• Journal of the Korea institute for structural maintenance and inspection
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• v.12 no.5
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• pp.133-142
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• 2008

This paper studies the early-aged chloride binding capacity of various blended concretes including OPC(ordinary Portland cement), PFA(pulversied fly ash), GGBFS(ground granulated blast furnace slag) and SF(silica fume) cement paste. Cement pastes with 0.4 of a free water/binder ratio were cast with chloride admixed in mixing water, which ranged from 0.1 to 3.0% by weight of cement and different replacement ratios for the PFA, GGBFS and SF were used. The content of chloride in each paste was measured using water extraction method after 7 days curing. It was found that the chloride binding capacity strongly depends on binder type, replacement ratio and total chloride content. An increase in total chloride results in a decrease in the chloride binding, because of the restriction of the binding capacity of cement matrix. For the pastes containing maximum level of PFA(30%) and GGBFS(60%) replacement in this study, the chloride binding capacity was lower than those of OPC paste, and an increase in SF resulted in decreased chloride binding, which are ascribed to a latent hydration of pozzolanic materials and a fall in the pH of the pore solution, respectively. The chloride binding capacity at 7 days shows that the order of the resistance to chloride-induced corrosion is 30%PFA > 10%SF > 60%GGBFS > OPC, when chlorides are internally intruded in concrete. In addition, it is found that the binding behaviour of all binders are well described by both the Langmuir and Freundlich isotherms.

• Archives of Reconstructive Microsurgery
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• v.18 no.2
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• pp.55-61
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• 2009

Purpose: To analyze the clinical and radiologic results of the shoulder arthrodesis in brachial plexus injury patients with flail upper extremity. Material and Method: From Aug 1978 to April 2008, 29 shoulders in 29 patients with brachial plexus injury with shoulder fusion, we evaluated 20 shoulders in 20 patients, more than 1 year follow up. The average follow-up period was 6.45years (range: 1year~24years). There were 13 men and 7 women, and the mean age at the time of trauma was 32.0years(2~65 years). The type of injury was a motorcycle accident in 11 patients, in car accident in 5, pedestrian accident in 3, and fall from a height in 1. The lesion of injury was root and trunk in 1 patient, trunk and cord in 1, trunk in 18. Surgery was performed on the whole arm type paralysis in 12 patients, lower arm type paralysis in 8 patients. The preoperative visual analog scale score was 8.7(7~10). When the trapezius and serratus anterior muscle were in function, operation was performed. 18 patients were processed to the additional operation. Gracilis free flap in 6 patients, neurotization in 3, Steindler flexor plasty in 6, and tendon transfer in 3 were performed. Fixation was conducted with cancellous screws in 13 patients, Knoles pins in 5, and cancellous screws and Knoles pins in 2. The position of the arthrodesis at operation was $28.5^{\circ}$($20~45^{\circ}$) in abduction, $30.3^{\circ}$($20~45^{\circ}$) in flexion, and $30.8^{\circ}$($20~40^{\circ}$) in internal rotation. Result: The follow up visual analog scale score was 3.4(0~7). Postoperatively, shoulder spica cast was applied for 15.3weeks(8-20weeks). The median time to bony union was 17.7weeks(9~28weeks). Average range of motion was $32.0^{\circ}$($15~40^{\circ}$) of abduction, $24.0^{\circ}$($10~40^{\circ}$) of flexion, and $18.5^{\circ}$($10~30^{\circ}$)of internal rotation. Conclusion: The shoulder fusion in brachial plexus injury patients is one of the good methods to relieve pain, improve the function and stabilize the flail shoulder joint.

