• Journal of the Korea Institute of Information Security & Cryptology
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• v.13 no.1
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• pp.147-155
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• 2003

The diffusion of internet infrastructure and a fast increase of Population to use it is becoming a base of the service that can use various information, data and digital contents which were provided through off-line physically and used. Recently, the. techniques for copy deterrence and copyright protection have been important in e-commerce because various contents in digital form can be duplicated easily. The Access Control(AC) technique that only a user having the qualifications can access and use contents normally has been studied. The Conditional Access System(CAS) used in a satellite broadcasting md Digital Right Management System(DRMS) used for contents service are representative models of current commercialized access control. The CAS and DRM can be considered as an access control technique based on the payment based type(PBT). This paper describe the access control method of payment free type(PFT) suggested in ［5］ which are independent on the payment structure. And then we suggest a new access control method of payment free type which is more efficient than the previous one.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.3A
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• pp.407-415
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• 2008

Hydration reaction of Free-CaO is thought to be the main reason of expansion failure of slag. A lot of research institutions are conducting studies on solutions to this problem, and moreover it has been carried out how to make use of aggregates for concrete. While studies covering wide rage of blast furnace slag have been accomplished in the country, studies on steelmaking slag are insufficient. Therefore, this study aimed at analyzing basic physical properties of electric arc furnace oxidizing slag, which is the main material, and furthermore it focused on how to make use of aggregates for concrete examining chemical mechanism, which can be put to practical use. To address this issue, components of electric arc furnace oxidizing slag were analyzed with measurement of physical properties, followed by long-term strength and detailed durability analysis, which can evaluate the appropriateness of application of cement concrete. Besides the environmental conservation and recycling which can be obtained by application of industry byproducts, commercializing of electric arc furnace oxidizing slag as fine aggregates for cement concrete are expected.

• The Journal of the Korea institute of electronic communication sciences
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• v.9 no.1
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• pp.111-122
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• 2014

This paper proposes a new strategy for assisting SMEs in S. Korea to grow by the use of free technologies, which include expired patents, patents that are effective in other countries but not in S. Korea, and technologies that were published without being patented. A key question answered in this paper is how to find valuable technologies developed by large companies that can be utilized by domestic SMEs. A procedure for identifying emerging free technologies was developed and is explained with an example. A quantitative analysis of technology trend was conducted on PCT's published patents that did not include S. Korea as a designated country, and then emerging IPC subclasses were identified. Among those emerging technology areas, the subclass areas where the number of Korean inventors is small were identified as key emerging free technology areas. Our method for identifying emerging free technologies can assist domestic SMEs to advance in the international market and guide the development of a national industrial strategy.

• Journal of The Korean Association For Science Education
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• v.22 no.1
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• pp.122-131
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• 2002

Recently, performance assessment that makes growing use of free response items in a large scale assessment has been emphasized. This study is an empirical examination of the effectiveness of free response items in comparison with multiple choice items. Using the information function in Item Response Theory (IRT) framework, item information of free response items and multiple-choice items from the Third International Mathematics and Science Study-Repeat (TlMSS-R) were obtained. Test information of the whole science area as well as each area of science contents was computed. On average, free response items yielded more information than multiple choice items, especially in earth science, physics, chemistry, and life science. This study also showed that free response items were appropriate for students in high science ability. Also, free response items estimated students' science ability more accurately than multiple choice items with smaller number of free response items.

• Journal of The Korean Digital Architecture Interior Association
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• v.11 no.2
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• pp.13-19
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• 2011

