• International Journal of Air-Conditioning and Refrigeration
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• v.14 no.2
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• pp.49-56
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• 2006

Heat transfer performances of individual row of two-row fin and tube heat exchangers are experimentally investigated. Tested are four heat exchangers which are geometrically identical with the exception of fin shape, slit or louver, and that the fins between the first row and the second row are connected or separated. The tube diameter and fin spacing of the heat exchangers examined are 7mm and 1.4mm, respectively. All thermal fluid measurements are made using a psychrometric calorimeter. In order to evaluate air-side heat transfer coefficients of individual rows, tube-side water flow rates of individual rows are independently controlled such that the water-side temperature drops in each row remain at $5^{\circ}C$. Frontal air velocity varies in the range from 0.7m/s to 2.5m/s. Heat transfer coefficients are presented in terms of Colburn ${\jmath}-factor$. The results show that the heat transfer coefficient of the upstream row is larger than that for the downstream row at low Reynolds numbers.

• Journal of the Korean Wood Science and Technology
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• v.30 no.3
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• pp.18-25
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• 2002

Research to discuss the fire performance of materials requires tools for measuring their burning characteristics and validated fire growth models to predict fire behavior of the materials under specific tire scenarios using the measured properties as input for the models. In this study, burning characteristics such as time to ignition, weight loss rate, flame spread, heat release rate, total heat evolved, and effective heat of combustion for four types of wood-based materials were evaluated using the cone calorimeter and inclined panel tests. Time to ignition was affected by not only surface condition and specific gravity of the tested materials but also the type and magnitude of heat source. Results of weight loss rate, measured by inclined panel tests, indicated that heat transfer from the contacted flame used as the heat source into the inner part of the specimen was inversely proportional to specific gravity of material. Flame spread was closely related with ignition time at the near part of burning zone. Under constant and severe external heat flux, there was little difference in weight loss rate and total heat evolved between four types of wood-based panels. More applied heat flux caused by longer ignition time induced a higher first peak value of heat release rate. Burning characteristics data measured in this study can be used effectively as input for fire growth models to predict the fire behavior of materials under specific fire scenarios.

• Asian-Australasian Journal of Animal Sciences
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• v.5 no.3
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• pp.435-438
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• 1992

Data were collected on productive and reproductive performance of different $F_1$ crossbred cows (Deshi cows joined by A.I. to Sindhi, Sahiwal, Jersey or Holstein-Friesian Bull semen) reared by farmers in and around the Bangladesh Agricultural University campus at Mymensingh. The traits considered were birth weight, age at first heat, age at first calving, gestation length, post-partum heat period, milk yield, lactation length, dry period and calving interval. Data were analyzed statistically using a completely randomized design and Duncan's Multiple Range Test to compare and determine the significance of between individual group means. It was observed that the Holstein $\times$ Deshi had the highest birth weight (21.4 kg) followed by Sahiwal (17.6 kg), Jersey (16.7 kg) and Sindhi (16.1 kg). Shortest age at first heat (854 and 920 days) and age at first calving (1002 and 1201 days) were found for the Jersey $\times$ Deshi and Holstein $\times$ Deshi crosses respectively. The post-partum heat period were significantly different between breeds with Jersey and Holstein sired calves having the shortest intervals. There was no difference in the gestation length of the four crosses. Holstein $\times$ Deshi and Jersey $\times$ Deshi cows gave the highest milk yields due to longer lactation periods and higher daily milk production. Similarly, Holstein $\times$ Deshi and Jersey $\times$ Deshi crosses had significantly shorter dry periods and Jersey $\times$ Deshi had a shorter calving interval. From this study it may be concluded that exotic genotypes such as Holstein-Friesian and Jersey can perform very well under rural conditions in Bangladesh.

