• Tuberculosis and Respiratory Diseases
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• v.49 no.3
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• pp.323-331
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• 2000

Purpose: Brain metastases are present in approximately 10-16% of small cell lung cancer patients at diagnosis. Brain metastasis is an important clinical problem associated with increasing the survival rate, with a cumulative incidence of up to 80% in patients surviving 2 years. Prophylactic cranial irradiation(PCI) reduces the incidence of brain matastasis and may prolong survival in patients with limited small-cell lung cancer who achieved complete remission. This study was performed to analyze the incidence of brain metastasis, survival and clinical aspects after PCI in patients with limited small-cell lung cancer who achieved complete remission. Methods : Between 1989 and 1999, forty-two patients with limited small-cell lung cancer who achived achieved complete remission after therapy were enrolled into this study retrospectively. All patients received etoposide and cisplatin(VPP) alternating with cytoxan, adriamycin, and vincristine(CAV) every 3 weeks for at least 6 cycles initially. All patients received thoracic radiotherapy: concurrent(38.1%) and sequential(61.9%). All patients received late PCI. Results : Most patients(88.1%) were men, and the median age was 58 years. The median follow-up duration was 18.1 months. During the follow-up period, 57.1% of the patients developed relapse. The most frequent site of relapse was chest(35.7%), followed by brain(14.3%), liver(11.9%), adrenal gland(44%), and bone(2.2%). With the Kaplan-Meier method, the average disease-free interval was 1,090 days(median 305 days). The average time to development of brain relapse after PCI and other sites relapse(except brain) were 2,548 days and 1,395 days(median 460 days), respectively. The average overall survival was 1,233 days(median 634 days, 21.1 months), and 2-year survival rates was 41.7%. The average overall survival in the relapse group was 642 days(median 489 days) and in the no relapse group was 2,622 days(p<0.001). The average overall survival in the brain relapse group was 928 days(median 822 days) and in the no brain relapse group was 1,308 days(median 634 days)(p=0.772). In most patients(85.7%), relapse(except brain) or systemic disease was the usual cause of death. Brain matastasis was the cause of death in 14.3% of the cases. Conclusions : We may conclude that PCI reduces and delays brain metastasis in patients with limited small cell lung cancer who achieved complete remission. We found decreased survival in relapse group but, no significant survival difference was noted according to brain matastasis. And relapse(except brain) or systemic disease was the usual cause of death. In order to increase survival, new treatment strategies for control methods for relapse and systemic disease are required.

• The Journal of the Korean bone and joint tumor society
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• v.11 no.1
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• pp.54-61
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• 2005

Purpose: The granulocytic sarcoma which developed in leukemic patients are quite rare and it will have bad prognosis, but it's tumor pathogenesis and also their treatment are not yet established. Through this study we have tried to know their clinical course, prognosis and their end result of recent treatment. Material and Methods: Total 20 patients of granulocytic sarcoma which were developed in total 2,197 leukemic patients from April, 1998 to September, 2004 were treated at the leukemic center and the orthopaedic department of St. Mary's hospital, Catholic University of Korea, and followed them for 1~78 months(average 18 months). Results: Total 20 cases of granulocytic sarcoma was found in 14 cases of total 1,331 acute myelocytic leukemic patients(AML), 4 cases of total 744 of chronic myelocytic leukemic patients(CML), and only one case in total 122 of acute biphenotype of leukemia. And so their occurrence rate in leukmic patients are actually 0.91%, total 20 cases of granulocytic sarcoma in total 2,197 leukemic patients at same period. Their ages are average 28.3 years(4~52 years), and male are predominant(13 cases) than female(7 cases). Single involvement was found in 11 cases but multiple lesions are in 9 cases, and spine, brain, extremities, chest, and pelvic bone are involved in frequency. The granulocytic sarcoma was developed in various stages of the leukemia, ie, 8 cases in complete remission of leukemia, and 12 cases in the treatment process of AML. The pathohistologic evaluation of granulocytic sarcoma was done in 6 cases which was developed in their extremities, and confirmed numerous immature myeloblasts and lymphocytes mixed. The treatment of these granulocytic sarcoma was mainly limited for the treatment of leukemia by Glivac and massive steroid therapy(19cases) and also combined with the bone marrow transplantation(13 cases), but radiation therapy with average 3,500 rads in 15 cases out of total 20 sarcomas was also done, and followed them for average 17.5 months after development of granulocytic sarcomas. Finally their prognosis was so bad that 12 patients(60%) out of total 20 granulocytic sarcoma were dead in 6.5 months after sarcoma developed and we found the granulocytic sarcoma was more fatal if they are developed during the process of CML(mortality: 100%(4/4cases). Conclusion: The prognosis of granulocytic sarcomas in leukemic patients are quite fatal, and much more studies for their pathogenesis and ways of treatment should be performed continuously.

