• Title/Summary/Keyword: BAE

Search Result 42,094, Processing Time 0.072 seconds

Preference of Elementary School Students Compared by Dietitians' Perception in School Lunch Program (학교급식 음료 선호도에 대한 초등학생과 영양사의 인식 비교)

  • Bae, Moon-Hee;Seo, Sun-Hee
    • Journal of the Korean Society of Food Science and Nutrition
    • /
    • v.36 no.8
    • /
    • pp.1083-1093
    • /
    • 2007
  • The purpose of this study was to investigate the difference between students' beverage preference and dietitians' perception in elementary school lunch program. This study was conducted in three phases: (1) questionnaire development and survey administration to elementary school students (2) survey administration to dietitians who were in charge of the elementary school food service, and (3) comparison of beverage preferences between elementary school students and dietitians. In phase I, 703 elementary school students in Seoul were surveyed from July 11 to July 19. In Phase II, 100 school food service dietitians in Seoul participated by mail survey from September 15 to October 30, 2006. Based on the results, elementary school students tended to show a neutral milk preference (mean=3.04), whereas dietitians perceived that elementary school students had lower milk preference (mean=2.67). Also dietitians perceived higher yogurt preference (mean=4.27) than the real elementary school students' preference (mean=4.02). T-test results showed the gender difference on milk and yogurt preference. Male students had higher milk preference (t=4.912, p<0.001) and yogurt preference (t=3.621, p<0.001) than female students. Elementary school students showed high fruit juice preference (mean=4.34); however, dietitians perceived lower fruit juice preference of students (mean=3.92). There was no gender difference on fruit juice preference. Though elementary school students had higher fruit juice preference, the frequency of fruit juice served in school lunch was quite low. Over half of the dietitians reported that they served fruit juice less than once a semester. The results of this study indicated the existence of distinctive difference between students' fruit juice preference and school lunch menu offerings.

The Early Experience with a Totally Laparoscopic Distal Gastrectomy (전(全)복강경하 원위부 위절제술의 초기 경험)

  • Kim Jin Jo;Song Gyo Young;Chin Hyung Min;Kim Wook;Jeon Hae Myoung;Park Cho Hyun;Park Seung Man;Lim Keun Woo;Park Woo Bae;Kim Seung Nam
    • Journal of Gastric Cancer
    • /
    • v.5 no.1
    • /
    • pp.16-22
    • /
    • 2005
  • Purpose: In Korea, the number of laparoscopy-assisted distal gastrectomies for early gastric cancer patients has been increasing lately. Although minimally invasive surgery is more beneficial, no reported case of a totally laparoscopic distal gastrectomy has been reported because of difficulty with intracorporeal anastomosis. This study attempts, through our experiences, to determine the feasibility of a totally laparoscopic distal gastrectomy using an intracorporeal gastroduodenostomy in treating early gastric carcinoma. Materials and Methods: We investigated surgical results and clinicopatholgic characteristics of eight(8) patients with an early gastric carcinoma who underwent a totally laparoscopic distal gastrectomy at the Department of Surgery, Our Lady of Mercy Hospital, The Catholic University of Korea, between June 2004 and September 2004. The intracorporeal gastroduodenostomy was performed with a delta-shaped ananstomosis by using only laparoscopic linear staplers (Endocutter 45mm; Ethicon Endosurgery, OH, USA). Results: The operative time was $369.4\pm62.5$ minutes (range $275\∼465$ minutes), and the anastomotic time was 45.1\pm14.4$ minutes (range $32\∼70$ minutes). The anastomotic time was shortened as surgical experience was gained. The number of laparoscopic linear staplers for an operation was $7.1\pm0.6$. The number of lymph nodes harvested was $31.9\pm13.1$. There was 1 case of transfusion and no case of conversion to an open procedure. The time to the first flatus was 2.8$\pm$0.5 days, and the time to the first food intake was $4.1\pm0.8$ days. There were no early postoperative complications, and the postoperative hospital stay was $10.0\pm3.9$ days. Conclusion: A totally laparoscopic distal gastrectomy using an intracorporeal gastroduodenostomy with a delta-shaped anastomosis is technically feasible and can maximize the benefit of laparoscopic surgery for early gastric cancer.

