• Journal of Photoscience
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• 제9권2호
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• pp.436-438
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• 2002

Since solar radiation contains wavelength essential for photosynthesis accompanying with near-UV light, UV-B effects on biological parameters and acclimation mechanisms are influenced by photosynthetically active radiation (PAR). Therefore, to elucidate near-UV shielding mechanism in higher plants, we cultivated cauliflower under usual solar radiation and increased UV-B from fluorescent lamps, two- or three-fold excess over continuously estimated UV-B dose in PAR during daytime, using computer regulated systems. Increased UV-B radiation had little effect on growth expressed as fresh weigh and leaf area. Water soluble low molecular weight compounds showing absorption in near UV region were enhanced according to the irradiated UV-B dose. One of compounds in cauliflower leaves was identified as chlorogenic acid. This was found to have no near-UV photosenSitizerable activity and is known to have an ability to scavenge a wide species of active oxygen. Another pro-oxidant compound that generates superoxide anion radical under near-UV irradiation was not induced by increased UV-B during cultivation, and identified as lumazine, a degradation product from folic acid.

• Earthquakes and Structures
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• 제15권5호
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• pp.487-498
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• 2018

Buckling-restrained braces are passive control devices with high level of energy dissipation ability. However, they suffer from low post-yield stiffness which makes them vulnerable to severe ground motions, especially near-field earthquakes. Among the several methods proposed to improve resistance of BRB frames, mega-brace configuration can be a solution to increase frame lateral strength and stiffness and improve distribution of forces to prevent large displacement in braces. Due to the limited number of research regarding the performance of such systems, the current paper aims to assess seismic performance of BRB frames with mega-bracing arrangement under near-field earthquakes via a detailed probabilistic framework. For this purpose, a group of multi-story mega-BRB frames were modelled by OpenSEES software platform. In the first part of the paper, simplified procedures including nonlinear pushover and Incremental Dynamic Analysis were conducted for performance evaluation. Two groups of near-fault seismic ground motions (Non-pulse and Pulse-like records) were considered for analyses to take into account the effects of record-to-record uncertainties, as well as forward directivity on the results. In the second part, seismic reliability analyses are conducted in the context of performance based earthquake engineering. Two widely-known EDP-based and IM-based probabilistic frameworks are employed to estimate collapse potential of the structures. Results show that all the structures can successfully tolerate near-field earthquakes with a high level of confidence level. Therefore, mega-bracing configuration can be an effective alternative to conventional BRB bracing to withstand near-field earthquakes.

• Earthquakes and Structures
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• 제19권3호
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• pp.189-196
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• 2020

The near-collapse performance limit is defined as the deformation at the 20% drop of maximum base shear in the decreasing region of the pushover curve for ductile framed buildings. Although monotonic pushover analysis is preferred due to the simple application procedure, this analysis gives rise to overestimated results by neglecting the cumulative damage effects. In the present study, the acceptabilities of monotonic and cyclic pushover analysis results for the near-collapse performance limit state are determined by comparing with Incremental Dynamic Analysis (IDA) results for a 5-story Reinforced Concrete framed building. IDA is performed to obtain the collapse point, and the near-collapse drift ratios for monotonic and cyclic pushover analysis methods are obtained separately. These two alternative drift ratios are compared with the collapse drift ratio. The correlations of the maximum tensile and compression strain at the base columns and beam plastic rotations with interstory drift ratios are acquired using the nonlinear time history analysis results by the simple linear regression analyses. It is seen that these parameters are highly correlated with the interstory drift ratios, and the results reveal that the near-collapse point acquired by monotonic pushover analysis causes unacceptably high tensile and compression strains at the base columns, as well as large plastic rotations at the beams. However, it is shown that the results of cyclic pushover analysis are acceptable for the near-collapse performance limit state.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume I
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• pp.495-498
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• 2006

