• Geomechanics and Engineering
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• v.25 no.1
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• pp.31-40
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• 2021

Injection grouting is one of the most common ground improvement practice to increase the strength and reduce the hydraulic conductivity of soils. Owing to the environmental concerns of conventional grout materials, such as cement-based or silicate-based materials, bio-inspired biogeotechnical approaches are considered to be new sustainable and environmentally friendly ground improvement methods. Biopolymers, which are excretory products from living organisms, have been shown to significantly reduce the hydraulic conductivity via pore-clogging and increase the strength of soils. To study the practical application of biopolymers for seepage and ground water control, in this study, we explored the injection capabilities of biopolymer-based grout materials in both linear aperture and particulate media (i.e., sand and glassbeads) considering different injection pressures, biopolymer concentrations, and flow channel geometries. The hydraulic conductivity control of a biopolymer-based grout material was evaluated after injection into sandy soil under confined boundary conditions. The results showed that the performance of xanthan gum injection was mainly affected by the injection pressure and pore geometry (e.g., porosity) inside the soil. Additionally, with an increase in the xanthan gum concentration, the injection efficiency diminished while the hydraulic conductivity reduction efficiency enhanced significantly. The results of this study provide the potential capabilities of injection grouting to be performed with biopolymer-based materials for field application.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.47 no.1
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• pp.1-5
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• 2010

In this paper, we directly compare the program efficiency of conventional channel hot electron (CHE) injection methods and a novel hot electron injection methods using substrate forward biases in our silicon-oxide-nitride-oxide-silicon (SONOS) cell. Compared with conventional CHE injection methods, the proposed injection method showed improved program efficiency including faster program operation at lower bias voltages as well as localized trapping features for multi-bit operation with a threshold voltage difference of 1 V at between the forward and reverse read. This program method is expected to be useful and widely applied for future nano-scale multi-bit SONOS memories.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.18 no.6
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• pp.76-81
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• 2019

In the mold-manufacturing field, various methods of advanced production technology are being used in the production of industrial-grade gear pulleys. Among the current methods are injection molding, hoop molding, insight molding, two-material molding, compound-mold molding, as well as engineering plastic mold. Currently, casting pulleys are inexpensive because they are produced in small quantities. However, they produce complications during the manufacturing process, are very unreasonable for mass production, and are disadvantageous in cost competitiveness. Pulleys are divided into hundreds of kinds and thousands of kinds, so the production methods vary. As these pulleys are made of a single material by a casting and welding method, they are not manufactured using injection molds consisting of different materials. In this research, pulleys, shafts, and reinforced plastic materials were incorporated using ANSYS software, and a low-cost, lightweight technology was applied for trial production with optimum design and extrusion technology.

• Journal of the Korea Institute of Building Construction
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• v.6 no.1 s.19
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• pp.87-91
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• 2006

Since water leakage and cracks are not the source of serious problems such as long-term lowering of performance and durability of a stricture, including damages to operating facilities of a structure, damages to internal finishing materials, exhibition, and goods, and pollution of residential environment, they might have led to development of positive coping skills; however, an instant loss of lives or property due to earthquake, explosion, typhoon, or a fire was indeed neglected. In these days, repair materials for leakage cannot help but being taken in temporary way without any noticeable countermeasure. This kind of repair is socially criticized many times that is defective construction even if this costs a lot. It was not arrange the standard for construction methods of sealer of injection type for leakage maintenance, even it has been used various type of construction methods for leakage part. In conclusion, we suggest that the construction methods of sealer of injection type for leakage maintenance for leakage to establish the leakage repairing technology as increase of structure demand. Therefore, it would be possible to provide a stage-by-stage solution by developing systematic research activities among the industry, schools, and research institutes to spread maintenance management techniques globally through technical solution to water leakage and cracks, acquisition of structural safety with prolonged durability for life cycle, reduction of water leakage repair expense s, and so on.

• Archives of Plastic Surgery
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• v.36 no.3
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• pp.269-276
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• 2009

Purpose: Local skin necrosis after extravasation of adriamycin, a widely used chemotherapeutic agent, is a common problem in cancer patients. The extravasation of chemotherapeutic agents yields severe inflammatory responses, crust formation, skin necrosis, and ulceration. Even though several treatment options have been proposed for extravasation injury, there is still controversy regarding the management of such lesions. Thus the aim of this study was to compare the efficacy of saline injection(Group 1), hydrocortisone injection(Group 2), propranolol injection(Group 3) and early surgical excision as a treatment(Group 4) in a rat extravasation model. Methods: The authors planned forty mature male Sprague - Dawley rats were divided into 4 groups and each group contained 10 rats. Administration of adriamycin($1.0mg/m{\ell}$) $1.5m{\ell}$ by subcutaneous injection on the dorsal side of the rats was followed by protocol. The treatment options were applied 2 hours after adriamycin injection. At the end of the 5th days, the presence and size of ulcers at the injection site were measured. 3 weeks after injection, a histopathologic examination was performed for each treatment and control group. T - tests were used to analyze the differences between the measurements. Results: Propranolol significantly improved tissue recovery compared with control group and other groups. These data suggest that there is little role for saline and hydrocortisone in the treatment of adriamycin extravasation injury. Conclusion: In this study, we compared some treatment methods in adriamycin extravasation model. The findings support the propranolol injection may prevent extravasation injury. However this study was performed in the laboratory using rats, and the results could be different in clinical application. Thus, more needs further investigations and clinical application.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.18 no.5
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• pp.135-148
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• 2008

