• Title/Summary/Keyword: Sequence Management

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Endoventricular Circular Patch Plasty (Dor Procedure) for Ischemic Left Ventricular Dysfunction (허혈성 좌심실 부전증에서의 좌심실내 원형 패취성형술)

  • Cho, Kwang-Ree;Lim, Cheong;Choi, Jae-Sung;Hong, Jang-Mee;Kim, Hyeong-Ryul;Kim, Ki-Bong
    • Journal of Chest Surgery
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    • v.37 no.9
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    • pp.755-761
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    • 2004
  • We evaluated the efficacy of Dor procedure in patients with ischemic left ventricular dysfunction. Material and Method: Between April 1998 and December 2002, 45 patients underwent the Dor procedure con-comitant with coronary artery bypass grafting (CABG). Left ventricular ejection fraction (LVEF) and left ventricular end-diastolic/end-systolic volumes (LVEDV/LVESV) were measured by echocardiography, myocardial SPECT, and cardiac catheterization and angiography performed at the sequence of preoperative, early postoperative, and one year postoperative stage. Result: Cardiopulmonary bypass and aortic clamp times were mean 141$\pm$64, 69$\pm$24 minutes, respectively. Intraaortic balloon pump (IABP) therapy was required in 19 patients (42%; 7 preoperatively, 9 intraoperatively, 3 postoperatively). Operative mortality rate was 2.2% (1/45). Postoperative morbidities were low cardiac output syndrome (12), atrial fibrillation (5), acute renal failure (4), and postoperative bleeding (4). Functional class (NYHA) was improved from classes 2.8 to 1.1 (p < 0,01). When we compared between the preoperative and early postoperative values, LVEF was improved from 32$\pm$9% to 52$\pm$11% (p<0.01). The asynergy portion decreased from 57$\pm$12% to 22$\pm$9%, and LVEDV/LVESV indexes improved from 125$\pm$39 mL/$m^2$, 85$\pm$30 mL/$m^2$ to 66$\pm$23 mL/$m^2$, 32$\pm$16 mL/$m^2$ (p<0.01). Although these changes in volumes were relatively preserved at postoperative one year, the left ventricular volumes showed a tendency to increase. Conclusion: After the Dor procedure for ischemic left ventricular dysfunction, LVEF improvement and left ventricular volume reduction were maintained till postoperative one year. The tendency for left ventricular volume to increase at postoperative one year suggested the requirement of strict medical management.

Analysis of Trading Performance on Intelligent Trading System for Directional Trading (방향성매매를 위한 지능형 매매시스템의 투자성과분석)

  • Choi, Heung-Sik;Kim, Sun-Woong;Park, Sung-Cheol
    • Journal of Intelligence and Information Systems
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    • v.17 no.3
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    • pp.187-201
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    • 2011
  • KOSPI200 index is the Korean stock price index consisting of actively traded 200 stocks in the Korean stock market. Its base value of 100 was set on January 3, 1990. The Korea Exchange (KRX) developed derivatives markets on the KOSPI200 index. KOSPI200 index futures market, introduced in 1996, has become one of the most actively traded indexes markets in the world. Traders can make profit by entering a long position on the KOSPI200 index futures contract if the KOSPI200 index will rise in the future. Likewise, they can make profit by entering a short position if the KOSPI200 index will decline in the future. Basically, KOSPI200 index futures trading is a short-term zero-sum game and therefore most futures traders are using technical indicators. Advanced traders make stable profits by using system trading technique, also known as algorithm trading. Algorithm trading uses computer programs for receiving real-time stock market data, analyzing stock price movements with various technical indicators and automatically entering trading orders such as timing, price or quantity of the order without any human intervention. Recent studies have shown the usefulness of artificial intelligent systems in forecasting stock prices or investment risk. KOSPI200 index data is numerical time-series data which is a sequence of data points measured at successive uniform time intervals such as minute, day, week or month. KOSPI200 index futures traders use technical analysis to find out some patterns on the time-series chart. Although there are many technical indicators, their results indicate the market states among bull, bear and flat. Most strategies based on technical analysis are divided into trend following strategy and non-trend following strategy. Both strategies decide the market states based on the patterns of the KOSPI200 index time-series data. This goes well with Markov model (MM). Everybody knows that the next price is upper or lower than the last price or similar to the last price, and knows that the next price is influenced by the last price. However, nobody knows the exact status of the next price whether it goes up or down or flat. So, hidden Markov model (HMM) is better fitted than MM. HMM is divided into discrete HMM (DHMM) and continuous HMM (CHMM). The only difference between DHMM and CHMM is in their representation of state probabilities. DHMM uses discrete probability density function and CHMM uses continuous probability density function such as Gaussian Mixture Model. KOSPI200 index values are real number and these follow a continuous probability density function, so CHMM is proper than DHMM for the KOSPI200 index. In this paper, we present an artificial intelligent trading system based on CHMM for the KOSPI200 index futures system traders. Traders have experienced on technical trading for the KOSPI200 index futures market ever since the introduction of the KOSPI200 index futures market. They have applied many strategies to make profit in trading the KOSPI200 index futures. Some strategies are based on technical indicators such as moving averages or stochastics, and others are based on candlestick patterns such as three outside up, three outside down, harami or doji star. We show a trading system of moving average cross strategy based on CHMM, and we compare it to a traditional algorithmic trading system. We set the parameter values of moving averages at common values used by market practitioners. Empirical results are presented to compare the simulation performance with the traditional algorithmic trading system using long-term daily KOSPI200 index data of more than 20 years. Our suggested trading system shows higher trading performance than naive system trading.

