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Determination of Experimental Conditions for Measurement of the Clearance Rate of an Intertidal Bivalve, Glauconome chinensis

  • Lee, Chang-Hoon;Chung, Ee-Yung
    • The Korean Journal of Malacology
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    • v.17 no.2
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    • pp.95-104
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    • 2001
  • To determine optimal conditions for measurement of the clearance rate in feeding experiment of an intertidal bivalve Glauconome chinensis, effects of starvation, extent of mixing at subsampling, and initial prey concentration were assessed. Experiments were conducted separately for each condition with different treatments. Two-way ANOVAs showed that there were significant differences in clearance rates among different starvation periods (p<0.001), extents of mixing (p = 0.005), and prey concentrations (p < 0.001). Starvation for 1 or 2 days gave rise to 2 to 3-fold increase in the clearance rate. After starvation for 5 days, the clearance rate decreased seriously, implying loss of physiological status. It is suggested that animals should be fed during acclimation. The differences of the clearance rates between gentle and vigorous mixings were significant, but the differences were smaller than that among different incubation times. It was found that vigorous mixing is not necessary. The effect of initial prey concentration was great. However, optimal prey concentration could not be determined at any fixed value. Experiments with multiple concentrations of algal prey are recommended. Optimal incubation time for measurement of the clearance rate of G. chinensis was determined to be 2-4 hours.

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Plus-size Women and Appearance Management with a Focus on Clothing -Grounded Theory Based Exploratory Study- (근거이론에 기초한 플러스 사이즈 여성 소비자의 의류를 중심으로 한 외모관리에 관한 탐색적 연구)

  • Yu, Haekyung;Ko, Sunyoung;Kim, Chanju
    • Journal of the Korean Society of Clothing and Textiles
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    • v.37 no.3
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    • pp.306-319
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    • 2013
  • This study explores various issues of appearance management behavior for plus-size women in Korea with a focus on clothing. In-depth interviews and focused group interviews were conducted with 24 plus-size women. The interviews were recorded and the transcripts were analyzed based on grounded theory. Discomfort was the main phenomenon involving the experience of plus-size women related to appearance management. Psychological as well as physiological/physical discomfort, unmet needs (regarding clothing) and inconvenient shopping experiences were frequently mentioned. Causal conditions for discomfort were obesity, social stigma, and an underdeveloped clothing market for plus-size consumers. Interviewees developed strategies to cope with discomfort (suppressing clothing need, loss of interest in clothing, diversion from clothing needs, sole focus on physical comfort, dress-up and increase in shopping channels, and change in shopping patterns) that depended on contextual conditions (such as duration of obesity and attitudes of people) close to the interviewees. The discomfort of interviewees decreased or continued depending on if they became ambivalent about their obese condition, lost weight, or utilized plus-size specialty stores.

Phytotoxic Effect of 5-Aminolevulinic Acid, a Biodegradable Photodynamic Biomaterial, on Rice and Barnyardgrass

  • Chon, Sang-Uk
    • Korean Journal of Environmental Agriculture
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    • v.25 no.3
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    • pp.268-275
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    • 2006
  • ALA (5-aminolevulinic acid) has been proposed as a tetrapyrrole-dependent photodynamic herbicide by the action of the protoporphyrinogen IX oxidase (Protox IX). A study was conducted to determine photodynamic herbicidal effect of ALA on seedling growth of rice (Oryza sativa L.) and barnyard grass (Echinochloa crus-galli Beauv. var. oryzicola Ohwi) under dry and wet conditions. ALA effect on early plant growth of rice and barnyardgrass was greatly concentration dependant, suggesting that it promotes plant growth at very low concentration and inhibits at high concentration. No significant difference in herbicidal activity of biologically and synthetically produced ALAs on plant lengths of test plants was observed ALA exhibited significant photodynamic activity regardless of PSDIP and its duration. Significant shoot growth inhibition by ALA soaking treatment exhibited apparently, indicating that ALA absorbed through root system was translocated into shoot part of plants. ALA reduced plant heights of rice and barnyardgrass seedlings by 6% and 27%, respectively, showing more tolerant to ALA in rice under wet condition. Leaf thickness was reduced markedly by ALA with increasing of ALA concentration, due to mainly membrane destruction and severe loss of turgidity in mesophyll cells, although the epidermal was little affected. It was observed that photodynamic herbicidal activity of ALA applied by pre-and post-emergence application exhibited differently on plant species, and that the activity of ALA against susceptible plants was highly correlated with growing condition.

