• Korean Journal of Radiology
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• v.22 no.4
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• pp.652-662
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• 2021

Objective: To investigate the association between CT imaging features and survival outcomes in patients with primary invasive mucinous adenocarcinoma (IMA). Materials and Methods: Preoperative CT image findings were consecutively evaluated in 317 patients with resected IMA from January 2011 to December 2015. The association between CT features and long-term survival were assessed by univariate analysis. The independent prognostic factors were identified by the multivariate Cox regression analyses. The survival comparison of IMA patients was investigated using the Kaplan-Meier method and propensity scores. Furthermore, the prognostic impact of CT features was assessed based on different imaging subtypes, and the results were adjusted using the Bonferroni method. Results: The median follow-up time was 52.8 months; the 5-year disease-free survival (DFS) and overall survival rates of resected IMAs were 68.5% and 77.6%, respectively. The univariate analyses of all IMA patients demonstrated that 15 CT imaging features, in addition to the clinicopathologic characteristics, significantly correlated with the recurrence or death of IMA patients. The multivariable analysis revealed that five of them, including imaging subtype (p = 0.002), spiculation (p < 0.001), tumor density (p = 0.008), air bronchogram (p < 0.001), emphysema (p < 0.001), and location (p = 0.029) were independent prognostic factors. The subgroup analysis demonstrated that pneumonic-type IMA had a significantly worse prognosis than solitary-type IMA. Moreover, for solitary-type IMAs, the most independent CT imaging biomarkers were air bronchogram and emphysema with an adjusted p value less than 0.05; for pneumonic-type IMA, the tumors with mixed consolidation and ground-glass opacity were associated with a longer DFS (adjusted p = 0.012). Conclusion: CT imaging features characteristic of IMA may provide prognostic information and individual risk assessment in addition to the recognized clinical predictors.

• Journal of the Korean Geotechnical Society
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• v.15 no.2
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• pp.43-71
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• 1999

This research is an experimental work of developing a construction material using municipal wastewater sludge as liner and cover materials for waste disposal landfill. Weathered granite soil and flyash, produced as a by-product in the power plant, were used as the primary additives to improve geotechnical engineering properties of sludge. For secondary additives, bentonite and cement were mixed with sludge to decrease the permeability and to increase the shear strength, respectively. Various laboratory test required to evaluate the design criteria for liner and cover materials, were carried out by changing the mixing ratio of sludge with the additives. Basic soil properties such as specific gravity, grain size distribution, liquid and plastic limits were measured to analyze their effects on permeability, compaction, compressibility and shear strength properties of mixtures. Laboratory compaction tests were conducted to find the maximum dry densities and the optimum moisture contents of mixtures, and their effectiveness of compaction in field was consequently evaluated. Permeability tests of variable heads with compacted samples, and the stress-controlled consolidation tests with measuring permeabilities of samples during consolidation process were performed to obtain permeability, and to find the compressibility as well as consolidational coefficients of mixtures, respectively. To evaluate the long term stability of sludges, creep tests were also conducted in parallel with permeability tests of variable heads. On the other hand, for the compacted sludge decomposed for a month, permeability tests were carried out to investigate the effect of decomposition of organic matters in sludges on its permeability. Direct shear tests were performed to evaluate the shear strength parameters of mixed sludge with weathered granite, flyash and bentonite. For the mixture of sludge with cement, unconfined compression tests were carried out to find their strength with varying mixing ratio and curing time. On the other hand, CBR tests for compacted specimen were also conducted to evaluate the trafficability of mixtures. Various test results with mixtures were assessed to evaluate whether their properties meet the requirements as liner and cover materials in waste disposal landfill.

• Tuberculosis and Respiratory Diseases
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• v.62 no.5
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• pp.427-431
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• 2007

The bronchus-asociated lymphoid tissue(BALT) lymphoma is a low-grade primary malignant lymphoma that originates from bronchus associated lymphoid tissue. A 67-year-old woman was admitted for evaluation of cough, sputum, rhinorrhea which had persisted for one month. Physical examination showed decreased breathing sound on the left upper lung field. High resolution chest computed tomography demonstrated consolidation which showed air-bronchogram and surrounding ground glass opacity in left upper lobe. These findings implicated inactive tuberculosis, organizing pneumonia, or bronchiolo-alveolar carcinoma. The histologic findings from percutaneous needle aspiration biopsy revealed aggregated atypical small lymphoid cells with lymphoepithelial lesions. With immunohistochemical staining, the atypical lymphoid cells reacted positively with CD 20 antibody and negatively with CD 3 antibody. Thus, we could diagnosed her as a patient with BALT lymphoma. After left upper lobectomy, she has been well without recurrence of the disease for 14 months. In this country of Republic of Korea, it was the 1st case of BALT lymphoma surgically treated when histological diagnosis had been done. Based on this case, we wanted to demonstrate the importance of early histological diagnosis and treatment of BALT lymphoma.