A Comparative Study on the Curriculum of Nursing Education in America and Korea (한.미 간호 교육과정의 비교 연구 -간호대학과정을 중심으로-)

  • 김정자
    • Journal of Korean Academy of Nursing
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    • v.7 no.2
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    • pp.60-82
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    • 1977
  • The purpose of this study is first, to analyse the present nursing education and the curriculum in Korea in view of the changes and the new tendency of nursing education and second, to compare our curriculum with that of America, where nursing activities are actively earring on and, third, to try to find out what we should reconsider and improve in our nursing education. The object of this study is the educational program and the curriculum from 1973 to 1976 by selecting each five from colleges and department of nursing in Korea and America. The results of the study were as fellows : . 1. The aim of nursing education puts impassion the role of leader, knowledge and technology of nursing, welfare of society and service of community in both the America and Korea. In Korea nursing is mainly restricted to the treatment of diseases, while in the America the items of the aim of nursing are mainly extended to the capacity for Self- realization of nurse, in Korea they are restricted to the treatment of diseases. 2. In Korea the rate of credit of the curriculum of nursing education is the highest in professional education, next in general education, next in supporting science and educational subject, while in America the rate of the credit is the highest in general education, next professional education and then supporting Science and educational subject isn′t included in the curriculum. 3. In both Korea and America the role of the animal credit allotment in general education, is the highest in the first year and the rate in supporting science is the highest in the second year. In Korea professional subjects are concentrated in the third year while in America there is a tendency that they are increasing in number in the grade order. 4. There is a tendency that the rate of the credit allotment of the main professional subjects in curriculum is higher in Korea than in America : that is, in Korea the rate of the allotment of the credit is the highest in medical - surgical nursing, next maternal - child nursing, next community - health nursing and the psychiatric nursing and there in a great difference in the rate of the allotment of each credit. While in America the rate of the allotment of the credit is the highest in community - health nursing, next in medical- surgical nursing, next in maternal - child nursing, and then in psychiatric nursing and there is little difference in the rate of tile allotment of each credit. 5. From general education, supporting science and professional education, they have considered the continuity and sequence in the structure of nursing curriculum of Korea and America. While in Korea we have partly made integration in tile content of the subjects. Most of the school in America, they have made integration in the content of subjects especially in all subjects, but in Korea we haven't made it in all subjects. 6. In the system and form of nursing education Problem solving method, Dialectical method and operational method are introduced in some America schools and in others there is a tendency that the whole nursing education has the system based on Preventive frame - work or Health -illness frame work ; while only one college has an attempt for Health - Illness continue in Korea. 7. In Korea nursing education, as the importance of health- nursing and team nursing, the aim which is also comparatively emphasized is about health management and service of collective community. The subject pertaining to the aim is the studies of community health nursing, which are more in number in America. 8. When we consider the association between the social, general aims ?f the nursing education and the formation of the curriculum in Korean nursing school the courses of study concerning "the role of leadership and cooperative personal relation": "nursing care for the group": dynamic nursing care": and "the system of the public health nursing associated with the understanding of the regional community" are insufficient as compared with those of America. Especially, the lack of the behavioral science including the nursing care connected with the care for the group, the basic science on the clinical and developmental psychology, anthropology in known to be a prominent issue.

