• Title/Summary/Keyword: control surface damage

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A Study on the Improvement of Security Enhancement for ZTNA (보안성 강화를 위한 ZTNA운영 개선방안 연구)

  • Seung Jae Yoo
    • Convergence Security Journal
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    • v.24 no.1
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    • pp.21-26
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    • 2024
  • The security model in the previous network environment has a vulnerability in which resource access control for trusted users is not properly achieved using the Perimeter model based on trust. The Zero Trust is an absolute principle to assume that the users and devices accessing internal data have nothing to trust. Applying the Zero Trust principle is very successful in reducing the attack surface of an organization, and by using the Zero Trust, it is possible to minimize damage when an attack occurs by limiting the intrusion to one small area through segmentation. ZTNA is a major technology that enables organizations to implement Zero Trust security, and similar to Software Defined Boundary (SDP), ZTNA hides most of its infrastructure and services, establishing one-to-one encrypted connections between devices and the resources they need. In this study, we review the functions and requirements that become the principles of the ZTNA architecture, and also study the security requirements and additional considerations according to the construction and operation of the ZTNA solution.

Beneficial Effect of Hyangsayangwi-tang on the Cisplatin-Induced Gastrointestinal Dysfunctions in Rats (향사양위탕이 시스플라틴 유발 랫트의 위장관 기능 장애에 미치는 영향)

  • Seo, Eun-Hee;Kim, Seong-Tae;Bae, Na-Young;Choi, Ae-Ryun
    • Journal of Sasang Constitutional Medicine
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    • v.25 no.4
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    • pp.343-358
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    • 2013
  • Objectives This study aimed to observe the effect of Hyangsayangwi-tang on the cisplatin-induced gastrointestinal dysfunctions in rats. Methods Four groups(each of 8 rats per group) were used in this study. Saline and distilled water treated control rats are Intact vehicle control group. Delayed gatrointestinal mortility was induced by intraperitoneal treatment of cisplatin 2mg/kg, once a week for 5 weeks(Cisplatin control group). Hyangsayangwi-tang aqueous extracts(HY) were orally administered in a volume of 5ml/kg, once a day for 14 days from 4th ciplatin treatmernt(HY group). Ondansetron 1mg/kg was subcutaneously treated, in a volume of 1ml/kg, as same as HY(ondansetron group). We measured the body weights, intestinal charcoal transit ratio, fecal parameters, fundus MDA, GSH contents and SOD, CAT activities, TPH and MAO activities, pyloric gastrin and serotonin contents with their immunoraective cells, colonic serotonin-immunoreactive cells, the histopathology of pylorus, fundus mucosa and colon. Results and Conclusions (1) The body weight gains, the small intestinal charcoal transfer rates, the fecal parameters(numbers, weights and water contents) were increased in HY, ondansetron group. (2) The inhibit of fundus antioxidant defense systems by cisplatin were decreased in HY, ondansetron group. (3) The pyloric TPH activities were increased and the pyloric MAO activities were decreased in HY group. (4) The pyloric gastric contents and the gastrin-immunoreactive cells were increased in HY group. And the pyloric serotonin contents and the pyloric and colonic serotonin-immunoreactive cells were decreased in HY group. (5) The pyloru atrophic changes and the gastric surface erosive damage regions by cisplatin were favorably inhibited by treatment of HY. HY, a representative Soeumin prescription improve GI dysfunctions and constipation retarded by cisplatin through modulations of GI enterochromaffin cells, serotonin and gastrin-producing cells and antioxidative systems. Especially HY showed the highest favorable effects more than those of ondansetron.

Study on Hot Water Immersion Treatment for Control of Meloidogyne spp. and Pratylenchus spp. in a Ginger, Zingiber officinale (생강에서 뿌리혹선충과 뿌리썩이선충의 사멸을 위한 온탕침지처리 연구)

