• KSCI Review
• /
• v.14 no.2
• /
• pp.205-214
• /
• 2006

Is need Remote Access through internet for business of Ubiquitous Computing age, and apply OTP for confidentiality about inputed ID and Password, network security of integrity. Current OTP must be possessing hardware or Token, and there is limitation in security. Install a Snooping tool to OTP network in this treatise, and because using Cain, enforce ARP Cache Poisoning attack and confirm limitation by Snooping about user password. Wish to propose new system that can apply Tokenless OTP by new security way, and secure confidentiality and integrity. Do test for access control inflecting Tokenless OTP at Remote Access from outside. and could worm and do interface control with certification system in hundred. Even if encounter hacking at certification process, thing that connection is impossible without pin number that only user knows confirmed. Because becoming defense about outward flow and misuse and hacking of password when apply this result Tokenless OTP, solidify security, and evaluated by security system that heighten safety.

• Journal of Korea Water Resources Association
• /
• v.43 no.7
• /
• pp.645-655
• /
• 2010

In this study, occurrences of relative probabilistic changing points between Chukwooki rainfall data (CWK) and modern rain gage data (MRG) were analyzed using Barry and Hartigan (BH) Bayesian changing points estimation method which estimated the changing points by calculation of change probabilities at each point. Since any natural phenomenon cannot be simulated identically and perfectly, a statistical method which can not consider the sequential order has its limitation on prediction of a specific time of occurrence. In this respect, Homogeneity analysis between CWK and MRG was performed through the occurrence investigation of relative probabilistic changing points for four rainfall characteristics of data sets using BH bayesian model which estimate the change point by calculating the relative probabilities in each data points. The results show that statistical characteristics of CWK are not different significantly from MRG, even though considered that there may be little quantitative difference CWK and MRG caused from limitation of measurement accuracy of CWK.

• Smart Structures and Systems
• /
• v.13 no.6
• /
• pp.975-991
• /
• 2014

The objective of this study is to develop a reliable method for locating cracks in a beam using data fusion of fractal dimension features of operating deflection shapes. The Katz's fractal dimension curve of an operating deflection shape is used as a basic feature of damage. Like most available damage features, the Katz's fractal dimension curve has a notable limitation in characterizing damage: it is unresponsive to damage near the nodes of structural deformation responses, e.g., operating deflection shapes. To address this limitation, data fusion of Katz's fractal dimension curves of various operating deflection shapes is used to create a sophisticated fractal damage feature, the 'overall Katz's fractal dimension curve'. This overall Katz's fractal dimension curve has the distinctive capability of overcoming the nodal effect of operating deflection shapes so that it maximizes responsiveness to damage and reliability of damage localization. The method is applied to the detection of damage in numerical and experimental cases of cantilever beams with single/multiple cracks, with high-resolution operating deflection shapes acquired by a scanning laser vibrometer. Results show that the overall Katz's fractal dimension curve can locate single/multiple cracks in beams with significantly improved accuracy and reliability in comparison to the existing method. Data fusion of fractal dimension features of operating deflection shapes provides a viable strategy for identifying damage in beam-type structures, with robustness against node effects.

• Journal of Korean Neurosurgical Society
• /
• v.50 no.4
• /
• pp.363-369
• /
• 2011

Objective : We investigated the clinical and radiological advantages of unilateral laminectomy in posterior lumbar interbody fusion (PLIF) procedure comparing with bilateral laminectomy, under the same procedural condition including bilateral instrumentation and insertion of two cages, in patients with degenerative lumbar disease with unilateral leg symptoms. Methods : We retrospectively reviewed 124 consecutive cases of PLIF via unilateral or bilateral approach between January 2006 and April 2010. In 80 cases (bilateral group), two cages were inserted via bilateral laminectomy, and in 44 cases (unilateral group), via unilateral laminectomy. The average follow-up duration was 29.5 months. The clinical outcomes were evaluated with the Visual Analogue Scale (VAS) and the Oswestry disability index (ODI). The fusion rates and disc space heights were determined by dynamic standing radiographs and/or computed tomography. Operative times, intra-operative and post-operative blood losses and hospitalization periods were also evaluated. Results : In clinical evaluation, the VAS and ODI scores showed excellent outcomes in both groups. There were no significant differences in term of fusion rate, but the perioperative blood loss and the operative time of the unilateral group were lower than that of the bilateral group. Conclusion : Unilateral laminectomy can minimize the operative time and perioperative blood loss in PLIF procedure. However, the different preoperative disc height between two groups is a limitation of this study. Despite this limitation, solid fusion and satisfactory symptomatic improvement could be achieved uniquely by our surgical method. This surgical method can be an alternative surgical technique in patients with unilateral leg pain.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• v.23 no.1
• /
• pp.95-102
• /
• 2001