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A Study on the Analysis and Efficiency of Police Budget (경찰의 예산분석 및 효율화 방안에 관한 연구)

  • Park, Jong-Seung;Kim, Chang-Yun
    • Korean Security Journal
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    • no.38
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    • pp.7-32
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    • 2014
  • This study is aimed to analyze problems of police budgetary execution and to suggest better ways for establishing effective budget implementation as well as legitimacy of securing budget in the field of police work. For this purpose, this paper analyzed the annual reports on police budgetary execution, from 2009 to 2012, conducted by National Assembly Budget Office. In result, most parts of the police budgetary execution were not satisfied with the audit standard, and especially in terms of management of budgetary execution, it showed 40% in inappropriateness. In addition, excessive and underestimate appropriation in the police budgetary execution, which happened frequently in other offices, was recorded on the second place. 10% of the amount of budget was executed for ordinance violence. Given results analyzed from each division, Transportation Division occupied 40% of the amount of related problems and all of types in the field did not meet the audit standard, thus it is required to manage budgetary execution effectively. In terms of Public Safety Division, the problem was related to budgetary allocation prior to execution, such as overlap in other works, excessive and underestimate appropriation, and inappropriate business plans. Director General for Planning and Coordination did not meet the standard of law system maintenance, Given the light of the result of analyzing programs, traffic safety and securing communication was the most problematic and support for police administration, crime prevention and protecting the disadvantaged, educating professional police officers, and establishment of policing infrastructure were required to be reformed in sequence. In order to resolve these problems, it is demanded to check budgetary execution and the process in business plans on a regular basis. Additionally, in case of using budget in inappropriate parts, tough penality including reduction of budget in related to the local police should be implemented to increase the importance of budgetary execution. Moreover, because of the fact that a part of problem of budgetary execution was originally caused by the budgetary allocation, it is advised to allocate police budget using the budget proposal of National Finance Act and Ministry of Strategy and Finance.

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Fate of Heavy Metals in Activated Sludge: Sorption of Heavy Metal ions by Nocardia amarae

  • Kim, Dong-wook
    • Proceedings of the Korean Environmental Sciences Society Conference
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    • 1998.10a
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    • pp.2-4
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    • 1998
  • Proliferation of Nocardia amarae cells in activated sludge has often been associated with the generation of nuisance foams. Despite intense research activities in recent years to examine the causes and control of Nocardia foaming in activated sludge, the foaming continued to persist throughout the activated sludge treatment plants in United States. In addition to causing various operational problems to treatment processes, the presence of Nocardia may have secondary effects on the fate of heavy metals that are not well known. For example, for treatment plants facing more stringent metal removal requirements, potential metal removal by Nocardia cells in foaming activated sludge would be a welcome secondary effect. In contrast, with new viosolid disposal regulations in place (Code o( Federal Regulation No. 503), higher concentration of metals in biosolids from foaming activated sludge could create management problems. The goal of this research was to investigate the metal sorption property of Nocardia amarae cells grown in batch reactors and in chemostat reactors. Specific surface area and metal sorption characteristics of N. amarae cells harvested at various growth stages were compared. Three metals examined in this study were copper, cadmium and nickel. Nocardia amarae strain (SRWTP isolate) used in this study was obtained from the University of California at Berkeley. The pure culture was grown in 4L batch reactor containing mineral salt medium with sodium acetate as the sole carbon source. In order to quantify the sorption of heavy metal ions to N amarae cell surfaces, cells from the batch reactor were harvested, washed, and suspended in 30mL centrifuge tubes. Metal sorption studies were conducted at pH 7.0 and ionlc strength of 10-2M. The sorption Isotherm showed that the cells harvested from the stationary and endogenous growth phase exhibited significantly higher metal sorption capacity than the cells from the exponential phase. The sequence of preferential uptake of metals by N. amarae cells was Cu>Cd>Ni. The specific surFace area of Nocardia cells was determined by a dye adsorption method. N.amarae cells growing at ewponential phase had significantly less specific surface area than that of stationary phase, indicating that the lower metal sorption capacity of Nocardia cells growing at exponential phase may be due to the lower specific surface area. The growth conditions of Nocardia cells in continuous culture affect their cell surface properties, thereby governing the adsorption capacity of heavy metal. The comparison of dye sorption isotherms for Nocardia cells growing at various growth rates revealed that the cell surface area increased with increasing sludge age, indicating that the cell surface area is highly dependent on the steady-state growth rate. The highest specific surface area of 199m21g was obtained from N.amarae cell harvested at 0.33 day-1 of growth rate. This result suggests that growth condition not only alters the structure of Nocardia cell wall but also affects the surface area, thus yielding more binding sites of metal removal. After reaching the steady-state condition at dilution rate, metal adsorption isotherms were used to determine the equilibrium distributions of metals between aqueous and Nocardia cell surfaces. The metal sorption capacity of Nocardia biomass harvested from 0.33 day-1 of growth rate was significantly higher than that of cells harvested from 0.5- and 1-day-1 operation, indicatng that N.amarae cells with a lower growth rate have higher sorpion capacity. This result was in close agreement with the trend observed from the batch study. To evaluate the effect of Nocardia cells on the metal binding capacity of activated sludge, specific surface area and metal sorption capacity of the mixture of Nocardia pure cultures and activated sludge biomass were determined by a series of batch experiments. The higher levels of Nocardia cells in the Nocardia-activated sludge samples resulted in the higher specific surface area, explaining the higher metal sorption sites by the mixed luquor samples containing greater amounts on Nocardia cells. The effect of Nocardia cells on the metal sorption capacity of activated sludge was evaluated by spiking an activated sludge sample with various amounts of pre culture Nocardia cells. The results of the Langmuir isotherm model fitted to the metal sorption by various mixtures of Nocardia and activated sludge indicated that the mixture containing higher Nocardia levels had higher metal adsorption capacity than the mixture containing lower Nocardia levels. At Nocardia levels above 100mg/g VSS, the metal sorption capacity of activate sludge increased proportionally with the amount of Noeardia cells present in the mixed liquor, indicating that the presence of Nocardia may increase the viosorption capacity of activated sludge.

