• Title/Summary/Keyword: minimal condition

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Local Flap Algorithm for the Reconstruction of Anterior Chest Wall Defects (전흉부 재건을 위한 국소 피판술의 선택)

  • Kim, Ji Hoon;Kim, Eui Sik;Hwang, Jae Ha;Kim, Kwang Seog;Lee, Sam Yong
    • Archives of Plastic Surgery
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    • v.36 no.4
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    • pp.397-405
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    • 2009
  • Purpose: Soft tissue defect of anterior chest wall is caused by trauma, infection, tumors and irradiation. To reconstruct damaged anterior chest wall does require to consider the patient's body condition, the cause, the location, the depth and the size of deletion, the circulation of surrounding tissue and minimization of functional and cosmetic disability. In this report, we suggest the algorithm of configuration for reconstruction methods. Methods: A retrospective study of 20 patients who underwent anterior chest wall reconstruction with pedicled musculocutaneous flap and fasciocutaneous flap was conducted. We collected the information of the patient's body condition, the cause, the size, the depth and the location of deletion, implemented flap and complication. We observed and evaluated flap compatibility, functional and cosmetic results. Patients completed survey about the extent to their satisfaction. Result: Follow up period after surgery was from 6 to 26 months, survival of flap were confirmed in all of patients' case. Two cases of local necrosis, one case of wound disruption were reported, but all these were cured by the debridement and primary closure. One hematoma and one seroma formation were observed in donor site. Longer surgery time, more bleeding amount and more transfusion volume were reported in the group of musculocutenous flap. Conclusion: Long term follow up result showed the successful reconstruction in all patients without recurrence and with minimal donor site morbidity. In addition, the patients' satisfaction for cosmetic and functional results were scaled relatively higher. This confirmed the importance of reconstruction algorithm for the chest wall reconstruction.

Study on the adsorption of Heavy Metals by Chitin, Chitosan, Cellulose and its Composite Beads (Chintin, Chitosan, Cellulose 및 혼합 Beads의 중금속 이온 흡착특성에 관한 연구)

  • 전수진;유병태
    • Journal of environmental and Sanitary engineering
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    • v.10 no.2
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    • pp.1-12
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    • 1995
  • Under accelerated industrial developments environment pollution comes out to be very stirious. Especially the ions of heavy metal from wastewater, even if they are minimal, accumulated in ecology circle and do finally injury to human health. The general process for removal of heavy metals include coagulation and following sedimentation, ion -exchange and active carbon adsorption and sedimentation that applicate in popular, needs the expense of coagulant the additional treatment of sludge on the general process of coagulation and sedimentation. It is also a serious problem that the second pollution caused by coagulant. However chelating adsorption that uses natural chelating high- molecular compound has not pollution problem Among chelating high- molecules, the diminishing chitin that contained in crustaceans as crawfish and crab in our country with affluent water resources are easy to get. So it is advantageous to use this ubiquitous material for removing heavy metals because we could reuse natural resource. In this research, the author tested the effectiveness of the adsorption and removal of heavy metal ions by chitin and its derivatives. Chitin and cellulose became beads and used as flocculant, in this test. The results are as follows . First, bead showed higher removal ratio than powder in the comparative test on adsorbents such as chitin, chitosan and cellulose. Secondly, in the variety test by the kinds of adsorbent and time. chitosan bead and cellulose bead that showed the highest removal ratio. One hour need to remove the ions of heavy metal. Thirdly, the results of the adsorption degree test by pH revealed high removal ratio adsorption of chitin, cellulose and chitosan bead in alkalin condition but chitosan bead in acidic condition.

