• 한국물환경학회지
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• 제32권1호
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• pp.23-29
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• 2016

Ozonation was investigated for its ability to remove pyruvic acid in a laboratory-scale batch reactor under various experimental conditions, including UV irradiation, TiO₂ addition, and variations in temperature. An ozone flow rate of 1.0 L min^-1 and a concentration of 75±5 mg L^-1 were maintained throughout the experiment, and pH, COD, and TOC were measured at 10 min intervals during a 60 min reaction. Our results confirmed that the combination of UV irradiation and photocatalytic TiO₂ in the ozonation reaction improved the removal efficiency of both COD and TOC in aqueous solution at 20℃. Pseudo first-order rate constants and activation energies were quantified based on the COD and TOC measurements. We observed that the O₃/UV, O₃/UV/TiO₂ system increased mineralization and reduced the activation energy (E_a) necessary for pyruvic acid decomposition.

• 한국재료학회지
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• 제9권4호
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• pp.362-367
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• 1999

We intended to make the activated carbon fibers which could separate, remove and recover the volatile organic compounds of benzene, toluene, acetone and methanol. Changing activation temperature and time, large specific surface area and narrow pore distribution could be obtained. The activated carbon fibers have large adsorption capacity and selectivility for those organic compounds. We characterized the adsorption capability of the activated carbon fibers for benzene, toluene, acetone and methanol by BET specific surface area and pore size and micropore volume measurements. In the result of activation, the maximum value of BET specific surface area of the fibers was $1100\m^2$/g at $800^{\circ}C$ for 60 minutes and $K_2$O was reduced actively in this condition. Their average pore size was 5.8~5.9$\AA$. The activated carbon fibers prepared in this work had high adsorption rate to saturation and the selectibility for the above organic compounds. The adsorbed amount of acetone and methanol(diameter of$ 4.3\AA$ and $4.4\AA$ respectively) which are smaller than micropore diameter in size was 43~49%, which was larger value than benzene and toluene(in the same diameter as $5.9\AA$).

• The Journal of Korean Physical Therapy
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• 제27권1호
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• pp.1-6
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• 2015

Purpose: The purpose of this study was to examine the effects of a supplementary shouting technique on abdominal muscle activation to the rectus abdominis (RA) and external oblique (EO) muscles during performance of crunch exercise in healthy subjects. Methods: Sixty-four subjects were randomly allocated to two groups, crunch exercise with shouting group (SG) and crunch exercise with non-shouting group (NSG), with 32 subjects in each group, respectively. The interventions were conducted over three trials in each group, and measurements were performed on each subject by one examiner in three trials. Muscle activation of RA and EO was evaluated using electromyography (EMG) during performance of crunch exercise with or without shouting. Results: Our results showed a significantly greater increase in the EMG patterns of the RA and EO muscles during performance of crunch exercise in the SG compared to the NSG (p<0.01). Conclusion: These findings suggest that addition of the shouting technique during performance of crunch exercise, at the same time, would suggest positive evidence for improving activation of abdominal muscles.

• 제어로봇시스템학회논문지
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• 제16권10호
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• pp.927-932
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• 2010

Estimation methods of motion intention from bio-signal present challenges in man machine interaction(MMI) to offer user's command to machine without control of any devices. Measurements of meaningful bio-signals that contain the motion intention and motion estimation methods from bio-signal are important issues for accurate and safe interaction. This paper proposes a novel motion estimation sensor based on a geometrical muscle changes, and a motion estimation method using the sensor. For estimation of the motion, we measure the circumference change of the muscle which is proportional to muscle activation level using a flexible piezoelectric cable (pMAS, piezo muscle activation sensor), designed in band type. The pMAS measures variations of the cable band that originate from circumference changes of muscle bundles. Moreover, we estimate the elbow motion by applying the sensor to upper limb with least square method. The proposed sensor and prediction method are simple to use so that they can be used to motion prediction device and methods in rehabilitation and sports fields.

• Nuclear Engineering and Technology
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• 제53권5호
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• pp.1491-1510
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• 2021

This work presents an illustration of Nagra's AMAC (Advanced Methodology for Activation Characterization) approach to the South Korean pressurized water reactor Kori-1 decommissioning. The results achieved are supported by the existing experience from the detailed AMAC applications to Swiss NPPs and are used not only for a demonstration of the applicability of AMAC to South Korean NPPs, but also for a first approximation of the activated waste volumes to be expected from Kori-1. A packaging concept based on the above activation characterization is also presented, using the AMAC algorithmic optimization software ALGOPACK leading to the minimum number of waste containers needed given the selected packaging constraints. Nagra's AMAC enables effective planning before and during NPP decommissioning, including recommendations for cutting profiles for diverse reactor components and building structures. Finally, it is expected to lead to significant cost savings by reducing the number of expensive waste containers, by optimizing a potential melting strategy for metallic waste as well as by significantly limiting the number of radiological measurements. All information about Kori-1 used for the purpose of this study was collected from publicly available sources.

• Nuclear Engineering and Technology
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• 제56권1호
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• pp.328-334
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• 2024

The activation method of metallic foils is an important technique to measure the flux and energy of proton beams. In this paper, the method was used to measure the CSNS APEP proton flux at seven nominal proton energies ranging from 10 MeV to 70 MeV for beam spot sizes of the 20 mm × 20 mm and 50 mm × 50 mm. The reactions of ^natTi(p, x)⁴⁸V, ^natNi(p, x)⁵⁷Ni, ^natCu(p, x)⁵⁸Co, and ²⁷Al(p, x)²⁴Na were employed to measure the proton beam flux with a range of 10⁷-10⁹ p/cm²/s. Furthermore, we also proposed a method using the activity ratio with a stacked-foil target to determine the energy spread of a Gaussian-like distribution for different nominal proton energies. The optimal combinations of Al, Cu, Ti, Ni, Mo, Fe, Nb, and In foils were adopted for the proton energies. The measured energy spreads for degraded beams of 30 MeV-70 MeV were found to be smaller than 10.00%.

