• The Korean Journal of Nuclear Medicine Technology
• /
• v.13 no.3
• /
• pp.76-80
• /
• 2009

Purpose: The uptake of $^{99m}Tc$-MIBI increases in the parathyroid adenoma, hyperplasia, and carcinoma. The purpose of this study is to evaluate and compare the results of the biopsy with quantitative analysis results in the localized parathyroid lesions (adenoma, hyperplasia, and carcinoma). Materials and Methods: From April 2002 to January 2009, double-phase $^{99m}Tc$-MIBI parathyroid scan (early 15 min, delayed 2 hrs) was performed after injection of 750 MBq of $^{99m}Tc$-MIBI in 27 diagnosed parathyroid patients (adenoma:15, hyperplasia:4, carcinoma:8). For quantitative analysis, early, delayed lesion to non-lesion ratios (L/NLs), washout rate (%, WR) and vertical axis were calculated. Results: In early images, lesion to non-lesion ratios were $1.53{\pm}0.41$ (adenoma), $1.38{\pm}0.27$ (hyperplasia) and $1.45{\pm}0.64$ (carcinoma). In delayed images, lesion to non-lesion ratios were $1.56{\pm}0.43$ (adenoma), $1.33{\pm}0.10$ (hyperplasia), $1.83{\pm}0.79$ (carcinoma). In vertical axis, the sizes were $2.11{\pm}0.67$ (adenoma), $2.23{\pm}0.75$ (hyperplasia) and $2.20{\pm}0.97$ (carcinoma). There was no statistical difference between lesion to non-lesion ratios and the size of vertical axis (p>0.05). However, washout rates were $31.59{\pm}13.97$ (adenoma), $37.8{\pm}5.69$ (hyperplasia), $17.73{\pm}11.02$ (carcinoma). As a result, there was a significant difference statistically between and that of carcinoma (p<0.05, p=0.028 by Kruskal-willis statistic, Dunn's Multiple comparison test SPSS Ver 12.0). Conclusions: There was no statistical difference between the lesion to non-lesion ratios and the size of vertical axis. However, there was a significant difference statistically between WR of hyperplasia and that of carcinoma.

• The Korean Journal of Nuclear Medicine Technology
• /
• v.13 no.3
• /
• pp.132-136
• /
• 2009

Purpose: WHO(world health organization) announced the FRAX Tool(fracture risk assessment) of new software in the beginning of 2008. FRAX Tool was considered various risk factor, being different from existing fracture risk. In this study, we wanted to know the fracture risk of following the changing of the risk factor of fracture. Materials and Methods: A total of 50 women aged 50~60 were studied. We measured BMD at the part of femur neck which was based on the age, weight, height of individual with GE, Lunar-prodigy. The control group is fracture risk without considering fracture risk factor. The experimental group is previous fracture, parent fracture, current smoking, glucocorticoid, rheumatoid arthritis, secondary osteoporosis, alcohol. if each items makes one 'existence', others are all 'nothing'. and the results produced major osteoporotic region and hip fracture risk in 10-years. Statistics used t-test of SPSS 12.0. Results: The average rate of increment of major osteoporotic region between control group and experimental group, previous fracture-74% increase, parent fracture-96% increase, current smoking-2% increase, glucocorticoid-61% increase, rheumatoid arthritis-29% increase, alcohol-20% increase, secondary osteoporosis-0.18% decrease. The average rate of increment of hip region between control group and experimental group, previous fracture-84% increase, parent fracture-5% increase, current smoking-72% increase, glucocorticoid-84% increase, rheumatoid arthritis-40% increase, alcohol-52% increase, secondary osteoporosis-1.69% decrease. Conclusions: Each fracture risk factor has different rate of increment between major osteoporotic and hip region while in occasion of the second osteoporosis it has little relation because of low P-value. We could know that a contribution of the risk factor is different between major osteoporotic and hip region.