  • PDF

Twitter Issue Tracking System by Topic Modeling Techniques (토픽 모델링을 이용한 트위터 이슈 트래킹 시스템)

  • Bae, Jung-Hwan;Han, Nam-Gi;Song, Min
    • Journal of Intelligence and Information Systems
    • /
    • v.20 no.2
    • /
    • pp.109-122
    • /
    • 2014
  • People are nowadays creating a tremendous amount of data on Social Network Service (SNS). In particular, the incorporation of SNS into mobile devices has resulted in massive amounts of data generation, thereby greatly influencing society. This is an unmatched phenomenon in history, and now we live in the Age of Big Data. SNS Data is defined as a condition of Big Data where the amount of data (volume), data input and output speeds (velocity), and the variety of data types (variety) are satisfied. If someone intends to discover the trend of an issue in SNS Big Data, this information can be used as a new important source for the creation of new values because this information covers the whole of society. In this study, a Twitter Issue Tracking System (TITS) is designed and established to meet the needs of analyzing SNS Big Data. TITS extracts issues from Twitter texts and visualizes them on the web. The proposed system provides the following four functions: (1) Provide the topic keyword set that corresponds to daily ranking; (2) Visualize the daily time series graph of a topic for the duration of a month; (3) Provide the importance of a topic through a treemap based on the score system and frequency; (4) Visualize the daily time-series graph of keywords by searching the keyword; The present study analyzes the Big Data generated by SNS in real time. SNS Big Data analysis requires various natural language processing techniques, including the removal of stop words, and noun extraction for processing various unrefined forms of unstructured data. In addition, such analysis requires the latest big data technology to process rapidly a large amount of real-time data, such as the Hadoop distributed system or NoSQL, which is an alternative to relational database. We built TITS based on Hadoop to optimize the processing of big data because Hadoop is designed to scale up from single node computing to thousands of machines. Furthermore, we use MongoDB, which is classified as a NoSQL database. In addition, MongoDB is an open source platform, document-oriented database that provides high performance, high availability, and automatic scaling. Unlike existing relational database, there are no schema or tables with MongoDB, and its most important goal is that of data accessibility and data processing performance. In the Age of Big Data, the visualization of Big Data is more attractive to the Big Data community because it helps analysts to examine such data easily and clearly. Therefore, TITS uses the d3.js library as a visualization tool. This library is designed for the purpose of creating Data Driven Documents that bind document object model (DOM) and any data; the interaction between data is easy and useful for managing real-time data stream with smooth animation. In addition, TITS uses a bootstrap made of pre-configured plug-in style sheets and JavaScript libraries to build a web system. The TITS Graphical User Interface (GUI) is designed using these libraries, and it is capable of detecting issues on Twitter in an easy and intuitive manner. The proposed work demonstrates the superiority of our issue detection techniques by matching detected issues with corresponding online news articles. The contributions of the present study are threefold. First, we suggest an alternative approach to real-time big data analysis, which has become an extremely important issue. Second, we apply a topic modeling technique that is used in various research areas, including Library and Information Science (LIS). Based on this, we can confirm the utility of storytelling and time series analysis. Third, we develop a web-based system, and make the system available for the real-time discovery of topics. The present study conducted experiments with nearly 150 million tweets in Korea during March 2013.

