• Journal of information and communication convergence engineering
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• v.7 no.4
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• pp.453-458
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• 2009

This paper presents two methods of designing a Broadband Impedance Matching (BIM) circuit for maximizing a power line communication (PLC) equipment (or Modem) signal injection into its load at any power line connection port. This optimal (BIM) circuit design is achieved in two phases: Butterworth gain function and Tchebycheff gain function. According to the comparison of simulation and practical results, the performances of two gain functions on BIM are discussed.

• Biomedical Science Letters
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• v.2 no.1
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• pp.57-69
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• 1996

To examine the process of spermiogenesis in the Korean red-backed vole, Clethrionomys rufocanus regulus, the seminiferous epithelium in the testis, was studied by trasmission electron microscopy, and the following results were obtained based on the morphological characteristics of cell differentiation. 1. According to the fine structural differentiation, spermiogenesis was divided into Golgi, cap, acrosome, maturation and spermiation phases. Besides, these phases were sub-divided into two steps : early and late phases respectively, Thus, the spermiogenesis of Clethrionomys rufocanus regulus was divided into a total of ten steps. 2. In the changes of the chromatin, the chromatin granules began to be condenced in the late Golgi phase, regularizated at maturation phases, and a perfect nucleus of sperm was formed at the spermiation phases. 3. The sperm head had the falciform, and the formative period of sperm tail began to be develop in the early Golgi phase and completed at the spermiation phases. 4. In the morphological features of spermiation phases, the spermatid of early spermiation phase was divided into three types : (1) A-type spermatid contained cytoplasmic droplets in the neck region and middle piece, and the mitochondria was irregular, and arranged around the axoneme. (2) B-type contained cytoplasmic droplet in the middle piece only, and the mitochondria are arranged the center of axoneme regularly, and (3) In the C-type spermatid, the arrangement of mitochondria was regular, and was contained cytoplasmic droplet in the neck region only. In the late spermiation phase, only the sperm head was surrounded by cytoplasm of Sertoli cell or the matured sperm just before the spermiation from the cytoplasm of Sertoli cell.

• Journal of Korean Medical classics
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• v.12 no.1
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• pp.197-224
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• 1999

The conception of 'earth(土)' belonging to the five evolutive phases(五行) is cognized that it is not partial to any side differing from other four phases and it can control other four phases so, it is the first gate to enter the process of changes. In the five organs(五臟), the spleen come under the earth phases and it have been very importantly considered for past to now in oriental medical history, for example by Li Dongyuan(李東垣). In this study, the results are summarized as the followings. 1. The term of the acquired constitution(後天) made by So-ong(邵雍), a scholar in the north so-dynasty, is used in the study of the book of changes(易經). And he said "The inborn constitution(先天) is the law of the nature itself and, the acquired constitution(後天) is the law of making the changes with the nature." In the myung-dynasty Li jungjae(李仲梓) made extract from this remarks 10 define that the spleen is the basis of the acquired constitution. So it considered that the the idea of changes(易) had an effect on the oriental medicine. 2. The one element of five phases, earth is the center of the changes and it composes the power of life with the sangsu(生數)-1, 2, 3, 4, and the sungsu(成數)-6, 7, 8, 9. In this process, the earth is the basis of the changes of the five phases. At the same time the spleen carry out the important physiological role in the humanbody controlling the other four organs. 3. In the change of the universe, the repetitionary movement of Yin(陰) and yang(陽) is the action of earth and it means illimitable division. In the course of this division all things change to new phases for example, the food changes 10 the ki(氣) through the action of spleen and stomach. So the organ of spleen and stomach is the space that the action of change occur. 4. Consequently the conception of bi(脾) is close to the pancreas that the spleen. And the duodenum is close to the conception of stomach because the space is the site of mito(未土). 5. The action of yin and yang in the ancient taegukdo(太極圖) is close 10 the connection of N-pole and S-pole. In the humanbody the two power is compared to the action of spleen and kidney, that means expansion and contraction. Also it means the inborn constitution and the acquired constitution so, it applyed to the all things in the universe.