• The Korean Journal of Nuclear Medicine Technology
• /
• v.13 no.3
• /
• pp.3-9
• /
• 2009

Purpose: It is well-known that stress-induced stunning and reversible perfusion defect have impact on ejection fraction (EF) when performing myocardial perfusion SPECT. Due to these reasons, gated SPECT is recommended at stress and rest studies. And there was many experiments to analyze between Stress and Rest EF by using $^{99m}Tc$-MIBI. The aim of this study is to analyze between stress EF and rest EF at myocardial perfusion SPECT by using $^{201}Tl$ and define possible predictors of EF variability. Materials and Methods: From 2008 June to 2009 February, we analyzed 144 patients undergoing $^{201}Tl$ gated myocardial perfusion SPECT in ASAN medical center. To analyze the data, we use QGS (Quantitative gated SPECT) software, and derived End-systolic volume (ESV), End-diastolic volume (EDV), EF from the result. In this study, we comparatively analyzed stress/rest EF correlation based on stress/rest EF, EDV, ESV and reversibility of myocardial perfusion defect by using paired t-test, Bland-Altman analysis. Results: Mached pairs of stress EF and rest EF demonstrated excellent correlation (r=0.92) with no statistically significant difference (p=0.11). Bland-Altman analysis demonstrated a mean ${\Delta}EF$ was 0.52% (95% confidential interval[CI], -1.17~0.12%). No statistically significant difference between a mean ${\Delta}EF$ and hypothetic mean of 0 (${\Delta}EF$=0) (p=0.10). In the correlation of ${\Delta}EF$ according to stress/rest EDV and ESV, except rest ESV of <28mL (p<0.05), there was no statistically significant difference. In the correlation of ${\Delta}EF$ according to reversibility of perfusion defect, patients with reversible perfusion defect has statistically significant difference of ${\Delta}EF$ (p<0.05). ${\Delta}EF$ of stress/rest EF showed no statistically significant difference except 55% of rest EF (p<0.05). Conclusion: Like studies with $^{99m}Tc$-MIBI, there was generally no statistically significant difference between stress and rest EF in this study results. However a stress EF of <55%, a rest ESV of <28mL and patients with reversible perfusion defect showed statistically significant difference in ${\Delta}EF$. If performing $^{201}T$ myocardial perfusion SPECT to patients with abnormal cardiac function or reversible perfusion defect, consider this study results and apply it. We expect this study results could be useful predictors of ${\Delta}EF$ variability.

• Journal of Astronomy and Space Sciences
• /
• v.23 no.4
• /
• pp.355-372
• /
• 2006

Mission opportunities and trajectory characteristics for the future Korean Mars mission have designed and analyzed using KSIV-III(Korea Space Launch Vehicle-III). Korea's first space center, 'NARO space center' is selected as a launch site. For launch opportunities, year 2033 is investigated under considering the date of space center's completion with KSLV series development status. Optimal magnitude of various maneuvers, Trans Mars Injection (TMI) maneuver, Trajectory Correction Maneuver (TCM), Mars Orbit Insertion (MOI) maneuver and Orbit Trim Maneuver(OTM), which are required during the every Mars mission phases are computed with the formulation of nonlinear optimization problems using NPSOL software. Finally, mass budgets for upper stage (launcher for KSIV-III and spacecraft are derived using various optimized maneuver magnitudes. For results, daily launch window from NARO space center for successful Korean Mars mission is avaliable for next 27 minutes starting from Apr. 16. 2033. 12:17:26 (UTC). Maximum spacecraft gross mass which can delivered to Mars is about 206kg, with propellant mass of 109kg and structure mass of 97kg, when on board spacecraft thruster's Isp is assumed to have 290 sec. For upper stage, having structure ratio of 0.15 and Isp value of 280 sec, gross mass is about 1293kg with propellant mass of 1099kg and structure mass of 194kg. However, including 10% margins to computed optimal maneuver values, spacecraft gross mass is reduced to about 148kg with upper stage's mass of 1352kg. This work will give various insights, requiring performances to developing of KSIV-III and spacecraft design for future Korean Mars missions.

• Journal of Applied Tourism Food and Beverage Management and Research
• /
• v.16 no.2
• /
• pp.175-199
• /
• 2005

