• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.24 no.6
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• pp.462-469
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• 2014

After drilling operations at the offshore plant, crude oil is producted under high pressure. After that time, oil recovery is reduced, because the pressure of the pipe inside is low during the secondary produce. At that time injection sea water at the pipe inside through water injection pump that the device increase to recovery. A variety of mathematical analysis during the detailed design analysis was not made through the dynamics characteristic at the domestic company. 2D model has reliability of analysis results for the uncomplicated model. Also element and the node the number of significantly less than in the 3D model. So, the temporal part is very effective. In addition, depending on the quality of mesh 3D is a real model and FEM model occurs error. So, user needs a lot of skill. In this paper, a 2D finite element analysis was performed through the dynamics analysis and the study model was validated.

• Archives of Plastic Surgery
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• v.48 no.1
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• pp.133-143
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• 2021

Background Extensive research has been conducted on islet transplantation as a possible cure for diabetes. Islet transplantation in the liver via the portal vein has shown remarkable results, but numerous other recipient sites are currently being investigated. We aimed to show the effectiveness of using a muscle flap as a recipient site for islet transplantation. Methods Islet cells were harvested from 12 isogenic Lewis rats, and then diabetes was induced in another 12 isogenic Lewis rats by streptozotocin injection. In six rats, 3,000 islets were transplanted into gastrocnemius muscle flaps, and in the other six rats, the same number of islets were transplanted into the gastrocnemius muscle. The transplanted islet cell function between the two groups was compared by means of blood glucose tests, glucose tolerance tests, immunohistochemistry, and real-time reverse transcription polymerase chain reaction. Results In the muscle flap group, blood glucose levels significantly decreased after islet transplantation. Blood glucose levels were significantly different between the two groups at 3 weeks after transplantation. The muscle flap group showed nearly normoglycemic results upon the glucose tolerance test, whereas the muscle group was hyperglycemic. Immunohistochemical evaluation showed positive results against insulin and glucagon in biopsies of both groups, and the islet cell density was higher in the muscle flap group. There were no statistically significant differences between the two groups in real-time reverse transcription polymerase chain reaction results. Conclusions Our results suggest that muscle flaps are promising candidates for islet cell transplantation.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.41 no.6
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• pp.397-407
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• 2017

In this study, a SCR system is employed to selectively reduce $NO_X$, which is a major cause of environmental pollution and issues in diesel engines. In particular, this paper focuses on the combination of feedforward injection strategies, depending on the NO/$NO_X$ ratio, and feedback injection control, using $NH_3$ coverage ratio, based on a SCR model. A 2.2 L passenger diesel engine, which is equipped with a diesel oxidation catalyst (DOC) and a diesel particle filter (DPF), was used in the experiments. The developed control algorithm is implemented on a real-time computer with injection control algorithm. By analyzing the $NO_X$ emission measurement, the performance of the proposed injection control algorithm is verified.

• Development and Reproduction
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• v.24 no.1
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• pp.43-52
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• 2020

NUCB2/nesfatin-1 known to regulate appetite and energy homeostasis is expressed not only in the hypothalamus, but also in various organs and tissues. Our previous reports also demonstrated that NUCB2/nesfatin-1 was expressed in the reproductive organs, including the ovaries, uterus, and testes of mice. However, it is yet known whether NUCB2/nesfatin-1 is expressed in the oviduct and how its expression is regulated. Therefore, we investigated the expression of NUCB2/nesfatin-1 in the oviduct and its expression is regulated by gonadotropin. Immunohistochemical staining results showed that nesfatin-1 protein was localized in epithelial cells of the oviduct. As a result of quantitative real-time PCR (qRT-PCR) and Western blot, NUCB2/nesfatin-1 was detected strongly in the oviducts. During the estrus cycle, NUCB2/nesfatin-1 expression in the oviducts was markedly higher in the proestrus stage than in other estrus stages. In order to elucidate whether the expression of NUCB2 mRNA is controlled by the gonadotropins, we injected PMSG and hCG and measured NUCB2 mRNA level in the oviduct after injection. Its level was increased in the oviduct after PMSG injection, but no significant change after hCG injection. In addition, NUCB2 mRNA levels were markedly reduced after ovariectomy, while recovered after 17β-estradiol (E2) injection, but not by progesterone (P4). This study demonstrated that NUCB2/nesfatin-1 is highly expressed in the oviduct of mouse and its expression is regulated by E2 secreted by the ovaries. These results suggest that NUCB2/nesfatin-1 expressed by the oviduct may affect the function of the oviduct regulated by the ovaries.

• The Korean Journal of Pain
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• v.22 no.1
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• pp.52-57
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• 2009

Background: Transforaminal epidural injection (TEI) may be useful to treat unilateral pain that has a dermatomal distribution. In this approach, the needle tip can be placed closer to the dorsal root ganglion and ventral aspect of the nerve root. However many studies have reported that serious complications following TEI occurred more frequently when it was conducted at the cervical level. One of the presumptive mechanisms of the complication is intravascular injection. Therefore this study was conducted to identify the incidence of complications in response to intravascular injections at cervical segments. Methods: This study included all patients, who visited our pain clinic and had radicular symptoms or herpes zoster associated pain. All procedures were conducted under fluoroscopic guidance with contrast enhancement by one of the authors. After the ideal needle position was confirmed by biplanar fluoroscopy, the blood aspiration through the needle hub was evaluated, and a 3 ml mixture of nonionic contrast (2 ml) with normal saline (1 ml) was injected at a rate of 0.3-0.5 ml/sec continuously under real time fluoroscopic visualization. We then classified the contrast spreading pattern as neural, simultaneous neural and vascular, or vascular. Results: A total 71 cervical TEIs were performed. In 26 cases (36.6%), the contrast only spread to the nerve sheath. However, 45 cases (63.4%) showed an intravascular spreading pattern, 37 (52.1%) of which showed a neural and vascular pattern and 8 (11.3%) of which showed only a vascular pattern. Conclusions: Approximately two thirds of the cases of cervical TEI were found to lead to intravascular spreading, which is much higher than the incidence reported in previous studies.

