• Journal of Intelligence and Information Systems
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• v.26 no.1
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• pp.97-117
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• 2020

Product evaluation criteria is an indicator describing attributes or values of products, which enable users or manufacturers measure and understand the products. When companies analyze their products or compare them with competitors, appropriate criteria must be selected for objective evaluation. The criteria should show the features of products that consumers considered when they purchased, used and evaluated the products. However, current evaluation criteria do not reflect different consumers' opinion from product to product. Previous studies tried to used online reviews from e-commerce sites that reflect consumer opinions to extract the features and topics of products and use them as evaluation criteria. However, there is still a limit that they produce irrelevant criteria to products due to extracted or improper words are not refined. To overcome this limitation, this research suggests LDA-k-NN model which extracts possible criteria words from online reviews by using LDA and refines them with k-nearest neighbor. Proposed approach starts with preparation phase, which is constructed with 6 steps. At first, it collects review data from e-commerce websites. Most e-commerce websites classify their selling items by high-level, middle-level, and low-level categories. Review data for preparation phase are gathered from each middle-level category and collapsed later, which is to present single high-level category. Next, nouns, adjectives, adverbs, and verbs are extracted from reviews by getting part of speech information using morpheme analysis module. After preprocessing, words per each topic from review are shown with LDA and only nouns in topic words are chosen as potential words for criteria. Then, words are tagged based on possibility of criteria for each middle-level category. Next, every tagged word is vectorized by pre-trained word embedding model. Finally, k-nearest neighbor case-based approach is used to classify each word with tags. After setting up preparation phase, criteria extraction phase is conducted with low-level categories. This phase starts with crawling reviews in the corresponding low-level category. Same preprocessing as preparation phase is conducted using morpheme analysis module and LDA. Possible criteria words are extracted by getting nouns from the data and vectorized by pre-trained word embedding model. Finally, evaluation criteria are extracted by refining possible criteria words using k-nearest neighbor approach and reference proportion of each word in the words set. To evaluate the performance of the proposed model, an experiment was conducted with review on '11st', one of the biggest e-commerce companies in Korea. Review data were from 'Electronics/Digital' section, one of high-level categories in 11st. For performance evaluation of suggested model, three other models were used for comparing with the suggested model; actual criteria of 11st, a model that extracts nouns by morpheme analysis module and refines them according to word frequency, and a model that extracts nouns from LDA topics and refines them by word frequency. The performance evaluation was set to predict evaluation criteria of 10 low-level categories with the suggested model and 3 models above. Criteria words extracted from each model were combined into a single words set and it was used for survey questionnaires. In the survey, respondents chose every item they consider as appropriate criteria for each category. Each model got its score when chosen words were extracted from that model. The suggested model had higher scores than other models in 8 out of 10 low-level categories. By conducting paired t-tests on scores of each model, we confirmed that the suggested model shows better performance in 26 tests out of 30. In addition, the suggested model was the best model in terms of accuracy. This research proposes evaluation criteria extracting method that combines topic extraction using LDA and refinement with k-nearest neighbor approach. This method overcomes the limits of previous dictionary-based models and frequency-based refinement models. This study can contribute to improve review analysis for deriving business insights in e-commerce market.

• Journal of the Korean Institute of Landscape Architecture
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• v.39 no.6
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• pp.1-11
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• 2011

