• Title/Summary/Keyword: RAD

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Approaching Green Buildings Using Eco-Efficient Construction Materials: A Review of the state-of-the-art

  • Aghdam, Karim Aligholizadeh;Rad, Alireza Foroughi;Shakeri, Hamed;Sardroud, Javad Majrouhi
    • Journal of Construction Engineering and Project Management
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    • v.8 no.3
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    • pp.1-23
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    • 2018
  • Since the protection the of human being from natural disaster and atmospheric factors have become an essential requirement, some attempts have been taken place to provide shelter and create a safe environment to a more comfortable life with welfare. For this purpose, using existing resources in nature and exploiting them in a different manner have been taken into account. Initially, the performed exploitations for construction had the least damage to the environment, but over time and as a result of population growth, aggressive exploitation of nature has led to destroying effects on the environment and resulted in consequences such as pollution and environmental destruction. Thus, the construction industry has been identified as the top pollutant factors of the environment. Among various construction factors, the building materials used in this industry are considered as the most important effective factors on the environment, as they have direct influences on the environment from the beginning of construction of the final steps. This research focuses on the review of the most of the existing green materials definitions and various approaches towards using eco-efficient construction materials. It presents and discusses possible ways of reducing the destructive effects on the environment by selecting and using green materials, review current literature and highlight the necessity of applying such materials in future constructions in all communities. This paper provides a base for this purpose that sustainable development communities and environment is realized by elimination of environmental pollution and approaching the criteria of green building by using sustainable materials.

Modification of PLA by Irradiation of Electron Beam in the Presence of Functional Monomer: Rheological and Thermal Properties (기능성 단량체를 함유한 PLA의 전자선 조사에 의한 개질: 유변학적 성질 및 열적 특성)

  • Kang, Kyoung Soo;Shin, Boo Young
    • Korean Chemical Engineering Research
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    • v.46 no.1
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    • pp.124-130
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    • 2008
  • In order to fabricate a modified poly (lactic acid) (PLA) for applications requiring high melt strength, a PLA has been irradiated in the presence of functional monomer of glycidyl methacrylate (GMA). Samples were prepared with various contents of GMA and irradiation dosages, and were characterized by observing their thermal and melt viscoelastic properties and gel faction. The complex viscosity and storage modulus of the modified PLA without GMA were lower than those of the original PLA. Those of the modified PLA decreased with increasing dosage. In the case of the modified PLA containing 0.1 phr or 0.3 phr of GMA, their changing tendency with dosage was similar to the irradiated PLA without GMA. However, the 5 kGy irradiated PLA containing 0.5 phr of GMA showed the greatly enhanced complex viscosity and storage modulus, which were about 3 and 10 times higher than those of the original PLA at a frequency of 0.1 rad/s, respectively.

Comparing Biological Markers of Alcohol Dependence in the Patients of an Alcohol Counseling Center (알코올 상담 센터 환자를 대상으로 한 알코올 의존의 생물학적 표지자 비교 연구)

  • Byun, Jung-Hyun;Lee, Boung-Chul;Ham, Byung-Joo;Chung, Chan Seung;Hur, Mina;Lee, Jung-Joon;Choi, Ihn-Geun
    • Korean Journal of Biological Psychiatry
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    • v.13 no.4
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    • pp.273-278
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    • 2006
  • Objectives : Biochemical markers can provide an objective evidence of heavy alcohol drinking. The purpose of this study was to compare and evaluate the usefulness of biological markers detecting alcohol dependence, such as mean corpuscular volume(MCV), gamma-glutamyl transferase(GGT), and carbohydrate-deficient transferrin(CDT) in the patients of an alcohol counseling center. Methods : This study was done with 64 patients with alcohol dependence and 36 healthy subjects. Relative values(%) of CDT were determined in their sera with turbidimetric immunoassay(Bio-Rad %CDT assay, Axis-Shield ASA, Oslo, Norway), and were compared with conventional markers of alcohol consumption, GGT and MCV. Results : Among the patients with alcohol dependence, 78.1% showed abnormal %CDT levels compared with GGT(61.9%) and MCV(20.7%). The areas under the receiver operating characteristic(ROC) curves(95% confidence interval) for %CDT, GGT, and MCV were 0.934(0.866-0.973), 0.871(0.789-0.930), and 0.575 (0.472-0.673), respectively. Conclusion : %CDT seems to be the most reliable biological marker for the detection and monitoring of alcohol consumption in the patients with alcohol dependence of the alcohol counseling center.