  • Cho, Donghun;Park, Kyonam;Kim, Yangho;Koh, Kyung-bong;Park, Youngjin
    • Korean journal of applied entomology
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    • v.56 no.2
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    • pp.171-177
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    • 2017
  • Plant parasitic nematodes, Meloidogyne and Pratylenchus spp., are mostly detected in imported bulbs and tubers including a ginger, Zingiber officinale in Korea by quarantine inspection. However, there is little information on hot water immersion treatment (HWIT) for control of exotic nematodes, which induce economic loss by discard or send back to exporter, in imported gingers. In here, we determined that mortality of two plant parasitic nematodes and thermal stability of ginger. Meloidogyne and Pratylenchus spp. were completely killed at $48^{\circ}C$ and $49^{\circ}C$ for 30 sec by HWIT. Thermal conduction of Z. officinale to reach a target temperature as $50^{\circ}C$ take 10~32 min and 6~16 min for core and inner 5 mm region from surface, respectively. When ginger exposed at $51^{\circ}C$ for 30 min, growth of Z. officinale was not affected by heat treatment compared with control. Based on these results, HWIT at $51^{\circ}C$ for 30 min completely killed artificially infected juveniles of Meloidogyne spp. in Z. officinale. Therefore, this condition for HWIT will be used as fundamental information on phytosanitory to kill two plant parasitic nematodes without damage on ginger.

Effect of Taxol Pre-treatment to In Vitro Matured Bovine Oocytes on Spindle Morphology and Embryonic Development Following Vitrification

  • Park, Sang-Hyoun;Yu, Il-Jeoung
    • Journal of Embryo Transfer
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    • v.23 no.4
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    • pp.269-274
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    • 2008
  • The purpose of this study was to determine the effects of Taxol pre-treatment to in vitro matured bovine oocytes, and sucrose and trehalose added to vitrification solution on spindle morphology and embryonic development following cryopreservation. Bovine oocytes were collected from ovaries and matured in tissue culture medium 199 (TCM 199) supplemented with 10% Fetal Bovine Serum (FBS), 0.05ng/ml epidermal growth factor, 0.01 IU/ml luteinizing hormone and $1{\mu}g/ml$ estradiol for 22h in $39^{\circ}C$, 5% $CO_2$, TCM 199-HEPES containing 20% FBS was used as basic medium (BM) to prepare vitrification solution. Oocytes were pre-treated with $1\;{\mu}M$ Taxol in maturation medium for 15 min prior to vitrification. Oocytes were exposed to 1.6 M ethylene glycol (EG) and 1.3M dimethyl sulfoxide (DMSO) in BM and then were exposed to 3.2 M EG, 2.6 M DMSO and 0.5 M sucrose in BM or 3.2 M EG, 2.6 M DMSO and 0.5 M trehalose in BM. Oocytes with cumulus cells and oocytes without cumulus cells were considered as control 1 and control 2, respectively and held in TCM 199-HEPES at $39^{\circ}C$. Oocytes were frozen using modified solid surface vitrification and were stored in cryotubes in liquid nitrogen for more than 1 week. Frozen oocytes were thawed in TCM 199-HEPES containing 0.5 M, 0.25 M and 0.1 M sucrose in BM for 2 min, respectively or 0.5 M, 0.25 M and 0.1 M trehalose in BM for 2 min, respectively. Immunoflurorescence staining of oocytes was performed to assess spindle morphology and chromosome configuration of oocytes. The rates of cleavage and blastocyst were examined following in vitro fertilization. Normal spindle morphology rate of oocytes pre-treated with Taxol prior to vitrification was not higher than that of other vitrified groups. Taxol pre-treatment did not increase cleavage and blastocyst formation rates, although control groups showed significantly higher rates (p<0.05). Percentages of normal spindle and embryonic development were not significantly different among vitrified groups regardless of type of sugar. In conclusion, Taxol pre-treatment of oocytes before cryopreservation did not reduce the damage induced by vitrification and subsequently did not improve embryonic development following vitrification. Trehalose may be used as an alternative non-permeating cryoprotectant in vitrification solution.

Dual-frequency Capacitively Coupled Plasma-enhanced Chemical Vapor Deposition System for Solar Cell Manufacturing

