• Title/Summary/Keyword: Indirect Measurement

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Mobility-Spectrum Analysis of an Anisotropic Material System with a Single-Valley Indirect-Band-Gap Semiconductor Quantum-Well

  • Joung, Hodoug;Ahn, Il-Ho;Yang, Woochul;Kim, Deuk Young
    • Electronic Materials Letters
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    • v.14 no.6
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    • pp.774-783
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    • 2018
  • Full maximum-entropy mobility-spectrum analysis (FMEMSA) is the best algorithm among mobility spectrum analyses by which we can obtain a set of partial-conductivities associated with mobility values (mobility spectrum) by analyzing magnetic-field-dependent conductivity-tensors. However, it is restricted to a direct band-gap semiconductor and should be modified for materials with other band structures. We developed the modified version of FMEMSA which is appropriate for a material with a single anisotropic valley, or an indirect-band-gap semiconductor quantum-well with a single non-degenerate conduction-band valley e.g., (110)-oriented AlAs quantum wells with a single anisotropic valley. To demonstrate the reliability of the modified version, we applied it to several sets of synthetic measurement datasets. The results demonstrated that, unlike existing FMEMSA, the modified version could produce accurate mobility spectra of materials with a single anisotropic valley.

Measurement of Spray Distribution of Swirl Injector by Tomography method (토모그래피 기법을 이용한 스월 인젝터의 분무 분포 계측)

  • Park, Gu-Jeong;Cho, Seong-Ho;Chung, Jae-Mook;Kim, Tae-Sung;Yoon, Young-Bin
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2011.04a
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    • pp.39-44
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    • 2011
  • This study constructed the spray distribution by the Tomography method at high pressure condition. The constructed spray distribution was compared with the images by Indirect Photography method so that the spray size was confirmed and took the boundary of the distribution. It was confirmed that the Tomography applies to construct the distribution at high pressure.

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The Measurement Method of Lateral Displacement in Bridge Abutment. (교량구조물의 측방이동 측정방법에 관한 연구)

  • 장용채
    • Journal of Korean Port Research
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    • v.14 no.1
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    • pp.115-124
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    • 2000
  • This study is a suggest a measurement method of lateral displacement, which can be used to judge the stability of bridge abutment on soil undergoing lateral movement. The abutment of bridge on soft foundation makes lateral movement due to the settlement of back fill and lateral flow. To measure the displacement of such a abutment, there are a lot of indirect method for measurement such as survey of leveling or inclinometer gauge around the abutment. But all of them are not sufficient to confirm the ground behavior and measure the exact lateral behavior of structure. As making the structure and pile cooperatively by measuring the movement of lateral displacement, for measuring the abutment displacement precisely by using the inclinometer. In this work, we try to suggest efficient measuring method of abutment displacement and its application.

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A Study on the Insulation Resistance Measurement Technique for Electrical Safety of Green Car (친환경자동차의 전기안전을 위한 절연저항 측정에 관한 연구)

  • Lee, Ki-Yeon;Kim, Dong-Ook;Kim, Hyang-Kon;Moon, Hyun-Wook
    • The Transactions of the Korean Institute of Electrical Engineers P
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    • v.58 no.4
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    • pp.597-601
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    • 2009
  • Green car such as a hybrid electrical vehicle and fuel cell vehicle is developed as a commercial target. UN/ECE/WP29 is developing GTR of HFCV and establishing the regulation and standard of electrical safety by ELSA. The regulation and standard about Electrical safety of vehicle are prescribed in ISO, UN/ECE, FMVSS, Japanese Attachment and so on, in case of insulation resistance is referred to keep more than 100/Vdc, 500/Vac. However, accurate method to measure insulation resistance agreeable to structure of vehicle does not exist now, it is actually that correctness of measurement drops according to the feature of battery and fuel cell stack. In this paper, the method to measure insulation resistance for protection against electrical shock by direct contact or indirect contact in Green Car will be indicated by making a comparison between the insulation measurement in standard of electrical safety and the experiment results for HEV and HFCV.

A Study on Lower Bodyshape from Classification of Obese Women (비만 여성의 하반신 체형 유형화에 관한 연구)

  • 이진희
    • Journal of the Korean Society of Clothing and Textiles
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    • v.24 no.2
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    • pp.237-244
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    • 2000
  • This study was carried out on 91 obese women who satisfied both of the conditions for obesity: over 1.6 in Rohrer index and over 90cm in bust girth. The purpose of this study was to analyze and classify the lower body of obese women and find out their respective characteristics. Twenty seven measurement items(21 direct measurement items and 6 indirect measurement items) were used for factor-analysis and cluster-analysis. In the study of lower body type, 7 factors were as a result of factor analysis and those factors were comprise 75.9% of total variance. Lower bodyshape were classified 3 types according to the cluster analysis. Type 1 was protrude of the hip, type 2 was short leg and protrude of the abdominal region and type 3 was obese of hip and long leg.