The research was aimed to verify the feasibility of the model of Park-Based Mixed-Use Districts(PBMUD) around urban large park to secure private-based urban parks through the revision of the urban zoning system. The PBMUD is a type of urban zoning district in which park-oriented land use is mixed with the urban land uses of residents, advertising, business, culture, education and research. The PBMUD, delineated from and based on a new paradigm of landscape urbanism, is a new urban strategy to secure urban parks and to cultivate urban regeneration around parks and green spaces to enhance the quality of the urban landscape and to ameliorate urban environmental disasters like climate change. This study performed a questionnaire survey and analysis after a review of literature related to PBMUD. The study looked for specialists in the fields of urban planning and landscape architecture such as officials, researchers and engineers to respond to the questionnaire, which asked about degree of preference. The conclusions of this study were as follows. Firstly, specialists prefer the PBMUD at 79.3% for to 20.7% against ratio, indicating the feasibility of the model of PBMUD. The second, the most preferable reasons for the model, were the possibility of securing park space around urban parks and green spaces that assures access to park and communication with each area. The third, the main reason for non-preference for the model, was a lack of understanding of PBMUD added to the problems of unprofitable laws and regulations related to urban planning and development. These proposed a revision of the related laws and regulations such as the laws for planning and use of national land, laws for architecture etc. The fourth, the most preferred type of PBMUD, was cultural use mixed with park use in every kind of mix of land use. The degree of preference was lower in the order of use of commercial, residential, business, and education(research) when mixed with park use. The number of mixed-use amenities with in the park was found to be an indicator determining preference. The greater the number, the lower was preference frequencies, especially when related to research and business use. The fifth, the preference frequencies of the more than 70% among the respondents to the mixed-use ratio between park use and the others, was in a ratio of 60% park use and 40% other urban use. These research results will help to launch new future research subjects on the revision of zoning regulations in the laws for the planning and uses of national land and architectural law as well as criteria and indicators of subdivision planning as related to a PBMUD model.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.2
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• pp.205-212
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• 2012

This study was performed to investigate the prevalence of metabolic syndrome (MS) and assess nutrient intake levels for the purpose of improving MS risk factors. The participants in this study were 512 adults consisting of 271 men and 241 women aged 30 and over, who visited a public health center for a medical check up. The diagnosis of MS subjects was adapted from the NCEP-ATPIII guidelines and the WHO Asia-Pacific Area criteria for obesity. The MS group was defined as subjects displaying three or more risk factors, and the non MS group was defined as those displaying two or less risk factors. A dietary survey was conducted using the 24-hour recall method. The number of subjects displaying MS syndrome factors was 158 (30.9%), broken down into, 89 men and 69 women. Regarding risk factors in the MS group, the prevalence of waist circumference was 40.5%, hypertension 34.2%, hyperglycemia 31.0%, low HDL-cholesterol 24.7%, and hypertriglycemia 19.6%. BMI, sistolic blood pressure, blood glocose, blood triglyceride, and blood HCL-cholesterol of the MS group were significantly higher compared to the non MS group. Male subjects in the MS group reported high intakes of cereals, sugar, fruits, meat and poultry, oil and fats, and beverages and total food intake was significantly higher compared to the non MS group. Women in the MS group reported high intakes of meat and poultry, milk and dairy products, beverages, and seasonings, and total food intake was higher compared to the non MS group. Dietary diversity score (DDS) was 3.82~4.04, which was not significant among the groups. In men, dietary variety score (DVS) was 16.3 in the MS group and 19.4 in the non MS group, whereas in women, the DVS was 15.2 in the non MS group and 17.0 in the MS group. In GMVDF pattern, 11111 pattern was 30.7%, followed by 01111 for men and 11101 for women. Calorie, fat, and cholesterol intakes in men as well as, calorie, fat, and folate intakes in women in the MS group were higher compared to the non MS group. Intakes of protein, P, Fe, Na, vitamin $B_1$, vitamin $B_2$, niacin, vitamin E, and Zn were higher than the KDRIs. On the other hand, intakes of Ca, K, fiber, vitamin $B_2$, and vitamin C were below the KDRIs. Intakes of lipids, animal food, Na, and cholesterol in the MS group were higher compared to the non MS group, whereas intake of dietary fiber was lower. Our results indicate that continuous, systematic nutritional education program must implemented to reduce the risk factors associated with MS.

