• Journal of the Korean Geotechnical Society
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• v.16 no.5
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• pp.213-226
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• 2000

지반 앵커(이하에서는 "앵커"로 칭한다)는 앵커두부, 자유부, 정착부로 나누어져 있다. 현재 주로 사용되고 있는 앵커는 지반과 앵커체 표면의 마찰저항력에 의해 지지하는 마찰방식이며, 앵커체에 발생하는 응력에 따라 크게 인장형과 압축형 앵커로 나누어진다. 그런데, 현재까지 이들 앵커의 설계 및 극한하중의 결정은 대부분이 인장형 앵커에 대한 것으로서, 긴장시 압축형 앵커의 선단정착부의 응력집중으로 이한 그라우트 압축저항에 대해서는 명확히 연구되어져 있지 않다. 본 연구에서는, 현장과 비슷한 조건에서 실내시험을 실시하여 선잔 장착부 그라우트의 보강형식에 따른 압축거동특성과 보강효과, 지반의 구속(정지와 포아송 구속)을 고려한 압축형 앵커의 선단 정착부 그라우트 압축저항력 산정식을 제안하였다.정식을 제안하였다.

• Proceedings of the KIEE Conference
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• 1987.07a
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• pp.284-287
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• 1987

In this paper, the design and implementation of a multiprocessor based Die Bonder Machine for the semiconductor will be described. This the partial research result, that is, the 1st year portion of the project to be performed for a period of two years from June, 1986 to May, 1988. The mechanical system consists of the following three subsystems : (i) transfer head unit, (ii) die feeding XY-table unit, and (iii) plunge up unit. The overall control system is designed to be essentially a master-slave type in which each slave is functionally fixed in view of software and also the time shared common bus structure with hardwired bus arbitration scheme is utilized, the control system consists of the following three subsystems each of which employs a 16 bits microprocessor MC 68000 : (i) die bonder processor controller, (ii) visual recognition/inspection and display system, (iii) the servo control system. It is reported that the proposed control system were applied to Working Sample and tested in real system, and the results are successful as a working sample phase.

• Archives of Craniofacial Surgery
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• v.11 no.1
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• pp.65-68
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• 2010

Purpose: Dermoid cysts are benign neoplasms that are derived from both ectoderm and mesoderm. Approximately 7 percent of all dermoid cysts occur in the head and neck, as most common sites are the lateral ends of the eyebrows, the midline in the nasal root and neck. Rarely they can be found in the frontal sinus, temporal bone, maxilla and the floor of the mouth. Dermoid cysts in the temporal fossa are extremely rare. We experienced a characteristic dermoid cyst that occupied the temporal fossa. Methods: A 16-year-old man had a progressive enlarging mass on the left eyebrow. Computerized tomographic scan showed a bulging mass in the temporal fossa, and it had the density similar to that of fat. The size of the mass was $3{\times}3{\times}2cm$, and it was composed of high density of fat with clear margin. There was no bony invasion, but the mass was fixed on bone. Results: We performed the surgery through coronal incision under general anesthesia. Because the mass was closely connected with temporal fat pads, we removed this mass with some portion of temporal fat pads, avoiding damage to the facial nerve. The postoperative course was ordinary without complication. Conclusion: The reports about dermoid cyst on the temporal fossa is uncommon. However, if there is a mass in the temporal fossa which has the density similar to that of fat in CT scan, we should consider the possibility of dermoid cyst. We suggest that excision through coronal incision with bewaring temporal fat pad can induce good result.

