• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.27 no.1
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• pp.1-12
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• 1991

An experiment has been carefully designed and performed to verify the theory for the echointergration technique of estimating the density of fish school by the use of steel spheres in a laboratory tank. The spheres used to simulate a fish school were randomly distributed throughout the insonified volume to produce the acoustic echoes similar to those scattered from real fish schools. The backscattered echoes were measured as a function of target density at tow frequencies of 50kHz and 200kHz. Data acquisition, processing and analysis were performed by means of the microcomputer-based sonar-echo processor including a FFT analyzer. Acoustic scattering characteristics of a 36cm mackerel was investigated by measuring fish echoes with frequencies ranging from 47.8kHz to 52.0kHz. The fluctuation of bottom echoes caused by the effects of fish-school attenuation and multiple scattering which occurred in dense aggregations of fishes was also examined by analyzing the echograms of sardine schools obtained by a 50kHz telesounder in the set-net's bagnet, and the echograms obtained by a scientific echo sounder of 50kHz in the East China Sea, respectively. The results obtained can be summarized as follows: 1. The measured and the calculated echo shapes on the steel sphere used to simulate a fish school were in close agreement. 2. The waveform and amplitude of echo signals by a mackerel without swimbladder fluctuated irregularly with the measuring frequency. 3. When a collection of 30 targets/m super(3) lied the shadow region behind another collection of 5 targets/m super(3), the mean losses in echo energy for the 30 targets/m super(3) were about -0.4dB at 50kHz and about -0.2dB at 200kHz, respectively. 4. In the echograms obtained in the East China Sea, the bottom echoes fluctuated remarkably when the dense aggregations of fish appeared between transducer and seabed. Especially, in the case of the echograms of sardine school obtained in a set-net's bagnet, the disappearance of bottom echoes and the lengthening of the echo trace by fish aggregations were observed. Then the mean density of the sardine school was estimated as 36 fish/m super(3). It suggests that when the distribution density of fishes in oceans is greater than this density, the effects of fish-school attenuation and multiple scattering must be taken into account as a possible source of error in fish abundance estimates. 5. The relationship between mean backscattering strength (, dB) and target density ($\rho$, No./m super(3)) were expressed by the equations: =-46.2+13.7 Log($\rho$) at 50kHz and =-43.9+13.4 Log($\rho$) at 200kHz. 6. The difference between the experimentally derived number and the actual number of targets gradually decreased with an increase in the target density and was within 20% when the density was 30 targets/m super(3). From these results, we concluded that when the number of targets in the insonified volume is large, the validity of the echo-integration technique of estimating the density of fish schools could be expected.

• Tuberculosis and Respiratory Diseases
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• v.39 no.1
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• pp.15-23
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• 1992

Background: The prognosis of lung cancer remains poor and early detection and curative surgery is still the most effective treatment for many. In the early detection of lung cancer, sputum cytology and simple chest x-ray are used, but both of these tests are far from being perfect. So we studied the characteristics of patients diagnosed as lung cancer without demonstrable mass lesion on simple chest x-ray to help in the early diagnosis of lung cancer. Methods: We conducted a retrospective study on 11 subjects who were diagnosed as lung cancer at Seoul National University Hospital between August 1986 and June 1989 and had no demonstrable mass lesion on simple chest x-rays. Results: Ten of 11 patients were male, 8 had a history of smoking, most frequent symptoms were sputum, cough, and hemoptysis, and 3 patients either had wheezing or stridor. In 3 of the cases, although there were no mass lesion, there were ill-defined infiltration, major fissure thickening, and fibrostreaky density mimiking tuberculosis where the tumor was eventually found and in one patient tumor was masked by a rib shadow. Also in one case, lateral chest film demonstrated a retrocardiac mass. Both bronchoscopy and computed tomogram were useful in the localization of the tumor. Seven of 11 had relatively early disease (less than StageII). Four of 11 are still alive without any evidence of recurrence between 2 and a half and 4 years after the operation. Conclusion: We conclude that in patients with respiratory symtoms in whom cancer cannot be ruled out, sputum cytology and lateral chest x-rays should be taken and that if necessary further studies like computed tomogram and bronchoscopy should be done to aid in the early diagnosis of lung cancer.