The expansion of the internet has made web applications become a part of everyday lift. As a result the number of incidents which exploit web application vulnerabilities are increasing. A large percentage of these incidents are SQL Injection attacks which are a serious security threat to databases with potentially sensitive information. Therefore, much research has been done to detect and prevent these attacks and it resulted in a decline of SQL Injection attacks. However, there are still methods to bypass them and these methods are too complex to implement in real web applications. This paper proposes a simple and effective SQL Query attribute value removal method which uses Static and Dynamic Analysis and evaluates the efficiency through various experiments.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.5 no.2
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• pp.207-224
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• 1998

The purposes of this study were to identify nurse's recognition and performance and to represent the factors of hindrance in the IV therapy management. The subjects were 420 nurses who worked at five general hospitals in Pusan. Tha data were collected using a questionnaire and the period of data collection was from January 1 to January 31, 1998. The instrument for this study was made by author oneself on the basis of guidelines Simmons et al', CDC' Stanley' and Kurdi' guideline, Cllinical Nurse's Association' that consist of 68 items for 5 fields ; pre-injection, just before-injection, needle-injection, during injection, post-injection field. Cron-bach Alpha coefficient of recognition and performance in the IV therapy management was .93 and .87. The datas were analized by a SPSS program using frequency, percent, paired t-test, t-test and oneway ANOVA. The results obtained were as follows : 1. The mean score of recognition in IV therapy management was significantly higher than that of performance(t=5.86, P<.001). 2. The items of lower than mean score of each fields in performance were the identification of drugs, hands washing, patient teaching about medication, disinfectional methods of the injection site and the rubber stopper in bottle, the use of disposable gloves, mask and eye goggles at the chemotherapy preparation, use of tape and armboard, changing the IV tubing, labeling the dressing over the injection site, observation and recordings of patient's condition after medication and confirmation of the needle length at the needle removal. 3. The factors of hindrance in IV therapy were 'having no time', 'insufficiency of goods', 'unknowing of methods', 'no disadvantage', and 'factors of doctor's doing'. The most important factor was 'have no time', especially item of hands washing. The other factors of hindrance showed high frequency in the following items ; 'insufficiency of goods' in the use of disposable gloves, mask and eye goggles at the chemotherapy preparation, 'unknowing of methods' in the certification of drugs compatibility, 'no disadvantage' in the labeling the dressing over the injection site, and 'factors of doctor's doing' in the changing the subclavian catheter dressing and checking the glucose level during the TPN infusion. In conclusion, there is necessity of educational program which can improve the nurse's knowledge of drugs, disinfection methods, comfort of patient and recordings in IV therapy management and alternative plan which are political and financial aids such as setting up the sink, giving of paper towels and necessary goods in the IV therapy for reducing the factors of hindrance for IV therapy management.

• Transactions of Materials Processing
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• v.16 no.8
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• pp.596-602
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• 2007

LGP (Light Guiding Plate) of LCD-BLU (Liquid Crystal Display - Back Light Unit) is one of the major components that affect the product quality of LCD. The optical patterns of LGP(2.2") molds are fabricated by three different methods, namely, (1) laser ablation, (2) chemical etching and (3) LiGA-reflow, respectively. The characteristics of surface patterns and roughnesses of molds and injection molded parts were compared to evaluate the optical characteristics. The optical patterns of injection molded LGP with mold fabricated by LiGA - reflow method showed the best geometric structure. The surface roughness (Ra) of LGP#s with molds fabricated by (1) laser ablation: $Ra={\sim}31nm$, (2) chemical etching: $Ra={\sim}22nm$, and (3) LiGA-reflow: $Ra={\sim}4nm$.

• The Korean Journal of Pain
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• v.19 no.1
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• pp.51-55
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• 2006

Background: A cervical transforaminal steroid injection is an effective therapeutic modality for radiculopathy of a herniated cervical disc or a cervical foraminal stenosis. However, there is some debate regarding the safety of the transforaminal approach under C-arm guidance compared with the posterior interlaminar approach. We report a new technique for cervical transforaminal steroid injection guided by MDCT. Methods: Patients presenting with radiating pain on their shoulder or arm were diagnosed using CT or MRI of a cervical herniated disc or a foraminal stenosis. Each patient whose symptoms were compatible with the image scan was enrolled in this study. They received a cervical transforaminal steroid injection under CT guidance, and the effectiveness and complications of this technique were evaluated over a 2-month period. Results: According to the CT scan, none of the participants had an internal jugular vein or a carotid artery invasion during the procedure. No vertebral artery injection was noted, and no patient developed a hematoma after the injection. The VAS score had improved significantly by 2, 4 and 8 weeks after the injection. Conclusions: While a conventional C-arm guided cervical transforaminal steroid injection does not appear to differentiate between the major vessels and structures in images, a CT guided approach is a more useful and safer technique for the precise placement of a needle.

• Architectural research
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• v.11 no.2
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• pp.27-34
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• 2009

The purpose of this study is to investigate the problem of crack repair materials and methods in existing concrete structure and to propose the effective injection method on crack repair by packer type. The result of this study is as follows. It is investigated that the crack width in the inner matrix of concrete structure is decreased about 30-40% than that in the surface of the concrete structure. Also it is showed that the possibility which could be monolithic with injection part became higher if the injection part is installed near to surface of concrete on the punching method to vertical direction against crack area. The injection of repair material can be poured smoothly under about $10N/mm^2$ pressure on the condition that cracks are monolithic with injection part without dust by drill. The method which is effective injection for a repair material is the punching method in compliance with coredrill. But, the research continuously is necessary about minimum injection pressure.