• The Korean Journal of Soil Zoology
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• v.5 no.2
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• pp.101-112
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• 2000

Spiders usually have poor vision but not the jumping spiders. Their eight eyes are located on its distinctive box-shaped head and relatively well developed. The Spiders were fixated with 3% glutaraldehyde and thin section was performed with ultra-microtome. The specimens were observed with light microscopy, transmission and scanning electron microscopy. Eye area of jumping spider is competed of three rows. The first eye row comprise four eyes. Among them, two anterior median eyes are the largest and two anterior lateral eyes are relatively small. The former are main-eyes and have excellent vision. The second row, which has the two smallest eyes, is located about midway between the first and third rows. The third row is about half-way back on the thorax and eyed of which are middle size. To investigate ultrastructure of salticid spiders'eye, Menemerus fulvus was chosen. All of Menemerus fuvus's eyes are composed of cornea, lens, vitreous body and retina in histologically. Cornea layer, linked to exocuticle of exoskeleton. is regular layer structure without any cell tripe. Lenses are biconvex type. Retinas comprise well developed microvilli-shape rhabdomeres, unpigmented supporting cells, and pigmented cell. Retinas of anterior median eyes are surrounded by circular cylinder-shaped vitreous body, photoreceptor, i.e. rhabdomeres, of it is irregularly arranged compared to the other eyes.

• Journal of the Korean association of regional geographers
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• v.17 no.6
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• pp.649-665
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• 2011

Estuary of River Nakdong(in south-eastern coast of Korean Peninsula) is the most representative site of delta in Korea. This study is to elucidate morpho-structural background associated with the embayment area and sedimentation processes, having allowed development of the delta. In this area, Great morphological trait of the embayment area had been formulated by differential erosion exploiting regional fracture system(NNE-SSW, NNW-SSE, E-W,...) of tectonic origin. For this reason, outline of the embayment basin shows quadrangular plan, and ridges and dissected valleys of neighbouring mountains draw frequently morphological lineament pattern. At the last glacial age when delta deposit had not yet filled the actual embayment basin of the Nakdong, mechanical weathering(frost shattering) and mass-movement processes had provided detritus materials composed of blocks, boulders on bottom the basin. With the postglacial transgression in the Holocene, the basin had been submerged, then began to be filled with fluvio-marine deposits from Kimhae-Yangsan area toward actual estuarine zone, so that Nakdong delta have been formed. Analysis and synthesis of from hundreds of boring data of the delta area reveal that progression of delta formation have been accompanied with the development of barrier islands. If the barrier islands had grown as forming a plural row, then their intervals have posteriorly filled with another fluvio-marine deposits. Besides, it shows that delta deposits are essentially alluvial. However, at the periphery of the delta, intervention of fine marine deposits is frequently found.

• Restorative Dentistry and Endodontics
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• v.33 no.6
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• pp.499-506
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• 2008

The purpose of this study was to compare the push-out strength of a fiber post cemented with various resin cements. Newly extracted 36 human mandibular premolars which had single root canal were selected and their crown portions were removed. The root canal was instrumented using $PROTAPER^{TM}$ system and obturated using continuous wave technique. In each root, a 9-mm deep post space was prepared. #2 translucent fiber post (DT Light post, Bisco Inc., Schaumburg, IL, U.S.A.) was cemented using injection technique with Uni-dose needle tip (Bisco) and six different resin cements. The tested resin cements were Duo-Link (Bisco Inc., Schaumburg, IL, U.S.A.), Variolink II (Ivoclar-Vivadent AG, Schann, Liechtenstein), Panavia F (Kuraray Medical Inc., Okayama, Japan), Multilink Automix (Ivoclar-Vivadent AG, Schann, Liechtenstein), RelyX Unicem (3M ESPE Dental Products, St. Paul, MN, U.S.A.), and Maxcem (Kerr Co., CA, U.S.A.). After storage in distilled water for 24 hours, each root was transversally sectioned into approximately 1-mm thick sections. This procedure resulted in 6 serial sections per root. Push-out test wasperformed using a universal testing machine (EZ Test, Shimadzu Co.) with a crosshead speed of 1 mm/min. The data were analyzed with one-way ANOVA and Tukey HSD (p=0.05). The push-out strength of the groups which cemented fiber post with Panavia F and Multilink Automix were lower than those of the other groups. But, there were no statistically significant difference among groups at a probability level of 0.05.