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Biodegradation of Pentachlorophenol by Various White Rot Fungi (수질분해균(水質分解菌)에 의한 Pentachlorophenol의 미생물분해(微生物分解))

  • Choi, In-Gyu;Ahn, Sye-Hee
    • Journal of the Korean Wood Science and Technology
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    • v.26 no.3
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    • pp.53-62
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    • 1998
  • In this research, 7 species of white rot fungi were used for determining the resistance against pentachlorophenol (PCP). Three fungi with good PCP resistance were selected for evaluating the biodegradability, and biodegradation mechanism by HPLC and GC/MS spectrometry. Among 7 fungi, there were significant differences on PCP resistance on 4 different PCP concentrations. In the concentrations of 50 and 100ppm ($\mu$g of PCP per g of 2% malt extract agar), most fungi were easily able to grow, and well suited to newly PCP-added condition, but in that of more than 250ppm, the mycelia growths of Ganoderma lucidum 20435, G. lucidum 20432, Pleurotus ostreatus, and Daldinia concentrica were significantly inhibited or even stopped by the addition of PCP to the culture. However, Trametes versicolor, Phanerochaete chrysosporium, and Inonotus cuticularis still kept growing at 250ppm, indicating the potential utilization of wood rot fungi to high concentrated PCP biodegradation. Particularly, P. chrysosporium even showed very rapid growth rate at more than 500ppm of PCP concentration. Three selected fungi based on the above results showed an excellent biodegradability against PCP. P. chrysosporium degraded PCP up to 84% on the first day of incubation, and during 7 days, most of added PCP were degraded. T. versicolor also showed more than 90% of biodegradability at 7th day, and even though the initial stage of degradation was very slow, I. cuticularis has been approached to 90% at 21 st day after incubation with dense growing pattern of mycelia. Therefore, the PCP biodegradability was definitely dependent on the rapid suitability of fungi to newly PCP-added condition. In addition, the PCP biodegradation by filtrates of P. chrysosporium, T. versicolor, and I. cuticularis was very minimal or limited, suggesting that the extracellular enzyme system may be not so significantly related to the PCP biodegradation. Among the biodegradation metabolites of PCP, the most abundant one was pentachloroanisole which resulted in a little weaker toxicity than PCP, and others were tetrachlorophenol, tetrachloro-hydroquinone, benzoic acid, and salicylic acid, suggesting that PCP may be biodegraded by several sequential reactions such as methylation, radical-induced oxidation, dechlorination, and hydroxylation.

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Intraspecific Protoplast Fusion of Cellulolytic Fungus, Penicillium verruculosum (Penicillium verruculosum의 종내 원형질체 융합)

  • Chung, Ki-Chul;Park, Chang-Ryeol;Suk Bai;Chun, Soon-Bai;Kim, Ki-Chung
    • Microbiology and Biotechnology Letters
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    • v.16 no.2
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    • pp.163-167
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    • 1988
  • The conditions for the protoplast fusion of auxotrophic mutants of Penicillium verruculosum were determined. A preparation of commercial enzyme Novozym 234 was used to successfully isolate protoplast from the 20hr old mycelium of P. verruculosum. Under optimal condition, the protoplast yield ranged from 2.4$\times$10$^7$ to 3.0$\times$10$^7$ protoplasts from 400mg of damp mycelia of various auxotrophic mutant strains. The regeneration frequency ranged from 26.6 to 42.4% and the spontaneous reversion frequency of the protoplasts on the regeneration minimal medium was less than 10$^7$. The optimal concentration of PEG 6000 was 20%, and exposure of protoplasts to PEG for 10 min was found to be sufficient for protoplast fusion. Optimal pH of fusion mixture was deter-mined as 5.5 and l0mM of calcium chloride in fusion mixture effectively enhanced the protoplast fusion frequency. Under optimal condition, the fusion frequency between various auxotrophs ranged from 1.8$\times$10$^{-3}$ to 3.5$\times$0$^{-3}$.

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AN EXPERIMENTAL STUDY ON THE READABILITY OF THE DIGITAL IMAGES IN THE FURCAL BONE DEFECTS (디지털영상의 치근이개부 골손실 판독효과에 관한 실험적 연구)

