• 한국환경농학회지
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• 제31권2호
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• pp.185-191
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• 2012

본 연구에서는 산업폐수로부터 분리한 3가지 종의 인 제거율을 확인하였다. 3 가지 분리된 균을 동정한 결과 A1균은 Stenotrophomonas maltophilia strain CUPS 3, A2균은 Rhodococcus erythropolis strain Sco-C01, A3균은 Bacillus sp. 3434BRRJ이었다. 3 가지 분리된 균의 인 제거 및 경유분해를 확인한 결과 인 제거율은 Bacillus sp. 3434BRRJ > Stenotrophomonas maltophilia strain CUPS균 > Rhodococcus erythropolis strain Sco-C01균 순으로 높은 것으로 나타났으며 제거율은 약 99%, 50%, 20%로 확인되었다. 따라서 이 후 실험은 인 제거율이 가장 높았던 Bacillus sp. 3434BRRJ를 가지고 실험하였다. Bacillus sp. 3434BRRJ의 인 제거를 확인하기 위하여 온도별(15, 25 그리고 $30^{\circ}C$), 인 농도별(20, 30 그리고 40 mg/L) 그리고 산소조건(호기, 혐기/호기조건) 및 탄소원을 달리하여 실험하였다. 그 결과Bacillus sp. 3434BRRJ는 $30^{\circ}C$에서 인 제거가 가장 좋았으며 20 mg/L의 인은 약 99% 처리하였고 혐기조건을 거치고 탄소원으로 acetate와 glucose를 혼합하여 처리하였을 때 가장 효율이 좋은 것으로 나타났다. 본 연구에서는 Bacillus sp. 3434BRRJ의 인 제거를 확인 하였다. 균의 생장이 높을수록 인의 제거율은 높았으며, 미생물을 이용한 환경오염물질의 제거에 있어서 가장 중요한 것은 미생물의 활성을 높이는 환경조건을 제공하는 것이다.

• 한국환경농학회지
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• 제30권3호
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• pp.310-315
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• 2011

폐미역을 이용한 생물흡착제의 중금속 제거능력을 조사하기 위해 lab-scale의 생물흡착시스템에서 최적조건을 구명하고, lab-scale의 생물흡착시스템의 최적조건하에서 large-scale PBCC 시스템의 중금속 제거능력을 조사하였다. Lab-scale 생물흡착시스템별 중금속 제거능력은 PBCC보다 CSTR이 뛰어났지만 CSTR은 폐수유입속도가 48 L/day이상에서 완전혼합상태를 유지하지 못하여 안정적인 운전이 가능한 PBCC가 적합하였다. Cu용액의 유입속도 및 농도별 Cu 제거능력은 유입속도 12 L/day 및 유입농도 10 mg/L일 때 Cu용액 처리량이 가장 뛰어났으나 경제적인 부분을 검토한 결과 유입속도 24 L/day 및 유입농도 100 mg/L가 적절할 것으로 판단되었다. 처리단계별 Cu 제거능력은 컬럼을 연속식으로 배열하는 것이 Cu 제거효율이 높았다. 중금속 종류별 제거능력은 Pb, Cr의 처리효율이 높았고 Cu용액 이외의 다른 중금속 용액들도 Cu와 동등한 수준 이상의 처리효율을 나타내었다. Lab-scale의 PBCC 시스템을 27배 규모로 scale-up한 large-scale PBCC 시스템의 Cu 제거능력은 138 L로 lab-scale의 5 L와 비교하였을 때 동등한 수준을 유지하였다. 따라서 중금속 처리를 위한 최적 폐미역 활용 생물흡착시스템은 PBCC 시스템인 것으로 판단되나, 실제 중금속 폐수에 본 최적시스템을 적용하기 위해서는 중금속 폐수 특성에 따른 적용성 연구가 추가로 진행되어야 할 것으로 판단된다.