• The Korean Journal of Pain
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• v.6 no.2
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• pp.275-279
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• 1993

Reflex sympathetic dystrophy is a syndrome characterized by persistent, burning pain, hyperpathia, allodynia & hyperaesthesia in an extremity, with concurrent evidence of autonomic nervous system dysfunction. It generally develops after nerve injury, trauma, surgery, et al. The most successful therapies are directed towards blocking the sympathetic intervention to the affected extremity by regional sympathetic ganglion block or Bier block with sympathetic blocker; other traditional treatments include transcutaneous electrical stimulation, immobilization with cast & splint, physical therapy, psychotherapy, administration of sympathetic blocker, calcitonin, corticosteroid and analgesic agents. The purpose of this report is to evaluate and describe the effects of magnetic resonance following unsatisfactory results with traditional treatments of RSD. A 17 year old female patient, 1 year earlier, had received excision and drainage of pus at the right femoral triangle due to an injury caused by a stone. Afterwards, she experienced burning pain, knee joint stiffness, and muscle dystrophy of the right thigh, especially when standing and walking. Despite a year of number of traditional treatments such as: lumbar sympathetic block, continuous epidural analgesia, transcutaneous electrical stimulation, & administration of predisolone, her pain did not improve. Surprisingly, the patients was able to walk free from pain and difficulty after just one application of magnetic resonance. The patient has been successfully treated with further treatment of two to three times a week for approximately ten weeks. More recently, magnetic resonance has been demonstrated to produce effective results for the relief of pain in a variety of diseases. From our experiences we recognize magnetic resonance as a therapeutic modality which can provide excellent results for the treatment of RSD. It has been suggested that polysynaptic reflex which are disturbed in RSD may be modulated normally on the spinal cord level through the application of magnetic resonance.

• Journal of Periodontal and Implant Science
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• v.35 no.2
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• pp.359-369
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• 2005

It has been suggested that morphologic characteristics of the periodontium are partly related to the shape and form of the teeth. Furthermore, the severity of symptoms of periodontal disease have been proposed to differ among these various morphologic entities or "biotypes". The purpose of the present study was to examine the relationship between the form of the crowns in the maxillary anterior tooth segment and (1) a group of morphological characteristics and (2) the thickness of the gingiva. The thickness of gingiva was measured by ultrasonic device(SDM). 100 subjects devoid of symptoms of destructive periodontal disease were examined regarding, e.g., probing depth, gingival recession, width of keratinized gingiva, thickness of the keratinized gingiva. From maxillary study cast, the width(at the apical third-CW) and the length(CL) of the crowns of the 6 anterior teeth were determined. A CW/CL-ratio was calculated for each tooth and averaged for each tooth region. The individual mean CW/CL-ratio values for the central incisors were ranked. The 10 subjects ranked highest and the 10 ranked lowest were selected as having either a long-narrow(group N) or a short-wide(group W) form of the crown of the tooth. The data for each of the examined parameters were averaged for each tooth region in each subject and mean values for subjects in groups W and N were compared using the Student t-test. Stepwise multiple regression analysis, including data from the whole sample, was performed for each tooth region with the thickness of the free gingiva as the dependent variable. The results from the analyses demonstrated that individuals with a long-narrow form of the central incisors displayed, compared to individuals with a short-wide crown, form (l) a narrow zone of keratinized gingiva, (2) a pronounced "scalloped" contour of the gingival margin. There was no significant difference between groups N and W with respect to the thickness of the keratinized gingiva. The CW/CL-ratio data revealed that a certain form of the crowns in the central incisors was accompanied by a similar form in the lateral incisors and canine tooth region. The regression analyses demonstrated that the thickness of the keratinized gingiva in central, lateral incisors and canines was significantly related to the width of the keratinized gingiva.

• Journal of the Korea Concrete Institute
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• v.21 no.3
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• pp.245-253
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• 2009

