• Solar Energy
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• v.12 no.3
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• pp.60-69
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• 1992

Heat transfer characteristics and heat storage rate for vertical cylinder packed with paraffin as a latent heat storage material were theoretically studied. Conduction and convection mechanism were applied to the solid and liquid phase, respectively, and the results were compared with that of pure conduction model. The effects of heating temperature, initial solid temperature and aspect ratio on rate of storage were also studied. In the initial stage of melting, the natural convection is nearly restricted by the friction at the wall and the phase boundary. But it is generated when about 40% of solid melts and again it shrinks by the hot liquid situated on the upper part of the cylinder. So overall melting rate is higher then that for pure conduction model. The increase in heating temperature and aspect ratio activates the natural convection, so melting rate becomes higher. And the larger the aspect ratio, the greater the difference between upper and lower size of the solid. In the initial stage of melting, the initial temperature of solid paraffin has great effect on the melting rate, but as melting proceeds its effect lessens gradually.

• Archives of Craniofacial Surgery
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• v.13 no.1
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• pp.22-28
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• 2012

Purpose: In accordance to an increased interest in facial appearance and the popularization of computed tomography scanning, the number of diagnosis and treatment of blowout fractures has been increased. The purpose of this article is to review pure blowout fracture surgery through transconjunctival incision focusing on complications and their management. Methods: In this retrospective study, 583 patients, who had been treated for pure blowout fracture through transconjunctival incision from 2000 to 2009, were evaluated. Their hospital records were reviewed according to their sex, age, fracture site, preoperative presentations, time interval between trauma and surgery, and postoperative complications. Results: According to postoperative follow-up results, there were early complications that included wound dehiscence and infection (0.2%), hematoma (insomuch as extraocular movement is limited) (0.7%), lacriminal duct injury (0.5%), and periorbital nerve injury (0.7%). In addition, there were late complications that lasted more than 6 months, that included persistent diplopia (1.7%), extraocular movement limitation (0.9%), enophthalmos (1.0%), periorbital sensation abnormalities (1.0%), and entropion (0.5%). Conclusion: We propose the following guidelines for prevention of postoperative complications: layer by layer closure; bleeding control with the epinephrine gauzes, Tachocomb, and Tisseel; conjunctival incision 2 to 3 mm away from punctum; avoidance of excessive traction; performing surgical decompression and high dose corticosteroid therapy upon confirmation of nerve injury; atraumatic dissection and insertion of Medpor Barrier implant after securing a clear view of posterior ledge; using Medpor block stacking technique and BioSorb FX screw fixation; performing a complete resection of the anterior ethmoidal nerve during medial wall dissection; and making an incision 2 to 3 mm below the tarsal plate.

• Journal of the Korean Ceramic Society
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• v.55 no.5
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• pp.446-451
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• 2018

In this study, different formulations of magnesium oxide and various modifiers (phosphoric acid, ferrous sulfate, pure acrylic emulsion, silicone acrylic emulsion, glass fiber, and polypropylene fiber) were used to prepare magnesium oxychloride cement composites. The compressive strength of the magnesium oxychloride cement was tested, and the softening coefficients of the composites after soaking in water were also calculated. The results showed that a magnesium oxychloride cement sample could not be coagulated when the MgO activity was 24.3%, but the coagulation effect of the magnesium oxide cement sample was excellent when the MgO activity was 69.5%. While pure acrylic emulsion, silicon-acrylic emulsion, and glass fiber showed insignificant modification effects on the magnesium oxychloride cement, ferrous sulfate heptahydrate, phosphoric acid, and polypropylene fiber could effectively improve its water resistance and compressive strength. When the phosphoric acid, ferrous sulfate heptahydrate, and polypropylene fiber contents were 0.47%, 0.73%, and 0.25%, respectively, the softening coefficient of a composite soaked in water reached 0.93 after 7 days, and the compressive strength reached 64.3 MPa.

