• Journal of Intelligence and Information Systems
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• v.17 no.4
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• pp.95-108
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• 2011

TThis is a study of the personalization method that intelligently adapts the level of clustering considering purchasing index of a customer. In the e-biz era, many companies gather customers' demographic and transactional information such as age, gender, purchasing date and product category. They use this information to predict customer's preferences or purchasing patterns so that they can provide more customized services to their customers. The previous Customer-Segmentation method provides customized services for each customer group. This method clusters a whole customer set into different groups based on their similarity and builds predictive models for the resulting groups. Thus, it can manage the number of predictive models and also provide more data for the customers who do not have enough data to build a good predictive model by using the data of other similar customers. However, this method often fails to provide highly personalized services to each customer, which is especially important to VIP customers. Furthermore, it clusters the customers who already have a considerable amount of data as well as the customers who only have small amount of data, which causes to increase computational cost unnecessarily without significant performance improvement. The other conventional method called 1-to-1 method provides more customized services than the Customer-Segmentation method for each individual customer since the predictive model are built using only the data for the individual customer. This method not only provides highly personalized services but also builds a relatively simple and less costly model that satisfies with each customer. However, the 1-to-1 method has a limitation that it does not produce a good predictive model when a customer has only a few numbers of data. In other words, if a customer has insufficient number of transactional data then the performance rate of this method deteriorate. In order to overcome the limitations of these two conventional methods, we suggested the new method called Intelligent Customer Segmentation method that provides adaptive personalized services according to the customer's purchasing index. The suggested method clusters customers according to their purchasing index, so that the prediction for the less purchasing customers are based on the data in more intensively clustered groups, and for the VIP customers, who already have a considerable amount of data, clustered to a much lesser extent or not clustered at all. The main idea of this method is that applying clustering technique when the number of transactional data of the target customer is less than the predefined criterion data size. In order to find this criterion number, we suggest the algorithm called sliding window correlation analysis in this study. The algorithm purposes to find the transactional data size that the performance of the 1-to-1 method is radically decreased due to the data sparity. After finding this criterion data size, we apply the conventional 1-to-1 method for the customers who have more data than the criterion and apply clustering technique who have less than this amount until they can use at least the predefined criterion amount of data for model building processes. We apply the two conventional methods and the newly suggested method to Neilsen's beverage purchasing data to predict the purchasing amounts of the customers and the purchasing categories. We use two data mining techniques (Support Vector Machine and Linear Regression) and two types of performance measures (MAE and RMSE) in order to predict two dependent variables as aforementioned. The results show that the suggested Intelligent Customer Segmentation method can outperform the conventional 1-to-1 method in many cases and produces the same level of performances compare with the Customer-Segmentation method spending much less computational cost.

• Journal of Chest Surgery
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• v.37 no.7
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• pp.591-596
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• 2004

Recently, thoracic sympathicotomy for craniofacial hyperhidrosis (FH) is increasingly avoided contrast to palmar hyperhidrosis. We recently demonstrated that selective T2 sympathicotomy for FH in woman might be recommended because of differences of the postoperative satisfaction between man and woman. Therefore, this study was designed to analyze the postoperative long term results, evaluate the effectiveness of T2 sympathicotomy and establish the new strategy in treatment of FH in woman. Material and Method: From May 1998 to July 2001, 27 cases of FH in woman that were performed T2 sympathicotomy and minimum 2 years have passed since then at the follow up period. Among them, 20 cases were evaluated by telephone review and medical record. Bilateral sympathetic trunks were severed on the 2nd rib with 2mm thoracoscopic instruments. 7 patients combined with gustatory sweating (GS). Ages ranged from 25 to 62 (mean age, 46.4 years). Result: All patients were relieved of symptom immediately after operation. At postoperative 1 week, all patients were satisfied: 15 patients, “very satisfaction” and 5 patients, “relatively satisfaction”. However, during long term follow up period (from 25 to 63 months postoperatively), 9 patients (45%) were relatively satisfied, 8 patients (40%) complained that there was no difference of postoperative satisfaction and 3 patients (15%) complained of non satisfactory results (regret for surgery). 16 patients (80%) had complaint of uncomfortable feeling because of postoperative GS. Some degree of compensatory sweating (CS) had occurred in all patients: severe 10 patients (50%), severe but acceptable 6 patients (30%), and just conventional 4 patients (20%). The sites of CS were trunk, back, axilla and extremities. Conclusion: Thoracoscopic T2 sympathicotomy is relatively considerable method for FH in woman and the postoperative satisfaction depends on GS and the degree of individual adaptation for CS. Therefore, it is required that the prediction of preoperative risk factors for GS and CS and then careful selection of patients to increase the postoperative satisfaction, and the development of acceptable new treatment modalities.

