• 한국미생물·생명공학회지
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• 제46권4호
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• pp.377-389
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• 2018

In this study, a novel microalgal strain, Desmodesmus sp. KAERI-NJ5, was isolated, identified, and evaluated as a candidate for biodiesel feedstock. In a preliminary study, the effects of four general microalgal growth factors, including temperature, pH, light intensity, and concentration of nitrogen source ($KNO_3$), on the microalgal photoautotrophic growth were evaluated. With the exception of light intensity, the growth factors needed to be optimized for the microalgal biomass production. Optimization was done using response surface methodology. The optimal conditions for biomass production were pH 6.54, $27.66^{\circ}C$, and 0.52 g/l $KNO_3$. The biomass production at the optimal conditions was 1.55 g/l, which correlated well with the predicted value of 1.5 g/l. The total lipid and fatty acid methyl ester contents of the cells grown at the optimal conditions were 49% and 21.2% of cell dry weight, respectively. To increase the lipid content of the biomass, microalgae were challenged by nitrogen starvation. Enhancement of total lipid and fatty acid content up to 52.02% and 49%, respectively, were observed. Lipid analysis of the nitrogen-starved cells revealed that C16 and C18 species accounted for 95.9% of the total fatty acids. Among them, palmitic acid (46.17%) and oleic acid (39.43%) dominantly constituted the algal fatty acids. These results suggest Desmodesmus sp. KAERI-NJ5 as a promising feedstock for biodiesel production.

• 공학교육연구
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• 제21권3호
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• pp.56-65
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• 2018

With rapid advance of technologies including information and communication technologies, jobs are evolving faster than ever. Architectural engineering is no exception in this regard, and the green architectural engineering is emerging fast as a promising new field. In this study, a Delphi study of expert architectural engineers are conducted to find out (1) near future prospects of the field, (2) near future emerging jobs, (3) competencies needed for these jobs, and (4) educational content necessary to build these competencies with regards to the green architectural engineering. Initial Delphi survey consisting of open-ended questions in the above four areas were conducted and came out with 65 items after duplicate removal and semantic refinements. Further refinements via second and third wave of Delphi results into 40 items that the 13 architectural engineering experts may largely agree upon as future prospects with regards to the green architectural engineering. Findings indicate that it is expected that the demand for green architectural engineering and needs for automatic energy control system increase. Also, collaborations with other fields is becoming more and more important in green architectural engineering. The professional work management skills such as knowledge convergence, problem solving, collaboration skills, and creativity linking components from various related areas seem to also be on the increasing need. Near future ready critical skills are found to be the building environment control techniques (thermal, light, sound, and air), the data processing techniques like data mining, energy monitoring, and the control and utilization of environmental analysis software. Experts also agree on new curriculum for green building architecture to be developed with more of converging subjects across disciplines for future ready professional skills and experiences. Major topics to be covered in the near future includes building environment studies, building energy management, energy reduction systems, indoor air quality, global environment and natural phenomena, and machinery and electrical facility. Architectural engineering community should be concerned with building up the competencies identified in this Delphi preparing for fast advancing future.

• Mycobiology
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• 제47권2호
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• pp.230-241
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• 2019

The Great Sebkha of Oran is a closed depression located in northwestern of Algeria. Despite the ranking of this sebkha among the wetlands of global importance by Ramsar Convention in 2002, no studies on the fungal community in this area have been carried out. In our study, samples were collected from two different regions. The first region is characterized by halophilic vegetation and cereal crops and the second by a total absence of vegetation. The isolated strains were identified morphologically then by molecular analysis. The biotechnological interest of the strains was evaluated by testing their ability to grow at different concentration of NaCl and to produce extracellular enzymes (i.e., lipase, amylase, protease, and cellulase) on solid medium. The results showed that the soil of sebkha is alkaline, with the exception of the soil of cereal crops that is neutral, and extremely saline. In this work, the species Gymnoascus halophilus, Trichoderma gamsii, the two phytopathogenic fungi, Fusarium brachygibbosum and Penicillium allii, and the teleomorphic form of P. longicatenatum observed for the first time in this species, were isolated for the first time in Algeria. The halotolerance test revealed that the majority of the isolated are halotolerant. Wallemia sp. and two strains of G. halophilus are the only obligate halophilic strains. All strains are capable to secrete at least one of the four tested enzymes. The most interesting species presenting the highest enzymatic index were Aspergillus sp. strain A4, Chaetomium sp. strain H1, P. vinaceum, G. halophilus, Wallemia sp. and Ustilago cynodontis.

