• 열처리공학회지
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• 제19권5호
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• pp.262-269
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• 2006

The development of eco-friendly low pressure carburizing system with high pressure gas quenching(LPC-GQ, 500kg/charge) led to new stage in the fundamental case-hardening treatments. This is due to its ability to provide tighter tolerances on the carburizing process with notable reductions in distortion of the carburized and hardened workpiece. This system is characteristics by high uniformity and reproducibility of heat treatment results, absence of an intergranular oxidation layer, carburizing of complex shapes, reduced cycle time, low operating costs, simplified production, eliminate post washing, and reduced grinding costs.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2012년도 추계학술대회 논문집
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• pp.33-34
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• 2012

• 한국진공학회:학술대회논문집
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• 한국진공학회 2012년도 제43회 하계 정기 학술대회 초록집
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• pp.268-268
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• 2012

Atmospheric pressure microwave induced plasmas are used to excite and ionize chemical species for elemental analysis, for plasma reforming, and for plasma surface treatment. Microwave plasma differs significantly from other plasmas and has several interesting properties. For example, the electron density is higher in microwave plasma than in radio-frequency (RF) or direct current (DC) plasma. Several types of radical species with high density are generated under high electron density, so the reactivity of microwave plasma is expected to be very high [1]. Therefore, useful applications of atmospheric pressure microwave plasmas are expected. The surface characteristics of SUS304 stainless steel are investigated before and after surface modification by microwave plasma under atmospheric pressure conditions. The plasma device was operated by power sources with microwave frequency. We used a device based on a coaxial transmission line resonator (CTLR). The atmospheric pressure plasma jet (APPJ) in the case of microwave frequency (880 MHz) used Ar as plasma gas [2]. Typical microwave Pw was 3-10 W. To determine the optimal processing conditions, the surface treatment experiments were performed using various values of Pw (3-10 W), treatment time (5-120 s), and ratios of mixture gas (hydrogen peroxide). Torch-to-sample distance was fixed at the plasma edge point. Plasma treatment of a stainless steel plate significantly affected the wettability, contact angle (CA), and free energy (mJ/$m^2$) of the SUS304 surface. CA and ${\gamma}$ were analyzed. The optimal surface modification parameters to modify were a power of 10 W, a treatment time of 45 s, and a hydrogen peroxide content of 0.6 wt% [3]. Under these processing conditions, a CA of just $9.8^{\circ}$ was obtained. As CA decreased, wettability increased; i.e. the surface changed from hydrophobic to hydrophilic. From these results, 10 W power and 45 s treatment time are the best values to minimize CA and maximize ${\gamma}$.

• Journal of Microbiology and Biotechnology
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• 제29권8호
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• pp.1240-1247
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• 2019

This study was conducted to examine the inactivation effect of the combined treatment of high hydrostatic pressure (HHP; 400 MPa for 1, 3, and 5 min) and cationic surfactant washing (0.05% benzethonium chloride, BEC) against Listeria monocytogenes inoculated on fresh-cut broccoli (FCB). Washing with BEC at concentrations exceeding 0.05% resulted in 2.3 log-reduction of L. monocytogenes counts on FCB, whereas HHP treatment had approximately 5.5-5.6 log-reductions regardless of the treatment time. Scanning electron microscopy corroborated microbial enumeration, revealing that the combined treatment was more effective in removing L. monocytogenes from FCB than individual treatment with HHP or BEC. Color and total glucosinolate content were maintained after the combined treatment, although the hardness of the FCB slightly decreased. The results clearly suggest that the combined treatment of HHP and BEC washing has potential value as a new sanitization method to improve the microbial safety of FCB.