Family Restaurant is a service business of a kind. The role of service operator is to improve a sales of service goods through maximizing the service value with customer satisfaction at the moment of MOT(moment of truth). Family Restaurant come to the great growth on the face of it. In future, it will place emphasis more and more on not hardware but software including service quality. The purpose of this study, therefore, is to research the effect on service quality of the job satisfaction of Family Restaurant's service staff. Data was collected from the employee who are working at Family Restaurant located in Taegu. The empirical research has been done over 50days from 1April, 2004 to 20May, 2004. In conclusion of empirical analysis, 4 hypotheses were significant among 7 hypotheses suggested in this study. The research showed as follows : First, the organic trait among the effect factor of job satisfaction perceived by Family Restaurant service staff showed positive influence on job satisfaction. Second, the personal trait among the effect factor of job satisfaction perceived by Family Restaurant service staff showed positive influence on service quality. Third, the official trait among the effect factor of job satisfaction perceived by Family Restaurant service staff showed negative influence on job satisfaction. Fourth, the organic trait among the effect factor of job satisfaction perceived by Family Restaurant service staff showed positive influence on service quality. Fifth, the personal trait among the effect factor of job satisfaction perceived by Family Restaurant service staff showed negative influence on service quality. Sixth, the organic trait among the effect factor of job satisfaction perceived by Family Restaurant service staff showed negative influence on service quality. Seventh, the job satisfaction of Family Restaurant service staff showed positive influence on service quality. Besides, the critical points of this study are as follows; First, we designated the subject of research to the employee of Family Restaurant only. Second, multi-situations(time, holiday) which can happen as service was offered, wasn't concerned. Third, as service quality was estimated by general service quality, the research in future should subdivide service quality more. I, finally, applied the pervious researches on job satisfaction and service quality in the employee of Family Restaurant. To extend more this research model in future, the variables like customer satisfaction should be added.

• Journal of Intelligence and Information Systems
• /
• v.17 no.1
• /
• pp.127-138
• /
• 2011

The core service of most research portal sites is providing relevant research papers to various researchers that match their research interests. This kind of service may only be effective and easy to use when a user can provide correct and concrete information about a paper such as the title, authors, and keywords. However, unfortunately, most users of this service are not acquainted with concrete bibliographic information. It implies that most users inevitably experience repeated trial and error attempts of keyword-based search. Especially, retrieving a relevant research paper is more difficult when a user is novice in the research domain and does not know appropriate keywords. In this case, a user should perform iterative searches as follows : i) perform an initial search with an arbitrary keyword, ii) acquire related keywords from the retrieved papers, and iii) perform another search again with the acquired keywords. This usage pattern implies that the level of service quality and user satisfaction of a portal site are strongly affected by the level of keyword management and searching mechanism. To overcome this kind of inefficiency, some leading research portal sites adopt the association rule mining-based keyword recommendation service that is similar to the product recommendation of online shopping malls. However, keyword recommendation only based on association analysis has limitation that it can show only a simple and direct relationship between two keywords. In other words, the association analysis itself is unable to present the complex relationships among many keywords in some adjacent research areas. To overcome this limitation, we propose the hybrid approach for establishing association network among keywords used in research papers. The keyword association network can be established by the following phases : i) a set of keywords specified in a certain paper are regarded as co-purchased items, ii) perform association analysis for the keywords and extract frequent patterns of keywords that satisfy predefined thresholds of confidence, support, and lift, and iii) schematize the frequent keyword patterns as a network to show the core keywords of each research area and connecting keywords among two or more research areas. To estimate the practical application of our approach, we performed a simple experiment with 600 keywords. The keywords are extracted from 131 research papers published in five prominent Korean journals in 2009. In the experiment, we used the SAS Enterprise Miner for association analysis and the R software for social network analysis. As the final outcome, we presented a network diagram and a cluster dendrogram for the keyword association network. We summarized the results in Section 4 of this paper. The main contribution of our proposed approach can be found in the following aspects : i) the keyword network can provide an initial roadmap of a research area to researchers who are novice in the domain, ii) a researcher can grasp the distribution of many keywords neighboring to a certain keyword, and iii) researchers can get some idea for converging different research areas by observing connecting keywords in the keyword association network. Further studies should include the following. First, the current version of our approach does not implement a standard meta-dictionary. For practical use, homonyms, synonyms, and multilingual problems should be resolved with a standard meta-dictionary. Additionally, more clear guidelines for clustering research areas and defining core and connecting keywords should be provided. Finally, intensive experiments not only on Korean research papers but also on international papers should be performed in further studies.

