• Asia pacific journal of information systems
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• v.19 no.2
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• pp.117-137
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• 2009

Recently, intelligent traffic information systems have enabled people to forecast traffic conditions before hitting the road. These convenient systems operate on the basis of data reflecting current road and traffic conditions as well as distance-based data between locations. Thanks to the rapid development of ubiquitous computing, tremendous context data have become readily available making vehicle route planning easier than ever. Previous research in relation to optimization of vehicle route planning merely focused on finding the optimal distance between locations. Contexts reflecting the road and traffic conditions were then not seriously treated as a way to resolve the optimal routing problems based on distance-based route planning, because this kind of information does not have much significant impact on traffic routing until a a complex traffic situation arises. Further, it was also not easy to take into full account the traffic contexts for resolving optimal routing problems because predicting the dynamic traffic situations was regarded a daunting task. However, with rapid increase in traffic complexity the importance of developing contexts reflecting data related to moving costs has emerged. Hence, this research proposes a framework designed to resolve an optimal route planning problem by taking full account of additional moving cost such as road traffic cost and weather cost, among others. Recent technological development particularly in the ubiquitous computing environment has facilitated the collection of such data. This framework is based on the contexts of time, traffic, and environment, which addresses the following issues. First, we clarify and classify the diverse contexts that affect a vehicle's velocity and estimates the optimization of moving cost based on dynamic programming that accounts for the context cost according to the variance of contexts. Second, the velocity reduction rate is applied to find the optimal route (shortest path) using the context data on the current traffic condition. The velocity reduction rate infers to the degree of possible velocity including moving vehicles' considerable road and traffic contexts, indicating the statistical or experimental data. Knowledge generated in this papercan be referenced by several organizations which deal with road and traffic data. Third, in experimentation, we evaluate the effectiveness of the proposed context-based optimal route (shortest path) between locations by comparing it to the previously used distance-based shortest path. A vehicles' optimal route might change due to its diverse velocity caused by unexpected but potential dynamic situations depending on the road condition. This study includes such context variables as 'road congestion', 'work', 'accident', and 'weather' which can alter the traffic condition. The contexts can affect moving vehicle's velocity on the road. Since these context variables except for 'weather' are related to road conditions, relevant data were provided by the Korea Expressway Corporation. The 'weather'-related data were attained from the Korea Meteorological Administration. The aware contexts are classified contexts causing reduction of vehicles' velocity which determines the velocity reduction rate. To find the optimal route (shortest path), we introduced the velocity reduction rate in the context for calculating a vehicle's velocity reflecting composite contexts when one event synchronizes with another. We then proposed a context-based optimal route (shortest path) algorithm based on the dynamic programming. The algorithm is composed of three steps. In the first initialization step, departure and destination locations are given, and the path step is initialized as 0. In the second step, moving costs including composite contexts into account between locations on path are estimated using the velocity reduction rate by context as increasing path steps. In the third step, the optimal route (shortest path) is retrieved through back-tracking. In the provided research model, we designed a framework to account for context awareness, moving cost estimation (taking both composite and single contexts into account), and optimal route (shortest path) algorithm (based on dynamic programming). Through illustrative experimentation using the Wilcoxon signed rank test, we proved that context-based route planning is much more effective than distance-based route planning., In addition, we found that the optimal solution (shortest paths) through the distance-based route planning might not be optimized in real situation because road condition is very dynamic and unpredictable while affecting most vehicles' moving costs. For further study, while more information is needed for a more accurate estimation of moving vehicles' costs, this study still stands viable in the applications to reduce moving costs by effective route planning. For instance, it could be applied to deliverers' decision making to enhance their decision satisfaction when they meet unpredictable dynamic situations in moving vehicles on the road. Overall, we conclude that taking into account the contexts as a part of costs is a meaningful and sensible approach to in resolving the optimal route problem.