• 한국기계가공학회지
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• 제18권8호
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• pp.67-73
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• 2019

An ultra-high pressure treatment device is a device used for increasing the shelf life of food by sterilizing it by applying hydrostatic pressure to solid or liquid food. The ultrahigh pressure treatment system developed in this study is a pressure vessel with a processing capacity of 100 L and a maximum pressure of 700 MPa. Pressure vessels for ultrahigh-pressure processing equipment are manufactured using wire-winding techniques. The design formula for making ultra-high pressure vessels with wire windings is given in ASME Section VIII - Division 3. In this study, the ratio of the cylinder to the winding area that can be applied in a wire-winding application was analyzed using a finite element analysis. Furthermore, the relationship between the variation of the residual stress in the vessel and the ratio of the winding area due to the variation of the winding tension was analyzed, and a design guide applicable to the actual product design was developed. Finally, the design equation was modified by presenting the coefficients to correct the difference between the finite element analysis and the design equation.

• Journal of Preventive Medicine and Public Health
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• 제41권4호
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• pp.255-264
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• 2008

Objectives: This study adopted a qualitative method to explore the layman's beliefs and experience concerning high blood pressure and its management in order to develop a strategy to increase adherence to proper medical treatment. Methods: Semi-structured interviews that focused on personal experiences with hypertension and its management were conducted with 26 hypertensive patients. The participants were selected according to a BP above 140/90 mmHg (hypertension stage 1), based on the seventh report of the Joint National Committee on prevention, detection, evaluation and treatment of high blood pressure (JNC-VII). The interviews lasted for approximately 30 minutes (range: 20-60 minutes). The resulting questions were formulated into open-ended questions. The interview questionnaire was composed 17 items to examine non-adherence to treatment and 19 items to examine adherence to treatment. Results: Most participants recognized that the direct cause of high blood pressure was unhealthy behavior rather than inheritance. Thus, the hypertensive patient believed they could recover their blood pressure to a normal level through removing the direct cause of hypertension (weight reduction, diet, exercise) instead of taking drugs. The reasons for these statements were that the drugs for controlling hypertension are not natural or they are artificial, and they may have side effects, and drugs are not treatment for the root cause of hypertension. Most of the hypertensive patients chose to manage their behaviors as soon as they knew their blood pressure was high. Therefore, we should not divide the subjects into two groups according to their taking drugs or not, but they should be divided into two groups according to their willingness or not to manage their condition. Conclusions: For developing a strategy for an individual approach to hypertension management, we need to develop a client-centered attitude and strategy. That is, we need to tailor our approach to individual cases to avoid generalizations and stereotyping when developing an adherence increasing strategy.

• Archives of Plastic Surgery
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• 제34권2호
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• pp.269-273
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• 2007

Purpose: High-pressure injection(HPI) injury is an injury caused by accidental injection of substances by industrial equipment. HPI injury of the hand is a serious injury that can be potentially devastating. There have been a number of publications on the results of its treatment and its functional outcome of these hands. Unfortunately, the clinical outcomes were unsatisfactory following an initial treatment approach of digital expression of the injection material, elevation, soaks, dressing changes, and antibiotics. Methods: A 43-year-old right handed man sustained a high pressure injection injury to the tip of the left index finger. The injected material was industrial paint thinner. Tissue necrosis was noted at the pulp of the finger. Several debridements and irrigation were required. A pedicled chest flap transfer was performed on the eighteenth day after injury as the dorsal nail complex remained viable. This is a retrospective review of our experience with high-pressure finger injection injury caused by paint. A literature review, retrospective chart and radiologic review were presented. Results: Follow-up length was about 1 year. The injuried hand was left nondominant hand, the index. Patient complaints were cold intolerance, paresthesia, contact pain, and impairment of activities of daily living. Conclusion: The outcome of high-pressure injection injuries of the hand is affected by many factors. The time between injury and operative treatment has been regarded as a key determinant by a number of authors. The nature of the injected material is probably more important. It has been noted by many authors that injuries with paints have a worse outcome than those with oil or grease. This study confirms the fact that high-pressure injection injury caused by paint thinner to the hand is a significant problem. Virtually a patient suffers sequelae of this injury. The injury has significant repercussions for future function and reintegration into the work force.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2001년도 제22회 KOSCI SYMPOSIUM 논문집
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• pp.106-118
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• 2001