• Journal of Yeungnam Medical Science
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• 제18권1호
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• pp.75-84
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• 2001

1997년 1월부터 2001년 4월까지 영남대학교 의과대학 부속병원 소아과에 이물질을 삼켜 내원한 15세 이하의 환아를 대상으로 성별 및 연령에 따른 발생빈도, 발생시간, 이물질의 크기와 종류 및 위장관내의 위치, 임상증상, 이물질에 의한 위내시경 소견, 이물질의 제거 혹은 자연 배출되기까지의 기간, 치료 방법 등을 조사 분석하였다. 성별 분포는 총 37례 중 남아가 25예(67.5%) 여아가 12예(32.5%)였으며, 남녀비는 2.1:1이였다. 연령별 분포는 1세 이상 2세 미만이 7예(19%)로 가장 많았다. 이물질을 삼킨 시간별 분포는 오후 3시와 4시경이 11예로 가장 많았으며 대부분이 오후에 발생하였다. 이물질의 종류로는 동전이 20예(54%), 손목에 끼는 팔찌자석, 바둑알, 탄력붕대를 고정하는 클립, 열쇠고리, 빨래집게에 부착된 C형의 클립이 각각 1예였다. 위장관내 이물질의 위치는 위장이 16예(43.2%)로 가장 많았으며 상부식도가 12예(32.5%), 소장이 5예(13.5%), 하부식도가 4예(10.8%)였다. 병원에 도착 당시의 임상증상은 무증상이 22예(59.4%)로 가장 많았으며, 구토가 7예(19.0%), 상복부 통증이 3예(8.1%), 오심과 연하곤란이 각각 2예(5.4%), 복통이 1예(2.7%)였다. 치료방법으로 이물질을 삼킨 총 37예 중 20예(54.0%)에서 내시경으로 이물질이 제거되었으며, 3예(8.1%)에서는 이물질의 자연 배출이 확인되었고, 수술적 제거를 시행한 경우는 없었다. 이물질을 삼킨 후 제거될 때까지의 시간은 12예(52.2%)가 12시간 이내에 제거되었으며, 4예(17.4%)가 24시간 이내에 제거되었고, 가장 긴 기간은 7일이었다. 내시경으로 이물질이 제거된 환아에서의 내시경 소견은 15예에서는 정상 소견이었으며, 5예에서 이물질에 의한 이상소견이 있었다. 상부 위장관 이물질을 제거하기 위해 내시경을 시행한 경우 안전하게 이물질을 제거할 수 있었으며 내시경을 시행함에 따른 부작용이나 합병증은 없었다. 따라서 소아에서 상부위장관 이물질의 제거에는 위내시경이 안전한 방법으로 생각되어진다.

• 한국대기환경학회지
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• 제33권2호
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• pp.87-96
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• 2017

In this study, 4 gases containing typical chlorinated volatile organic compounds (VOCs) were treated by ultraviolet (UV) irradiation. The typical chlorinated VOCs are dichloromethane (DCM), trichloromethane (TCM), carbon tetrachloride (CTC) and trichloroethylene (TCE). The removal efficiency (RE) and the products of chlorinated VOCs by UV irradiation are investigated. At this time, 2 types of background gas (air and nitrogen) were used to figure out the RE by photooxidation and photolysis. The specification of UV-lamp used in this study was low-pressure mercury lamp emitting wavelength of 185~254 nm. The experimental conditions were set as initial VOC concentration of $180{\pm}10ppm$, empty bed retention time (EBRT) of 53 s, temperature of $23{\pm}2^{\circ}C$ and relative humidity of $65{\pm}5%$. In the photolysis condition with nitrogen ($N_2$) as background gas, the averaged RE of the 4 types of chlorinated VOCs was about 24% higher than that with photooxidation; and the REs of VOCs except CTC were confirmed as >99%. The composition of off-gases after UV photooxidation in air was investigated and several intermediates from DCM, TCM and TCE were detected by GC/MS. Among them, phosgene which is a toxics was detected as an intermediate of TCM. In addition, the concentration of carbon dioxide ($CO_2$) in the off-gases was measured to calculate the mineralization rate (MR). With the photooxidation, TCE showed the highest RE (>99%) while MR was the lowest (17%); and the MR of DCM was the highest (86%). In addition, particulate matters (PM) in the off-gases was also detected and high concentrated $PM_{10}$ ($21,580{\mu}g{\cdot}m^{-3}$) and $PM_{2.5}$ ($6,346{\mu}g{\cdot}m^{-3}$) were detected in TCE off-gas. More than 99% of the chlorinated VOCs could be removed using UV254-185 nm lamp, while it is necessary to conduct further studies on the production and treatment of secondary pollutants.