• The Journal of the Korea Contents Association
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• v.9 no.11
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• pp.280-288
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• 2009

This study is to design and produce a detailed model for volume variety of three dimensional reconstruction images and to evaluate the changes of volume, area and the length of the model in the process of the reconstruction of RTP system. CT simulation was operated at the thickness of 1.25, 2.5, 5, 10mm and average, standard deviation of scan direction(X), thickness(Y), table movement direction(Z), area(A), and volume(V) of the three dimensional volume rendering, were measured according to the shape and thickness of the phantoms. As a result, at the thickness of 1.25, 2.5min, the phantom's shape decreased maximum 0.13cm(p<0.05) to the direction of X, Y, Z and length, area, volume decreased 0.1cm, $0.8cm^2$, $3.99cm^3$ which led to an approximate image of the phantoms. However, at the thickness of 5, 10mm, the phantom of the original form decreased maximum 0.58cm(p<0.05) and volume, area, length decreased maximum 0.45cm, $8.21cm^2$, $11.03cm^3$. Volume varieties according to the thickness and shape of the phantoms have occurred diversely, when CT simulation was operated, and it is considered that a clinically appropriate volume rendering can be obtained only when the thickness is below 3mm.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.8 no.1
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• pp.113-122
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• 1997

The purpose of this study was to examine brain structural abnormalities in autistic children. Magnetic resonance imaging(MRI) findings in 22 male children with a DSM-Ⅲ-R diagnosis of autistic disorder and 17 non-autistic male control children were investigated. The ratio measures by lineometry was used to examine the cerebrum, midbrain, cerebellum, brain stem and ventricular system. The left to right ratio of the lateral ventricle was larger in autistic children than in controls. The pons was significantly larger in autistic children than in controls, and the cerebellum was smaller in autistic children. There were no significant differences between autistic children and controls in the symmetricity of the fontral lobe, parietal lobe, occipital lobe and temporal lobe, and in the size of the midbrain and 4th ventricle. These findings suggest that autistic disorder may be related to structural impairment of the brain.

• Restorative Dentistry and Endodontics
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• v.34 no.1
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• pp.1-7
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• 2009

The purpose of this study was to compare the stress distributions of NiTi rotary instruments based on their cross-sectional geometries of triangular shape-based cross-sectional design, S-shaped cross-sectional design and modified rectangular shape-based one using 3D FE models. NiTi rotary files of S-shaped and modified rectangular design of cross-section such as Mtwo or NRT showed larger stress change while file rotation during simulated shaping. The stress of files with rectangular cross-section design such as Mtwo, NRT was distributed as an intermittent pattern along the long axis of file. On the other hand, the stress of files with triangular cross-section design was distributed continuously. When the residual stresses which could increase the risk of file fatigue fracture were analyzed after their withdrawal. the NRT and Mtwo model also presented higher residual stresses. From this result, it can be inferred that S-shaped and modified rectangular shape-based files were more susceptible to file fracture than the files having triangular shape-based one.