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Effect of Soil Environment on Diversity and Population of Aerobic Soil Bacteria from Baekdudaegan Mountain Forests in Gyeongsangbuk-do, Korea (경상북도 산림지역의 토양 환경이 호기성 토양 세균의 다양성과 밀도에 미치는 영향)

  • Park, Chul Yeong;Lee, Sun Keun;Kim, Ji Hong;Lee, Sang Yong;Lee, Jong Kyu
    • Journal of Korean Society of Forest Science
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    • v.101 no.3
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    • pp.501-508
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    • 2012
  • This study was carried out to compare species diversity of soil bacteria from Baekdudaegan mountain forests (Bonghwa-gun, Mungyeong-si and Sangju-si) in Gyeongsangbuk-do and to analyze the effects of soil environments on diversity and population of soil bacteria. Soil bacteria were isolated from soil samples by streak plate method, and identified by DNA extaction and 16S rDNA sequence analyses. The population of soil bacteria from the soil samples of Bonghwa-gun was the highest with $5.1{\times}10^5cfu/g$, and followed by those from Mungyeong-si and Sangju-si with $1.9{\times}10^5cfu/g$ and $1.1{\times}10^5cfu/g$, respectively. The population of soil bacteria from surface layer soil was the highest, and then gradually decreased according to soil depth. The increase in population of soil bacteria from soil samples of different sites was correlated with the increase of the altitude of soil sampling site, depth of A horizon, liquid phase among three phases of soil, water content and bulk density of soil. Two hundreds and sixty eight bacterial colonies from Bonghwa-gun were classified into 10 species, 8 genera. One hundred and thirty four bacterial colonies from Mungyeong-si were classified into 15 species, 9 genera. Forty four bacterial colonies from Sangju-si were classified into 5 species, 2 genera. The dominant species (occupancy rate) from Bonghwa-gun and Mungyeong-si were Bacillus weihenstephanensis (36% and 40%, respectively), and Sangju-si was Bacillus cereus (39%). The relationships between soil environment and community structure of soil bacteria were analyzed statistically by using ecological indices. The diversity, evenness and dominance indices of soil bacteria were 6.30, 2.04 and 0.59 in Bonghwa-gun, 9.09, 2.94 and 0.51 in Mungyeong-si, and 4.55, 2.34 and 0.71 in Sangju-si, respectively. The diversity and evenness indices were increased by the increase of water content, drainage condition and gravel content of soil, while the dominance index was decreased.

