• Title/Summary/Keyword: volume control method

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Developing a Program Performance Management Framework for Mixed-use Development in Urban Regeneration Projects (입체복합공간 개발사업의 프로그램 성과관리 체계 구축)

  • Lee, Kang-Wook;Hong, Hwa-Uk;Park, Hee-Dae;Han, Seung-Heon
    • Korean Journal of Construction Engineering and Management
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    • v.12 no.1
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    • pp.141-152
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    • 2011
  • The market volume of urban regeneration projects has steadily increased, thereby mixed-use development also shows significant market growth. However, previous researches on urban regeneration mainly deduced suggestions and plans for institution improvement based on comparison between projects implemented the inside and outside of the country. Whereas, researches on project management closely related to project success were limited, particularly in performance management. Accordingly, this research aims at developing a program performance management framework for public clients so as to succeed mixed-use development projects. Through extensive literature review and expert interview, this research developed performance indices for diverse facilities, risk management framework and integrating method of program performance score. The proposed framework is able to consider total life cycle from basic planning to maintenance phase and to check real-time performance level. Moreover, risk management framework can periodically assess and control the level of inherent risks within performance indices. The results can contribute to improve existing performance management practices and be basis for a web-based system developed in future.

Effect of fuel injection timing and pressure on the combustion and spray behavior characteristics of diesel fuel for naval vessel (연료분사시기와 압력이 함정용 디젤연료의 분무 및 연소특성에 미치는 영향)

  • Lee, Hyung-min
    • Journal of Advanced Marine Engineering and Technology
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    • v.39 no.9
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    • pp.911-917
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    • 2015
  • The objective of this work focuses on the analysis of injection rate and macroscopic spray behavior characteristics with injection pressures as well as combustion and exhaust emission characteristics with injection timing and injection pressure by using a common rail single-cylinder diesel engine. The injection rate was measured by applying the Bosch method, and macroscopic spray behavior characteristics were analyzed with a constant-volume vessel and a high-speed camera. In addition, combustion and emission characteristics were analyzed in a common-rail single-cylinder diesel engine with precise control of fuel injection timing and pressure. For injection pressures of 30MPa and 50MPa, the injection rate was higher at 50 MPa, and the spray development (penetration) was also higher in the same elapsed time. The peak in-cylinder pressure and rate of heat release showed a tendency to decline as injection timing was delayed, and the peak in-cylinder pressure and rate of heat release were slightly higher for higher injection pressures. Higher injection pressures also reduced the mean effective pressure, while the indicated mean effective pressure and torque increased as injection timing was delayed to TDC. Nitrogen oxides had a peak level at injection timings of $BTDC20^{\circ}$(30MPa) and $BTDC15^{\circ}$(50MPa); carbon monoxide emissions were reduced by delaying injection timing from $BTDC30^{\circ}$.

Development of Novel Assistive Device for Improving Usability of BVM (인공호흡기 사용성 향상을 위한 새로운 보조기구 개발)

  • Jeon, Gang-Hyun;Park, Yong-Jai
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.21 no.3
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    • pp.420-426
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    • 2020
  • In this study, an assistive device for BVM (Bag Valve Mask) was developed. When emergencies occur, rescuers must perform artificial respiration within four minutes utilizing suitable BVM. If not, the patient can suffer serious damage within their brain and body systems. The rescuer must execute artificial respiration until the patient arrives at the hospital. In the process of artificial respiration, the rescuer can feel fatigued in their forearm muscles, particularly those who may have smaller hands or weaker muscle strength. Many products have been developed to solve these problems, but these products are difficult to market and commercialize because of their volume, size, and difficulty of use. In this paper, the BVM assistive device that has been previously manufactured was improved, and an attempt was made to devise a new method that reduces the burden on the user. The BVM assistive device can be divided into three-parts: a head part for compressing the air bag, which can control the amount of air; the body part for coupling with BVM; and finally, the handle that can rotate for better use on various postures of patients. Throughout the experiment, the assistive device could inject an equal amount of air into the patients. As a result, the rescuer could feel less fatigue and inject a suitable amount of air to emergency patients during artificial respiration.

