• 제목/요약/키워드: minor loss

검색결과 187건 처리시간 0.026초

피스톤크라운의 열간단조공정 최적화를 위한 유한요소해석 (FEM Analysis for Optimization of Hot Forging Process of Piston Crown)

  • 민규영;임성주;최호준;최석우;박용복
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 2009년도 춘계학술대회 논문집
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    • pp.98-101
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    • 2009
  • Piston crown to the hot forge a unified nature of the product has a shape with multi-level step forging process, so if you are not a mechanical process that can be a significant loss is material. Therefore, minor in terms of material technology; continue to improve the collection rate should be. The Piston crown and the manufacturing of products such as marine diesel engines, reducing costs and to improve mechanical properties of the method are being forged. Piston crown molding hot forging process the large volume forging products handling because of the size of the size of the hard plastic material flow process for improving the design and actual field experience through advanced plastic technology, and it is important to interpret the results and for many experimental plastic The accumulation of results is very important.

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Brachial Plexus Injury as a Complication after Nerve Block or Vessel Puncture

  • Kim, Hyun Jung;Park, Sang Hyun;Shin, Hye Young;Choi, Yun Suk
    • The Korean Journal of Pain
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    • 제27권3호
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    • pp.210-218
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    • 2014
  • Brachial plexus injury is a potential complication of a brachial plexus block or vessel puncture. It results from direct needle trauma, neurotoxicity of injection agents and hematoma formation. The neurological presentation may range from minor transient pain to severe sensory disturbance or motor loss with poor recovery. The management includes conservative treatment and surgical exploration. Especially if a hematoma forms, it should be removed promptly. Comprehensive knowledge of anatomy and adept skills are crucial to avoid nerve injuries. Whenever possible, the patient should not be heavily sedated and should be encouraged to immediately inform the doctor of any experience of numbness/paresthesia during the nerve block or vessel puncture.

하이브리드탄의 항력 및 유동해석 (A Drag and Flow Characteristics around the Hybrid Projectile)

  • 이상길;이동현
    • 한국군사과학기술학회지
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    • 제3권2호
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    • pp.23-34
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    • 2000
  • Three dimensional, compressible, mass weighted averaging of Favre, Navier-Stokes system with k-$\varepsilon$ turbulence, is numerically discretized to compute three dimensional multiple jet interaction flow fields for a hybrid projectile containing three rocket motors in the ogive section. Numerical flow field computations have been made for angled nose jets and rockets at supersonic speed using multiblock structured grid. The jet conditions include very high jet to free stream pressure ratio and high temperature. It is shown that the strength of nozzle stagnation pressure affects the flow field near the side nozzle and the high stagnation pressure increases total amount of drag by a few percent. However, minor drag loss due to the pressure drag might be fully overcomed by an additional axial thrust. The results of present study can be applied for the design of future hybrid projectile.

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Magnetic Characterization of the Nd Based Permanent Magnet by Newly-Developed Bipolar Pulse-Type Hysteresis Loop Tracer

  • Rhee, J.R.
    • Journal of Magnetics
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    • 제4권3호
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    • pp.73-75
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    • 1999
  • By appliying an slternate pulsed magnetic field -generated by using a sequential ignition circuit and a magnet exciting circuit- with peak value of about 10 T to the rod type Nd based magnet Nd2Fe12.7Cr1.3B with length of 5 mm and diameter of 3.6 mm, the basic magnetic properties such as saturation magnetization, residual magnetization, coercivity, maximum energy products, magnetic anisotropy and anisotropic field are investigated with obtaining the major and minor J-H loops of the magnet. The increase in coercivity due to eddy currents in ac measurement of coercivity is calculated considering eddy current loss by analyzing a wave of generating magnetic field. The average coercivity calculated for the magnet is about 12.2 kOe, anisotropy magnetic field and anisotropic constant are measured as 60 kOe 2.43 Mj/$m^3$, respectively.