A rigorous study of single droplet vaporization under quiescent high pressure atmosphere is attempted adopting method of flash evaporation calculation for vapor-liquid equilibrium. Results due to flash method shows excellent agreement with measurement. Also shown is the present model fairly capable of depicting transients of droplet vaporization under high pressure environment, such as ambient gas solubility, property variation, and multicomponent transports. Systematic treatment of these effects with emphasis on vapor-liquid phase equilibrium revealed; conventional treatment for subcritical droplet vaporization, such as $d^2$-law, leads to erroneous prediction of droplet history, augmented gas solubility is significant under supercritical pressure, and vaporization rate proportionally increase with pressure.

• Archives of Plastic Surgery
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• 제44권4호
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• pp.276-282
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• 2017

Perioperative hypertension is a phenomenon in which a surgical patient's blood pressure temporarily increases throughout the preoperative and postoperative periods and remains high until the patient's condition stabilizes. This phenomenon requires immediate treatment not only because it is observed in a majority of patients who are not diagnosed with high blood pressure, but also because occurs in patients with underlying essential hypertension who show a sharp increase in their blood pressure. The most common complication following facelift surgery is hematoma, and the most critical risk factor that causes hematoma is elevated systolic blood pressure. In general, a systolic blood pressure goal of <150 mm Hg and a diastolic blood pressure goal of >65 mm Hg are recommended. This article discusses the causes of increased blood pressure and the treatment methods for perioperative hypertension during the preoperative, intraoperative, and postoperative periods, in order to find ways to maintain normal blood pressure in patients during surgery. Further, in this paper, we review the causes of perioperative hypertension, such as anxiety, epinephrine, pain, and postoperative nausea and vomiting. The treatment methods for perioperative hypertension are analyzed according to the following 3 operative periods, with a review of the characteristics and interactions of each drug: preoperative antihypertensive medicine (atenolol, clonidine, and nifedipine), intraoperative intravenous (IV) hypnotics (propofol, midazolam, ketamine, and dexmedetomidine), and postoperative antiemetic medicine (metoclopramide and ondansetron). This article focuses on the knowledge necessary to safely apply local anesthesia with IV hypnotics during facelift surgery without the assistance of an anesthesiologist.

• 한국축산식품학회지
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• 제33권1호
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• pp.16-23
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• 2013

This study was carried out to investigate the effect of trans-cinnamaldehyde and high pressure treatment on milk. Cinnamon oil milk was manufactured by high speed homogenization (3,000 rpm) and high pressure homogenization (500 and 2,000 bar) processing UHT milk and trans-cinnamaldehyde of various concentrations (0 to 0.1% (w/v)). Cinnamon oil milk was inoculated with Escherichia coli (6.4 Log CFU/mL) and kept at $7^{\circ}C$ for 10 d to observe the antibacterial effect. The cinnamon oil milk containing 0.05% (w/v) trans-cinnamaldehyde initially began to show an antibacterial effect and Escherichia coli completely died in cinnamon oil milk added 0.1% (w/v) trans-cinnamaldehyde on the 6th day of storage. The result of the TBA value showed that the addition of 0.1% (w/v) trans-cinnamaldehyde was also effective to protect lipid oxidation. In the physical properties of cinnamon oil milk, particle sizes were enlarged in all samples during storage periods and the total color difference of cinnamon oil milk was slightly increased as level of high pressure. The surface tension of cinnamon oil milk treated 2,000 bar was remarkably higher than other samples. It seems that trans-cinnamaldehyde showed antibacterial activity and antioxidation effect at 0.05 and 0.1% (w/v) of concentration. Remarkably, high pressure treatment did not influence its microbial property but slightly affected the physical properties of cinnamon oil milk.