• 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.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 1993.06a
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• pp.1051-1054
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• 1993

The International Atomic Energy Agency's Statute in Article III.A.5 allows it“to establish and administer safeguards designed to ensure that special fissionable and other materials, services, equipment, facilities and information made available by the Agency or at its request or under its supervision or control are not used in such a way as to further any military purpose; and to apply safeguards, at the request of the parties, to any bilateral or multilateral arrangement, or at the request of a State, to any of that State's activities in the field of atomic energy”. Safeguards are essentially a technical means of verifying the fulfilment of political obligations undertaken by States and given a legal force in international agreements relating to the peaceful uses of nuclear energy. The main political objectives are: to assure the international community that States are complying with their non-proliferation and other peaceful undertakings; and to deter (a) the diversion of afeguarded nuclear materials to the production of nuclear explosives or for military purposes and (b) the misuse of safeguarded facilities with the aim of producing unsafeguarded nuclear material. It is clear that no international safeguards system can physically prevent diversion. The IAEA safeguards system is basically a verification measure designed to provide assurance in those cases in which diversion has not occurred. Verification is accomplished by two basic means: material accountancy and containment and surveillance measures. Nuclear material accountancy is the fundamental IAEA safeguards mechanism, while containment and surveillance serve as important complementary measures. Material accountancy refers to a collection of measurements and other determinations which enable the State and the Agency to maintain a current picture of the location and movement of nuclear material into and out of material balance areas, i. e. areas where all material entering or leaving is measurab e. A containment measure is one that is designed by taking advantage of structural characteristics, such as containers, tanks or pipes, etc. To establish the physical integrity of an area or item by preventing the undetected movement of nuclear material or equipment. Such measures involve the application of tamper-indicating or surveillance devices. Surveillance refers to both human and instrumental observation aimed at indicating the movement of nuclear material. The verification process consists of three over-lapping elements: (a) Provision by the State of information such as - design information describing nuclear installations; - accounting reports listing nuclear material inventories, receipts and shipments; - documents amplifying and clarifying reports, as applicable; - notification of international transfers of nuclear material. (b) Collection by the IAEA of information through inspection activities such as - verification of design information - examination of records and repo ts - measurement of nuclear material - examination of containment and surveillance measures - follow-up activities in case of unusual findings. (c) Evaluation of the information provided by the State and of that collected by inspectors to determine the completeness, accuracy and validity of the information provided by the State and to resolve any anomalies and discrepancies. To design an effective verification system, one must identify possible ways and means by which nuclear material could be diverted from peaceful uses, including means to conceal such diversions. These theoretical ways and means, which have become known as diversion strategies, are used as one of the basic inputs for the development of safeguards procedures, equipment and instrumentation. For analysis of implementation strategy purposes, it is assumed that non-compliance cannot be excluded a priori and that consequently there is a low but non-zero probability that a diversion could be attempted in all safeguards ituations. An important element of diversion strategies is the identification of various possible diversion paths; the amount, type and location of nuclear material involved, the physical route and conversion of the material that may take place, rate of removal and concealment methods, as appropriate. With regard to the physical route and conversion of nuclear material the following main categories may be considered: - unreported removal of nuclear material from an installation or during transit - unreported introduction of nuclear material into an installation - unreported transfer of nuclear material from one material balance area to another - unreported production of nuclear material, e. g. enrichment of uranium or production of plutonium - undeclared uses of the material within the installation. With respect to the amount of nuclear material that might be diverted in a given time (the diversion rate), the continuum between the following two limiting cases is cons dered: - one significant quantity or more in a short time, often known as abrupt diversion; and - one significant quantity or more per year, for example, by accumulation of smaller amounts each time to add up to a significant quantity over a period of one year, often called protracted diversion. Concealment methods may include: - restriction of access of inspectors - falsification of records, reports and other material balance areas - replacement of nuclear material, e. g. use of dummy objects - falsification of measurements or of their evaluation - interference with IAEA installed equipment.As a result of diversion and its concealment or other actions, anomalies will occur. All reasonable diversion routes, scenarios/strategies and concealment methods have to be taken into account in designing safeguards implementation strategies so as to provide sufficient opportunities for the IAEA to observe such anomalies. The safeguards approach for each facility will make a different use of these procedures, equipment and instrumentation according to the various diversion strategies which could be applicable to that facility and according to the detection and inspection goals which are applied. Postulated pathways sets of scenarios comprise those elements of diversion strategies which might be carried out at a facility or across a State's fuel cycle with declared or undeclared activities. All such factors, however, contain a degree of fuzziness that need a human judgment to make the ultimate conclusion that all material is being used for peaceful purposes. Safeguards has been traditionally based on verification of declared material and facilities using material accountancy as a fundamental measure. The strength of material accountancy is based on the fact that it allows to detect any diversion independent of the diversion route taken. Material accountancy detects a diversion after it actually happened and thus is powerless to physically prevent it and can only deter by the risk of early detection any contemplation by State authorities to carry out a diversion. Recently the IAEA has been faced with new challenges. To deal with these, various measures are being reconsidered to strengthen the safeguards system such as enhanced assessment of the completeness of the State's initial declaration of nuclear material and installations under its jurisdiction enhanced monitoring and analysis of open information and analysis of open information that may indicate inconsistencies with the State's safeguards obligations. Precise information vital for such enhanced assessments and analyses is normally not available or, if available, difficult and expensive collection of information would be necessary. Above all, realistic appraisal of truth needs sound human judgment.