• Tuberculosis and Respiratory Diseases
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• v.41 no.2
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• pp.144-151
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• 1994

Background: Miliary tuberculosis almost always results from the discharge of infected caseous material into the blood stream, usually from a well hidden lymph node in the presentation of this disease in the past four decades, and although it is seen less frequent1y today than previously, its presentation and manifestation may require greater suspicion and diligence by the physician. We investigated the clinical characteristics, predisposing factors and accompanying diseases of miliary tuberculosis and tried to acquire the early diagnosis and treatment of this disease. Methods: A retrospective clinical study was done on 40 cases of miliary tuberculosis admitted to Hanyang University Hospital from Mar. 1989 to Dec.1992. The study investigated age and sex distribution, seasonal distribution, duration of symptoms before admission, pre-disposing factors, clinical symptoms, biochemical findings, chest X-ray findings, extrapulmonary tuberculosis associated with miliary tuberculosis, prognosis and mortality rate. Results: 1) The patients were most common in the age group between 20 and 29(23%) and the ratio of male to female was 1.4:1(male 23 : female 17). 2) Sputum smears for tubercle bacilli were positive in 5 cases(13%). 3) The most common clinical symptoms were fever with chilling(47.5%), coughing(47.5%), second most common symptom was dyspnea(32.5%), and the physical findings on admission were tachycardia(30%), weight loss(27.5%), meningeal signs(17.5%) in order. 4) The predisposing factors were heavy alcohol drinking(6 cases), steroid use(3 cases), pregnancy(2 cases) etc. 5) The chest X-ray findings on admission were miliary shadow only(40%), in addition pneumonic infiltration, pleurisy, and calcification in order. 6) The extrapulmonary tuberculosis associated with miliary tuberculosis were tuberculous meningitis(30%), bone and joint tuberculosis(17.5%), intestinal tuberculosis(15%) in order. 7) Biochemical findings were increased SGOT/SGPT(32.5%), increased alkaline phosphatase(32.5%), hypoalbuminemia(15%), hyponatremia(15%) etc. 8) About 4-6 weeks later after treatment(INH, RFP, PZA, EMB), 26 cases(65%) were improved on clinical symptoms or chest X-ray, 12 cases(30%) were stationary or aggravated, and 2 cases(5%) were died. Conclusion: For the early diagnosis and treatment of miliary tuberculosis, we must see its presentation and manifestation with greater interest and suspicion and investigate its predisposing factors and accompanying diseases.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.28 no.1
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• pp.27-37
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• 2010

This study tries to illuminate the features and values of the Buddhist temple Palkyung by closely examining the forms, structures, and meanings of Tongdo-palkyung(通度八景) handed down at Tongdosa Temple, the best among Korea's Buddhist temples with its three treasures of Buddha, law of Buddha and Buddhist monks. The findings of this study can be summarized as the following. First of all, it reveals the meaning of the geographical name Yeongchuksan(靈鷲山), located to the west of Tongdosa, and a spectacular sight spread like an eagle's spread wings, as well as its location and spatial features. In particular, the arrangement features of a number of attached hermitages clearly show Yeongchuksan's world as being a temple with buddhist treasures. The multi-layered unfolding and centripetal intention of the scenery can be perceived through the shape of the Sshangryongnongju(雙龍弄珠形), around Tongdosa and the feature of the enclosed landscape encircling the steps of Hyeolcheo(穴處) Geumganggyedan. The substances and components of Tongdopalkyung include sound-based spectacles derived from Beoneumgu(梵音具) creating sounds related to religious rituals to enlighten and redeem mankind, such as Yeongji(影池: a holy pond with shadow reflections), drum sounds, and bell sounds along with physical features like pine trees, Dae(臺), waterfalls, Dongcheon (洞天), and a glow in the sky. On the other hand, Palkyung's geographical arrangements exhibit a circular spatial formation based on the main motif as Buddhist symbolism, beginning with the 'Gukjangsangseokpyo(國長生石標)' awakening the territoriality of Tongdosa and locating the first scene 'Mupunghansong(舞風寒松)' in its introductory area, with the features of water, bridge, pine grove, and Iljumun(gate) to stand for the influx. Six other scenes including 'Anyangdongdae(安養東臺)' are placed in the sacred precincts around Daeungjeon and Geumganggyedan while the glow of sunset at 'Danjoseong' just outside the domain closes the symbolic circular formation of the Tongdopalkyung, which coincides with the development of the Mandala figure symbolizing 'Gusanpalhae(九山八海)' centered in Sumisan(須彌山). What is more, Tongdopalkyung, while excluding primary scenic elements inside the temple, maximizes the domain of the mountain's entrance and the effects of the multi-layered mountain, mountain upon mountain, by intensifying the influx and centripetal qualities. The Tongdopalkyung analysis reveals the antithesis of four-coupled scenes conveying buddhist principles and thoughts on the basis of seasons, directions, space and time to display a narrative structural landscape when viewed from the temple's territoriality. Likewise, the characteristics and porch structures of Tongdopalkyung are tools and language of symbols to both externally strengthen the temple's territoriality and to internally, maximize the desires to the Land of Happiness as well as intensify religious wishes and the Mandala's multi-layered qualities through the meanings of time and space.

