• Journal of Korean Neurosurgical Society
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• v.60 no.5
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• pp.577-583
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• 2017

Objective : Laminoplasty is an effective surgical method for treating cervical degenerative disease. However, postoperative complications such as kyphosis, restriction of neck motion, and instability are often reported. Despite sufficient preoperative lordosis, this procedure often aggravates the lordotic curve of the cervical spine and straightens cervical alignment. Hence, it is important to examine preoperative risk factors associated with postoperative kyphotic alignment changes. Our study aimed to investigate preoperative radiologic parameters associated with kyphotic deformity post laminoplasty. Methods : We retrospectively reviewed the medical records of 49 patients who underwent open door laminoplasty for cervical spondylotic myelopathy (CSM) or ossification of the posterior longitudinal ligament (OPLL) at Pusan National University Yangsan Hospital between January 2011 and December 2015. Inclusion criteria were as follows : 1) preoperative diagnosis of OPLL or CSM, 2) no previous history of cervical spinal surgery, cervical trauma, tumor, or infection, 3) minimum of one-year follow-up post laminoplasty with proper radiologic examinations performed in outpatient clinics, and 4) cases showing C7 and T1 vertebral body in the preoperative cervical sagittal plane. The radiologic parameters examined included C2-C7 Cobb angles, T1 slope, C2-C7 sagittal vertical axis (SVA), range of motion (ROM) from C2-C7, segmental instability, and T2 signal change observed on magnetic resonance imaging (MRI). Clinical factors examined included preoperative modified Japanese Orthopedic Association scores, disease classification, duration of symptoms, and the range of operation levels. Results : Mean preoperative sagittal alignment was $13.01^{\circ}$ lordotic; $6.94^{\circ}$ lordotic postoperatively. Percentage of postoperative kyphosis was 80%. Patients were subdivided into two groups according to postoperative Cobb angle change; a control group (n=22) and kyphotic group (n=27). The kyphotic group consisted of patients with more than $5^{\circ}$ kyphotic angle change postoperatively. There were no differences in age, sex, C2-C7 Cobb angle, T1 slope, C2-C7 SVA, ROM from C2-C7, segmental instability, or T2 signal change. Multiple regression analysis revealed T1 slope had a strong relationship with postoperative cervical kyphosis. Likewise, correlation analysis revealed there was a statistical significance between T1 slope and postoperative Cobb angle change (p=0.035), and that there was a statistically significant relationship between T1 slope and C2-C7 SVA (p=0.001). Patients with higher preoperative T1 slope demonstrated loss of lordotic curvature postoperatively. Conclusion : Laminoplasty has a high probability of aggravating sagittal balance of the cervical spine. T1 slope is a good predictor of postoperative kyphotic changes of the cervical spine. Similarly, T1 slope is strongly correlated with C2-C7 SVA.

• The Journal of Korean Medicine
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• v.29 no.1
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• pp.117-133
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• 2008

Objectives : Since ancient times, Koreans have applied medicinal spabaths for treatment of various diseases. The objective of this study was to investigate the effect of strontium, one of the common ingredients of such baths, experimentally on acute skin barrier damage. Materials and Methods : Male hairless mice, average weight 20g, were divided into six groups. Each group consisted of five mice. The first was the normal, non-treated group. The second was the control group with acute skin barrier damage intentionally induced by TS. The third was the Ba-Sr1 group bathed in 1mg/L strontium chloride before and after inducing acute skin barrier damage by TS. The fourth was the Ba-Sr7 group bathed in 7mg/L strontium chloride before and after inducing acute skin barrier damage by TS. The fifth was the Sr1 group bathed in 1mg/L of strontium chloride only after intentionally inducing acute skin barrier damage by TS. The sixth was the Sr7 group bathed in 7mg/L of strontium chloride only after intentionally inducing acute skin barrier damage by TS. External changes of skin, skin erythema level, transepidermal water loss level, and GOT and GPT level of each group were checked immediately before and after TS, 3 hrs, 5 hrs and 24 hrs after inducing acute skin barrier damage. Then, tissue samples were made and examined for damage to epithelial cells, stratum corneum, change of mucous polysaccharide in dermis and amount of mast cells. Statistical analysis was performed by one way-ANOVA, Scheffe and Duncan for a post hoc test and pairwise comparison for comparing for difference between each time. Statistical significance was achieved if the probability was less than 5% (p<0.05) Results : 1. From skin erythema and TEWL level indicating the function of the skin barrier, we can know that it is helpful to the skin barrier to bathe in a water solution including a low concentration of strontium. 2. In the control group with acute skin barrier damage induced by TS, skin barrier damage persisted until 3-5 hrs and recovered after 5-24 hrs. Differently from the control group, in the case of taking a bath in a water solution including strontium, skin barrier damage recovered after only 3-5 hrs. Therefore, the bath with a water solution including strontium can promote recovery of the skin barrier. 3. Bathing in water solution including a higher concentration of strontium was more beneficial to recovery of skin barrier damage. 4. There was no influence on serum GOT and GPT from bathing in a water solution including strontium. Conclusions : The strontium was effective for recovery and mitigation of acute skin barrier damage induced by tape stripping. I suggest that strontium (Sr) can be used as an external treatment medicine, addedinto bath water to treat acute skin barrier damage.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.46 no.5
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• pp.70-77
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• 2009