Temporomandibular ankylosis is defined as a situation in which the condyle is fused to the fossa by bone or fibrous tissue. Conditons such as trauma, infection, or systemic disease may predispose to various types of ankylosis, bringing about different levels of limitation in mandibular movement. Most patients with temporomandibular ankylosis are associated with limitation of maximal mouth opening, deviation of the chin toward the affected side, impaired occlusion, chronic pain, compromised oral hygiene, severe facial asymmetry & impeded mandibular molar eruption occurring in childhood. Several techniques to release ankylosis have been described in the literature, showing variable and often unsatisfactory results. The most frequently used operations are gap arthroplasty, interpositional arthroplasty, and exicision and joint reconstruction with autogenous or alloplastic materials. We have managed the two patients of TMJ ankylosis. They had previously TMJ surgery and we treated with gap arthroplasty & active physial therapy. We have obtained favorable results and report these cases with literatures review.

• Journal of Oral Medicine and Pain
• /
• v.20 no.2
• /
• pp.407-420
• /
• 1995

This study was performed to evaluate and compare conservative treatment results by several parameters such as age, sex, symptom duration, type and timing of joint sound, parafunctional habits, splint type, and diagnostic classification. There have been too many articles reporting long term results of conservative treatment but articles related to comparison of treatment results by patients' self-evaluation have been rarely reported. For this study 258 patients with temporomandibular disorders(TMDs) were selected and examined by routine diagnostic procedure for TMDs. The subjects were classified into 5 TMDs subgroups ad treated with conservative treatments involving splints, physical modalities, jaw exercises, and counseling. Visual analogue scale(VAS) about pain, joint sound, and mouth opening limitation was recorded respectively during treatment period. From the VAS data and treatment duration, VAS treatment index(VAS Ti) was calculated. The obtained results were as follows : 1. Pain was the most frequent main symptom in subjects with temporomandibular disorders, and main symptom for mouth opening limitation was comparatively less than for pain or sound in disk displacement with reduction group or in degenerative joint disease group. 2. Degenerative joint disease group had the most poor treatment results and highest occlusal index of Helkim's index. 3. Good prognosis for conservative treatment was observed in acute group, under 6 months than chronic group, 6months over in symptom duration, and subjects with 40 years over in age showed the most poor prognosis. 4. Subjects treated with anterior repositioning splint had better treatment results than subjects treated with centric relation splint, but statistical significance in VAS Ti and treatment duration was not observed. 5. Treatment results according to affected side, types and point of joint sound did not show consistent statistical results. 6. The result for conservative treatment was observed poor in subjects with bruxism and clenching. 7. In studying coincidence between preferred chewing and affected side, frequency of preferred chewing side, in unilateral affection, was higher in ipsilateral than in contralateral side.

• Journal of Ecology and Environment
• /
• v.39 no.1
• /
• pp.31-42
• /
• 2016

The object of this study was to determine long-term temporal and spatial patterns of nutrients (nitrogen and phosphorus), suspended solids, and chlorophyll (Chl) in Chungju Reservoir, based on the dataset of 1992 - 2013, and then to develop the empirical models of nutrient-Chl for predicting the eutrophication of the reservoir. Concentrations of total nitrogen (TN) and total phosphorus (TP) were largely affected by an intensity of Asian monsoon and the longitudinal structure of riverine (Rz), transition (Tz), and lacustrine zone (Lz). This system was nitrogen-rich system and phosphorus contents in the water were relatively low, implying a P-limiting system. Regression analysis for empirical model, however, showed that Chl had a weak linear relation with TP or TN, and this was mainly associated with turbid, and nutrient-rich inflows in the system. The weak relation was associated with non-algal light attenuation coefficients (Kna), which is inversely related water residence time. Thus, values of Chl had negative functional relation (R² = 0.25, p < 0.001) with nonalgal light attenuation. Thus, the low chlorophyll at a given TP indicated a light-limiting for phytoplankton growth and total suspended solids (TSS) was highly correlated (R² = 0.94, p < 0.001) with non-algal light attenuation. The relations of Trophic State Index (TSI) indicated that phosphorus limitation was weak [TSI (Chl) - TSI (TP) < 0; TSI (SD) - TSI (Chl) > 0] and the effects of zooplankton grazing were also minor [TSI (Chl) - TSI (TP) > 0; TSI (SD) - TSI (Chl) > 0].

