• 한국대기환경학회지
• /
• 제22권6호
• /
• pp.922-928
• /
• 2006

An absolute absorption cross section of benzene was measured with a spectrometer system including a mono-chrometer and a grating in the wavelength region of $240{\sim}280nm$ under the atmospheric pressure and room temperature in the laboratory. A certificated reference benzene gas ($98{\mu}mol/mol$ in $N_2$) was used to measure its absorption cross section. A 710 mm cell with a quartz window and a 150 W Xe arc lamp were employed. The magnitude of absorption cross section of $1.41{\times}10^{-18}cm^2$ was lower than that of the reference spectra ($2.5{\times}10^{-18}cm^2$) of high resolution spectrometer, Total measurement uncertainty was estimated to be 4.0%.

• 소음진동
• /
• 제8권5호
• /
• pp.870-878
• /
• 1998

The cross-flow fan which constitutes a fan-duct system with a stabilizer and a scroll casing is widely used in many air-ventilating and air-conditioning devices. Its ooperating points of high efficiency and loading conditions frequently induce a annoying sharp tonal component of discrete frequency on the noise spectrum, which is open called as a BPF(Blade-Passing-Frequency) noise and degrades the sound quality of the devices. this BPF tone has been one of the defects of the cross-flow fan. This study proposes two methods in order to reduce this tonal noise component, which are the random distributions of the fan blades and the skewed shapes of the stabilizer. The proposed methods are verified by a simple analytical model and are applied in manufacturing the cross-flow fan and the stabilizer samples. Some experiments are carried out to verify the reduction capability of BPF tones of above two schemes and the experimental results are analyzed. The comparison between two method is also carried out.

• Journal of Radiation Protection and Research
• /
• 제1권1호
• /
• pp.1-9
• /
• 1976

핵임계사고시(核臨界事故時)에 방출(放出)되는 속중성자(速中性子)가 산란중성자(散亂中性子)로 중첩(重疊)되어 있는 상태(狀態)에서 방사화(放射化) 및 발단방사화검출기(發端放射化檢出器)를 이용(利用)하여 속중성자(速中性子)를 측정(測定) 및 해석(解析)할 수 있는 한 방법(方法)을 제안(提案)하였으며 이 측정(測定)에 있어서 주요인자(主要因子), 즉(卽) 몇개의 발단방사화검출기(發端放射化檢出器)에 대(對)한 평균핵반응단면적(平均核反應斷面積)과 중성자당선량환산계수(中性子當線量換算係數)를 전자계산기(電子計算機)로 계산(計算)하였다. 그 결과(結果) 핵분열중성자(核分裂中性子)의 스펙트럼 측정(測定)에는 발단(發端)에너지가 높은 검출기(檢出器)가 유리(有利)한 것에 반(反)해 발단(發端)에너지가 낮은 것은 산란매질(散亂媒質)이 없는 핵임계장치(核臨界裝置)의 사고시(事故時)에 있어서 속중성자(速中性子)의 시적분선속밀도(時積分線束密度) 측정계(測定計) 유용(有用)한것 같았다. 그리고 유황(硫黃)의 (n, p) 핵분열(核分裂)에 대(對)한 평균단면적(平均斷面積)은 핵분열(核分裂) 중성자(中性子)의 해석적(解析的) 표현식(表現式)에 무관(無關)한 것 처럼 보였다 .그밖에 중성자당(中性子當) 선량환산계수(線量換算係數)의 변화(變化)는 핵분열(核分裂) 중성자(中性子) 스펙트럼의 해석적(解析的) 표현식(表現式)과 핵분열상태(核分裂形態)에 따라 민감(敏感)하게 변화(變化)되지 않은 것 같았다.

• 한국음향학회지
• /
• 제40권1호
• /
• pp.1-9
• /
• 2021

해수면 상태에 따른 고주파 양상태 해수면 음파산란 채널 측정 실험은 2020년 4월 거제 내만해역에서 수행되었으며 산란이론을 기반으로 한 모의결과와 비교하였다. 신호는 중심주파수 128 kHz, 대역폭 32 kHz의 선형 주파수 변조 신호를 이용하였다. 파고부이를 통해 측정된 해수면 거칠기로부터 해수면 파수 스펙트럼을 계산하였고 산란이론인 Small Slope Approximation(SSA)에 적용하여 해수면 거칠기에 의한 산란강도를 추정하였다. 또한 실험 당시 풍속을 이용하여 해수면 부근 공기방울층 음파산란을 고려하여 산란강도를 계산하였다. 모의된 산란강도를 이용하여 해수면 산란 채널 세기 임펄스 응답을 모의하였고, 해수면 파수 스펙트럼과 공기방울층 산란에 따른 모의결과를 측정치와 비교, 분석하였다.