• Korean Chemical Engineering Research
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• v.45 no.4
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• pp.351-355
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• 2007

It is necessary to convert butene-2 into butene-1 with higher added-values through positional isomerization. In this study, hydro-isomerization of butene-2 with hydrogen over Pd/alumina catalysts was investigated in a fixed bed reactor. The yield of butene-1 over Ld-265 catalyst was higher than that over other catalysts. The yield of butene-1 was highest (5.3%) under the conditions of reaction temperature of $75^{\circ}C$, reaction pressure of 150 psig, 2-butene flow rate of 48 cc/h and hydrogen flow rate of 3 cc/min. We conducted simulation for the process composed of a hydro-isomerization reactor and a distillation tower. In the case of 78% of tray efficiency, we obtained over 99% pure butene-1 through a distillation tower with 171 steps (R=120).

• Clinical and Experimental Reproductive Medicine
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• v.13 no.2
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• pp.153-159
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• 1986

The high rate of chromosomal abnormalities in patients with primary amenorrhea implies the need for routine screening for chromosomal abnormalities among such patients. This study was designed for the cytogenetic analysis of 236 patients with primary amenorrhea, which was referred to Yonsei University Medical Center, from January, 1, 1974 to December, 31, 1985. The results were as follows: 1. Of the 236 patients, 145 cases (61.4%) showed normal karyotype, and 91 cases (38.6%) showed chromosomal abnormalities. 2. Gonadal dysgenesis was found in 56 cases, consisting of 42 cases, Turner's syndrome, 12 cases, pure gonadal dysgenesis, and 2 cases mixed gonadal dysgenesis. a) Turner's syndrome was found in 42 cases, consisting of 18 cases of 45, X and 24 cases of mosaicism. b) Pure gonadal dysgenesis was found in 12 cases, consisting of 10 cases of 46, XX and 2 cases of 46, XY. c) Mixed gonadal dysgenesis was found in 2 cases, consisting of 1 case of 46, XY and 1 case of 45, X/46, XY. 3. Intersex was found in 80 cases, consisting of 35 cases of 46, XX, and 45 cases of 46, XY. 4. Congenital anomalies of reproductive system was found in 82 cases and all cases were normal karyotype.

• The Journal of Advanced Prosthodontics
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• v.1 no.1
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• pp.41-46
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• 2009

STATEMENT OF PROBLEM. The poor chemical bonding of a denture base resin to cast titanium framework often introduces adhesive failure and increases microleakage. PURPOSE. This study evaluated the shear bond strengths of a heat cure denture base resin to commercially pure titanium, Ti-6Al-4V alloy and a cobalt-chromium alloy using two adhesive primers. MATERIAL AND MATHODS. Disks of commercially pure titanium, Ti-6Al-4V alloy and a cobalt-chromium alloy were cast. Specimens without the primer were also prepared and used as the controls. The shear bond strengths were measured on a screw-driven universal testing machine. RESULTS. The primers significantly(P < .05) improved the shear bond strengths of the heat cure resin to all metals. However, the specimens primed with the Alloy $primer^{(R)}$(MDP monomer) showed higher bond strength than those primed with the MR $bond^{(R)}$(MAC-10 monomer) on titanium. Only adhesive failure was observed at the metal-resin interface in the non-primed specimens, while the primed specimens showed mixed failure of adhesive and cohesive failure. CONCLUSIONS. The use of appropriate adhesive metal primers makes it possible not only to eliminate the need for surface preparation of the metal framework before applying the heat cure resins, but also reduce the need for retentive devices on the metal substructure. In particular, the Alloy $primer^{(R)}$, which contains the phosphoric acid monomer, MDP, might be clinically more acceptable for bonding a heat cure resin to titanium than a MR $bond^{(R)}$, which contains the carboxylic acid monomer, MAC-10.

