• Transactions of the Korean Society of Mechanical Engineers B
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• v.25 no.12
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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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• v.20 no.2
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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.

• Korean Journal of Veterinary Research
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• v.33 no.3
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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.

• Korean Journal of Veterinary Research
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• v.36 no.1
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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.

• Korean Journal of Veterinary Research
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• v.36 no.1
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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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• v.14 no.4
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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.

• Journal of the Korea institute for structural maintenance and inspection
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• v.18 no.3
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• pp.160-166
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• 2014

In this research, as a measure of reducing energy lost through external wall, we used Glass Hollow Micro Sphere (HMS) to improve insulation performance to structural concrete. The following is a result of experimenting concrete using HMS. As usage of HMS, decrease in slump arose and it is judged as a need of using superplasticizer. Replacement ratio increasing more and more, amount of air showed tendency to decrease and compressive strength decreased for interfacial adhesion had not been formed. as replacement ratio and unit volume decreased. It appears that thermal conductivity decreased about 30.0~46.5 percent as compared with normal weight concrete.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.37 no.3
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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.

• The Korean Journal of Nuclear Medicine
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• v.2 no.1
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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.

• Proceedings of the KOR-BRONCHOESO Conference
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• 1979.05a
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• pp.9.3-9
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• 1979

Foreign bodies in air and food passages are not uncommon problems in the otolaryngological fields and its etiological factors are closely related to the social environment and mode of life. It may complicate of esophageal perforation, periesphagitis, periesophageal abscess, mediastinitis, pneumothorax, pyothorax and lung abscess which may lead to the problems of life and death. The majority of esophageal foreign bodies which lodge in the esophagus can be removed endoscopically, but the following types of foreign bodies may require removal by the external route: 1. an impacted foreign body, 2. a foreign body producing periesophagitis after unsuccessful attempts at removal through the esophagoscope, and 3. a periesophageal abscess with a foreign body lodging in the abscess itself. Many interesting cases and statistical analysis of esophageal foreign bodies were reported by many authors, but only a few complicated cases were reported. Recently, we experienced 2 cases of esophageal foreign bodies which penetrate the cervical and thoracic esophageal wall and formed periesophageal abscess in 12 and 40 years-old males who swallowed of wire accidentally. The foreign bodies are successfully removed by the external routes through the lateral neck and chest. The postoperative courses were uneventful.