Comparative Analysis of Signal Intensity and Apparent Diffusion Coefficient at Varying b-values in the Brain : Diffusion Weighted-Echo Planar Image ($T_2^*$ and FLAIR) Sequence (뇌의 확산강조 영상에서 b-value의 변화에 따른 신호강도, 현성확산계수에 관한 비교 분석 : 확산강조 에코평면영상($T_2^*$ 및 FLAIR)기법 중심으로)

  • Oh, Jong-Kap;Im, Jung-Yeol
    • Journal of radiological science and technology
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    • v.32 no.3
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    • pp.313-323
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    • 2009
  • Diffusion-weighted imaging (DWI) has been demonstrated to be a practical method for the diagnosis of various brain diseases such as acute infarction, brain tumor, and white matter disease. In this study, we used two techniques to examine the average signal intensity (SI) and apparent diffusion coefficient (ADC) of the brains of patients who ranged in age from 10 to 60 years. Our results indicated that the average SI was the highest in amygdala (as derived from DWI), whereas that in the cerebrospinal fluid was the lowest. The average ADC was the highest in the cerebrospinal fluid, whereas the lowest measurement was derived from the pons. The average SI and ADC were higher in $T_2^*$-DW-EPI than in FLAIR-DW-EPI. The higher the b-value, the smaller the average difference in both imaging techniques; the lower the b-value, the greater the average difference. Also, comparative analysis of the brains of patients who had experienced cerebral infarction showed no distinct lesion in the general MR image over time. However, there was a high SI in apparent weighted images. Analysis of other brain diseases (e.g., bleeding, acute, subacute, chronic infarction) indicated SI variance in accordance with characteristics of the two techniques. The higher the SI, the lower the ADC. Taken together, the value of SI and ADC in accordance with frequently occurring areas and various brain disease varies based on the b-value and imaging technique. Because they provide additional useful information in the diagnosis and treatment of patients with various brain diseases through signal recognition, the proper imaging technique and b-value are important for the detection and interpretation of subacute stroke and other brain diseases.

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Targeted Therapies and Radiation for the Treatment of Head and Neck Cancer (두경부 암의 표적 지향적 방사선 치료)

  • Kim, Gwi-Eon
    • Radiation Oncology Journal
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    • v.22 no.2
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    • pp.77-90
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    • 2004
  • Purpose: The purpose of this review Is to provide an update on novel radiation treatments for head and neck cancer Recent Findings: Despite the remarkable advances In chemotherapy and radiotherapy techniques, the management of advanced head and neck cancer remains challenging. Epidermal growth factor receptor (EGFR) Is an appealing target for novel therapies In head and neck cancer because not only EGFR activation stimulates many important signaling pathways associated with cancer development and progression, and importantly, resistance to radiation. Furthermore, EGFR overexpression Is known to be portended for a worse outcome in patients with advanced head and neck cancer. Two categories of compounds designed to abrogate EGFR signaling, such as monoclonal antibodies (Cetuxlmab) and tyrosine kinase inhibitors (ZD1839 and 051-774) have been assessed and have been most extensively studied In preclinical models and clinical trials. Additional TKIs In clinical trials include a reversible agent, Cl-1033, which blocks activation of all erbB receptors. Encouraging preclinical data for head and neck cancers resulted In rapid translation Into the clinic. Results from Initial clinical trials show rather surprisingly that only minority of patients benefited from EGFR inhibition as monotherapy or In combination with chemotherapy. In this review, we begin with a brief summary of erbB- mediated signal transduction. Subsequently, we present data on prognostic-predictive value of erbB receptor expression in HNC followed by preclinlcal and clinical data on the role of EGFR antagonists alone or in combination with radiation In the treatment of HNC. Finally, we discuss the emerging thoughts on resistance to EGFR biockade and efforts In the development of multiple-targeted therapy for combination with chemotherapy or radiation. Current challenges for investigators are to determine (1 ) who will benefit from targeted agents and which agents are most appropriate to combine with radiation and/or chemotherapy, (2) how to sequence these agents with radiation and/or cytotoxlc compounds, (3) reliable markers for patient selection and verification of effective blockade of signaling in vivo, and (4) mechanisms behind intrinsic or acquired resistance to targeted agents to facilitate rational development of multi-targeted therapy, Other molecuiar-targeted approaches In head and neck cancer were briefly described, Including angloenesis Inhibitors, farnesyl transferase inhibitors, cell cycle regulators, and gene therapy Summary: Novel targeted theraples are highly appealing in advanced head and neck cancer, and the most premising strategy to use them Is a matter of intense Investigation.