Image Watermarking for Copyright Protection of Images on Shopping Mall (쇼핑몰 이미지 저작권보호를 위한 영상 워터마킹)

  • Bae, Kyoung-Yul
    • Journal of Intelligence and Information Systems
    • /
    • v.19 no.4
    • /
    • pp.147-157
    • /
    • 2013
  • With the advent of the digital environment that can be accessed anytime, anywhere with the introduction of high-speed network, the free distribution and use of digital content were made possible. Ironically this environment is raising a variety of copyright infringement, and product images used in the online shopping mall are pirated frequently. There are many controversial issues whether shopping mall images are creative works or not. According to Supreme Court's decision in 2001, to ad pictures taken with ham products is simply a clone of the appearance of objects to deliver nothing but the decision was not only creative expression. But for the photographer's losses recognized in the advertising photo shoot takes the typical cost was estimated damages. According to Seoul District Court precedents in 2003, if there are the photographer's personality and creativity in the selection of the subject, the composition of the set, the direction and amount of light control, set the angle of the camera, shutter speed, shutter chance, other shooting methods for capturing, developing and printing process, the works should be protected by copyright law by the Court's sentence. In order to receive copyright protection of the shopping mall images by the law, it is simply not to convey the status of the product, the photographer's personality and creativity can be recognized that it requires effort. Accordingly, the cost of making the mall image increases, and the necessity for copyright protection becomes higher. The product images of the online shopping mall have a very unique configuration unlike the general pictures such as portraits and landscape photos and, therefore, the general image watermarking technique can not satisfy the requirements of the image watermarking. Because background of product images commonly used in shopping malls is white or black, or gray scale (gradient) color, it is difficult to utilize the space to embed a watermark and the area is very sensitive even a slight change. In this paper, the characteristics of images used in shopping malls are analyzed and a watermarking technology which is suitable to the shopping mall images is proposed. The proposed image watermarking technology divide a product image into smaller blocks, and the corresponding blocks are transformed by DCT (Discrete Cosine Transform), and then the watermark information was inserted into images using quantization of DCT coefficients. Because uniform treatment of the DCT coefficients for quantization cause visual blocking artifacts, the proposed algorithm used weighted mask which quantizes finely the coefficients located block boundaries and coarsely the coefficients located center area of the block. This mask improves subjective visual quality as well as the objective quality of the images. In addition, in order to improve the safety of the algorithm, the blocks which is embedded the watermark are randomly selected and the turbo code is used to reduce the BER when extracting the watermark. The PSNR(Peak Signal to Noise Ratio) of the shopping mall image watermarked by the proposed algorithm is 40.7~48.5[dB] and BER(Bit Error Rate) after JPEG with QF = 70 is 0. This means the watermarked image is high quality and the algorithm is robust to JPEG compression that is used generally at the online shopping malls. Also, for 40% change in size and 40 degrees of rotation, the BER is 0. In general, the shopping malls are used compressed images with QF which is higher than 90. Because the pirated image is used to replicate from original image, the proposed algorithm can identify the copyright infringement in the most cases. As shown the experimental results, the proposed algorithm is suitable to the shopping mall images with simple background. However, the future study should be carried out to enhance the robustness of the proposed algorithm because the robustness loss is occurred after mask process.

Study on Health Behavior of Hypertensive Patients and Compliance for Treatment of Antihypertensive Medication (고혈압 환자들의 순응도와 건강행태의 관계)

  • Kim, Joo-Yeon;Lee, Dong-Bae;Cho, Young-Chae;Lee, Sok-Goo;Chang, Seong-Sil;Kwon, Yun-Hyung;Lee, Tae-Yong
    • Journal of agricultural medicine and community health
    • /
    • v.25 no.1
    • /
    • pp.29-49
    • /
    • 2000
  • Objectives: To estimate the prevalence rate of hypertension, the changes of health behavior, and compliance for the drug treatment after diagnosed as hypertension. Methods: 7,030 persons who live in Cheonan City of Chungnam Province were selected by the cluster sampling method, and 5,372 persons were surveyed by questionnaire and health examination. This data is analyzed by Chi-square test on each variable. Results: 49.8%- of men and 38.8%- of women had been diagnosed as hypertension, and the prevalence rate of hypertension was significantly increased with aging in both gender. The prevalence rate tended to decrease in highly educated women group. Unemployed persons or obese persons showed relatively higher prevalence rate. The prevalence rate of hypertension increased in groups with higher total cholesterol levels over 240 mg/dl, and groups with glucose level over 200 mg/dl. 53.1%- of male patients and 66.6%- of female patients showed compliance for antihypertensive treatment. Compliance for treatment was higher in aged group or lower educated group in both gender. Among men, proportion of compliant subjects was higher in unemployed group(49.3%-), and lower in labor or primary industry than the others but among women, there was not any significant difference. And men with compliance for treatment had higher monthly income than the others, but women did not show any. Conclusion : This population had a high prevalence rate of hypertension which may lead to cardiovascular disease. Therefore health education programs and distribution of information must be emphasized in order to increase compliance to treatment and encourage the change of health behavior to promote health.

