• Journal of Biomedical Engineering Research
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• v.23 no.3
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• pp.253-261
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• 2002

A spatially adaptive falter was formulated to imrove PET image qualify and the Performance of the filter was evaluated using simulation and phantom and human PET studies. In the proposed filter. if a pixel was identified as the edge Pixel, the Pixel value was Preserved. Otherwise a Pixel was replaced by the mean of the pixel values weighted by 2:7: 2. A Pixel was identified as the edge Pixel. if it satisfies the following conditions : the number of ADs (absolute difference between center and neighborhood pixels) which is smaller than THl (($pix_max{\times}0.1/log_2(NPM)$, NPM : mean of 6 neighborhood pixels excluding minimum and maximum) is 8-k and the number of ADs which is lager than TH2 ($NPM{\times}0.1$) is k. where k : 2, 3, …, 6. The results of this study demonstrate the superior performance of the Proposed titter compared to Gaussian fitter, weight median filter and subset averaged median filter. The proposed tittering method is simple but effective in increasing uniformity and contrast with minimal degradation of spatial resolution of PET images and thus. is expected to Provide improved diagnositc quality PET images .

• Journal of Korean Orthopaedic Sports Medicine
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• v.2 no.2
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• pp.142-148
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• 2003

Purpose: This study was performed to evaluate the operative results of osteochondritis dissecans treated with autogenous osteochondral grafts. Materials and Methods: From May 1990 to May 2000, this study included 13 patients, 17 cases treated with autogenous osteochondral grafts. The mean age of patients at operation was 23.4 years (range,20 to 32 years), all cases were men, and the mean follow-up was for 24.2 months (range, 12 to 110 months). Treatment was done by open or arthroscopic method using with Osteochondral Autograft Transfer System (OATS, Arthrex, USA). Results: Trauma history existed in all cases, and major trauma history in 7 cases, and minor repetitive in 10 cases. The involved sites of lesion were medial femoral condyle in 11 cases, in which extended classic site was 9 cases, inferocentral site was 2 cases, and lateral femoral condyle in 6 cases, in which all cases were inferocentral site. Magnetic resonance imaging (MRI) staging was stage II in 1 case, stage III in 11 cases, stage IV in 5 cases, and arthroscopic staging was stage III in 12 cases, stage IV in 5 cases. The mean lesion size was 3.19$cm^2$ (range, 1 to 8$cm^2$). Clinical results evaluated with grading system by Aichroth, were excellent in 3 cases (18$\%$), good in 11 cases (65$\%$), moderate in 2 cases (12V), poor in 1 case (5$\%$), which revealed satisfactory results in 83$\%$. Congruent articular surface, satisfactory articular thickness, and no loosening or subsidence was evidenced by follow-up MRI or arthroscopic finding. Conclusion: Autogenous osteochondral grafts can be an alternative treatment in lesions larger than 1$cm^2$ in size, unstable lesion, and involvement of weight-bearing articular surface. Long term follow-up will be needed for the final efficacy of autogenous osteochondral grafts.

• Clinics in Shoulder and Elbow
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• v.14 no.1
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• pp.59-66
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• 2011

Purpose: We wanted to evaluate the clinical and radiological outcomes and the prognosis of various surgical treatments for the distal clavicle fracture with an acromioclavicular joint injury. Materials and Methods: A retrospective study of 21 patients with a minimum of 12 months follow up was done. We classified acromioclavicular (AC) injury into type I (only intra-articular fracture (IAF), 5 cases), type II (IAF with widening of the AC joint > 7 mm, 9 cases) and type III (IAF with AC joint superior subluxation > 50%, 7 cases). The distal clavicle fractures were fixed using plate (9 cases), mini screws (1 case), K wire and tension band wiring (10 cases) and transarticular pinning (1 case). Acromioclavicular or coracoacromial ligament reconstruction was not done in all the cases. Results: In 20 of 21 cases, bone union was achieved at an average of 8.4 weeks. Traumatic arthritis (5 cases), AC joint widening (4 cases) and AC joint subluxation (2 cases) were noted at the last follow up. The average UCLA score was 32.6 in the type I AC joint injuries, 34 in type II and 34.1 in type III. There was no relationship between the clinical outcomes and the preoperative AC joint injury pattern, postoperative traumatic arthritis, AC joint widening or AC joint subluxation (p>0.05). Conclusion: Satisfactory results were achieved by acute reduction and firm fixation of the distal clavicle fracture with AC joint injury. There was no relationship between the pattern of AC joint injury, the residual radiologic findings and the functional outcome.

