• The Journal of Korean society of community based occupational therapy
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• v.3 no.1
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• pp.1-10
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• 2013

Objective : This study investigates the impact of the musculoskeletal disorder prevention exercise program designed on the basis of agricultural work posture on the balance ability, Oswestry Disability level, and Psychosocial stress of participants from one rural village in Chungnam area. Method : The exercise program was provided to 21 farmers with musculoskeletal symptoms living in one village in Chungnam area. Such program was performed once a week, 90 minutes per session, for a total of twelve weeks from July 10 to October 11, 2008, and was constructed in a way to increase flexibility and muscular strength, taking agricultural work posture into account. The balance ability, Oswestry Disability Index, and Psychosocial Well-being Index scores were analyzed based on the data of 13 of the farmers who participated in the program for more than eight times and in all of the pre- and post-assessments. Result : Thirteen participants were all women who were 70.55(${\pm}6.78$) years old on average. Most of them were engaged in general dry-filed farming. The parts where they mainly felt the pain were low back(69.2%) and knees(61.5%), and 46.2% responded 'not healthy' to the question on the overall health status. The static balance ability when standing on the right foot significantly increased from the average 9.27(${\pm}5.53$) seconds before intervention to 14.22(${\pm}5.47$) seconds after intervention(p<.05). The Oswestry Disability Index showed a significant change, decreasing from the average 19.84(${\pm}6.89$) seconds to 14.38(${\pm}7.58$) seconds(p<.05). However, there was no change in the Psychosocial Well-being Index. Conclusion : This exercise program that has been conducted for the female farmers who are mainly engaged in the dry-filed farming has contributed to the improvement of their static ability and reduction of their Oswestry Disability Index scores. It is expected that the studies on the effects of the differentiated exercise programs depending on work characteristics will make progress in the future.

• Journal of Chest Surgery
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• v.31 no.9
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• pp.827-836
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• 1998

Background: Effective cardiopulmonary resuscitation (CPR) should provide acceptable hemodynamics for the vital organs during cardiac arrest and early restoration of spontaneous circulation that guarantees long-term, neurologically intact survival. CPR using heart-lung bypass has been suggested as an option for that use. This study was designed to determine the effectiveness of standard CPR techniques, closed-vs. open-chest CPR, which could be used in the future study verifying the role of heart-lung bypass CPR. Material and Method: By using adult mongrel dogs, closed-chest CPR (CCCPR, n=4) and open-chest CPR (OCCPR, n=5) were compared with respects to hemodynamics, restoration of spontaneous circulation(ROSC), and survival. Ventricular fibrillation-cardiac arrest (VF-CA) was induced by electrical shock in all animals. After 4 minutes of cardiac arrest, basic life support (BLS) was applied for 15 minutes and followed by advanced life support (ALS). ALS was maintained until achi ving ROSC but not longer than 30 minutes regardless of the recovery. Resuscitation procedures in either group were standardized by adopting the protocol of American Heart Association. Result: Prearrest baseline hemodynamic data was not different between two groups. During resuscitation, substantially higher systolic pressure was maintained in OCCPR group than in CCCPR group (45$\pm$15 vs. 33$\pm$11 mmHg during BLS, 83$\pm$36 vs. 44$\pm$15 mmHg during ALS; p=NS). Mean pulmonary arterial pressure went up to the level of mean systemic arterial pressures in CCCPR group and to half of that in OCCPR group, and had kept higher in CCCPR group throughout CPR (32$\pm$10 vs. 22$\pm$4 mmHg during BLS and 32$\pm$15 vs. 24$\pm$10 mmHg during ALS; p=NS). ROSC was obtained in 4 of 5 dogs receiving open-chest CPR and 2 of 4 closed-chest CPR. Prolonged survival was noted in all dogs in OCCPR group (6 to 1440 hours) but not in CCPR group (p<.05). Conclusion: These findings indicate that open-chest CPR can be more effective t maintain hemodynamics during cardiac arrest and to obtain restoration of spontaneous circulation and survival. Further experiment will be designed to compare heart-lung bypass CPR with open-chest CPR.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.12 no.2
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• pp.222-247
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• 1999