  • Gwon, Hyeong-Cheol;Won, Im-Hui;Sin, Hyeon-Guk;Rehman, Aman-Ur;Lee, Jae-Gu
    • Proceedings of the Korean Vacuum Society Conference
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    • 2011.08a
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    • pp.310-311
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    • 2011
  • Dual-frequency (DF) capacitively coupled plasmas (CCP) are used to separately control the mean ion energy and flux at the electrodes [1]. This separate control in capacitively coupled radio frequency discharges is one of the most important issues for various applications of plasma processing. For instance, in the Plasma Enhanced Chemical Vapor Deposition processes such as used for solar cell manufacturing, this separate control is most relevant. It principally allows to increase the ion flux for high deposition rates, while the mean ion energy is kept constant at low values to prevent highly energetic ion bombardment of the substrate to avoid unwanted damage of the surface structure. DF CCP can be analyzed in a fashion similar to single-frequency (SF) driven with effective parameters [2]. It means that DF CCP can be converted into SF CCP with effective parameters such as effective frequency and effective current density. In this study, comparison of DF CCP and its converted effective SF CCP is carried out through particle-in-cell/Monte Carlo (PIC-MCC) simulations. The PIC-MCC simulation shows that DF CCP and its converted effective SF CCP have almost the same plasma characteristics. In DF CCP, the negative resistance arises from the competition of the effective current and the effective frequency [2]. As the high-frequency current increases, the square of the effective frequency increases more than the effective current does. As a result, the effective voltage decreases with the effective current and it leads to an increase of the ion flux and a decrease of the mean ion energy. Because of that, the negative resistance regime can be called the preferable regime for solar cell manufacturing. In this preferable regime, comparison of DF (13.56+100 or 200 MHz) CCP and SF (60 MHz) CCP with the same effective current density is carried out. At the lower effective current density (or at the lower plasma density), the mean ion energy of SF CCP is lower than that of DF CCP. At the higher effective current density (or at the higher plasma density), however, the mean ion energy is lower than that of SF CCP. In this case, using DF CCP is better than SF CCP for solar cell manufacturing processes.

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Analysis for Water Vapour Adsorption and Desorption Performance of Waste Paper-Mulberry according to Particle Size Control (폐닥나무의 입도제어에 따른 흡·방습 특성 분석)

  • Jo, Ki-Sic;Kim, Tae-Yeon;Seo, Sung-Kwan;Lee, Oh-Kyu;Chu, Yong-Sik
    • Resources Recycling
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    • v.29 no.2
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    • pp.8-17
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    • 2020
  • In this study, adsorption and desorption characteristics of pulverized waste paper-mulberry pellet and bast fiber were measured to confirm the applicability to humidity control products. Paper-mulberry powder was classified by 710-355㎛, 355-100㎛, 100-45㎛ and less than 45㎛ and used in experiment. Specific surface area increased from 1.02㎡/g to 1.35㎡/g as the particle size decreased from 710㎛ to under 45㎛. Adsorption and desorption performance decreased in the order of 355-100㎛, 710-355㎛, 100-45㎛, less than 45㎛ and bast fiber, adsorption content on each particle sizes were 141.1g/㎡, 147.1g/㎡, 135.7g/㎡, 129.0g/㎡ and desorption content were 117.2g/㎡, 123.6g/㎡, 110.2g/㎡, 93.3g/㎡. As a result, adsorption and desorption performance of paper-mulberry powder were superior to those of the bast fiber and these phenomenon can be considered that it caused by pore distribution in pellet and damage of fiber.

A Comparative Study on the Effects of Pinellia ternata, Zingiber officinale and Sobanhatang on Reflux Esophagitis (역류성 식도염에 대한 반하(半夏), 생강(生薑), 소반하탕(小半夏湯)의 효과 비교)

  • Lee, Seul-hee;Baik, Tai-Hyeun
    • The Journal of Korean Medicine
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    • v.40 no.2
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    • pp.17-34
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    • 2019
  • Objectives: This study was carried out to observe and compare the effects of Pinellia ternata, Zingiber officinale and Sobanhatang on the reflux esophagitis induced by gastric fundus and pylorus ligation in mice with esomeprazole. Methods: Antioxidant effects were measured by DPPH radical scavenging activity at four different concentration of 0.125, 0.25, 0.5 and $1.0mg/102{\mu}{\ell}$. Zingiber officinale water extract(ZE), Pinellia ternata water extract(PE) and Sobanhatang water extract(SBE) and esomeprazole were treated orally for 14 days before gatric fundus and pylorus ligation. In the histochemistry, changes in suface mucous cells, muscle tissue and connective tissue in gastro esophageal junction(GEJ) and mast cell on the esophageal mucosa were observed. The change of Hemo oxygenase(HO)-1, ghrelin, gastrin and substance P in gastric body tissue were measured by immunohistochemistry. Results: DPPH radical scavenging activity exhibited concentration dependently increases in ZE, PE, SBE. ZE was significantly higher at all concentrations than PE. The gastric surface mucous cells were more in the treated group than in the reflux esophagitis elicited group(GE) in the order of PE, SBE, ZE and esomeprazole treateded group(PT, SBT, ZT, ET). Lower esophageal sphincter muscle damage and intercellular space in the GEJ were less in the treated group than GE. In the esophageal mucosa, the mast cell distribution and the migration of inflammatory cells were lower in the treateded troup than GE in order to ZT, SBT, PT and ET. The antioxidative enzyme, HO-1 was more in the order of ZT, SBT, control group, PT, ET than in GE. ZT was significantly higher than the other groups and SBT was significantly higher than ET. Ghrelin was found to be higher in ZT, ET, SBT and PT than in GE, and ZT was significantly higher than all other groups except ET. Gastrin showed the highest positivity in GE, and was lower in the order of ET, ZT, SBT, PT, and control group. Substance P was the highest in GE, and was lower in the order of ET, ZT, SBT, PT and control group, and PT were significantly lower than ET. Conclusion: ZT, PT and SBT showed superior antioxidative, anti-inflammatory and mucosal protective effects on mouse reflux esophagitis as compared with ET. In particular, ZE was more effective in antioxidant and gastric motility enhancement, while PE was more effective in mucosal protection and anti-inflammatory effects. Sobanhatang is expected to be effective treatment because it has advantages of both drugs and reduces toxicity.

