• 대한기계학회논문집B
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• 제25권12호
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• pp.1831-1843
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• 2001

In this study, convective boiling tests were conducted for enhanced tube bundles. The surface geometry consists of pores and connecting gaps. Tubes with three different pore sizes (d$_{p}$ = 0.20, 0.23 and 0.27 mm) were tested using R-123 and R-l34a for the following range: 8 kg/m$^2$s G 26 kg/m$^2$s, 10 kW/m$^2$ q0 40 kW/m$^2$and 0.1 $\chi$ 0.9. The convective boiling heat transfer coefficients were strongly dependent on heat flux with negligible dependency on mass flux or quality. For the present enhanced geometry (pores and gaps), the convective effect was apparent. The gaps of the present tubes may have served routes for the passage of two-phase mixtures, and enhanced the boiling heat transfer. The convective effect was more pronounced at a higher saturation temperature. More bubbles will be generated at a higher saturation temperature, which will lead to enhanced convective contribution. The pore size where the maximum heat transfer coefficient was obtained was larger for R-l34a (d$_{p}$ = 0.27 mm) compared with that for R-123 (d$_{p}$ = 0.23 mm). This trend was consistent with the previous pool boiling results. For the enhanced tube bundles, the convective effect was more pronounced for R-134a than for R-123. This trend was reversed for the smooth tube bundle. Possible reasoning is provided based on the bubble behavior on the tube wall. Both the modified Chen and the asymptotic model predicted the present data reasonably well. The RMSEs were 14.3% for the modified Chen model and 12.7% for the asymptotic model.model.

• The Plant Pathology Journal
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• 제20권2호
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• pp.81-84
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• 2004

Branched broomrape (Orobanche ramosa) is a holo-parasitic flowering plant that attaches to the root of its host, green plant, by means of a specialized structure known as haustorium. Following successful contact and penetration on susceptible plant root, complex tissue of Orobanche cells is formed which is known as the tubercle. Newly formed tubercles contain high activity ofindole-3-acetic acid (IAA). Triiodobenzoic acid (TIBA), as an inhibitor of IAA polar transport, was utilized to investigate the supply and requirement of auxin to the developing O. ramosa on tomato plant. There was no significant reduction in the incidence of O. ramosa per pot of different TIBA treatments. However, infection severity in terms of the number of O. ramosa shoots that emerged per plant and number of attachments per plant root system were significantly reduced by 60 % and 45 % on TIBA treated plants, respectively. Histo-logical studies revealed conspicuous delay in the initiation of xylem vessel differentiation inside tubercles of the TIBA treated tomato plants. Also, differentiated vessels showed thinner secondary wall deposition, and improper alignment within bundles inside those tubercles. They were wider and shorter in diameter in comparison to those of untreated plants. These findings were attri-buted to the short supply of IAA required for normal development, and to the xylem vessel differentiation of O. ramosa tubercles on infected tomato. Hence, this parasitic flowering plant seems to depend upon its host in its requirements for IAA, in a source to sink relation-ship.

• 대한수의학회지
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• 제33권3호
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• pp.493-505
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• 1993

Present experiments were undertaken in order to clarify the clinico-pathological characteristics of lead poisoning in goats. Twenty goats were divided into three experimental groups(A, B and C) and a control(D). The three experimental groups received diets contaminated artificially with 10(A group), 200(B group) and $1,000(C group){\mu}g/g$ of lead for 70 days, respectively. The control group received normal diets. Hair samples collected one or two weeks interval were examed for the lead content. On day 70. all the animals were necropsied and various organs were examined pathoanatomically. In addition, various organs were analyzed for lead, zine, copper, iron and calcium content by atomic absorption spectrophotometry. From these experiments following results were obtained ; The lead content of hair was significantly increased from the $42^{nd}$, $21^{st}$ or $14^{th}$ day in all the three groups, which showed significant correlation with lead content of liver and spleen. The lead content of various organs including kidney, liver, spleen, ileum, bone and abomasum were significantly increased in accordance with the lead contamination. The increase was most prominent in abomasal wall. The zinc and copper content of liver, brain, ileum, skin, kidney, lung or muscle were increased in B and C groups whereas the iron and calcium content showed no significant change. Pathoanatomically, degeneration or necrosis of proximal convoluted tubules of kidney, peripheral necrosis of liver, fundic gland necrosis of abomasum and cerebral edema were observed in B and C groups.