• Journal of Chest Surgery
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• v.38 no.2 s.247
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• pp.157-163
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• 2005

Background: Clinical outcomes of esophageal cancer have not been satisfactory in spite of the development of surgical skills and protocols of adjuvant therapy. We analyzed the results of corrective surgical patients for esophageal cancer from January 1992 to July 2002. Material and Method: Among 129 patients with esophageal cancer, this study was performed in 68 patients who received corrective surgery. The ratio of sex was 59 : 9 (male : female) and mean age was $61.07\pm7.36$ years old. Chief complaints of this patients were dysphagia, epigastric pain and weight loss, etc. The locations of esophageal cancer were 4 in upper esophagus, 36 in middle, 20 in lower, 8 in esophagogastric junction. 60 patients had squamous cell cancer and 7 had adenocarcinoma, and 1 had malignant melanoma. Five patients had neoadjuvant chemotherapy. Result: The postoperative stage I, IIA, IIB, III, IV patients were 7, 25, 12, 17 and 7, respectively. The conduit for replacement of esophagus were stomach (62 patients) and colon (6 patients). The neck anastomosis was performed in 28 patients and intrathoracic anastomosis in 40 patients. The technique of anastomosis were hand sewing method (44 patients) and stapling method (24 patients). One of the early complications was anastomosis leakage (3 patients) which had only radiologic leakage that recovered spontaneously. The anastomosis technique had no correlation with postoperative leakage, which stapling method (2 patients) and hand sewing method (1 patient). There were 3 respiratory failures, 6 pneumonia, 1 fulminant hepatitis, 1 bleeding and 1 sepsis. The 2 early postoperative deaths were fulminant hepatitis and sepsis. Among 68 patients, 23 patients had postoperative adjuvant therapy and 55 paitents were followed up. The follow up period was $23.73\pm22.18$ months ($1\~76$ month). There were 5 patients in stage I, 21 in stage 2A, 9 in stage IIB, 15 in stage III and 5 in stage IV. The 1, 3, 5 year survival rates of the patients who could be followed up completely was $58.43\pm6.5\%,\;35.48\pm7.5\%\;and\;18.81\pm7.7\%$, respectively. Statistical analysis showed that long-term survival difference was associated with a stage, T stage, and N stage (p<0.05) but not associated with histology, sex, anastomosis location, tumor location, and pre and postoperative adjuvant therapy. Conclusion: The early diagnosis, aggressive operative resection, and adequate postoperative treatment may have contributed to the observed increase in survival for esophageal cancer patients.

