• Title/Summary/Keyword: Burn Rate

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Optimal Burn-In under Waranty

  • Kim, Kui-Nam;Lee, Kwang-Ho
    • Communications for Statistical Applications and Methods
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    • v.6 no.3
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    • pp.719-728
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    • 1999
  • This paper discusses an optimal burn-in procedure to minimize total costs based on the assumption that the failure rate pattern follows a bimodal mixed Weibull distribution. The procedure will consider warranty period as a factor of the total expected burn-in cost. A cost model is formulated to find the optimal burn-in time that minimizes the expected burn-in cost. Conditional reliability for warranty period will be discussed. An illustrative example is included to show how to use the cost model in prctice.

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Effects of a Recreation Therapy Program on Mental Health and Heart Rate Variability in Burn Rehabilitation Patients (치료레크리에이션 프로그램이 화상재활환자의 정신건강 상태와 심박동 변이에 미치는 효과)

  • Kil, Myung-Sook;Lee, Mi-Hwa;Lee, Yong-Mi
    • Journal of Korean Biological Nursing Science
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    • v.17 no.2
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    • pp.179-187
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    • 2015
  • Purpose: This study was done to evaluate the effects of a recreation therapy program on burn rehabilitation patients to determine if the program is an effective nursing intervention which can affect mental health problems and heart rate variability. Methods: Subjects were 54 hospitalized burn rehabilitation patients (25 in the control group, 29 in the experimental group). The experimental group participated 6 times in a recreation therapy program led by a qualified instructor. Brief symptoms inventory-18 (somatization, anxiety, depression) questionnaire, and heart rate variability were checked before and after the recreation therapy program. Results: The mental health scale showed significant differences in somatization (p<.001), anxiety (p<.001) and depression (p<.001). There was no significant difference in heart rate variability (autonomic activity, autonomic balance, stress resistance, stress parameter and fatigue, mean heart rate, electro-cardiac stability). Conclusion: The findings from this study suggest that a recreation therapy program is an effective nursing intervention to decrease the level of mental health problems of burn rehabilitation patients. However, a subsequent study is needed to develop an intervention program that will induce the effect of physiological parameters like heart rate variability (HRV).

Percutaneous Absorption of Recombinant h-EGF through Normal, Stripped and First-Degree Burn Skin (상피세포 성장인자의 경피흡수: 정상피부, 각질제거피부 및 화상피부에 있어서)

  • Cho, Ae-Ri;Lee, Jung-Uk;Ahn, Byung-Lak;Chung, Joo-Young;Koh, Yeo-Wook;Shim, Chang-Koo
    • Journal of Pharmaceutical Investigation
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    • v.26 no.1
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    • pp.29-32
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    • 1996
  • In vivo and in vitro skin permeation of $recombinant^{125}$ I-EGF through normal, stripped and the first degree burn skin were studied. The in vitro skin permeation rate through the first degree burn skin $(296\;cpm/cm^2/hr)$ and the stripped skin $(1131\;cpm/cm^2/hr)$ were 3.5 times and 13 times higher, respectively, as compared with the one through normal skin. In vivo absorption study with the first degree burn skin, the peak concentration of EGF in the skin was achieved at 1-3 hr and decreased afterward up to 8 hr with an elimination constant of $1.31{\times}10^{-3}\;g/ml/hr$. To investigate the higher elimination rate of EGF in burn skin, binding and metabolism studies were conducted. No significant metabolism of EGF in burn skin $(100^{\circ}C,\;5-second\;burning)$ was observed. With the presence or unlabelled-EGF $^{125}I-EGF$ permeation through the burn skin showed higher permeation rate than the one without unlabelled-EGF. The result nay indicate that EGF-receptor binding play a role in determining the skin permeation rate.

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A study on expansion of lean burn limit with direct injection of the heavy-duty CNG engine (대형 CNG기관의 직접분사화에 의한 희박한계확장)

  • Park, Jung-Il;Chung, Chan-Moon;Noh, Ki-Chul;Lee, Jong-Tai
    • Proceedings of the KSME Conference
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    • 2007.05b
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    • pp.3282-3287
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    • 2007
  • Lean combustion is one of the most promising method for increasing engine efficiency and reducing the exhaust emission from SI gas engines. Due to the possibility of partial burn and misfire, however, under lean burn operation, stable flame kernel formation and fast burn rate are needed to guarantee a successful subsequent combustion. Experiment data were obtained on a single-cylinder CNG fueled SI engine to investigate the effect of direct injection, spark timing and variation of injection timing. Experimental results show that lean burn limit is ${\lambda}$=1.3 with port injection, and expansion of lean burn limit ${\lambda}$=1.4 with direct injection method, due to increase of turbulence intensity in cylinder and stratified charge. Combustion duration in lean region is improved by using the variation of injection timing.