A Study on Thermo-flow Characteristics Analysis of Electric Water Pump (전동 워터펌프의 열유동 특성 해석에 관한 연구)

  • Kim, Sung-Chul;Song, Hyeong-Geun
    • Transactions of the Korean Society of Automotive Engineers
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    • v.20 no.5
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    • pp.95-101
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    • 2012
  • An electric water pump for engine cooling system has an advantage which particularly in the cold start, the use of the electric water pump saves fuel and leads to a corresponding reduction in emissions. The canned type electric water pump without mechanical sealing elements was selected to meet the requirements for operational reliability and life. However, the electric water pump for internal combustion engine generates much more heat loss than for hybrid electric vehicle since it is operated by the electric power of high current and low voltage. In this study, the fluid flow and thermal characteristics of the canned type electric water pump as an inverter integrated water pump has been investigated under the effects of heat generation. The analysis conditions such as outdoor air temperature of $125^{\circ}C$, water pump speed of 6000 rpm, coolant temperature of $106^{\circ}C$ and coolant flow rate of 120 L/min was used as a standard condition. Therefore, flow fields and temperature distribution inside the water pump were obtained. Also, we checked the feasibility of the canned type for the electric water pump in comparison with the mechanical seal type.

Development of a Low Noisy Type of Air-line Mask (저소음형 송기마스크 개발)

  • Paik, Eun-Gyu;Kim, Bong-Nyun;Kim, Kwang-Jong
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.15 no.3
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    • pp.277-281
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    • 2005
  • Air-line mask is an important personal protective equipment for workers working under hazardous surroundings in which a fixed ventilation system is difficult to be installed. If the air-line mask make loud noise, works wearing the mask may be faced with health problems such as noise induced hearing loss(NIHL). The purpose of this study is to introduce a low noisy technology for workers using air-line mask. A traditional type air-line has been improved to an advanced air-line mask with lesser noise. In the mask, air suppling conduits consists of multi tubes are placed inside of the front of the safety helmet. The noise level reduced from 80dB(A) to less than 80dB(A) when measured by KS A 0701 method at Center for Safety Inspection, Testing and Certification for KOSHA. It is suitable for related regulation[Article 35 of the Industrial Safety and Health Act(Test of Personal Protective Equipment)]. While workers working in noise level of over 90dB(A), they may expose to 82dB(A) or less when they wear the advanced masks. This type masks can be an alternative for works suffering from loud noise generated by traditional air-line masks.

The Economic Burden of Cancers Attributable to Metabolic Syndrome in Korea

  • Kim, Dongwoo;Yoon, Seok-Jun;Gong, Young-Hoon;Kim, Young Ae;Seo, Hye-Young;Yoon, Jihyun;Kim, A-Rim
    • Journal of Preventive Medicine and Public Health
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    • v.48 no.4
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    • pp.180-187
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    • 2015
  • Objectives: Metabolic syndrome is an important etiologic factor in the development of certain types of cancers. The economic cost of the treatment of cancer has been steadily increasing. We therefore estimated the economic burden of cancers attributable to metabolic syndrome in Korea. Methods: We reviewed metabolic syndrome-related cancers and relative risk and then calculated population attributable fractions. We analyzed insurance claims data for metabolic syndrome-related cancers in 2012 in order to estimate the direct costs associated with these cancers, including hospitalization, outpatient visits, transportation costs, and caregivers' costs as well as indirect costs such as loss of productivity due to cancer treatment and premature death. Results: In 2012, 18 070 patients in Korea had cancers attributable to metabolic syndrome. The economic burden was USD 199.8 million and the direct and indirect costs were USD 124.5 million and USD 75.3 million, respectively. Conclusions: We estimated the economic burden of cancers attributable to metabolic syndrome in Korea and the efforts are necessary to reduce this burden.

A Study on Soot Formation of Turbulent Premixed Propane Flames in n Constant-Volume Combustor at High Temperatures and High Pressures (고온ㆍ고압 정적 연소기내 난류 프로판 예혼합 화염의 매연생성에 관한 연구)

  • 배명환
    • Transactions of the Korean Society of Automotive Engineers
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    • v.9 no.4
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    • pp.1-9
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    • 2001
  • The soot yield has been studied by a premixed propane-oxygen-inert gas combustion in a specially designed disk-type constant-volume combustion chamber to investigate the effects of pressure, temperature and turbulence on soot formation. Premixtures are simultaneously ignited by eight spark plugs located on the circumference of chamber at 45 degree intervals in order to observe the soot formation under high pressures. The eight flames converged compress the end gases to a high pressure. The laser schlieren and direct flame photographs for observation field with 10 mm in diameter are taken to examine into the behaviors of flame front and gas flow in laminar and turbulent combustion. The soot volume fraction in the chamber center during the final stage of combustion at the highest pressure is measured by the in situ laser extinction technique and simultaneously the corresponding burnt gas temperature by the two-color pyrometry method. The pressure and temperature during soot formation are changed by varying the initial charge pressure and the volume fraction of inert gas compositions, respectively. It is found that the soot yield increases with dropping temperature and rising pressure at constant equivalence ratio, and that the soot yield of turbulent combustion decreases in comparison with that of laminar combustion because the burnt gas temperature increases with the drop of heat loss.