• Journal of Periodontal and Implant Science
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• v.52 no.5
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• pp.411-421
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• 2022

Purpose: In this study, we aimed to evaluate the degree of heat generation when a novel drill design with an irrigation slot was used with metal sleeve-free (MF) and metal sleeve-incorporated (MI) surgical guides in an environment similar to that of the actual oral cavity. Methods: A typodont with a missing mandibular right first molar and 21 bovine rib blocks were used. Three-dimensional-printed MF and MI surgical guides, designed for the placement of internal tapered implant fixtures, were used with slot and non-slot drills. The following groups were compared: group 1, MI surgical guide with slot drill; group 2, MI surgical guide with a non-slot drill; and group 3, MF surgical guide with a slot drill. A constant-temperature water bath at 36℃ was used. The drilling was performed in 6 stages, and the initial, highest, and lowest temperatures of the cortical bone were measured at each stage using a non-contact infrared thermometer. Results: There were no temperature increases above the initial temperature in any drilling procedure. The only significant difference between the non-slot and slot groups was observed with the use of the first drill in the MI group, with a higher temperature in the non-slot group (P=0.012). When the heat generation during the first and the second drilling was compared in the non-slot group, the heat generation during the first drilling was significantly higher (P<0.001), and there was no significant difference in heat generation between the drills in the slot group. Conclusions: Within the limitations of this study, implant-site preparation with the surgical guide showed no critical increase in the temperature of the cortical bone, regardless of whether there was a slot in the drill. In particular, the slotted drill had a cooling effect during the initial drilling.

• Women's Health Nursing
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• v.7 no.4
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• pp.610-621
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• 2001

In order to find out whether Hand Acupuncture Therapy and Moxibustion Heat Therapy is effective to relieve dysmenorrhea syndrome, we performed a Quasi-experiment on a group of fourty females. The experiment was carried out during the period from April 20 to August 20, 1999. The group was divided into two sub-groups called "a Hand Acupuncture Therapy sub-group" and "a Moxibustion Heat Therapy sub-group" consisting of 20 females respectively. Hand Acupuncture Therapy and Moxibustion Heat Therapy were performed four times a week. Especially, in case of Moxibustion Heat Therapy, subjects were treated twice a times. The data analyzed by an SAS program. The results are as follows : 1) Hand Acupuncture Therapy and Moxibustion Heat Therapy are very effective to relieve dysmenorrhea syndrome. This study shows that in case of Hand Acupuncture Therapy sub-group, supposing that mean score of Menorrhalgia before treatment was 7.85, it became low to 4.50 when. subjects suffered the first menstruation and it was 2.50 at the second menstruation, and 1.60 at the third menstruation. In the mean score of Moxibustion Heat Therapy sub-group, Menorrhalgia before treatment was 7.85, it was 5.90 at the first menstruation(p<.05), and 3.00 at the second, and 1.85 at the third menstruation. 2) Among Hand Acupuncture Therapy subgroup, 9 subjects could hardly be relieved from the pain of dysmenorrhea at the first menstruation. So, they were treated additionally with the method of tonification and sedation of abdominal diagnosis of three constitution and became completely relieved at second menstruation. Meanwhile, 7 subjects among Moxibustion Heat Therapy also faced the same situation. So they were treated with Moxibustion on dorsum of hand and got effectiveness at the third menstruation after taking therapy. 3) Odinary dysmenorrhea syndrome are constipation, dizziness, anorexia, abdominal pain, lumbago, breast engorgement, abdominal distention, dysconcentration, nervousness, diarrhea, nausea & vomitting, apathy, restlessness, fatigue, aggression, leg pain, edema. After taking therapy, all of subjects were relieved from these dysmenorrhea syndrome at third menstruation. 4) All subjects were classified into five types of physical constitution with abdominal diagnosis of three constitution as follows: 18 cases of left kidney right yang excess, 8 cases of left yin right yang excess, 7 cases of left right kidney excess, 5 cases of left right yang excess, 2 cases of left yang right kidney excess.

• Journal of the Korean Ceramic Society
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• v.45 no.12
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• pp.845-850
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• 2008

Hydrated sodium silicate was synthesized by hydrothermal reaction using anhydrous sodium silicate. The optimum additions of water was 25wt% to make hydrated sodium silicate with homogeneous and purposed water contents. Porous ceramics with homogeneous microstructure and spherical closed pore can be fabricated by elimination of the large pores(a few mm in size) which was formed during first heat treatment through the decomposition of water. Spherical closed pore was formed above $600^{\circ}C$ and the pore size was increased with increasing second heat treatment temperature due to growth of pores. The size of spherical closed pore was varied from 35 to $233\;{\mu}m$ and specific gravity was varied from 0.2 to 1.02 depending on the combinations of the first and second heat treatment temperature.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.32 no.11
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• pp.1016-1021
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• 2008

The development of the first wall whose major function is to withstand high neutron and heat fluxes is a critical path to fusion power. The materials database and the fabrication technology are being developed for design, construction and safety operation of the fusion reactor. The first wall was designed to consist of the plasma facing armor, the heat sink layer and the supporting plates. and Porous materials are of significant interest due to their wide applications in catalysis, separation, lightweight structural materials. In this study, the characteristics of the sintering process of SiC ceramic, $SiC_f$/SiC composite and porous $C_f$/SiC composite have been introduced order to study of the fusion blanket materials and heat-exchange pannel.