• Journal of Chest Surgery
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• v.40 no.8
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• pp.546-551
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• 2007

Background: The radial artery is gaining widespread acceptance as complementary arterial conduits for surgical myocardial revascularization, but there have been limited reports about its angiographic patency compared with that of internal thoracic artery or saphenous vein. We tried to evaluate angiographic patency of radial artery graft and to compare that of radial artery and other gratis with retrospective manner. Material and Method: From January 2001 to Jure 2006, totally 132 patients (male 92, female 40) who underwent coronary artery bypass graft using radial artery were re-admitted to our hospital for follow up angiographic examination. Mean age was 58.2+8.87 and mean follow up duration was 32 month ($2{\sim}110$ month). Off pump and on pump bypass surgery were performed 74 and 58 patients respectively. Along with radial artery, left internal thoracic arteries were used in 57 cases, concomitant left internal thoracic artery and saphenous veins were used in 47 cases and bilateral internal thoracic arteries were used in 20 cases. Result: Totally 412 distal anastomosis were performed and 376 anastomosis remained patent (91.2%). Left internal thoracic artery showed the most excellent patency in all of the conduits (98.5%). Radial artery graft patency was 90.8% (169/186). There was no statistical difference of the patency by conduit between on-pump and off-pump group. But radial artery showed more higher patency rate (98/110, 89%) in the severe stenotic lesion that preoperatively revealed more than 90% stenosis than in the lesser severe (<90%) stenotic lesion (60/76, 78%)(p < 0.005). Radial artery conduit represented the worst result when it was grafted in the right coronary system. But when it was positioned in the left heart especially diagonal or obtuse marginal area, patency was comparable with left internal thoracic artery. Conclusion: Radial artery graft showed good midterm patency when it was used in the severe stenotic lesion more than 90% and left coronary system. But great notice should be taken when it is grafted in the right coronary system or less severe stenotic lesion.

• Korean Journal of Environmental Agriculture
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• v.22 no.2
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• pp.148-152
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• 2003

The phosphorus(P) adsorption capacities of various filter media were investigated in relation to the size and types of fitter media to screen the optimum condition. The objective of this study was to evaluate the constructed wetland longevity by improving P adsorption capacity. The maximum P adsorption capacities of filter media A($4{\sim}10\;mm$), B($2{\sim}4\;mm$) and C($0.1{\sim}2\;mm$) were 8, 10 and 22 mg/kg, respectively, showing those increased as the filter media size decreased. Among the experimental media, the optimum filter media size was $0.1{\sim}2\;mm$. When the filter Medium was supplemented with organic materials which were piled up and decayed in the constructed wetland, the P adsorption capacity was significantly enhanced Under the conditions of optimum fitter media size, the respective Maximum P adsorption capacities of filter media C when supplemented with Ca, Mg, Al and Fe were higher than that of filter media C. However the addition of Ca, Mg, Al and Fe to constructed wetland were not recommended because of the possibility of their secondary pollution. The maximum P adsorption capacity of filter media C was 22 mg/kg, but this was increased to 36 mg/kg when filter media C was supplemented with 2% oyster shell.

