• Title/Summary/Keyword: System control

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Factors Related with Job Satisfaction in Workers - Through the Application of NIOSH Job Stress Model - (직장인의 직무만족도 관련요인 분석 - NIOSH의 직무스트레스 모형을 적용하여 -)

  • Kim, Soon-Lae;Lee, Bok-Im;Lee, Jong-Eun;Rhee, Kyung-Yong;Jung, Hye-Sun
    • Research in Community and Public Health Nursing
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    • v.14 no.2
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    • pp.190-199
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    • 2003
  • This study was conducted to determine the factors affecting job satisfaction in workers by using the Job Stress Model proposed by the National Institute for Occupational Safety and Health (NIOSH). Data were collected from December 1 to December 30, 1999. The subjects were 2,133 workers employed at 155 work sites, who were examined using NIOSH Job Stress questionnaire translated by the Korea Occupational Safety ${\pounds}|$ Health Academy and Occupational Safety ${\pounds}|$ Health Research Institute. SAS/PC program was used for statistical analysis using descriptive analysis. Pearson's correlation coefficient, ANOVA, and Stepwise multiple regression analysis. The results of this study were as follows. 1. According to general characteristics of the subjects, job satisfaction was high in those with less number of children. 2. By work condition, job satisfaction was higher in those who were working in a permanent job position, were working with regular time basis than with shift basis, were working in regular shift hours than in changing shift hours, were working for a short period, and were working less hours and overtime works per week. 3. In terms of physical work environment, job satisfaction was significantly related to 10 physical environmental factors. In other words, job satisfaction was high in workers who were working in an environment with no noise, bright light, temperature adjusted to an appropriate level during summer and winter, humidity adjusted to an appropriate level. well ventilation, clean air, no exposure to hazardous substance during work hour, overall pleasant work environment and not crowded work space. 4. By work-related factors, job satisfaction was high in those with less ambiguity about future job and role, high job control/autonomy, and less workload. On the other hand, job satisfaction was low in those with little utilization of competencies, and much role conflict at work and workload. 5. As for the relationships between job satisfaction and the non-work related factors, job satisfaction was high in workers who were volunteering at different organizations or active in religious activities for 5-10 hours per week. 6. In the relationships between job satisfaction and buffering factors, significantly positive correlations were found between job satisfaction and factors such as support by direct superior, support by peers, and support by spouse, friend and family. 7. There were nine factors that affected job satisfaction in the workers: age, number of children, work hours per week, noise, temperature at the work site during summer, uncomfortable physical environment, role ambiguity, role conflict, ambiguity in job future, work load, no utilization of competencies and social support from direct supervisor. These nine factors accounted for 26% of the total variance in the multiple regression analysis. In conclusion. the following are proposed based on the results of this study. 1. The most important physical environmental factors affecting job satisfaction in workers were noise, role ambiguity, and work load, suggesting a need to develop strategies or programs to manage these factors at work sites. 2. A support system that could promote job satisfaction is needed by emphasizing the roles of occupational health nurses who may be stationed at work sites and manage the factors that could generate job stress. 3. Job satisfaction is one of the three acute responses to stress proposed in NIOSH job stress model (job satisfaction. physical discomfort and industrial accidents). Therefore, further studies need to be conducted on the other two issues.

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Production of Medium-chain Fatty Acids in Brassica napus by Biotechnology (유채에서의 중쇄지방산 생산)