• 대한수의학회지
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• 제36권1호
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• pp.235-245
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• 1996

Serial ultrasonographic examinations were performed on 9 pregnant Korea Jin-do bitches that were the Korean native breed, from days 15 to 60 pregnancy to determine the time of first detection and ultrasonographic appearance of the fetal and extra-fetal structures of pregnancy. Gestational age was timed from the day of ovulation (Day 0), which was estimated to occur when plasma progesterone concentration was first increased above 4.0 ng/ml. Gestational ages at earliest detection of the following fetal and extra-fetal structures were; gestational sac at days 17 to 22; placental layers in the uterine wall at days 20 to 24; zonary placenta at days 25 to 28; yolk sac membrane at days 22 to 24; amnionic membrane at days 27 to 29; embryo initial detection at days 21 to 23; fetal heartbeat at days 21 m 25; bipolar shape embryo at days 25 to 26; fetal movement at days 28 to 31; limb buds at days 31 to 35; anechoic area in head at days 31 to 36; stomach at days 34 to 37; urinary bladder at days 34 to 37; skeleton at days 36 to 38; dorsal sagittal tubular structure in vertebrae at days 36 to 38; lung hyperechoic vs liver at days 37 to 39; liver hypoechoic vs abdomen at days 37 to 40 and kidney at days 43 to 48, respectively.

• 대한수의학회지
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• 제36권1호
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• pp.101-108
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• 1996

This study was desinged to investigate the effect of estrogen(Est) on the proliferating of progesterone(Prog) target cells. The spayed 13 rats(Wistar, approximately 300gm) were randomly alloted into 3 groups. One group was the control group and another Prog-treated group was injected with 1mg of Prog/rat/day for 2 consecutive days, and Estand Prog-treated group was injected intramuscularly with $17{\beta}$-estradiol $20{\mu}g/rat/day$ for 3 consecutive days and then with Prog for 2 days as above from 4th day. Rats were administrated intraperitoneally with bromodeoxyuridinc(Brdur,0.2mg/BW once) befero 2 hours of exanguination. In gross finding, the groups with more level of dimension and weight on the uterus were ordered as Est- and Prog-treated group, Prog-treated group and control group. The investigation by immunohistochemical methods using paraffin sections of the uteri was performed by using anti-Brdur antibody for labeling proliferating cells of Prog target cells. The groups with higher labeling index(LI) were ordered as Prog-treated grop, Est- and Prog- treated group and control group. The number of proliferating cells from Prog target cells in the rats were rather deceased by Prog injection following Est injection than prog injection only. The cell types with higher LI in the wall layers of all 3 groups were ordered as endometrial stromal cells, glandular epithelial cells, luminal epithelial cells, myometrial muscle cells and serosa methodelial cells, and the region with highest LI was functional zone of the endometrium and the region with lower LI was muscular layer and then those with lowest LI was serosa and also the considerable different LI from individual rat were observed.

• Journal of Biosystems Engineering
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• 제14권4호
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• pp.272-281
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• 1989

It is desirable for the vertical wind tunnel which can build uniform air flow across the vertical duct to be used for the purpose of the investigation of the aerodynamic properties of grains. This study was conducted to examine how the air velocity profile in the vertical duct is influenced by the various alternations of the elements of the wind tunnel, and to prepare design guidance of the vertical wind tunnel which can be used for investigating aerodynamic properties of grains. In addition, several tests were conducted to locate the test section which can be applicable for determining the terminal velocity of grain. The following conclusions were obtained from the study: 1. The size and the location of the outlet of the plenum chamber should be determined such that the outlet air flow is less affected by the air flow and the back pressure by the side wall of the chamber. 2. The honeycomb was not helpful for attaining uniform air flow in case that the air flow profile at the bottom of the vertical duct is serverely different from the ideal one. 3. Even though considerable pressure drop was resulted from the screens installed within the vertical duct, the screens were helpful for attaining uniform air flow in the duct. 4. It is desirable for the test section to be located at the position that not only the air flow of the duct is not disturbed by the distorted back pressure in the plenum chamber, but also less boundary layer is developed.