• Journal of Intelligence and Information Systems
• /
• v.20 no.4
• /
• pp.107-120
• /
• 2014

This study proposes a novel recommender system using the structural hole analysis to reflect qualitative and emotional information in recommendation process. Although collaborative filtering (CF) is known as the most popular recommendation algorithm, it has some limitations including scalability and sparsity problems. The scalability problem arises when the volume of users and items become quite large. It means that CF cannot scale up due to large computation time for finding neighbors from the user-item matrix as the number of users and items increases in real-world e-commerce sites. Sparsity is a common problem of most recommender systems due to the fact that users generally evaluate only a small portion of the whole items. In addition, the cold-start problem is the special case of the sparsity problem when users or items newly added to the system with no ratings at all. When the user's preference evaluation data is sparse, two users or items are unlikely to have common ratings, and finally, CF will predict ratings using a very limited number of similar users. Moreover, it may produces biased recommendations because similarity weights may be estimated using only a small portion of rating data. In this study, we suggest a novel limitation of the conventional CF. The limitation is that CF does not consider qualitative and emotional information about users in the recommendation process because it only utilizes user's preference scores of the user-item matrix. To address this novel limitation, this study proposes cluster-indexing CF model with the structural hole analysis for recommendations. In general, the structural hole means a location which connects two separate actors without any redundant connections in the network. The actor who occupies the structural hole can easily access to non-redundant, various and fresh information. Therefore, the actor who occupies the structural hole may be a important person in the focal network and he or she may be the representative person in the focal subgroup in the network. Thus, his or her characteristics may represent the general characteristics of the users in the focal subgroup. In this sense, we can distinguish friends and strangers of the focal user utilizing the structural hole analysis. This study uses the structural hole analysis to select structural holes in subgroups as an initial seeds for a cluster analysis. First, we gather data about users' preference ratings for items and their social network information. For gathering research data, we develop a data collection system. Then, we perform structural hole analysis and find structural holes of social network. Next, we use these structural holes as cluster centroids for the clustering algorithm. Finally, this study makes recommendations using CF within user's cluster, and compare the recommendation performances of comparative models. For implementing experiments of the proposed model, we composite the experimental results from two experiments. The first experiment is the structural hole analysis. For the first one, this study employs a software package for the analysis of social network data - UCINET version 6. The second one is for performing modified clustering, and CF using the result of the cluster analysis. We develop an experimental system using VBA (Visual Basic for Application) of Microsoft Excel 2007 for the second one. This study designs to analyzing clustering based on a novel similarity measure - Pearson correlation between user preference rating vectors for the modified clustering experiment. In addition, this study uses 'all-but-one' approach for the CF experiment. In order to validate the effectiveness of our proposed model, we apply three comparative types of CF models to the same dataset. The experimental results show that the proposed model outperforms the other comparative models. In especial, the proposed model significantly performs better than two comparative modes with the cluster analysis from the statistical significance test. However, the difference between the proposed model and the naive model does not have statistical significance.

• Journal of the Korean Institute of Landscape Architecture
• /
• v.46 no.3
• /
• pp.14-26
• /
• 2018

The Biotope Area Ratio (BAR) is a quantitative pre-planning index for sustainable development and an integrated indicator for the balanced development of buildings and outdoor spaces. However, it has been pointed out that there are problems in operations management: errors in area calculation, insufficiency in the underground soil condition and depth, reduction in biotope area after construction, and functional failure as a pre-planning index. To address these problems, this study proposes implementing LIM. Since the weights of the BAR are mainly decided by the underground soil condition and depth with land cover types, the study focused on the terrain and pavements. The model should conform to BIM guidelines and standards provided by government agencies and professional organizations. Thus, the scope and Level Of Detail (LOD) of the model were defined, and the method to build a model with BIM software was developed. An apartment complex on sloping ground was selected as a case study, a 3D terrain modeled, paving libraries created with property information on the BAR, and a LIM model completed for the site. Then the BAR was calculated and construction documents were created with the BAR table and pavement details. As results of the study, it was found that the application of the criteria on the BAR and calculation became accurate, and the efficiency of design tasks was improved by LIM. It also enabled the performance of evidence-based design on the terrain and underground structures. To adopt LIM, it is necessary to create and distribute LIM library manuals or templates, and build library content that comply with KBIMS standards. The government policy must also have practitioners submit BIM models in the certification system. Since it is expected that the criteria on planting types in the BAR will be expanded, further research is needed to build and utilize the information model for planting materials.

