• Journal of Intelligence and Information Systems
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• v.24 no.1
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• pp.205-225
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• 2018

Convolutional Neural Network (ConvNet) is one class of the powerful Deep Neural Network that can analyze and learn hierarchies of visual features. Originally, first neural network (Neocognitron) was introduced in the 80s. At that time, the neural network was not broadly used in both industry and academic field by cause of large-scale dataset shortage and low computational power. However, after a few decades later in 2012, Krizhevsky made a breakthrough on ILSVRC-12 visual recognition competition using Convolutional Neural Network. That breakthrough revived people interest in the neural network. The success of Convolutional Neural Network is achieved with two main factors. First of them is the emergence of advanced hardware (GPUs) for sufficient parallel computation. Second is the availability of large-scale datasets such as ImageNet (ILSVRC) dataset for training. Unfortunately, many new domains are bottlenecked by these factors. For most domains, it is difficult and requires lots of effort to gather large-scale dataset to train a ConvNet. Moreover, even if we have a large-scale dataset, training ConvNet from scratch is required expensive resource and time-consuming. These two obstacles can be solved by using transfer learning. Transfer learning is a method for transferring the knowledge from a source domain to new domain. There are two major Transfer learning cases. First one is ConvNet as fixed feature extractor, and the second one is Fine-tune the ConvNet on a new dataset. In the first case, using pre-trained ConvNet (such as on ImageNet) to compute feed-forward activations of the image into the ConvNet and extract activation features from specific layers. In the second case, replacing and retraining the ConvNet classifier on the new dataset, then fine-tune the weights of the pre-trained network with the backpropagation. In this paper, we focus on using multiple ConvNet layers as a fixed feature extractor only. However, applying features with high dimensional complexity that is directly extracted from multiple ConvNet layers is still a challenging problem. We observe that features extracted from multiple ConvNet layers address the different characteristics of the image which means better representation could be obtained by finding the optimal combination of multiple ConvNet layers. Based on that observation, we propose to employ multiple ConvNet layer representations for transfer learning instead of a single ConvNet layer representation. Overall, our primary pipeline has three steps. Firstly, images from target task are given as input to ConvNet, then that image will be feed-forwarded into pre-trained AlexNet, and the activation features from three fully connected convolutional layers are extracted. Secondly, activation features of three ConvNet layers are concatenated to obtain multiple ConvNet layers representation because it will gain more information about an image. When three fully connected layer features concatenated, the occurring image representation would have 9192 (4096+4096+1000) dimension features. However, features extracted from multiple ConvNet layers are redundant and noisy since they are extracted from the same ConvNet. Thus, a third step, we will use Principal Component Analysis (PCA) to select salient features before the training phase. When salient features are obtained, the classifier can classify image more accurately, and the performance of transfer learning can be improved. To evaluate proposed method, experiments are conducted in three standard datasets (Caltech-256, VOC07, and SUN397) to compare multiple ConvNet layer representations against single ConvNet layer representation by using PCA for feature selection and dimension reduction. Our experiments demonstrated the importance of feature selection for multiple ConvNet layer representation. Moreover, our proposed approach achieved 75.6% accuracy compared to 73.9% accuracy achieved by FC7 layer on the Caltech-256 dataset, 73.1% accuracy compared to 69.2% accuracy achieved by FC8 layer on the VOC07 dataset, 52.2% accuracy compared to 48.7% accuracy achieved by FC7 layer on the SUN397 dataset. We also showed that our proposed approach achieved superior performance, 2.8%, 2.1% and 3.1% accuracy improvement on Caltech-256, VOC07, and SUN397 dataset respectively compare to existing work.