The back ground and purpose : The acupuncture of oriental medicine is very important in treatments. Until now it has been researched according to the meridian and qi xue(氣血) phenomenon of oriental medicine's theory. As electroacupuncture is one of acupuncture treatments, it will show more objective index to observe the meridian and qi xue(氣血) phenomenon. And then, I studied the effects on the thermal change of the face following electroacupuncture treatment. Objective and Methods : This study was performed from January 1999 to March 1999 on 10 healthy students. The objective was divided into three groups, those were the control group A(n=10), the group B(n=10) of electroacupuncture on Hapkok($LI_4$), Samgan($LI_3$) and the group C(n=10) of electroacupuncture on Shinmun($H_7$), T' ongni($H_5$). First, in the control group A, we took a picture for 10 men without any stimulation with the Digital Infrared Thermograph Imaging(D.I.T.I.) and did 3min after, 10min after, 15min after, 25min after, 45min after respectively. Second, in the electroacupuncture treatment group B, we took a picture for 10 men without any stimulation, and then treat electroacupuncture on Hapkok($LI_4$), Samgan($LI_3$) and took a picture immediately(3min after), 10min after, 15min after and remove needle and took a picture in the same way respectively. Third, in the electroacupuncture treatment group C, we took a picture for 10 men without any stimulation, and then treat electroacupuncture on Shinmun($H_7$), T'ongni($H_5$) and took a picture in the second way respectively. Results: 1. In healthy men, average skin temperture about Yonghyang($LI_{20}$) area was higher than Soryo($G_{25}$) or Chich'ang($S_4$) area. They were Soryo($G_{25}$) area $31.495{\pm}0.766^{\circ}C$, Rt. Yonghyang($LI_{20}$) area $31.664{\pm}0.936^{\circ}C$, Lt. Yonghyang ($LI_{20}$)area $31.686{\pm}0.767^{\circ}C$, Rt. Chich'ang($S_4$) area $31.226{\pm}0.875^{\circ}$, Lt. Chich'ang ($S_4$) area $31.453{\pm}0.855^{\circ}C$. 2. In the control group A, the skin temperature of Soryo($G_{25}$) showed the increase or decrease in below ${\Delta}0.1^{\circ}C\;except\;0.265{\pm}0.594^{\circ}C$ in 25min, but not significantly. 3. About Soryo($G_{25}$) area, the skin temperature decreased significantly after electroacupuncture immediately. ${\Delta}T $of the group B was $-0.970{\pm}0.87\;1^{\circ}C$, which was larger than one of the group C which was $-0.707{\pm}0.624^{\circ}C$ at 3min. And then ${\Delta}T$ of the group C was increase valuable at 25min, 45min. 4. About Yonghyang($L1_{25}$) area, the left ${\Delta}T$ of the group B showed below $0.2^{\circ}C$ or so in contrast to the right it. In the group C, on the both side showed continous increase of temperature as following times. 5. About Chich'ang($S_4$) area, the skin temperature increased valuable $0.3^{\circ}C$ or so on the both side and later inclined to decrease in the group B but not significantly. In the group C, it increased valuable on the both side. 6. The skin temperature of electroacupuncture treatment group B, C were more increase than the control group A except Lt. Yonghyang($LI_{20}$) area in the group B. The temperature of group C were more increase than the group B wholly. Conclusion : The above results indicate that D.I.T.I. is a useful method to observe and fallow-up the effects and the changes by electroacupuncture stimulation on objective evaluation of phenomenon for the meridian system and character. Thus, continuous thermographic study will be needed for more clinical application such as acupuncture and medicine or laser therapy according to oriental medicine.

• The Journal of Korean Society for Radiation Therapy
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• v.31 no.2
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• pp.25-31
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• 2019

Purpose: Metals induce metal artifact during CT-image for therapy planning, and it occurs images distortion, which affects the volumetric measurement and radiation calculation. In the case of using megavoltage computed tomography(MVCT), the volume of metals can be measured as similar to true volume due to minimal metal artifact outcome. In this study, radiation assessment was conducted by comparing teeth volume from images of kVCT and MVCT of head and neck cancer patients, then assigning to kVCT image to calculate radiation after obtaining the similar volume of true teeth volume from MVCT. Also, formal IR image was able to verify the accuracy of radiation calculation. Material and method: 5 head and neck cancer patients who had intensity-modulated radiation therapy from Radixact^® Series were of the subject in this study. Calculations of radiation when constraining true teeth volume out of kVCT image(A-CT) and when designated specific HU after teeth assigned using MVCT image were compared with formal IR image. Treatment planning was devised at the same constraints and mean dose was measured at the radiation assess points. The points were anterior of the teeth, between PTV and the teeth, the interior of PTV near the teeth, and the teeth where 5cm distance from PTV. Result: A difference of metals volume from kVCT and MVCT image was mean 3.49±2.61cc, maximum 7.43cc. PTV was limited to where the internal teeth were fully contained. The results of PTV dose evaluation showed that the average CI value of the kVCT treatment planning without the artifact correction was 0.86, and the average CI value of the kVCT with the artifact correction using MVCT image was 0.9. Conclusion: When the Treatment Planning was made without correction of metal artifacts, the dose of PTV was underestimated, indicating that dose uncertainty occurred. When the computerized treatment plan was made without correction of metal artifacts, the dose of PTV was underestimated, indicating that dose uncertainty occurred.