• Journal of The Korean Association For Science Education
• /
• v.37 no.2
• /
• pp.225-237
• /
• 2017

In this study, we investigated the characteristics of the individual processes of pre-service chemistry teachers in making written test items. For this, we analyzed the think-aloud processes of eight pre-service chemistry teachers while making six written test items about gas laws and their in-depth interview scripts. The characteristics of the processes were found to be divided into six categories; the lack of systemicity in planning stage for making written test items, the lack of awareness and consideration for the interrelationship between instruction and assessment, the diverse criteria in determining test item types, the difficulties in judging behavioral domains and difficulties of items in the table of specification, the limitation in using teacher's guides and misunderstanding of teacher's guides, and the limitation in point and/or content of review and differences depending on the time of review. These can provide some significant guidelines and implications in finding ways to improve pre-service chemistry teachers' ability to make written test items.

• Archives of Craniofacial Surgery
• /
• v.10 no.1
• /
• pp.23-28
• /
• 2009

Purpose: Blow out fracture can present tenderness, swelling, enophthalmos, extraoccular muscle limitation, paresthesia, diplopia according to severity of injury, so reconstruction of blow out fracture is important. Orbital soft tissue should be in orbit and defected orbital wall should be corrected by autologus tissue or alloplastic implants. Every implants have their merits and faults, every implants are used various. This study was designed to compare the sequelae of blow-out fracture repair using the alloplastic implants: micro-titanium mesh(Micro Dynamic titanium $mesh^{(R)}$, Leibinger, Germany), porous polyethylene ($Medpor^{(R)}$, Porex, USA), absorbable mesh plate(Biosorb $FX^{(R)}$ . Bionx Implants Ltd, Finland). Methods: Between January 2006 and April 2008, 52 patients were included in a retrospective study analysing the outcome of corrected inferior orbital wall fracture with various kind of implants. Implants were inserted through subciliary incision. Twenty patients were operated with micro-titanium mesh, fourteen patients with porous polyethylene and eighteen patients with absorbable mesh plate. In comparative category, enophthalmos, diplopia, range of motion of extraoccular muscle, inferior orbital nerve injury were more on frequently statistically in patients. Results: Fourteen of 18 patients underwent surgical repair to improve diplopia, 11 of 17 patients to improve parasthesia, 11 of 15 patients to improve enophthalmos, 8 of 9 patients to improve extraoccular muscle limitation. Duration of follow-up time ranged from 6 months to 12 months(mean, 7.4 months). There was no statistic difference of sequelae between micro titanium mesh and porous polyethylene and absorbable mesh plate in blowout fracture, inferior wall. Conclusion: There is no difference of sequelae between micro-titanium mesh, porous polyethylene and absorbable mesh plate in blow-out fracture, inferior wall. The other factors such as defect size, location, surgeon's technique, may influence the outcome of blow-out fracture repair.

• Archives of Craniofacial Surgery
• /
• v.9 no.2
• /
• pp.45-50
• /
• 2008

Purpose: Traditionally, titanium miniplate has been used for rigid fixation of mandible fractures. However, the limitations of metal plate have been reported such as hypersensitivity, interference with the cranio-facial growth of growing child, secondary bone resorption around the plate, foreign body reaction, declination of primary callus formation, and bone atrophy, and so forth. Recently, biodegradable miniplate has been introduced and used as an alternative to the metal plate despite of its lower strength. This study evaluated the usefulness and stability of biodegradable plate and screw for treatment of mandible fractures. Methods: In this study, 61 patients(92 areas) diagnosed as mandible fracture in the last 2 years have been reviewed. We used titanium plate and screw in 32 patients, and biodegradable plate and screw($INION^{(R)}$) in 29 patients. Stability of plates and screws, bony healing process and its side effects were observed by clinical and radiographic assessment. Results: In the titanium material group, one of malocclusion, two of mouth opening limitation, three of pain, three of palpation were shown. The plate of six patients involved in these complications were removed. In the biodegradable group, two of mouth opening limitation, two of pain, one of localized wound infection were shown and one plate was removed secondarily. Conclusion: There was no statistical difference between two groups in bony healing and complication rates. Biodegradable implants show efficient stability during initial bone healing and low side effects in long-term follow up periods.