• Tuberculosis and Respiratory Diseases
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• v.67 no.1
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• pp.21-26
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• 2009

Background: Non-invasive positive pressure ventilation (NPPV) ensures adequate gas exchange during bronchoscopy in spontaneously breathing, hypoxemic patients, thus avoiding endotracheal intubation. However, in some patients, endotracheal intubation is eventually required after bronchoscopy. This study investigated the incidence of intubation and predictors of a need for emergency intubation prior to NPPV bronchoscopy initiation. Methods: On a retrospective basis, we reviewed the medical records of 36 patients (median age, 55 years; interquartile range [IQR], 43~65 years) with acute hypoxemic respiratory failure who required NPPV during bronchoscopy between January 2005 and October 2007. Results: All patients were hypoxemic (median $PaO_2/FiO_2$ ratio 155; IQR 90~190), but tolerated bronchoscopy with NPPV support. SOFA score and SAPS II score immediately before NPPV initiation were 4 (3~7) and 36 (30~42), respectively. Seventeen (47%) patients needed endotracheal intubation at a median time of 22 (2~50) hours after bronchoscopy. Patients who needed intubation after bronchoscopy had a higher in-hospital mortality (11 [65%] vs. 4 [21%], p=0.017). Upon multiple logistic regression analysis, the need for intubation after bronchoscopy was independently associated with a $P_aO_2/FiO_2$ ratio (OR, 0.961; 95% CI, 0.924~0.999; p=0.047) immediately before NPPV initiation for bronchoscopy. Conclusion: The severity of the hypoxemia immediately prior to NPPV initiation for bronchoscopy was associated with the need for intubation after bronchoscopy in patients with hypoxemic respiratory failure.

• Journal of the korean academy of Pediatric Dentistry
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• v.36 no.3
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• pp.337-347
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• 2009

Dental caries during infantile and early childhood period is a complex disease resulting from multiple caries factors. Streptococcus mutans(S. mutans) plays a critical role in the initiation of caries, and its early transmission through mothers provides a strong etiologic factor for future development of caries in the primary dentition. Therefore, early detection of caries risk factor is important for prevention of caries. Recent studies about etiologic factors of caries have brought advent of various tools for caries risk assessment in order to predict progress of caries more accurately. Cariogram is a common tool for caries risk assessment, which illustrates present caries risk assessment and correlation of caries risk factors for an individual graphically. The aim of this study was to assess if there is any correlation in the level of S. mutans and caries activity and to verify the effect of caries risk factors between children with age ranging from 3 to 5 years with severe early childhood caries(S-ECC) and their mothers using caries-related salivary test and Cariogram. The results of this study were as follows. 1. Children with S-ECC had a statistically higher level of Streptococcus mutans compared to caries-free children(p<0.05). 2. There was significant correlation between mothers and their children in the aspect of the level of Streptococcus mutans(p<0.05). 3. When caries activity was assessed using Cariogram, significant correlation between mothers and their children was found(p<0.05). 4. When each caries risk factor was evaluated for its affect on caries activity, host was more influential factor compared to microorganism and diet in children. Based on these results, we could conclude that assessing the level of S. mutans can be an effective tool for predicting possibility of caries formation in future. Since prediction of future caries progression and evaluation of caries risk factor became possible with Cariogram, we may conduct early and preventive measures for treatment of caries.

• Journal of Korean Society of Forest Science
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• v.99 no.1
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• pp.9-15
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• 2010

This study was conducted to develop a stand growth model and a stand yield table for Eucalyptus pellita and Acacia mangium plantations in Kalimantan, Indonesia. To develop a stand growth model, Weibull robability density function, a diameter class model, was applied in this study. In the development of stand growth model by site index and stand age, a hierarchy is generally required - estimation, recovery and prediction of the diameter class model. A number of grow equations were also involved in each process to estimate diameter, height, basal area, minimum or maximum diameter. To examine whether the grow equations are adequate for Eucalyptus pellita or Acacia mangium plantations, a fitness index was analyzed for each equation. The results showed that fitness indices were ranged from 65 to 89% for Eucalyptus pellita plantations and from 72 to 95% for Acacia mangium plantations. As being highly adequate for the plantations, a stand yield table was developed based on the resulted growth model, and applied to estimate the stand growth with midium site index for 10-year period. The highest annual stand growth of Eucalyptus pellita plantations was estimated to be 21.25 $m^3$/ha, while that of Acacia mangium plantations was 27.5 $m^3$/ha. In terms of annual stand growth, Acacia mangium plantations appeared to be more beneficial than Eucalyptus pellita plantations. Also, to estimate commercial timber volume available from the plantations, an assumption that a log would be cut by 2.7 m in length and the rest of the log would be cut by 1.5m was involved. The commercial timber volume available from Eucalyptus pellita plantations was 68.0 $m^3$/ha, 33% from the total stand volume, 203.2 $m^3$/ha. Also 96.7 $m^3$/ha of commercial timbers were available from Acacia mangium plantations, which was 42% from the 232.9 $m^3$/ha in total. Presenting a good information about the stand growth in Eucalyptus pellita and Acacia mangium plantations, this study might be useful for whom proceeds or considers an abroad plantation for merchantable timber production or carbon credit in tropical regions.