• Journal of the Korean Solar Energy Society
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• v.27 no.4
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• pp.87-95
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• 2007

Thermodynamic analysis of water-to-water heat pump system based on the first and second law of thermodynamics is carried out in this study. This analysis shows the distribution of irreversibilities throughout the system components and informs us of a potential improvements with the temperature condition changes. Source water temperature($T_A$), utilization water temperature($T_D$) and temperature differences (${\Delta}T_{AB}$, ${\Delta}T_{CD}$) are important factors to affect system performances such as component irreversibilities, exergetic efficiency and COPH. Advantages and disadvantages with these factors are discussed. Second law optimization phenomena with $T_A$ and ${\Delta}T_{AB}$ are also indicated.

• Bulletin of the Society of Naval Architects of Korea
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• v.19 no.4
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• pp.19-29
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• 1982

Galerkin's finite element method is applied to a two-dimensional heat convection-diffusion problem arising in the hydrodynamic lubrication of thrust bearings used in naval vessels. A parabolized thermal energy equation for the lubricant, and thermal diffusion equations for both bearing pad and the collar are treated together, with proper juncture conditions on the interface boundaries. it has been known that a numerical instability arises when the classical Galerkin's method, which is equivalent to a centered difference approximation, is applied to a parabolic-type partial differential equation. Probably the simplest remedy for this instability is to use a one-sided finite difference formula for the first derivative term in the finite difference method. However, in the present coupled heat convection-diffusion problem in which the governing equation is parabolized in a subdomain(Lubricant), uniformly stable numerical solutions for a wide range of the Peclet number are obtained in the numerical test based on Galerkin's classical finite element method. In the present numerical convergence errors in several error norms are presented in the first model problem. Additional numerical results for a more realistic bearing lubrication problem are presented for a second numerical model.

• Journal of Sasang Constitutional Medicine
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• v.27 no.1
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• pp.57-70
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• 2015

Objectives This research was performed to present Clinical Practice Guideline(CPG) for Taeeumin Disease of Sasang Constitutional Medicine(SCM): Liver Heat-based Interior Heat (Gansuyeol-liyeol) disease. This CPG was developed by the national-wide experts committee consisting of SCM professors. Methods First, it was performed that search and collection of literature related to SCM such as "Dongeuisusebowon", Textbook of SCM, Clinical Guidebook of SCM and fundamental researches to standardize the diagnosis of Sasang Constitutional Medicine. And journal search related to clinical trials and case studies concerning SCM was performed domestic and overseas. Finally, 12 articles were selected and included in CPG for Liver Heat-based Interior Heat (Gansuyeol-liyeol) disease in Taeeumin Disease. Experts consensus was drawn through several meetings. Results & Conclusions CPG of Liver Heat-based Interior Heat (Gansuyeol-liyeol) disease in Taeeumin Disease include classification, definition and standard symptoms of each pattern. Liver Heat-based Interior Heat (Gansuyeol-liyeol) disease is classified into Liver-Heat (Ganyeol) symptomatology and Liver-Heat Lung-Dry (Ganyeol-paeJo) symptomatology. Depending on the severity of Liver Heat, Liver-Heat (Ganyeol) symptomatology is classified into mild pattern and moderate pattern. Mild pattern contains 1 disease, namely, Liver-Heat (Ganyeol) initial pattern. Moderate pattern classified into advanced pattern and intense pattern. Depending on the severity of the Lung-Dry, Liver-Heat Lung-Dry (Ganyeol-paeJo) symptomatology is classified into severe pattern and critical pattern. Severe pattern is classified into Dry-Heat (Joyeol) pattern and Dry-Heat (Joyeol) advanced pattern. Critical pattern contains 1 disease, namely, Dry-Heat (Joyeol) intense pattern (Eumhyeol-mogal yeolda pattern).