Optical profile and spectral absorption of suspended solids in waters of Sanya bay was measured on August 8-14, 2003. Optical profile was taken by using MicroPro optical profile. Apparent optical indexes, vertical diffuse attenuation coefficient ($K_d$) and water leaving radiance (Lw), were calculated. $K_d$ at the blue end of the spectrum was greater than that at the red end of the spectrum in waters near Sanya River mouth, however, in waters near open sea, $K_d$ at the blue end of the spectrum was smaller than that at the red end of the spectrum. Distribution of water leaving radiance was relatively higher in waters near Sanya River mouth, but relatively weaker in near open sea water. Spectral absorption of suspended particulates was also measured. Results showed that the spectral absorption of chlorophyll a was greater in waters near Sanya river mouth, but relatively weaker in waters near open sea, which indicated higher concentration of phytoplankton in waters near Sanya river mouth. Except for water at the 5th sampling station, the ratio of spectral absorption of chlorophyll a to total suspended particulates in surface waters was greater than that in bottom waters at all stations.

• 대한가정학회지
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• 제18권4호
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• pp.31-39
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• 1980

The basic pattern of skirt should be functional in addition to be fit the body. The author paid special attention to the expansion and contraction of the shell which were made the lower trunk and thigh caused by sitting motions. The replicas of the shell were taken by using a gypsum method on 1 female under 4 standardized motions; standing motion, (basic motion), sitting on the chair with flextion 90' at the hip and the knee joints sitting with dropping knees, and sitting with benting legs side wards. Those replicas obtained were developed to the patterns and changes in shape and area of those were measured. Typical displacement and transformation of the shell surface patterns were showed geographycally fig 5-1 to 5-4. mean values of expansion and constriction were obtained by measuring the shell surface on 60 female under the 4 motions. the mean values of it were showed numerically in Table 1-1 to 1-3. The following results were obtained; 1. Vertical constriction of front of the shell were observed near sulcus in guinalis, and vertical extension were near the knees. Horizontal extension were observed near the thighs and the knees. 2. Vertical constrictions of the back of the shell were observed near the knees. It seemed to be influnced the flexion angles of knee points. vertical extension were near gluteus and thighs. Horizontal constriction were small, and horizonlal extension were near gluteus. 3. The high rates of constriction and extension were found near sulcus in guinalis, glutes, and knees. 4. The rates of constriction and extension on the waist line were very low. 5. The highest values of constriction and extension were found in hip and knees.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 춘계학술대회
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• pp.1795-1800
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• 2003

An experimental study was carried out to investigate near-wake characteristics of an elliptic airfoil oscillating in pitch. The airfoil was sinusoidally pitched about the half chord point between $-5^{\circ}C$ and $+25^{\circ}C$ angles of attack at the freestream velocities of 3.4 and 23.1 m/s The corresponding Reynolds numbers based on the chord length were $3.3{\times}10^4$ and $2.2{\times}10^5$, respectively. A hot-wire anemometer was used to measure the near-wake flow variable at the reduced frequency of 0.1. Ensemble-averaged velocity and turbulence intensity profile were presented to examine the near-wake characteristics depending on the Reynolds number. The axial velocity deficit in the near-wake region tend to decrease with the increase in the Reynolds number a found in many stationary airfoil test . Turbulence intensity in the near-wake region have a tendency to decrease with the increase in the Reynolds number during the pitch-up motion, whereas it shows different feature during the pitch-down motion either the laminar boundary layer or turbulent boundary layer separation.