  • Roh, Kyung-Hee;Lee, Ki-Jong;Park, Jong-Sug;Kim, Hyun-Uk;Lee, Kyeong-Ryeol;Kim, Jong-Bum
    • Journal of Applied Biological Chemistry
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    • v.53 no.2
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    • pp.65-70
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    • 2010
  • Medium-chain fatty acids (MCFA) are composed of 8-12 carbon atoms, and are found in coconut, cuphea, and palm kernel oil. MCFA were introduced into clinical nutrition in the 1950s for dietary treatment of malabsorption syndromes because of their rapid absorption and solubility. Recently, MCFA have been applied to Gastrointestinal Permeation Enhancement Technology (GIPET), which is one of the most important parts in drug delivery system in therapeutics. Therefore, to accumulate the MCFA in seed oil of rapeseed, much effort has been conducted by classical or molecular breeding. Laurate can be successfully accumulated up to 60 mol% in the seed oil of rapeseed by the expression of bay thioesterase (Uc FatB1) alone or crossed with a line over-expressing the coconut lysophosphatidic acid acyltransferase (LPAAT) under the control of a napin seed-storage protein promoter. Also, caprylate and caprate were obtained 7 mol% and 29 mol%, respectively, from plants over-expressing of the medium-chain specific thioesterase (Ch FatB2) alone or together with the chain-length-specific condensing enzyme (Ch KASIV). Despite the success of some research in utilizing parallel classical and molecular breeding to produce MCFA, commercially available seed oils have for the most part, not been realized. Recent research in the field of developing MCFA-enriched transgenic plants has established that there is no single rate-limiting step in the production of the target fatty acids. The purpose of this article is to review some of the recent progress in understanding the mechanism and regulation of MCFA production in seed oil of rapeseed.

On the manufacturing of WPC (Wood Plastic Composites) with Heat-Catalyst Polymerization (I) - On the characteristics of composites made from monomer Methyl MethacryIate and several commercial woods in Korea (가열(加熱)·촉매중합법(觸媒重合法)에 의한 목재(木材)·고분자복합체(高分子複合體) 제조(製造)(I) - MMA에 의한 한국산(韓國産) 주요목재(主要木材)의 복합체특성(複合體特性))

  • Cho, Nam-Seok;Jo, Jae-Myeong;Ahn, Won-Yong
    • Journal of the Korean Wood Science and Technology
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    • v.2 no.3
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    • pp.3-16
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    • 1974
  • One of the disadvantages of. wood and wood products is their hydroscopicity or dimensional instability. This is responsible for the loss of green volume of lumber as seasoning degrade. Dimensional stabilization is needed to substantially reduce seasoning defects and degrades and for increasing the serviceability of wood products. Recently, considerable world-wide attention has been drawn to the so-called Wood-Plastic Composites by irradiation-and heat-catalyst-polymerization methods and many research and developmental works have been reported. Wood-Plastic Composites are the new products having the superior mechanical and physical properties and the combinated characteristics of wood and plastic. The purpose of this experiment was to obtain the basic data for the improvement of wooden materials by manufacturing WPC. The species examined were Mulpurae-Namoo (Fraxinus, rhynchophylla), Sea-Namoo (Carpinus laxiflora), Cheungcheung-Namoo (Cornus controversa), Gorosae-Namoo (Acermono), Karae-Namoo(Juglans mandshurica) and Sanbud-Namoo (Prunus sargentii), used as blocks of type A ($3{\times}3{\times}40cm$) and type B ($5{\times}5{\times}60cm$), and were conditioned to about 10~11% moisture content before impregnation in materials humidity control room. Methyl methacrylate (MMA) as monomer and benzoyl peroxide (BPO) as initiator are used. The monomer containing BPO was impregnated into wood pieces in the vacuum system. After impregnation, the treated samples were polymerized with heat-catalyst methods. The immersed weights of monomer in woods are directly proportionated to the impregnation times. Monomer impregnation properties of Cheungcheung-Namoo, Mulpurae-Namoo and Seo-Namoo are relatively good, but in Karae-Namoo, it is very difficult to impregnate the monomer MMA. Fig. 3 shows the linear relation between polymer retentions in wood and polymerization times; that is, the polymer loadings are increasing with polymerization times. Furthermore species, moisture content, specific gravity and anatomical or conductible structure of wood, bulking solvents and monomers etc have effects on both of impregnation of monomer and polymer retention. Physical properties of treated materials are shown in table 3. Increasing rates of specific gravity are ranged 3 to 24% and volume swelling 3 to 10%. ASE is 20 to 46%, AE 14 to 50% and RWA 18 to 40%. Especially, the ASE in relation to absorption of liquid water increases approximately with increase of polymer content, although the bulking effect of the polymerization of monomer may also be influential. WPCs from Mulpurae-Namoo and Cheungcheung-Namoo have high dimensional stability, while its of Karae-Namoo and Seo-Namoo are-very low. Table 4 shows the mechanical properties of WPCs from 6 species. With its specific gravity and polymer loading increase, all mechanical properties are on the increase. Increasing rate of bending strength is 10 to 40%, compression strength 25 to 70%, ;impact bending absorbed energy 4 to 74% and tensile strength 18 to 56%. Mulpurae-Namoo and Cheungcheung-Namoo with high polymer content have considerable high increasing rate of strengths. But incase of Karae-Namoo with inferior monomer impregnation it is very low. Polymer retention in cell wall is 0.32 to 0.70%. Most of the polymer is accumulated in cell lumen. Effective. of polymer retention is 58.59% for Mulpurae-Namoo, 26.27% for Seo-Namoo, 47.98% for Cheungcheung-Namoo, 25.64% for Korosae-Namoo, 9.96% for Karae-Namoo and 25.84% for Sanbud-Namoo.