• Radiation Oncology Journal
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• v.28 no.4
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• pp.219-223
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• 2010

Purpose: To test the radiosensitizing effect of the newly synthesized novel histone deacetylase inhibitor, SK-7041 in vivo. Materials and Method: The RIF-l cell line was implanted into the back of a 6-week-old female C3H mouse, intradermally, The mice were grouped into control, drug, radiation (RT), and RT+drug group. SK-7041, 4 mg/kg was administered intraperitoneally for six cycles every 12 hours for mice in the drug and RT+drug group, An identical volume of phosphate buffered saline (PBS) was administered at the same frequency to mice in the control and RT groups. A single 5 Gy fraction was delivered to mice in RT and RT+drug group 6 hours after the fourth delivery. The volume of the implanted tumor was measured every 2~3 days to formulate the growth delay curve. Results: For the control, drug, RT, and RT +drug groups, the average duration for implanted tumor to reach a volume of $1,500mm^3$ was 10 days, 10 days, 9 days, and 12 days, respectively. Moreover, the tumor volume on D14 was $276.7mm^3$, $279.9mm^3$, $292.5mm^3$, and $185.5mm^3$, respectively (p=0.0004). The difference for the change in slope for the control and drug versus the RT and RT+drug groups were borderline significant (p=0.0650). Conclusion: The results of this study indicate that SK-7041 has a radiosensitizing effect for the RIF-1 cell line in vivo at a low concentration and this effect may be synergistic. Implementing this result to clinical trial is warranted.

• Journal of Intelligence and Information Systems
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• v.26 no.1
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• pp.135-149
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• 2020

Artificial intelligences are changing world. Financial market is also not an exception. Robo-Advisor is actively being developed, making up the weakness of traditional asset allocation methods and replacing the parts that are difficult for the traditional methods. It makes automated investment decisions with artificial intelligence algorithms and is used with various asset allocation models such as mean-variance model, Black-Litterman model and risk parity model. Risk parity model is a typical risk-based asset allocation model which is focused on the volatility of assets. It avoids investment risk structurally. So it has stability in the management of large size fund and it has been widely used in financial field. XGBoost model is a parallel tree-boosting method. It is an optimized gradient boosting model designed to be highly efficient and flexible. It not only makes billions of examples in limited memory environments but is also very fast to learn compared to traditional boosting methods. It is frequently used in various fields of data analysis and has a lot of advantages. So in this study, we propose a new asset allocation model that combines risk parity model and XGBoost machine learning model. This model uses XGBoost to predict the risk of assets and applies the predictive risk to the process of covariance estimation. There are estimated errors between the estimation period and the actual investment period because the optimized asset allocation model estimates the proportion of investments based on historical data. these estimated errors adversely affect the optimized portfolio performance. This study aims to improve the stability and portfolio performance of the model by predicting the volatility of the next investment period and reducing estimated errors of optimized asset allocation model. As a result, it narrows the gap between theory and practice and proposes a more advanced asset allocation model. In this study, we used the Korean stock market price data for a total of 17 years from 2003 to 2019 for the empirical test of the suggested model. The data sets are specifically composed of energy, finance, IT, industrial, material, telecommunication, utility, consumer, health care and staple sectors. We accumulated the value of prediction using moving-window method by 1,000 in-sample and 20 out-of-sample, so we produced a total of 154 rebalancing back-testing results. We analyzed portfolio performance in terms of cumulative rate of return and got a lot of sample data because of long period results. Comparing with traditional risk parity model, this experiment recorded improvements in both cumulative yield and reduction of estimated errors. The total cumulative return is 45.748%, about 5% higher than that of risk parity model and also the estimated errors are reduced in 9 out of 10 industry sectors. The reduction of estimated errors increases stability of the model and makes it easy to apply in practical investment. The results of the experiment showed improvement of portfolio performance by reducing the estimated errors of the optimized asset allocation model. Many financial models and asset allocation models are limited in practical investment because of the most fundamental question of whether the past characteristics of assets will continue into the future in the changing financial market. However, this study not only takes advantage of traditional asset allocation models, but also supplements the limitations of traditional methods and increases stability by predicting the risks of assets with the latest algorithm. There are various studies on parametric estimation methods to reduce the estimated errors in the portfolio optimization. We also suggested a new method to reduce estimated errors in optimized asset allocation model using machine learning. So this study is meaningful in that it proposes an advanced artificial intelligence asset allocation model for the fast-developing financial markets.