The Effect of Barrel Vibration Intensity to the Plating Thickness Distribution

  • Lee, Jun-Ho;Roselle D. Llido
    • Proceedings of the Korean Institute of Surface Engineering Conference
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    • 1999.10a
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    • pp.15-15
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    • 1999
  • In chip plating, several parameters must be taken into consideration. Current density, solution concentration, pH, solution temperature, components volume, chip and media ratio, barrel geometrical shape were most likely found to have an effect to the process yields. The 3 types of barrels utilized in chip plating industry are the conventional rotating barrel. vibrational barrel (vibarrel), and the centrifugal type. Conventional rotating barrel is a close type and is commonly used. The components inside the barrel are circulated by the barrel's rotation at a horizontal axis. Process yield has known to have higher thickness deviation. The vibrational barrel is an open type which offers a wide exposure to electrolyte resulting to a stable thickness deviation. It rotates in a vertical axis coupled with multi-vibration action to facilitate mixed up and easy transportation of components, The centrifugal barrel has its plated work centrifugally compacted against the cathode ring for superior electrical contact with simultaneous rotary motion. This experiment has determined the effect of barrel vibration intensity to the plating thickness distribution. The procedures carried out in the experiment involved the overall plating process., cleaning, rinse, Nickel plating, Tin-Lead plating. Plating time was adjusted to meet the required specification. All other parameters were maintained constant. Two trials were performed to confirm the consistency of the result. The thickness data of the experiment conducted showed that the average mean value obtained from higher vibrational intensity is nearer to the standard mean. The distribution curve shown has a narrower specification limits and it has a reduced variation around the target value, Generally, intensity control in vi-barrel facilitates mixed up and easy transportation of components, However, it is desirable to maintain an optimum vibration intensity to prevent solution intrusion into the chips' internal electrode. A cathodic reaction can occur in the interface of the external and internal electrode. $2HD{\;}+{\;}e{\;}{\rightarrow}20H{\;}+{\;}H_2$ Hydrogen can penetrate into the body and create pressure which can cause cracks. At high intensity, the chip's motion becomes stronger, its contact between each other is delayed and so plating action is being controlled. However, the strong impact created by its collision can damage the external electrode's structure thereby resulting to bad plating condition. 1 lot of chip was divided into two equal partion. Each portion was loaded to the same barrel one after the other. Nickel plating and tin-lead plating was performed in the same station. Portion A maintained the normal barrel vibration intensity and portion B vibration intensity was increased two steps higher. All other parameters, current, solution condition were maintained constant. Generally, plating method find procedures were carried out in a best way to maintained the best plating condition. After plating, samples were taken out from each portion. molded and polished. Plating thickness was investigated for both. To check consistency of results. 2nd trial was done now using different lot of another characteristics.

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Infusion Methods for Continuous Interscalene Brachial Plexus Block for Postoperative Pain Control after Arthroscopic Rotator Cuff Repair

  • Byeon, Gyeong Jo;Shin, Sang Wook;Yoon, Ji Uk;Kim, Eun Jung;Baek, Seung Hoon;Ri, Hyun Su
    • The Korean Journal of Pain
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    • v.28 no.3
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    • pp.210-216
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    • 2015
  • Background: Infusion methods during regional analgesia using perineural catheters may influence the quality of postoperative analgesia. This study was conducted to compare the effects of combined or bolus-only infusion of 0.2% ropivacaine on the postoperative analgesia in interscalene brachial plexus block (ISBPB) with perineural catheterization. Methods: Patients scheduled for arthroscopic rotator cuff repair were divided into two groups, one that would receive a combined infusion (group C, n = 32), and one that would receive intermittent infusion (group I, n = 32). A perineural catheter was inserted into the interscalene brachial plexus (ISBP) using ultrasound (US) and nerve stimulation, and 10 ml of 0.2% ropivacaine was administered. After the operation, group C received a continuous infusion of 4 ml/h, and a 4 ml bolus with a lockout interval of 60 min. Group I received only a 4 ml bolus, and the lockout interval was 30 min. Postoperative pain by the numeric rating scale (NRS) and the forearm muscle tone by the manual muscle test (MMT) were checked and evaluated at the following timepoints: preoperative, and postoperative 1, 4, 12, 24, 36, and 48 h. Supplemental opioid requirements, total consumed dose of local anesthetic, and adverse effects were compared between the two groups. Results: Sixty-four patients completed the study and the postoperative values such as operation time, time to discharge, and operation site were comparable. There were no differences in NRS scores and supplemental opioid requirements between the two groups. The MMT scores of group I at 4 and 12 h after surgery were significantly higher than those of group C (P < 0.05). The total consumed dose of local anesthetic was significantly lower in group I than in group C (P < 0.05). The adverse effects were not different between the groups. Conclusions: The bolus-only administration of 0.2% ropivacaine provided a similar analgesic effect with a lower total volume of local anesthetic and decreased motor weakness compared to combined infusion. Therefore, bolus-only administration is an effective postoperative analgesic method in ISBPB with perineural catheterization after rotator cuff repair.