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The effects of polishing technique and brushing on the surface roughness of acrylic resin (연마 방법과 칫솔질이 아크릴릭 레진의 표면 거칠기에 미치는 영향)

  • Lee, Ju-Ri;Jeong, Cheol-Ho;Choi, Jung-Han;Hwang, Jae-Woong;Lee, Dong-Hwan
    • The Journal of Korean Academy of Prosthodontics
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    • v.48 no.4
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    • pp.287-293
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    • 2010
  • Purpose: This study evaluated the effect of polishing techniques on surface roughness of polymethyl methacrylate (PMMA), as well as the influence of light-cured surface glaze and subsequent brushing on surface roughness. Materials and methods: A total of 60 PMMA specimens ($10{\times}10{\times}5\;mm$) were made and then divided into 6 groups of 10 each according to the polymerization methods (under pressure or atmosphere) and the surface polishing methods (mechanical or chemical polishing) including 2 control groups. The mechanical polishing was performed with the carbide denture bur, rubber points and then pumice and lathe wheel. The chemical polishing was performed by applying a light-cured surface glaze ($Plaquit^{(R)}$; Dreve-Dentamid GmbH). Accura $2000^{(R)}$, a non-contact, non-destructive, optical 3-dimensional surface analysis system, was used to measure the surface roughness (Ra) and 3-dimensional images were acquired. The surface roughness was again measured after ultrasonic tooth brushing in order to evaluate the influence of brushing on the surface roughness. The statistical analysis was performed with Mann-Whitney test and t-test using a 95% level of confidence. Results: The chemically polished group showed a statistically lower mean surface roughness in comparison to the mechanically polished group (P = .0045) and the specimens polymerized under the atmospheric pressure presented a more significant difference (P = .0138). After brushing, all of the groups, except the mechanically polished group, presented rougher surfaces and showed no statistically significant differences between groups. Conclusion: Although the surface roughness increased after brushing, the chemical polishing technique presented an improved surface condition in comparison to the mechanical polishing technique.

Beneficial Effects of High-Dose Transamine on Hematologic Aspects in Cardiopulmonary Bypass (체외순환시 혈액학적 상황에 대한 고용량 Transamine의 유익한 효과)