• Clinical and Experimental Pediatrics
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• v.51 no.1
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• pp.33-41
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• 2008

Purpose : It is now understood that blood pressure (BP) measurement in the routine pediatric examination is very important because of the relevance of childhood BP to pediatric health care and the development of adult essential hypertension. There hasn't been a reference table of BP for Korean children and adolescents up to now. This study was to make normative BP references and to provide criteria of hypertension for Korean children and adolescents. Methods : BP measurements were done on 57,433 Koean children and adolescents (male: 29,443, female: 27,990), aged 7 to 20 years, in 2005. Heights and weights were measured simultaneously. Oscillometric devices, Dinamap Procare 200 (GE Inc., Milwaukee, Wi, USA), were used for the measurements. BPs were measured 2 times and mean levels were gathered for the analysis. Outliers of 2,373 subjects with overweight per height, over ＋3SD, were excluded for the analysis. For the BP centiles adjusted by sex, age and height, fixed modified LMS method which was adopted from the mixed effect model of 2004 Task Force in NHLBI (USA) was used. Results : Normative BP tables for Korean children and adolescents adjusted for height percentiles (5th, 10th, 25th, 50th, 75th, 90th, 95th), gender (male, female) and age(7 to 18 years) were completed. Height centiles of Korean children and adolescents are available from Korean Center for Disease Control and Prevention homepage, http://www.cdc.go.kr/webcdc/. Criteria of hypertension (95th, 99th percentile) and normal range of BP (50th, 90th) adjusted for height percentiles, age and gender were made. Conclusion : This is the first study to make normative BP tables and define hypertension for the Korean children and adolescents. Reliability and accuracy of Dinamap Procare 200 oscillometer for BP measurements remains debatable.

• Journal of the Korean earth science society
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• v.39 no.2
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• pp.119-130
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• 2018

Aerosol Optical Properties (AOPs) are retrieved using the geostationary satellite instruments such as Geostationary Ocean Color Imager (GOCI), Meteorological Imager (MI), and Advanced Himawari Imager (AHI) through Yonsei AErosol Retrieval algorithm (YAER). In this study, the retrieved aerosol optical depths (AOD)s from each instrument were intercompared and validated with the ground-based sunphotometer AErosol Robotic NETwork (AERONET) data. As a result, the four AOD products derived from different instruments showed consistent results over land and ocean. However, AODs from MI and GOCI tend to be overestimated due to cloud contamination. According to the comparison results with AERONET, the percentage within expected errors (EE) are 36.3, 48.4, 56.6, and 68.2% for MI, GOCI, AHI-minimum reflectivity method (MRM), and AHI-estimated surface reflectance from shortwave Infrared (ESR) product, respectively. Since MI AOD is retrieved from a single visible channel, and adopts only one aerosol type by season, EE is relatively lower than other products. On the other hand, the AHI ESR is more accurate than the minimum reflectance method as used by GOCI, MI, and AHI MRM method in May and June when the vegetation is relatively abundant. These results are explained by the RMSE and the EE for each AERONET site. The ESR method result show to be better than the other satellite product in terms of EE for 15 out of 22 sites used for validation, and they are better than the other product for 13 sites in terms of RMSE. In addition, the error in observation time in each product is found by using characteristics of geostationary satellites. The absolute median biases at 00 to 06 Universal Time Coordinated (UTC) are 0.05, 0.09, 0.18, 0.18, 0.14, 0.09, and 0.10. The absolute median bias by observation time has appeared in MI and the only 00 UTC appeared in GOCI.

• Journal of Chest Surgery
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• v.30 no.7
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• pp.656-662
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• 1997

Aortic valvuloplasty has recently gained attention as an attractive alternative procedure for aortic valvular disease. Between March 1995 to August 1996, 14 patients with pure aortic regurgitation(AR) underwent aortic alvuloplasty using leaflet extension with glutaraldehydepreserved autologous pericardium. There were 11 males and 3 females, and the mean age was 34.8 $\pm$ 15.3 years. Preoperative echocardiography and cardiac catheterization revealed that the degree of AR was mean 3.4$\pm$0.65, and more than moderate degree of mitral regurgitation(MR) were detected in 4 patients. In 12 patients, 3 leaflets were extended and in another 2 patients only one deformed leaflet was extended. Concomitant mitral valvuloplasty (MVP) was performed in 4 patients. The competency of the aortic valve after completion of repair was evaluated by the transesophageal echocardiography in operating theater, and there was no aortic and mitral stenosis or regurgitation. In an early postoperative echocardiography, trivial AR was detected in 3 patients and mild MR in 1 patient. The end-systolic and end-diastolic dimensions of the left ventricle were decreased significantly(p<0.05) as compared with those of preoperative values. T ere was no mortality and no significant postoperative complication encountered. Late complication developed in 2 patients during the follow-up period(mean 7.9$\pm$ 5.9 months). One patient underwent AVR on postoperative 7th month due to endocarditis, and the another patient with Behcet's disease underwent Ross operation at postoperative 4th month. In conclusion, AVP of leaflet extension technique offers an excellent early clinical result and represents a good alterna!ivy surgical treatment for the pure AR especially in young age group, although long-term follow-up is necessary to determine the durability of glutaraldehyde-preserved autologous pericardium as a valve leaflet.