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Aided Navigation Algorithm for Land Navigation System Using VMS with Indirect Drive Condition (직진성이 보장되지 않는 조건에서 지상항법시스템의 속도계를 이용한 보정항법 알고리즘)

  • Kim, Hyungsoo
    • Journal of Advanced Navigation Technology
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    • v.20 no.4
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    • pp.314-320
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    • 2016
  • Inertial navigation system (INS) has used aided systems and sensors to compensate navigation error. Global navigation satellite system (GNSS), velocity measurement sensor (VMS), and radar are commonly used to aid INS. Land navigation system (LNS) also mainly uses VMS when GNSS cannot be used such as at tunnel or on jammed scenario. A straight drive is required when VMS-aided navigation is used, because there is only speed of straight direction whereas no crossways and vertical directions. In local environment, even an expressway has lack of straight drive which is constraint of VMS-aided navigation algorithm. This paper proposes an enhanced VMS-aided navigation algorithm for LNS with indirect drive by restricting filter update condition. Also, there is a result of vehicle test to prove performance of the proposed algorithm.

Analyzing Effects on Firms' Market Value of Personal Information Security Breaches (개인정보 유출이 기업의 주가에 미치는 영향)

  • Kim, JeongYeon
    • The Journal of Society for e-Business Studies
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    • v.18 no.1
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    • pp.1-12
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    • 2013
  • With the increases of requirement for user identification in Internet services, we should let the service companies know my personal information. If the shared personal information with them are used in not-allowed area or delivered to un-authorized persons, we may have practical harms in several fields such as financial related operations. Korean Government has introduced new management method for personal information, but it is not hard to find the personal information management issues from Korean news papers. The proper measurement should be delivered to related companies to help them to decide investment for security. This paper review the indirect measurement method of demages by check the stock prices of related company for personal information management issue. We check the relationship between change of stock price and the information management issue. The result shows there are no changes in stock market. Korean government added strong regulations for personal information management though. To prevent further personal information issues, we should recognize the indirect damages properly and let the company pay higher reparations for any personal information abuse.

Comparison of shearbond strength between metal and indirect resin according to the different conditionings (표면처리에 따른 금속과 간접복합레진간의 전단결합강도 비교연구)

  • Choi, Su-Young;Choi, Hyunmin;Moon, Hong-Seok;Shim, June-Sung;Park, Young-Bum;Lee, Geun-Woo
    • The Journal of Korean Academy of Prosthodontics
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    • v.55 no.3
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    • pp.264-271
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    • 2017
  • Purpose: The purpose of this study is to investigate the differences in bond strength of four different indirect composites to the gold alloy and Ni-Cr alloy according to type of metal surface treatment after water storage. Materials and methods: Type IV gold alloy and Ni-Cr alloy were used for casting alloy while four types of indirect composite resins (Gradia, Tescera Sinfony and in;joy) were used in this study. Metal specimens were produced by casting and total of 240 specimens (60 specimens per one indirect composite group) were prepared. After bonding indirect composite resin and undergoing 24 hours of polymerization, customized jig was attached to the metal specimen and shear bond strength were measured using universal testing machine. Also, differences in shear bond strength before and after water storage for 240 hours were also measured. Results: In the measurement of shear bond strength according to the metal surface treatments, bead group showed high strength followed by loop and flatting group (P<.05). After being stored in water bath for 240 hours, Gradia showed statistically significant high bond strength compared to other indirect composite resins in all groups (P<.05). Conclusion: Shearbond strength was found to be different according to type of metal surface treatment and type of metal used after storage in water. Further studies need to be developed for clinical practices as three are still problems of microleakage, stain or wear.

ECG Measurement Method during Sleep with Array of Capacitive Electrodes Attached to Bed (침대에 부착된 용량성 전극 배열을 이용한 수면 중의 심전도 측정)

  • Lim, Y.G.;Kim, K.K.;Park, K.S.;Jeong, D.U.
    • Proceedings of the IEEK Conference
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    • 2005.11a
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    • pp.521-524
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    • 2005
  • In order to measure ECG in daily life, a new ECG measurement method on bed was developed. The provided method does not require any direct conductive contact between the instrument and bare skin, so that it does not cause the uncomfortable feel of touch and the possible skin trouble which are typical shortcomings of the conventional conductive contact ECG measurement. The provided method utilized an array of high-input-impedance active electrodes fixed on the mattress and an indirect-skin-contact ground made of a large conductive textile sheet and laid on lower area of the mattress. A thin cotton bedcover covered the mattress, the electrodes, and the conductive textile and subjects lay on the mattress over the bedcover. ECG was obtained successfully. However its signal quality is lower and the motion artifact is larger than direct-contact measurement. Careful measurement setup was needed to reduce the motion artifact originated from variation in static electricity. From the ECG obtained by the provided method, R-peak could be discriminated easily and the information about the position and the posture of the subject could be obtained.

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An Approach to Measure Anthropometric Data of Simulated Human Hand Using Photogrammetry (시뮬레이션 환경에서 사진측량기법을 이용한 손 치수 측정 방법에 대한 연구)

  • Chang, Ji Hong
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.9 no.5
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    • pp.511-517
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    • 2016
  • Anthropometric data of the hand is one of the important issues for the product design related with hand and manual operation in terms of user-centered design. Direct measurement, which traditionally uses anthropometric measuring tool, has a few disadvantages in cumulation of measuring time, possible errors in raw data, doubtful reliability between inspectors. Newly introduced 3D scanning technology overcomes those disadvantages; however, another disadvantages, such as, hight cost and immovability, have been introduced. In this study, photogrammetric approach was introduced for the measurement of anthropometric data in hand. In order to minimize the possibility of error during direct and indirect measurement, a simulated object was used and effectiveness of photogrametric measurement was confirmed for the collection of anthropometric data in hand.