• Journal of radiological science and technology
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• v.29 no.4
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• pp.267-274
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• 2006

The evaluation of GB stones with ultrasound has proved to be useful procedure in patient with symptoms of cholelithiasis. GB is evaluated for size, wall thickness, presence of internal reflections within the lumen and posterior acoustic shadowing or enhancement in Ultrsonography. The patient position should be shifted during procedure to demonstrate further the presence of stone within the GB. Patient scanned at the Rt. subcostal region in supine, right lateral, Lt. down decubitus, and upright sitting position. So GB stone should shift to dependent area of GB. Often, GB is not markedly distended in the presence of cholethiasis, and so the diagnosis becomes more difficult. One of the more difficult areas for detection of a GB stones are embeded in the cystic duct region. And since the GB is adjacent to the duodenum and hepatic flexure, its may be difficult to visualizing a GB stone. When patient study position changes frome supine to other position, stones displaced the site. But if its are polyps, not changes the site whatever patient positions. It is very important to what make different GB stones or polyps. We have studied about mobility of GB stones according to the patients position(supine, Lt. down decubitus, $30^{\circ} LAO. sitting and hand-knee). So we have a result, stones wherever localized within the GB, changed 100% its position in the hand-knee position and the others appeared at least 90%. In this study, when a large stones are located through fundus-body and body-neck, does not changing the stones position in spite of varied patient's positions. But hand-knee positions can identified GB stones, because its make changed the position of stons from posterior wall to anterior wall within the GB. We recommend the hand-knee position for differentiation GB stones from polyps.

• Journal of Science Education
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• v.38 no.3
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• pp.641-656
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• 2014

This study aimed at analyzing visual materials included in school science textbooks, specifically the textbooks for first semester courses of 3rd to 6th graders. The purpose was to provide directions for future textbooks by understanding the functions of the images in both pedagogical and social perspectives as well. The study was conducted by investigating the types, roles and socio-semiotic features of the images in science textbooks. The results were as follows. Firstly, the most used types of images in 2007 curriculum textbooks were photographs and drawn pictures. Uses of other visual aids than above were extremely rare. It was also found that as the educational level rises, the use of images for decorative functions drastically declined. The majority of the images were used in providing supplementary explanations or examples. This implies that the images effectively play the role of helping science education. In addition, more use of worksheets images was found, indicating that as educational level increases, students participate more actively in research sessions or data analysis. In socio-semiotic perspective, visual images showed high accessibility to students in 'Type of visual image', 'Function of visual image', 'Distance of shot', 'Horizontal angle of shot', 'Color moduation'. It was implied that there will a close correlation between the type, role and the socio-semiotic characteristics of visual images in textbooks. For example, photograph-type visuals were mostly used as supplementary references. And when applying the socio-semiotic analysis to photograph-type visuals, they showed 'real type', 'narrative-metaphor type', and 'shadow effect' among socio-semiotic features. Such correlations implied that knowing the type of the visual image may help determining the role of the image in the textbook to some extent, and also corresponding socio-semiotic characteristics. As a result, it was possible to infer how accessible certain visual images are to students. The above results have implications for the effective use of visual images in future textbooks.

• Journal of Korean Society of Transportation
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• v.23 no.3 s.81
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• pp.21-34
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• 2005

To control the obstacles surrounding aerodrome is significant for preventing air accident and ensuring the long sustaining of aerodromes. On the other hand, within a scope of ensuring safe flight operations, the application of Shielding is one of the issues to be importantly considered to manage efficiently the obstacles limitation around aerodromes, to dissolute the private asset privilege limitation from regulation on aerodrome circumference, and to decrease the pains to manage the obstacles, in terms of not only operating safely but also utilizing efficiently the airspace around aerodromes. The ICAO and other aviation-advanced states mitigate the construction limitation or exempt the obligation of obstacle sign by applying the shielding theory that the obstacles are not regarded as obstacles where are below the shadow surface. The Republic of Korea inserted the new regulation including the applying shielding similar to ICAO on Aviation Act and regulations. It is, however, hard to manage the aviation obstacles around aerodrome efficiently with these new regulation. Particularly, there exists much rooms to dispute because it cannot suggest the specific standard which is necessary to apply shielding theory at airspace of aerodromes. Therefore, in this study, the international standards on aviation obstacles were reviewed, analyzed and compared with those of domestic status. The direction of which guideline for control of aeronautical obstacles applicable within domestic circumstances as well as correspondent with international standard was suggested. Particularly, as far as the disputable application of shielding theory is concerned, the alternatives for aviation safety and efficient airspace operation by suggesting the clear standards alternatives were suggested.