• Korean Journal of Plant Resources
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• v.27 no.5
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• pp.546-555
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• 2014

The final aim of this study is to develop a biofiltration system integrated with plant vegetation for improving indoor air quality effectively depending on indoor space and characteristics. However, to approach this final goal, several requirements such as constant pressure drops (PDs) and soil moisture contents (SMCs), which influence the capacity design for a proper ventilation rate of biofiltration system, should be satisfied. Thus, this fundamental experiment was carried out to adjust a proper wind speed and to ensure a stabilization of initial SMCs within biofilter for uniform distribution of SMCs and PDs, and for normal plant growth, especially avoiding root stress by wind. Therefore, we designed horizontal biofliter models and manufactured them, and then calculated the ventilation rate, air residence time, and air-liquid ration based on the biofilter depending on three levels of wind speed (1, 2, and $3cm{\cdot}s^{-1}$). The relative humidity (RH) and PD of the humidified air coming out through the soil within the biofilter, and SMC of the soil and plant growth parameters of lettuce and duffy fern grown within biofilter were measured depending on the three levels of wind speed. As a result of wind speed test, $3{\cdot}sec^{-1}$ was suitable to keep up a proper RH, SMC, and plant growth. Thus, the next experiment was set up to be two levels of initial SMCs (low and high initial SMC, 18.5 and 28.7%) within each biofilter operated and a non-biofiltered control (initial SMC, 29.7%) on the same wind speed ($3cm{\cdot}sec^{-1}$), and measured on the RH and PD of the air coming out through the soil within the biofilter, and SMC of the soil and plant growth parameters of Humata tyermani grown within biofilter. This result was similar to the first results on RHs, SMCs, and PDs keeping up with constant levels, and three SMCs did not show any significant difference on plant growth parameters. However, two biofiltered SMCs enhanced dry weights of the plants slightly than non-biofiltered SMC. Thus, the stability of this biofiler system keeping up major physical factors (SMC and PD) deserved to be adopted for designing an advanced integrated biofilter model in the near future.

• Horticultural Science & Technology
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• v.33 no.4
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• pp.511-517
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• 2015

This research was conducted to evaluate the influence of root restriction materials and media on the growth of runner plantlets of 'Seolhyang' strawberry in a nursery field. To achieve this, the influence of three kinds of root media on the growth of runner plantlets was monitored when polyethylene film was used as the root restriction material. In addition, the influence of various root restriction materials (RRS) such as transparent polyethylene film (PE), non-woven fabric (NF), perforated polyethylene film (PP), and root proofing sheet (RPS) on the changes in volumetric water content (VWC) and temperature of root media as well as growth of runner plantlet were investigated when expanded rice hull (ERH) was used as the root medium. In the comparison of root media, growth parameters such as leaf area and crown thickness at 20 d after fixation as well as crown thickness and fresh weights of root and above-ground tissue at 40 d after runner plantlet fixation were higher in the ERH treatment than in sandy loam and loamy sand. When the influence of RRS was compared, the VWC of ERH was 55% just after irrigation, but decreased to 26% at just before irrigation. Ranges of the VWC as influenced by irrigation cycle were 16 to 10% in the PP and less than 10% in the NF and RPS. The soil temperature in the PE treatment was around $1^{\circ}C$ lower than in NF, PP, and RPS. The differences between day and night temperatures were also smaller in the PE treatment rather than those in NF, PP, and RPS. The growths of runner plantlet 50 d after fixation showed that plant heights as well as fresh weights of root and above-ground tissue were higher in the PE treatment than in NF, PP, and RPS. NF and PP did not effectively restrict roots inside the medium and the roots of runner plantlets penetrated through the root restriction materials resulting in the formation of root system below the restriction materials. The above results indicate that ERH is more effective than sandy loam or loamy sand as root medium. PE rather than NF, PP, or RPS as root restriction material resulted in better growth of runner plantlets in propagation of 'Seolhyang' strawberry. The results of this research will be used for production of high quality runner plantlets in strawberry propagation.