In an RFID network consisting of a single reader and many tags, a framed and slotted ALOHA, which provides a number of slots for the tags to respond, was introduced for arbitrating a collision among tags' responses. In a framed and slotted ALOHA, the number of slots in each frame should be optimized to attain the maximal efficiency in tag cognizance. While such an optimization necessitates the knowledge about the number of tags, the reader hardly knows it. In this paper, we propose a tag cognizance scheme based on framed and slotted ALOHA, which is characterized by directly taking a Bayes action on the number of slots without estimating the number of tags separately. Specifically, a Bayes action is yielded by solving a decision problem which incorporates the prior distribution the number of tags, the observation on the number of slots in which no tag responds and the loss function reflecting the cognizance rate. Also, a Bayes action in each frame is supported by an evolution of prior distribution for the number of tags. From the simulation results, we observe that the pair of evolving prior distribution and Bayes action forms a robust scheme which attains a certain level of cognizance rate in spite of a high discrepancy between the Due and initially believed numbers of tags. Also, the proposed scheme is confirmed to be able to achieve higher cognizance completion probability than a scheme using classical estimate of the number of tags separately.

• The Journal of the Korea Contents Association
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• v.13 no.11
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• pp.382-395
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• 2013

The providers of meteorological information want to know the level of satisfaction of forecast users with their services. To provide better service, meteorological communities of each nation are administering a survey on satisfaction of forecast users. However, most researchers provided these users with simple questionnaires and the respondents had to choose one answer among different satisfaction levels. So, the results of this kind of survey have low explanation power and are difficult to use in developing strategy of forecast service. In this study, instead of cost-loss concept, we applied satisfaction-dissatisfaction concept to the $2{\times}2$ contingency table, which is a useful tool to evaluate value of forecast, and estimated satisfaction value of 24h precipitation forecasts in Shanghai, China and Seoul, Korea. Moreover, not only the individual satisfaction value of forecast but the user group's satisfaction value was evaluated. As for the result, it is effective to enhance forecast accuracy to improve the satisfaction value of deterministic forecast user group, but in the case of probabilistic forecast, it is important to know the level of dissatisfaction of user group and distribution of probability threshold of forecast users. These results can help meteorological communities to search for a solution which can provide better satisfaction value to forecast users.

• Tuberculosis and Respiratory Diseases
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• v.45 no.6
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• pp.1123-1142
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• 1998