• Journal of Hospice and Palliative Care
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• v.14 no.2
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• pp.101-109
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• 2011

Purpose: The Assessing Care Of Vulnerable Elders project has developed indicators for the quality of the end-of-life (EOL) care. However, family members of cancer patients may have a different view on the quality indicators (QIs) established by health care experts. We evaluated the QIs from the family members' perspective. Methods: The information used in this study was gathered by surveying family members of cancer patients who were admitted to the inpatient hospice ward in Korea. A cross-sectional anonymous questionnaire was distributed to 120 potential respondents from July to October 2009. We included 69 responses in this study (effective response rate, 57.5%). Statistical analysis was performed by using SPSS for Win ver. 14.0, with independent t-test and Pearson's chi-square test. Results: Among QIs for good hospice care, families agreed the most on "Medical examination by the palliative care team or specialist" (88.4%) and "Dying in the family's presence" (88.4%). They agreed the least on "Discussing cardiopulmonary resuscitation with patients" (15.9%). Among QIs for bad hospice care, "Occurrence of fall or pressure ulcer are undesirable" showed the highest agreement rate (94.2%). The lowest agreement rate was 11.6% on "Dying in the hospital is undesirable." In addition, women, patients who were aware of their prognoses, and people with a high socioeconomic status tended to agree more on the QIs. Conclusion: Patients' families did not agree on some of the QIs recommended by previous studies. Family members' characteristics were related to their opinions on QIs.

• The Korean Journal of Zoology
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• v.38 no.3
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• pp.417-425
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• 1995

The present study was carried out to investigate the effect of microwave fixation in comparison with that of chemical fixation in preparing the microscopic samples. The microwave fixator was equipped with infrared-temperature sensor, and that was designed to compensate air temperature in the microwave fixator. In the microwave fixation, rat tongue was well preserved in terms of muscular fasciculus and pancreas stained by Feulgen reagents showed clear reaction products in the nucleus. Reaction products by PAS method in duodenal villi appeared specifically at the goblet cells. In electron microscopy, pancreatic cellular components such as secretory granules and collagen bundles were well preserved in both fixations. In aspect of histochemical reaction and electron microscopy, high quality was due to the protein content of microwave fixed specimen. The microwave fixation method saved total duration engaging microscopic preparation.

• Proceedings of the Population Association of Korea Conference
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• 2006.12a
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• pp.113-128
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• 2006

The main theme of this paper was to investigate the role of education as a source of economic growth in Korea. In this study, first, the objective mode was built by extending neoclassical Solow growth theory. Second, the capital deepening typical of an endogenous economic per-capita growth model was developed empirically for seven East-Asian economies as for the medium term, during $1975{\sim}2004$. And then we found the meaning of coefficients of growth factors, direct relative contribution of each input to per-capita growth in seven East-Asian countries, relative indirect contribution of education to per-capita growth in Korea, accounting for difference due to accumulation in Korea. The indirect relative contributions of secondary and higher education and R&D to per-capita growth change the results somewhat. Secondary education is still the largest single contributor 83.6 percent of predicted growth is due to secondary school enrollment in Korea. Primary education comes second with 37.5 percent and followed by higher education at -52.9 percent. Physical investment gives 62.3 percent and unimproved raw labor contributes only -1.4 percent.

• Water for future
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• v.21 no.4
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• pp.399-406
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• 1988

Presented in this paper is a brief summary of the basic theory and observation from a laboratory investigation aimed at determining flow characteristics and ice jam topography in a sinuous channel, and in a single-bend channel. The sinuous channel comprised thirteen $90^{\circ}$ bends and was of comparatively small s\aspect ratio. The single-bend channel was a $180^{\circ}$ bend, which was an order of magnitude large in width as well as aspect ratios than the sinuous channel. The simulated ices were polyethylene and polypropylene beads and block. The streamwise velocities near the bottom were larger than that of surface in sinuous channel and forming ice jam in sinuous channel, this phenoumena were found strongly. Jams were generally thicker along the inner bank of bends. The path of maximum-streamwise velocity was displaced towards approachs side of the inner bank of bends. Radial variation of jam thickness was to be regular by increasing size of ice fragments. The rate of jam head progression around outer bank of the single bend was faster than that of inner bank and its velocity was roughly steady. With increasing Froude number, jm thickness became less uniformly distributed; being generally thicker along the inner bank and near the jam's toe. Two-layer model might be adaptable for the computing the streamwise velocity in shallow river bends. Two cells of secondary flow cound be expected in ice covered-river bends.