• Journal of the Korea Concrete Institute
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• v.26 no.6
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• pp.771-778
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• 2014

This paper concerns the flexural behavior of hybrid steel fiber-reinforced ultra high performance concrete (UHPC) beams. It presents experimental research results of hybrid steel fiber-reinforced UHPC with steel fiber content of 1.5% by volume and steel reinforcement ratio of less than 0.02. This study aims at providing realistic information about UHPC beams in bending in order to establish a reasonable prediction model for flexural resistance in structural code in the future. The experimental results show that hybrid steel fiber-reinforced UHPC is in favor of cracking resistance and ductility of beams. The ductility indices range through 9.2 to 15.2, which means high ductility of UHPC. Also, the flexural capacity of beam which contains stirrups in pure bending zone is similar to that of beam which does not contain stirrups in pure bending zone. This result represents that the flexural capacity is not affected by the presence of stirrups whose spacing is 150 mm in bending zone.

• The Journal of Korean Medicine
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• v.44 no.4
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• pp.121-135
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• 2023

Objectives: This study aimed to establish and provide reliable information for general public, based on expert consensus, on the risks of misuse of medicinal herbs for food and pure food ingredients for the fetus during pregnancy. Methods: A panelist of seven traditional Korean medicine (TKM) gynecologists responded to a questionnaire summarizing the fetal safety literature for twenty-five medicinal herbs for food and pure food ingredients derived from medicated diet (藥膳, Yaksun) recipes during three online Delphi rounds anonymously. Results: Ginkgonis Semen (Ginkgo nut), Illici Veri Fructus (Star anise), lavender, bitter gourd, and parsley were agreed at the level 1 of "Do not consume". These five ingredients were recognized as having significant risks both in the literature evidence and in expert opinion. Rosemary, Citri Unshius Pericarpium, Discoreae Rhizoma, lemongrass, Schisandrae Fructus, Cassiae Semen, Foeniculi Fructus, Mori Fructus, Cinnamomi Cortex, and Astragali Radix were agreed at the level 2 of "consultation with TKM practitioner is required". Conclusion: Based on the consensus of a seven-member expert panel of TKM gynecologists, consumption of Ginkgonis Semen (Ginkgo nut), Illici Veri Fructus (Star anise), lavender, bitter gourd, and parsley should be avoided by pregnant women. For Rosemary, Citri Unshius Pericarpium, Discoreae Rhizoma, lemongrass, Schisandrae Fructus, Cassiae Semen, Foeniculi Fructus, Mori Fructus, Cinnamomi Cortex, and Astragali Radix, the level 2 advisory may be recommended to use with caution and to consult a TKM practitioner for advice on consumption, dose, and duration.

• Journal of Korean Philosophical Society
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• v.131
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• pp.165-197
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• 2014

In this paper, I investigate on the human nature in philosophy of Wang Yang-Ming and Buddhism from a Kantian point of view. The core argument of the philosophy of Wang Yang-Ming, Buddhism and Kant is that all human beings have the pure abilities a priori to overcome themselves, to realize their own potentialities. This is called immanent transcendence. At this time human beings can be free. Kant, Wang Yang-Ming and Buddhism claim that all human beings themselves will overcome their desires from their mind and body through the immanent transcendence, reflection and contemplation on their own. When we give up the external knowledges, throw away obsessions with the selfish desires and go back to our inside, we can see our original nature. To have an insight into this inner nature, to respect the moral law a priori, this is to overcome the ourselves, and to be a Grate Man(聖人) and a Buddha. This way is the only way to be a Grate Man and a Buddha. The main proposition of Wang Yang-Ming's philosophy is expressed 'There are no things without mind.'(心外無物) The core of Kant's transcendental philosophy is called the Copernican Revolution by himself. Copernican Revolution means the transition from the object-centered epistemology to the subject-centered epistemology. 'Innate Knowing'(良知) and 'Perform Innate Knowing'(致良知), 'All human beings have the mind of Buddha'(一切衆生悉有佛性) contain the apriority, immanence of Moral Law. In this respect, the theory of Innate Knowing in Wang Yang-Ming and mind of Buddha in Buddhism, pure Moral Law in Kant has the same structure grounded in subjectivity. Even if we have the mind of Buddha, innate Knowing, moral law a priori, the reason why we don't know our original nature is that we fall into the obsessions with selfish desires, and that we have inclination to external interests. So the moment you see our original nature, ordinary people themselves turn into a Buddha. These changes and transitions are immanent transcendence. All human beings have the ability to do this changes and transitions. Buddha does not exist outside of us, but it exists with our reflections on our human nature. Buddha can not existed without our insight into the our innate Ego. Where there is our original nature, there is a Buddha. So Buddha is called the another name of the original figure of human beings.