Background : The frequency of MOTT has risen as the prevalence of tuberculosis has been declining. Our country has been also. The most of MOTT was resistant to the major anti-tuberculous drugs. Method : To compare clinical characteristics and frequencies of MDR tuberculosis with MOTT, the author studied 65 patients showing AFB culture positive with sputum. The data were collected from 176 patients who had been admitted at the National Masan Tuberculosis Hospital from May to June, 1997 to April, 1998. Result : The frequency of MDR tuberculosis was 43.1% and that of MOTT was 9.2%. Among 65 isolated mycobacteria, 3 cases were M. intracellulare. 2 cases were M. fortuitum, and 1 case was unidentified MOTT. The most frequent age group in 65 culture positive patients was 4th decade and the mean age was 44. The mean age was 61 in MOTT and 42 in M. tuberculosis and had significant difference(p<0.01). The numbers with past history of treatment were 2.3 in MDR tuberculosis and 1.7 in non-MDR tuberculosis and had significant difference(p<0.05). At the time of admission, the most frequent regimen for the treatment of MDR tuberculosis was 24 months regimen(85.7%) with the 2nd line anti-tuberculosis drugs. For non-MDR tuberculosis, 9 or 12 months regimen (72.9%) with the 1st line anti-tuberculosis drugs and had significant difference (p<0.01). At the time of admission, the symptom of weight loss was shown in 84.7% of M. tuberculosis and 50.0% in MOTT and there was significant difference(p<0.05) between them. All of the MOTT were identified to be resistant against INH and PAS. Drug resistance rates to INH, OFX(p<0.01) and PAS(p<0.05) in MOTT were higher than in MDR. All of three M. intracellulare strains were resistant to INH, RFP, PAS and OFX. All of two M. fortuitum strains were resistant to most anti-tuberculosis drugs. And the other MOTT was resistant to INH, EMB and PAS. Conclusion : MOTT was more common in elderly patients than M. tuberculosis. MOTT cases should be considered to be the probability of multiple drug resistance and treatment failure during the 1st treatment because they showed more resistance to anti-tuberculosis drugs than M. tuberculosis cases. Therefore, there should be more careful investigations for clinical characteristics, natural history of disease, and efficient management for MOTT.

• Journal of the Korean Society of Marine Environment & Safety
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• v.19 no.2
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• pp.138-144
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• 2013

Large and small marine accidents which are related to vessel's navigation are happening continuously and these maritime accidents have caused loss of lives and properties, and serious maritime environmental pollution damage. It is also true that maritime pollution damage is increasing due to these accidents, probability of growth of seaborne volume and complicated maritime traffic environment. Korea, recently, is developing an evaluation index which can assess sea risk through the evaluation of maritime traffic environment and provide danger and general information with relation to maritime traffic environment on target sea area to evaluate maritime traffic safety. In this paper, we intend to confirm the validity of maritime traffic safety on the basis of vessel navigator's risk consciousness and various sailing conditions by using the ship handling simulator. To confirm the validity of sailing vessel's maritime traffic safety, we use analysis of variance. By using analysis of variance, we analyze vessel navigator's characteristics, distance, speed and encounter type between vessels. Through multiple comparison of each factor's risk difference, we can confirm the change of numerical value of risk difference in statistical aspect.

• Journal of the korean academy of Pediatric Dentistry
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• v.37 no.2
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• pp.207-212
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• 2010

Protein C deficiency increases the risk of thrombosis due to the lack of anticoagulant factor protein C. Among the numerous congenital protein C deficiencies, homozygous protein C deficiency has an especially low protein C activity level, that it is almost undetectable. It is a rare disease with a probability of 1:250000~500000. The signs and symptoms of homozygous protein C deficiency include purpuric, necrotic dermatosis, ecchymosis, blindness, and thrombosis in central nervous system. A 4-year-old girl was brought to the clinic with a chief complaint of extensive caries. The child was under warfarin medication in order to prevent possible complications during dental treatment. We consulted the pediatric department. Without warfarin intake, serious complications may occur due to thrombosis during dental treatment. Therefore, certain warfarin dosage (INR 3~5) and fresh frozen plasma as a backup for excessive hemorrhage were recommended. This child was a severely disabled child with the loss of vision, and it was difficult to manage her behavior effectively. Thus, dental treatment was carried out under general anesthesia, where bleeding control would be also easier to achieve.This report presents the case of a 4-year-old girl with protein C deficiency, who has received dental treatment for extensive caries under general anesthesia.