• Journal of Chest Surgery
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• v.40 no.1 s.270
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• pp.45-51
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• 2007

Background: Although echocardiography is usually used for quantitative assessment of left ventricular function, the recently developed 16-slice multidetector computed tomography (MDCT) is not only capable of evaluating the coronary arteries but also left ventricular function. Therefore, the objective of our study was to compare the values of left ventricular function quantified by MDCT to those by echocardiography for evaluation of its regards to clinical applications. Material and Method: From 49 patients who underwent MDCT in our hospital from November 1, 2003 to January 31, 2005, we enrolled 20 patients who underwent echocardiography during the same period for this study. Left ventricular end-diastolic volume index (LVEDVI), left ventricular end-systolic volume index (LVESVI), stroke volume index (SVI), left ventricular mass index (LVMI), and ejection fraction (EF) were analyzed. Result: Average LVEDVI ($80.86{\pm}34.69mL$ for MDCT vs $60.23{\pm}29.06mL$ for Echocardiography, p<0.01), average LVESVI ($37.96{\pm}24.52mL$ for MDCT vs $25.68{\pm}16.57mL$ for Echocardiography, p<0.01), average SVI ($42.90{\pm}15.86mL$ for MDCT vs $34.54{\pm}17.94mL$ for Echocardiography, p<0.01), average LVMI ($72.14{\pm}25.35mL$ for MDCT vs $130.35{\pm}53.10mL$ for Echocardiography, p<0.01), and average EF ($55.63{\pm}12.91mL$ for MOCT vs $59.95{\pm}12.75ml$ for Echocardiography, p<0.05) showed significant difference between both groups. Average LVEDVI, average LVESVI, and average SVI were higher in MDCT, and average LVMI and average EF were higher in echocardiogram. Comparing correlation for each parameters between both groups, LVEDVI $(r^2=0.74,\;p<0.0001)$, LVESVI $(r^2=0.69,\;p<0.0001)$ and SVI $(r^2=0.55,\;p<0.0001)$ showed high relevance, LVMI $(r^2=0.84,\;p<0.0001)$ showed very high relevance, and $EF (r^2=0.45,\;p=0.0002)$ showed relatively high relevance. Conclusion: Quantitative assessment of left ventricular volume and function using 16-slice MDCT showed high relevance compared with echocardiography, therefore may be a feasible assessment method. However, because the average of each parameters showed significant difference, the absolute values between both studies may not be appropriate for clinical applications. Furthermore, considering the future development of MDCT, we expect to be able to easily evaluate the assessment of coronary artery stenosis along with left ventricular function in coronary artery disease patients.

• Radiation Oncology Journal
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• v.23 no.2
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• pp.61-70
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• 2005

Purpose: Uterine cervix cancer is one of the most prevalent women cancer in Korea. We analysed published papers in Korea with comparing Patterns of Care Study (PCS) articles of United States and Japan for the purpose of developing and processing Korean PCS. Materials and Methods: We searched PCS related foreign-produced papers in the PCS homepage (212 articles and abstracts) and from the Pub Med to find Structure and Process of the PCS. To compare their study with Korean papers, we used the internet site 'Korean Pub Med' to search 99 articles regarding uterine cervix cancer and radiation therapy. We analysed Korean paper by comparing them with selected PCS papers regarding Structure, Process and Outcome and compared their items between the period of before 1980's and 1990's. Results: Evaluable papers were 28 from United States, 10 from the Japan and 73 from the Korea which treated cervix PCS items. PCS papers for United States and Japan commonly stratified into $3\~4$ categories on the bases of the scales characteristics of the facilities, numbers of the patients, doctors, Researchers restricted eligible patients strictly. For the process of the study, they analysed factors regarding pretreatment staging in chronological order, treatment related factors, factors in addition to FIGO staging and treatment machine. Papers in United States dealt with racial characteristics, socioeconomic characteristics of the patients, tumor size (6), and bilaterality of parametrial or pelvic side wail invasion (5), whereas papers from Japan treated of the tumor markers. The common trend in the process of staging work-up was decreased use of lymphangiogram, barium enema and increased use of CT and MRI over the times. The recent subject from the Korean papers dealt with concurrent chemoradiotherapy (9 papers), treatment duration (4), tumor markers (B) and unconventional fractionation. Conclusion: By comparing papers among 3 nations, we collected items for Korean uterine cervix cancer PCS. By consensus meeting and close communication, survey items for cervix cancer PCS were developed to measure structure, process and outcome of the radiation treatment of the cervix cancer. Subsequent future research will focus on the use of brachytherapy and its impact on outcome including complications. These finding and future PCS studies will direct the development of educational programs aimed at correcting identified deficits in care.