• The Journal of Advanced Prosthodontics
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• 제11권4호
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• pp.215-222
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• 2019

PURPOSE. To evaluate the polishing effect on roughness and color change of pressed and layering ceramics after immersion in coffee solution. MATERIALS AND METHODS. 88 ceramic discs ($1.0mm{\times}10.0mm$) were manufactured - 44 nano-fluorapatite layering ceramics (IPS e.max Ceram. Group C) and 44 pressed lithium disilicate ceramic discs (IPS e. max Press - Group P). Each group was divided into 4 subgroups according to surface treatments: (G) Glaze, (S) Shofu polishing system (Shofu Inc.), (E) Edenta AG polishing System, (KG) $30-{\mu}m$ diamond granulation tip. Surface roughness (Ra) and color change (${\Delta}E$) measurings after the surface treatments were performed, before and 12 days after the immersion in coffee solution. A samples' qualitative analysis was conducted with a scanning electron microscopy (SEM). Data were statistically-treated with one-way-ANOVA and Duncan's tests, apart from paired t-test and Pearson's correlation test (${\alpha}=5%$). RESULTS. The decrescent order, both for surface roughness (Ra) and ${\Delta}E$ for both ceramics were: KG > E > S > G (P<.05). With exception for PG and CG subgroups, which did not present statistical difference between them, all other pressed ceramics subgroups presented smaller Ra values and greater ${\Delta}E$ values than the layering ceramics subgroups (P<.05). CONCLUSION. Although mechanical polishing systems presented intermediate Ra values, their colors were considered clinically acceptable. There is a strong correlation between the surface roughness and the color change of tested ceramics.

• 대한한방내과학회지
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• 제40권4호
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• pp.675-696
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• 2019

Objective: This study was aimed at evaluating the effect and clarifying the treatment period of Korean medicine treatment for cerebral infarction. Method: This study was carried out on patients with hemiplegia who were hospitalized in the Department of Korean Internal Medicine of Jecheon Korean Medicine Hospital of Semyung University from June 2014 to May 2019. A retrospective study was performed on 253 patients who were diagnosed with cerebral infarction by brain CT or nuclear magnetic resonance imaging. Results and Conclusion: 1. Korean medicine treatment has a significant effect on improving the movement disorder and daily life independence of cerebral infarction. 2. In the group that started Korean medical treatment within one month after the onset of cerebral infarction, with the exception of MMSE-K, the indicators related to the movement disorder and daily life independence showed significant effect. 3. MMSE-K showed no statistically significant change in any of the patient groups. 4. Within three months after the onset date, the longer the period of treatment with Korean medicine, the better the symptom improvement of upper extremity movement disorder. 5. The longer the hospital stays, the better the symptom improvement of the lower extremity movement disorder. 6. The combination of Korean and Western medicine did not affect liver or kidney function.

• Archives of Plastic Surgery
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• 제46권2호
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• pp.108-113
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• 2019

Background The aim of this study was to assess the safety of one-per-mil tumescent injections into viable skin flaps that had survived an ischemic insult, in order to assess the potential suitability of one-per-mil tumescent injections in future secondary reconstructive procedures such as flap revision and refinements after replantation. Methods Forty groin flaps harvested from 20 healthy Wistar rats weighing 220 to 270 g were subjected to acute ischemia by clamping the pedicle for 15 minutes. All flaps showing total survival on the 7th postoperative day were randomly divided into group A (one-per-mil tumescent infiltration; n=14), group B (normal saline infiltration; n=13), and group C (control, with no infiltration; n=13) before being re-elevated. Transcutaneous oxygen tension ($TcPO_2$) was measured before and after infiltration, and changes in $TcPO_2$ were statistically analyzed using analysis of variance, the paired t-test, and the independent t-test. The viability of flaps was also assessed using the Analyzing Digital Images software at 7 days after the second elevation. Results Thirty-nine flaps survived to the final assessment, with the sole exception of a flap from group A that did not survive the first elevation. $TcPO_2$ readings showed significant decreases (P<0.05) following both one-per-mil tumescent ($99.9{\pm}5.7mmHg$ vs. $37.2{\pm}6.3mmHg$) and normal saline ($103{\pm}8.5mmHg$ vs. $48.7{\pm}5.9mmHg$) infiltration. Moreover, all groin flaps survived with no signs of tissue necrosis. Conclusions One-per-mil tumescent infiltration into groin flap tissue that had survived ischemia did not result in tissue necrosis, although the flaps experienced a significant decrease of cutaneous oxygenation.

• 예술인문사회 융합 멀티미디어 논문지
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• 제9권10호
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• pp.923-934
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• 2019

본 연구는 도시 및 건축형태요소와 미기후가 건축물군의 에너지 사용량에 미치는 영향을 도출하는 것을 목적으로 한다. 본 연구에서는 건축물 에너지 사용량에 영향을 미치는 미시적 요소로 도시형태 및 도시조직, 건축물 형태 및 특성, 미기후 등의 요소를 중심으로 접근했다. 이러한 분석을 위해서 2017년 건축물 에너지 사용량 자료 중 서울시 내 건축물들의 8월 에너지 사용량 자료를 중심으로 분석을 수행하였다. 기상청에서 서울시 내에 설치한 23개의 AWS의 반경 500m의 미시적 요소들을 조사하여 데이터를 구축하였다. 본 연구에서는 건축물 에너지 사용량과 건축물 형태요소 외에 도시형태요소, 미기후요소 간의 관계를 분석하기 위해서 위계적 회귀분석을 이용하여 비교·분석하였다. 분석결과, 도시형태 및 도시조직 변수들은 모두는 아니었지만 대체로 건축물 에너지 사용량과 유의미한 관계를 맺고 있었다. 온도 외에 풍속, 습도 등의 미기후 변수들은 모두 건축물 에너지 사용량을 설명하는데 필요한 변수임을 도출했다.