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첨가율에 의한 Ni-Zn 페라이트의 소결특성에 관한 연구 (A Study on the Sintering Characteristics of Ni-Zn Ferrites with Additives)

  • 강재덕;문현욱;정병두;소대화
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1990년도 추계학술대회 논문집
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    • pp.71-77
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    • 1990
  • This paper is studied on the sintering characteristics of Ni-Zn ferrites. The specimen ferrites was composed of 20 mol% NiO, 30mol% ZnO, 50 mol% Fe$_2$O$_3$, and 0.0025 mol%, 0.005 mol%, 0.01 mol% Nb$_2$O$\_$5/, Bi$_2$O$_3$, V$_2$O$\_$5/, wee used as minor additives. Sintering was carried out at 1100$^{\circ}C$. As results from the experiments, the high value of initial permeability of 6X10$^2$∼9X10$^2$ can be achieved at 500KHz∼1000KHz. The value of loss factor 1X10 ̄$^2$∼2X10$^2$ can be achieved at 500KHz∼1000KHz. The lowest 1/(${\mu}$XQ) value was obtained in the specimen with the addition of 0.005mol% fracyion for V$_2$O$\_$5/.

Update on Health-related Quality of Life in Colorectal Cancer Patients

  • Young-Seok Cho
    • Journal of Digestive Cancer Research
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    • 제3권2호
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    • pp.70-75
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    • 2015
  • Along with the recent trend of improved survival in patients with colorectal cancer (CRC), health-related quality of life (HRQoL) has become a significant outcome measure and its improvement is an important goal. The most widely adopted CRC specific HRQoL questionnaires are the European Organization for Research and Treatment of Cancer Qualityof-Life Questionnaire (EORTC QLQ-CR38) and the Functional Assessment of Cancer Therapy (FACT-C). CRC survivors without serious comorbidity or recurrence experience only minor deficits of overall HRQoL when compared to the general population. However, disease recurrence, progression, and more specific limitations, including weight loss, reduction in energy, and psychosocial problems like psychological distress and depression, could result in lower HRQoL. To improve HRQoL, further research is required to develop appropriate health education regarding lifestyle changes and personalized intervention strategies for CRC survivors.

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Reciprocating Wear Test of AISI 52100 Bearing Steel in h-BN-based Aqueous Lubricants

  • Gowtham Balasubramaniam;Dae-Hyun Cho
    • Tribology and Lubricants
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    • 제39권6호
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    • pp.228-234
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    • 2023
  • In this study, reciprocating wear tests are performed on AISI 52100 bearing steel to investigate its tribological behavior in a hexagonal boron nitride (h-BN) water solution. The h-BN-based aqueous lubricant is prepared using an atoxic procedure called ultrasonic sonication in pure water. Ball-on-flat reciprocating sliding experiments are conducted, where the ball is slewed on a fixed flat at 50-㎛ displacement. The lubricating behavior of h-BN is compared with that of deionized (DI) water. Results show that the friction coefficient is higher in h-BN testing than that in DI tests, but the results are equalized as the friction coefficient reaches a stable level. Scanning electron microscopic images reveal significant material loss in the center and mild abrasion on the edge of the wear scar in h-BN tests. However, these effects are minor in DI water situations. The results of energy-dispersive X-ray spectroscopy show that considerable oxidation occurs in the central zone of the wear scar in h-BN cases with strong adhesion and material removal. These findings reveal the importance of determining ideal circumstances that can tolerate material friction and wear.

연포장재 필름으로 개별포장한 수삼의 저장조건에 따른 외관품질 변화 및 개체무게 감소 (Quality Change and Weight Loss of Fresh Ginseng Individually Packaged in a Soft Film According to its Storage Condition)

  • 손현주;김은희;이성계;노길봉
    • Journal of Ginseng Research
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    • 제25권3호
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    • pp.122-126
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    • 2001
  • 수삼을 물로 세척한 후 한 뿌리씩 연포장재 필름 주머니(ONY/LDPE/L-LDPE, 200$\times$300mm, 90$\mu\textrm{m}$)에 넣고 밀봉하여 $25^{\circ}C$, 1$0^{\circ}C$ 또는 4$^{\circ}C$에서 저장하면서 외관품질과 개체무게를 조사한 결과 수삼의 외관품질은 저장온도에 관계없이 주로 연화에 의하여 불량해졌으며 외관품질 변화 속도상수와 저장온도의 역수뿐만 아니라 개체무게 변화속도상수와 저장온도의 역수간에도 각각 5% 유의수준에서 양호한 직선관계를 나타내었다. 따라서 $25^{\circ}C$에서의 온도학대시험을 통하여 저온에서 저장중인 개별포장 수삼의 저장수명 및 개체무게 변화율을 단기간에 예측할 수 있을 것으로 판단된다.