• 한국근적외분광분석학회:학술대회논문집
• /
• 한국근적외분광분석학회 2001년도 NIR-2001
• /
• pp.4102-4102
• /
• 2001

In multivariate analysis, absorbance spectrum is measured over a band of wavelengths. One does not often pay attention to the size of this wavelength band. However, it is desirable that spectrum is measured at only necessary wavelengths as long as the acceptable accuracy of prediction can be met. In this paper, the method of selecting an optimal band of wavelengths based on the loading vector analysis was proposed and applied for determining total protein in human serum using near-infrared transmission spectroscopy and PLSR. Loading vectors in the full spectrum PLSR were used as reference in selecting wavelengths, but only the first loading vector was used since it explains the spectrum best. Absorbance spectra of sera from 97 outpatients were measured at 1530∼1850 nm with an interval of 2 nm. Total protein concentrations of sera were ranged from 5.1 to 7.7 g/㎗. Spectra were measured by Cary 5E spectrophotometer (Varian, Australia). Serum in the 5 mm-pathlength cuvette was put in the sample beam and air in the reference beam. Full spectrum PLSR was applied to determine total protein from sera. Next, the wavelength region of 1672∼1754 nm was selected based on the first loading vector analysis. Standard Error of Cross Validation (SECV) of full spectrum (1530∼l850 nm) PLSR and selected wavelength PLSR (1672∼1754 nm) was respectively 0.28 and 0.27 g/㎗. The prediction accuracy between the two bands was equal. Wavelength selection based on loading vector in PLSR seemed to be simple and robust in comparison to other methods based on correlation plot, regression vector and genetic algorithm. As a reference of wavelength selection for PLSR, the loading vector has the advantage over the correlation plot since the former is based on multivariate model whereas the latter, on univariate model. Wavelength selection by the first loading vector analysis requires shorter computation time than that by genetic algorithm and needs not smoothing.

• BMB Reports
• /
• 제45권7호
• /
• pp.408-413
• /
• 2012

Almost all melanoma cells express at least one member of the MAGE-A antigen family, making the cytotoxic T cells (CTLs) epitopes with cross-immunizing potential in this family attractive candidates for the broad spectrum of anti-melanoma immunotherapy. In this study, four highly homologous peptides (P264: FLWGPRALA, P264I9: FLWGPRALI, P264V9: FLWGPRALV, and P264H8: FLWGPRAHA) from the MAGE-A antigens were selected by homologous alignment. All four peptides showed high binding affinity and stability to HLA-A$^*02:01$ molecules, and could prime CTL immune responses in human PBMCs and in HLA-A$^*02:01/K^b$ transgenic mice. CTLs elicited by the four epitope peptides could cross-lyse tumor cells expressing the mutual target antigens, except MAGE-A11 which was not tested. However, CTLs induced by P264V9 and P264I9 showed the strongest target cell lysis capabilities, suggesting both peptides may represent the common CTL epitopes shared by the eight MAGE-A antigens, which could induce more potent and broad-spectrum antitumor responses in immunotherapy.

