• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.16 no.5 s.96
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• pp.465-471
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• 2005

A method of calculation fur propagating and focusing of focused beams generated in antenna arrays, using BPM(Beam Propagation Method), is presented in this paper. Based on the diffraction theory, the beam focusing and Propagation is studied specially for the case of the antenna way fed by the Rotman lens that is able to focus microwave power on its focal arc or generate multiple beams. There are difficulties in performing a full-wave simulation using a commercial EM simulation tool for propagating and focusing of beams because of the structural complexity and the feeding assignment of the antenna array. Therefore, as an alternative solution, the BPM is presented to calculate the beam propagation from the aperture-type antennas. From the point of view of optics, the propagations of the lens have been simplified from the Fresnel diffraction integral to the Fourier transform. Using Fourier Transform, a beam propagation method is developed to show improvement of the resolution by controlling the wavefront of wave Propagating from an aperture-type antenna array. The beam width(or spot size) and the intensity are calculated for a focused beam propagating from an array having $10\lambda$ of its size. For the beams with $20\lambda,\;30\lambda$, and $50\lambda$ of geometrical focal length, the half-power beam widths(or spot size) are about 1.1\lambda,\;1.3\lambda,\;and\;1.9\lambda$ respectively.

• Korean journal of communication and information
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• v.62
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• pp.315-328
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• 2013

With a view to grasping how media commercialization is understood and discussed in the media-related academic community, this study compares and reviews other researches on the commercialization process of Korean press. Full-fledged studies have been rarely performed on the history of commercialization, but similar or related studies have been conducted intermittently: One is the commercialization theory in 1933 and the other is the commercialization theory in the late 1960s. Both of them decided Korean press had been commercialized as a strategical option in the midst of political pressure. It gives a clue leading us to understanding on why Korean press shows partisanship which is pointed as one of social maladies. Korean press acquires less economic benefits if they play in the market than if political parties they support or share the same political interest take power, so they are a commercial press as well as a partially partisan press. In this context, commercialization of Korean press is still underway, and genuine commercialization hitting the balance with politicization may have yet to begin.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.41 no.6
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• pp.710-717
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• 1996

To obtain the basic informations on the farm cultivation of Eleutherococcus senticosus Max., field survey of the native habitat in Mt. Deokyu such as weather, soils, vegetation and growth was carried out. The habitat of E. senticosus is situated at 127$^{\circ}$ 45'E, 35$^{\circ}$ 52' N in Mt. Deokyu where the elev-tion ranges from 1,050 to 1,300 meters above the sea level. Mean annual temperature forecasted around the habitat was 5.8$^{\circ}C$, mean maximum temperature in August, 24.6$^{\circ}C$ ; mean minimum temperature in January, -13.5$^{\circ}C$ and relative humidity during the growth periods, over 95%. To divide the area according to climatic conditions was classified cool temperature and humid rain forest zone. In another view, it belonged to deciduous broad-leaf forest zone and soil texture was sandy loam with dark brown gravels. Acidity and P$_2$O$_{5}$ content of soil represented pH 5.2～5.6 and 10ppm, respectively. The growth of E. senticosus was poor under the low light intensity(relative 20% of full sun-light) at the growing place of the habitat and the propagation was conducted by root sucker. The natural vegetation was consisted of big trees, 3 species; shrubs, 8 species and herbs, 4 species.

• Journal of the Korean Society of Tobacco Science
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• v.13 no.2
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• pp.5-20
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• 1991

For the quality enhancement of harvested-year leaf tobacco to the quality of 2-year naturally aged leaf tobacco, cellulose and nicotine degradative bacteria were isolated and identified. Effects of artificial fermentation treated cellulase and nicotine degradative bacteria on the quality of leaf tobacco were investigated from the chemical and sensory points of view. 1, Changes in chemical composition of leaf tobacco resulted from the addition of cellulase extracted from Cellulomonas sp. [3ml(${\mu}{\textrm}{m}$ D-glucose/ml. mil-1) of enzymes solution 11009 of leaf tobacco] and nicotine degradative bacteria, Pseudomonas sp. 2ml(IX109 cells$\div$ 100g of leaf tobacco), and subsequently fermented at 40${\mu}{\textrm}{m}$$^{\circ}C$, 65% R. H. for 40 days are as follows : 1) Content of crude fiber decreased 12% It took 9 min, 53 sec. to reach full combustion in control group but took only 7 min. 47 sec. in the treated group, taking almost equal time to 2-year naturally aged leaf tobacco(7 min. 35sec.). 2) Light intensity of control group was 60.96% with bright lemon color but that of treated leaf tobacco accounted for 47.69 with orange to dark brown color series, which was almost equal to the value, 45.69, of 2-year naturally aged leaf tobacco. 3) Linoleic acid, serving mild taste among organic acids, amounted to 1.llmg/g in control group but increased to 1.35m9/9 in the treated leaf tobacco, identical to the content(1.35mg/g) of 2-year naturally aged leaf tobacco. 4) Content of solanone, on of the typical leaf tobacco flavor compounds, accounted for 2.95% in control group but increased to 2.87% in treated group. 5) Methyl furan, useful flavor compound in smoke composition, accounted for 17.6$\mu\textrm{g}$/cig. in control group but increased to 25.9$\mu\textrm{g}$/cig. in treated group. However, acroleine decreased from 69.3$\mu\textrm{g}$/cig. in control group to 58.6$\mu\textrm{g}$/cig. in treated group 2. In sonsory test, mild taste evaluation of control group scored 5.47 and treated group 7.93 which was evaluted almost equal to the value(8.00) of 2-year naturally aged leaf tobacco. Aroma evaluation of control group scored 5.60, treated group 8.20, and 2-year naturally aged leaf tobacco 8.33. In addition, total harmony taste of control group showed 5.67, treated group 8.07 (p<0.01), and 2-year naturally aged leaf tobacco 8.00. From these results, it can be said that quality of treated leaf tobacco is not inferior to that 2-year naturally aged leaf tobacco.

