• Asian Pacific Journal of Cancer Prevention
• /
• v.13 no.8
• /
• pp.3617-3619
• /
• 2012

Background: The completeness of cancer registration is a major validity index of any reported cancer incidence. The present study aimed to evaluate the esophageal cancer incidence registered in the Tehran Metropolitan Area Cancer Registry. Materials and methods: The data on esophageal cancer abstracted from three sources of 1) pathology departments, 2) medical records, and 3) death certificates during 2003 till 2007 were utilized. The completeness of the data sources were evaluated using coverage (defined as the proportion of a community population with esophageal cancer identified by the source) and density (defined as the proportion of non-empty fields of the data by source). Results: A total 1,404 cases of esophageal cancer were reported for the duration of the study. Pathology provided 771, medical records 432, and death certificates 609. The coverage was 0.55 for pathology, 0.31 for medical records, and 0.43 for death certificates. The respective density values were 0.82, 0.96 and 0.98, respectively. Pathology (0.45) was the most complete source followed by medical records (0.42), and death certificates (0.29). Discussion: A low degree of completeness dictates putting more effort into case finding plus abstracting data more thoroughly.

• Journal of KIISE:Information Networking
• /
• v.30 no.3
• /
• pp.329-342
• /
• 2003

Most of the existing multicast routing protocols for ad-hoc networks do not take into account the efficiency of the protocol for the cases when there are large number of sources in the multicast group, resulting in either large overhead or poor data delivery ratio when the number of sources is large. In this paper, we propose a multicast routing protocol for ad-hoc networks, which particularly considers the scalability of the protocol in terms of the number of sources in the multicast groups. The proposed protocol designates a set of sources as the core sources. Each core source is a root of each tree that reaches all the destinations of the multicast group. The union of these trees constitutes the data delivery mesh, and each of the non-core sources finds the nearest core source in order to delegate its data delivery. For the efficient operation of the proposed protocol, it is important to have an appropriate number of core sources. Having too many of the core sources incurs excessive control and data packet overhead, whereas having too little of them results in a vulnerable and overloaded data delivery mesh. The data delivery mesh is optimally reconfigured through the periodic control message flooding from the core sources, whereas the connectivity of the mesh is maintained by a persistent local mesh recovery mechanism. The simulation results show that the proposed protocol achieves an efficient multicast communication with high data delivery ratio and low communication overhead compared with the other existing multicast routing protocols when there are multiple sources in the multicast group.

• Journal of The Korean Astronomical Society
• /
• v.21 no.2
• /
• pp.117-132
• /
• 1988

Multi-frequency polarization observations of Abell 695 are reported here. The brightest radio source 0838+325, which was previously classified as a wide angled head-tail radio source, is, in the present observations, resolved into two separable sources, a head-tail source 0838+325 AB and a diffuse one 0838+325C. The radio-tail shows high degree of linear polarization(${\sim}50$-25%) along the radio-tail, suggesting that the interaction with its surrounding intracluster medium (ICM) is not highly turbulent. With the present data, thermal particle densities at the locations of these sources are estimated to be n > $10^{-5}\;cm^{-3}$.

• International Journal of Human Ecology
• /
• v.11 no.2
• /
• pp.51-61
• /
• 2010

Using data from the 2007 SCF, this study examined the use of information source for investment decisions of elderly consumers. The results indicated that many elderly consumers (about 88%) involved savings /investment decisions. The elderly used 'Experts' (39.48%) as a major information source for their investment decisions, followed by 'Friends' (24.18%). The results of the multinomial logit analysis suggested that the perceived value, the cost for search, knowledge, risk and some of the demographic factors were significantly related to the choice of the information sources for investments by elderly consumers.

• Journal of Preventive Medicine and Public Health
• /
• v.57 no.4
• /
• pp.307-318
• /
• 2024