• 한국구조물진단유지관리공학회 논문집
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• 제18권3호
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• pp.160-166
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• 2014

본 연구에서는 건축물의 외피를 통해 손실되는 냉난방 에너지를 감소시킬 수 있는 방안으로써, 구조용 콘크리트에 단열성능을 향상시킬 수 있는 할로마이크로스피어 (Hollow Micro Sphere, 이하 HMS)를 사용하였다. 중공구조의 마이크로 크기의 입자인 HMS를 사용한 콘크리트를 실험한 결과는 아래와 같다. HMS의 사용으로 인해 슬럼프에 감소가 나타나 고성능감수제의 사용이 필요할 것으로 판단된다. 공기량은 HMS의 치환율이 증가할수록 감소하는 경향을 보였으며, 압축강도는 HMS의 계면부착력이 형성되지 않는 것에 기인하여 치환율 증가에 따라 감소하는 것으로 나타났다. 열전도율과 단위용적질량은 치환율이 증가할수록 감소하였다. 열전도율은 보통콘크리트 약 30.0~46.5% 감소한 것으로 나타났다.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제37권3호
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• pp.237-240
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• 2011

Epidermoid cysts presents as a nodular and fluctuant subcutaneous lesion beneath the skin and are most common in acne-prone areas of the head, neck and back. This cyst often arises after localized inflammation of the hair follicle and occasionally after the implantation of epithelium following trauma and surgery including a biopsy procedure. It is often associated with Gardner syndrome, particularly before puberty. The lesion is normally treated by a surgical excision or enucleation, and recurrence is uncommon. A 27 year old woman complained of a swelling of the left parotid gland when she visited our clinic. A cystic lesion was found in the left parotid gland from the high signal intensity on the MR images. Ultrasonography showed that the cystic lesion was heterogeneous echogenic. Six months earlier, botulinum toxin was injected in her left masseter muscles six months earlier and progressive swelling of the left parotid area was noticed four months after treatment. The lesion was surgically removed. It was encapsulated by a thin wall and filled mainly with keratin. The final diagnosis was an epidermoid cyst.

• 대한핵의학회지
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• 제2권1호
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• pp.43-48
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• 1968

A comparative study of $^{131}I$-hippuran renogram, $^{131}I$-hippuran excretion test and intravenous pyelogram were performed in 61 cases of gynecological cancer. The following were the results: 1. Among 40 cases of cervix cancer showing normal excretory urography 7 cases (17.5%) were found to have unilateral or bilateral delayed excretory pattern on $^{131}I$-hippuran renogram and on the contrary only 2 cases (5.7%) showed a mild caliectatic change on excretory urography among 35 cases of gynecological cancer showing normal pattern of $^{131}I$-hippuran renogram. 2. In the group showing unilateral or bilateral delayed excretory pattern on $^{131}I$-hippuran renogram there was a reduction of $^{131}I$-hippuran excretion in the first 20 minutes, but there was no significant difference of $^{131}I$-hippuran excretion in 60 minutes compared with that of normal renogram group. 3. In the group showing unilateral non-functioning pattern of $^{131}I$-hippuran renogram in one side and normal pattern in the other side there was found to be no difference in $^{131}I$-hippuran excretion amount compared with that of normal renogram group. 4. It was evident from these experimental study that $^{131}I$-hippuran renogram was considered as a good examination method for the evaluation of obstructive uropathy, and if one side kidney was intact it might compensate for the other diseased kidney so far as to renal excretory function. It was also shown that the more severe the cancerous spread in the pelvic wall the more changes on $^{131}I$-hippuran renogram.

• 대한기관식도과학회:학술대회논문집
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• 대한기관식도과학회 1979년도 제13차 학술대회 연제순서 및 초록
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• pp.9.3-9
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• 1979

식도이물은 기도이물과 더불어 이비인후과영역에서 흔히 불 수 있는 질환으로서 그 발생동기가 환경 및 생활양식과 밀접한 관계가 있고 때로는 식도천공, 식도주위염, 식도주의농양, 종격동염, 기흉, 농흉 및 폐농양등의 중독한 합병증을 일으켜 생명에 위험을 초래하는 예도 적지 않다. 대부분의 식도이물은 식도경하에서 적출이 가능하지만, 이물이 식도내에 머물러 있으나 육아조직이 포위하여 식도경으로서 적출이 불가능 하든가 또는 이물이 식도벽을 뚫고 나가 형성한 농양내에 이물이 있을 매는 외과적수술에 의하여 경부나 흉부로 부터 들어가서 적출할 수 밖에 없다. 지금까지 국내외에서 식도이물에 관한 흥미로운 예나 그 종류 및 빈도에 대한 통계보고는 많았으나 이물자체로 인한 또 그 치료후에 발생한 합병증에 관한 보고는 별로 많지 않았다. 최근 저자들은 12재 남아에서 예리한 철사가 경부식도를 뚫고 나가 식도주위농양을 형성한 예와 40세 남자에서 음식물에 섞인 철사를 오연한 후 철사가 흉부식도를 뚫고 나가 식주위농양을 형성한 예를 각각 경부 및 흉부를 통한 외과적수술에 의하여 성공적으로 적출하여 완치시켰기에 문헌고찰과 함께 보고하는 바이다.