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Peripheral Arterial Injuries in Pediatric Age Group

  • Ammar, Ahmed AbdulRaouf
    • Journal of Trauma and Injury
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    • v.29 no.2
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    • pp.37-42
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    • 2016
  • Purpose: Arterial injury in children is a challenging problem for its special characteristics. It is rare even during warfare. This review described a personal experience in the management and outcome of acute pediatric arterial injuries of extremities. Methods: Thirty-six children below age of 13 years were studied during period from 2004 through 2014 in Iraq. Results: Male patients were 27 (75%) and female were 9 (25%). Seven to twelve years old was the most affected age group. The incidence of iatrogenic injuries was greater in infants and toddlers while penetrating injuries were the most common in older children. Upper limbs arteries were affected in 17 (47.2%) and lower limb in 19 (52.8%) patients. Hard signs were the commonest mode of presentation (83.3%). Lateral wall tear and complete transection were the most frequent types of arterial injury (36.1% and 27.8% respectively). The most frequent procedures performed were end-to-end anastomosis and lateral arteriorrhaphy. Surgical outcome was good. In 27 cases distal pulsations were regained. Seven cases had impalpable distal pulses but still viable limbs. Limb length discrepancy was detected in one case. One case was complicated with limb loss. No death was recorded. Conclusion: Arterial injuries in children are age related. The proper treatment of arterial injuries in children requires high index of suspicion, early operative intervention and continuous postoperative follow-up throughout years of active growth. Angiogram has a limited role as a diagnostic tool in acute arterial injuries.

Study on Male Chronic Fatigue in Hyungsang Medicine (남자 만성피로의 형상의학적 고찰)

  • Park, Tae-Sook;Lee, Yong-Tae
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.19 no.3
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    • pp.605-611
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    • 2005
  • Chronic fatigue refers to the tiredness which disturbs one's daily activities and lasts more than six months without the sign of improvement by rest or sleep. Male chronic fatigue is included in internal injuries due to overstrain and exhaustion and closely related to river, spleen, stomach and kidney out of five Jang organs. Male chronic fatigue is based on the deficiency of Yang and aggravated by liquor, sex and emotional depression. Chronic fatigue has the following features in Hyungsang ; an inclination for lying: unwillingness to everything; drooping eyes and feeble voice; yellow pale complexion; withered ears; redness on the tip of nose; cheekbone, and lips; blood shot eyes; dryness and loss of hair. Male chronic fatigue usually attacks the persons of horse type and bird type because they are hyperactive compared with what they eat. The following medicines are commonly prescribed for the treatment of male chronic fatigue. Ssangwhatang, Sokunzungtang, and Yanghyulsamultang are commonly prescribed to horse type. Jaumkangwhatang, Chungsimyunzaum, Yookmijiwhangtang to bird type. Palmiwhan, Gozinumja. and Shinkihwan to fish type. Bozungikkitang, Galwhahaesungtang, Samchulgunbitang and Sipjundaebotang to turtle type.

Development of A New Concept Rotary Engine (I) - Concept and theoretical performance analysis - (신개념 로터리 엔진의 개발 (I) - 개념과 이론적 성능 분석 -)

  • 오문근;이규승;박원엽
    • Journal of Biosystems Engineering
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    • v.28 no.1
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    • pp.27-34
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    • 2003
  • Present combustion engines have reached almost at the limit of development due to the fundamental structural problems. This study was carried out to propose a new concept internal combustion engine which has great potential advantages to the conventional engines. Proposed new concept engine is a kind of rotary engine. A rotor is rotating concentrically in a cylinder which is divided into two partitioning valves. and it makes four compartments in the cylinder. The volumes of each of four compartments are changing continuously with the rotor movement, and performs the functions of intake, compression. expansion and exhaust simultaneously. The results of this study can be summarized as follows. 1. Expected theoretical thermal efficiency is 44.9 percent at the condition of 1000rpm and compression ratio of 8.0. which is almost the same as that of the conventional engines. i.e., piston and Wankel rotary engine. 2. The new concept engine has 2. working strokes in every revolution. Therefore. the new concept engine can reduce the specific weight and volume than four-stroke piston engine. 3. The torque variation is very small. therefore minimal noise and vibration are expectable. 4. The new concept engine can reduce mechanical energy loss than piston engine because neither crank mechanism nor eccentrical motion exists.