• Korean journal of communication and information
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• v.28
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• pp.111-140
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• 2005

Most of studies on the press during the period of Japanese occupation in Korea have focused on the activities of newspapers in 1920s. These past studies didn't examine the whole process of change of the press under the Japanese occupation in Korea. Thus, this study tried to investigate the change of the tenor of Korean newspaper editorials on the ruling policies during the end of the colonial period in Korea as a part of attempts exceeding the limit of past studies. After the outbreak of the war between China and Japan in 1937, the Korean newspapers were full of stereotyped editorials resembling in a way official gazette. Dong-A Ilbo and Cho-Sun Ilbo represented the purpose of the war was to emancipate Asian countries from Western imperialist countries and to establish the peace of the Asia. Simultaneously, two newspapers played an important role in assimilating the Korean people into the Japanese and mobilizing them to the war, The tenor of these editorials was affected by intensified control over the press and the change of the consciousness of journalists. In conclusion, these newspapers had a harmful influence on the Korean people as a weapon to the movement to organize and mobilize them. Therefore the interest for researching on the pro-Japanese press should be taken in view of 'resistance' and 'collaboration.'

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.29 no.1
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• pp.50-60
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• 2018

In this paper, we developed a broadband multi-layered radome applicable for high-power applications. In this regard, we presented the wave propagation characteristics of the broadband multi-layered radome with the ABCD matrix and obtained the optimal thickness and the material constant for each layer by an optimization algorithm called "particle swarm optimization," implemented by a commercial numerical modeling tool. Further, we redesigned it in view of mechanical properties to reflect environmental conditions such as wind, snow, and ice. The power transmission property was reanalyzed based on the recalculated data of each layer's thickness to consider the limitations of the fabrication of a large structure. Under the condition of a peak electric field strength that is 10 dB above the critical electric field strength in air breakdown, we analyzed the air breakdown by radio frequency(RF) in the designed radome using the commercial full-wave electromagnetic tool. The radome was manufactured and tested by continuous wave(CW) RF small signal and large signal in an anechoic chamber. The test results showed good agreement with those attained by simulation.

• Journal of Korean Neurosurgical Society
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• v.61 no.3
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• pp.363-375
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• 2018

Intraoperative monitoring (IOM) utilizes electrophysiological techniques as a surrogate test and evaluation of nervous function while a patient is under general anesthesia. They are increasingly used for procedures, both surgical and endovascular, to avoid injury during an operation, examine neurological tissue to guide the surgery, or to test electrophysiological function to allow for more complete resection or corrections. The application of IOM during pediatric brain tumor resections encompasses a unique set of technical issues. First, obtaining stable and reliable responses in children of different ages requires detailed understanding of normal age-adjusted brain-spine development. Neurophysiology, anatomy, and anthropometry of children are different from those of adults. Second, monitoring of the brain may include risk to eloquent functions and cranial nerve functions that are difficult with the usual neurophysiological techniques. Third, interpretation of signal change requires unique sets of normative values specific for children of that age. Fourth, tumor resection involves multiple considerations including defining tumor type, size, location, pathophysiology that might require maximal removal of lesion or minimal intervention. IOM techniques can be divided into monitoring and mapping. Mapping involves identification of specific neural structures to avoid or minimize injury. Monitoring is continuous acquisition of neural signals to determine the integrity of the full longitudinal path of the neural system of interest. Motor evoked potentials and somatosensory evoked potentials are representative methodologies for monitoring. Free-running electromyography is also used to monitor irritation or damage to the motor nerves in the lower motor neuron level : cranial nerves, roots, and peripheral nerves. For the surgery of infratentorial tumors, in addition to free-running electromyography of the bulbar muscles, brainstem auditory evoked potentials or corticobulbar motor evoked potentials could be combined to prevent injury of the cranial nerves or nucleus. IOM for cerebral tumors can adopt direct cortical stimulation or direct subcortical stimulation to map the corticospinal pathways in the vicinity of lesion. IOM is a diagnostic as well as interventional tool for neurosurgery. To prove clinical evidence of it is not simple. Randomized controlled prospective studies may not be possible due to ethical reasons. However, prospective longitudinal studies confirming prognostic value of IOM are available. Furthermore, oncological outcome has also been shown to be superior in some brain tumors, with IOM. New methodologies of IOM are being developed and clinically applied. This review establishes a composite view of techniques used today, noting differences between adult and pediatric monitoring.

