• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.47 no.6
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• pp.438-445
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• 2019

In this paper, we present a new approach to extract the g-sensitivity scale-factor error for a MEMS gyroscope. MEMS gyroscopes, based on the use of both angular momentum and the Coriolis effect, have a g-sensitivity error due to mass unbalance. Generally, the g-sensitivity error is not considered in general use of gyroscopes, but it deserves our attention if we are to develop for tactical class performance and reliability. The g-sensitivity error during vehicle flight increases navigation error; so it must be analyzed and compensated for the use of MEMS IMU for high dynamics vehicle systems. Therefore, we analyzed how to extract the g-sensitivity scale-factor error from the inertial sensor error model. Furthermore we propose a new method to extract the g-sensitivity error using flight motion simulator. We verified our proposed method with experimental results.

• Journal of the Korea Society of Computer and Information
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• v.27 no.10
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• pp.105-113
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• 2022

In this paper, we present and analyze 5G system and IEEE time-sensitive networking(TSN) and propose a novel mobility management scheme for time sensitive communications in 5G-TSN to support ultra-low latency networks. Time-sensitive networking(TSN) has a promising future in the Industrial Automation and Industrial Internet of Things(IIoT), as a key technology that is able to provide low-latency, high-reliable and deterministic communications over the Ethernet. When a TSN capable UE moves the TSN service coverage from the non-TSN service coverage, the UE cannot get the TSN service promptly because the related mobility management is not performed appropriately. For the mobility situation with the TSN service coverage, the proposed scheme reports TSN capability to the network and triggers the initial registration in order to be provided the TSN service immediately and ultra-low latency communications compared to existing schemes in 5G mobile networks.

• Neonatal Medicine
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• v.17 no.2
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• pp.217-223
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• 2010

Purpose: To evaluate the validity of the Korean Ages and Stages Questionnaire (K-ASQ) in premature infants. Methods: Infants with a gestational age of less than 37 weeks were assessed with K-ASQ and Bayley Scales of Infant Development-III (BSID-III) at the outpatient clinic of Seoul National University Children's Hospital between October 30, 2006 and August 1, 2010. Less than 1 standard deviation of the ASQ was defined as positive, and the results were compared with those of BSID-III. Results: The mean gestational age of subjects in the study group was 28$\pm$2.87 weeks (median, 28.43 weeks; range, 23.57-35.86weeks), and the mean birth weight was 1,027$\pm$363 g (median, 950 g; range, 480-2,870 g). The sensitivity of K-ASQ at 8 month was 0.2, and the specificity was 0.93. The sensitivity of K-ASQ at 18 months was 0.72, and the specificity was 0.94. The validity of each of the 4 matched subunits was separately compared, and it also had a high specificity and a low sensitivity. In addition, KASQ showed a higher sensitivity at 18 months than at 8 months. Conclusion: ASQ was developed to screen the general population, and its specificity has been powered. The specificity was also proven in our study. The results of this study suggest that although screening use of K-ASQ in preterm infants may have some limitations, the specificities at 8 and 18 months can be clinically implicated. Further studies are needed to confirm our results.

• Journal of the Korean Society for Marine Environment & Energy
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• v.5 no.4
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• pp.48-56
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• 2002

It was peformed to estimate the sensitivity analyses and mass balance for tributyltin in Masan Bay, using the model builded by stella program. The results of the sensitivity analysis for dissolved tributyltin and tributyltin in the particulate organic carbon showed that not only organic carbon partition coefficient but also settling rate is important. In the case of tributyltin in phytoplankton, bioconcentration factor of phytoplankton is most important. The results of the mass balance showed that standing stocks of tributyltin in water, in phytoplankton and in particulate organic carbon are 3.29×10⁴g, 1.16×10²g and 3.17×10³g, respectively. In the case of flux, partition to particulate organic carbon showed most high value, 1.64×10³g/4ay, and next were deposition to sediment, 1.64×10³g/day and transportation to open sea by tide, 1.64×10³g/day.

• Applied Chemistry for Engineering
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• v.26 no.1
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• pp.47-52
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• 2015

To improve both the GOD immobilization capability and sensitivity of MWCNTs-based biosensor electrode, the electrode was prepared by adding different quantities of GO. The addition of GO increased hydrophilicity and the surface free energy of electrodes for glucose sensing as well as the dispersion of MWCNTs. In addition, the GOD immobilization capability was enhanced and the sensitivity was improved up to $121{\mu}A\;mM^{-1}$ even though having a high $K_m$ value (0.105) when adding 0.05 g GO to 0.05 g MWCNTs. These experimental results were attributed to the fact that the improvement in dispersion stability for MWCNTs, hydrophilicity, and surface free energy of electrode surface due to the addition of GO affected GOD immobilization capability.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.63 no.8
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• pp.1075-1079
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• 2014

In this paper, we describe the analysis and the compensation method of the g-sensitivity error for MEMS vibratory gyroscopes. Usually, the g-sensitivity error has been ignored in the commercial MEMS gyroscope, but it deserves our attention to apply for the missile application as a tactical grade performance. Thus, it is necessary to compensate for the g-sensitivity error to reach a tactical grade performance. Generally, the g-sensitivity error seems intuitively to be a gyroscope bias error proportional to the linear acceleration. However, we assert that the g-sensitivity error mainly causes not a bias error but a scale-factor error. And we verify that the g-sensitivity scale-factor error occurs due to the non-linearity of parallel plate electrodes. Therefore, we propose the compensation method to remove the g-sensitivity scale-factor error. The experimental result showed that a proposed compensation method improved successfully the performance of the MEMS vibratory gyroscope.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2004.06a
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• pp.52-57
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• 2004

In order to analyze key parameters of important radionuclides in dose evaluation model of decommissioning site, a sensitivity analysis was performed. This analysis assumed a resident farmer for an exposure scenario and 0.037Bq/g for the concentration of radionuclides. As a result of sensitivity analysis, the key parameters of radionuclides considered were the area of contaminated zone, external gamma shielding factor and indoor time fraction for Cs-137 and Co-60. The key parameters for C-14 were the environmental parameters and hydrological parameters of unsaturated zone. Also, the key parameter for Sr-90 was the density of contaminated zone.