On Vortex Reduction Characteristics of Pump Sump Circulating Water Intake Basin of Power Plant Using Hydraulic Experiment (수리실험을 이용한 발전소의 순환수 취수부 흡입수조의 와류저감에 관한 연구)

  • Eom, Junghyun;Lee, Du Han;Kim, Hung Soo
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.42 no.6
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    • pp.815-824
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    • 2022
  • Among the main facilities of the power plant, the circulating water used for cooling the power generation system is supplied through the Circulation Water Intake Basin (CWIB). The vortexes of various types generated in the Pump Sump (PS) of CWIB adversely affect the Circulation Water Pump (CWP) and pipelines. In particular, the free surface vortex accompanied by air intake brings about vibration, noise, cavitation etc. and these are the causes of degradation of CWP performance, damage to pipelines. Then power generation is interrupted by the causes. Therefore, it is necessary to investigate the hydraulic characteristics of CWIB through the hydraulic model experiment and apply an appropriate Anti Vortex Device (AVD) that can control the vortex to enable smooth operation of the power plant. In general, free surface vortex is controlled by Curtain Wall (CW) and the submerged vortex is by the anti vortex device of the curtain wall. The detailed specifications are described in the American National Standard for Pump Intake Design. In this study, the circulating water intake part of the Tripoli West 4×350 MW power plant in Libya was targeted, the actual operating conditions were applied, and the vortex reduction effect of the anti vortex device generated in the suction tank among the circulating water intake part was analyzed through a hydraulic model experiment. In addition, a floor splitter was basically applied to control the submerged vortex, and a new type of column curtain wall was additionally applied to control the vortex generated on the free surface to confirm the effect. As a result of analyzing the hydraulic characteristics by additionally applying the newly developed Column Curtain Wall (CCW) to the existing curtain wall, we have found that the vortex was controlled by forming a uniform flow. In addition, the vortex angle generated in the circulating water pump pipeline was 5° or less, which is the design standard of ANSI/HI 9.8, confirming the stability of the flow.

CHANGE OF TASTE PREFERENCE AND TASTE BUD AFTER UNILATERAL LINGUAL NERVE TRANSECTION IN RAT (백서 편측 설신경 손상 후 미각 및 설유두의 변화에 대한 연구)