• The Journal of Korean Physical Therapy
• /
• v.15 no.3
• /
• pp.126-152
• /
• 2003

The purpose of this study was to evaluate the value of passive caudal gliding mobilization of the glenohumeral joint on the range of motion (ROM) of active and passive abduction; to evaluate the value of pain relief through visual analogue scale (VAS); to evaluate the correlation between improvement of shoulder abduction and intra-articular movement measured by fluoroscopy in frozen shoulder patients. The subjects consisted of twenty-one patients with clinically diagnosed frozen shoulder (11 males, 10 females) between 40 and 63 years of age (mean age : 52.7 years). The traction and caudal gliding mobilization based on the convex-concave rule in the resting position and at end range of abduction was peformed for 15 minutes per day and was repeated 10 times during a 2 week period. The ROM of abduction was measured by goniometer and pain was measured by VAS. The intra-articular movement was measured by fluoroscope, Neurostar Plus TOP (Siemens, Germany). ROM measurements of each patient was acquired at pre-treatment, immediate post-treatment and 2 week post-treatment. Statistical analysis was performed using SPSS 10.0 for Windows software and data was analyzed using the paired-test and the pearson correlation. The results of this study are as follows: 1. There was a significant decrease of VAS between pre-treatment data and 2 week post-treatment data (P<.05) but no significant difference between pre-treatment and immediate post-treatment data (P>.05). 2. There was a significant increase in ROM of active and passive abduction in the pre-treatment data, immediate post-treatment data, and in 2 week post-treatment data (P<.05). 3. With regard to results of the joint play test, there was a significant difference in the grade of traction between pre-treatment data and immediate post-treatment data and between pre-treatment data and 2 week post-treatment data (P<.05). There was no significant difference between immediate post-treatment data and 2 week post-treatment data (P>.05). 4. With regard to results of the joint play test, there was a significant difference in the grade of caudal gliding between pre-treatment data and immediate post-treatment data and between pre-treatment data and 2 week post-treatment data (P<.05). There was no significant difference between immediate post-treatment data and 2 week post-treatment data (P>.05), 5. With regard to the results of fluoroscopic findings, there was a significant change of the glenohumeral joint space between pre-treatment data and immediate post-treatment data and between immediate post-treatment data and 2 week post-treatment data (P<.05). There was no significant change of the glenohumeral joint space between immediate post-treatment data and 2 week post-treatment data (P>.05). 6. With regard to the results of fluoroscopic findings, there was a significant change of acromiohumeral joint space between the three data (pre-treatment data, immediate post-treatment data, 2 week post-treatment data) (P<.05). 7. Mobility grade by joint play test was significantly increased and was correlated to improved ROM of active and passive abduction (P<.05). In this study of frozen shoulder, passive caudal gliding techniques of the glenohumeral joint results in statistically significant changes in active and passive abduction as well as in VAS. There is also a significant correlation between joint play test and ROM of abduction.

• Journal of radiological science and technology
• /
• v.29 no.3
• /
• pp.167-175
• /
• 2006

With the recent prevalence of helical CT and multi-slice CT, which deliver higher radiation dose than conventional CT due to overbeaming effect in X-ray exposure and interpolation technique in image reconstruction. Although multi-detector and helical CT scanner provide a variety of opportunities for patient dose reduction, the potential risk for high radiation levels in CT examination can't be overemphasized in spite of acquiring more diagnostic information. So much more concerns is necessary about dose characteristics of CT scanner, especially dose efficient design as well as dose modulation software, because dose efficiency built into the scanner's design is probably the most important aspect of successful low dose clinical performance. This study was conducted to evaluate z-axis geometric dose efficiency in single detector CT and each level multi-detector CT, as well as to compare z-axis dose efficiency with change of technical scan parameters such as focal spot size of tube, beam collimation, detector combination, scan mode, pitch size, slice width and interval. The results obtained were as follows ; 1. SDCT was most highest and 4 MDCT was most lowest in z-axis geometric dose efficiency among SDCT, 4, 8, 16, 64 slice MDCT made by GE manufacture. 2. Small focal spot was 0.67-13.62% higher than large focal spot in z-axis geometric dose efficiency at MDCT. 3. Large beam collimation was 3.13-51.52% higher than small beam collimation in z-axis geometric dose efficiency at MDCT. 4. Z-axis geometric dose efficiency was same at 4 slice MDCT in all condition and 8 slice MDCT of large beam collimation with change of detector combination, but was changed irregularly at 8 slice MDCT of small beam collimation and 16 slice MDCT in all condition with change of detector combination. 5. There was no significant difference for z-axis geometric dose efficiency between conventional scan and helical scan, and with change of pitch factor, as well as change of slice width or interval for image reconstruction. As a conclusion, for reduction of patient radiation dose delivered from CT examination we are particularly concerned with dose efficiency of equipment and have to select proper scanning parameters which increase z-axis geometric dose efficiency within the range of preserving optimum clinical information in MDCT examination.