• The Korean Journal of Nuclear Medicine
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• v.32 no.1
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• pp.71-80
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• 1998

This study examines the levels of carbohydrate antigen 19-9(CA19-9) and cancer antigen 125(CA125) in serum and its related factors in healthy Korean population. Although CA19-9 and CA125 have been widely used tumor markers for gastroenteric cancers and ovarian cancer in Western countries, there are no information available on the serum levels of CA19-9 and CA125 in healthy population and the factors affecting the levels of these tumor markers in Korea. A cross-sectional study was performed to measure CA19-9 and CA125 among 76 healthy males and 95 healthy females in Korea. CA19-9 and CA125 were quantitated using solid-phase radioimmunoassay kits. Informations on the factors which might be related to the levels of these markers were collected by questionnaire(e.g., smoking, alcohol consumption, menstruation, oral pill use, breast-feeding history, etc.). There was no statistically significant difference in the mean of CA19-9 concentration between men(10.4 u/ml) and women(10.1 u/ml), whereas the mean of CA125 levels(11.2 u/ml) was higher in women than that(2.5 u/ml) in men. Although there was a statistically significant association between CA19-9 and average number of cigarette consumed per day(r=0.59, p=0.026) and total number of cigarettes consumed in women(r=0.74, p=0.003), the significance disappeared by multiple regression analysis after adjusting age and body mass index. Later age of menopause(p=0.035) and longer duration of breast-feeding(p=0.050) were significant predictors for CA125 levels in women by multiple regression analysis after adjusting age and body mass index. In conclusion, CA19-9 can be used as a stable tumor marker in clinical practices, however, menstruation and breast-feeding should be considered when CA125 is used in women.

• Radiation Oncology Journal
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• v.19 no.4
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• pp.335-344
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• 2001

Purpose : The aim of this study was to clarify the role of VEGF expression as an independent prognostic factor and to identify the patients at high risk for poor prognosis in stage IB cervical cancer. Materials and methods : A total of 118 patients with stage IB cervical cancer who had radical hysterectomy and pelvic lymph node dissection were included in the study. All known high risk factors of the patients were pathologically confirmed from the surgical specimen. Of the 118 patients, n patients were treated with postoperative radiotherapy and/or chemotherapy. VEGF expression was examined using immunohistochemistry in formalin-fixed, paraffin-embedded specimens of post-hysterectomy surgical materials. A semiquantitative analysis was made using a scoring system of 0, +, ++, and +++ for increasing intensity of stain. We classified the patients with scores from 0 to ++ as low VEGF expression and the patients with a score of +++ as high VEGF expression. Results : Of the 118 patients, 35 patients $(29.7\%)$ showed high VEGF expression. Strong correlations were found between the high VEGF expression and both deep stromal invasion (p=0.01) and the positive pelvic node (p=0.03). The 5-year overall and disease-free survival rates for all 118 patients were $95.5\%\;and\;93.8\%$. The 5-year overall (p=0.03) and disease-free survival (p<0.001) rates were $98.5\%\;and\;100%$ for low VEGF expression (0, +, and ++) and $85.5\%\;and\;79.7\%$ for high VEGF expression, respectively. Pelvic and distant failures for low versus high VEGF expression were $1.2\%$ versus $17.1\%$, (p=0.001) and $0\%$ versus $14.3\%$ (p<0.001), respectively. In a Cox multivariate analysis of survival, the high VEGF expression (p=0.02) and the bulky mass (p=0.02) were significant prognostic factors for overall survival. The high VEGF expression (p=0.002), and bulky mass (p=0.01) demonstrated as significant prognostic indicators for disease free survival. Conclusion : These results showed that VEGF expression was a highly significant predictor for pelvic and distant failure and the most significant prognostic factor of overall and disease free survival for the patients with stage IB cervix cancer treated with radical surgery. We strongly suggest that the immune-histochemistry for VEGF expression be performed in a routine clinical setting in order to identify the patients at high risk for poor prognosis in early stage cervical cancer. Furthermore, postoperative and/or chemotherapy did not reduce the pelvic failure and distant metastasis. To improve the cure rate for the patients with high VEGF expression in stage IB cervical cancer, antiangiogenic therapy including anti-VEGF Ab may be new treatment option.