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Povidone-Iodine related Chemical Burn under the Tourniquet (A Case Report) (지혈대 내측의 포비돈-요오드 용액에 의한 화학 화상 (1예 보고))

  • Won, Jong-Kyoung;Lee, Kang
    • Journal of Korean Foot and Ankle Society
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    • v.16 no.3
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    • pp.190-192
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    • 2012
  • In the extremity surgery, pneumatic tourniquet and povidone-iodine solution are commonly used to provide an aseptic, bloodless field, and their complication rate has remained low. However, chemical burn under tourniquet has been rarely reported. Patients sustained burn injuries over the dependent, weight-bearing regions such as posterior neck, back, buttocks and posterior thighs. This rare adverse complication occurred in a 22-year-old man who underwent modified Brostrom operation with arthroscopic os trigonum excision. 10% povidone-iodine was used as topical antiseptic, and full thickness burn occurred underneath the area of tourniquet application. Main causes of povidone-iodine related chemical burn are considered maceration, irritation of the skin, long term use of the tourniquet and pressure. To reduce the complications like chemical burn, awareness of the risk and the possible pathogenesis as well as the preventive measures is important in surgical practice.

Transdermal Drug Delivery & Therapeutic Effect of the Preparations of Lithospermi Radix and Gardeniae Fructus Extracts on the Burn & Wound Healing (화상 및 창상에 대한 자근.치자 복합제제의 경피 흡수 및 치료효과)

  • Min, Dong-Hoon;Kim, Dae-Keun;Lim, Jong-Pil;Yang, Jae-Heon
    • Journal of Pharmaceutical Investigation
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    • v.35 no.4
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    • pp.255-263
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    • 2005
  • Research was undertaken to compare the pharmacological activity of Lithospermi radix (LR) reported as an oriental medicine for classical uses. LR contains naphthoquinone pigments : shikonin, acetylshikonin, isobutylshikonin, etc. LR is used for the treatment of excision wound, burn, eczema, blister, scarlatina and septicemia as antifebrile, antidotic and antiphlogistic. Gardeniae fructus (GF) has been used for the treatment to jaundice, hepatic disease, anti-inflammatory and analgesic effects, and it contains crocin, geniposide and its derivatives. The therapeutic effects of burn and excision wound healing from LR & GF hydrogel with $Nano-ATP^{\circledR}$ (GLN) were investigated. To evaluate the therapeutic value of various hydrogels, thermal burn model and excision wound mouse model were used. The burn and wound reduction rate and therapeutic period were measured to calculate the healing extent after 5 experiments. The 2nd degree burn was prepared on hairless mouse back skin and dressing with collagen. The burn and wound reduction rate of GLN hydrogel treated group decreased more rapidly than that of other gel group in animal model. Furthermore therapeutic periods of GLN hydrogel treated group was shorter than that of other gel group. In anti-inflammatory test, GLN hydrogel treated group decreased edema rapidly than that of other gel group. These results suggest that the GLN hydrogel treatment has an therapeutic effect on burn and excision wound healing.

The Clinical Investigation of Necrotizing Fasciitis in Burn Center (화상센터에서 치료한 괴사성근막염의 임상적 고찰)

  • Kim, Euimyung;Chun, Jin Woo;Kim, Young Min;Yoon, Jae Chul;Lim, Hae Jun;Cho, Yong Suk;Kim, Dohern;Hur, Jun;Chun, Wook
    • Journal of the Korean Burn Society
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    • v.22 no.2
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    • pp.66-70
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    • 2019
  • Purpose: The necrotizing fasciitis is a terrifying infectious disease that can rapidly spreads to surrounding tissues when fascia is infected and it can cause sepsis to death if not properly diagnosed and treated. The purpose of this study is to investigate the characteristics, causes, and treatment methods of necrotizing fasciitis in Korea through reviewing patients admitted to our burn center. Methods: 21 patients with necrotizing fasciitis were selected for this study among those inpatients with electronic medical records (EMR) admitted to Hallym University Hangang Sacred Heart Medical Center from Jan 1, 2008 to June 30, 2019. The medical records and wound photos of those 21 selected subjects were reviewed. Results: There were 13 male and 8 female patients and mean age was 58.76 years old. 13 of 21 subjects were survived and 8 died (38% mortality rate). The surgical treatments performed were I&D, fasciotomy, debridement, allograft, burring, STSG, flap, and amputation. The most common causes were burns in 9 subjects (6 contact burns) and cellulitis occurred on skins in 5 subjects. And other various causes were observed as fournier's gangrene, stab wound, intramuscular injection, tumor and bleu toe syndrome (toe necrosis). The infected areas were 11 feet and legs, 7 hips, 3 abdomen and trunk in 21 subjects. Of the 8 deaths, 3 were infected in feet and legs, 2 were infected in hips, and 2 were infected in abdomen and trunk. As for underlying diseases, 12 patients with hypertension or diabetes were the highest and others such as cancer and stroke were found. Conclusion: The only method to increase the survival rate is to 'suspect' the disease as much as possible and perform early extensive excision. It is advisable to treat the disease by the burn center to properly provide adequate and optimal wound management, infection control, medical care and nutritional supports.