• Clinics in Shoulder and Elbow
• /
• 제21권2호
• /
• pp.67-74
• /
• 2018

Background: Fatty degeneration of rotator cuff is a well-known predictor of postoperative outcome. The purpose of this study was to evaluate the clinical features of rotator cuff tears involving subscapularis, and investigate whether fatty degeneration quantified from only the upper subscapularis correlates better with clinical outcomes than quantified from the whole subscapularis. Methods: We retrospectively analyzed 315 consecutive patients who underwent arthroscopic repair for rotator cuff tears involving subscapularis with a minimum follow-up of 1 year. Preoperative and postoperative visual analogue score for pain, range of motion and functional scores were assessed. Integrity of the repaired tendon was assessed at the 1-year follow-up with either magnetic resonance imaging or ultrasonography. Results: The mean Goutallier grade of whole cross-section was significantly lower than that of upper cross-section (1.59 vs. 1.71, p<0.05), but significantly higher than that of lower cross-section (1.59 vs. 1.01, p<0.05). In analysis of 37 re-tears, the occupancy of severe fatty degeneration in upper cross-section was 86.5%, which was significantly higher than that seen in whole cross-section (56.8%, p<0.05). We calculated the cut-off tear size for prediction of re-tears as 19.0 mm for retraction and 11.0 mm for superior-inferior. The cut-off Goutallier grade was 2.5 for both whole and upper cross-sections, but area under the curve was greater in the upper cross-section than the whole (0.911 vs. 0.807). Conclusions: As fatty degeneration of upper subscapularis demonstrated a more distinct spectrum than whole subscapularis, we suggest that measuring fatty degeneration of upper subscapularis can be a more useful method to predict clinical prognosis.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• 제8권11호
• /
• pp.3775-3788
• /
• 2014

With the increasing number of the wireless and mobile networks, the way that people use the Internet has changed substantively. Wireless multimedia services, such as wireless video streaming, mobile video game, and mobile voice over IP, will become the main applications of the future wireless Internet. To accommodate the growing volume of wireless data traffic and multimedia services, cognitive radio (CR) and Information-Centric Network (ICN) have been proposed to maximize the utilization of wireless spectrum and improve the network performance. Although CR and ICN have high potential significance for the future wireless Internet, few studies have been conducted on collaborative operations of CR and ICN. Due to the lack of infrastructure support in multi-hop ad hoc CR networks, the problem is more challenging for video streaming services. In this paper, we propose a Cross-layer Video Streaming Mechanism (CLISM) for Cognitive Radio Ad Hoc Information Centric Networks (CRAH-ICNs). The CLISM included two distributed schemes which are designed for the forwarding nodes and receiving nodes in CRAH-ICNs. With the cross-layer approach, the CLISM is able to self-adapt the variation of the link conditions without the central network controller. Experimental results demonstrate that the proposed CLISM efficiently adjust video transmission policy under various network conditions.

• Nuclear Engineering and Technology
• /
• 제10권3호
• /
• pp.145-151
• /
• 1978

D$_2$O에 대한 Butler의 scattering kernel에 관해 조사하였다. 이 kernel을 사용한 전자계산 코드 DEUKER를 개발하였으며 이를 이용하여 산란법칙, 미분산란 단면적 및 전산란 단면적을 계산하였다. D$_2$O 분자내의 어떤 두개 원자간의 산란 영향은 열에너지 영역에서의 산란 중성자 분포를 결정하는데 있어서 중요한 인자가 된다. 따라서 여러 입사 중성자 에너지에 따른 에너지 전달 산란 단면적에 관해 조사하여 이 kernel의 원자로 내의 중성자 분포 계산을 위한 사용 가능성을 연구하였다. 또한 본 연구를 통하여 D$_2$O와 $H_2O$에서의 중성자 산란 과장의 차이점을 밝혔다.

• Structural Engineering and Mechanics
• /
• 제83권1호
• /
• pp.53-66
• /
• 2022

The main objective of the present research was investigating the effects of a floating wave barrier installed in front of an offshore jacket structure on the wave height, base shear, and overturning moment. A jacket model with the height of 4.55 m was fabricated and tested in the 402 m-long wave flume of NIMALA marine laboratory. The jacket was tested at the water depth of 4 m subjected to the random waves with a JONSWAP energy spectrum. Three input wave heights were chosen for the tests: 20 cm, 23 cm, and 28 cm. Two different cross sections with the same area were selected for the wave barrier: square and rhombus. Results showed that the average decrease in the jacket's base shear due to the presence of a floating wave barrier with square and rhombus cross section was 24.67% and 34.29%, respectively. The use of wave barriers with square and rhombus cross sections also resulted in 19.78% and 33.11% decrease in the jacket's overturning moment, respectively. Hence, it can be concluded that a floating wave barrier can significantly reduce the base shear and overturning moment in an offshore jacket structure; and a rhombus cross section is more effective than an equivalent square section.