 and the negative likelihood rate was 0.24 for chemotherapy-induced thrombocytopenia diagnosis. Conclusions: The baseline level of plasma D-dimer could help to differentiate high-risk patients for chemotherapy-induced thrombocytopenia.

• International Journal of Aeronautical and Space Sciences
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• 제16권1호
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• pp.89-101
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• 2015

To satisfy civil aviation requirements using the Global Navigation Satellite System (GNSS), it is important to guarantee system integrity. In this work, we propose a fault detection algorithm for GNSS ephemeris anomalies. The basic principle concerns baseline length estimation with GNSS measurements (pseudorange, broadcasted ephemerides). The estimated baseline length is subtracted from the true baseline length, computed using the exact surveyed ground antenna positions. If this subtracted value differs by more than a given threshold, this indicates that an ephemeris anomaly has been detected. This algorithm is suitable for detecting Type A ephemeris failure, and more advantageous for use with multiple stations with various long baseline vectors. The principles of the algorithm, sensitivity analysis, minimum detectable error (MDE), and protection level derivation are described and we verify the sensitivity analysis and algorithm availability based on real GPS data in Korea. Consequently, this algorithm is appropriate for GNSS regional implementation.

• 한국자기공명학회논문지
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• 제26권4호
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• pp.51-58
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• 2022

The baseline flattened NMR spectrum has been achieved by several methodologies including pulse manipulation with a series of phase cycling. The background signal inherent in the probe is also main source of baseline distortion both in solution and solid NMR. The simple direct polarization with 90° pulse flipping the magnetization from the z-axis onto the receiver coil requires the strong rf pulse enough to encompass the wide frequency range to excite the resonance of interest nuclei. Albeit the perfect polarization 90° pulse, the signal from the unwanted magnetic fields such as background signal can not be completely suppressed by suitable phase cycling. Moreover, slowly baseline wiggling signal from the low 𝛾 nuclei is not easy to eliminate with multiple pulse manipulation. So there is still need to contrive the new scheme for that purpose in an adroit manner. In this article new triple pulse excitation schemes for TIP and modified DEPTH pulse sequence are analytically examined in terms of arbitrary phase and flip angle of pulse. The suitable phase cycling for these pulse trains is necessary for the good sensitivity and resolution of the spectrum. It is observed that the ¹³C sensitivity TIP experiment is almost equal to the CP/MAS with modified DEPTH sequence, both of which are applicable to both solid and solution state NMR.

• 한국자동차공학회논문집
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• 제11권3호
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• pp.161-166
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• 2003

In order to improve the fatigue lift of a lower control arm in the vehicle suspension, a new shape optimization procedure is presented. In this approach, the shape control point concept is introduced to reduce the numbers of shape design variables. Also, the two-level orthogonal way is employed to evaluate the design sensitivity of fatigue life with respect to those shape design variables, because the analytical design sensitivity information is not directly supplied from the commercial CAE softwares. In this approach, only the six design variables are used to approximate the shape of lower control arm. Then, performed are only 10 fatigue life analyses including the baseline design, 8 DOE models and the final design. The final design, the best combination obtained from the sensitivity information, can maximize the fatigue lift nearly two times as that of the baseline design, while reducing the 12 percentage of weight than it.

• 한국강구조학회 논문집
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• 제10권2호통권35호
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• pp.279-290
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• 1998

소수의 진동특성치가 실측된 삼차원 트러스 교량을 대상으로 기존의 손상추정법이 실험되었다. 첫 번째 단계로 진동모드 민감도 해석과 패턴인식기법을 사용하여 초기구조모델(baseline model)이 구성되었고, 다음 단계로 수개의 손상시나리오 수치 예를 초기구조물에 시뮬레이션하고 이를 손상지수와 패턴인식기법을 이용하여 손상위치를 예측하였다. 총 211개 요소에 11개의 부 구조계를 갖는 트러스 구조에 대하여 진동모드가 2개인 경우에 한하여 분석 검토한 결과 손상발견 알고리즘의 적합성이 입증되었다.