  • 김병훈;최석철;최국렬;최강주;조광현
    • Journal of Chest Surgery
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    • v.31 no.10
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    • pp.964-972
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    • 1998
  • Background: The purpose of this study was to independently evaluate the beneficial effects of a high dose of transamine administrated prior to CPB on the postoperative hematologic aspect and bleeding. Materials and methods: This study included randomly selected groups of 40 adult patients undergoing OHS with CPB. All patients were divided into 2 groups: transamine group (T-group, n=20) and placebo group(P-group, n=20). The T-group received a high-dose of transamine(10 g) before and during CPB. The P-group received normal saline at the same times and served as a control group. Results: The results of comparative studies between the 2 groups in the same hematologic variables were summarized as follows. \circled1 During CPB, the fibrinogen concentrations and platelet counts were significantly lower in the P-group than in the T-group(p<0.01). \circled2 During CPB, production of D-dimer occurred in 18 patients(90%) in the P-group and did not occur in the T-group(0%) (p<0.0001). \circled3 At CPB-off, the % concentration of fibrinogen(70.2$\pm$3.9%) and the % platelet counts(72.4$\pm$4.5%) of the T-group were significantly higher than those(54.5$\pm$3.8%, 64.3$\pm$2.9%) of the P-group(p<0.01). \circled4 Postoperative values of PT(14.0$\pm$0.03 sec.) and aPTT (27.6$\pm$0.1 sec.) of the T-group were significantly lower than those(16.0$\pm$0.02sec., 30.1$\pm$0.1sec.) of the P-group(p<0.05). \circled5 Postoperative bleeding and requirement of whole blood and other blood products were significantly less in the T-group than in the P-group(p <0.05). \circled6 There were no significant hypercoagulability signs such as cerebral em bolism, myocardial infarction, pulmonary embolism, or any other neurological prob lems in either group. Conclusions: We concluded that a high dose of transamine administered prior to CPB prevents the activation of fibri nolytic system and has beneficial effects of reducing the postoperative bleeding t endency without apparent hypercoagulability signs.

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Downregulatory Effect of Extracts from Mistletoe (Viscum album) and Pueraria Root (Pueraria radix) on Cellular NF-κB Activation and heir Antioxidant Activity (겨우살이(Viscum album)와 칡뿌리(Pueraria radix) 추출물의 NF-κB활성 억제 및 항산화 효과)

  • Song, Hee-Sun;Park, Yeon-Hee;Kim, Seung-Kyoon;Moon, Won-Kuk;Kim, Dong-Woo;Moon, Ki-Young
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.33 no.10
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    • pp.1594-1600
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    • 2004
  • Effects of mistletoe (Viscum album) extract and pueraria (Pueraria radix) extract on cellular NF-$textsc{k}$B activity were evaluated in human malignant keratinocytes (SCC-13) to elucidate the possible correlation of NF-$textsc{k}$B with antioxidant activity. The antioxidant activities of these natural extracts were examined in four different evaluation methods, i.e., lipid peroxidation value (POV) evaluation test, I,l-diphenyl-2-picrylhydrazyl radical (DPPH), nitric oxide (NO) scavenging test, and reducing power assay. Pueraria extract (0.5 mg) and mistletoe extract (5 mg) downregulated the cellular NF-$textsc{k}$B activation up to 35% and 10% compared to the control, respectively, although their effects were lower than the known NF-$textsc{k}$B downregulator, vitamin C (8.8 mg, 53%) in a cell-based NF-$textsc{k}$B activity assay system. In the POV test, relative antioxidant activities of mistletoe extract (86%) and pueraria extract (75%) were significantly higher than the known antioxidant, vitamin C (48%) at the same concentration (10 mg) and the degree of activity increased in a dose-dependent manner. Pueraria extract showed more potential radical scavenging activities than those of mistletoe extract evaluated in both DPPH and NO test. Especially, the NO radical scavenging activity of pueraria extract ($SC_{50}$/, 88 $\mu$g) was comparable to that of vitamin C ($SC_{50}$/, 77 $\mu$g). Even pueraria extract possessed a much less reducing power compared to vitamin C, it also revealed higher reducing power than that of mistletoe extract. These results indicate that mistletoe extract and pueraria extract may serve as an useful natural antioxidant agents, and led to suggest the hypothesis that compounds having an antioxidant activity, i.e., radical scavenging activity or reducing power may be correlated with the downregulation of NF-$textsc{k}$B activation in human keratinocytes.