• Journal of Food Hygiene and Safety
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• v.13 no.1
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• pp.53-61
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• 1998

This study was performed to investigate the antiulcer effects of Opuntia dillenii Haw. on the stomach ulcer induced by restraint and water-immersion stress in rats. For this experiment, 48 male Sprague-Dawley strain were used. The experimental groups were divided into four: a control (C) and 3 Opuntia dillenii Haw. treatment groups (E-1, E-2, E-3). Each dose of Opuntia dillenii Haw. was 30 mg/kg bw (E-1), 60 mgfKg bw (E-2) and 120 mg/kg bw (E-3). The rats were allocated to each group by 12 and observed for 4 weeks. The results were as following: 1. The stomach surface pH in each group showed no significant difference, but the values of Opuntia dillenii Haw. treatment groups were higher than the value of the control group. 2. The gastric wall mucus was increased in all Opuntia dillenii Haw. treatment groups compared with the control group. Especially in E-1 difference was higher (p<0.05) and in E-2 difference was significantly higher (p<0.01). 3. At shear rate 11.25, 45.0, 90.0, $225\;sec^{-1}$, whole blood viscosity and plasma viscosity were measured. Most of the values of Opuntia dillenii Haw. treatment groups were low compared with that of the control group. At shear rate 90.0, $225\;sec^{-1}$ the values of whole blood viscosity in E-1 were significantly low (p<0.05) and at shear rate 11.25, $45.0\;sec^{-1}$, more significant (p<0.01). At shear rate 11.25, 45.0, 90.0, $225\;sec^{-1}$ the values of whole blood viscosity in E-2 were significantly low (p<0.01). At shear rate $90.0\;sec^{-1}$ the value of plasma viscosity in E-1 was significantly low (p<0.05) and at shear rate 90.0, $225\;sec^{-1}$ the values of plasma viscosity in E-2 we resignificantly low (p<0.01). 4. Less severe ulcers were obsered in Opuntia dillenii Haw. treatment groups than in the control group. Especially E-1 groups tissues had only slight ulcers and necrosis of tissue was not observed in this group. From the results of this study, it can be concluded that the oral administratio-n of Opuntia dillenii Haw. results in protection of stomach ulcer by stimulating the secretion of gastric mucus and improving the gastric mucosal microcirculation.

• Journal of Intelligence and Information Systems
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• v.23 no.4
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• pp.147-168
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• 2017

There have been many studies on accurate stock market forecasting in academia for a long time, and now there are also various forecasting models using various techniques. Recently, many attempts have been made to predict the stock index using various machine learning methods including Deep Learning. Although the fundamental analysis and the technical analysis method are used for the analysis of the traditional stock investment transaction, the technical analysis method is more useful for the application of the short-term transaction prediction or statistical and mathematical techniques. Most of the studies that have been conducted using these technical indicators have studied the model of predicting stock prices by binary classification - rising or falling - of stock market fluctuations in the future market (usually next trading day). However, it is also true that this binary classification has many unfavorable aspects in predicting trends, identifying trading signals, or signaling portfolio rebalancing. In this study, we try to predict the stock index by expanding the stock index trend (upward trend, boxed, downward trend) to the multiple classification system in the existing binary index method. In order to solve this multi-classification problem, a technique such as Multinomial Logistic Regression Analysis (MLOGIT), Multiple Discriminant Analysis (MDA) or Artificial Neural Networks (ANN) we propose an optimization model using Genetic Algorithm as a wrapper for improving the performance of this model using Multi-classification Support Vector Machines (MSVM), which has proved to be superior in prediction performance. In particular, the proposed model named GA-MSVM is designed to maximize model performance by optimizing not only the kernel function parameters of MSVM, but also the optimal selection of input variables (feature selection) as well as instance selection. In order to verify the performance of the proposed model, we applied the proposed method to the real data. The results show that the proposed method is more effective than the conventional multivariate SVM, which has been known to show the best prediction performance up to now, as well as existing artificial intelligence / data mining techniques such as MDA, MLOGIT, CBR, and it is confirmed that the prediction performance is better than this. Especially, it has been confirmed that the 'instance selection' plays a very important role in predicting the stock index trend, and it is confirmed that the improvement effect of the model is more important than other factors. To verify the usefulness of GA-MSVM, we applied it to Korea's real KOSPI200 stock index trend forecast. Our research is primarily aimed at predicting trend segments to capture signal acquisition or short-term trend transition points. The experimental data set includes technical indicators such as the price and volatility index (2004 ~ 2017) and macroeconomic data (interest rate, exchange rate, S&P 500, etc.) of KOSPI200 stock index in Korea. Using a variety of statistical methods including one-way ANOVA and stepwise MDA, 15 indicators were selected as candidate independent variables. The dependent variable, trend classification, was classified into three states: 1 (upward trend), 0 (boxed), and -1 (downward trend). 70% of the total data for each class was used for training and the remaining 30% was used for verifying. To verify the performance of the proposed model, several comparative model experiments such as MDA, MLOGIT, CBR, ANN and MSVM were conducted. MSVM has adopted the One-Against-One (OAO) approach, which is known as the most accurate approach among the various MSVM approaches. Although there are some limitations, the final experimental results demonstrate that the proposed model, GA-MSVM, performs at a significantly higher level than all comparative models.