• Journal of IKEEE
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• v.26 no.3
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• pp.380-388
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• 2022

The traditional malware detection technologies collect known malicious programs and analyze their characteristics. Then such a detection technology makes a blacklist based on the analyzed malicious characteristics and checks programs in the user's system based on the blacklist to determine whether each program is malware. However, such an approach can detect known malicious programs, but responding to unknown or variant malware is challenging. In addition, since such detection technologies generally monitor all programs in the system in real-time, there is a disadvantage that they can degrade the system performance. In order to solve such problems, various methods have been proposed to analyze major behaviors of malicious programs and to respond to them. The main characteristic of ransomware is to access and encrypt the user's file. So, a new approach is to produce the whitelist of programs installed in the user's system and allow the only programs listed on the whitelist to access the user's files. However, although it applies such an approach, attackers can still perform malicious behavior by performing a DLL(Dynamic-Link Library) injection attack on a regular program registered on the whitelist. This paper proposes a method to respond effectively to attacks using DLL injection.

• Clinical Pain
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• v.18 no.2
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• pp.59-64
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• 2019

Objective: This study evaluated the feasibility of ultrasound-guided lumbar nerve root block (LNRB) and S1 nerve root block by identifying spread patterns via fluoroscopy in cadavers. Method: A total of 48 ultrasound-guided injections were performed in 4 fresh cadavers from L1 to S1 roots. The target point of LNRB was the midpoint between the lower border of the transverse process and the facet joint at each level. The target point of S1 nerve root block was the S1 foramen, which can be visualized between the median sacral crest and the posterior superior iliac spine, below the L5-S1 facet joint. The injection was performed via an in-plane approach under real-time axial view ultrasound guidance. Fluoroscopic validation was performed after the injection of 2 cc of contrast agent. Results: The needle placements were correct in all injections. Fluoroscopy confirmed an intra-foraminal contrast spreading pattern following 41 of the 48 injections (85.4%). The other 7 injections (14.6%) yielded typical neurograms, but also resulted in extra-foraminal patterns that occurred evenly in each nerve root, including S1. Conclusion: Ultrasound-guided injection may be an option for the delivery of injectate into the S1 nerve root, as well as lumbar nerve root area.

• Journal of Microbiology and Biotechnology
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• v.21 no.1
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• pp.81-88
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• 2011

The anti-phytoplasma activities of surfactin (derived from Iranian native Bacillus subtilis isolates) and tetracycline towards Candidatus "Phytoplasma aurantifolia", the agent of lime Witches' broom disease, were investigated. HPLC was used to quantify the surfactin production in four previously characterized native surfactin-producing strains, and the one producing the highest amount of surfactin (about 1,500 mg/l) was selected and cultivated following optimized production and extraction protocols. Different combinations of purified surfactin and commercial tetracycline were injected into artificially phytoplasmainfected Mexican lime seedlings using a syringe injection system. An absolute quantitative real-time PCR system was developed to monitor the phytoplasma population shifts in the lime phloem during 3 months following the injections. The results revealed that the injections of surfactin or tetracycline had a significant inhibitory effect on Candidatus "P. aurantifolia". However, the combined treatment with both surfactin and tetracycline (1:1) resulted in the highest inhibition due to a synergic effect, which suppressed the phytoplasma population from about $2{\times}10^5$ to less than 10 phytoplasma units/g plant tissue.

• 한국연소학회:학술대회논문집
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• 2003.05a
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• pp.75-83
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• 2003

Diode laser absorption system is advantageous of their non-invasive nature, fast response time, high sensitivity and real-time measurement capability. Furthermore, recent advances in room-temperature, near-IR and visible diode laser sources for telecommunication, optical data storage applications are enabling combustion diagnostics system based on diode laser absorption spectroscopy. So, combined with fiber-optics and high sensitive detection strategies, compact and portable sensor system are now appearing for a variety of applications. The objective of this research is to take advantage of distributed feed-back diode laser and develope new gas sensing system. It experimentally found out that the wavelength, power characteristics as a function of injection current and temperature. In addition to direct absorption and wavelength modulation spectroscopy have been demonstrated in these experiments and have a bright prospect to this diode laser system.

• Journal of Korean Society of Water and Wastewater
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• v.12 no.2
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• pp.76-82
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• 1998

It is necessary to calculate the accurate velocity from the hydraulic model for the reliable prediction of water quality changes in water supply system. To verify the hydraulic analysis of the water supply system, fluoride was used as a tracer to calculate the travel time from the injection point to the sampling points. Results from this field experiment indicate that fluoride can be a good conservative tracer while it showed a little longitudinal dispersion along the pipe lines. And the velocity from the model was verified by these travel times and calibrated by changing the ratio of the unaccountable water. When the ratio of the unaccountable water. When the ratio of the unaccountable water was 20%, the error between the estimation of hydraulic model and the real travel time was minimum.