A Passport Recognition and face Verification Using Enhanced fuzzy ART Based RBF Network and PCA Algorithm (개선된 퍼지 ART 기반 RBF 네트워크와 PCA 알고리즘을 이용한 여권 인식 및 얼굴 인증)

  • Kim Kwang-Baek
    • Journal of Intelligence and Information Systems
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    • v.12 no.1
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    • pp.17-31
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    • 2006
  • In this paper, passport recognition and face verification methods which can automatically recognize passport codes and discriminate forgery passports to improve efficiency and systematic control of immigration management are proposed. Adjusting the slant is very important for recognition of characters and face verification since slanted passport images can bring various unwanted effects to the recognition of individual codes and faces. Therefore, after smearing the passport image, the longest extracted string of characters is selected. The angle adjustment can be conducted by using the slant of the straight and horizontal line that connects the center of thickness between left and right parts of the string. Extracting passport codes is done by Sobel operator, horizontal smearing, and 8-neighborhood contour tracking algorithm. The string of codes can be transformed into binary format by applying repeating binary method to the area of the extracted passport code strings. The string codes are restored by applying CDM mask to the binary string area and individual codes are extracted by 8-neighborhood contour tracking algerian. The proposed RBF network is applied to the middle layer of RBF network by using the fuzzy logic connection operator and proposing the enhanced fuzzy ART algorithm that dynamically controls the vigilance parameter. The face is authenticated by measuring the similarity between the feature vector of the facial image from the passport and feature vector of the facial image from the database that is constructed with PCA algorithm. After several tests using a forged passport and the passport with slanted images, the proposed method was proven to be effective in recognizing passport codes and verifying facial images.

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A study of Conjunctival Cellular Changes in Dry Eye Patients by Impression Cytology (Impression cytology를 이용한 건성안의 결막 세포변화에 관한 연구)

  • Kim, Jai-Min;Kho, Eun-Gyung;Chae, Soo-Chul;Kim, Soon-Ae
    • Journal of Korean Ophthalmic Optics Society
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    • v.9 no.2
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    • pp.333-343
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    • 2004
  • Impression cytology refers to application of cellulose acetate filter material to the ocular surface to remove the superficial layers of the conjunctival epithelium. The technique is non-invasive, is easy to perform, causes minimal discomfort to the patient, and can be used to follow changes in the conjunctival ocular surface over time. With this method, the morphology of the conjunctival ocular surface can be studied and the degree of squmaous metaplasia assessed. This study was performed to evaluate the conjunctival surface by impression cytology in dry eye patients. A total of 70 students with no contact lens wearing history were recruited. Subjects were required to fill in a McMonnies dry eye symptom questionnaire. The non-invasive tear thinning time(TIT) test of each subject was measured, followed by Schirmer tear test(STI), tear film break-up time(TBUT) tests and Rose-bengal staining were performed as a baseline. Conjunctival epithelial cells from the inferior bulbar conjunctiva were harvested by the impression cytology technique. The specimens collected were labelled and stained with PAS(Periodic Acid Schift)-haematoxylin. The goblet cells and conjunctival epithelial cells were observed under a light microscope of 400x magnification. The specimens were classified according to the Nelson Grading scale which was based on the degree of squamous metaplasia such as changes of goblet cells density, size/form, N:C(nucleus : cytoplasm) ratio. Dry eye patients were observed morphological changes of the epithelial cells, different nuclear alterations, decrease of the goblet cells density. The degree of cytological changes was related to severity of dry eye conditions. When the epithelial cell morphology was graded according to the system described by Nelson, specimens from the control group revealed 91.43% of the eyes to be grade 0 and 8.57% to be grade 1, whereas of the dry eye patients, 20% were grade 0, 42.86% grade 1, 34.29% grade 2 and 2,86% grade 3. Impression cytology represents a non- or minimally invasive biopsy of the ocular surface epithelium with no side effects or contraindications. It has demonstrated to be a useful diagnostic aid for a wide variety of processes involving the ocular surface. This technique is a safe, simple method and may help increase understanding of various ocular surface alterations in dry eye patients.