Objectives: Effective data collection and surveillance of epidemiological trends are essential in confronting the growing challenges associated with substance use (SU), especially in light of emerging trends and underreporting of cases. However, research and data are scarce regarding SU and substance use disorder (SUD) in Korea. Methods: We conducted a scoping review to identify data sources and surveillance methods used in SU research in Korea up to December 2023. This review was complemented by semi-structured consultations with experts in this area in Korea, whose feedback led to revisions of previously identified data sources and assessments. Results: Our review identified 32 publications conducting secondary analyses on existing data to examine the epidemiology of SU and SUD in Korea. Of these, 14 studies utilized clinical databases to explore the prescription patterns of addictive substances, particularly opioids. Eleven data sources showed promise for advancing SU research; however, they face substantial limitations, including a lack of available data, missing data, the absence of key variables, the exclusion of marginalized populations not captured within the clinical system, and complexities in matching individual-level data across time points and datasets. Conclusions: Current surveillance methods for SU in Korea face considerable challenges in accessibility, usability, and standardization. Moreover, existing data repositories may fail to capture information on populations not served by clinical or judicial systems. To systematically improve surveillance approaches, it is necessary to develop a robust and nationally representative survey, refine the use of existing clinical data, and ensure the availability of data on treatment facilities.

• Journal of Families and Better Life
• /
• v.14 no.4
• /
• pp.107-128
• /
• 1996

This study is conducted to examine elderly consumers' information needs according to information sources. And the relation with related variables purchasing problems of the elderly consumers and their needs according to information sources is investigated. The data was collected from 782 elderly consumers ages range from 55 to 74 and major findings are as follows: (1) Their needs according to information sources are relatively high and followed by neutral information source department store personnels and advertisements (2) The more esperiences they have and the more seriously they perceive their purchasing problems in a relatively poor conditon of a market the more information they want from department store personnels. (3) How many experiences they have and how much they perceive seriously in purchasing problems are the major intervening variables which have strong positve effects on the needs. The experiences show the strongest effects on the needs. The level of the percept on is strongly related to the needs and neutral information source is the major effect among the information sources.

• Proceedings of the KIEE Conference
• /
• 2004.07c
• /
• pp.1784-1786
• /
• 2004

PD(Partial Discharge) signal emitted from PD sources has their intrinsic features in the region of time and frequency. STFT(Short Time Fourier Transform) shows time-frequency distribution at the same time. 2-Dimensional matrices(33${\times}$77) from STFT for PD pulse signals are a good feature vectors and can be decreased in dimension by wavelet 2D data compression technique. Decreased feature vectors(13${\times}$24) were used as inputs of Back-propagation ANN(Artificial Neural Network) for discrimination of Multi-PD sources(air discharge sources(3), surface discharge(1)). They are a good feature vectors for discriminating Multi-PD sources.

• Journal of The Korean Astronomical Society
• /
• v.38 no.2
• /
• pp.141-144
• /
• 2005

Based on optical galaxy data, we executed a systematic search for galaxy clusters around the 15 steady unidentified EGRET GeV gamma-ray sources in high Galactic-latitude sky ([b] > $30^{\circ}$). We found a strong correlation with 3.7$\sigma$ level between close cluster pairs (merging cluster candidates) and the unidentified EGRET sources, though, in contrast, no correlation with single clusters. This result implies that merging clusters of galaxies are a possible candidate for the origin of high galactic-latitude, steady unidentified EGRET gamma-ray sources.

• The Transactions of the Korean Institute of Electrical Engineers C
• /
• v.54 no.7
• /
• pp.332-338
• /
• 2005

PD(Partial Discharge) signal emitted from PD sources has their intrinsic features in the region of time and frequency STFT(Short Time Fourier Transform) shows time-frequency distribution at the same time. 2-Dimensional matrices(33$\times$77) from STFT for PD pulse signals are a good feature vectors and can be decreased in dimension by wavelet 2D data compression technique. Decreased feature vectors(13$\times$24) were used as inputs of Back-propagation ANN(Artificial Neural Network) for discrimination of Multi-PD sources(air discharge sources(3), surface discharge(1)). They are a good feature vectors for discriminating Multi-PD sources in the air.

• Korean Journal of Human Ecology
• /
• v.13 no.2
• /
• pp.291-300
• /
• 2004

The purposes of this study were to research the clothing shopping orientations and the utilizations of information sources according to values of male consumer aged between the 20's and the 30's. The data were analyzed by factor analysis, one-way ANOVA, Duncan's multiple range test, x2- test, Pearson's correlation. The results of the study were as follows: 1. Male consumer's values were classified into 2 factors, and consisted of three groups. 2. There were significant differences among groups according to demographics variables. 3. Clothing shopping orientations were classified into 6 factors and information sources were classified into 3 factors. 4. There were relationships between male consumer's values, clothing shopping orientation, and utilization of information sources.