• Journal of Embryo Transfer
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• v.25 no.4
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• pp.237-245
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• 2010

Only an optimum number of viable spermatozoa in a frozen-thawed insemination dose can ensure conception at artificial insemination (AI). We report here the percentages of normal, abnormal and viable spermatozoa present in the frozen-thawed semen of 20 Black Bengal bucks used for commercial AI. Bucks in this experiment were of 19.3~46.1 months old and 25~42 kg body weight. Four semen straws (0.25 ml) from each buck were collected for evaluation of their kinetic parameters. Scrotal circumference was measured by using a scrotal tape, sperm motility was estimated on eye estimation and sperm concentration was determined by using a haemocytometer. Sperm morphology was studied in paraformaldehyde fixed spermatozoa under differential interference contrast (DIC) microscope. To determine the proportion of live (plasma membrane intact) spermatozoa, semen was stained with SYBR-14 and propidium iodide and examined under fluorescent microscope. Scrotal circumference, post-thaw sperm motility, sperm concentration per insemination dose and proportion of normal spermatozoa were $21.5{\pm}0.7\;cm$, $43.5 {\pm}5.4%$, $83.5{\pm}6.7$ million and $88.3{\pm}4.1%$, respectively. The percentages of spermatozoa with head shape and acrosome abnormalities were lower ($2.7{\pm}1.1$ and $1.4{\pm}1.3$, respectively), whereas higher percentages of abnormalities ($7.0{\pm}1.8$) were observed in mid piece and tail portion. The proportion of live spermatozoa was $28.5{\pm}5.4$. It is concluded that although a good number of morphologically normal spermatozoa are present in the insemination dose, the proportion of live spermatozoa is low, which warrants further improvements of buck semen freezing procedures to ensure good quality at AI.

• Applied Microscopy
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• v.24 no.1
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• pp.28-40
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• 1994

Xerostomia and xerophthalmia are delicate or serous side effects, occuring when the radiotherapy is administered to the head and neck cancer patient. It is known that the cause of the above side effect is radiosensitivity of serous cells. In this study, the ultrastructural features of the parotid glands of the X-irradiated rats were observed. Sprague-Dawley rats weighing 200-250g each were anesthetized with sodium thiopental, and placed on the Mitsubishi linear accelerator. Only the head and neck areas of animals were exposured at the distance of 80cm, within the area of $30X30cm$, in the depth of 1cm, with the speed of 200R/min. Total doses applied were 3,000R or 6,000R depending on the experimental groups. Animals were sacrificed on the 6th hour, 2nd day and 6th day after the irradiation. Parotid glands were fixed in the 2.5% glutaraldehyde-1.5% paraformaldehyde solution, and followed by refixation in the 1% osmium tetroxide solution. Dehydrated blocks were embedded in araldite mixture, and ultrathin sections were cut. Sections were contrasted with the solution of uranyl acetate and lead citrate, and observed with JEM 100 CX-II electron microscope. The results were as follows: 1. Normal parotid acinar cells are two types; the light and the dark acinar cells. The light acinar cell contains dense secretory granules, whereas dark acinar cells contains granules of medium density with some darker spots within them, or other cells contain granules of medium density with darker rims. 2. Six hours after the irradiation, many acinar cells were degenerated showing variable stages of cytolytic bodies, light bodies, or dense degenerations. Within the acinar cell, Golgi apparatus and granular endoplasmic reticula were most severely altered elements. Granules showed more contrasting densities and irregularities. 3. Two days after the irradiation, some cytolytic bodies, and focal lucent degeneration of cytoplasm, and fine granular alteration of cytoplasmic matrix were pronounced. But other elements including secretory granules are rather looked unlatered. 4. Six days after the irradiation, most severe alterations were seen. Many intracellular canaliculi (or secretion figures), quanta of cytoplasm containing secretion antecedants, severely irregular luminal border, and again contrasting density of secretory granules showing tigroid spots or dense rims were noted. And myoepithelial degenerations were observed not uncommonly. 5. Irregular densities of secretory granules were interpreted as abnormal components of protein or carbohydrate portion are synthesized or abnormally metabolized under severe X-irradiation. 6. Myoepithelial degeneration and related alteration of nerve endings, etc., were suggested as the other causes of xerostomia following X-irradiation. 7. It is requested that radiation doses should be arranged, considering in mind not only the sensitivity of acinar cells but also the myoepithelial and neural functions.