The importance of chloride ions in the corrosion of steel in concrete has led to the concept for chloride threshold level (CTL). The CTL can be defined as the content of chlorides at the steel depth that is necessary to sustain local passive film breakdown and hence initiate the corrosion process. Despite the importance of the CTL, due to the uncertainty determining the actual limits in various environments for chloride-induced corrosion, conservative values such as 0.4% by weight of cement or 1.2 kg in 1 $m^3$ concrete have been used in predicting the corrosion-free service life of reinforced concrete structures. The paper studies the CTL for blended cement concrete by comparing the resistance of cementitious binder to the onset of chloride-induced corrosion of steel. Mortar specimens were cast with centrally located steel rebar of 10 mm in diameter using cementitious mortars with ordinary Portland cement (OPC) and mixed mortars replaced with 30% pulverized fuel ash (PFA), 60% ground granulated blast furnace slag (GGBS) and 10% silica fume (SF), respectively, at 0.4 of a free W/B ratio. Chlorides were admixed in mixing water ranging 0.0, 0.2, 0.4, 0.6, 0.8, 1.0, 1.5, 2.0, 2.5 and 3.0% by weight of binder(Based on $C1^-$). Specimens were curd 28 days at the room temperature, wrapped in polyethylene film to avoid leaching out of chloride and hydroxyl ions. Then the corrosion rate was measured using the polarization resistance method and the order of CTL for binder was determined. Thus, CTL of OPC, 60%GGBS, 30%PFA and 10%SF were determined by 1.6%, 0.45%, 0.8% and 2.15%, respectively.

• Journal of Korean Philosophical Society
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• v.137
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• pp.57-79
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• 2016

The purpose of this paper is to explain MacIntyre's critique of moral pluralism of modern society and reveal the limits of his critique of liberalism. It is a distinctive feature of the social and cultural order that we inhabit that disagreements over central moral issues are peculiarly unsettleable. Debates concerned with the value of human life such as those over abortion and euthanasia, or about distributive justice and property rights, or about war and peace degenerate into confrontations of assertion and counter-assertion because the protagonists of rival positions invoke incommensurable forms of moral assertion against each other. We usually call this situation 'modern moral pluralism' and concede as the natural outcome of the activities of human reason under free institution. But in After Virtue, MacIntyre vigorously criticizes modern moral pluralism. The main cause he took which brought about this state of affairs was the failure of 'the Enlightenment project'. According to MacIntyre, the Enlightenment project which has dominated philosophy for the past three hundred years promised a conception of rationality independent of historical and social context, and independent of any specific understanding of man's nature or purpose. But not only has that promise in fact been unfulfilled, the project is itself fundamentally flawed and the promise could never be fulfilled. In consequence, modern moral and political thought are in a state of disarray from which they can be rescued only if we revert to an Aristotelian paradigm, with its essential commitment, and construct an account of practical reason premised on that commitment. But one of the deepest difficulties with the argument of After Virtue is that the very extent of its critique of the modern world seems to cast doubt on the possibility of any realistic revival under the conditions of modernity of the Aristotelianism which MacIntyre advocates. Especially when we consider we are not only the characters found in our narratives but also we ourselves are the author of our own narratives. Moral pluralism is not seen as disaster but rather as the natural outcome of the activities of human reason under enduring free institutions.

• Korea Science and Art Forum
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• v.37 no.4
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• pp.149-159
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• 2019

This research was started to identify the color status of signboards at the target site and suggest the direction of improvement for the signboard project in Dongsang-dong, Jongno-gil, a central area of the old city center of Gimhae. The area under study forms a depressed street atmosphere with old facilities, and is a typical type of old city center sign that needs to be rebuilt. The purpose of this study is to investigate prior research related to signage and similar signboard improvement cases, and then to identify the current status of colors by sorting out the casting, auxiliary and highlighted colors through the survey of the color of the signboard in the target area, and to propose a desirable direction for the future sign business based on the basis of these findings. This paper divided the target sections by industry and conducted a color analysis of signboards. The results and contents of the research are as follows. First, cast-colored signboards in general businesses showed a variety of primary color distributions with high L* values, on average, with high intensity and high chromaticity. Second, the auxiliary colors were mostly white or black in color-free, making a contrast between the casting colors. Third, the highlight was that a* value showed a high distribution in positive water plus and was mainly distributed in obsolescence, such as red or yellow, and color was used to reflect the characteristics of each store. However, the stores in the entire section lack unity because they were using colors that were higher in color than middle colors, which was causing the street's aesthetic look to be undermined. Based on the results of these studies, it is thought that the future color scheme for Gimhae's signature improvement project will limit the number of colors to a certain extent and give a sense of security and visual comfort to the use of colorlessness and obscurity around the representative colors of Gimhae.