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Feasibility Study on Styrofoam Layer Cushioning for Banana Bulk Transport in a Local Distribution System

  • Wasala, W.M.C.B.;Dharmasena, D.A.N.;Dissanayake, C.A.K.;Tilakarathne, B.M.K.S.
    • Journal of Biosystems Engineering
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    • 제40권4호
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    • pp.409-416
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    • 2015
  • Purpose: This study evaluates a new banana bulk packaging method under the real transport conditions of Sri Lanka. Methods: A field evaluation of optimized 8-mm thick Styrofoam sheets used as the cushioning material was applied. A trial transport was conducted from Thambuttegama to Colombo using a medium-sized open truck, with banana leaves as the control material. Data were recorded at the farmer, transporter, retailer, and consumer stages of the supply chain. Mechanical damage, physiological loss in weight, fruit firmness, total soluble solids, ripeness index, visual quality ratings, and the physical damage index of the bananas were measured at each stage. A cost-benefit analysis was also conducted for both packaging methods. Results: The 8-mm styrofoam sheets significantly reduced (p < 0.05) the mechanical damage from 26.3% to 12.9% compared to the conventional method for long-distance transport, and the physiological loss in weight showed a decrease of 2.88%. The loss of firmness of the fruits followed a simmilar pattern for both methods until reaching the retailer, but at the consumer was significantly higher (p < 0.05) for the control. However, the physical damage index at the retail stage for the control showed symptoms of physical injury, whereas the bananas transported using the cushioning materials exhibited only minor symptoms. Further, the visual quality of the fruits after transport from the farmer to the consumer was preserved, which is one of the main factors affecting consumer preference and retail price. The proposed method increases the profit margin by 51.2% for Embul bananas owing to the reduced postharvest losses. Conclusion: The 8-mm thick Styrofoam sheets reduced the physical damage to the bananas, with the quality parameters maintained at the prefered level. Moreover, profits may be increased.

Efficacy and safety of intragastric balloon for obesity in Korea

  • Kwang Gyun Lee;Seung-Joo Nam;Hyuk Soon Choi;Hang Lak Lee;Jai Hoon Yoon;Chan Hyuk Park;Kyoung Oh Kim;Do Hoon Kim;Jung-Wook Kim;Won Sohn;Sung Hoon Jung
    • Clinical Endoscopy
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    • 제56권3호
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    • pp.333-339
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    • 2023
  • Background/Aims: Intragastric balloon (IGB) is the only available endoscopic bariatric and metabolic therapy in Korea. End-ball (Endalis) has the longest history of clinical use among the IGBs available in Korea. However, little clinical data on this system have been reported. In this study, we aimed to evaluate the efficacy and safety of End-ball in Korea. Methods: We performed a retrospective cohort study of patients who underwent IGB insertion (End-ball) from 2013 to 2019. Demographic and anthropometric data were collected. The efficacy and safety of IGB treatment were analyzed. Results: In total, 80 patients were included. Mean age was 33.7 years and 83.8% were female. Initial body mass index was 34.48±4.69 kg/m2. Body mass index reduction was 3.72±2.63 kg/m2 at the time of IGB removal. Percent of total body weight loss (%TBWL) was 10.76%±6.76%. Percentage excess body weight loss was 43.67%±27.59%. Most adverse events were minor, and 71.4% of participants showed nausea, vomiting, or abdominal pain. Conclusions: IGB treatment showed good efficacy and safety profile in Korean patients with obesity. In terms of %TBWL and percentage excess body weight loss, the efficacy was similar to that in the Western population.