Epidemiologic Analysis of Burns in Military Hospital

  • Choi, Jangkyu;Park, Sejin;Kim, Hyun Chul
    • Journal of Trauma and Injury
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    • v.30 no.4
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    • pp.145-157
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    • 2017
  • Purpose: We accessed epidemioloy of 908 acute burns (7 years) in the military, of injuries and propose proper educational programs to suit community. Methods: We surveyed burn demographics, circumstances of injuries, size, result of treatment. Results: The mean age was 20.6 years. The flame burns (FB) (325, 35.8%) were most common, followed scald (SB) (305, 33.6%), contact (CB) (219, 24.1%), electric (EB) (45, 5.0%) and chemical burns (ChB) (14, 1.5%). The more occurred during winter (29.7%). SB had mean 3.9% total body surface area (TBSA). The 251 (82.3%) had superficial burns by spillage of hot water/food on lower limbs (45.6%), feet (33.8%) in summer (34.8%), treated with simple dressing (92.8%). Morbidity rate was 5.6%; post traumatic stress disease (PTSD) (0.7%). FB had large wound (9.3% TBSA). The 209 (64.3%) had superficial burns by ignition to flammable oils (31.7%) and bomb powders (29.2%) on head/neck (60.3%), hands (58.6%) in summer (31.7%), autumn (30.2%). They underwent simple dressing (83.4%) and skin graft (16.0%). Morbidity rate was 18.8%; PTSD (10.5%), inhalation injuries (4.0%), corneal injury (3.7%), amputations (0.9%), and mortality rate (1.2%). CB had small (1.1% TBSA), deep burns (78.5%) by hotpack (80.4%) on lower limbs (80.4%). The more (59.8%) underwent skin graft. EB had 6.8% TBSA. The 29 (64.4%) had superficial burns by touching to high tension cable (71.1%) on hand (71.1%), upper limbs (24.4%) in autumn (46.8%). They underwent simple dressing (71.1%) and skin graft (24.4%). They showed high morbidity rate (40.0%); loss of consciousness (13.3%), nerve injuries (11.1%), neuropathy (8.9%), amputations (2.2%), and mortality rate (2.2%). Conclusions: The cook should wear apron over the boots during work. The lighter or smoking should be strictly prohibited during work with flammable liquids or bomb powders. Don't directly apply hotpack to skin for a long time. Use insulating glove during electric work. Keep to the basic can prevent severe injury and proper education is important.

A Study on the Performance Improvement for a Natural Gas Engine under Lean Burn & WOT Condition (전부하시 희박영역에서의 천연가스엔진 성능향상에 관한 연구)

  • 김창업;김창기;김승수;방효선;한정옥;조양수
    • Transactions of the Korean Society of Automotive Engineers
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    • v.4 no.6
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    • pp.11-17
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    • 1996
  • Many researches on natural gas engines, with lean mixtures are being conducted for the purpose of preservation of global environment. Lean combustion is one of the most promising method for increasing engine efficiency and reducing the emission from SI engines. Due to the possibility of partial burn and misfire, however, under lean burn operation, stable flame kernel formation and fast burn rate, by use of swirl or tumble flow, are needed to guarantee a successful subsequent combustion. Experimental data were obtained on a 4-stroke, natural gas fueled SI engine to investigate the effect of compression ratio, swirl and spark plug electrode rotation on efficiency and emission under lean burn condition. Experimental results have displayed that higher compression ratio, presence of swirl vane and favorable direction of electrode gap brougth about the improvements in engine efficiency and its operational stability.

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Optimal Burn-In under Warranty

  • Kim, Kui-Nam J.;Park, Chi-Yeon;Hong, Chan-Geui
    • Proceedings of the Safety Management and Science Conference
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    • 1999.11a
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    • pp.147-155
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    • 1999
  • This paper discusses an optimal burn-in procedure to minimize total costs based on the assumption that the failure rate pattern follows a bimodal mixed Weibull distribution. The procedure will consider warranty period as a factor of the total expected burn-in cost. A cost model is formulated to find the optimal burn-in time that minimizes the expected burn-in cost. Conditional reliability for warranty period will be discussed. An illustrative example is included to show how to use the cost model in practice.

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