Optimization of phase change materials to improve energy performance within thermal comfort range in the South Korean climate

Park, Ji Hun,Lee, Jongki,Wi, Seunghwan,Jeon, Jisoo,Chang, Seong Jin,Chang, Jae D.,Kim, Sumin Elsevier 2019 Energy and buildings Vol.185 No.-

<P><B>Abstract</B></P> <P>Worldwide growth and the pursuit of comfort in buildings have led to significant increase in energy consumption, which is considered a current issue. Phase change material (PCM), a thermal energy storage (TES) material, is considered an effective and promising material to reduce energy consumption. In recent years, research on the application of PCM to provide higher comfort for occupants has been growing rapidly. Studies show that it is necessary to consider the optimized phase change temperature of PCMs within the comfort temperature and specific climate conditions. Thus, the objective of this study is to investigate the best optimized PCM under thermal comfort range in the climate conditions of South Korea, and analyze the energy savings of PCMs, using DesignBuilder. The prepared PCMs were <I>n</I>-octadecane (OT), <I>n</I>-heptadecane (HT), and <I>n</I>-hexadecane (HX), which phase change temperatures were close to the thermal comfort range. The results of the circulation water bath test showed that the phase change temperature of the mixed PCMs by OT and HT was (22–23) °C, within the thermal comfort range. According to the various mixing ratios of OT to HT, the phase change temperatures of PCMs for OH91, OH73, OH55, OH37, and OH19 appeared at ((24–26), (23–24), (22–23), (21–23), and (20–22)) °C, respectively. For energy simulation, gypsum boards with OT, OHs, and HT were prepared, and analyzed by replacing conventional gypsum board of the standard residential construction house model in South Korea. As a result, the maximum energy savings were shown by OH73 in cooling, and OH19 in heating. Consequently, the maximum total energy savings were achieved for OH73, which means that the best optimized PCM for South Korea demonstrated a phase change temperature of (23–24) °C.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Optimization of PCM within comfort temperature in South Korean climate was investigated. </LI> <LI> PCM melting temperature of 24 °C were optimized in cooling. </LI> <LI> PCM melting temperature of 21 °C were optimized in heating. </LI> <LI> There are many variables to improve the efficiency of PCM for energy saving. </LI> </UL> </P>

고령의 호흡기 질환 환자에서 상부 위장관 내시경 검사시 폐기능 장애 정도에 따른 산소 포화도의 변화

정윤형(Yun Hung Jung),이진석(Jin Suk Lee),한종학(Jong Hak Han),김재홍(Jae Hong Kim),정동성(Dong Sung Jung),이귀래(Gwi Lae Lee),한창완(Chang Wan Han),박운식(Woon Sik Park),조영삼(Young Sam Cho),주홍돈(Hong Don Joo),두창준(Chang Joon D 대한내과학회 1995 대한내과학회지 Vol.49 No.2

N/A Objectives : We performed following experiment in order to find the relationship between impairment of pulmonary function test (PFT) and oxygen desaturation during upper gastrointestinal endoscopy examination among the elderly patients. Methods : Pulmonary function test and ABGA (arterial blood gas analysis) were performed before endoscopy. Arterial oxygen saturation and pulse rate were monitored with pulse oximeter before endoscopy until 5minutes its completion. We classified the population by control group and patients group by pulmonary function test. we classified patients group by mild group, moderate group and severe group (Table 2). Results : 1) Oxygen saturation was decreased significantly among all of groups, the most decreased within 1 minutes after insertion endoscopy and recovered soon before endoscopic completion. 2) The duration of worst SaO2 did not correlated with the pulmonary function test impairment. 3) The time of endoscopy did not correlated with decrease in SaO2 during endoscopy 4) There is decreased oxygen saturation in mild group, but no significant change from control group. 6) Pulse rate did not correlated with pulonary function test impairment. Conclualon : Oxygen saturation was decreased all groups in elderly populaton during upper gastro-intestinal endoscopy especially moderate or severe groups, therefore, incidence of cardio-pulmonary disease is increased. To prevent cardio-pulmonary complication, we should detect oxygen desaturation early by using pulse oximeter during upper gastrointestinal endoscopic procedure in moderate or severe group. If needed, termination of the procedure, oxygen supplement or assisted ventilation minimize cardiopulmonary complication.

단안 주시하 체위 변화에 따른 안구회선

전재연,허달웅,장혜란,Jae Yeon Jun M,D,Dalwoong Huh,M,D,Hae Ran Chang,M,D 대한안과학회 2005 대한안과학회지 Vol.46 No.1

Purpose: To determine whether cyclotorsion occurs when a patient moves from the seating to supine position fixating with one eye. Methods: The axis of astigmatism was measured with the handheld automated refractometer (Retinomax K-plus, Nikon, Japan) in 33 eyes having more than -1.0D cylinder in seated and supine positions under monocular fixation. Results: There was a cyclotorsional deviation in 30 eyes (90.90%). Excyclotorsion was shown in 22 eyes (66.67%) and incyclotorsion in 8 (24.24%). Seventeen eyes (51.50%) had a torsional deviation less than 4 degrees, 5 eyes (15.15%) from 5 to 6 degrees, 7 eyes (21.21%) from 7 to 14 degrees and one eye greater than 15 degrees. Conclusions: Positionally induced cyclotorsion occurs under fixation with one eye simulating refractive surgery. Surgeons should therefore make an effort to align the wavefront measurement to the ablation onto the cornea.