• The Journal of Korean Society for Radiation Therapy
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• v.31 no.1
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• pp.57-65
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• 2019

Purpose: The purpose is to clarify the effect of additional scattering ratio on the edge of the block according to the increasing block thickness with low melting point lead alloy and pure lead in electron beam therapy. Methods and materials: $10{\times}10cm^2$ Shielding blocks made of low melting point lead alloy and pure lead were fabricated to shield mold frame half of applicator. Block thickness was 3, 5, 10, 15, 20 (mm) for each material. The common irradiation conditions were set at 6 MeV energy, 300 MU / Min dose rate, gantry angle of $0^{\circ}$, and dose of 100 MU. The relative scattering ratio with increasing block thickness was measured with a parallel plate type ion chamber(Exradin P11) and phantom(RW3) by varying the position of the shielding block(cone and on the phantom), the position of the measuring point(surface ans depth of $D_{max}$), and the block material(lead alloy and pure lead). Results : When (depth of measurement / block position / block material) was (surface / applicator / pure lead), the relative value(scattering ratio) was 15.33 nC(+0.33 %), 15.28 nC(0 %), 15.08 nC(-1.31 %), 15.05 nC(-1.51 %), 15.07 nC(-1.37 %) as the block thickness increased in order of 3, 5, 10, 15, 20 (mm) respectively. When it was (surface / applicator / alloy lead), the relative value(scattering ratio) was 15.19 nC(-0.59 %), 15.25 nC(-0.20 %), 15.15 nC(-0.85 %), 14.96 nC(-2.09 %), 15.15 nC(-0.85 %) respectively. When it was (surface / phantom / pure lead), the relative value(scattering ratio) was 15.62 nC(+2.23 %), 15.59 nC(+2.03 %), 15.53 nC(+1.67 %), 15.48 nC(+1.31 %), 15.34 nC(+0.39 %) respectively. When it was (surface / phantom / alloy lead), the relative value(scattering ratio) was 15.56 nC(+1.83 %), 15.55 nC(+1.77 %), 15.51 nC(+1.51 %), 15.42 nC(+0.92 %), 15.39 nC(+0.72 %) respectively. When it was (depth of $D_{max}$ / applicator / pure lead), the relative value(scattering ratio) was 16.70 nC(-10.87 %), 16.84 nC(-10.12 %), 16.72 nC(-10.78 %), 16.88 nC(-9.93 %), 16.90 nC(-9.82 %) respectively. When it was (depth of $D_{max}$ / applicator / alloy lead), the relative value(scattering ratio) was 16.83 nC(-10.19 %), 17.12 nC(-8.64 %), 16.89 nC(-9.87 %), 16.77 nC(-10.51 %), 16.52 nC(-11.85 %) respectively. When it was (depth of $D_{max}$ / phantom / pure lead), the relative value(scattering ratio) was 17.41 nC(-7.10 %), 17.45 nC(-6.88 %), 17.34 nC(-7.47 %), 17.42 nC(-7.04 %), 17.25 nC(-7.95 %) respectively. When it was (depth of $D_{max}$ / phantom / alloy lead), the relative value(scattering ratio) was 17.45 nC(-6.88 %), 17.44 nC(-6.94 %), 17.47 nC(-6.78 %), 17.43 nC(-6.99 %), 17.35 nC(-7.42 %) respectively. Conclusions: When performing electron therapy using a shielding block, the block position should be inserted applicator rather than the patient's body surface. The block thickness should be made to the minimum appropriate shielding thickness of each corresponding using energy. Also it is useful that the treatment should be performed considering the influence of scattering dose varying with distance from the edge of block.