  • PDF

The Utility of Immunological Markers and Pulmonary Function Test in the Early Diagnosis of Pulmonary Involvement in the Patients with Rheumatoid Arthritis (류마티스 관절염환자에서 폐침범의 진단에 있어서 면역학적 지표와 폐기능 검사의 유용성)

  • Lee, Dong-Suk;Lee, Chang-Beam;Koh, Hee-Kwan;Moon, Doo-Seop;Lee, Jae-Young;Lee, Kyung-Sang;Yang, Suck-Chul;Yoon, Ho-Joo;Bae, Sang-Cheol;Shin, Dong-Ho;Kim, Seong-Yoon;Park, Sung-Soo;Lee, Jung-Hee
    • Tuberculosis and Respiratory Diseases
    • /
    • v.42 no.6
    • /
    • pp.878-887
    • /
    • 1995
  • Background: It is reported that frequency of pulmonary involvement in the patients with rheumatoid arthritis reaches 10 to 50% and pulmonary involvement is a principal cause of death. As immunology and radiology has developed, interest for the early diagnosis of pulmonary involvement is increasing. Method: Among the patients at Hanyang University Hospital from March, 1990 to July, 1995, we compared the 29 patients having pulmonary involvement with the 18 patients controls in clinical and chest high resolution computed tomography(HRCT) findings by immunological markers and findings of pulmonary function test. We sought useful markers for early diagnosis of pulmonary involvement with noninvasive investigations. Results: The ratio of males to females was 14 : 15 in the group of pulmonary involvement, and all of the 18 patients were females in the control group. Smoking history was 31%(9/29) in the former group and none in the latter group. Rheumatoid factor(RF) was positive in 95.5%(28/29) of the pulmonary involvement group and in 100%(18/18) of the control group(p=0.12). Antiperinuclear factor(APF) showed a significant difference: 86.9%(20/23, average value: 2.0) was positive in the pulmonary involvement group and 50%(8/16, average value: 1.1) in the control group(p=0.04). Antinuclear antibody(ANA) was positive in 60.7%(17/28) of the pulmonary involvement group and in 72.2%(13/18) of the control group(p=0.33). Cryoglobulin also showed a significant difference: 72%(18/25) in the pulmonary involvement group was positive and 56.2%(9/16) in the control group was positive(p=0.02). Bony erosion was positive in 61.5%(16/26) of the pulmonary involvement group and in 77.7%(14/18) of the control group(p=0.8). On the pulmonary function test, the average value of alveolar volume corrected diffusion capacity and residual volume in the pulmonary involvement group and in the control group were 1.07mmol/rnin/KPa(predicted value: 64.2%), 1.32L(predicted value: 70%) and 1.44mmol/min/KPa, 3.75L(predicted value: 86.6%), respectively(p=0.003, p=0.004), showing a significant difference. Conclusion: APF or cryoglobulin on the serological test, the measurement of residual volume and alveolar volume corrected diffusion capacity may be used as effective markers in the diagnosis of pulmonary involvement of the patients with rheumatoid arthritis.