메탄올에 의한 중독성 약시의 치험 1예

방재순,양홍석,노승수,장윤희.Jae Soon Bang. M.D.. Hong Seok Yang. M.D.. Seung Soo Rho. M.D.. Yoon-Hee Chang. M.D. 대한안과학회 2007 대한안과학회지 Vol.48 No.12

Purpose: To report a case of visual improvement in methanol poisoning treated with intravenous methylprednisolone. Case summary: A 64-year-old man presented with decreasing vision in both eyes after ingesting a car window cleanser. His initial visual acuity was the ability to count fingers in the right eye and hand motion in the left eye. The patient received intravenous methylprednisolone (1.0 gram), slowly over 1 hour. The same dose of methyl prednisolone was repeated on the second and third day. Then, oral prednisolone was given and tapered over a period of 7 weeks. On the 5th day after treatment, there was an improvement in the visual acuity of the right eye to 0.4 but no improvement of vision was observed in the left eye. On 16th day after treatment, the visual acuity was 0.7 in the right eye and counting fingers in the left eye. At 2 months after ingestion, the visual acuity of the right eye returned to 1.0 with no improvement in the left eye. Optic disc pallor was suspected and P100 delay was observed in the left eye with VEP showing a favorable outcome in the right eye. Conclusions: A visual improvement of 1 eye was observed in methanol poisoning treated with intravenous methylprednisolone.

당뇨황반부종에서 안구내 트리암시놀론 단독주입과 베바시주맙 병합주입의 단기 효과 비교

장민욱,김성우,오인경,오재령,허걸.Min Wook Chang. M.D.. Seoung Woo Kim. M.D.. In Kyung Oh. M.D.. Jae Ryung Oh. M.D.. Kuhl Huh. M.D.. Ph.D. 대한안과학회 2008 대한안과학회지 Vol.49 No.8

Purpose: To compare the effect of intravitreal triamcinolone injection with and without bevacizumab for diabetic macular edema. Methods: Of 69 patients (69 eyes) diagnosed with diabetic macular edema without any history of other intraocular disease or intraocular operation, 45 eyes (45 patients) were injected with intravitreal triamcinolone (4 mg) and the remaining eyes (24 patients) were injected with triamcinolone (2 mg) and bevacizumab (1.25 mg). The visual acuity and central macular thickness of treated eyes from both groups was measured using OCT, and these measurements were compared between the two groups. Results: There were no statistical differences between the two groups with respect to baseline data. Central macular thickness (CMT) was reduced in both groups, and BCVA improved in both groups. No significant differences were detected in changes in CMT or BCVA between the two groups. Conclusions: Intravitreal injection of triamcinolone had a beneficial effect on DME in terms of CMT reduction and BCVA improvement. Addition of three consecutive intravitreal bevacizumab injections, however, did not show any significant addictive effect during the follow-up period. J Korean Ophthalmol Soc 49(8):1269-1274, 2008

갑상선 절제 수술 후 Guardix-SG<SUP>Ⱂ</SUP>의 유착방지 효과

박재현,정종주,강상욱,남기현,장항석,정웅윤,박정수,Jae Hyun Park,M.D.,Jong Ju Jeong,M.D.,Sang Wook Kang,M.D.,Kee Hyun Nam,M.D.,Hang Seok Chang,M.D.,Woong Youn Chung,M.D. and Cheong Soo Park,M.D. 대한갑상선-내분비외과학회 2009 The Koreran journal of Endocrine Surgery Vol.9 No.3

Purpose: Postoperative adhesion of the surgical field seems to be troublesome not only to the patients, but also to the surgeons. Guardix-SG<SUP>Ⱂ</SUP> is a poloxamer/alginate mixture that reduced the incidence of postoperative adhesions when it is added to the abdominal surgery in animal models and also in clinical trials. This study was a randomized, prospective, double-blinded study to evaluate the antiadhesive efficacy and safety of Guardix-SG<SUP>Ⱂ</SUP> after total thyroidectomy. Methods: A total of 89 patients who underwent total thyroidectomy between July 2008 and February 2009 in Severance Hospital and Gang-Nam Severance Hospital were randomized to either the Guardix-SG<SUP>Ⱂ</SUP> treatment group (n=45) or the non-treatmentcontrol group (n=44). The patients were asked about their clinical symptoms (hypesthesia or paresthesia on the operative site (SN) and swallowing discomfort (SW)) by using a questionnaire, and the swallowing function was evaluated using Marshmallow Esophagography by one physician. The clinical symptoms and Marshmallow Esophagography were scored according to the results of assessment. The most severe state was scored as 0 and normal was scored as 3. Results: The scores of the clinical symptoms (SN and SW) were 2.67 and 2.49 in the treatment group, and 2.09 and 1.80 in the control group, respectively, at the postoperative 6th week (P=0.001, <0.001). The scores of the Marshmallow Esophagography were 2.93 in the treatment group and 2.73 in the control group (P=0.033). Abnormal findings were seen in 2 patients (4.4%) in the treatment group and in 10 patients (22.7%) in the control group (P=0.014). Conclusion: Guardix-SG<SUP>Ⱂ</SUP> seems to be effective in preventing adhesion after thyroidectomy. Further studies involving a larger number of subjects will be needed to make an application guideline. (Korean J Endocrine Surg 2009;9: 127-132)