• The Korean Journal of Nuclear Medicine Technology
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• v.18 no.1
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• pp.43-48
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• 2014

Purpose: In the PET/CT images, The SUV (standardized uptake value) enables the quantitative assessment according to the biological changes of organs as the index of distinction whether lesion is malignant or not. Therefore, It is too important to enter parameters correctly that affect to the SUV. The purpose of this study is to evaluate an allowable error range of SUV as measuring the difference of results according to input errors of Activity, Weight, uptake Time among the parameters. Materials and Methods: Three inserts, Hot, Teflon and Air, were situated in the 1994 NEMA Phantom. Phantom was filled with 27.3 MBq/mL of 18F-FDG. The ratio of hotspot area activity to background area activity was regulated as 4:1. After scanning, Image was re-reconstructed after incurring input errors in Activity, Weight, uptake Time parameters as ${\pm}5%$, 10%, 15%, 30%, 50% from original data. ROIs (region of interests) were set one in the each insert areas and four in the background areas. $SUV_{mean}$ and percentage differences were calculated and compared in each areas. Results: $SUV_{mean}$ of Hot. Teflon, Air and BKG (Background) areas of original images were 4.5, 0.02. 0.1 and 1.0. The min and max value of $SUV_{mean}$ according to change of Activity error were 3.0 and 9.0 in Hot, 0.01 and 0.04 in Teflon, 0.1 and 0.3 in Air, 0.6 and 2.0 in BKG areas. And percentage differences were equally from -33% to 100%. In case of Weight error showed $SUV_{mean}$ as 2.2 and 6.7 in Hot, 0.01 and 0.03 in Tefron, 0.09 and 0.28 in Air, 0.5 and 1.5 in BKG areas. And percentage differences were equally from -50% to 50% except Teflon area's percentage deference that was from -50% to 52%. In case of uptake Time error showed $SUV_{mean}$ as 3.8 and 5.3 in Hot, 0.01 and 0.02 in Teflon, 0.1 and 0.2 in Air, 0.8 and 1.2 in BKG areas. And percentage differences were equally from 17% to -14% in Hot and BKG areas. Teflon area's percentage difference was from -50% to 52% and Air area's one was from -12% to 20%. Conclusion: As shown in the results, It was applied within ${\pm}5%$ of Activity and Weight errors if the allowable error range was configured within 5%. So, The calibration of dose calibrator and weighing machine has to conduct within ${\pm}5%$ error range because they can affect to Activity and Weight rates. In case of Time error, it showed separate error ranges according to the type of inserts. It showed within 5% error when Hot and BKG areas error were within ${\pm}15%$. So we have to consider each time errors if we use more than two clocks included scanner's one during the examinations.

• Radiation Oncology Journal
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• v.16 no.3
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• pp.265-274
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• 1998