  • Kim, Yoon-Tae;Jeon, Seung-Ho;Yeom, Hak-Ryol;Kang, Jin-Han;Ahn, Kang-Min;Kim, Sung-Min;Jahng, Jeong-Won;Park, Kyung-Pyo;Lee, Jong-Ho
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.31 no.6
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    • pp.515-525
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    • 2005
  • Purpose of study: Lingual nerve damage can be caused by surgery or trauma such as physical irriatation, radiation, chemotherapy, infection and viral infection. Once nerve damage occurred, patients sometimes complain taste change and loss of taste along with serious disturbance of tongue. The purpose of this study was to evaluate the effects of unilateral lingual nerve transection on taste as well as on the maintenance of taste buds. Materials & Methods: Male Sprague-Dawley rats weighing 220-250g received unilateral transection of lingual nerve, subjected to the preference test for various taste solutions (0.1M NaCl, 0.1M sucrose, 0.01M QHCl, or 0.01M HCl) with two bottle test paradigm at 2, 4, 6, or 8 weeks after the operation. Tongue was fixed with 8% paraformaldehyde. After fixation, they were observed with scanning electron microscope(JSM-$840A^{(R)}$, JEOL, JAPAN) and counted the number of the dorsal surface of the fungiform papilla for changes of fungiform papilla. And, Fungiform papilla were obtained from coronal sections of the anterior tongue(cryosection). After cryosection, immunostaining with $G{\alpha}gust$(I-20)(Santa Cruz Biotechnology, USA), $PLC{\beta}2$(Q-15)(Santa Cruz Biotechnology, USA), and $T_1R_1$(Alpha Diagnostic International, USA) were done. Immunofluorescence of labeled taste bud cells was examined by confocal microscopy(F92-$300^{(R)}$, Olympus, JAPAN). Results: The preference score for salty and sweet tended to be higher in the operated rats with statistical significance, compared to the sham rats. Fungiform papilla counting were decreased after lingual nerve transaction. In 2 weeks, maximum differences occurred. Gustducin and $T_1R_1$ expressions of taste receptor in 2 and 4 weeks were decreased. $PLC{\beta}2$ were not expressed in both experimental and control group. Conclusion: This study demonstrated that the taste recognition for sweet and salty taste changed by week 2 and 4 after unilateral lingual nerve transection. However, regeneration related taste was occurred in the presence of preserving mesoneurial tissue and the time was 6 weeks. Our results demonstrated that unilateral lingual nerve damage caused morphological and numerical change of fungiform papilla. It should be noted in our study that lingual nerve transection resulted in not only morphological and numerical change but also functional change of fungiform papillae.

Plasma Etching Characteristics of Sapphire Substrate using $BCl_3$-based Inductively Coupled Plasma ($BCl_3$ 계열 유도결합 플라즈마를 이용한 사파이어 기판의 식각 특성)

  • Kim, Dong-Pyo;Woo, Jong-Chang;Um, Doo-Seng;Yang, Xue;Kim, Chang-Il
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2008.11a
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    • pp.363-363
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    • 2008
  • The development of dry etching process for sapphire wafer with plasma has been key issues for the opto-electric devices. The challenges are increasing control and obtaining low plasma induced-damage because an unwanted scattering of radiation is caused by the spatial disorder of pattern and variation of surface roughness. The plasma-induced damages during plasma etching process can be classified as impurity contamination of residual etch products or bonding disruption in lattice due to charged particle bombardment. Therefor, fine pattern technology with low damaged etching process and high etch rate are urgently needed. Until now, there are a lot of reports on the etching of sapphire wafer with using $Cl_2$/Ar, $BCl_3$/Ar, HBr/Ar and so on [1]. However, the etch behavior of sapphire wafer have investigated with variation of only one parameter while other parameters are fixed. In this study, we investigated the effect of pressure and other parameters on the etch rate and the selectivity. We selected $BCl_3$ as an etch ant because $BCl_3$ plasmas are widely used in etching process of oxide materials. In plasma, the $BCl_3$ molecule can be dissociated into B radical, $B^+$ ion, Cl radical and $Cl^+$ ion. However, the $BCl_3$ molecule can be dissociated into B radical or $B^+$ ion easier than Cl radical or $Cl^+$ ion. First, we evaluated the etch behaviors of sapphire wafer in $BCl_3$/additive gases (Ar, $N_2,Cl_2$) gases. The behavior of etch rate of sapphire substrate was monitored as a function of additive gas ratio to $BCl_3$ based plasma, total flow rate, r.f. power, d.c. bias under different pressures of 5 mTorr, 10 mTorr, 20 mTorr and 30 mTorr. The etch rates of sapphire wafer, $SiO_2$ and PR were measured with using alpha step surface profiler. In order to understand the changes of radicals, volume density of Cl, B radical and BCl molecule were investigated with optical emission spectroscopy (OES). The chemical states of $Al_2O_3$ thin films were studied with energy dispersive X-ray (EDX) and depth profile anlysis of auger electron spectroscopy (AES). The enhancement of sapphire substrate can be explained by the reactive ion etching mechanism with the competition of the formation of volatile $AlCl_3$, $Al_2Cl_6$ or $BOCl_3$ and the sputter effect by energetic ions.

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