• Parasites, Hosts and Diseases
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• v.24 no.1
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• pp.25-41
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• 1986

The applicability of micro-ELISA was evaluated in human neuro-cysticercosis using paired samples of serum and CSF. A total of 355 cases who were mostly neurologic patients was subjected. Cystic fluid of C. cellulosae was used as antigen in protein concentration of $2.5{\;}{\mu}g/ml$. Serum was diluted to 1 : 100 and CSF was undiluted in the assay for the specific IgG antibody level. The differential criterion of the positive reaction was the abs. of o. 18 in both samples. The results were summarized as follows: 1. The overall sensitivity of the micro-ELISA in 71 confirmed neurocysticercosis was 90.1% ; the sensitivity by serum was 77.5% and that by CSF was 83.1%. CSF was a more sensitive and valuable material. Most of the false negative cases of neuro-cysticercosis showed far lower level of abs. rather than marginal. 2. The overall specificity of the micro-ELISA in 52 confirmed other neurologic diseases was 88.5%; the specificities by serum and by CSF were 94.2% respectively. Cases of other neurologic diseases did not show false positive reactions in both samples. 3. When serum was assayed, taeniasis(2/18), sparganosis(2/20), paragonimiasis(1/56), clonorchiasis(1/15) and fascioliasis(1/1) cases showed cross reactions. When CSF was assayed, 2 ot 10 neuro-sparganosis showed cross reactions while none of 9 neuro-paragonimiasis showed it. Out of 71 confirmed neuro-cysticercosis cases, 6 and 11 showed cross reactions by serum and CSF to crude extract antigen of sparganum; but no case did show it to crude extract antigen of Paragonimus westermani. 4. Ventricular CSF showed low or negative levels of IgG antibody than lumbar CSF unless the lesion was at the lateral ventricle itself. 5. Out of 4 racemose cysticercosis cases, 3 showed positive reaction in serum while all of 3 examined CSF were positive. The above results indicated that the serological test for detecting the specific IgG antibody by micro-ELISA using paired samples of serum and CSF was very helpful for clinical differentiation of neuro-cysticercosis from neurologic diseases of other causes.

• Journal of the Korean Geotechnical Society
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• v.17 no.1
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• pp.57-65
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• 2001

역사적 지진 발생 기록이 풍부하고 양산 단층 영향권 내에 있어 지진 발생 가능성이 높은 경주 지역을 대상으로 지진민감도 분석을 수행하였다. 지형적 특성을 고려한 지반조사와 현장 및 실내 시험을 통하여 대상 지역 지반의 지층 구성과 각 지층의 동적 특성을 분석 평가하고, 이를 토대로 한 지반 응답 해석을 수행하였다. 9개의 시험공을 시추하여 2개소의 크로스홀 시험과 7개소의 다운홀 시험을 실시하였고, 시추부지 포함 13개소에서 SASW 시험도 수행하였다. X선 회절 및 풍화도 분석과 공진주 시험 등의 실내시험도 병행하였다. 이러한 시험 결과를 바탕으로 El Centro 지진에 의한 지표면 최대 가속도를 등가 선형 부지응답해석을 통해 평가한 결과 붕괴방지 수준에서 0.158g~0.286g, 기능수행 수준에서 0.067g~0.116g의 분포를 보였고 퇴적층에 의하여 형성된 경주 시가지 분지 지형에서 증폭정도가 심하다는 것을 알 수 있었다. 해석 결과로 볼 때, 현행 건교부 기준 설계응답스펙트럼은 경우에 따라 지반 운동을 과소평가하고 지반 고유의 공진 현상을 고려하지 못하였다. 이러한 문제를 해결하기 위하여 개선된 지반 분류방법을 소개하였고 부지고유의 지반응답평가의 중요성에 대해 제시하였다.

• Journal of the Korean Magnetics Society
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• v.10 no.6
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• pp.310-317
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• 2000

With use of (G)MR head, thermal asperity (TA) has been a big concern in drive industry. In this study, we investigated several factors of heads and disks which affects the TA sensitivity of the drive. TA experiments were conducted by introducing the particles on the drives using a particle injection chamber. It was found that the slider ABS shape can help to reduce TA or contamination in the head/media interface. However, TA sensitivity of the drive mainly depend on the intrinsic property of (G)MR sensor. GMR head is much less sensitive to TA compared with MR head. However, in case that the same bias current was applied for both of MR and GMR head, TA sensitivity of GMR head became almost identical to that of MR head. Therefore it was found that the bias current is a dominant factor in determining TA sensitivity of the head. TA sensitivity of different types of disks was also studied. The scratch resistance of the carbon overcoat layer is the one of the main factors which influence TA rejection capability of the disks.