• Journal of the Korean Wood Science and Technology
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• v.21 no.3
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• pp.61-66
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• 1993

24mm-thick specimens from three species of plantation-grown softwood were press dried under two platen pressures of 1.75kgf/$cm^2$ and 3.50kgf/$cm^2$ to obtain drying information regarding to drying rate, thickness shrinkage and drying defects. The influence of platen pressure on drying fare in range of moisture content (30 to 10 percent) increased for pitch pine and larch, but reduced for korean white pine at higher pressure. Thickness shrinkage was increased at the higher pressure, and estimated thickness shrinkage at final MC of 10 percent became unrealistically greater for specimens containing higher final moisture content under the great influence of compressive strain. The effects of pressure on the amount of surface checks and honeycombing were different from species used. These species should have applied lower temperature than 177$^{\circ}C$ in this study to reduce surface checks and honeycombing.

• Korean Journal of Radiology
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• v.1 no.2
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• pp.84-90
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• 2000

Objective: To determine the effects of respiration on the size of lung cysts by comparing inspiratory and expiratory high-resolution CT (HRCT) scans. Materials and Methods: The authors evaluated the size of cystic lesions, as seen on paired inspiratory and expiratory HRCT scans, in 54 patients with Langerhans cell histiocytosis (n = 3), pulmonary lymphangiomyomatosis (n = 4), confluent centrilobular emphysema (n = 9), paraseptal emphysema and bullae (n = 16), cystic bronchiectasis (n = 13), and honeycombing (n = 9). Using paired inspiratory and expiratory HRCT scans obtained at the corresponding anatomic level, a total of 270 cystic lesions were selected simultaneously on the basis of five lesions per lung disease. Changes in lung cyst size observed during respiration were assessed by two radiologists. In a limited number of cases (n = 11), pathologic specimens were obtained by open lung biopsy or lobectomy. Results: All cystic lesions in patients with Langerhans cell histiocytosis, lymphangiomyomatosis, cystic bronchiectasis, honeycombing, and confluent centrilobular emphysema became smaller on expiration, but in two cases of paraseptal emphysema and bullae there was no change. Conclusion: In cases in which expiratory CT scans indicate that cysts have become smaller, cystic lesions may communicate with the airways. To determine whether, for cysts and cystic lesions, this connection does in fact exist, paired inspiratory and expiratory HRCT scans are necessary.

• Journal of the Korean Wood Science and Technology
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• v.15 no.2
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• pp.53-66
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• 1987

Korean red pine (Pinus densiflora S. et. Z.) and pitch pine(Pinus rigida Mill) $5{\times}10cm$ dimension lumber were dried in a kiln providing a cross-circulation velocity of 5 m/sec at dry-and wet-bulb temperatures of 116 and $71^{\circ}C$, followed by 3 hours at 91 and $85^{\circ}C$. Compared to dimension lumber dried lumber were as follows. 1. To dry to 10 percent moisture content, the high-temperatures schedule of Korean red pine and pitch pine lumber took less than one seventh the time required by the conventional kiln drying schedule. 2. High-temperature drying rate and conventional drying rate to 10 percent moisture content of Korean red pine lumber were 2.75 and 0.35%/hr, and those of pitch pine lumber were 3.38 and 0.46%/hr respectively. 3. Compared to lumber of both species on conventional schedule, moisture gradient of high-temperature lumber was greater. 4. Compared to lumber on conventional schedule, maximum surface checking of high-temperature lumber of both species was severer, and maximum end checking of high-temperature lumber of both species was similar to that of lumber on conventional schedule. 5. Compard to lumber on conventional schedule, Korean red pine lumber dried at high temperature showed more honeycombing, but pitch pine lumber dried at high-temperature showed significantly slighter honeycombing. 6. Compared to lumber on conventional schedule, the high-temperature lumber showed less warping lumber of both species. 7. Collapse and casehardening of Korean red pine and pitch pine lumber on both scheules were slight.

• Tuberculosis and Respiratory Diseases
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• v.65 no.4
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• pp.328-333
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• 2008

Desquamative interstitial pneumonia is an uncommon form of interstitial lung diseases and it has a good prognosis compared with other types of idiopathic interstitial pneumonia. A 69-year old man was admitted to our hospital because of a 3-month history of dyspnea. The patient presented with hypoxemia. High-resolution computerized tomography of the patient showed ground glass opacity and traction bronchiectasis with subpleural early honeycombing on the both lung fields. The pathologic findings of the video-assisted thoracoscopy lung biopsy were compatible with desquamative interstitial pneumonia, and irregularly distributed interstitial fibrosis and inflammation were observed at the peripheral parenchyme. Oral predinsolone was started; his symptoms and chest x-ray were improved, and so he stopped taking the prednisolone. Ten months later, the desquamative interstitial pneumonia recurred. We report here on a case of recurrent desquamative interstitial pneumonia with fibrotic lung disease.