• The Journal of Korean Society for Radiation Therapy
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• v.26 no.2
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• pp.355-362
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• 2014

Purpose : When head&neck cancer radiation therapy, thermoplastic mask is applied for patients with fixed. The purpose of this study is to evaluate usefulness of thermoplastic mask for SRS in tomotherapy by conparison with the conventional mask. Materials and Methods : Typical mask(conventional mask, C-mask) and mask for SRS are used to fix body phantom(rando phantom) on the same iso centerline, then simulation is performed. Tomotherapy plan for orbit and salivary glands is made by treatment planning system(TPS). A thick portion and a thin portion located near the treatment target relative to the mask S-mask are defined as region of interest for surface dose dosimetry. Surface dose variation depending on the type of mask was analyzed by measuring the TPS and EBT film. Results : Surface dose variation due to the type of mask from the TPS is showed in orbit and salivary glands 0.65~2.53 Gy, 0.85~1.84 Gy, respectively. In case of EBT film, -0.2~3.46 Gy, 1.04~3.02 Gy. When applied to the S-mask, in TPS and Gafchromic EBT3 film, substrantially 4.26%, 5.82% showed maximum changing trend, respectively. Conclusion : To apply S-mask for tomotherapy, surface dose is changed, but the amount is insignificant and be useful when treatment target is close critical organs because decrease inter and intra fractional variation.

• KDI Journal of Economic Policy
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• v.14 no.1
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• pp.147-165
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• 1992

This paper analyzes the macroeconomic effects of elections on the Korean economy and their future ramifications. It measures the shocks to the Korean economy caused by elections by taking the average of sample forecast errors from four major elections held in the 1980s. The seven variables' Bayesian Vector Autoregression Model which includes the Monetary Base, Industrial Production, Consumption, Consumer Price, Exports, and Investment is based on the quarterly time series data starting from 1970 and is updated every quarter before forecasts are made for the next quarter. Because of this updating of coefficients, which reflects in part the rapid structural changes of the Korean economy, this study can capture the shock effect of elections, which is not possible when using election dummies with a fixed coefficient model. In past elections, especially the elections held in the 1980s, $M_2$ did not show any particular movement, but the currency and base money increased during the quarter of the election was held and the increment was partly recalled in the next quarter. The liquidity of interest rates as measured by corporate bond yields fell during the quarter the election and then rose in the following quarter, which is somewhat contrary to the general concern that interest rates will increase during election periods. Manufacturing employment fell in the quarter of the election because workers turned into campaigners. This decline in employment combined with voting holiday produce a sizeable decline in industrial production during the quarter in which elections are held, but production catches up in the next quarter and sometimes more than offsets the disruption caused during the election quarter. The major shocks to price occur in the previous quarter, reflecting the expectational effect and the relaxation of government price control before the election when we simulate the impulse responses of the VAR model, imposing the same shocks that was measured in the past elections for each election to be held in 1992 and assuming that the elections in 1992 will affect the economy in the same manner as in the 1980s elections, 1992 is expected to see a sizeable increase in monetary base due to election and prices increase pressure will be amplified substantially. On the other hand, the consumption increase due to election is expected to be relatively small and the production will not decrease. Despite increased liquidity, a large portion of liquidity in circulation being used as election funds will distort the flow of funds and aggravate the fund shortage causing investments in plant and equipment and construction activities to stagnate. These effects will be greatly amplified if elections for the head of local government are going to be held this year. If mayoral and gubernatorial elections are held after National Assembly elections, their effect on prices and investment will be approximately double what they normally will have been have only congressional and presidential elections been held. Even when mayoral and gubernatorial elections are held at the same time as congressional elections, the elections of local government heads are shown to add substantial effects to the economy for the year. The above results are based on the assumption that this year's elections will shock the economy in the same manner as in past elections. However, elections in consecutive quarters do not give the economy a chance to pause and recuperate from past elections. This year's elections may have greater effects on prices and production than shown in the model's simulations because campaigners' return to industry may be delayed. Therefore, we may not see a rapid recall of money after elections. In view of the surge in the monetary base and price escalation in the periods before and after elections, economic management in 1992 should place its first priority on controlling the monetary aggregate, in particular, stabilizing the growth of the monetary base.