A Study on the Development of a Dam Operation Table Using the Rainfall Matrix (강우 매트릭스를 활용한 댐 운영 조견표 개발에 관한 연구)

  • Jeong, Changsam
    • Journal of Korean Society of Disaster and Security
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    • v.13 no.2
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    • pp.39-51
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    • 2020
  • Recently, flood damage has been increasing in Korea due to frequent local torrential rains caused by abnormal weather conditions. According to the calculation of the recurrence period of torrential rain that occurred in North Chungcheong Province on July 16, 2017, it was estimated that the rainfall frequency in the upper are of Goessan Dam was around 1,524 years, and the highest level of Goesan Dam rose to EL.137.60 meters, leaving only 5 cm of margin until the height of the dam floor (EL.137.65 meters). The Goesan Dam, which operated for 62 years since 1957, needs to be prepared to cope with the increase of floodgate volume in the basin, the development of a single purpose dam for power generation only, and there are no measurement facilities for flood control, so efficient operation methods are needed to secure the safety of residents in upper and lower regions. In this study, a method of dam operation was proposed by constructing a rain matrix for quick decision making in flood prediction, calculating the highest level of dam for each condition in advance, and preparing a survey table, and quickly finding the level corresponding to the conditions in case of a situation.

Platelet Rich Plasma Injection: Evidence Based Analysis (혈소판 풍부 혈장 주사 요법: 근거 중심의 분석)

  • Oh, Joo Han;Chung, Seok Won
    • The Journal of Korean Orthopaedic Ultrasound Society
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    • v.4 no.2
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    • pp.111-122
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    • 2011
  • Platelet rich plasma (PRP) has been widely used nowadays for several common orthopaedic-related sports medicine conditions with the theoretical basis that PRP supplies numerous autologous growth factors from concentrated platelets needed to promote the healing process of injured tissue. Even though there are many basic sciences, animal studies and some clinical studies regarding PRP injections for musculoskeletal injuries which suggested good results, it is difficult to compare these various studies due to marked methodological differences such as PRP preparation method, the timing, volume and number of injection, and the outcome measurement tool. In addition, many studies have no control groups or a limited sample size, and there are few prospective randomized controlled trials assessing the efficacy of PRP injections. Therefore, well designed high-quality randomized studies are required to confirm the preliminary results until now and provide scientific evidence to support its use, and the paucity of scientific clinical evidence suggest that the administration of PRP on humans for musculoskeletal injuries should be performed with caution.

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The Effect of Therapy Oriented CT in Radiation Therapy Planning (치료 계획용 전산화 단층촬영이 방사선 치료계획에 미치는 효과)

  • Kim, Sung-Kyu;Shin, Sei-One;Kim, Myung-Se
    • Radiation Oncology Journal
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    • v.5 no.2
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    • pp.149-155
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    • 1987
  • The success of radioation therapy depends on exact treatment of the tumor with significant high dose for maximizing local control and excluding the normal tissues for minimizing unwanted complications. To achieve these goals, correct estimation of target volume in three dimension, exact dose distribution in tumor and normal critical structures and correction of tissue inhomogeneity are required. The effect of therapy oriented CT (plannng CT) were compared with conventional simulation method in necessity of planning change, set dose, and proper distribution of tumor dose. Of 365 new patients examined, planning CT was performed in 104 patients $(28\%)$. Treatment planning was changed in $47\%$ of head and neck tumor, $79\%$ of intrathoracic tumor and $63\%$ of abdmonial tumor. in breast cancer and musculoskeletal tumors, planning CT was recommended for selection of adequate energy and calculation of exact dose to critical structures such as kidney or spinal cord. The average difference of tumor doses between CT planning and conventional simulation was $10\%$ in intrathoracic and intra-abdominal tumors but $20\%$ in head and neck tumors which suggested that tumor dose may be overestimated in conventional simulation Although some limitations and disadvantages including the cost and irradiation during CT are still criticizing, our study showed that CT Planning is very helpful in radiotherapy Planning.