• Journal of Chest Surgery
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• v.9 no.2
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• pp.298-310
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• 1976

A clinical analysis was performed on 118 cases of the benign esophageal diseases experienced at Department of Thoracic Surgery, Seoul National University Hospital during 20 year period from 1957 to 1976. Of 118 cases of the benign esophageal diseases, there were 84 patients of esophagenal stenosis, 14 of esophageal perforation, 8 of esophageal atresia, 7 of achalasia, 2 of hiatal hernia, 2 of esophageal foreign body and one of esophageal diverticulum. Fifty-one patients were male and sixty-seven were female, and ages ranged from one day to sixty-four years with peak incidence in the age group of 20 to 29 years. All but one of the esophageal stenosis were caused by corrosive esophagitis and ages ranged from three to sixty-four years with peak incidence in third decade. Main symptoms of the esophageal stenosis were dysphagia, weight loss and chest pain in order and mostly began between one month and one year after ingestion of corrosive agents. Corrosive esophageal stenosis developed most frequently in middle one-third of the esophagus and about one-forth of them were diffuse. Operations were performed on 72 patients of esophageal stenosis of whom 26 patients had esophagocologastrostomy, 21 gastrostomy, 20 esophagogastrostomy, 4 esophagojejunogastrostomy and 2 pharyngogastrostomy. There were 5 deaths in the postoperative period, an operative mortality of 6.9 percent, and 20 patients had one or two complications; eight were anastomotic leaks, 6 gangrenes of replaced loop, 4 wound abscesses and others. The causes of the esophageal perforation were traumatic in 7 cases, caustics in 4 and spontaneous in 3, and the most frequent site of the perforation was lower one-third of the esophagus. Frequent symptoms of the esophageal perforation were pain, fever, dysphagia and dyspnea, and preoperatively there were mediastinitis in 8 cases, empyema in 7, lung abscess in 3 and others. All 14 patients of the esophageal perforation underwent operation: primary closure in 7 cases, drainage in 4, esophagogastrostomy in 2 and 'esophageal diversion in one. There were 4 postoperative deaths and 11 postoperative complications occurred in 7 patients. The duration of symptoms in achalasia was between 3 months and 25 years, with an average duration of 6. 2 years. Frequent symptoms of the achlasia esophagi were dysphagia, regurgitation, pain and weight loss in order. All 7 patients of achlasia underwent modified Heller's operation where 2 patients had complications, restenosis in one and esophageal perforation in another. All 8 patients of congenital esophageal atresia had distal tracheoesophageal fistula and were admitted within 5 days of life, but there were pneumonic consolidation on chest X-ray in patients. Five patients underwent one staged operation with the result of 2 deaths and one anastomotic leak.

• Tuberculosis and Respiratory Diseases
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• v.79 no.1
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• pp.37-41
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• 2016

Iron supplements such as ferrous sulfate tablets are usually used to treat iron-deficiency anemia in some elderly patients with primary neurologic disorders or decreased gag reflexes due to stroke, senile dementia, or parkinsonism. While the aspiration of ferrous sulfate is rarely reported, it is a potentially life-threatening condition that can lead to airway necrosis and bronchial stenosis. A detailed history and high suspicion of aspiration are required to avoid delays in diagnosis and treatment. The diagnosis can be confirmed by bronchoscopic examination and a tissue biopsy. Early removal of the aspirated tablet prevents acute complications, such as bronchial necrosis, hemoptysis, and lobar consolidation. Tablet removal is also necessary to prevent late bronchial stenosis. We presented the first case in Korea of a ferrous sulfate tablet aspiration that induced severe endobronchial inflammation.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.10
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• pp.499-508
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• 2016