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Effects of demi-hull separation ratios on motion responses of tidal current turbines-loaded catamaran

  • Junianto, Sony;Mukhtasor, Mukhtasor;Prastianto, Rudi Walujo;Jo, Chul Hee
    • Ocean Systems Engineering
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    • v.10 no.1
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    • pp.87-110
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    • 2020
  • Catamaran has recently been a choice to support a typical vertical axis turbine in floating tidal current energy conversion system. However, motion responses associated with the catamaran can reduce the turbines efficiency. The possibility to overcome this problem isto change the catamaran parameter by varying and simulating the demi-hull separations to have lower motion responses. This simulation was undertaken by Computational Fluid Dynamic (CFD) using potential flow analysis. Cases of demi-hull separation were considered, with ratios of demi-hull separation (S) to the breadth of demi-hull (B), S/B of 3.45, 4.95, 6.45, 7.2 and 7.95. In order to compare to the previous works in the literature, the regular wave was set with wave height of 0.8 m. Furthermore, the analysis was carried out by irregular waves with significant wave height, Hs, of about 0.09 to 1.5 m and the wave period, T, of about 1.5 to 6 s or corresponding to the wave frequency, ω, of about 1.1 to 4.2 rad/s. The wave spectrum was derived from the equation of the International Towing Tank Conference (ITTC). For the case of turbines-loaded catamaran under consideration, the new finding is that the least significant amplitude response can be satisfied at the ratio S/B of 7.2. This study indicates that selecting a right choice of demi-hull separation ratio could contribute in reducing motion responses of the tidal current turbines-loaded catamaran.

Concentrations of Bioavailable Testosterone and Dihydrotestosterone Determined by Luminescence Immunoassay in Serum (혈청내 섬광면역측정법에 의한 활성적 Testosterone과 Dihydrotestosterone의 농도)

  • Yoon, Yong-Dal;Lee, Chang-Joo;Chun, Eun-Hyun;Lee, Joon-Yeong
    • Clinical and Experimental Reproductive Medicine
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    • v.15 no.2
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    • pp.83-92
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    • 1988
  • 혈액에서 생물학적 활성을 나타내는 (bioavailable) steroid hormone은 주로 비결합형(free form)과 알부민 결합형(albumin-bound form)으로 구성된다. 특히 Testosterone (T)과 5 alpha-Dihydrotestosterone (DHT)의 활성적 분획이 전체의 T, DHT 양에 비해 생리적 현상과 보다 잘 일치하는 것으로 알려지고 있다. 본 연구는 섬광면역측정법(Luminescence immunoassay, LIA)으로 혈청내 활성적 T 및 DHT의 농도의 측정에 이용하고져 하였다. 항체는 T- 또는 DHT-3-CMO-BSA를 항원으로 토끼에 면역주사하여 얻었다. 추적자는 T-3-CMO, DHT-3-CMO에 aminobutylethylisoluminol(ABEI)를 부착시켜 사용하였다. 항체중 IgG분획을 Protein-A-Sepharose CL-4B로 분리한 후 Immunobead(Bio-Rad)에 부착시켜 Solid-phase LIA를 실시하였다. 본 연구에서 LIA는 정확도(accuracy), 정밀도(precision), 감도(sensitivity), 교차반응도(specificity)등을 조사하고, 기존의 방사면역측정법(RIA)과 비교하여 만족할만한 결과를 얻었다. 혈청내 T및 DHT의 활성적 분획의 농도를 측정한 결과는 다음과 같았다. T의 경우는 남성에서 T의 전체량의 33% 이상으로 $7.1{\pm}1.5nmol/l$, 여성에서는 26% 이상으로 $0.28{\pm}0.05nmol/l$이었다. DHT의 활성적 분획은 남성의 경우 $601.7{\pm}85.8pmol/l$, 여성의경우 $52.4{\pm}19.9\;pmol/l$이었다. 이상의 결과를 보아 본 연구에서 이용된 LIA는 혈청내 활성적 농도를 측정하기에 충분하다고 사료된다. 또한 이 방법을 이용하여 여성의 Androgenicity 및 남성 정소기능등의 제어방법에 응용될 수 있을 것으로 판단된다.