• 대한감각통합치료학회지
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• 제17권3호
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• pp.1-13
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• 2019

목적 : 본 연구는 능동적 구강놀이 병행한 Ayres Sensory Integration^®(ASI^®) 적용이 아동의 구강 민감도와 섭식행동의 문제에 미치는 영향에 대해 알아보고자 하였다. 연구방법 : 발달지연으로 진단받은 만 3세 6개월의 남자 아동을 대상으로 2018년 8월부터 2018년 9월까지 능동적 구강놀이 병행한 Ayres Sensory Integration^®(ASI^®)를 실시하였다. 실험설계는 단일사례연구(single-subject design) 중 ABA'설계를 사용하였고 15회기의 중재를 시행하였다. 중재기간 동안 아동의 구강민감도 변화를 측정하기 위해 임상 구강민감도 측정(Measuring Oral Sensitivity in Practice)을 실시하였다. 구강감각처리 어려움으로 섭식활동에 영향을 주는 행동은 한국형 섭취 행동 검사(Korean Children's Eating Behavior Inventory; K-CEBI), 식품 섭취 빈도 체크리스트를 중재 전후로 실시하였다. 결과 : 능동적 구강놀이와 ASI 중재기간 동안 임상 구강민감도와 섭취행동의 문제는 감소하였고 편식행동에는 변화가 없었다. 결론 : 능동적 구강놀이 병행한 ASI 중재는 아동의 구강민감도와 섭취행동의 문제를 감소하는데 긍정적인 효과가 있었다.

• Journal of Radiation Protection and Research
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• 제46권3호
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• pp.83-97
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• 2021

Background: The lifetime risk of lung cancer incidence due to radiation for nonsmokers is overestimated because of the use of the average cancer baseline risk among a mixed population, including smokers. In recent years, the generalized multiplicative (GM)-excess relative risk (ERR) model has been developed in the life span study of atomic bomb survivors to consider the joint effect of radiation and smoking. Based on this background, this paper discusses the issues of radiation risk assessment considering smoking in two parts. Materials and Methods: In Part 1, we proposed a simple method of estimating the baseline risk for nonsmokers using current smoking data. We performed sensitivity analysis on baseline risk estimation to discuss the birth cohort effects. In Part 2, we applied the GM-ERR model for Japanese smokers to calculate lifetime attributable risk (LAR). We also performed a sensitivity analysis using other ERR models (e.g., simple additive (SA)-ERR model). Results and Discussion: In Part 1, the lifetime baseline risk from mixed population including smokers to nonsmokers decreased by 54% (44%-60%) for males and 24% (18%-29%) for females. In Part 2, comparison of LAR between SA- and GM-ERR models showed that if the radiation dose was ≤200 mGy or less, the difference between these ERR models was within the standard deviation of LAR due to the uncertainty of smoking information. Conclusion: The use of mixed population for baseline risk assessment overestimates the risk for lung cancer due to low-dose radiation exposure in Japanese males.

• 환경생물
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• 제30권4호
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• pp.307-313
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• 2012

The Oriental White Stork (Ciconia boyciana) is a representative wetland species distributed across East Asia. The species has been declined to face the threat of species extinctions with estimation of at about 3000 individuals. In order to re-introduce the endangered storks in the field, we developed a baseline model using the program VORTEX, performed sensitivity test, and finally suggested an ideal model based on results of the sensitivity test. The baseline model predicted 12.5% extinction probability with mean time to first extinction of 82.0 year. Sensitivity test revealed that two demographic variables (first-year mortality and percent of adult female breeding) had the greatest impacts on population persistence. Thus, corrected model improved the population persistence, where the extinction probability decreased to 1.0% in 100 years by changing values of two variables within a range of applicable to the population. Our models for stork re-introduction suggest this population will be stable by improving first-year mortality and adult female fecundity.

• Journal of Periodontal and Implant Science
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• 제39권1호
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• pp.87-94
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• 2009

Purpose: The aim of this study was to compare the effectiveness of hydroxyapatite containing toothpaste with positive control toothpastes in reducing dentine hypersensitivity. Materials and methods: This clinical trial was a double-blind, randomized, parallel group comparison of two, namely hydroxyapatite containing toothpaste and strontium chloride containing toothpaste. A total of 55 subjects were included in this study. The subjects were given randomly assigned one of the two toothpastes after received tooth brushing instruction at baseline. Some clinical indices(PI, GI, PD), verbal rating score(VRS) for sensitivity to stimulus, the effect in relieving sensitivity and visual analogue scale(VAS) for sensitivity at baseline, week 2, week 4 and week 8 were assessed. All data were evaluated by intention-to-treat analysis. Results: Overall, PI and GI scores were significantly reduced compare baseline in all groups(p<0.05). In addition, there was significant difference in PI at 4 weeks and in GI at 4, 8 weeks between groups. The proportions of subjects relieved sensitivity were 70.4% in experimental group and 57.1% in control group at 8 weeks respectively. The VRS for sensitivity to three kinds of stimuli and VAS for sensitivity decreased according to time, there was no overall difference between two groups(p>0.05). Conclusion: This study demonstrated that the new hydroxyapatite containing toothpaste was similarly effective in reducing dentine hypersensitivity with pre-existing benchmark toothpaste.