• 대한치과교정학회지
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• 제46권2호
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• pp.65-72
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• 2016

Objective: The purposes of this study were to measure the orthodontic forces generated by thermoplastic aligners and investigate the possible influences of different activations for lingual bodily movements on orthodontic forces, and their attenuation. Methods: Thermoplastic material of 1.0-mm in thickness was used to manufacture aligners for 0.2, 0.3, 0.4, 0.5, and 0.6 mm activations for lingual bodily movements of the maxillary central incisor. The orthodontic force in the lingual direction delivered by the thermoplastic aligners was measured using a micro-stress sensor system for the invisible orthodontic technique, and was monitored for 2 weeks. Results: Orthodontic force increased with the amount of activation of the aligner in the initial measurements. The attenuation speed in the 0.6 mm group was faster than that of the other groups (p < 0.05). All aligners demonstrated rapid relaxation in the first 8 hours, which then decreased slowly and plateaued on day 4 or 5. Conclusions: The amount of activation had a substantial influence on the orthodontic force imparted by the aligners. The results suggest that the activation of lingual bodily movement of the maxillary central incisor should not exceed 0.5 mm. The initial 4 or 5 days is important with respect to orthodontic treatment incorporating an aligner.

• 대한물리의학회지
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• 제11권2호
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• pp.53-62
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• 2016

PURPOSE: The purpose of this study was to investigate the effects of a supplementary Ki-hap technique and verbal encouragement on the activation of abdominal muscles during performance of crunch exercise in healthy subjects. METHODS: 93 subjects were randomly allocated to three group, crunch exercise group (CG), crunch exercise with Ki-hap group (CKG), and crunch exercise with Ki-hap and verbal encouragement group (CKVG), with 31 subjects in each group, respectively. The interventions were conducted over three trials in each group, and measurements were performed on each subject by one examiner in three trials. The activation of rectus abdominis (RA), external oblique (EO), and internal oblique (IO) muscles were evaluated using electromyography (EMG) during performance of crunch exercise with non-Ki-hap, Ki-hap and Ki-hap combined with verbal encouragement. RESULTS: Our results showed a significantly greater increase in the EMG patterns of all muscles during performance of crunch exercise in the CKG (p<0.05) compared to the CG and CKVG. The results also showed that there were significantly greater increase in the activation of EO and IO muscles in those of the CKVG (p<0.05) compared with the CG. CONCLUSION: These findings demonstrated that addition of the Ki-hap technique and verbal encouragement during performance of crunch exercise, at the same time, would suggest positive evidence for improving activation of abdominal muscles.

• 폴리머
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• 제36권3호
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• pp.321-325
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• 2012

본 연구에서는 화학적으로 활성 흑연나노섬유를 제조하여 그에 따른 전기화학적 거동을 확인하였다. 활성화제로 KOH를 사용하였으며, KOH와 흑연나노섬유의 비를 무게비로 각각 0, 1, 2, 4, 및 5로 처리하여 표면과 기공특성을 연구하였고, 그에 따른 전기화학적 거동을 살펴보았다. 활성화된 흑연나노섬유의 결정구조와 표면특성은 각각 X-선 회절분석법(XRD), 주사전자현미경(SEM) 분석방법을 이용하여 확인하였으며, 기공 특성은 비표면적 장치(BET)를 이용하였으며 질소흡착 등온선에 의해 조사하였다. 전기화학적 특성은 10 mV/s의 주사속도로 순환전류전압(cyclic voltammetry)을 통한 곡선으로 고찰하였으며 정전류법(galvanostatic method)으로 측정된 충방전 곡선을 통해 비축전용량을 계산하였다. 실험 결과로부터, 활성 흑연나노섬유의 전기화학적 거동은 KOH 양이 증가함에 따라 향상되었으며, 4 배 처리된 활성 흑연나노섬유가 최대의 비축전용량을 가진 것으로 나타났다. 이것은 KOH 활성화에 의해 활성 흑연나노섬유의 비표면적과 기공부피가 증가하기 때문인 것으로 사료된다.

• 마이크로전자및패키징학회지
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• 제21권4호
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• pp.41-44
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• 2014

본 연구에서는 $TiO_2$에 나이오븀 (Nb) 도펀트가 주입되었을 때의 활성화 에너지를 홀 효과 측정 시스템과 온도에 따른 photoluminescence (PL) 실험을 통하여 살펴보았다. Nb 이 도핑 된 n형 아나타제 $TiO_2$ 박막은 pulsed laser deposition (PLD) 기법으로 $SrTiO_3$기판에 성장되었다. 측정 결과, Nb 도너의 활성화 에너지 값은 홀 효과 측정에서는 14.52 meV, PL 측정에서는 6.72 meV로 다소 차이를 보였다. 이 결과는 기존의 어셉터 물질의 활성화 에너지들과는 차이를 나타내고 있으며, 향후 본 연구와 같은 shallow 도너 준위의 활성화 에너지 연구에 대한 더 많은 연구가 필요할 것으로 판단된다.