Starting in modern times by Le Corbusier, architectures made by concretes are still developing in these times. For several decades, the shape of box architecture has been the most familiar type of buildings. Of course "The concrete is the type of box building" isn't always right, but what we have most seen was the buildings which has been stylized and made by concretes. Through modern times to these days based on international style and functionalism, the type of box building was the most effective and good profit type of architecture which has not disregarded the capitalism. Free-form building are becoming a common place, and many of these are designed and constructed using sophisticated techniques. The main technique being used is Generative Technology of Form for free-form construction. People's interest is growing in this, and it is becoming widely used both abroad and domestically. The purpose of this paper is to investigate the use of Generative Technology of Form which is a digitally adapted design methodology in architecture. The digital design process used for contemporary buildings share many typical features that exist within a standard digital template, but also an increasing amount of mass customization that has to be produced at an additional cost. This paper will summarize these features in terms of free-form architecture, and in terms of the digital design process. In fact, 3D models have to be conceded as main design products considering features of Free Form Design Architecture. However it is practical to design twice over, because all forms of architectural drawings are 2D. From now on, design of Free Form Design Building is not to separate between design process and practical process, but to compound them as unified design system applied the process to communicate information interactively. For this, it should be required to impose unified digital design process and perform researches about effective way to apply in the field of Free-form Design Architecture.

• Archives of Plastic Surgery
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• v.40 no.4
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• pp.353-358
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• 2013

Background Robots have allowed head and neck surgeons to extirpate oropharyngeal tumors safely without the need for lip-split incision or mandibulotomy. Using robots in oropharyngeal reconstruction is new but essential for oropharyngeal defects that result from robotic tumor excision. We report our experience with robotic free-flap reconstruction of head and neck defects to exemplify the necessity for robotic reconstruction. Methods We investigated head and neck cancer patients who underwent ablation surgery and free-flap reconstruction by robot. Between July 1, 2011 and March 31, 2012, 5 cases were performed and patient demographics, location of tumor, pathologic stage, reconstruction methods, flap size, recipient vessel, necessary pedicle length, and operation time were investigated. Results Among five free-flap reconstructions, four were radial forearm free flaps and one was an anterolateral thigh free-flap. Four flaps used the superior thyroid artery and one flap used a facial artery as the recipient vessel. The average pedicle length was 8.8 cm. Flap insetting and microanastomosis were achieved using a specially manufactured robotic instrument. The total operation time was 1,041.0 minutes (range, 814 to 1,132 minutes), and complications including flap necrosis, hematoma, and wound dehiscence did not occur. Conclusions This study demonstrates the clinically applicable use of robots in oropharyngeal reconstruction, especially using a free flap. A robot can assist the operator in insetting the flap at a deep portion of the oropharynx without the need to perform a traditional mandibulotomy. Robot-assisted reconstruction may substitute for existing surgical methods and is accepted as the most up-to-date method.

• Archives of Plastic Surgery
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• v.42 no.6
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• pp.729-734
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• 2015

Background Insufficient satisfaction outcome literature exists to assist consultations for scar revision surgery; such outcomes should reflect the patient's perspective. The aim of this study was to prospectively investigate scar revision patient satisfaction outcomes, according to specified patient-selection criteria. Methods Patients (250) were randomly selected for telephone contacting regarding scar revisions undertaken between 2007-2011. Visual analogue scores were obtained for scars pre- and post-revision surgery. Surgery selection criteria were; 'presence' of sufficient time for scar maturation prior to revision, technical issues during or wound complications from the initial procedure that contributed to poor scarring, and 'absence' of site-specific or patient factors that negatively influence outcomes. Patient demographics, scar pathogenesis (elective vs. trauma), underlying issue (functional/symptomatic vs. cosmetic) and revision surgery details were also collected with the added use of a real-time, hospital database. Results Telephone contacting was achieved for 211 patients (214 scar revisions). Satisfaction outcomes were '2% worse, 16% no change, and 82% better'; a distribution maintained between body sites and despite whether surgery was functional/symptomatic vs. cosmetic. Better outcomes were reported by patients who sustained traumatic scars vs. those who sustained scars by elective procedures (91.80% vs. 77.78%, P=0.016) and by females vs. males (85.52% vs. 75.36%, P<0.05), particularly in the elective group where males (36.17%) were more likely to report no change or worse outcomes versus females (16.04%) (P<0.01). Conclusions Successful scar revision outcomes may be achieved using careful patient selection. This study provides useful information for referring general practitioners, and patient-surgeon consultations, when planning scar revision.