• The Journal of Korean Academy of Prosthodontics
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• v.48 no.2
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• pp.101-110
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• 2010

Purpose: This study has been conducted in order to examine the oral health status and dental prostheses status, and the effects of dental prostheses to the oral health related quality of life among the elderly using social welfare centers. Material and methods: For this purpose, the researcher conducted a questionnaire survey and oral examination of 275 samples of old persons using 7 social welfare centers located in Daejeon metropolitan city. The oral health related quality of life was measured by GOHAI (Geriatric Oral Health Assessment Index). Results: 1. The less age and the more education and the more subjective economic status and living with spouse of family status, the higher GOHAI showed. 2. Mean age of first using of removable denture is 62.11 years old and average life cycle of removable denture is 10.76years. 57.5% of study subjects use removable denture and complete denture user of study subjects are 13.8%. 3. In the case that they use fixed prostheses rather than removable ones and in the complete denture they use both sides (upper and lower) rather than single side, showed higher GOHAI. 4. In the case that they showed higher degrees of satisfaction with dental prostheses and can use them always and showed no necessity for new dental prostheses and denture adaptation is good, GOHAI showed higher. Conclusion: In order to improve oral health related quality of life among the elderly who have many missing teeth, it is required to restore their masticatory ability to the normal level by restoring the missing teeth which has lost its function through providing proper dental prostheses.

• Journal of the Korean Arthroscopy Society
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• v.16 no.1
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• pp.1-8
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• 2012

Purpose: To evaluate clinical and radiologic outcomes of transphyseal anterior cruciate ligament (ACL) reconstruction in patients with open physes who were selected with authors' new operative indications. Materials and Methods: We evaluated 15 patients with open physes who underwent a transtibial ACL reconstruction and were followed up for 4~6 years after surgery. Our operative indications involved 1) choronologic age of ${\geq}$ 16 in male and ${\geq}$ 14 in female, 2) open physes of ${\leq}$ 2 mm width, and 3) Risser sign and Tanner stage of ${\geq}$ 3. Tibialis anterior tendon allograft was used in all patients, and endobutton and bioscrew were used for femoral and tibial fixations, respectively. Functional outcomes were evaluated using Lysholm Knee Scoring scale, Tegner activity scale, and International Knee Documentation Committee (IKDC) 2000 subjective score. Physical examinations to evaluate stability involved Lachman and pivot shift tests. For radiographic results, we evaluated side to side differences of anterior displacement in stress views. In addition, with use of scannograms taken at last follow-up, we examined side to side differences of femorotibial angles, anatomical and mechanical lateral distal femoral angles, mechanical medial proximal tibial angles and leg lengths. Results: The mean Lysholm Knee score was 51(40-61) points preoperatively and 97(94-100) points at last follow up. The mean Tegner activity score was 2.6 points preoperatively and 7.1 points at last follow up. The mean IKDC score was 32.6 points preoperatively and 88.3 points at last follow up. The mean anterior displacement of the tibia was improved from 6.7(${\pm}1.0$) mm to 1.9(${\pm}0.9$) mm. There were no leg length discrepancies over 5 mm and no statistically significant differences in all the radiographic variables representing growth disturbance. Conclusion: This study suggests that patients with open physes who selected by authors' new indication would safely undergo transphyseal ACL reconstruction with successful outcomes.

