• Journal of Korean Society of Transportation
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• v.8 no.2
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• pp.119-131
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• 1990

Physico-chemical properties of asphalt, aggregate, and asphalt-aggregate mixture that might influence stripping were summarized in Table 1, based on the fundamental theories concerning stripping. It was found that although physical properties of aggregate affected stripping, there was no strong correlation between the physical properties of aggregate, such as pore volume and surface area, and the stripping propensity of the aggregate. Chemical and electrochemical properties of aggregate surface in the presence of water were most important factors for stripping. All mineral aggregates tested in this study imparted distinctive pH values to the contacting water and possessed distinctive electrochemical properties as measured by zeta potential. It was found that aggregates which had relatively higher surface potential in water and/or which imparted relatively higher pH to the contacting water were more susceptible to stripping. The functionalities contained in antistripping additives tested were primary and secondary amines and those of organic nitrogen compounds. The functionalities were determined by examining their infrared spectra. Based on the interfacial energy concept, the contact angle of an asphalt drop on an aggregate surface immersed in water related to the stripping propensity. The contact angle and stripping propensity were markedly reduced by the presence of an antistripping additive. In general, all the additives tested improved stripping resistance to some extent, depending on their concentration in the asphalts. The optimum dosage of an additive varied with different asphalts, as well as different aggregates. All antistripping additives tested in this study lost their effectiveness and failed to function to some extent when maintained for hours in a hot asphalt.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.865-868
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• 2008

As a part of a series of study, this study reviewed the fire proof characteristics of high performance concrete RC column members using non-stripping form that accompanied metal lath lateral confinement to prevent spalling of high performance concrete which is increasingly used recently, and the results are as follows. Flow and air amount both satisfied target range, and compressive strength, over 80MPa at age 28 days, showed high strength range. As for spalling characteristics, in the case of plain in which no fiber is mixed, severe spalling occurred, and in the case of 0.05% nylon("NY" hereinafter)+polypropylene("PP" hereinafter) fiber mixture, only surface area experienced partial spalling. Regarding non-stripping form changes, both non-stripping 25-20 and non-stripping 50-20 experienced spalling at finish material area, and non-stripping 50-20 showed better spalling proof performance than non-stripping 25-20. In the case of non-stripping 50-40, spalling was prevented, and while mass reduction rate was less than 10%, its temperature hysteresis showed the most excellent fire proof performance with base metal surface area maximum temperature $376.1^{\circ}C$.

• Journal of The Korean Astronomical Society
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• v.54 no.1
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• pp.17-35
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• 2021

We study galaxies undergoing ram pressure stripping in the Virgo cluster to examine whether we can identify any discernible trend in their star formation activity. We first use 48 galaxies undergoing different stages of stripping based on H i morphology, H i deficiency, and relative extent to the stellar disk, from the VIVA survey. We then employ a new scheme for galaxy classification which combines H i mass fractions and locations in projected phase space, resulting in a new sample of 365 galaxies. We utilize a variety of star formation tracers, which include g - r, WISE [3.4]-[12] colors, and starburstiness that are defined by stellar mass and star formation rates to compare the star formation activity of galaxies at different stripping stages. We find no clear evidence for enhancement in the integrated star formation activity of galaxies undergoing early to active stripping. We are instead able to capture the overall quenching of star formation activity with increasing degree of ram pressure stripping, in agreement with previous studies. Our results suggest that if there is any ram pressure stripping induced enhancement, it is at best locally modest, and galaxies undergoing enhancement make up a small fraction of the total sample. Our results also indicate that it is possible to trace galaxies at different stages of stripping with the combination of H i gas content and location in projected phase space, which can be extended to other galaxy clusters that lack high-resolution H i imaging.

• YAKHAK HOEJI
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• v.29 no.3
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• pp.144-151
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• 1985

Cathodic stripping voltammetric determination of traces of selenium in plant samples was studied. Stripping peak of selenium (IV) from Cu-Se intermettalic deposit in acidic media containing copper (II) ion is specific, highly sensitive and well defined, is successfully used for the quantitative determination of selenuin down to the level of 1ng/ml. Sample is burnt in a calorimeter bomb under the oxygen pressure of 40atm. and the selenium is absorbed in 0.1M NaOH. After the solution is filtrated, concentrated and acidified with HCl, then passed through a column of cation exchange resin in the $H^{+}$ form(Dowex 50X-8). The column eluate is analyzed for selenium by differential pulse cathodic stripping voltammetric method. Analytical results of selenium for NBS SMR is well agreement with the certified values. Results are given for a series of plant materials.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.9 no.1
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• pp.111-118
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• 2000

Over tightening experiments of the tension-controlled bolts are carried out and the stripping mechanism is reviewed base on the observed results. There are two modes of bolt failure due to the over tightening : one the fracture of the bolt the other the thread stripping Bifurcation between these two modes is rather delicate but it seems being related with the elastic flexibility of the bolt which depends upon the unused thread length. The fracture mode occurs in the bolts with good flexibility while the latter with bad one. According to the ISO Standard some meter coarse threads like M20 and M22 have the same pitch which causes bigger fastener to less resistance in shear and bending compared with the smaller one. however since UNC thread system adapts different pitch for different nominal diameter unified coarse threads show better stripping resistance than their corresponding meter threads.

