• 한국산업융합학회 논문집
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• 제26권6_3호
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• pp.1233-1241
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• 2023

This paper investigates the efficient application of drone LiDAR technology for acquiring precise point cloud data in construction and civil engineering. A structured workflow encompassing data acquisition, processing, and accuracy verification is introduced. Practical testing on a construction site affirms that drone LiDAR surveying yields accurate and reliable data across various applications. With a focus on accuracy and verification, the results contribute to the progression of surveying methodologies in construction and civil engineering. The findings provide valuable insights into the dynamic technological landscape of these fields, establishing a foundation for more effective and precise surveying techniques. This study underscores the transformative potential of drone LiDAR technology in shaping the future of construction and civil engineering survey practices.

• Journal of Acupuncture Research
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• 제15권2호
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• pp.369-382
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• 1998

The purpose of this study was finding the pain inhibitory effect of acupuncture at $LI_4$. The pain at dentes incisivi was evoked by noxious electric stimulation and EMG changes based on the interval were measured. To do this, the opioid antagonist was administered intraperitoneally. Following are some of results. 1. The pain inhibitory effect of acupuncture at $LI_4$ was 94.35%, 84.56%, 57.62%, 54.40%, at 10, 20, 30 and 40 minutes respectively. All the data were calculated based on 100% at 0 minute. The effect was very significant at 40 minutes. 2. The continuous effect of acupuncture at $LI_4$ after taking out the needle was 58.58%, 57.62%, 66.22%, 73.18%, 83.70%, 92.68%, at 50, 50, 70, 80, 90 and 100 minutes respectively. The overall continuous effect was shown its maximum 20 minutes after taking out the needle and reached to the initial value at 60 minutes. 3. The pain inhibitory effect following the naloxone administration and acupuncture application at $LI_4$ was 95.96%, 96.04%, 94.86%, 94.92% at 10, 20, 30 and 40 minutes respectively. All values showed similar tendency to the initial data. 4. The continuous effect of acupuncture at $LI_4$ after taking out the needle which was preceded by the naloxone administration was 94.48%, 96.02%, 96.02%, 98.00%, 98.46%, 97.18% at 50, 60, 70, 80, 90 and 100 minutes respectively. This trend was not a significant fluctuation. It was concluded that effect of acupuncture at $LI_4$ was shown in conjunction with secretion of analgesic substance. Therefore it is implied that the acupuncture application will play a major role in treating many diseases with more revelation of scientific acupuncture mechanism. Further studies of acupuncture manipulation are needed in the future based on our study.

• 한국측량학회:학술대회논문집
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• 한국측량학회 2004년도 추계학술발표회 논문집
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• pp.507-512
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• 2004

LiDAR data often include outliers, the points being signficantly separated from other points and so seeming not to be measured from physical surfaces. Outliers should be removed before processing further the data for applications. Many methods have been developed for other data rather than LiDAR data as a part of data mining processes but their straightforward application to LiDAR data did not provide satisfactory results. In this study, we have thus modified one of such methods by considering the properties of LiDAR data and developed a method based on the relative point density. The proposed method have been applied to simulated and real data. The results confirms its promising performance with respect to the processing time and the detection accuracy

• 한국자기학회지
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• 제15권2호
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• pp.118-124
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• 2005

용융상태의 조성비와 동일하게 성장된 $LiNbO_3$(CLN) 단결정은 많은 내부결함으로 인하여 예리한 전자스핀 공명신호를 관측하기가 어려운데, VTE(Vapor Transport Equilibrium) 처리로 내부결함의 농도를 감소시켜주면 공명신호가 좀 더 날카롭게 관측되어 더 정밀한 스핀 하밀톤 함수의 매개상수를 결정할 수 있다. 본 연구에서는 성장된 CLN에서 알아보기 힘들었던 $Nd^{3+}$와 $Er^{3+}$의 초미세 구조를 VTE 방법으로 처리한 시료로 액체헬륨 온도에서 관측하고, 실험적으로 얻은 스펙트럼의 비등방성에서 자성이온 주위의 국소구조에 대하여 논의하였다. 분석 결과로부터 $Nd^{3+}$와 $Er^{3+}$ 희토류 이온은 $LiNbO_3$결정 내에서 Li 자리를 선호한다는 것을 제안한다.

• 한국수소및신에너지학회논문집
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• 제16권2호
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• pp.136-141
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• 2005