• Journal of the Korean Arthroscopy Society
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• v.13 no.1
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• pp.46-52
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• 2009

Purpose: To evaluate the usefulness of minimally invasive arthroscopy-assisted plate removal of a laterally inserted periarticular distal femur plate used for the treatment of AO type-C distal femur fractures. Materials and Methods: From October 2002 to November 2005, we evaluated 17 patients whose plates were removed through minimally invasive arthroscopy-assisted plate-removal technique and 15 patients who got their plates removed through conventional method without using arthroscopy, 32 patients in total. All these patients included in this study initially underwent open reduction and internal fixation of the distal femoral fractures with a lateral plate, and complained of continued pain over the lateral femoral condyle after the fracture fixation. The average age was 42.6 (ranges: 20~66) and initial fracture types included 16 cases of C1, 11 cases of C2, and 5 cases of C3 following AO/ASIF classification guidelines. Measured outcomes included: associated intra-articular pathologies, time needed to return to activities of daily living, patients' overall satisfaction, complications following the removal of hardware, and pain before and 6 months after the operation. Results: The distal-most end of the plate was placed in the knee joint in all cases and damage of the lateral articular capsule was found in 23 cases. Continuous wound discharge after surgery was found in one case who underwent arthroscopy-assisted plate removal, and it was treated by irrigation and re-suture. Average time needed to return to activities of daily living was 7 days in arthroscopy assisted group and 7.6 days in conventionally removed group. Fourteen patients (82.4%) who underwent arthroscopyassisted plate-removal reported above 'fair' satisfaction and the Visual analog scale pain score decreased from 4.9 to 1.9, six months after the plate removal. Thirteen patients(86.7%) who underwent conventional plate removal reported above 'fair' satisfaction and the Visual analog scale pain score decreased from 5.2 to 2.5, six months after the operation. Conclusion: Through minimally invasive arthroscopic-assisted plate removal, intrarticular pathology of the knee joint was able to be simultaneously identified and treated at the time of hardware removal. Damage of lateral capsule of the knee joint caused by the inserted plate for the treatment of type C distal femoral fracture was very frequently found and following the plate removal, patients experienced an improvement in pain score. We therefore recommend routine lateral distal femoral plate removal if the bony union is attained in such cases as type C distal femoral fractures whose distal most end of the plates are located in the joint.

• Journal of Korean Orthopaedic Sports Medicine
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• v.6 no.2
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• pp.110-114
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• 2007

Purpose: This study evaluate clinical findings & management of rhabdomyolysis after strenuous activities in military police recruit. Materials and Methods: This study was carried out from June $1^{st}$, 2004 and May $23^{nd}$, 2005. The study subjects were 13 military police recruit patients who were admitted to our hospital with intractable muscle pain and swelling, and had suspicions of Rhabdomyolysis. The patients were given various blood tests (CPK, CK-MB, AST, BUN/Cr, and Electrolyte) and clinically observed. The patients were all males, and their average age was 20 $(19\sim21)$ years. Seven cases were due to push-up exercises, 5 was due to a soccer game, and 1 was due to riot control activities. The patients complained of swelling and tenderness in various parts of the extremities. Four complained of swelling and tenderness in forearm, 3 in upper arm, 1 in shoulder, and 5 in lower extremity. The diagnosis of rhabdomyolysis was made if the patient complained clinical symptom and had a blood CPK level of above 1,000 IU/L at the time of admission. Patients who took medication or had medical problem were excluded from this study. Bone scans were taken of all patients 4 hours after giving 99mTc-MDP 20mCi intravenously. Treatment was bed rest and fluid therapy. Patients who complained of excessive pain were given splint immobilization. Results: The average hospitalization day for the 13 patients was 20 days ($14\sim42$ days). Excluding one patient who exhibited ARF at time of admission, all patients showed a decrease of blood CPK below 1000 IU/L at an average hospitalization time of 8 days ($2\sim11$ days). The patient with ARF recovered after hemodialysis and fluid therapy. Conclusion: Patients complaining of swelling and severe muscle pain after excessive exercise or training should be suspicious of exercise induced rhabdomyolysis, and should be given blood tests and fluid therapy immediately.