• Journal of Intelligence and Information Systems
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• v.22 no.2
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• pp.57-79
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• 2016

It is a rising trend that the number of users using one of the social media channels, the Social Network Service, so called the SNS, is getting increased. As per to this social trend, more companies have interest in this networking platform and start to invest their funds in it. It has received much attention as a tool spreading and expanding the message that a company wants to deliver to its customers and has been recognized as an important channel in terms of the relationship marketing with them. The environment of media that is radically changing these days makes possible for companies to approach their customers in various ways. Particularly, the social network service, which has been developed rapidly, provides the environment that customers can freely talk about products. For companies, it also works as a channel that gives customized information to customers. To succeed in the online environment, companies need to not only build the relationship between companies and customers but focus on the relationship between customers as well. In response to the online environment with the continuous development of technology, companies have tirelessly made the novel marketing strategy. Especially, as the one-to-one marketing to customers become available, it is more important for companies to maintain the relationship marketing with their customers. Among many SNS, Facebook, which many companies use as a communication channel, provides a fan page service for each company that supports its business. Facebook fan page is the platform that the event, information and announcement can be shared with customers using texts, videos, and pictures. Companies open their own fan pages in order to inform their companies and businesses. Such page functions as the websites of companies and has a characteristic of their brand communities such as blogs as well. As Facebook has become the major communication medium with customers, companies recognize its importance as the effective marketing channel, but they still need to investigate their business performances by using Facebook. Although there are infinite potentials in Facebook fan page that even has a function as a community between users, which other platforms do not, it is incomplete to regard companies' Facebook fan pages as communities and analyze them. In this study, it explores the relationship among customers through the network of the Facebook fan page users. The previous studies on a company's Facebook fan page were focused on finding out the effective operational direction by analyzing the use state of the company. However, in this study, it draws out the structural variable of the network, which customer committment can be measured by applying the social network analysis methodology and investigates the influence of the structural characteristics of network on the business performance of companies in an empirical way. Through each company's Facebook fan page, the network of users who engaged in the communication with each company is exploited and it is the one-mode undirected binary network that respectively regards users and the relationship of them in terms of their marketing activities as the node and link. In this network, it draws out the structural variable of network that can explain the customer commitment, who pressed "like," made comments and shared the Facebook marketing message, of each company by calculating density, global clustering coefficient, mean geodesic distance, diameter. By exploiting companies' historical performance such as net income and Tobin's Q indicator as the result variables, this study investigates influence on companies' business performances. For this purpose, it collects the network data on the subjects of 54 companies among KOSPI-listed companies, which have posted more than 100 articles on their Facebook fan pages during the data collection period. Then it draws out the network indicator of each company. The indicator related to companies' performances is calculated, based on the posted value on DART website of the Financial Supervisory Service. From the academic perspective, this study suggests a new approach through the social network analysis methodology to researchers who attempt to study the business-purpose utilization of the social media channel. From the practical perspective, this study proposes the more substantive marketing performance measurements to companies performing marketing activities through the social media and it is expected that it will bring a foundation of establishing smart business strategies by using the network indicators.

• Journal of Intelligence and Information Systems
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• v.24 no.4
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• pp.67-83
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• 2018