  • PDF

Changes in Biochemical Components of Several Tissues of the Hard Clam, Meretrix petechialis, in Relation to Gonad Developmental Phases (말백합, Meretrix petechialis의 생식소 발달단계에 따른 일부 조직의 생화학적 성분 변화)

  • Kim, Yong-Min;Park, Kwan-Ha;Chung, Ee-Yung;Kim, Jong-Bae;Lee, Chang-Hoon
    • The Korean Journal of Malacology
    • /
    • v.22 no.2
    • /
    • pp.125-134
    • /
    • 2006
  • We investigated the reproductive cycle of the hard clam, Meretrix petechialis with its gonadal development by histological observations. The seasonal changes in biochemical component of the adductor muscle, visceral mass, foot muscle and mantle of the clam were studied by biochemical analysis, from January to December, 2002. The reproductive cycle of this species can be divided into five successive stages: early stage (January to March), late active stage (February to May), ripe stage (April to August), partially spawned stage (July to August) and spent/inactive stage (September to January). Total protein content in the visceral mass was over two times higher than that in the adductor muscle. Monthly changes of total protein content in the adductor muscle were not statistically significant (ANOVA, p = 0.071), while the changes in the visceral mass were significant (p < 0.001). Total protein content in visceral mass was higher during the early active, late active, and ripe stages (from January to May), while the lowest in July. Glycogen content in the adductor muscle was higher than that in the visceral mass. Monthly changes in glycogen contents were statistically significant in both adductor muscle (F = 237.2, p < 0.001) and the visceral mass (F = 64.04, p < 0.001). Glycogen content in the adductor muscle was the highest in the ripe stage (April). Its content was lower in the partially spawned and the spent/inactive stages (June-September). Glycogen contents in the visceral mass were relatively lower until the early active stage, while the highest in the late active stage. RNA content was higher in visceral mass than that in the adductor muscle. Monthly changes in RNA contents were significant in both adductor muscle (F = 195.2, p < 0.001) and visceral mass (F = 78.85, p < 0.001). RNA content in the adductor muscle was high in the early active stage (January-February), and then it decreased rapidly in the late active stage (March-April), thereafter, slightly increased during the partially spawned stage (June-July). RNA content in the visceral mass reached a maximum during the ripe stage (May), and then it decreased rapidly during the partially-spawned stage (June-July). There was significant positive correlation in total protein contents between adductor muscle and visceral mass (r = 0.715, p = 0.020). However, there was no correlation between adductor muscle and visceral mass in glycogen (p = 0.550), while a negative correlation was found between the adductor muscle and visceral mass in RNA (p = 0.518) contents. Especially, changes in RNA content showed a negative correlation between the adductor muscle tissue and visceral mass. Therefore, these results suggest that the nutrient content of the adductor muscle, visceral muscle and foot muscle changed in response to gonadal energy needs.

  • PDF

Changes in blood pressure and determinants of blood pressure level and change in Korean adolescents (성장기 청소년의 혈압변화와 결정요인)