• The Journal of the Korea Contents Association
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• v.10 no.10
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• pp.334-350
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• 2010

This study aims at investigating the possible effects on the tax accounting practices stemming from adopting the IFRS in financial reporting process. It also seeks for policy implications to help alleviate practical conflicts likely to arise from the inconsistencies between the existing tax law and the tax related IFRS provisions. The results of the survey analysis are summarized as follows: firstly, majority opinion is opposed to the fair value based revaluation of property assets as well as the application of immediate recognition of foreign currency translation gains/losses. It favors the existing provision on asset securitization which adopts sales transaction view. Secondly, most of the respondents oppose the proposed amendments which allows dual classification of lease contracts on the ground. Third, functional currency appears acceptable on a conceptual level, even though a deep concern is expressed regarding the practical feasibility of computing taxable income using financial statements translated on the basis of functional currency on a practical viewpoint. Fourth, many respondents support the existing convention of recognizing depreciation expenses for taxation purposes and are in favor of the separation of accounting and tax books on a long-term basis. Fifth, the majority opinion approves the maintenance of existing tax reconciliation system and the recognition of expenses related with the doubtful accounts on reporting basis. Finally, a concern is raised with regard to the added burden of practical job loads needed to comply with the proposed amendments.

• The korean journal of orthodontics
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• v.37 no.5
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• pp.331-340
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• 2007

The aim of this study was to determine firstly the characteristics of esthetic lips in Korean females and secondly to measure the changes of the lips before and after anterior segmental osteotomy in bimaxillary protruded patients. Methods: Samples consisted of 30 models and 26 nonmodels, and 10 patients who had received anterior segmental osteotomy. Twelve linear measurements, 5 angular measurements, and the lip perimeter and area were measured. These results were compared for each group using unpaired and paired t-tests. Results: Full face width, nose to chin, upper vermilion height and angle, lateral heights at the point of the tips of Cupid's bow, central bow angle, and the lower lip to chin lengths were significantly greater in nonmodels than in models. However, overall lip width, lower vermilion height and angle, tip-to-tip of Cupid's bow lip perimeter, and lower vermilion area were greater in models than in nonmodels. Comparison of before and after anterior segmental osteotomy revealed that the values for the upper vermilion and lateral heights, the angle to Cupid's bow tip lengths, and upper vermilion area of post-operative patients had become similar to those of Korean female models. Our findings demonstrated that Korean female models have a fuller lower vermilion & thinner upper vermilion compared with nonmodel controls, as determined by the vermilion heights, angles, and areas. Conclusions: It will be helpful for clinicians to use these measurements as guidelines for improving patients' facial esthetics.

• Journal of the Korean Institute of Landscape Architecture
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• v.45 no.4
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• pp.118-130
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• 2017

During the landscape design process, landscape architects produce various forms of drawings to visualize the future designed landscape. This work thoroughly examines the process of the utilization of James Corner's theory and practice of representation. Since the early 1990s, Corner has explored the characteristics and functions of landscape architectural drawing theoretically. Specifically, Corner argued that the use of visual representation makes it difficult to achieve the full embodiment of all of the multisensory characteristics of a landscape. Thus, he explored new drawing techniques that alternatively visualize the landscape and generate creative ideas(i.e., imagination of drawing), rather than a realistic illustration of not-yet-actualized landscapes(i.e., instrumentality of drawing). Corner's theory has evolved throughout the mid and late-1990s as applied to landscape practice. Corner embraced ecology and implemented the theory and practice of Landscape Urbanism, thereby once again emphasizing the instrumentality of drawing. Whereas the early theory mainly explored a perspective view using collage and montage, Corner later began to stress the importance of the instrumentality again. For example, Corner employed a mapping technique based on the instrumental map and that simultaneously creatively transforms it. Corner's theory and practice of representation fully explored the identity of landscape architectural drawings and reflected the interaction between theory and practice. Thus, his design and theoretical works continue to have significant influence on present landscape practice and theory.