• Journal of Chest Surgery
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• 제43권6호
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• pp.669-674
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• 2010

배경: 자연성 혈기흉은 외상이나 다른 뚜렷한 원인 없이 흉강 내 공기와 400 mL 이상의 혈액이 동시에 쌓이는 질환이다. 드문 질환이지만 생명을 위협할 수도 있는 질환이기도 하다. 이 질환의 적절한 치료를 알아보고자 두 병원에서 치료받은 환자들을 분석하였다. 대상 및 방법: 2003년 3월부터 2010년 8월까지 치료받은 18명의 자연성 혈기흉 환자들을 후향적으로 조사하였다. 결과: 18명의 환자들 중 남자 15명 여자 3명이었고 평균 나이는 24.6세이었다. 16명의 환자는 우선적으로 폐쇄식 흉관 삽입술을 시행하였으며 15명의 환자는 흉강경을 통한 수술적 치료를 하였다. 수술 후 흉관 제거는 평균 2.9일에 이루어졌으며, 수술 후 합병증으로 흉관 제거 후 기흉이 한 명 있었다. 퇴원 후 다른 합병증이나 재발은 추적기간 동안 없었다. 결론: 초기의 적절한 진단과 치료가 치명적인 쇼크 상태를 방지하며, 흉강경을 통한 조기 수술이 자연성 혈기흉의 치료가 될 것이다. 그러나 보전적 치료도 일부 환자에게는 효과적이다.

• 천문학논총
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• 제32권1호
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• pp.59-61
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• 2017

The AKARI 9 and 18 µm diffuse maps reveal the all-sky distribution of the interstellar medium with relatively high spatial resolution of ~6". The zodiacal light is a dominant foreground component in the mid-infrared. Thus, removal of the zodiacal light is a critical issue to study low surface brightness Galactic diffuse emission. We carried out modeling of the zodiacal light based on the Kelsall model which is constructed from the COBE data. In the previous study, only a time-varying component of the zodiacal light brightness was used for determination of the model parameters. However, there remains a residual component of the zodiacal light around the ecliptic plane even after removal with the model. Therefore, instead of using a time-varying component, we use the absolute brightness of the zodiacal light and we find that the new model can better remove the residual component. As a result, the best-fit model parameters are changed from those in the previous study. We discuss the properties of the zodiacal light based on our new result.

• Journal of Dental Anesthesia and Pain Medicine
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• 제19권6호
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• pp.379-388
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• 2019

Background: In dentistry, pain is a factor that negatively affects treatments and drug use. The aim of this study was to evaluate the correlations of the postoperative analgesic use with pain catastrophizing and anxiety in patients who underwent removal of an impacted mandibular third molar. Methods: We recruited 92 patients who underwent the extraction of impacted mandibular third molar. In this study, the Pederson index was used to preoperatively determine the difficulty of surgical extraction. Patients were asked to note the number of analgesics used for 7 postoperative days. Patients were divided into two groups based on the Pain Catastrophizing Scale: low and high score groups. State-Trait Anxiety Inventory-trait and State-Trait Anxiety Inventory-state questionnaires were used to determine the anxiety levels of the patients. The obtained data were examined to evaluate the correlations of pain catastrophizing and anxiety with the postoperative analgesic use. Results: In this study, 92 patients, including 60 women and 32 men, were recruited. The analgesic use was higher in women than in men but with no significant difference (P > 0.05). Pain Catastrophizing Scale scores were higher in women than in men but with no significant difference (P > 0.05). The analgesic use was higher in patients with high pain catastrophizing than in those with low pain catastrophizing but with no significant difference (P > 0.05). State-Trait Anxiety Inventory-trait scores were higher in women than in men but with no significant difference. However, state-Trait Anxiety Inventory-state scores were significantly higher in women than in men (P < 0.05). Conclusion: The postoperative analgesic use may be higher in patients who catastrophize pain than in others. Knowing the patient's catastrophic characteristics preoperatively would contribute to successful pain management and appropriate drug selection.