• Journal of Korean Ophthalmic Optics Society
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• v.14 no.4
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• pp.65-69
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• 2009

Purpose: Recently incidence of VDT syndrome has gradually increased as extensive use of computers. VDT syndrome reported by VDT workers include musculoskeletal disorder, neuropsychiatric disoders and eye symptoms such as eye strain, tired eyes, irritation and blurred vision. The environmental factors of VDT syndrome include electromagnetic waves, size, brightness and lighting of computer screen, height of a monitor and a worktable, working hours, kind of task, distance between screen and workers, indoor humidity and temperature, indoor air contamination and ventilation. In this study, we investigated the environmental factors related to body symptoms and health effects included in VDT syndrome. Methods: Study subjects were total 120 persons (54 male, 66 female) with age from 19 to 28. We surveyed the body symptoms and physical discomfort when doing an activity in a short distance such as reading book or paper, computer work. The questionnaire included main body symptoms, self-consciousness symptoms of eye, satisfaction of working environment, pain of the wrist when using keyboard and mouse. Results: Most of people (70%) felt physical pain from long time work of computer, paper, electrical apparatus. They mainly complained pain of neck and low back (57.1%), eye (45.2%) and head (31%). With the environmental factors, 78.3% of the subjects complaint pain of eye from inappropriate illumination. Most of the symptoms included 'eye fatigue'(38.3%), 'dryness of eye'(31.9%) and 'blurred vision'(23.7%). Subjects in this study complained discomfort of their chairs and most of them experienced pain in the wrist when using keyboard or mouse. Conclusions: When people use electrical apparatus or work with paper, people would get their eye fatigue and feeling of physical fatigue because of not harmonizing various environmental factors such as light, space, posture, worktable with theirselves. Therefore, workers should develop preventive method such as self-control of adequate break time to avoid fatigue while VDT work. Work environment should be changed to ergonomic design for optimal visual environment to prevent musculoskeletal disorder through constant research.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.2 no.2
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• pp.151-159
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• 1997

Benthic respiration and chemical fluxes were measured at the sediment-water interface underlying the marine fish cages floating on the open coastal waters off Tong-Young, the South Coast of Korea. The effects of cage farming on coastal benthic environment and on mass balance of organic carbon in the benthic boundary layer under the marine fish cages are addressed. In a growing season of caged fishes of June, 1995, benthic chambers and sediment traps were deployed on the sediment-water interfaces of the two sites chosen for this study: 1) Cage Site, directly underlying the fish cages of the farm at 18 m water depth, and 2) Control Site, about 100 m away from the farm at 32 m water depth. Benthic respiration rates and chemical fluxes were calculated from the evolution of dissolved oxygen and chemicals in the chamber water, and mass balance of organic carbon in the benthic boundary layer was constructed based on the vertical flux of particulate organic matter (POM) and chemical fluxes out of the sediment. High organic dumping (6400 mg C $m^{-2}d^{-1}$) and high benthic respiration (230 mmol $O_2\;m^{-2}d^{-1}$) were observed at the Cage Site. Equivalent to 40% of vertical flux of organic carbon into the Cage Site seemed to be decomposed concurrently and released back to overlying waters (2400 mg C $m^{-2}d^{-1}$). Consequently, up to 4000 mg C $m^{-2}d^{-1}$ of organic carbon could be buried into the farm sediment (equivalent to 60% of organic carbon flux into the Cage Site). At the Control Site, relatively less input of organic carbon (4000 mg C $m^{-2}d^{-1}$) and low benthic respiration rate (75 mmol $O_2\;m^{-2}d^{-1}$) were observed despite short distance away from the cages. The influence of cage farming on benthic chemical fluxes might be restricted and concentrated in the sea bottom just below the fish cages in spite of massive organic dumping and high current regime around the fish cage farm.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.33 no.2
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• pp.152-161
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• 2007