• 한국산업보건학회지
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• 제31권3호
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• pp.255-265
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• 2021

Objectives: The purpose of this study is to analyze the exposure characteristics of inorganic acids. Methods: We analyzed exposure data (n = 363,146) for six inorganic acids (hydrogen fluoride, hydrogen bromide, hydrogen chloride, phosphoric acid, nitric acid, and sulfuric acid) collected between 2017 and 2019 in South Korea. Measurement characteristics and exposure levels (ELs) were analyzed by inorganic acid, industry category, enterprise size, and measurement year. Results: Measurement percentage dominated in time-weighted average (TWA, 91%) compared to short term exposure limit (STEL) and Ceiling. Most of the measurements (79.7%) were collected from the manufacturing category of industry. Medians of ELs were mostly low (≤3% of the threshold limit), with the exception of sulfuric acid (4.6% of TWA and 10.5% of STEL). The percentages of exceeding 1% of the occupational exposure limits (OELs) in TWA were relatively high for sulfuric acid (35.8%) and hydrogen chloride (16.5%) compared to the other acids (4.2%-6.6%). In addition, the percentages of exceeding 1% of OELs in STEL or Ceiling were higher for sulfuric acid (22.9%), hydrogen chloride (12.3%), and nitric acid (8.2%) compared to the other acids (1.2%-1.9%). The small-sized enterprises showed higher ELs in TWA; contrarily, the large-sized enterprises had higher ELs in STEL or Ceiling. Conclusions: The measurement characteristics and ELs identified in this study could be useful for establishing safety and health policies for inorganic acids.

• 동의신경정신과학회지
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• 제31권4호
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• pp.279-288
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• 2020

Objectives: Many fields have changed since covid-19, psychotherapy being no exception. With the pandemic associated increase in untact treatment, interest in virtual reality exposure therapy has also increased. The aim of study was to analyze recent literature using virtual reality therapy for the treatment of anxiety disorders. Methods: We searched five databases from dates between October 1 to November 1, 2020. We selected articles related to the treatment of anxiety disorders using virtual reality therapy and analyzed the trend of that, not thesis but domestic articles. Results: There were 6 RCT studies and 3 were case reports where, based on the DSM-4, the participants presented with anxiety disorders including 2 with presentation anxiety, 1 heterosexual anxiety, 1 test anxiety, 1 social anxiety, 1 dental anxiety, 2 Acrophobia, and 1 social phobia. Treatment sessions varied from 1 session to 18 sessions, but 5 studies conducted 4 sessions, and all studies attempted virtual reality exposure for 30-minute time periods. 8 studies used HMD as the VR device and 1 study did not report a device. Conclusions: Anxiety disorders treated using virtual reality included speech anxiety and acrophobia. Median treatment session number was 4 and sessions were less than 30 minutes. The most common VR device used was an HMD. VR psychotherapy showed limitations relating to patient experience including cyber sickness and a lack of immersion. In addition, most of the studies were conducted with patients who visited hospitals utilizing Western medical practices. Currently, virtual reality therapy (VRT) intervention in oriental medicine is lacking. The lack of research in this area suggests analyzing data from VR psychotherapy in oriental medicine could provide novel and useful information.

• 대한금속재료학회지
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• 제49권7호
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• pp.549-556
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• 2011

This study aimed to evaluate the performance of diffusion barriers in order to prevent fuel-cladding chemical interaction (FCCI) between the metallic fuels and the cladding materials, a potential hazard for nuclear fuel in sodium-cooled fast reactors. In order to prevent FCCI, Zr or V metal is deposited on the ferritic-martensitic stainless steel surface by physical vapor deposition with a thickness up to $5{\mu}m$. The diffusion couple tests using uranium alloy (U-10Zr) and a rare earth metal such as Ce-La alloy and Nd were performed at temperatures between 660~800$^{\circ}C$. Microstructural analysis using SEM was carried out over the coupled specimen. The results show that significant interdiffusion and an associated eutectic reaction ocurred in the specimen without a diffusion barrier. However, with the exception of the local dissolution of the Zr layer in the Ce-La alloy, the specimens deposited with Zr and V exhibited superior eutectic resistance to the uranium alloy and rare earth metal.