Purpose : This prospective study has been conducted to assess the value of three dimensional conformal radiation therapy (3DCRT) for lung cancer and to determine its potential advantage over current treatment approaches. Specific aims of this study were to 1) find the most ideal 3DCRT technique 2) establish the maximum tolerance dose that can be delivered with 3DCRT and 3) identify patients at risk for development of radiation pneumonitis. Materials and Methods : Beginning in Nov. 1994, 95 patients with inoperable non-small cell lung cancer (stage I; 4, stage II; 1, stage IIIa; 14, stage IIIb; 76) were entered onto this 3D conformal trial Areas of known disease and elective nodal areas were initially treated to 45 Gy and then using 3DCRT technique 65 to 70 Gy of total dose were delivered to the gross disease. Sixty nine patients received 65 Gy of total dose and 26 received 70 Gy Seventy eight patients (82.1$\%$) also received concurrent MVP chemotherapy. 3DCRT plans were compared with 2D plans to assess the adequacy of dose delivery to target volume, dose volume histograms for normal tissue, and normal tissue complication Probabilities (NTCP). Results : Most of plans (78/95) were composed of non-coplanar multiple (4-8) fields. Coplanar segmented conformal therapy was used in 17 pateints, choosing the proper gantry angle which minimize normal lung exposure in each segment. 3DCRT gave the full dose to nearly 100$\%$ of the gross disease target volume in all patients. The mean NTCP for ipsilateral lung with 3DCRT (range; 0.17-0.43) was 68$\%$ of the mean NTCP with 2D treatment planning (range; 0.27-0.66). DVH analysis for heart showed that irradiated volume of heart could be significantly reduced by non-coplanar 3D approach especially in the case of left lower lobe lesion. Of 95 patients evaluable for response, 75 (79$\%$), showed major response including 25 (26$\%$) with complete responses and 50 (53$\%$) with partial responses. One and two rear overall survivals of stage III patients were 62.6$\%$ and 35.2$\%$ respectively. Twenty percent (19/95) of patients had pneumonitis; Eight patients had grade 1 pneumonitis and 11 other patients had grade 2. Comparison of the average of NTCP for lung showed a significant difference between patients with and without radiation pneumonitis. Average NTCP for Patients without complication was 62$\%$ of those with complications. Conclusions : This study showed that non-coplanar multiple fields (4-8) may be one of the ideal plans for 3DCRT for lung cancer. It also suggested that 3DCRT may provide superior delivery of high dose radiation with reduced risk to normal tissue and that NTCP can be used as a guideline for the dose escalation.

• Clinical and Experimental Pediatrics
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• v.45 no.5
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• pp.596-602
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• 2002

Purpose : The purpose of this study was to analyze the association of peripheral neutrophil count with the development of respiratory failure in preterm infants. Methods : A retrospective study was conducted from January 1993 to December 1999 on 44 preterm infants, who were admitted to the neonatal intensive care unit of St. Francisco hospital. Preterm infants(birth weight 500 to 1,350 gm) who had a complete blood count obtained within 2 hours after delivery. Patients in the lowest of neutrophil count(early neutropenia, < $1.0{\times}10^9/L$) were compared with patients in the remaining group. Results : Low neutrophil count were transient in early neutropenia group. The concentration the circulating neutrophil count rose from $0.85{\pm}0.11{\times}10^9/L$ at average of 2 hours after delivery to $5.3{\pm}2.7{\times}10^9/L$ at 24 hours after delivery in the early neutropenia group and from $3.6{\pm}1.6{\times}10^9/L$ to $5.8{\pm}3.2{\times}10^9/L$ in the non-neutropenia group during the same time period. Compare to the non-neutropenia group, the neutropenia group had a lower birth weight($1,046.50{\pm}180.76gm$ Vs $1,156.70{\pm}124.99gm$), a lower Apgar score(1 min : $3.41{\pm}1.18$ Vs $4.30{\pm}1.46$, 5 min : $5.41{\pm}0.87$ Vs $6.15{\pm}0.95$), and a higher incidence of bronchopulmonary dysplasia(27.27% Vs 7.0%). Patients who had early neutropenia were more likely to require mechanical ventilation, supplemental oxygen and hospital stay. Also, main effect factors for the two groups were birth weight(Odds ratio=5.457, 95% CI=1.551-27.525), initial peripheral blood white cells(odds ratio=8.308, 95% CI=2.054-52.699), and bronchopulmonary dysplasia(odds ratio=0.099, 95% CI=0.017-0.397). Conclusion : A low count of neutrophil in the systemic circulation of premature infants within 2 hours of birth is associated with more severe respiratory distress.