• The Journal of Korean Society for Radiation Therapy
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• v.17 no.2
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• pp.125-131
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• 2005

Purpose : For stereotactic radiosurgery (SRS) of a tumor in the region whose movement due to respiration is significant, like Lung lower lobe, the gated therapy, which delivers radiation dose to the selected respiratory phases when tumor motion is small, was performed using the Respiratory gating system and its clinical effectiveness was evaluated. Materials and Methods : For two SRS patients with a tumor in Lung lower lobe, a marker block (infrared reflector) was attached on the abdomen. While patient' respiratory cycle was monitored with Real-time Position Management (RPM, Varian, USA), 4D CT was performed (10 phases per a cycle). Phases in which tumor motion did not change rapidly were decided as treatment phases. The treatment volume was contoured on the CT images for selected treatment phases using maximum intensity projection (MIP) method. In order to verify setup reproducibility and positional variation, 4D CT was repeated. Results : Gross tumor volume (GTV) showed maximum movement in superior-inferior direction. For patient #1, motion of GTV was reduced to 2.6 mm in treatment phases ($30{\sim}60%$), while that was 9.4 mm in full phases ($0{\sim}90%$) and for patient #2, it was reduced to 2.3 mm in treatment phases ($30{\sim}70%$), while it was 11.7 mm in full phases ($0{\sim}90%$). When comparing two sets of CT images, setup errors in all the directions were within 3 mm. Conclusion : Since tumor motion was reduced less than 5 mm, the Respiratory gating system for SRS of Lung lower lobe is useful.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.4 no.3
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• pp.55-65
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• 2001

The hydrological cycle system in the city is generally characterized by quick runoff, bad infiltration, low evaporation rate, and so on. It is caused by sealing greens up with pavements. Also, there are lots of contradictory environmental problems, such as inundation, the lack of underground water and dryness in the city, caused by the urban drainage system which is mostly focused on the quick draining off rainfall. In addition, the technique joining rain and sewage, which has more dangers of inundation, occupies 66% between two Korean drainage systems which consist of joining and dividing system. There has been some need to convert the present drainage system into the environmentally friendly hydrological cycle system. This is a theoretical study to examine some foreign cases and suggested applicable methods in our country, focusing on the environmentalyl friendly system of rainfall drainage. The precipitation treatment system can be made up of some possible phases choosing from premanagement, utilization, infiltration, retention, and inducement phases. Therefore, this study mostly focused on infiltration, retention, and inducement phases. It is necessary to suggest the multifunctional utilization of outdoor spaces, especially applying in new constructing and re-constructing residential estates.

• Bulletin of the Korean Chemical Society
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• v.29 no.6
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• pp.1229-1232
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• 2008

The surface structure, electrochemical behavior, and wetting property of self-assembled monolayers (SAMs) formed by dioctyl diselenide (DODSe) on Au(111) were investigated by scanning tunneling microscopy (STM), cyclic voltammetry (CV), and contact angle measurements. In contrast to the formation of well-ordered SAMs by octanethiol on Au(111), the SAMs formed by DODSe have a disordered phase and many unusual vacancy islands (VIs). In addition, the formation of DODSe SAMs is largely influenced by the solution concentration used. DODSe SAMs formed in 5 $\mu$ M and 50 $\mu$ M solutions have two mixed domains consisting of missing-row ordered phases and disordered phases, while DODSe SAMs formed in 1 mM and 5 mM solutions have only disordered phases with an abnormally high VI fraction of 22-24%. We also found that the wetting property and electrochemical behavior of DODSe SAMs on Au(111) are markedly influenced by the formation of ordered SAMs and the density of VIs.