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Appropriate Root-zone Temperature Control in Perlite Bag Culture of Tomato during Winter Season (저온기 토마토 펄라이트 자루재배시 최적 근권온도 조절 방법)

  • Kim, Sung-Eun;Sim, Sang-Youn;Lee, Sang-Don;Kim, Young-Shik
    • Horticultural Science & Technology
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    • v.28 no.5
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    • pp.783-789
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    • 2010
  • The effective method for heating root-zone during winter season was studied in the aspects of growth, yield and economics for tomato ($Solanum$ $lycopersicum$) in perlite bag culture. There were four root-zone heating treatments: two hours heating from one hour before to one hour after sunrise, four hours from two hours before to two hours after sunrise, 15 hours after sunset, and no heating. The growth characteristics of the upper parts of plants were not significantly different among the treatments, but root volume increased with longer heating of the root zone. The Plant Development Index, using stem diameter and the length between growing tip and the upper flowering truss, showed relation between yield per cluster and growth pattern. The treatment heating for four hours was the most economic in terms of growth and yield of tomato.

A Study on Self-Esteem and Urinary Symptoms in Women with Urinary Incontinence (요실금환자의 골반근육운동에 따른 자아존중감과 배뇨증상에 관한 연구)

  • Lee Young-Hee;Kim Sun-Are
    • Journal of Korean Academy of Fundamentals of Nursing
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    • v.9 no.3
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    • pp.360-369
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    • 2002
  • Purpose: The purpose of this study was to help enhance the quality of life for women with urinary incontinence. Self-esteem, urinary symptoms, peak pressure and duration in seconds for vaginal contraction after pelvic muscles exercise were examined. Method: One-group pretest-posttest design was employed participants were 27 married women from G city. The instrument for this study were : the self-esteem scale developed by Rosenberg(1965). the Urinary Symptom Questionnaire, a subjective measurement of urinary incontinence, developed by Jackson et al.(1996) and the Perineometer used as an objective measurement of peak pressure and duration in seconds. Result: 1. Self-esteem showed significant improvement after the exercise (t=-3.832, p= .001). 2. Comparison of results before the pelvic muscles exercise and after showed that there was a statistically significant difference for several urinary symptoms including enuresis (t=2.833, p=.009), frequency of incontinence (t=2.964, p= .006), incontinence volume (t=2.280, p= .031), incontinence before getting to the restroom (t=3.035, p= .006), incontinence with no reason or feeling (t= 3.051, p= 005) burning sensation (t= 2.132, p=.043), and a sense of residual urine (t=2.267 p=.032). The mean scores showed improvement in the urinary symptoms of management of incontinence (M=$0.04{\pm}0.22$), daily frequency of incontinence management (M=$0.13{\pm}0.85$), urinary control (M=$0.15{\pm}0.86$), running to the restroom (M=$0.15{\pm}0.60$) incontinence caused by coughing or physical activities (M=$0.19{\pm}0.57$) and hesitancy (M=$0.07{\pm}0.55$). Overall urinary symptoms decreased significantly (t =3.073. p= .007). 3. Peak pressure showed an increase from a mean of $24.26{\pm}16.20mmHg$ before the exercise to a mean of $28.63{\pm} 17.79mmHg$ after (t=-2.399, p=.024). Duration in seconds also increased from a mean of $6.00{\pm}4.95sec$ to $9.15{\pm}5.83sec$ (t=-4.400, p= 000). Conclusion: These findings suggest that pelvic muscle exercise serves to decrease urinary problems, improve self-esteem and increase peak pressure and duration in seconds.

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