  • Suh, Il;Nam, Chung-Mo;Jee, Sun-Ha;Kim, Suk-Il;Kim, Young-Ok;Kim, Sung-Soon;Shim, Won-Heum;Kim, Chun-Bae;Lee, Kang-Hee;Ha, Jong-Won;Kang, Hyung-Gon;Oh, Kyung-Won
    • Journal of Preventive Medicine and Public Health
    • /
    • v.30 no.2 s.57
    • /
    • pp.308-326
    • /
    • 1997
  • Many studies have led to the notion that essential hypertension in adults is the result of a process that starts early in life: investigation of blood pressure(BP) in children and adolescents can therefore contribute to knowledge of the etiology of the condition. A unique longitudinal study on BP in Korea, known as Kangwha Children's Blood Pressure(KCBP) Study was initiated in 1986 to investigate changes in BP in children. This study is a part of the KCBP study. The purposes of this study are to show changes in BP and to determine factors affecting to BP level and change in Korean adolescents during age period 12 to 16 years. A total of 710 students(335 males, 375 females) who were in the first grade at junior high school(12 years old) in 1992 in Kangwha County, Korea have been followed to measure BP and related factors(anthropometric, serologic and dietary factors) annually up to 1996. A total of 562 students(242 males, 320 females) completed all five annual examinations. The main results are as follows: 1. For males, mean systolic and diastolic BP at age 12 and 16 years old were 108.7 mmHg and 118.1 mmHg(systolic), and 69.5 mmHg and 73.4 mmHg(diastolic), respectively. BP level was the highest when students were at 15 years old. For females, mean systolic and diastolic BP at age 12 and 16 years were 114.4 mmHg and 113.5 mmHg(systolic) and 75.2 mmHg and 72.1 mmHg(diastolic), respectively. BP level reached the highest point when they were 13-14 years old. 2. Anthropometric variables(height, weight and body mass index, etc) increased constantly during the study period for males. However, the rate of increase was decreased for females after age 15 years. Serum total cholesterol decreased and triglyceride increased according to age for males, but they did not show any significant trend fer females. Total fat intake increased at age 16 years compared with that at age 14 years. Compositions of carbohydrate, protein and fat among total energy intake were 66.2:12.0:19.4, 64.1:12.1:21.8 at age 14 and 16 years, respectively. 3. Most of anthropometric measures, especially, height, body mass index(BMI) and triceps skinfold thickness showed a significant correlation with BP level in both sexes. When BMI was adjusted, serum total cholesterol showed a significant negative correlation with systolic BP at age 12 years in males, but at age 14 years the direction of correlation changed to positive. In females serum total cholesterol was negatively correlated with diastolic BP at age 15 and 16 years. Triglyceride and creatinine showed positive correlation with systolic and diastolic BP in males, but they did not show any correlation in females. There was no consistent findings between nutrient intake and BP level. However, protein intake correlated positively with diastolic BP level in males. 4. Blood pressure change was positively associated with changes in BMI and serum total cholesterol in both sexes. Change in creatinine was associated with BP change positively in males and negatively in females. Students whose sodium intake was high showed higher systolic and diastolic BP in males, and students whose total fat intake was high maintained lower level of BP in females. The major determinants on BP change was BMI in both sexes.

  • PDF

Serial Changes of Serum Thyroid-Stimulating Hormone after Total Thyroidectomy or Withdrawal of Suppressive Thyroxine Therapy in Patients with Differentiated Thyroid Cancer (분화성 갑상선 암 환자에서 갑상선 전절제술후 또는 갑상선 호르몬 억제 요법 중단에 따른 갑상선 자극호르몬의 변화)

  • Bae, Jin-Ho;Lee, Jae-Tae;Seo, Ji-Hyoung;Jeong, Shin-Young;Jung, Jin-Hyang;Park, Ho-Yong;Kim, Jung-Guk;Ahn, Byeong-Cheol;Sohn, Jin-Ho;Kim, Bo-Wan;Park, June-Sik;Lee, Kyu-Bo
    • The Korean Journal of Nuclear Medicine
    • /
    • v.38 no.6
    • /
    • pp.516-521
    • /
    • 2004
  • Background: Radioactive iodine (RAI) therapy and whole-body scanning are the fundamentals of treatment and follow-up of patients with differentiated thyroid cancer. It is generally accepted that a Thyroid-Stimulating Hormone (TSH) level of at least 30 ${\mu}U/ml$ is a prerequisite for the effective use of RAI, and that it requires 4-6 weeks of off-thyroxine to attain these levels. Because thyroxine withdrawal and the consequent hypothyroidism are often poorly tolerated, and occasionally might be hazardous, it is important to be certain that these assumptions are correct. We have measured serial changes in serum TSH after total thyroidectomy or withdrawl of thyroxine in patients with thyroid cancer. Subjects and Methods: Serum TSH levels were measured weekly after thyroidectomy in 10 patients (group A) and after the discontinuation of thyroxine in 12 patients (group B). Symptoms and signs of hypothyroidism were also evaluated weekly by modified Billewicz diagnostic index. Results: By the second week, 78% of group A patients and 17% of group B patients had serum TSH levels ${\geq}30{\mu}U/ml$. By the third week, 89% of group A patients and 90% of group B patients had serum TSH levels ${\geq}30{\mu}U/ml$. By the fourth week, all patients in two groups achieved target TSH levels and there were no overt hypothyroidism. Conclusion: in all patients, serum TSH elevated to the target concentration (${\geq}30{\mu}U/ml$) within 4 weeks without significant manifestation of hypothyroidism. The schedule of RAI administration could be adjusted to fit the needs and circumstances of individual patients with a shorter preparation period than the conventional.