• Tuberculosis and Respiratory Diseases
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• v.51 no.5
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• pp.409-415
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• 2001

Background : Multidrug-resistant tuberculosis(MDR-TB) in patients is mainly caused by acquired drug resistance. However, a small proportion of MDR-TB is caused by initial drug resistance(IDR), which may be somewhat different from acquired drug resistance. This study analyzed the clinical characteristics of IDR in MDR -TB patients to use the results as basic data in managing the disease. Methods : A retrospective study of 30 IDR cases in MDR-TB patients from Jan. 1995 to Dec. 1998 was performed. In order to analyze the clinical characteristics, the age, sex, family history, duration of negative conversion, number of resistant drugs, treatment regimens, duration of treatment, extent of disease and cavitary lesion on the chest X-ray was examined. In order to analyze the level of improvement, the extent of the disease and cavitary lesion on the chest X-ray, tested by Wilcoxon signed rank sum test, and the disease free interval rate of 1-year and 4-year was examined using the Kaplan-Meier method. Results : The mean age of the patients was 46.6 years and the sex ratio 1:1. Six(20%) patients had a family history. The mean negative conversion of the sputum AFB stain was 2.6 months. The number of resistant drugs was 7.6 and the number of used drugs 3.6. Twenty-three(67%) patients were treated for less than 12months and 28(93%) patients were treated with first-line drugs. The extent of the disease and the cavitary lesion on the chest X-ray improved after treatment(p<.05). Among 13 patients who were followed up for 22.6 months, 2(15%) patients relapsed and the disease free interval rate of I-year and 4-year was 85%. Conclusion: It is recommended that the duration of treatment of IDR in MDR-TB with first-line drugs be 9-12 months even if the extent of disease and cavitary lesion on the chest X-ray improves.

• Journal of Korea Port Economic Association
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• v.33 no.2
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• pp.53-82
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• 2017

The purpose of this study is to show the clustering trend and compare empirical results, as well as to choose the clustering ports for 3 Korean ports (Busan, Incheon, and Gwangyang) by using meta-frontier DEA (Data Envelopment Analysis) and integer models on 38 Asian container ports over the period 2005-2014. The models consider 4 input variables (birth length, depth, total area, and number of cranes) and 1 output variable (container TEU). The main empirical results of the study are as follows. First, the meta-frontier DEA for Chinese seaports identifies as most efficient ports (in decreasing order) Shanghai, Hongkong, Ningbo, Qingdao, and Guangzhou, while efficient Korean seaports are Busan, Incheon, and Gwangyang. Second, the clustering results of the integer model show that the Busan port should cluster with Dubai, Hongkong, Shanghai, Guangzhou, Ningbo, Qingdao, Singapore, and Kaosiung, while Incheon and Gwangyang should cluster with Shahid Rajaee, Haifa, Khor Fakkan, Tanjung Perak, Osaka, Keelong, and Bangkok ports. Third, clustering through the integer model sharply increases the group efficiency of Incheon (401.84%) and Gwangyang (354.25%), but not that of the Busan port. Fourth, the efficiency ranking comparison between the two models before and after the clustering using the Wilcoxon signed-rank test is matched with the average level of group efficiency (57.88 %) and the technology gap ratio (80.93%). The policy implication of this study is that Korean port policy planners should employ meta-frontier DEA, as well as integer models when clustering is needed among Asian container ports for enhancing the efficiency. In addition Korean seaport managers and port authorities should introduce port development and management plans accounting for the reference and clustered seaports after careful analysis.

• Journal of the korean academy of Pediatric Dentistry
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• v.46 no.4
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• pp.369-381
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• 2019

The aim of this study was to analyze the changes and improvements in symptoms of sleep-disordered breathing (SDB) using semi-rapid maxillary expansion (SRME) in children with narrow maxilla and SDB symptoms. Subjects were 15 patients with sleep disorder (apnea-hypopnea index, AHI ≥ 1) and narrow maxillary arch between 7 and 9 years of age. Before the SRME was applied, all subjects underwent pediatric sleep questionnaires (PSQ), lateral cephalometry, and portable sleep monitoring before expansion (T0). All subjects were treated with SRME for 2 months, followed by maintenance for the next 3 months. All subjects had undergone PSQ, lateral cephalometry, and portable sleep monitoring after expansion (T1). Adenoidal-nasopharyngeal ratio (ANR), upper airway width and hyoid bone position were measured by lateral cephalometry. The data before and after SRME were statistically analyzed with frequency analysis and Wilcoxon signed rank test. As reported by PSQ, the total PSQ scale was declined significantly from 0.45 (T0) to 0.18 (T1) (p = 0.001). Particularly, snoring, breathing, and inattention hyperactivity were significantly improved (p = 0.001). ANR significantly decreased from 0.63 (T0) to 0.51 (T1) (p = 0.003). After maxillary expansion, only palatopharyngeal airway width was significantly increased (p = 0.035). There was no statistically significant difference in position of hyoid bone after expansion (p = 0.333). From analysis of portable sleep monitoring, changes in sleep characteristics showed a statistically significant decrease in AHI and ODI, and the lowest oxygen desaturation was significantly increased after SRME (p = 0.001, 0.004, 0.023). In conclusion, early diagnosis with questionnaires and portable sleep monitoring is important. Treatment using SRME will improve breathing of children with SDB.