• Hwankyungkyoyuk
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• v.21 no.4
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• pp.79-93
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• 2008

The purpose of this study was to develop an instrument for measuring elementary school students' environmental literacy. The process of instrument development was four phases. The first two phases involved defining the domain of the construct, writing an initial pool of 55 items, and reviewing the items for revision and deletion. These steps were taken to provide the evidence of content-related validity, and to reduce a number of items. The third phase was, through item analysis, to determine the most appropriate items for the environmental literacy for the elementary school students. For the forth phases, the fifth and sixth students in elementary school participated in this survey. To examine the reliability and validity of environmental literacy for the elementary school students, internal consistency estimate, and factor analysis were used. The results of this study were summarized as follows; Firstly, thorough factor analysis, we developed Environmental Literacy Instrument for the elementary school students, consisted of total 41 items (knowledge 8 items, emotion 11 items, skill 10 items, and behavior 13 items); Secondly, Cronbach's alpha was .783 for knowledge, .832 for emotion, .866 for skill and 8.61 for behavior.

• Transactions of the Korean Society of Automotive Engineers
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• v.9 no.5
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• pp.96-104
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• 2001

The present study experimentally investigates the concentration distribution of liquid and vapor phase with different injection timings in the in-cylinder flow field of a optically accessible engine. The conventional MPI, DOHC engine was modified into DI gasoline engine. The images of liquid and vapor phases in the motoring engine were captured by using exciplex fluorescence method. Dopants used in this study were 2% fluorobenzene and 9% DEMA(diethyl-methyl-amino) in 89% solution of hexane by volume respectively. Two dimensional spray fluorescence images of liquid and vapor phases were acquired to analyze spray behaviors and fuel distribution in the in-cylinder flow field. Measurements were carried out fur four different injection timings, namely BTDC 270$^{\circ}$, 180$^{\circ}$, 90$^{\circ}$, and 50$^{\circ}$. Experimental results indicate that behaviors and distribution of vapor phase were largely affected by in-cylinder tumble flow, and mixture formation process was also greatly affected by in-cylinder flow at early injection mode and by ambient pressure at late injection mode.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.13 no.1
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• pp.29-73
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• 1983

The age related changes in the life cycle of the progenitor cell population of murine oral epithelia was studied. Using radioautographic methods which have been adopted in previous cell cycle studies, the age-related changes of different phases in renewing cells of the palatal, buccal and lingual mucosae were determined. The results confirm published findings on cell cycle changes of epithelia with aging and illustrated further that mitotic phase which has hither to been considered stationary, also changes with aging. The major parts revealed by this study are as follows: 1) The basal progenitor cells in different regions of oral mucosa have different generation times. 2) The basal cell cycle time increases as a function of aging and the region most affected by aging appears to be the epithelium of the cheek. 3) The phases of the cell cycle affected by the process of aging are in increasing order of magnitude: M-, S- and G₁-phase. 4) The age elated change in the number of DNA synthesizing basal progenitor cells occurs at two age periods. Between 1 and 12 months of life it decreases, while from 12 to 20 months it increases.

• BMB Reports
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• v.36 no.2
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• pp.167-172
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• 2003

The kinetics of thermal inactivation of copper-containing amine oxidase from lentil seedlings were studied in a 100 mM potassium phosphate buffer, pH 7, using putrescine as the substrate. The temperature range was between $47-60^{\circ}C$. The thermal inactivation curves were not linear at 52 and $57^{\circ}C$; three linear phases were shown. The first phase gave some information about the number of dimeric forms of the enzyme that were induced by the higher temperatures using the "conformational lock" pertaining theory to oligomeric enzyme. The "conformational lock" caused two additional dimeric forms of the enzyme when the temperature increased to $57^{\circ}C$. The second and third phases were interpreted according to a dissociative thermal inactivation model. These phases showed that lentil amine oxidase was reversibly-dissociated before the irreversible thermal inactivation. Although lentil amine oxidase is not a thermostable enzyme, its dimeric structure can form "conformational lock," conferring a structural tolerance to the enzyme against heat stress.