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REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
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Korean Journal of Agricultural Science
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Journal DOI :
CNU Journal of Agricultural Science
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Volume & Issues
Volume 37, Issue 3 - Dec 2010
Volume 37, Issue 2 - Sep 2010
Volume 37, Issue 1 - Jun 2010
Selecting the target year
Phylogenetic Analysis, Morphology and Pathogenicity of Penicillium spp. associated with Blue Mold of Apple in Korea
Sang, Hyun-Kyu ; Choi, Young-Phil ; Yu, Seung-Hun ;
Korean Journal of Agricultural Science, volume 37, issue 3, 2010, Pages 341~350
Blue mold is the most important postharvest disease of apples in Korea. Apple fruits with blue mold symptoms were collected from storages in different locations in Korea and were investigated for their association with Penicillium species. A total of sixty five isolates of Penicillium were sampled from the collected apples. Based on DNA sequence analysis of
-tublin gene and ITS and lsu rDNA (ID region) and morphological characteristics, they were identified as P. crustosum, P. expansum, P. italicum, P. solitum and P. sp.. P. sp. which is closely related to P. hirsutum is a new species, not reported before. P. expansum (35%) was predominant species followed by P. crustosum. The phylogenetic tree inferred from combined
-tublin and ID region sequence showed good correlation with species that are defined by morphological characteristics. In pathogenicity test, apples were wound-inoculated with conidial suspension and incubated at
. The most severe and destructive species was P. expansum. The species caused a decayed area 42-50mm in diameter after 8-10days. Decayed area caused by P. crustosum and P. sp. was 26-32mm and 20-26mm, respectively. This is the first record of P. crustosum, P. italicum and P. sp. from apple in Korea.
Major Characters of the Developed Sweet Sorghum Lines Induced by Mutagene, Gamma-ray
Bok, Tae-Gyu ; Lee, Moon-Sub ; Shin, Won-Sik ; Ryu, Ji-Hong ; Lee, Hee-Bong ;
Korean Journal of Agricultural Science, volume 37, issue 3, 2010, Pages 351~354
This study was carried out to develop a new sweet sorghum for biomass by using mutagen, gamma-ray. Seeds treated were gained from National Genetic Resource Center, RDA, and these seeds were irradiated with gamma-ray (400Gy) at KAERI. CNUS-M113 and CNUS-M134 among 169 collected accessions were evaluated a promising line for biomass due to increasing of fresh and dry weight. In addition, this line was high in stem height, number of tiller and fresh weight per plant than check, Hwang-gum chal sorghum. Accordingly, this line demanded for leading variety the production test and cultivation adaptability in future years.
Effect of Preharvest Treatment of
and Alkaline-Reduced Water on the Quality of Oyster Mushroom during Storage
Choi, Yun-Soo ; Lee, Kyoung-Min ; Seo, Geon-Sik ; Kim, Min-Kyung ; Hwang, Yong-Soo ;
Korean Journal of Agricultural Science, volume 37, issue 3, 2010, Pages 355~360
This experiment was focused to determine the effect of preharvest treatment of alkaine-reduced water (ARW) and
on the storage of oyster mushroom. ARW was prepared through electrolysis of water with
(0.1%) as salts and
(0.1%) was dissolved in deionized water. Mushrooms were harvested after two sprays of each solutions and quality factors including firmness and browning was determined during storage. The severity of browning was more greater when stored 20 days. Unlike
, ARW containing 139 ug/L calcium was positive on maintaining freshness in terms of delay of firmness loss and respiration drop, keeping soluble carbohydrate content such as trehalose, and inhibiting the occurrence of browning. Browning, however, seemed to be more influenced by the developmental stage of mushroom at harvest. Even no significant difference was found, the level of
-glucan was low in ARW treatment compared to that of control. Further research including application and preparation methods of ARW is required to clarify the potential of ARW on keeping freshness of oyster mushroom through inhibiting tissue browning.
Insecticidal Effects of the Control Released Etofenprox Against Cotton Aphid
Chae, Si-Ra ; Hwang, Chae-Eun ; Seo, Mi-Ja ; Yu, Yong-Man ; Youn, Young-Nam ;
Korean Journal of Agricultural Science, volume 37, issue 3, 2010, Pages 361~365
For the development of more effective insecticides for aphids, including the cotton aphid, Aphis gossypii Glover, control released insecticides were developed and tested as new type of formulation for the cotton aphid. Etofenprox is a target-of-control-released formulation that is toxic to insects with piercing-sucking type mouths including aphids and hoppers. The insecticidal effect of etofenprox is distinguished among others; however, continuance period of the effect of insecticide is shorter than other insecticides. In addition, the control effect of control released etofenprox on the cotton aphid was examined. The results show that control released etofenprox induced no control effects to the cotton aphid within 5 days of treatment. The cotton aphid's population was increased, and their reproduction rate was also high. However, control effect was shown to have very low levels 7 days after treatment, and it increased to higher effect. It is supposed that it is possible to control the cotton aphid using the type of control released etofenprox with a kitosan carrier. It is necessary to develop a more effective carrier type to release more of the insecticidal ingredient on the leaf after spraying.