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Study on Stable Fly Eradication by Sterile-male Technique (4) Effects of X-ray Irradiation on the Stable Fly (웅성불임기술을 이용한 쇠파리 구제에 관한 연구 (4) 방사선 조사가 쇠파리에 미치는 영향)

  • Chung K. H.;Ryu J.;Kwon S. H.
    • Korean journal of applied entomology
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    • v.14 no.3 s.24
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    • pp.163-166
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    • 1975
  • This experiment was performed to investigate the X-ray sensitivities at the various stages of life cycle and to determine the sterillizing dose of stable fly, Stomoxys calcitrans(L). A dose of 300 rad caused about $50\%$ mortality in 2-hour-old eggs as measured by egg hatch, and $100\%$ mortality was obtained with a does of 1 Krad. Sub-lethal dose $(LD_{50})$ for the pupal mortality after irradiation of 3-5days old pupae were 11.5 Krad and the mortality was decreased with increasing pupal age at irradition. A significant reduction of egg hatch by $1.5\%$ was observed when treated males with 3 Krad at pupal stage were mated to untreated virgin femleas. On the other hand, $100\%$ sterility in females was resulted by 2 Krad irradiation and oviposition was completely inhibited with 3 Krad. Thus, both sexes of stable fly could be sterilized with a dose of 4 Krad irradiated to 3-5 days old pupae.

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IRRADIATION EFFECT ON SECRETING FUNCTION, AMYLASE ACTIVITY AND NUCLEIC ACID CONTENTS OF RAT PAROTID GLAND (방사선 조사가 이하선 기능에 미치는 영향에 관한 연구)

  • Cho Yong Jin;Park Tae-Won
    • Journal of Korean Academy of Oral and Maxillofacial Radiology
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    • v.20 no.1
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    • pp.53-62
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    • 1990
  • This experiment was performed to clarify the effects of /sup 60/Co gamma irradiation on secretory function, amylase activity and contents of nucleic acids of parotid gland in rat. Experimental animals were divided into 6th hours, 3rd, 7th, 14th and 28th days after irradiation and control. The experimental animals are singly irradiated with 20Gy (2,000rad) through protective lead block. Secretory function of parotid gland was evaluted by uptake and clearance of /sup 99m/TcO₄. /sup 99m/TcO₄. 0.2μ ci/gm, was injected into peritonium in uptake groups. Rats were sacrified with cervical dislocation after 30 minutes and gland was excised. In the clearance group. pilocarpine nitrate (8㎎/㎏) was intraperitoneally injected at 30 minutes after /sup 99m/TcO₄ injection and rats were sacrified 30 minutes after pilocarpine injection. Radioactivity of excised parotid gland was measured by using of gamma counter and stimulation-secretion coefficients, uptake radioactivity divided by clearance radioactivity, was calculated. Amylase activity and contents of DNA and RNA were determined by spectrophotometry. The results obtained were as follows: 1. In the uptake test, the radioactivity of /sup 99m/TcO₄ per unit weight increase in experimental group except 6th hours group, compared with control groups and showed a peak at 3rd days after irradiation. 2. In the clearance test, the radioactivity of /sup 99m/cO₄per unit weight rose to a peak at 3rd days after irradiation and gradually recovered thereafter. 3. Stimulation-secretion coefficient of parotid gland decreased at 6th hours, 3rd and 7th days after irradiation, and gradually increased. 4. Amylase activity of parotid gland decreased in 3rd and 7th days group, and especially lowest in 3rd days after irradiation. 5. The contents of DNA showed no definite difference in all the experimental groups, but RNA was seemed to decrease with time after irradiation.