Injection molding is a method for manufacturing many products, wherein a plasticized resin is injected into a mold at high pressure and hardened. According to the method, the product can be manufactured into various forms, and the mass production of up to tens of thousands of products is possible. The purpose of this study was to determine the process conditions for manufacturing a door latch for automobiles, through an analysis of the injection molding method. To calculate an appropriate injection flow for injection molding, a primary analysis for comparing the injection time, pressure, flow pattern, consolidation range, shear stress, shear rate, and weld line, as well as a secondary analysis for determining the conditions for stabilizing the molding temperature, holding pressure, and cooling process, were conducted. The characteristics of injection molding, and their influence on the product quality are discussed. No weld line and pores were observed on the products that had been manufactured based on the process conditions determined above. In addition, there were no flaws regarding the deformation compared to the prototype. Therefore, the manufacture of a product under the conditions determined in this study can reduce the defect rate compared to the existing production, and the process is also more competitive due to reduced production time.

• The Korean Journal of Air & Space Law and Policy
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• v.18
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• pp.9-39
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• 2003

The rule of the Warsaw Convention of 1929 are well known and still being all over the world. The Warsaw Convention is undoubtedly the most widely accepted private international air law treaty with some 140 countries. In the international legal system for air transportation, the Warsaw Convention has played a major role for more than half century, and has been revised many times in consideration of the rapid developments of air high technology, changes of social and economic circumstances, need for the protection of passengers. Some amendments became effective, but others are still not effective. As a result, the whole international legal system for air transportation is at past so complicated and tangled. However, the 'Warsaw system' consists of the Warsaw Convention of 1929 the Guadalajara Convention of 1961, a supplementary convention, and the following six protocols: (1) the Hague Protocol of 1955, (2) the Guatemala Protocol of 1971, (3) the Montreal Additional Protocols, No.1, (4) the Montreal Additional Protocol No.2, (5) the Montreal Additional Protocol No.3, and (6) the Montreal Additional Protocol No.4. of 1975. As a fundamental principle of the air carrier's liability in the international convention and protocols, for instance in the Warsaw Convention and the Hague Protocol, the principle of limited liability and a presumed fault system has been adopted. Subsequently, the Montreal Inter-carrier Agreement of 1966, the Guatemala City Protocol, the Montreal Additional Protocol No.3, and the Montreal Additional Protocol No. 4 of 1975 maintained the limited liability, but substituted the presumed liability system by an absolute liability, that is, strict liability system. The Warsaw System, which sets relatively low compensation limits for victims of aircraft accidents and regulates the limited liability for death and injury of air passengers, had become increasingly outdated. Japanese Airlines and Inter-carrier Agreement of International Air Transport Association in 1995 has been adopted the unlimited liability of air carrier in international flight. The IATA Inter-Carrier Agreement, in which airlines in international air transportation agree to waive the limit of damages, was long and hard in coming, but it was remarkable achievement given the political and economic realities of the world. IATA deserves enormous credit for bringing it about. The Warsaw System is controversial and questionable. In order to find rational solution to disputes between nations which adopted differing liability systems in international air transportation, we need to reform the liability of air carriers the 'Warsaw system' and fundamentally, to unify the liability system among the nations. The International Civil Aviation Organization(ICAO) will therefore reinforce its efforts to further promote a legal environment that adequately reflects the public interest and the needs of the parties involved. The ICAO Study Group met in April, 1998, together with the Drafting Committee. The time between the "Special Group on the Modernization and Consolidation of the 'Warsaw system'(SGMW)" and the Diplomatic Conference must be actively utilized to arrange for profound studies of the outstanding issues and for wide international consultations with a view to narrowing the scope of differences and preparing for a global international consensus. From 11 to 28 May 1999 the ICAO Headquarters at Montreal hosted a Diplomatic Conference convened to consider, with a view to adoption, a draft Convention intended to modernize and to integrate replace the instruments of the Warsaw system. The Council of ICAO convened this Conference under the Procedure for the Adoption of International Conventions. Some 525 participants from 121 Contracting States of ICAO attended, one non-contracting State, 11 observer delegations from international organizations, a total of 544 registered participants took part in the historic three-week conference which began on 10 May. The Conference was a success since it adopted a new Convention for the Unification of Certain Rules for International Carriage by Air. The 1999 Montreal Convention, created and signed by representatives of 52 countries at an international conference convened by ICAO at Montreal on May 28, 1999, came into effect on November 4, 2003. Representatives of 30 countries have now formally ratified the Convention under their respective national procedures and ratification of the United