Molecular Cloning and Characterization of cDNA Encoding Farnesyl Diphosphate Synthase in Garlic (Allium sativum)
Pham, Anh Tuan ; Park, Nam-Il ; Kim, Haeng-Hoon ; Park, Sang-Un ;
Korean Journal of Agricultural Science, volume 37, issue 3, 2010, Pages 367~371
Farnesyl diphosphate synthase (FPS) catalyzes the biosynthesis of farnesyl diphosphate, a precursor for many important terpenoid products. A cDNA encoding FPS was first isolated from Allium sativum (AsFPS) using rapid amplification of cDNA ends (RACE) PCR. The sequence of AsFPS contains an open reading frame encoding a protein of 341 amino acids with a predicted molecular mass of 39.61 kDa. Alignment of AsFPS deduced amino acid revealed high identities with other plants ranging from 79% to 85% and showed 2-high conserved aspartate-rich motifs known to be important for FPS activity. Furthermore, AsFPS expression was stronger in the green organs such as bulbils, scapes, leaves, stems, but weaker in bulbs and roots than on-green organs of A. sativum.
Variation of Essential Oil Content and Its Composition during Callus Subculture of Peppermint (Mentha piperita)
Park, Jung-Suk ; Park, Woo-Tae ; Kim, Haeng-Hoon ; Park, Sang-Un ;
Korean Journal of Agricultural Science, volume 37, issue 3, 2010, Pages 373~376
Peppermint (Mentha piperita L.) belongs to a member of the mint family (Lamiaceae) and is widely used in food, cosmetics and medicines. This study was carried to investigate the variation of essential oil content and its composition during callus subculture of M. piperita. For callus induction from the leaf explant of peppermint, the basal medium was supplemented with various concentrations of 2, 4-D. The best callus induction rate (93%) of M. piperita. was obtained in MS medium containing 2 mg/l 2, 4-D. The induced peppermint callus maintained on Lin-Staba medium were studied during a period of 20th subcultures for the stability of essential oil production. Growth rates of peppermint callus increased during prolonged subculture. However, there was a progressive decrease of essential oil content and unstability of monoterpene productions when callus cultures were serially subcultured.
Isolation and Characterization of the Auxin producing Plant Growth Promoting Rhizobacterium from Soil in a Ginseng Field
Bak, Hae-Sung ; Jung, Young-Pil ; Yoon, Min-Ho ;
Korean Journal of Agricultural Science, volume 37, issue 3, 2010, Pages 377~382
An auxin-producing bacterium (AMT-54) was isolated from ginseng cultivating soil of Geumsan area. The isolate AMT-54 was confirmed to produce indole-3-acetic acid (IAA) which is one of auxin hormone by TLC analysis. When the concentration of IAA was assessed by performing HPLC quantitative analysis, the maximal 457ppm of IAA was detected from the culture filtrate after culturing in R2A broth containing 0.1% tryptophan for 24h at
. The molecular weight of the main peak obtained by LC-mass analysis was correspondent well to 175, that of IAA. The strain AMT-54 was identified as a novel species belongs to Klebsiella mobilis by a chemotaxanomic and phylogenetic analysis. To investigate the growth promoting effect of crop, when the culture broth of K. mobilis AMT-54 was infected onto seed pot of mung bean, the adventitious root induction and root growth of mung bean were 3.3times higher than control.
A Study on Utilization of Mixed Wild Flowers as a Silage Materials
Oh, Hyun-Min ; Lee, In-Duk ; Shin, Yong-Jun ; Kim, Sung-Bok ; Choi, Hyun-Su ; Lee, Bong-Duk ; Lee, Soo-Kee ;
Korean Journal of Agricultural Science, volume 37, issue 3, 2010, Pages 383~386
This experiment was conducted to investigate the quality of wild flowers and mixed wild flower silages. Silage materials employed ochardgrass and mixed wild flower (orchardgrass, white clover, Achillea sibirica Ledeb., Coreopsistinctoria Nutt., Rudbeckiabicolor Nutt., Centaureacyanus L.). Six kilograms of silage materials cut from each treatment were divided into 3 containers, packed by vacuum, and fermented for 40 days. The orchardgrass silage showed significantly higher contents of crude protein than that of mixed wild flower silage. But the neutral detergent fiber and acid detergent fiber contents of orchardgrass silage were significantly lower than those of mixed wild flower silage. pH and butyric acid of orchardgrass silage were significantly lower than those of mixed wild flower silage, and significantly higher in lactic acid contents. It appears that water soluble carbohydrates needs to be supplemented, being grounded on the results above, into wild flower materials both with high fiber materials and with low substances which need lactic acid fermentation.