• 대한후두음성언어의학회지
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• 제27권1호
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• pp.40-44
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• 2016

Background and Objectives : Surgery is considered the primary treatment for intracordal cyst. However, patients who had undergone surgery are still subject to recurrence and continued voice changes. Intracordal cysts naturally disappear in some patient population. Cyst does not always recur in patients who had received partial surgical removal, too. Contradicting results raises a question whether complete surgical removal of intracordal cyst is necessary and demonstrate need for better treatment. Herein, the author proposes novel surgical method technique intralaryngeal needle technique (INT), a technique using surgical needle for not only injection but also for aspiration and excision of cyst. This study aims to examine the potential of intralaryngeal needle technique in treating intracordal cysts. Materials and Methods : Surgical procedures were done on in-patients diagnosed with intracordal cyst. 23 patients received follow-up screening after the surgery for one year. Patients' subjective satisfaction levels, acoustic measures, aerodynamic measures, laryngeal stroboscopic results were compared before and after the treatment. Results : Overall patients were satisfied with novel surgical excision method. In terms of aerodynamic measures, maximum phonation time, mean air flow rate improved after the surgery. In terms of acoustic measures, Jitter, Shimmer, NHR, and voice pitch changes after the treatment showed statistically significant differences. Laryngeal stroboscopy results showed significant decreases in cyst sizes. Post-surgery patients had improved mucosal waves and amplitudes values. Conclusion : The results show the validity of intralaryngeal needle technique in reducing intracordal cyst size by excision, aspiration, and injection. The author believes this novel technique can be used as an alternative surgical method for intracordal cysts.

• Journal of Welding and Joining
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• 제33권2호
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• pp.14-17
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• 2015

Cleaning effect is well known mechanism of oxide layer removal in DCEP polarity. It is also known that DCEN has higher heat input efficiency than DCEP in GTAW process. Based on these two renowned arc theories, conventional variable polarity arc for aluminum welding was set up to have minimum DCEP and maximum DCEN duty ratio to achieve the highest heat input efficiency and weldability increase. However, recent several variable polarity GTA research papers reported unexpected result of proportional relationship between DCEP duty ratio and heat input. The authors also observed the same result then suggested combination of tunneling effect and random walk of cathode spot to fill up the gap between experiment and conventional arc theory. In this research, suggested combinational work of tunneling effect and rapid cathode spot changing is applied to another unexpected phenomena of variable polarity aluminum arc welding. From previous research, it is reported that wider oxide removal range, narrower bead width and shallower penetration depth are observed in thin oxide layered aluminum compared to the case of thick oxide. This result was reported for the first time and it was hard to explain the reason at that time therefore the inference by the authors was hardly acceptable. However, the suggested combinational theory successfully explains the result of the previous report in logical way.

• The Korean Journal of Pain
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• 제11권1호
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• pp.41-46
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• 1998

Background: Preoperative analgesia may prevent nociceptive inputs generated during surgery from sensitizing central neurons and therefore may preempt postoperative pain. Although preemptive analgesia has shown to decrease postinjury pain in animals, studies in human are not consistent. We studied whether epidural morphine injection before surgical incision could affect postoperative pain and analgesic demands, compared with injection after removal of specimen. Methods: Forty patients scheduled for radical subtotal gastrectomy were randomly assigned to one of two groups for prospective study in a double-blind manner. Group 1 received an epidural injection of 3 mg of morphine in 8 ml of 0.9% saline before surgical incision, and Group 2 after removal of specimen. Postoperative pain relief was provided with I.V. patient controlled analgesia (PCA) system. Numerical rating scales for pain and mood, Prince Henry Hospital scores for pain, cumulative PCA analgesic consumptions, and incidence of side effects were assessed at 2, 6, 12, 24, 48 hours after operation. Results: Cumulative PCA analgesic consumption in group 1 was significantly less than in group 2 at 2, 6 hours after surgery. Pain scores and the incidence of side effects were similar in both groups. Conclusions: Preoperative analgesia with epidural morphine showed little difference in patient controlled analgesic consumption after upper abdominal surgery compaired to intraoperative morphine.