• Korean Journal of Agricultural and Forest Meteorology
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• v.11 no.2
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• pp.72-78
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• 2009

The demand for rainfall data in gridded digital formats has increased in recent years due to the close linkage between hydrological models and decision support systems using the geographic information system. One of the most widely used tools for digital rainfall mapping is the PRISM (parameter-elevation regressions on independent slopes model) which uses point data (rain gauge stations), a digital elevation model (DEM), and other spatial datasets to generate repeatable estimates of monthly and annual precipitation. In the PRISM, rain gauge stations are assigned with weights that account for other climatically important factors besides elevation, and aspects and the topographic exposure are simulated by dividing the terrain into topographic facets. The size of facet or grid cell resolution is determined by the density of rain gauge stations and a $5{\times}5km$ grid cell is considered as the lowest limit under the situation in Korea. The PRISM algorithms using a 270m DEM for South Korea were implemented in a script language environment (Python) and relevant weights for each 270m grid cell were derived from the monthly data from 432 official rain gauge stations. Weighted monthly precipitation data from at least 5 nearby stations for each grid cell were regressed to the elevation and the selected linear regression equations with the 270m DEM were used to generate a digital precipitation map of South Korea at 270m resolution. Among 1.25 million grid cells, precipitation estimates at 166 cells, where the measurements were made by the Korea Water Corporation rain gauge network, were extracted and the monthly estimation errors were evaluated. An average of 10% reduction in the root mean square error (RMSE) was found for any months with more than 100mm monthly precipitation compared to the RMSE associated with the original 5km PRISM estimates. This modified PRISM may be used for rainfall mapping in rainy season (May to September) at much higher spatial resolution than the original PRISM without losing the data accuracy.

• Economic and Environmental Geology
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• v.49 no.4
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• pp.281-290
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• 2016

Coastal areas, used as human utilization areas like leisure space, medical care, ports and power plants, etc., are regions that are continuously changing and interconnected with oceans and land. Regular monitoring of coastal changes is essential at key locations with such volatility. But the survey method of terrestial LiDAR(Light Detection and Ranging) system has much time consuming and many restrictions. For effective monitoring coastal changes, KIOST(Korea Institute of Ocean Science & Technology) has constructed a shipborne mobile LiDAR system. The shipborne mobile LiDAR system, installed in a research vessel, comprised a land based LiDAR(RIEGL LMS-420i), an IMU(MAGUS Inertial+), a RTKGNSS(LEICA GS15 GS25), and a fixed platform. The shipborne mobile LiDAR system is much more effective than a land based LiDAR system in the measuring of fore shore areas without shadow zone. Because the vessel with the shipborne mobile LiDAR system is continuously moved along the shoreline, it is possible to efficiently survey a large area in a relatively short time. We conducted test measurements in the Anmok-Songjung beach around the Gangneung port. Effective monitoring of the changes using the constructed shipborne mobile LiDAR system for seriously eroded coastal areas will be able to contribute to coastal erosion management and response.

• Cartoon and Animation Studies
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• s.46
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• pp.63-84
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• 2017

Overwhelming images of vividly colored aircraft flying across the blue sky and steam gushing from massive machines are reminiscent of Japanese animation films, especially of works by master director Hayao Miyazaki. By presenting together steam engines, which are mechanical devices of the Industrial Age in the past, and aircraft of the future age, the director constructs ambiguous space and time. These special time and space constitute nostalgia for past time, with devices called steam engines as a medium, and a longing for science and the future as represented by aircraft. In addition, the anticipation and disappointment, ideals and regrets of humans who see these two from the perspective of the present are projected on the works. This shares the characteristic of the steam punk genre, which seeks to return to the past rather than to face current problems. A subgenre of science fiction (henceforth "sci-fi"), steam punk reflects fundamental skepticism of science and technology and mechanized civilization, which have developed beyond human control. In addition, as works that clearly display such characteristics, director Miyazaki's and < $Nausica{\ddot{a}}$ of the Valley of Wind> can be examined. With spectacles of steam engines and aircraft, these two works enticingly visualize narratives about nature and humans and about the environment and destruction. Such attractiveness on the part of the master director's works has led to support from fans worldwide. However, often in the backgrounds of director Miyazaki's works, which have depicted ideal worlds of nature, environment, and community as highly concentrated fantasies, lie presuppositions of war and the end of the world. As works that are especially prominent in such characteristics, there are and . These two works betray the expectations of the audience by establishing the actual wartime as the temporal background and proceeding toward narratives of reality. Trapped in the ontological identity of the director himself, the war depicted by him projects a subjective and romantic attitude. Such a problem stems also from the ambiguity of the hybrid space and time, which is basic to the steam punk genre. This is because the basic characteristic of steam punk is to transplant past time, which humans were able to control, in the future from a perspective of optimism and longing via steam engines rather than to face current problems. In this respect, steam punk animation films in themselves can be seen as having significance and limitations at the same time.