• Tuberculosis and Respiratory Diseases
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• v.82 no.4
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• pp.277-284
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• 2019

Idiopathic nonspecific interstitial pneumonia (NSIP) is one of the varieties of idiopathic interstitial pneumonias. Diagnosis of idiopathic NSIP can be done via multidisciplinary approach in which the clinical, radiologic, and pathologic findings were discussed together and exclude other causes. Clinical manifestations include subacute or chronic dyspnea and cough that last an average of 6 months, most of which occur in non-smoking, middle-aged women. The common findings in thoracic high-resolution computed tomography in NSIP are bilateral reticular opacities, traction bronchiectasis, reduced volume of the lobes, and ground-glass opacity in the lower lungs. These lesions can involve diffuse bilateral lungs or subpleural area. Unlike usual interstitial pneumonia, honeycombing is sparse or absent. Pathology shows diffuse interstitial inflammation and fibrosis which are temporally homogeneous, namely NSIP pattern. Idiopathic NSIP is usually treated with steroid only or combination with immunosuppressive agents such as azathioprine, cyclophosphamide, cyclosporine, and mycophenolate mofetil. Prognosis of idiopathic NSIP is better than idiopathic pulmonary fibrosis. Many studies have reported a 5-year survival rate of more than 70%.

• Journal of the Korean Society of Radiology
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• v.79 no.5
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• pp.276-281
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• 2018

Immunoglobulin G4 (IgG4)-related lung disease has been actively studied over the past few years. Radiologic findings of IgG4-related lung disease vary among patients, but there are no long-term follow up studies regarding variations in imaging features over the course of disease progression. In two cases with relatively long-term follow up, diverse early and late computed tomography (CT) findings of IgG4-related lung disease are reviewed in this report. In contrast to nodular or diffuse ground-glass opacity, which was predominantly noted in CT scans at earlier stages of disease, honeycombing and traction bronchiectasis were regarded as late radiologic manifestations. Solid nodules might be visible in both early and late stages; however, development of new solid nodules and enlargement of preexisting nodules could occur during disease progression. Interlobular septal thickening and mediastinal/hilar lymphadenopathy were persistent, even in later stages of the disease. These findings might be useful in making an accurate and timely diagnosis of IgG4-related lung disease.

• Journal of Korean Society of Forest Science
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• v.36 no.1
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• pp.26-32
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• 1977

Press drying was used on sapwood and heartwood of oak (Qercus acutissima Carruthers) to find profitable means of drying low grade logs. This study was designed to investigate the process of press drying considering core temperature, current moisture content, drying rate, drying time, final moisture content, dimensional change and drying defects. The drying tests were conducted using 1.5 centimeter thick material at platen temperature of $175^{\circ}C$ and pressure of 35psi. The results were summarized as fallows. 1. Core temperature was divided into three stages of drying characterized by initial heating period, plateau temperature, and period of rising core temperature. Plateau temperature of heartwood material was higher and longer than that of sapwood material. 2. The predicting equation for change in drying rate of sapwood material was log y=-2.7925-0.0811x as function of time. That of heartwood material was log y=-3.3382-0.0468x. 3. Sapwood material reduced the moisture content from 59 to 2.5 percent in 45minutes. Heartwood material reduced the moisture content from 64 to 3.3 percent in 55 minutes. 4. Shrinkage during press drying were 20.4 percent in thickness direction and 2.5 percent in width direction. Recovery on equilibrium conditioning at 65 percent relative humidity and temperature of $20^{\circ}C$. were 11.4 percent in thickness direction and 49.4 percent in width direction. 5. Heartwood material developed severe honeycombing and moderate checking. The sapwood material dried without honeycombing, checking and collapse. All material kept wood flat.