  • Oh Bong-Hyeon;Hwang Eui-Hwan;Lee Sang-Rae
    • Journal of Korean Academy of Oral and Maxillofacial Radiology
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    • v.25 no.2
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    • pp.363-373
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    • 1995
  • The aim of this study was to evaluate and compare observer performance between conventional radiographs and their digitized images for the detection of bone loss in the bifurcation of mandiblar first molar. One dried human mandible with minimal periodontal bone loss around the first molar was selected and serially enlarged 17 step defects were prepared in the bifurcation area. The mandible was radiographed with exposure time of 0.12, 0.20, 0.25, 0.32, 0.40, 0.64 seconds, after each successive step in the preperation and all radiographs were digitized with IBM-PC/32 bit-Dx compatible, video camera (VM-S8200, Hitachi Co., Japan), and color monitor(Multisync 3D, NEC, Japan). Sylvia Image Capture Board for the ADC(analog to digital converter) was used. The obtained results were as follows: 1. In the conventional radiographs, the mean score of the readability was higher at the condition of exposure time with 0.32 second. Also, as the size of artificial lesion was increased, the readability of radiographs was elevated (P<0.05). 2. In the digital images, the mean score of the readability was higher at the condition of exposure time with 0.40 second. Also, as the size of artificial lesion was increased, the readability of digital images was elevated(P<0.05). 3. At the same exposure time, the mean scores of readibility were mostly higher in the digitized images. As the exposure time was increased, the digital images were superior to radiographs in readability. 4. As the size of lesion was changed, the digital images were superior to radiographs in detecting small lesion. 5. The coefficient of variation of mean score has no significant difference between digital images and radiographs.

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A Study for Changes of Blood Pressure and Heart Rate by Acupressure to Acupoints in Rat Model of Hemorrhagic Shock (출혈성 쇼크 흰쥐 모델에서 경혈 지압이 혈압과 심박수 변화에 미치는 영향)

  • Yang, Seung-Bum;Byun, Sin-Kyu;Kim, Jae-Hyo
    • Korean Journal of Acupuncture
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    • v.33 no.2
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    • pp.58-66
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    • 2016
  • Objectives : In order to find a possible non-invasive manipulation tool for maintenance of the cardiovascular functions in hemorrhagic shock, this study was aimed at evaluating effects of acupoints acupressure on the changes in blood pressure and heart rate from an animal model of hemorrhagic shock. Methods : In adult Sprague-Dawley rats, hemorrhagic shock was induced by a withdrawal of arterial blood from the femoral artery with volume of 0.8 ml per 100 g of body weight using peristaltic syringe pump. We applied the acupressure with a pressure oscillator to tail as a control and 2 different acupoints of sobu(HT8), youngchun(KI1) under 3 different conditions : 1) normal arterial blood pressure without bleeding, 2) at the beginning of bleeding, and finally 3) hemorrhagic shock. Results : Under normal arterial blood pressure without hemorrhage, there was a significant increase in systolic and diastolic blood pressures by the acupressure to the tail, HT8 and especially KI1 for 30 sec compared with before acupressure. Under hemorrhagic shock condition, the tail acupressure had minimal changes in cardiovascular parameters. Either the HT8 or KI1 acupressure resulted in a significant increase in arterial pressure but did not heart rate. At the beginning of bleeding, tail acupressure failed to change the reduction of arterial pressure and heart rate. However, there was a significant increase in blood pressure and heart rate following either the HT8 or especially KI1 acupressure. Conclusions : HT8 and KI1 acupressure affected cardiovascular signs but tail acupressure did not in rat model of hemorrhagic shock. These experimental data suggest that a acupressure with a pressure oscillator to HT8 or KI1 can be one of alternative emergency manipulations to ameliorate compromised cardiovascular functions under hemorrhagic shock condition.

Artifacts and Conditions for Attribution of Responsibility (인공물과 책임귀속 조건)

  • Kim, Nam-ho
    • Journal of Korean Philosophical Society
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    • v.147
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    • pp.59-76
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    • 2018
  • What are the conditions make a being x a moral agent? Can an artifact be moral agent? A moral agent is considered to be a rational being capable of distinguishing between right and wrong. This study critically analyzed Davidson's position on the condition of the rational being and argued that the network of beliefs with propositional attitude and the beliefs as their background cannot be a requisite for the rational being. Later, it proves that the conditions proposed by $Proke{\check{s}}ov{\acute{a}}$ are merely paratactically listed superficial elements. The moral agent in this study includes the rational agent and it is proven that the strong first person viewpoint is the necessary and sufficient condition for rational agent and moral agent. In conclusion, it suggested a the sketch of moderate skepticism which sets the tentative limit on the agent potential in an artifact by suggesting conditions for moral agent instead of intense skepticism that strongly denies the potential as the moral agent.