안과적 이상을 동반한 가부키 증후군 1예

임헌섭,안재홍,노승수,유호민,장윤희.Hun-Sub Lim. M.D.. Jae Hong Ahn. M.D.. Seung Soo Rho. M.D.. Ho Min Lew. M.D.. Yoon-Hee Chang. M.D. 대한안과학회 2007 대한안과학회지 Vol.48 No.12

Purpose: Kabuki syndrome is a rare syndrome of multiple congenital anomalies and mental retardation, which is characterized by a peculiar face resembles Kabuki actor, postnatal growth retardation, and skeletal abnormalities. The ocular feature such as strabismus, amblyopia, ptosis, blue sclera and long palpebral fissure with eversion of the lateral portion of lower eyelid can be seen in this syndrome. We experienced a Kabuki syndrome patient with ocular feature. Case Summary: A 6 years old girl visited ophthalmology department for frequent blinking, abnormal movement of eyelid. She showed growth retardation, high palate arch, bifid uvula and low hairline. Best corrected visual acuity was 0.5 in the right eye and 0.4 in the left eye. She also presented with mixed astigmatism (right: +sph 1.00;-cyl 3.00 Ax 180, left: +sph 1.00;-cyl 3.50 Ax 180). In addition, Marcus-Gunn jaw winking in her left eye and a long palpebral fissure were noted. She had intermittent exotropia and a tilted optic disc in the left eye.

OP-21 : Development of an Enzyme - Linked Immunosorbent Assay for the Residues of the Insecticide Imidacloprid

(Jae Koo Lee),(Bruce D . Hammock),(Oee Sook Park),(Ki Chang Ahn),(Ju Hyoung Park) 한국응용생명화학회(구 한국농화학회) 1999 한국응용생명화학회 학술발표회 Vol.1999 No.1

Fin-Width Effects on Characteristics of InGaAs-Based Independent Double-Gate FinFETs

Chang, Sung-Jae,Zhou, Hong,Gong, Nanbo,Kang, Dong-Min,Lim, Jong-Won,Si, Mengwei,Ye, Peide D.,Ma, T. P. IEEE 2017 IEEE electron device letters Vol.38 No.4

<P>We report the characteristics of InGaAs-based independent double-gate FinFETs with Al2O3/LaAlO3 as gate dielectric. The device can be operated in three different modes ( i. e., single-, double-, and independent double-gate) made possible by the physically separated two sidewall gates. When the device is operated in the double-gatemode, it exhibits better performance in terms of the On/Off current ratio, subthreshold swing, Off current, and channel mobility than in the single-gate mode. In addition, independent double-gate operation makes it possible to modulate channel properties by applying a bias at the opposite gate via gate coupling effects. Our systematicmeasurements reveal that gate control and coupling effects are enhanced with reduced fin width.</P>

Development of an ELISA for the Detection of the Residues of the Insecticide Imidacloprid in Agricultural and Environmental Samples

Lee, Jae Koo,Ahn, Ki Chang,Park, Oee Suk,Kang, Shin Young,Bruce D.Hammock 충북대학교 한국과학재단 지정 첨단원예기술개발 연구센터 2002 연구보고서 Vol.6 No.-

A competitive enzyme-linked immunosorbent assay (ELISA) for the chloronicotinyl insecticide imidacloprid was developed using a polyclonal antibody produced against a hapten conjugated through the imidazolidine to keyhole limpet hemocyanin. In the standard curve of imidacloprid, an IC_50 of 17.3 ng/mL was obtained using a competitive heterologous system at pH 10. Very low cross-reactivity was found for some structurally related compounds including the insecticide thiacloprid. The high cross-reactivity with a metabolite containing the carbonyl group in the imidazolidine moiety suggests the involvement of its polarity and stereochemical fitness in forming the antibody-antigen complex. The effects of various assay conditions, including organic solvents, detergent content, salt concentration, and pH on the sensitivity were evaluated. High-performance liquid chromatography was run for comparison to validate the ELISA with fortified water samples, the correlation being 0.997-0.998(n=15) with a slope of 1.10-1.38. The ELISA turned out to be a convenient tool for monitoring imidacloprid residues in agricultural and environmental samples.