The Korean film industry with significant increase every year exceeded the number of cumulative audiences of 200 million people in 2013 finally. However, starting from 2015 the Korean film industry entered a period of low growth and experienced a negative growth after all in 2016. To overcome such difficulty, stakeholders like production company, distribution company, multiplex have attempted to maximize the market returns using strategies of predicting change of market and of responding to such market change immediately. Since a film is classified as one of experiential products, it is not easy to predict a box office record and the initial number of audiences before the film is released. And also, the number of audiences fluctuates with a variety of factors after the film is released. So, the production company and distribution company try to be guaranteed the number of screens at the opining time of a newly released by multiplex chains. However, the multiplex chains tend to open the screening schedule during only a week and then determine the number of screening of the forthcoming week based on the box office record and the evaluation of audiences. Many previous researches have conducted to deal with the prediction of box office records of films. In the early stage, the researches attempted to identify factors affecting the box office record. And nowadays, many studies have tried to apply various analytic techniques to the factors identified previously in order to improve the accuracy of prediction and to explain the effect of each factor instead of identifying new factors affecting the box office record. However, most of previous researches have limitations in that they used the total number of audiences from the opening to the end as a target variable, and this makes it difficult to predict and respond to the demand of market which changes dynamically. Therefore, the purpose of this study is to predict the weekly number of audiences of a newly released film so that the stakeholder can flexibly and elastically respond to the change of the number of audiences in the film. To that end, we considered the factors used in the previous studies affecting box office and developed new factors not used in previous studies such as the order of opening of movies, dynamics of sales. Along with the comprehensive factors, we used the machine learning method such as Random Forest, Multi Layer Perception, Support Vector Machine, and Naive Bays, to predict the number of cumulative visitors from the first week after a film release to the third week. At the point of the first and the second week, we predicted the cumulative number of visitors of the forthcoming week for a released film. And at the point of the third week, we predict the total number of visitors of the film. In addition, we predicted the total number of cumulative visitors also at the point of the both first week and second week using the same factors. As a result, we found the accuracy of predicting the number of visitors at the forthcoming week was higher than that of predicting the total number of them in all of three weeks, and also the accuracy of the Random Forest was the highest among the machine learning methods we used. This study has implications in that this study 1) considered various factors comprehensively which affect the box office record and merely addressed by other previous researches such as the weekly rating of audiences after release, the weekly rank of the film after release, and the weekly sales share after release, and 2) tried to predict and respond to the demand of market which changes dynamically by suggesting models which predicts the weekly number of audiences of newly released films so that the stakeholders can flexibly and elastically respond to the change of the number of audiences in the film.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.24 no.2
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• pp.267-281
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• 2019

Energetic mesoscale eddies in the East Sea (ES) associated with strong mesoscale variability impacting circulation and environments were statistically characterized by analyzing satellite altimeter data collected during 1993-2017 and in-situ data obtained from four cruises conducted between 2015 and 2017. A total of 1,008 mesoscale eddies were detected, tracked, and identified and then classified into 27 groups characterized by mean lifetime (L, day), amplitude (H, m), radius (R, km), intensity per unit area (EI, $cm^2/s^2/km^2$), ellipticity (e), eddy kinetic energy (EKE, TJ), available potential energy (APE, TJ), and direction of movement. The center, boundary, and amplitude of mesoscale eddies identified from satellite altimeter data were compared to those from the in-situ observational data for the four cases, yielding uncertainties in the center position of 2-10 km, boundary position of 10-20 km, and amplitude of 0.6-5.9 cm. The mean L, H, R, EI, e, EKE, and APE of the ES mesoscale eddies during the total period are $95{\pm}104$ days, $3.5{\pm}1.5cm$, $39{\pm}6km$, $0.023{\pm}0.017cm^2/s^2/km^2$, $0.72{\pm}0.07$, $23{\pm}21TJ$, and $588{\pm}250TJ$, respectively. The ES mesoscale eddies tend to move following the mean surface current rather than propagating westward. The southern groups (south of the subpolar front) have a longer L, larger H, R, and higher EKE, APE; and stronger EI than those of the northern groups and tend to move a longer distance following surface currents. There are exceptions to the average characteristics, such as the quasi-stationary groups (the Wonsan Warm, Wonsan Cold, Western Japan Basin Warm, and Northern Subpolar Frontal Cold Eddy groups) and short-lived groups with a relatively larger H, higher EKE, and APE and stronger EI (the Yamato Coastal Warm, Central Yamato Warm, and Eastern Japan Basin Coastal Warm eddy groups). Small eddies in the northern ES hardly resolved using the satellite altimetry data only, were not identified here and discussed with potential over-estimations of the mean L, H, R, EI, EKE, and APE. This study suggests that the ES mesoscale eddies 1) include newly identified groups such as the Hokkaido and the Yamato Rise Warm Eddies in addition to relatively well-known groups (e.g., the Ulleung Warm and the Dok Cold Eddies); 2) have a shorter L; smaller H, R, and lower EKE; and stronger EI and higher APE than those of the global ocean, and move following surface currents rather than propagating westward; and 3) show large spatial inhomogeneity among groups.