States, which was the 30th country to ratify, took place on September 5, 2003. Under Article 53.6 of the Montreal Convention, it enters into force on the 60th day following the deposit of the 30th instrument of ratification or acceptation. The United States' ratification was deposited with ICAO on September 5, 2003. The ICAO have succeeded in modernizing and consolidating a 70-year old system of international instruments of private international law into one legal instrument that will provide, for years to come, an adequate level of compensation for those involved in international aircraft accidents. An international diplomatic conference on air law by ICAO of 1999 succeeded in adopting a new regime for air carrier liability, replacing the Warsaw Convention and five other related legal instruments with a single convention that provided for unlimited liability in relation to passengers. Victims of international air accidents and their families will be better protected and compensated under the new Montreal Convention, which modernizes and consolidates a seventy-five year old system of international instruments of private international law into one legal instrument. A major feature of the new legal instrument is the concept of unlimited liability. Whereas the Warsaw Convention set a limit of 125,000 Gold Francs (approximately US$ 8,300) in case of death or injury to passengers, the Montreal Convention introduces a two-tier system. The first tier includes strict liability up to l00,000 Special Drawing Rights (SDR: approximately US$ 135,000), irrespective of a carrier's fault. The second tier is based on presumption of fault of a carrier and has no limit of liability. The 1999 Montreal Convention also includes the following main elements; 1. In cases of aircraft accidents, air carriers are called upon to provide advance payments, without delay, to assist entitled persons in meeting immediate economic needs; the amount of this initial payment will be subject to national law and will be deductable from the final settlement; 2. Air carriers must submit proof of insurance, thereby ensuring the availability of financial resources in cases of automatic payments or litigation; 3. The legal action for damages resulting from the death or injury of a passenger may be filed in the country where, at the time of the accident, the passenger had his or her principal and permanent residence, subject to certain conditions. The new Montreal Convention of 1999 included the 5th jurisdiction - the place of residence of the claimant. The acceptance of the 5th jurisdiction is a diplomatic victory for the US and it can be realistically expected that claimants' lawyers will use every opportunity to file the claim in the US jurisdiction - it brings advantages in the liberal system of discovery, much wider scope of compensable non-economic damages than anywhere else in the world and the jury system prone to very generous awards. 4. The facilitation in the recovery of damages without the need for lengthy litigation, and simplification and modernization of documentation related to passengers. In developing this new Montreal Convention, we were able to reach a delicate balance between the needs and interests of all partners in international civil aviation, States, the travelling public, air carriers and the transport industry. Unlike the Warsaw Convention, the threshold of l00,000 SDR specified by the Montreal Convention, as well as remaining liability limits in relation to air passengers and delay, are subject to periodic review and may be revised once every five years. The primary aim of unification of private law as well as the new Montreal Convention is not only to remove or to minimize the conflict of laws but also to avoid conflict of jurisdictions. In order to find a rational solution to disputes between nations which have adopted differing liability systems in international air transport, we need fundamentally to reform their countries's domestic air law based on the new Montreal Convention. It is a desirable and necessary for us to ratify rapidly the new Montreal Convention by the contracting states of lCAO including the Republic of Korea. According to the Korean and Japanese ideas, airlines should not only pay compensation to passengers immediately after the accident, but also the so-called 'condolence' money to the next of kin. Condolence money is a gift to help a dead person's spirit in the hereafter : it is given on account of the grief and sorrow suffered by the next of kin, and it has risen considerably over the years. The total amount of the Korean and Japanese claims in the case of death is calculated on the basis of the loss of earned income, funeral expenses and material demage (baggage etc.), plus condolence money. The economic and social change will be occurred continuously after conclusion of the new Montreal Convention. In addition, the real value of life and human right will be enhanced substantially. The amount of compensation for damage caused by aircraft accident has increased in dollar amount as well as in volume. All air carrier's liability should extend to loss of expectation of leisure activities, as well as to damage to property, and mental and physical injuries. When victims are not satisfied with the amount of the compensation for damage caused by aircraft accident for which an airline corporation is liable under the current liability system. I also would like to propose my opinion that it is reasonable and necessary for us to interpret broadly the meaning of the bodily injury on Article 17 of the new Montreal Convention so as to be included the mental injury and condolence. Furthermore, Korea and Japan has not existed the Air Transport Act regulated the civil liability of air carrier such as Air Transport Act (Luftverkehrsgestz) in Germany. It is necessary for us to enact "the Korean Air Transport Contract Act (provisional title)" in order to regulate the civil liability of air carrier including the protection of the victims and injured persons caused by aircraft accident.