• Science of Emotion and Sensibility
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• v.8 no.1
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• pp.17-28
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• 2005

With the advent of computer technology, the fundamental nature of products has shaped from physical forms towards product interactivity, The focus is now on usability of the product with ease and efficiency rather than conversing with just the looks of the product. However, most definitions of usability and contemporary usability-related researches, have focused on the performance-oriented functional aspects of usability (i.e., how well users perform tasks using a product). Today, user expectations are higher; products that bring not only functional benefits but also emotional satisfaction. So far, there have been many studies on human emotions and the emotional side of products in the field of emotional engineering. Contemporary emotion-related researches have focused mainly on the relationship between product aesthetics and the emotional responses elicited by the products, but little is known about emotions elicited from using the products. The main objective of our research is analyzing user's emotional changes while using a product, to reveal the influence of usability on human emotions. In this research, we suggested conceptual framework for the study on the relationship between usability of products, and human emotions with emphasis on mobile phones. We also extracted emotional words for measuring user's emotions expressed not from looking at the product's appearance, but from using the product. First, we assembled a set of emotions that is sufficiently extensive to represent a general overview of the full repertoire of Korean emotions from the literature study. Secondly, we found emotional words in the after note by the users on the websites. Finally, verbal protocols in which the user says out loud what he/she ks feeling while he/she ks carrying out a task were collected. And then, the appropriateness of extracted emotional words was verified by the members of the consumer panel of a company through web survey. It is expected that emotional words extracted in this research will be used to measure user's emotional changes while using a product. Based on the conceptual framework suggested in this research, basic guidelines on interface design methods that reflect user's emotions will be illustrated.

• Journal of Life Science
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• v.22 no.11
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• pp.1456-1462
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• 2012

Sorafenib is a multikinase inhibitor and an oral anticancer drug approved for the treatment of patients with advanced renal cell carcinoma and those with unresectable hepatocellular carcinoma. The purpose of this study was to develop an efficient method of the determination of sorafenib in human plasma using tandem mass spectrometry coupled with liquid chromatography (LC/MS/MS) and validate the method by the guidelines of the Korean Food and Drug Administration (KFDA). Plasma samples ($100{\mu}l$) were added with chlorantraniliprole as an internal standard and then mixed with the 0.1% formic acid-containing extraction solution composed of isopropyl alcohol and ethyl acetate (1:4, v/v). After centrifugation, the supernatant was concentrated at $45^{\circ}C$ under negative pressure and centrifugal force. The residue was reconstituted with a mobile phase and injected into the HPLC instrument using a reverse phase Waters XTerra$^{TM}$ C18 column (particle size $3.5{\mu}m$). Liquid chromatography was carried out within the run time of 5 min using a mobile phase composed of buffer (0.1% formic acid and 10 mM ammonium formate), methanol, and acetonitrile (1:6:3, v/v/v). The analytes were monitored by tandem mass spectrometry in the multiple reaction monitoring method programmed to detect sorafenib at 'm/z 465.2 ${\rightarrow}$ 252.5' and chlorantraniliprole at 'm/z 484.4 ${\rightarrow}$ 286.2' with positive electrospray ionization mode ($ES^+$). The result showed the proper linearity ($r^2$ > 0.99) over the range of 2,000-5,000 ng/ml with good accuracy (90.7-103.9%) and precision (less than 10%). The newly developed method using LC/MS/MS was validated by the guideline of KFDA and identified as more sensitive compared to the previous methods.

• The Journal of Korean Society for Radiation Therapy
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• v.26 no.1
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• pp.11-19
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• 2014