• Analytical Science and Technology
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• v.5 no.1
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• pp.17-24
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• 1992

Germanium(IV) was determinated in perchloric acid supporting electrolyte solution containing catechol derivates 3.4-dihydroxy benzoic acid, 3.4-dihydroxy benzaldehyde, adrenaline by hanging mercury electrode(HMDE) of anodic stripping polarography. And then to apply this experimental method for determination of germanium(IV) in natural samples. Germanium(IV) was determinated $300{\mu}g/L$ in ginseng and $210{\mu}g/L$ in mineral water.

• Journal of Chest Surgery
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• v.48 no.6
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• pp.398-403
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• 2015

Background: The aim of this study was to evaluate the midterm clinical outcomes after modified high ligation and segmental stripping of small saphenous vein (SSV) varicosities. Methods: Between January 2010 and March 2013, 62 patients (69 legs) with isolated primary small saphenous varicose veins were enrolled in this study. The outcomes measured were reflux in the remaining distal SSV, the recurrence of varicose veins, the improvement of preoperative symptoms, and the rate of postoperative complications. Results: No major complications occurred. No instances of the recurrence of varicose veins at previous stripping sites were noted. Three legs (4.3%) showed reflux in the remaining distal small saphenous veins. The preoperative symptoms were found to have improved in 96.4% of the cases. Conclusion: In the absence of flush ligation of the saphenopopliteal junction, modified high ligation and segmental stripping of small saphenous vein varicosities with preoperative duplex marking is an effective treatment method for reducing postoperative complications and the recurrence of SSV incompetence.

• The Bulletin of The Korean Astronomical Society
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• v.42 no.2
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• pp.75.3-75.3
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• 2017

We Investigate dust stripping of Virgo cluster galaxies that are known to suffer HI gas stripping. The gas stripping phenomena of these galaxies may result from either ram pressure induced by the hot intracluster medium or gravitational tidal interactions between galaxies. While much efforts have been made to directly detect gas removed from cluster galaxies, the spatial distributions of dust, which should also be affected, are hardly known. Several previous studies have tried to directly detect the morphology of gas or dust using radio or infrared observations, but such approaches are hard to widely apply because of the limit of observational resolution and sensitivity. In this study, we try a different approach using optical data: measuring the background galaxy reddening by the dust stripped from the Virgo cluster members. Based on optical color excess maps of the background galaxies, we compare the ambient dust distribution with the HI morphology of the Virgo galaxies. We discuss how efficiently dust stripping can be detected with this method and how the stripped dust is associated with the removed gas according to HI gas stripping stage over the sample.

• Journal of Industrial Technology
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• v.26 no.B
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• pp.35-41
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• 2006

Recently, as ultrasonic medical devices are gradually developed, many of those requires smaller and more precision coaxial cables in probe. So, the use of micro coaxial cable becomes an efficient solution for ultrasonic machine. However, there are many difficulties in stripping micro coaxial cable by traditional mechanical process. In this paper, we use the Nd-YAG laser for the efficient stripping of conduct wire of cable. We propose a new method to strip the shield wire of micro coaxial cable. Through some experiments, we found that there is a new possibility in the proposed method. Also, in order to enhance the performance, we propose a preprocess of the cable before stripping.

• The Bulletin of The Korean Astronomical Society
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• v.44 no.1
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• pp.75.3-75.3
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• 2019

Understanding how ram pressure stripping (RPS) affects the star formation activity of cluster galaxies is one of the important issues in astrophysics. To examine whether we can identify any discernible trend in the star formation activity of galaxies undergoing ram pressure stripping, we study the star formation properties of galaxies in the Virgo cluster for which high-resolution HI images are available. We first classify galaxies in the Extended Virgo Cluster Catalog into different stages of RPS based on their HI morphology, HI deficiency, and location in phase space. We then examine various star formation activity indicators of these galaxies, which include starburstiness, g - r color, and WISE [3.4]-[12] color. No noticeable enhancement in star formation was identified for galaxies undergoing early or active stripping. Our results suggest that star formation activity at best seems to be enhanced locally in such galaxies, making it challenging to detect with integrated photometry. With the combination of HI deficiencies and locations in phase space, we were instead able to capture the overall quenching of star formation activity with increasing degree of ram pressure stripping, which agree with previous studies.