• Pediatric Infection and Vaccine
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• v.17 no.2
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• pp.169-176
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• 2010

Purpose : We aimed to evaluate predictive parameters for non-response to intravenous immunoglobulin (IVIG) in patients with Kawasaki disease (KD) before IVIG use using two controls. Methods : We evaluated 229 consecutive KD patients who were treated with 2 g/kg of IVIG at a single center. Those who had persistent fever >24 hours after IVIG infusion made up the 23 IVIG non-responders; the first control included a total 206 defervesced cases and the second control included 46 cases that were matched for age and pre-treatment fever duration to non-responders. Results : Demographic and clinical characteristics were similar in IVIG non-responders and responders at presentation. As for laboratory findings, the neutrophil differential, CRP, AST, ALT, and LDH were higher, and lymphocyte differential, total protein, albumin, platelet count, and total cholesterol were significantly lower in IVIG non-responders compared to responders by univariate analysis in both study designs. However in multivariate analysis, non-responders showed a significantly higher neutrophil differential (cutoff value, >77%, sensitivity 68.4% and specificity 79.5%) and lower cholesterol (<124 mg/dL, sensitivity 79% and specificity 70.5%). Whereas plasma albumin (<3.6 g/dL, sensitivity 73.7% and specificity 60%) was the sole laboratory parameter of non-responders in the second study design. Conclusion : Severity of inflammation in KD was reflected by higher or lower laboratory values at presentation. Because the multivariate analysis for these indices may be influenced by some confounding factors, including the numbers of patients of different ages and fever duration, other assessment modalities are needed for KD patients with the greatest risk of coronary artery lesions.

• The Korean Journal of Nuclear Medicine
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• v.31 no.4
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• pp.452-458
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• 1997

To evaluate the pinhole scintigraphic findings and its significance, authors retrospectively compared the pinhole bone scintigrams and corresponding radiograms of 16 lesions in 14 patients with fibrous dysplasia. They were diagnosed pathologically in 10 lesions and radiologically in 6 lesions. The mean age of patients was 41.1 years. The mean interval between two studies was 1.1 days. Locations were ribs 7, pelvic bone 4, clavicle 1, long bones 4(femur 2, tibia 1, humerus 1). The radiographic findings were as follows : the central portions were radiolucent(n=9), ground-glass opacities(n=5) or sclerotic(n=2) and the peripheral appearance were sclerotic rim(n=5), septation(n=7), cortical perforation (n=10) and invisible cortical thinning(n=9). Pinhole scintigraphic findings were as follows; Central portions showed normal 1+ uptake in 6 cases(radiolucent 5, ground-glass opacity 1), slightly increased 2+ upta- ke in 7 cases(radiolucent 4, ground-glass opacity 3), and marked 3+ uptake in 3 cases(ground-glass opacity 1, sclerotic 2). The 15 of 16 lesions showed more intense uptake in the peripheral portion: slightly increased 2+ uptake corresponding to the sclerotic rim(5/5) and unvisible cortical thinning(1/9), and irregular foci of marked 3 + uptake corresponding to septation(7/7), cortical perforation(10/10) and invisible cortical thinning (8/9). One of 16 lesions showed homogeneous 2+ uptake. In conclusion, pinhole scintigram provides information on regional activity of the fibrous dysplasia, which would be helpful in diagnosis, prediction of prognosis and determination of treatment plan.