Purpose : To derive the most appropriate factors by considering the effects of the major factors when applied to the optimization algorithm, thereby aiding the effective designing of a ideal treatment plan. Materials and Methods : The eclipse treatment planning system(Eclipse 10.0, Varian, USA) was used in this study. The PBC (Pencil Beam Convolution) algorithm was used for dose calculation, and the DVO (Dose Volume Optimizer 10.0.28) Optimization algorithm was used for intensity modulated radiation therapy. The experimental group consists of patients receiving intensity modulated radiation therapy for the head and neck cancer and dose prescription to two planned target volume was 2.2 Gy and 2.0 Gy simultaneously. Treatment plan was done with inverse dose calculation methods utilizing 6 MV beam and 7 fields. The optimal algorithm parameter of the established plan was selected based on volume dose-priority(Constrain), dose fluence smooth value and the impact of the treatment plan was analyzed according to the variation of each factors. Volume dose-priority determines the reference conditions and the optimization process was carried out under the condition using same ratio, but different absolute values. We evaluated the surrounding normal organs of treatment volume according to the changing conditions of the absolute values of the volume dose-priority. Dose fluence smooth value was applied by simply changing the reference conditions (absolute value) and by changing the related volume dose-priority. The treatment plan was evaluated using Conformal Index, Paddick's Conformal Index, Homogeneity Index and the average dose of each organs. Results : When the volume dose-priority values were directly proportioned by changing the absolute values, the CI values were found to be different. However PCI was $1.299{\pm}0.006$ and HI was $1.095{\pm}0.004$ while D5%/D95% was $1.090{\pm}1.011$. The impact on the prescribed dose were similar. The average dose of parotid gland decreased to 67.4, 50.3, 51.2, 47.1 Gy when the absolute values of the volume dose-priority increased by 40,60,70,90. When the dose smooth strength from each treatment plan was increased, PCI value increased to $1.338{\pm}0.006$. Conclusion : The optimization algorithm was more influenced by the ratio of each condition than the absolute value of volume dose-priority. If the same ratio was maintained, similar treatment plan was established even if the absolute values were different. Volume dose-priority of the treatment volume should be more than 50% of the normal organ volume dose-priority in order to achieve a successful treatment plan. Dose fluence smooth value should increase or decrease proportional to the volume dose-priority. Volume dose-priority is not enough to satisfy the conditions when the absolute value are applied solely.

• The KIPS Transactions:PartC
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• v.13C no.1 s.104
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• pp.83-94
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• 2006

This paper describes ATM cell encipherment method using Rijndael Algorithm adopted as an AES(Advanced Encryption Standard) by NIST in 2001. ISO 9160 describes the requirement of physical layer data processing in encryption/decryption. For the description of ATM cell encipherment method, we implemented ATM data encipherment equipment which satisfies the requirements of ISO 9160, and verified the encipherment/decipherment processing at ATM STM-1 rate(155.52Mbps). The DES algorithm can process data in the block size of 64 bits and its key length is 64 bits, but the Rijndael algorithm can process data in the block size of 128 bits and the key length of 128, 192, or 256 bits selectively. So it is more flexible in high bit rate data processing and stronger in encription strength than DES. For tile real time encryption of high bit rate data stream. Rijndael algorithm was implemented in FPGA in this experiment. The boundary of serial UNI cell was detected by the CRC method, and in the case of user data cell the payload of 48 octets (384 bits) is converted in parallel and transferred to 3 Rijndael encipherment module in the block size of 128 bits individually. After completion of encryption, the header stored in buffer is attached to the enciphered payload and retransmitted in the format of cell. At the receiving end, the boundary of ceil is detected by the CRC method and the payload type is decided. n the payload type is the user data cell, the payload of the cell is transferred to the 3-Rijndael decryption module in the block sire of 128 bits for decryption of data. And in the case of maintenance cell, the payload is extracted without decryption processing.

• Journal of agricultural medicine and community health
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• v.28 no.1
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• pp.39-51
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• 2003

Objectives: The oriental medical care has been getting popular in community health centers because of uniqueness, changing of disease patterns, and increasing of elderly population. From 1998, oriental medical doctors has been working in several rural community health centers for their military obligations. At this point of time, it is necessary to evaluate the oriental public health doctors system. This study was performed to investigate the utilization patterns, the degree of satisfactions, needs of oriental medical care service provided by community health center in a designated Gun area. This study focused on the need for extending over Myun area of community health center's oriental medical care services. Methods: Person-to-person interview survey method through a structured questionnaire was done by a personnel at a oriental medical care service room in a Gun community health center. The major statistical method used for the analysis were the t-test, ANOVA, and logistic analysis. Results: The total number of responded subjects in this study was 163 residents. Among these 65.0% were aged 61 or over, and only 13.5% recognized themselves were healthy. 73.7% of the respondents demanded establishment of more oriental medical care services provided by community health center to other Myun area. Factors affecting the need for enlargement of oriental medical care service room were education level, subjective awareness of access to community health center, and cost satisfaction of oriental medical service provided by community health center. Thus, a resident who had graduation of middle school achievement or above(OR=3.35), had a long way to center(OR=2.47), satisfied with oriental medical service cost(OR=2.78) had demonstrated increased chance of need by logistic regression analysis.