• Journal of radiological science and technology
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• v.34 no.4
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• pp.305-314
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• 2011

The purpose of this study was to compare the findings on the chest low-dose CT (LDCT) images between the negative and positive groups for pneumoconiosis in the group exposed to inorganic dust. From May 30, 2007 to August 31, 2008, total 328 subjects were examined by a LDCT. LDCT images were read by a chest radiologist who has much experience for reading of pneumoconiosis. All subjects were classified into two groups based on digital images after consensus reading of two radiologists according to the ILO 2000 guidelines; negative group (87, 26.5%) without pneumoconiosis and positive group (241, 73.5%). Statistical analysis was performed using a SPSS 14.0. There were significant differences in age (60.9 vs. 65.0, p<0.001), and in dust expose duration (17.0 vs. 19.2, p=0.024) between two groups, but no significant difference in smoking (p=0.784). Of the 328 subjects, 13 diagnosis were extracted from 245 subjects (74.7%). Coronary artery calcification (CAC) was significantly higher in positive group than that in negative group (36.9% vs. 25.3%, p=0.049). Honeycombing showed higher frequency in positive group than in negative group (6.2% vs. 1.2%, p=0.079). Pneumoconiosis findings caused by inorganic dusts exposure showed the significant relation with CAC on LDCT images. Future studies need to prove that pneumoconiosis finding is independent risk factor for CAC using a coronary artery angiography.

• Tuberculosis and Respiratory Diseases
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• v.51 no.6
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• pp.597-602
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• 2001

A 47-years-old woman presented with a 2-month history of a dry mouth and dry cough. The patient had been taking medication for Sj$\ddot{o}$gren's syndrome for approximately 7 years. The chest radiography showed multiple cystic lesions and a hazy density in both lower lung fields. The HRCT showed a diffuse ground glass like appearance and multiple variable sized cystic lesions in both lung fields. After medication, the symptoms were aggravated. Bronchoscopy was preformed with a transbronchial lung biopsy. The biopsies showed an infiltration of lymphocytes, neutrophils, monocytes and histiocytes through the interstitial space of the alveola and a widening of the alveolar septa. However, the histological findings of the cysts were not obtained. Sj$\ddot{o}$gren's syndrome is a slowly progressive inflammatory autoimmune disease, which is characterized by lymphocyte mediated destruction of the exocrine glands, with pulmonary involvement in approximately 19-65%, High-resolution CT is a sensitive technique for assessing the pulmonary involvement in patients with Sj$\ddot{o}$gren's syndrome. Although a lung biopsy is not always necessary for establishing a diagnosis of an interstitial lung disease in Sj$\ddot{o}$gren's syndrome. A lung biopsy may reveal a wide spectrum of changes ranging from a mild inflammatory response to end stage fibrosis with honeycombing. Because of the predominantly peribronchiolar inflammatory infiltration and inspissated secretions the cysts were suspected to have been formed by the ball-valve phenomen. However, no definite evidence was obtained.

• Korean Journal of Radiology
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• v.22 no.2
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• pp.281-290
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• 2021

Objective: To assess the performance of content-based image retrieval (CBIR) of chest CT for diffuse interstitial lung disease (DILD). Materials and Methods: The database was comprised by 246 pairs of chest CTs (initial and follow-up CTs within two years) from 246 patients with usual interstitial pneumonia (UIP, n = 100), nonspecific interstitial pneumonia (NSIP, n = 101), and cryptogenic organic pneumonia (COP, n = 45). Sixty cases (30-UIP, 20-NSIP, and 10-COP) were selected as the queries. The CBIR retrieved five similar CTs as a query from the database by comparing six image patterns (honeycombing, reticular opacity, emphysema, ground-glass opacity, consolidation and normal lung) of DILD, which were automatically quantified and classified by a convolutional neural network. We assessed the rates of retrieving the same pairs of query CTs, and the number of CTs with the same disease class as query CTs in top 1-5 retrievals. Chest radiologists evaluated the similarity between retrieved CTs and queries using a 5-scale grading system (5-almost identical; 4-same disease; 3-likelihood of same disease is half; 2-likely different; and 1-different disease). Results: The rate of retrieving the same pairs of query CTs in top 1 retrieval was 61.7% (37/60) and in top 1-5 retrievals was 81.7% (49/60). The CBIR retrieved the same pairs of query CTs more in UIP compared to NSIP and COP (p = 0.008 and 0.002). On average, it retrieved 4.17 of five similar CTs from the same disease class. Radiologists rated 71.3% to 73.0% of the retrieved CTs with a similarity score of 4 or 5. Conclusion: The proposed CBIR system showed good performance for retrieving chest CTs showing similar patterns for DILD.