A STUDY ON THE DISTRIBUTION OF PARENTAL CONSULTATION ON THE WEBSITE OF KOREAN ACADEMY OF PEDIATRIC DENTISTRY (대한소아치과학회 홈페이지에 오른 진료상담 내용의 분석)

  • Oh, Young-Jun;Min, Yun-Kyung;Jung, Tae-Sung;Kim, Shin
    • Journal of the korean academy of Pediatric Dentistry
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    • v.29 no.3
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    • pp.439-443
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    • 2002
  • The purpose of this study was to analyze the parental consultation. Also, it was to investigate the tendency divided into different subjects. The subjects were 2142 questions on korean academy of pediatric dentistry homepage. The questions were categorized into 7 subjects, 37 subdivided subjects and children age. The results were as follows: 1. Age group was divided into $0{\sim}6months$, $7{\sim}12months$, $13{\sim}24months$, $25{\sim}36months$, $3{\sim}6years$, $7{\sim}12years$ 12years and over 13 years. $13{\sim}24months$ and $3{\sim}6years$ age group had the largest number of questions. 2. The subject were growth & development, development disturbance & oral disease, behavior management, operative & endodontic treatment, dentition & occlusal guidance, traumatic injury & surgery and etc. Development disturbance & oral disease had the largest number of questions. 3. In subdivided subjects, operative & endodontic treatment showed the most, followed by development & eruption of teeth, traumatic injury, cross-bite, tooth brushing methods in sequence. 4. In age group within subdivided subjects, the most frequent question was neonatal & natal tooth in $0{\sim}6months$, development & eruption of teeth in $7{\sim}12months$, $13{\sim}24months$, operative & endodontic treatment in $25{\sim}36months$, $3{\sim}6years$, time & method of orthodontics in $7{\sim}12years$ and operative & endodontic treatment in over 13years. 5. The questions about cross-bite, traumatic injury and soft tissue disease were distributed evenly in age group.

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A Topic Modeling-based Recommender System Considering Changes in User Preferences (고객 선호 변화를 고려한 토픽 모델링 기반 추천 시스템)

  • Kang, So Young;Kim, Jae Kyeong;Choi, Il Young;Kang, Chang Dong
    • Journal of Intelligence and Information Systems
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    • v.26 no.2
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    • pp.43-56
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    • 2020
  • Recommender systems help users make the best choice among various options. Especially, recommender systems play important roles in internet sites as digital information is generated innumerable every second. Many studies on recommender systems have focused on an accurate recommendation. However, there are some problems to overcome in order for the recommendation system to be commercially successful. First, there is a lack of transparency in the recommender system. That is, users cannot know why products are recommended. Second, the recommender system cannot immediately reflect changes in user preferences. That is, although the preference of the user's product changes over time, the recommender system must rebuild the model to reflect the user's preference. Therefore, in this study, we proposed a recommendation methodology using topic modeling and sequential association rule mining to solve these problems from review data. Product reviews provide useful information for recommendations because product reviews include not only rating of the product but also various contents such as user experiences and emotional state. So, reviews imply user preference for the product. So, topic modeling is useful for explaining why items are recommended to users. In addition, sequential association rule mining is useful for identifying changes in user preferences. The proposed methodology is largely divided into two phases. The first phase is to create user profile based on topic modeling. After extracting topics from user reviews on products, user profile on topics is created. The second phase is to recommend products using sequential rules that appear in buying behaviors of users as time passes. The buying behaviors are derived from a change in the topic of each user. A collaborative filtering-based recommendation system was developed as a benchmark system, and we compared the performance of the proposed methodology with that of the collaborative filtering-based recommendation system using Amazon's review dataset. As evaluation metrics, accuracy, recall, precision, and F1 were used. For topic modeling, collapsed Gibbs sampling was conducted. And we extracted 15 topics. Looking at the main topics, topic 1, top 3, topic 4, topic 7, topic 9, topic 13, topic 14 are related to "comedy shows", "high-teen drama series", "crime investigation drama", "horror theme", "British drama", "medical drama", "science fiction drama", respectively. As a result of comparative analysis, the proposed methodology outperformed the collaborative filtering-based recommendation system. From the results, we found that the time just prior to the recommendation was very important for inferring changes in user preference. Therefore, the proposed methodology not only can secure the transparency of the recommender system but also can reflect the user's preferences that change over time. However, the proposed methodology has some limitations. The proposed methodology cannot recommend product elaborately if the number of products included in the topic is large. In addition, the number of sequential patterns is small because the number of topics is too small. Therefore, future research needs to consider these limitations.