Analysis of Twitter for 2012 South Korea Presidential Election by Text Mining Techniques (텍스트 마이닝을 이용한 2012년 한국대선 관련 트위터 분석)

  • Bae, Jung-Hwan;Son, Ji-Eun;Song, Min
    • Journal of Intelligence and Information Systems
    • /
    • v.19 no.3
    • /
    • pp.141-156
    • /
    • 2013
  • Social media is a representative form of the Web 2.0 that shapes the change of a user's information behavior by allowing users to produce their own contents without any expert skills. In particular, as a new communication medium, it has a profound impact on the social change by enabling users to communicate with the masses and acquaintances their opinions and thoughts. Social media data plays a significant role in an emerging Big Data arena. A variety of research areas such as social network analysis, opinion mining, and so on, therefore, have paid attention to discover meaningful information from vast amounts of data buried in social media. Social media has recently become main foci to the field of Information Retrieval and Text Mining because not only it produces massive unstructured textual data in real-time but also it serves as an influential channel for opinion leading. But most of the previous studies have adopted broad-brush and limited approaches. These approaches have made it difficult to find and analyze new information. To overcome these limitations, we developed a real-time Twitter trend mining system to capture the trend in real-time processing big stream datasets of Twitter. The system offers the functions of term co-occurrence retrieval, visualization of Twitter users by query, similarity calculation between two users, topic modeling to keep track of changes of topical trend, and mention-based user network analysis. In addition, we conducted a case study on the 2012 Korean presidential election. We collected 1,737,969 tweets which contain candidates' name and election on Twitter in Korea (http://www.twitter.com/) for one month in 2012 (October 1 to October 31). The case study shows that the system provides useful information and detects the trend of society effectively. The system also retrieves the list of terms co-occurred by given query terms. We compare the results of term co-occurrence retrieval by giving influential candidates' name, 'Geun Hae Park', 'Jae In Moon', and 'Chul Su Ahn' as query terms. General terms which are related to presidential election such as 'Presidential Election', 'Proclamation in Support', Public opinion poll' appear frequently. Also the results show specific terms that differentiate each candidate's feature such as 'Park Jung Hee' and 'Yuk Young Su' from the query 'Guen Hae Park', 'a single candidacy agreement' and 'Time of voting extension' from the query 'Jae In Moon' and 'a single candidacy agreement' and 'down contract' from the query 'Chul Su Ahn'. Our system not only extracts 10 topics along with related terms but also shows topics' dynamic changes over time by employing the multinomial Latent Dirichlet Allocation technique. Each topic can show one of two types of patterns-Rising tendency and Falling tendencydepending on the change of the probability distribution. To determine the relationship between topic trends in Twitter and social issues in the real world, we compare topic trends with related news articles. We are able to identify that Twitter can track the issue faster than the other media, newspapers. The user network in Twitter is different from those of other social media because of distinctive characteristics of making relationships in Twitter. Twitter users can make their relationships by exchanging mentions. We visualize and analyze mention based networks of 136,754 users. We put three candidates' name as query terms-Geun Hae Park', 'Jae In Moon', and 'Chul Su Ahn'. The results show that Twitter users mention all candidates' name regardless of their political tendencies. This case study discloses that Twitter could be an effective tool to detect and predict dynamic changes of social issues, and mention-based user networks could show different aspects of user behavior as a unique network that is uniquely found in Twitter.