• Journal of Korea Port Economic Association
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• v.32 no.1
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• pp.29-58
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• 2016

The purpose of this paper is to show the clustering trend and the comparison of empirical results and is to choose the clustering ports for 3 Korean ports(Busan, Incheon and Gwangyang Ports) by using the bootstrapped DEA(Data Envelopment Analysis) and game Cross-efficiency models for 38 Asian ports during the period 2003-2013 with 4 input variables(birth length, depth, total area, and number of cranes) and 1 output variable(container TEU). The main empirical results of this paper are as follows. First, bootstrapped DEA efficiency of SW and LT is 0.7660, 0.7341 respectively. Clustering results of the bootstrapped DEA analysis show that 3 Korean ports [ Busan (6.46%), Incheon (3.92%), and Gwangyang (2.78%)] can increase the efficiency in the SW model, but the LT model shows clustering values of -1.86%, -0.124%, and 2.11% for Busan, Gwangyang, and Incheon respectively. Second, the game cross-efficiency model suggests that Korean ports should be clustered with Hong Kong, Shanghi, Guangzhou, Ningbo, Port Klang, Singapore, Kaosiung, Keelong, and Bangkok ports. This clustering enhances the efficiency of Gwangyang by 0.131%, and decreases that of Busan by-1.08%, and that of Incheon by -0.009%. Third, the efficiency ranking comparison between the two models using the Wilcoxon Signed-rank Test was matched with the average level of SW (72.83 %) and LT (68.91%). The policy implication of this paper is that Korean port policy planners should introduce the bootstrapped DEA, and game cross-efficiency models when clustering is needed among Asian ports for enhancing the efficiency of inputs and outputs. Also, the results of SWOT(Strength, Weakness, Opportunity, and Threat) analysis among the clustering ports should be considered.

• The Korean Journal of Nuclear Medicine Technology
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• v.13 no.3
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• pp.17-23
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• 2009

Purpose: It has been known that PET/CT is very valuable in follow-up study of diffuse large B cell lymphoma (DLBCL). Generally, in DLBCL, radiotherapy and chemotherapy has been progressed, because the lesion hasn‘t been limited to one site. And, it has lead to the decrease of leukocyte like neutropenia, due to myelosuppression of chemotherapy. So, in that case, administration of Filgrastim (Granulocyte colony-stimulating factor; G-CSF) is universal. However, in short time after administration, PET/CT has limitation to offer accurate images, through the uptake of $^{18}F$-FDG is increased in the region that is activated bone marrow by hematopoietic growth. Therefore, the aim of this study is that PET/CT in a certain period of time after administration of Filgrastim is able to show normal degree of $^{18}F$-FDG uptake. Materials and Methods: 10 patients under follow-up study of diffuse large B cell lymphoma were examined in this study from January, 2007 to January, 2009 (Male: 4 persons; Female: 6 persons; The mean age: 53.8 years old; The mean weight: 57.3 Kg). Using PET/CT (Discovery STe; GE Healthcare, Milwaukee, WI, USA), whole body images were acquired in 1 hour after $^{18}F$-FDG injection. For image analysis, each ROI ($120\;mm^2$) was drawn on $C^6$ (the sixth C-spine), $L_4$ (the forth L-spine), liver, spleen, and lung, then SUV (Standard Uptake Value)s were measured. We compared with each uptake between in 1-day and 5~7 days after administration of Filgrastim at same patient, so confirmed significance about these by SPSS version 12. Results: In case of $C_6$, $L_4$, spleen, every SUV of 1 day later was remarkably higher than that of 5~7 days later, but liver and lung were similar. Also, the images acquired after 5~7 days distinct remarkably and show normal degree of $^{18}F$-FDG uptake, because uptake of bone was almost disappeared. Conclusions: In this study, each SUV was prominent difference as a period of time after Filgrastim’s administration. And Filgrastim makes concentrate uptake of $^{18}F$-FDG in bone, but, after 5~7 days, bone‘s uptake was greatly decreased. Therefore, we are able to infer a certain period of time that shows normal degree of uptake, by numerical value proven. Also, we consider that this study contribute to advanced study about the other agent like Pegfilgrastim, Lenograstim besides Filgrastim, afterwards.