• Archives of Plastic Surgery
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• v.36 no.6
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• pp.707-713
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• 2009

Purpose: The deep inferior epigastric perforator(DIEP) free flap is well known as an ideal donor site for the breast reconstruction. The flap can provide huge amount of fat tissue for breast and buttock contour, while it is also very useful as a thin skin flap to reconstruct the upper and lower extremities. We used a DIEP free flap in various site reconstructions besides the breast and would like to reinsure the usefulness of this flap. Methods: Twenty nine consecutive patients who underwent DIEP free flap surgery from 2001 January to 2007 December were reviewed. The case constituted seven male patients and twenty two female patients. There were sixteen breast reconstructions, five face reconstructions, five lower extremity reconstructions, two upper extremity reconstructions, and one buttock contour reconstruction. All clinical data were based on the patient's medical records. Results: All DIEP free flaps survived without major complications. There was no hematoma, seroma, or partial necrosis. The donor sites were closed primarily with linear scar on lower abdomen. The thinnest part of flap was 0.7 cm in thickness. The size of the largest flap was $38{\times}13cm$. The flaps were used in various types of skin and adipose tissue, adipose tissue only, and skin only according to the requirement of recipient site. Conclusion: The DIEP free flap was enough to provide a thin and huge flap for both breast and extremity reconstructions. It was able to provide versatile designs with sufficient adipose tissue. So we use it for 3 - dimentional face and buttock contour reconstructions. The DIEP free flap is a valuable reconstructive donor for face, upper and lower extremity in addition to breast without compromising the integrity of abdominal wall.

• Korean Journal of Microbiology
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• v.5 no.2
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• pp.79-85
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• 1967

Kim, Jong Hyup., (Div. of Biology, Atomic Energy Research Institute,Korea.;) Studies on the Cellulor Metabolism in Microorganisms as influenced by Gamma-irradiation(III): On the Changes of Free Amino acid Pool and content of Protein in Yeast clls irradiated by .gamma.-ray. 1. The strain of Saccharomyces cerevisiae had been cultured synchronously in aerobic condition and irradiatel by gamma-ray from the source of cobalt-60. Drying in vacuum oven at $90^{\circ}C$ C over 12 hours, then changes of protein content (Kjeldahl) and free amino acid pool have been assayed with use of spectrophotometer. Results obtained were compared with those of unirradiated normal cells. 2. It is proved that amount of protein content in the irradiated cells increases to seven percent more than those of normal cells in the same weight of dried samples. It seems like carbohydrate breakown had been stimulated by irradiation and that relative contents of protein shows higher values than those of normal in the same weight of samples. 3. The amount of free amino acid pool in the irradiated cells shows less value about ten percent than those of normal cells, and rate of decreasing is also weak than those of standard reagent solution of amino acid. We may assume that free amino acid pool would be protected against radiation damage in living cells and more stable than in vitro. 4. The component of free amino acid pool have been assayed on second dimensional paper chromatogram, and the identified amino acids are as follows; aspartic acid, serine, glutamic acid, cystine, lysine, glycine, threonine, histidine, arginine, tyrosine, phenylalanine, valine and leucine. 5. Distributional presence of free amino acids are identical to that of normal cells except arginine, it is cosumable that radiation effect is univerlsal to all amino acid. However it is obvious that there are differences in radiolabilities of amino acids in irradiated cells.

• Archives of Plastic Surgery
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• v.45 no.5
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• pp.466-469
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• 2018

The highly contoured nature of the nose and the abundant free margin makes it especially difficult to reconstruct. In this report, we describe the use of a new helical rim free flap technique for the reconstruction of full-thickness nasal alar defects via supermicrosurgery. Briefly, after a wide excision with a margin of 0.7 cm, an alar defect with a size of $1{\times}1{\times}0.5cm$ was obtained, which included the full thickness of the skin, mucosa, and lower lateral cartilage. Vessel dissection was performed in a straightforward manner, starting from the incision margin for flap harvest, without any further dissection for reach the greater trunk of the superficial temporal artery. The flap was inset in order to match the contour of the contralateral ala. We closed the donor site via rotation and advancement. No donor site morbidity was observed, despite the presence of a small scar that could easily be covered with hair. The alar contour was satisfactory, and the patient was satisfied with the results. The supermicrosurgical technique did not require further dissection to identify the vessels for anastomosis, leading to better cosmetic outcomes and a reduced operating time.