• Earthquakes and Structures
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• 제7권6호
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• pp.1259-1281
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• 2014

This research has been conducted in order to investigate the effects of peak ground velocity (PGV) of near-field earthquakes on base-isolated structures mounted on Single Friction Pendulum (SFP), Double Concave Friction Pendulum (DCFP) and Triple Concave Friction Pendulum (TCFP) bearings. Seismic responses of base-isolated structures subjected to simplified near field pulses including the forward directivity and the fling step pulses are considered in this study. Behaviour of a two dimensional single story structure mounting on SFP, DCFP and TCFP isolators investigated employing a variety range of isolators and the velocity (PGV) of the forward directivity and the fling step pulses as the main variables of the near field earthquakes. The maximum isolator displacement and base shear are selected as main seismic responses. Peak seismic responses of different isolator types are compared to emphasize the efficiency of each one under near field earthquakes. It is demonstrated that rising the PGVs increases the isolator displacement and base shear of structure. The effects of the forward directivity are greater than the fling step pulses. Furthermore, TCFP isolator is more effective to control the near field effects than the other friction pendulum isolators are. This efficiency is more significant in pulses with longer period and greater PGVs.

• 한국강구조학회 논문집
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• 제28권4호
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• pp.271-280
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• 2016

근접거리에서의 폭발하중의 정확한 정량화에 대한 요구는 주요기반시설물, 빌딩 및 교량의 안전설계가 근접폭발에 대한 것이라는 점에서 매우 중요하다. 근접폭발에 대한 입사 및 반사압력은 높은 압력과 온도로 인하여 사용가능한 압력변환기로는 직접적인 측정이 매우 힘들며, 이는 근접거리에서의 압력과 충격량에 대한 합당한 예측을 가능하게 하는 확인되고 검증된 전산유체역학코드를 필요로 한다. 본 논문은 입사 및 반사 초과압력 및 충격량의 산정에 대하여 CFD 코드를 확인하고 증명하기 위한 수치해석에 대하여 소개하였다. 연구는 근접거리에 초점을 맞추어 수행되었으며, 근접폭발 시뮬레이션을 최적화하는 메쉬크기에 대에 대해서도 제안하였다.

• 천문학회보
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• 제35권1호
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• pp.54.2-54.2
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• 2010

The most massive galactic globular cluster, $\omega$ Cen has been observed using recently mounted WFC3/UVIS cameras of Hubble Space Telescope at both near-UV and optical bands. We present the photometry of stars in the central region of $\omega$ Cen in F225W, F275W and F336W bands. The near-UV color-magnitude diagrams and color-color diagrams of stars in $\omega$ Cen show multiple red giant branches and main sequences as already discovered in both ground-based and HST/ACS observations in the optical bands. We modelled the stellar populations of $\omega$ Cen using Yonsei Isochrone, where $\alpha$-particles and helium enhancement processes have been included properly. We compare the best-fit stellar populations obtained from the current near-UV observations to the suggested stellar population models based on optical band data. We also discuss the methodological issues arising when dealing with the near-UV observations; red-leak in near-UV filters and the huge interstellar extinction in near-UV bands compared to the optical bands and its non-linear effect in color-magnitude diagrams.

• 중환자간호학회지
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• 제13권3호
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• pp.1-10
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• 2020

Purpose : This study aims to investigate the differences in fatigue, sleepiness, and near-miss according to sleep disturbance among shift nurses in intensive care units (ICUs). Methods : A cross-sectional study in a tertiary hospital was performed. A total of 122 shift nurses working in the six ICUs were recruited. They completed self-reported questionnaires about sleep disturbance, fatigue, sleepiness, and near-miss in the past two weeks. Results : The prevalence of reported sleep disturbance was 30.3% (37 out of 122 subjects). Compared to the non-sleep disturbance group, the sleep disturbance group reported significantly more sleepiness (11.46 vs. 8.86) and higher fatigue (82.62 vs. 69.39). The sleep disturbance group showed higher rates of near-miss (78.4 vs. 57.6%) and a higher frequency of them (4.49 vs. 2.11/2weeks) compared to the non-sleep disturbance group. Medication error was the most common type of near-miss. Conclusions : This study suggests that sleep disturbances could increase fatigue, sleepiness, and near-miss among ICU shift nurses. Personal and organizational programs should be developed to support the sleep of ICU nurses.