Li-doped NiO was synthesized by molten salt method. $LiNO_3$-LiOH flux was used as a source for Li doping. $NiCl_2$ was added to the molten Li flux and then processed to make the Li-doped NiO material. Li:Ni ratios were maintained from 5:1 to 30:1 during the synthetic procedure and the Li doping amount of synthesized materials were found between 0.086-0.190 as a Li ion to Ni ion ratio. Li doping did not change the basic cubic structural characteristics of NiO as evidenced by XRD studies, however the lattice parameter decreased from 0.41769nm in pure NiO to 0.41271nm as Li doping amount increased. Hydrogen gas sensors were fabricated using these materials as thick films on alumina substrates. The half surface of each sensor was coated with the Pt catalyst. The sensor when exposed to the hydrogen gas blended in air, heated up the catalytic surface leaving rest half surface (without catalyst) cold. The thermoelectric voltage thus built up along the hot and cold surface of the Li-doped NiO made the basis for detecting hydrogen gas. The linearity of the voltage signal vs $H_2$ concentration was checked up to 4% of $H_2$ in air (as higher concentrations above 4.65% are explosive in air) using Li doped NiO of Li ion/Ni ion=0.111 as the sensor material. The response time T90 and the recovery time RT90 were less than 25 sec. There was minimum interference of other gases and hence $H_2$ gas can easily be detected.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1998년도 추계학술대회 논문집
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• pp.25-28
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• 1998

Lithiated cobalt and nickel oxides are becoming very attractive as active cathode materials for secondary lithium ion secondary battery. $LiCoO_2$ is easily synthesized from lithium cobalt salts, but has a relatively high oxidizing potential on charge. LiNiOz is synthesized by a more complex procedure and its nonstoichiometry significantly degraded the charge-discharge characteristics. But $LiNiO_2$ has a lower charge potential which increases the system stability. Lithiated cobalt and nickel oxides are iso-structure which make the preparation of solid solutions of $LiNi_{1-x}Co_xO_2$ for O$LiCoO_2 and LiNiO_2$ electrode. The aim of the presentb paper is to study the electrochemical behaviour, as weU as the possibilities for practical application of layered Iithiated nickel oxide stabilized by $Co^{3+}$ substitution as active cathode materials in lithium ion secondary battery.

• Nuclear Engineering and Technology
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• 제55권9호
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• pp.3133-3139
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• 2023

Neutron imaging technology as a means of non-destructive detection of materials is complementary to X-ray imaging. Silicon photomultiplier (SiPM), a new type of optical readout device, has overcome some shortcomings of traditional photomultiplier tube (PMT), such as high-power consumption, large volume, high price, uneven gain response, and inability to work in strong magnetic fields. Its application in the field of neutron detection will be an irresistible general trend. In this paper, a thermal neutron imaging detector based on ⁶LiF/ZnS scintillation screen and SiPM array readout was developed. The design of the detector geometry was optimized by geant4 Monte Carlo simulation software. The optimized detector was evaluated with a step wedge sample. The results show that the detector prototype with a 48 mm × 48 mm sensitive area can achieve about 38% detection efficiency and 0.26 mm position resolution when using a 300 ㎛ thick ⁶LiF/ZnS scintillation screen and a 2 mm thick Bk7 optical guide coupled with SiPM array, and has good neutron imaging capability. It provides effective data support for developing high-performance imaging detectors applied to the China Spallation Neutron Source (CSNS).

• Nuclear Engineering and Technology
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• 제11권2호
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• pp.133-136
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• 1979

이 논문은 Ge(Li)를 이용하여 고속 중성자 에너지 스펙트럼을 재는데 사용하는 방법을 제시한다. Ge$^{72}$ 의 고속 중성자의 비탄성 충돌에 의한 691.4 KeV에서의 스펙트럼을 분석함으로써 고속중성자와 에너지 스펙트럼을 측정할 수 있는 방법을 가질 수 있음을 시사한다.

• Journal of Electrochemical Science and Technology
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• 제1권2호
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• pp.97-101
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• 2010

In order to apply hybrid capacitor, $Li_2Mn_3O_7$ was synthesized by combustion method using $LiNO_3$, $Li(CH_3COO){\cdot}2H_2O$ and $Mn(CH_3COO){\cdot}4H_2O$. Spinel pattern was identified the samples calcined over $400^{\circ}C$ in XRD. Intensity of $Mn_2O_3$ peak increased as the calcination temperature increased. To decide n/p ratio and to investigate electrochemical properties, charge-discharge tests of Li/$Li_2Mn_3O_7$ and Li/AC half-cell were carried out. Applying to AC/$Li_2Mn_3O_7$ hybrid capacitor, it had high discharge capacitance of 32.8 F/cc at 100 mA/g.

• 한국산업융합학회 논문집
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• 제26권6_3호
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• pp.1325-1332
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• 2023

Recently, much research is being conducted based on point cloud data for the growth of innovations such as construction automation in the transportation field and virtual national space. This data is often measured through remote control in terrain that is difficult for humans to access using devices such as UAVs and UGVs. Drones, one of the UAVs, are mainly used to acquire point cloud data, but photogrammetry using a vision camera, which takes a lot of time to create a point cloud map, is difficult to apply in construction sites where the terrain changes periodically and surveying is difficult. In this paper, we developed a point cloud mapping system by adopting non-repetitive scanning LiDAR and attempted to confirm improvements through field application. For accuracy analysis, a point cloud map was created through a 2 minute 40 second flight and about 30 seconds of software post-processing on a terrain measuring 144.5 × 138.8 m. As a result of comparing the actual measured distance for structures with an average of 4 m, an average error of 4.3 cm was recorded, confirming that the performance was within the error range applicable to the field.