This study was conducted to patients visited oral maxillo-facial surgery, KNUH and the purpose of the study was to assess skeletal and dento-alveolar stability after surgical-orthodontic correction treated by skeletal Class III malocclusion patients with open bite versus non-open bite. This retrospective study was based on the examination of 40 patient, 19 males and 21 females, with a mean age 22.3 years. The patients were divided into two groups based on open bite and non-open bite skeletal Class III malocclusion patients. The cephalometric records of 40 skeletal Class III malocclusion patients (open bite: n = 18, non-open bite: n = 22) were examined at different time point, i.e. before surgery(T1), immediately after surgery(T2), one year after surgery(T3). Bilateral sagittal split ramus osteotomy was performed in 40 patients. Rigid internal fixation was standard method used in all patient. Through analysis and evaluation of the cephalometric records, we were able to achieve following results of post-surgical stability and relapse. 1. There was no significant statistical differences between open bite and non-open bite with skeletal Class III malocclusion patients in maxillary occlusal plane angle of pre-operative stage(p>0.05). 2. Mean vertical relapses of skeletal Class III malocclusion patients with open bite were $0.02{\pm}1.43mm$ at B point and $0.42{\pm}1.56mm$ at Pogonion point. In skeletal Class III malocclusion patients with non-open bite, $0.12{\pm}1.55mm$ at B point and $0.08{\pm}1.57mm$ at Pogonion point. There was no significant statistical differences between open bite and non-open bite with skeletal Class III malocclusion patients in vertical relapse(p>0.05). 3. Mean horizontal relapses of skeletal Class III malocclusion patients with open bite were $1.22{\pm}2.21mm$ at B point and $0.74{\pm}2.25mm$ at Pogonion point. In skeletal Class III malocclusion patients with non-open bite, $0.92{\pm}1.81mm$ at B point and $0.83{\pm}2.11mm$ at Pogonion point. There was no significant statistical differences between open bite and non-open bite with skeletal Class III malocclusion patients in horizontal relapse(p>0.05). 4. There were no significant statistical differences between open bite and non-open bite with skeletal Class III malocclusion patients in post-surgical mandibular stability(p>0.05). and we believe this is due to minimized mandibular condylar positional change using mandibular condylar positioning system and also rigid fixation using miniplate 5. Although there was no significant relapse tendency observed at chin points, according to the Pearson correlation analysis, the mandibular relapse was influenced by the amount of vertical and horizontal movement of mandibular set-back(p=0.05, r>0.304).

• Journal of the Korea Academia-Industrial cooperation Society
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• v.1 no.1
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• pp.73-82
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• 2000

Conventional funding system for the university research projects is limited to a grant or subsidy type funding method which does not require an obligation of refund. Such a funding system is known as ideal one for the university research activities which in general is not a profit oriented activities. It is considered ideal in a sense that nonprofit oriented research activities gives more emphasis on creativity than on efficiency or practical value. A venture- business-start-up research activity can not be considered as a pure nonprofit oriented activities. It clearly gives more emphasis on efficiency and practical value than on creativity Recently a large portion of the venture-business-start-up research activities are carried out in the universities. When a conventional research funding system is applied to such a new type of research activities, it turned out that the success rate is much lower than expectancy. This is why a new and differentiated funding system is sought for such a new type of research activities. A funding system of loan type for a venture-business-start-up research activities is proposed herewith. A loan system naturally requires a pay back after the successful start up of the venture business. This loan system nay be considered that a business concept is grafted on a conventional funding system for the university research activities. This means that a rather loose or generous terms and conditions of the money loan case is introduced into this funding system to remedy the short comings of the intrinsic nonprofit nature of the university research activities. The point is how to improve the success rate and how to reduce the undesirable aspect of the conventional university research activities when it is practiced with the new type of research activities. After one and half year of practicing with the new funding system. it can not be asserted that a definitely positive results could be obtained. but a trend of desirable aspects could be observed such as low drop out rate. project selection efficiency, higher sense of responsibility. etc.