• Radiation Oncology Journal
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• v.37 no.3
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• pp.176-184
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• 2019

Purpose: It is unclear whether adding concurrent chemotherapy (CT) to definitive radiotherapy (RT) following induction CT is a tolerable and cost effective treatment for non-small-cell lung cancer (NSCLC) patients aged 70 years or older with comorbidities. This study evaluated the actual clinical outcomes between concurrent chemoradiotherapy (CCRT) and RT alone following induction CT or not in patients (≥70 years) in a single institution's clinical practice. Materials and Methods: A total of 82 patients with unresectable stage III NSCLC between 2004 and 2016 were retrospectively analyzed. Their treatment tolerance and clinical outcomes such as overall survival (OS), locoregional recurrence (LRR), treatment toxicities and distant metastasis (DM) were evaluated. Early mortality rates were also evaluated as 4-month mortality after RT. Results: Fifty-four patients received CCRT and 28 patients received RT alone. Induction CT before RT was performed for 68.5% and 50.0% in CCRT and RT alone groups. Treatment tolerance was significantly worse in CCRT (p = 0.046). The median survival was 21.1 and 18.1 months for CCRT and RT alone, which was not statistically significant. LRR and DM were also not different. Most early deaths after CCRT were attributed to non-cancer-related mortality. Acute esophagitis of grade ≥2 occurred more following CCRT (p = 0.017). In multivariate analysis, a Charlson Comorbidity Index (CCI) of ≥5 and a weight loss of ≥5% after RT were associated with poor OS. The factors adversely affecting 4-month survival were a CCI of ≥5 and CCRT. Conclusion: There were no significant differences in OS, LRR, and DM between CCRT and RT alone treatment in elderly patients. However, there was a poorer tolerance and higher incidence of acute esophagitis in the CCRT group. Specifically, when the patients had a CCI of ≥5, RT alone seems to be reasonable with a low probability of early death.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.42 no.3
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• pp.439-448
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• 2022

Recently, domestic small and medium-sized subcontractors participating in the overseas construction market are suffering from the continuous loss and damage due to the insufficient recognition of the importance of risk Sub-Clauses among conditions of subcontracts. Therefore, the need to derive risk Sub-Clauses for conditions of the subcontract has been raised, but until now, previous studies have been conducted focusing on deriving risk Sub-Clauses for standard conditions of contract for construction between the Employer and the Contractor. In this study, 52 risk Sub-Clauses were derived on the basis of the influence size of the Sub-Clauses through the Delphi technique targeting 94 Sub-Clauses of conditions of standard subcontract for construction edition 2011, issued by the International Federation of Consulting Engineers (FIDIC) and In addition, 33 key risk Sub-Clauses were finally derived through the PI Risk Matrix by Probability and Impact. The results of this study provide will useful information on key risk Sub-Clauses that need to be reviewed in advance to minimize contractual risks at the stage of bidding and signing contracts for overseas subcontract construction projects.

• Journal of Ocean Engineering and Technology
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• v.33 no.6
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• pp.518-525
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• 2019

Recently, the Sub-Committee on SDC (Ship Design and Construction) of IMO have discussed actively the technical issues associated with the second-generation intact stability criteria of ships. Generally, second generation intact stability criteria refer to vulnerability five modes ship stability which occurs when the ship navigating in rough seas. As waves passes the ship, dynamic roll motion phenomenon will affect ship stability that may lead to capsizing. Multi-tiered approach for second generation of intact stability criteria of IMO instruments covers apply for all ships. Each ship is checked for vulnerability to pure loss of stability, parametric roll, and broaching/surf-riding phenomena using L1(level 1) vulnerability criteria. If a possible vulnerability is detected, then the L2(level 2) criteria is used, followed by direct stability assessment, if necessary. In this study, we propose a new method to verify the criteria of the surf-riding/broaching mode of small ships. In case, L1 vulnerability criteria is not satisfied based on the relatively simple calculation using the Froude number, we presented the calculation code for the L2 criteria considering the hydrodynamics in waves to perform the more complicated calculation. Then the vulnerability criteria were reviewed based on the data for a given ship. The value of C, which is the probability of the vulnerability criteria for surf-riding/broaching, was calculated. The criteria value C is considered in new approach method using the Froude-Krylov force and the diffraction force. The result shows lower values when considering both the Froude-rylov force and the diffraction force than with only the Froude-Krylov force was considered. This difference means that when dynamic roll motion of ship, more exact wave force needs considered for second generation intact stability criteria This result will contribute to basic ship design process according to the IMO Second-Generation Intact Stability Criteria.