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Forbush Decreases Observed by the LRO/CRaTER

  • Sohn, Jongdae;Oh, Suyeon;Yi, Yu;Kim, Eojin;Lee, Joo-Hee;Spence, Harlan E.
    • The Bulletin of The Korean Astronomical Society
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    • v.37 no.2
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    • pp.120.1-120.1
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    • 2012
  • The Lunar Reconnaissance Orbiter (LRO) launched on June 16, 2009 has six experiments including of the Cosmic Ray Telescope for the Effects of Radiation (CRaTER) onboard. The CRaTER instrument characterizes the radiation environment to be experienced by humans during future lunar missions. The CRaTER instrument measures the effects of ionizing energy loss in matter specifically in silicon solid-state detectors due to penetrating solar energetic protons (SEP) and galactic cosmic rays (GCRs) after interactions with tissue-equivalent plastic (TEP), a synthetic analog of human tissue. The CRaTER instrument houses a compact and highly precise microdosimeter. It measures dose rates below one micro-Rad/sec in silicon in lunar radiation environment. Forbush decrease (FD) event is the sudden decrease of GCR flux. We use the data of cosmic ray and dose rates observed by the CRaTER instrument. We also use the CME list of STEREO SECCHI inner, outer coronagraph and the interplanetary CME data of the ACE/MAG instrument.We examine the origins and the characteristics of the FD-like events in lunar radiation environment. We also compare these events with the FD events on the Earth. We find that whenever the FD events are recorded at ground Neutron Monitor stations, the FD-like events also occur on the lunar environments. The flux variation amplitude of FD-like events on the Moon is approximately two times larger than that of FD events on the Earth. We compare time profiles of GCR flux with of the dose rate of FD-like events in the lunar environment. We figure out that the distinct FD-like events correspond to dose rate events in the CRaTER on lunar environment during the event period.

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Indoor radon and thoron from building materials: Analysis of humidity, air exchange rate, and dose assessment

  • Syuryavin, Ahmad Ciptadi;Park, Seongjin;Nirwono, Muttaqin Margo;Lee, Sang Hoon
    • Nuclear Engineering and Technology
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    • v.52 no.10
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    • pp.2370-2378
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    • 2020
  • Building materials contribute significantly to the indoor radon and thoron levels. Therefore, parameters that influence the exhalation rates of radon and thoron from building material need to be analyzed closely. As a preliminary study, the effects of humidity on exhalation rates were measured using a system with an accumulation chamber and RAD7 detector for Korean brick, Korean soil, and Indonesian brick. Resulting doses to a person who resides in a room constructed from the building materials were assessed by UNSCEAR method for different air exchange rates. The measurements have revealed that Korean brick exhaled the highest radon and thoron while Indonesian brick exhaled the lowest thoron. Results showed that for a typical low dense material, radon and thoron exhalation rate will increase until reached its maximum at a certain value of humidity and will remain saturated above it. Analysis on concentration and effective dose showed that radon is strongly affected by air exchange rate (ACH). This is showed by about 66 times decrease of radon dose from 0.00 h-1 to those of 0.50 h-1 ACH and decrease by a factor of 2 from 0.50 h-1 to those of 0.80 h-1. In case of thoron, the ACH doesn't have significant effects on effective dose.

A femtosecond Cr:LiSAF laser pumped by semiconductor lasers (반도체 레이저 여기 펨토초 Cr:LiSAF 레이저)

  • 박종대
    • Korean Journal of Optics and Photonics
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    • v.11 no.5
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    • pp.360-364
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    • 2000
  • We demonstrate self-starting passIve mode locking of a Cr:LiSAF laser, using a SCIDlconduclor Saturable Absorber Mirror (SESAM), Two high-power red semiconductor lasers (Coherent S-67-500C-100-H) of wavelength 667 nm and maximum power of 500 mW were used as pump lasers, The cavity has 10 cm radius-ai-curvature folding minors, two SF 10 prisms, a 99% reflectivity output coupler and a SESAM at dIe focus of a 10 cm radIus-at-curvature mirror. We used the laser crystal in BrewsterBrewster shape with 1 5% $Cr^{+3}$ ion concentration and the length of 6 mm, An X-shaped resonator was used to compensate the astigmatism induced by tile crystal. The structure of the SESAM cOllSists of 30 pmr of $AlAs/Al_{0.15}Ga_{0.85}As$ layer, wi1l1 a 10 nm GaAs quantum well situated in the topmost layer Output spectra were centeled at 833 nm, with 4 nm spectral bandwidth and pulse width was measured to be 220 fs, Output power of 3 mW is obtained at a pump power of 800 mW. 00 mW.

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