• Journal of Hospice and Palliative Care
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• v.5 no.2
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• pp.125-135
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• 2002

Purpose : The purpose of this study was to investigate the impact of depression, discomfort, spirituality, physical care, and opioid use on pain with terminally ill cancer patients in the hospice units. Method : The convenient sample of this study consisted of 58 terminally ill cancer patients at three hospice units in university-affiliated hospitals. Patients were interviewed with structured questionnaires. The data was analyzed using ANOVA, Pearson correlation coefficient, and multivariate multiple regression. Result : The results of this study were as follows : 1) The mean age of the participants was approximately 57 years. Regarding diagnosis, stomach cancer showed the highest frequency (24.1%), followed by lung cancer (17.2%) and rectal cancer (13.8%). Regarding motivation for admission to the hospice unit, the majority of the participants indicated pain control (67.2%), followed by spiritual care (39.7%), and symptom relief (27.6%). 2) The mean pain level measured by VAS was 5.13 (${\pm}2.61$). Regarding pain type, the highest pain frequency the participants experienced was deep pain (53.4%), followed by multiple pain (20.7%), intestinal pain (17.3%), and neurogenic (5.2%) and superficial pain (3.4%). 3) Regarding the factors influencing pain, the pain level was significantly affected by the depression level (P<0.01) and the opioid use (P<0.01). Conclusion, In summary, the higher the level of pain the terminally ill cancer patents had the higher the depression level as well as the opioid use. Thus, health care professionals need to continuously provide holistic care for them to die comfortably.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.3 no.1
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• pp.1-8
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• 2000

Purpose: This study was undertaken to evaluate the clinical features and complication such as esophageal stricture in children with corrosive esophagitis. Methods: We retrospectively reviewed medical records of 31 children who accidentally ingested corrosive materials and visited to emergency room of Chonnam National University Hospital from Jan. 1992 to Dec. 1999. Twenty-one children were examined by upper gastrointestinal (UGI) endoscopy to evaluate location and severity of caustic injury. Results: 1) Among 31 patients, there were 20 males and 11 females and the ratio of male to female was 2:1. Average age at diagnosis was 2.3 years (12 months to 9.8 years). Twenty-seven (87.1%) patients were accidentally ingested vinegar. 2) Initial presenting symptoms were dysphagia (54.8%), vomiting (48.3%), chemical burn on lips and skin (45.2%), excessive salivation (45.2%), coughing and respiratory grunting (32.3%) and aspiration pneumonia (9.8%). 3) UGI endoscopic examination showed caustic injury in 17 children: grade I in 8, grade II in 7 and grade III in 2. The region of caustic injury was proximal esophagus in 5, distal esophagus in 3, entire esophagus in 9 and stomach in 6. 4) Corrosive esophageal strictures developed in 6 children (19.4%) and gastric outlet stricture in 1 (3.2%). All of them showed grade II or III caustic injury on endoscopic examination. Conclusion: The development of esophageal stricture was related to the severity of the caustic injury. Early UGI endoscopic examination in caustic ingestion seems to be useful for prediction of development of caustic stricture.

• Journal of Korean Society of Forest Science
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• v.104 no.3
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• pp.421-426
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• 2015

The objective of this paper is to look into the growth of Cryptomeria japonica stand in South Korea along with the evaluation on their yields, followed by their carbon stocks and removals. A total of 106 sample plots were selected from Jeonnam, Gyeongnam, and Jeju, where the groups of standard are grown. We only used 92 plots data except outlier. As part of the analysis, the Weibull diameter distribution was applied. In order to estimate the diameter distribution, the growth estimation equation for each of the growth factors including the height, the diameter at breast height, and the basal area was drafted out and the verification for each equation was examined. The site index for figuring out the forest productivity of Cryptomeria japonica stand for each district was also developed as a Schumacher model and 30yr was used as a reference age for the estimation of the site index. It was found that the site index for Cryptomeria japonica stand in South Korea ranges from 10 to 16 and this result was used as a standard for developing the stand yield table. According to the site 14 in the stand yield table, the mean annual increment (MAI) of the Cryptomeria japonica reaches $7.6m^3/ha$ on its 25yr and its growing stock is estimated to be at $190.1m^3/ha$. This volume is about $20m^3$ as high as that of the Chamaesyparis obtusa. Furthermore, the annual carbon absorptions for a Cryptomeria japonica stand reached the peak at 25yr, which is 2.14 tC/ha/yr, $7.83tCO_2/ha/yr$. When compared to the other conifers, this rate is slightly higher than that of a Chamaecyparis obtusa ($7.5tCO_2/ha/yr$) but lower than that of the Pinus koraiensis ($10.4tCO_2/ha/yr$) and Larix kaempferi ($11.2tCO_2/ha/yr$). With such research result as a base, it is necessary to come up with the ways to enhance the utilization of Cryptomeria japonica as timbers, besides making use of their growth data.