• The Journal of Korean Society for Radiation Therapy
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• v.17 no.1
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• pp.1-8
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• 2005

Purpose : An effect of a packing to uterine treatment of a cervical cancer using a dose-volume histogram for a point dose and a volume dose of the bladder and the rectum was analyzed by establishing a three-dimensional treatment plan using a CT image. Materials and methods : Reference points of the bladder and the rectum were marked, respectively at a treatment plan device (plato brachytherapy V14.2.4) by photographing CT(marconi, USA) when the packing was used and removed under the same condition and a treatment plan was performed to Apoint depending on ICRU38. However, in case of the rectum, a maximum point was looked up and compared with the above point because the point presented from the ICRU is not proper as a representative value of a rectum point dose. Further, the volume dose depending on volume of $50\%,\;80\%,\;and\;100\%$ point doses of the rectum and the bladder was measured. The measured values were used to analyze the effect of the packing through a Wilcoxon Signed Rank Test (a SAS statistical analysis process program). Result : The reference points at the bladder and rectum doses when the packing was removed were $116.94\;35.42\%$ and $117.59\;21.08\%$, respectively. The points when the packing was used were $107.08\;38.12\%$ and $95.19\;21.32\%$, respectively. After the packing was used, the reference points at the bladder and the rectum were decreased by $9.86\%$ and $22.4\%$, respectively. When the packing was removed, the maximum points at the bladder and the rectum were $164.51\;50.89\%,\;128.81\;33.05\%$, respectively. When the packing was used, the maximum points at the bladder and the rectum were $142.31\;44.79,\;110.08\;37.03\%$, respectively. After the packing was used, the maximum points at the bladder and the rectum were decreased by $22.2\%$ and $18.73\%$, respectively. When the packing was removed, the bladder volume at $50\%,\;80\%,\;and\;100\%$ point doses of the rectum and the bladder were $48.62{\pm}18.09\%,\;16.12{\pm}11.15\%,\;and\;7.51{\pm}6.63\%$, respectively and its rectum volume were $23.41{\pm}14.44\%,\;6.27{\pm}4.28\%,\;2.79{\pm}2.27\%$, respectively. When the packing was used, the bladder volume at $50\%,\;80\%,\;and\;100\%$ point doses of the rectum and the bladder were $40.33{\pm}16.72,\;11.63{\pm}8.72,\;and\;4.87{\pm}4.75\%$, respectively and its rectum volume were $18.96{\pm}8.37\%,\;4.75{\pm}2.58\%,\;and\;1.58{\pm}1.06\%$, respectively. After the packing was used, the bladder volume at $50\%,\;80\%,\;and\;100\%$ point doses of the rectum and the bladder were decreased by $8.29\%,\;4.49\%,\;and\;2.64\%$, respectively and its bladder volume were decreased by $4.45\%,\;1.52\%,\;and\;1.21\%$, respectively. Conclusion : Values at Reference point doses of the bladder and the rectum recommended from the ICRU 38 were 0.0781 and 0.0781, respectively and values of their maximum point doses were 0.0156 and 0.0156, respectively, as a result of which an effect of the packing using at the uterine intracavitary treatment of an uterine cervical cancer through the three-dimensional treatment plan used CT were measured. That is, the values at reference point doses and the values at maximum point doses show similar difference. However, P value was 0.15 at over $50\%,\;80\%,\;and\;100\%$ volume doses and the value shows no similar difference. In other words, the effect of the packing looks like having a difference at the point dose, but actually shows no difference at the volume dose. The reason is that the volume of the bladder and the rectum are wide but the volume of the packing is only a portion. Therefore, the effect of decreasing the point dose was not great. Further, the farer the distance is, the more weak the intensity of radiation is because the intensity of radiation is proportional to inverse square of a distance. Therefore, the effort to minimize an obstacle of the bladder and the rectum by using the packing should be made.