Rail Corrugation Effects on the Dynamic Behavior of Clips of Rail Fastening System in Operation Environment of Urban Railway (도시철도 운영환경에서 파상마모에 의한 레일체결장치 클립의 진동 특성)

  • Kim, Man-Cheol;You, Won-Hee;Sim, Hyoung-Bo
    • Journal of the Korean Society for Railway
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    • v.19 no.4
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    • pp.489-497
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    • 2016
  • The rail fastening system, which provides a structural connection between the rail and the sleepers, is a main track component that plays an important role in retaining the rail gauge within acceptable tolerances, as well as in passing the train load to the roadbed through the sleepers. In this paper, a modal test was first performed to evaluate the dynamic characteristics (e.g., natural frequency) of the clips of the railway fastening system under the condition of rail corrugation in urban railway operation. The corrugation-induced passing frequency was then compared with the natural frequency of the clips to investigate any resonance effect during train passage. Furthermore, a field test under train passage was conducted to measure the accelerations on the rail and the rail fastening clips as well as the strains on the rail fastening clips in the rail corrugation condition. The field measurements indicated that the accelerations on the rail and the rail fastening clips have a close relationship with the rail corrugation, but they had a minimal effect on the strains of the rail fastening clips.

Controlling Low Frequency Instability in Hybrid Rocket Combustion With Swirl Injection and Fuel Insert (스월 분사와 삽입연료에 의한 하이브리드 로켓 연소의 저주파수 연소불안정 조절)

  • Hyun, Wonjeong;Lee, Chanjin
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.49 no.2
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    • pp.139-146
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    • 2021
  • In hybrid rocket combustion, the oxidizer swirl injection is frequently used to stabilize the combustion as the rotational velocity component affects the boundary layer flow. However, as the swirl strength increases, a problem arises where the combustion performance changes too much. Thus, this study attempts to control the low frequency instability while minimizing the change in combustion performance by adapting attenuated swirl injection with fuel insert used in reference [7]. To this end, a series of experimental tests were performed by varying swirl intensity and the location of the fuel insert. In the tests, the occurrence of combustion instability and combustion performance were closely monitored. The results confirmed that combustion instability was successfully suppressed at the condition of the swirl angle 6 degree and the location of fuel insert 310 mm. And, the changes in combustion pressure, O/F ratio, and fuel regression rate were found as minimal compared to the baseline case. Also the results reconfirmed that the formation of positive coupling between two high frequency oscillations in 500 Hz band, combustion pressure(p') and heat release oscillation(q'), is the necessary and sufficient condition of the occurrence of low frequency instability.

The alternative Method to Finish Modular Exponentiation and Point Multiplication Processes

  • Somsuk, Kritsanapong
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.15 no.7
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    • pp.2610-2630
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    • 2021
  • The aim of this paper is to propose the alternative algorithm to finish the process in public key cryptography. In general, the proposed method can be selected to finish both of modular exponentiation and point multiplication. Although this method is not the best method in all cases, it may be the most efficient method when the condition responds well to this approach. Assuming that the binary system of the exponent or the multiplier is considered and it is divided into groups, the binary system is in excellent condition when the number of groups is small. Each group is generated from a number of 0 that is adjacent to each other. The main idea behind the proposed method is to convert the exponent or the multiplier as the subtraction between two integers. For these integers, it is impossible that the bit which is equal to 1 will be assigned in the same position. The experiment is split into two sections. The first section is an experiment to examine the modular exponentiation. The results demonstrate that the cost of completing the modular multiplication is decreased if the number of groups is very small. In tables 7 - 9, four modular multiplications are required when there is one group, although number of bits which are equal to 0 in each table is different. The second component is the experiment to examine the point multiplication process in Elliptic Curves Cryptography. The findings demonstrate that if the number of groups is small, the costs to compute point additions are low. In tables 10 - 12, assigning one group is appeared, number of point addition is one when the multiplier of a point is an even number. However, three-point additions are required when the multiplier is an odd number. As a result, the proposed method is an alternative way that should be used when the number of groups is minimal in order to save the costs.