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Multicenter clinical study on birth weight and associated anomalies of single umbilical artery (단일 배꼽 동맥 환아의 출생체중과 동반기형에 관한 다기관 연구)

  • Bae, Su-Nam;Lim, Jae-Woo;Ko, Kyong-Og;Jin, Hyun-Seung;Kim, Min-Hee;Lee, Bo-Young;Kim, Chun-Soo;Kim, Eun-Ryoung;Park, Sang-Kee;Lee, Jung-Joo
    • Clinical and Experimental Pediatrics
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    • v.52 no.6
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    • pp.655-660
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    • 2009
  • Purpose : To compare birth weight between infants with a single umbilical artery (SUA) and normal infants, investigate the associated anomalies of infants with SUA and isolated SUA (no abnormality of external appearance on birth, except SUA), and determine the prognosis of infants with isolated SUA. Methods : Live-born infants with SUA (n=59) detected by physical examination from among 15,193 live births in seven university hospitals in Korea between January 1, 2004, to August 1, 2007, were reviewed retrospectively, with 236 normal infants serving as the control group. Results : A statistical difference was observed between the groups in birth weight and in vitro fertilization. The incidence of infants with SUA was 0.37%. Congenital malformations were observed in 21 infants with cardiovascular (n=15, 25.4%), gastrointestinal (n=2, 3.4%), genitourinary (n=9, 15.3%), neuromusculoskeletal (n=6, 10.2%), central nervous system (n=1, 1.7%), chromosomal (n=1, 1.7%), and other (n=3, 5.1%) abnormalities. There were 49 (83.1%) infants with isolated SUA in this study population; among them, the associated congenital malformations were cardiovascular (n=6, 12.2%) and genitourinary (n=6, 12.2%) abnormalities. Two infants with cyanotic heart disease were operated and four infants with acyanotic heart disease showed improvements without any treatment. Six infants with genitourinary abnormalities on renal ultrasound had mild hydronephrosis without further consequences. Conclusion : The incidence of structural abnormalities in the cardiovascular and genitourinary systems is high and the genitourinary anomalies associated with isolated SUA have relatively good prognosis.

Optimizated pH and Mitigated Ammonia Emission in Pig Manure Slurry by Soluble Carbohydrate Supplementation (수용성 탄수화물을 이용한 분뇨슬러리 pH 적정화 및 암모니아 휘산의 저감)

  • Lim, Joung-Soo;Hwang, Ok-Hwa;Lee, Sang Ryong;Cho, Sung-Back;Kwag, Jung-Hoon;Lee, Dong-Hyun;Jung, Min Woong;Han, Deug-Woo
    • Journal of the Korea Organic Resources Recycling Association
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    • v.25 no.1
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    • pp.103-110
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    • 2017
  • In Concentrated Animal Feeding Operations(CAFOs), emission of ammonia from stored manure contributes negatively on the wellness of livestock. In CAFOs facilities, indoor aerial ammonia concentration oftentime surpasses the critical level potentially harmful to livestock's immune system. Understandably, numerous researches to control aerial ammonia have been conducted in countries where CAFOs were practiced for many decades. Some innovative technologies, such as scrubber, bio-filter, and additives emerged, as a result. Among them, microbial additives became popular in Korea, due to an easiness of use and affordability. However, microbial additives still have some weaknesses. Their price is still high enough to discourage farmers who run a small scale farm and their effectiveness are still questioned by many users and researchers. In the present study, we found soluble carbohydrates, such as sugar, glucose, and molasses, when supplemented to pig slurry manure, can mitigate ammonia emission. To be more specific, pig manure slurry(120kg), stored in container(200L), was supplemented with sugar at 0.1%(w/w) and was, subsequently, monitored for pH and aerial ammonia for next 10 days. From this experiment, it was found that the sugar supplementation was effective in mitigating the aerial ammonia concentration (33% in average) when monitored daily. Also, the pH of manure slurry was maintained at relatively low level(8.2) in sugar-supplemented manure slurry while it was elevated to 8.5 in untreated slurry. Conclusively, the obtained data suggest that soluble carbohydrate can mitigate ammonia emission by acidifying manure slurry. Additionally, it can be suggested that soluble carbohydrates, such as sugar, glucose, and molasses, can be reasonable choices for animal farmers who have been looking for an alternative choice to replace expensive microbial additives.