Fermentation Properties of Amylase Activity and Added Rice Yogurt of Enterococcus faecium KHM-11 Isolated from Korean Human Milk
Bae, Hyoung-Churl ; Lee, Jo-Yoon ; Renchinkhand, Gereltuya ; Nam, Myoung-Soo ;
Korean Journal of Agricultural Science, volume 37, issue 3, 2010, Pages 387~392
This studies were carried out to assess fermentation properties of amylase activity and added rice yogurt of Enterococcus faecium KHM-11 isolated from Korean human milk. The amylase activity of Enterococcus faecium KHM-11 was above 23 units. Characterization of carbohydrate fermentation of Enterococcus faecium KHM-11 has D-ribose, D-lactose, L-arabinose and starch. Titratable acidity and viable count of lactic acid bacteria of 4% rice yogurt was higher compared to the 0%. Therefore we were discussed Enterococcus faecium KHM-11 is suitable microorganism for fermented milk added rice powder. Hydrolysates of sugars of fermented milk with 4% rice powder cultured Enterococcus faecium KHM-11 were analyzed by TLC and HPLC. Hydrolysates of lactose and galactose were revealed and hydrolysates of glucose was not revealed in results of TLC and HPLC.
Progesterone and Estrogen Levels in Holstein Blood and Milk Following Artificial Insemination and Embryo Transfer
Han, Rong-Xun ; Kim, Hong-Rye ; Diao, Yun-Fei ; Kim, Young-Hoon ; Woo, Je-Seok ; Jin, Dong-Il ;
Korean Journal of Agricultural Science, volume 37, issue 3, 2010, Pages 393~398
Early pregnancy diagnosis of bovine is an essential component for efficient reproductive plan in farms because long term of non-pregnancy results in economic losses by failure of offspring production and low milk yield in dairy cattle. The major steroid hormones related with reproduction are known to be progesterone and estrogen in bovine pregnancy. To evaluate detection level of hormones in milk, plasma and milk progestrone and estrogen of Holstein cows was analyzed during artificial insemination (AI) and embryo transfer (ET). Progesterone concentration at 21 days postestrus was significantly different in plasma and milk between pregnant and non-pregnant cows. Estrogen concentration at estrus was higher in pregnant recipients than that in non-pregnant recipients. To analyze correlation between hormone levels and conception rates in Holstein, the conception and return rates were checked following AI, and the returned cows were on the track of pregnancy after consecutive AI. Pregnant cows following first AI were considered as high conception group while pregnant cows following third AI were rated as low conception group. Proportion of high and low conception groups in this study was 78.2% and 9.1%, respectively. Hormone analysis indicated that high conception group had higher estrogen level during estrus than low conception group (
). Progesterone level was not different between high and low conception groups during estrus but increased significantly after 21 days postestrus (21 day:
, 35 day:
). In conclusion, the pattern of progesterone and estrogen secretion in Holstein milk samples could be a good candidate for early pregnancy detection and selection of recipients during ET.
Identification of SNPs in Highly Variable Lysozyme Gene in Korean Native Chicken Populations
Hoque, M.R. ; Kang, B.S. ; Lim, H.K. ; Choi, K.D. ; Lee, J.H. ;
Korean Journal of Agricultural Science, volume 37, issue 3, 2010, Pages 399~404
Single nucleotide polymorphisms (SNPs) in chicken lysozyme (LYZ) gene were investigated in this study. The identification of SNPs in both exon and intron in LYZ gene has led to understanding of evolution for the domestic chicken populations. A total of 24 samples from two Korean native commercial chicken populations (CCPs) were used for the initial identification of SNPs by mixing three DNA samples for sequencing experiments. By comparing with red jungle fowl (RJF), two commercial chicken populations have 18 common polymorphisms. Between two commercial chicken populations, 15 polymorphisms were identified. Of the 33 polymorphisms identified, two indels (21 and 4 bp) were found. Whereas, only one polymorphism in exon 2 at the bp position 1426 was a non-synonymous substitution (p.Ala49Val), indicating the amino acid changes. The identified non-synonymous substitution (p.Ala49Val) is located close to the catalytic sites of the enzyme, which might affect its activity. In our investigation, the polymorphisms in LYZ gene can provide broad ideas for the variation of Korean native chicken populations from the ancestor of chicken breeds as well as the some biological functions of the LYZ gene.
Changes in Kimchi Quality as Affected by the Addition of Sasa borealis Makino Extract
Yook, Hong-Sun ; Jo, Ji-Eun ; Kim, Kyung-Hee ; Hwang, Yong-Soo ;
Korean Journal of Agricultural Science, volume 37, issue 3, 2010, Pages 405~412
This study was focused on finding the potential of hot water extract of bamboo shoot (Sasa borealis Makino) on the fermentation of Kimchi made with Chinese cabbage. The properties of Kimchi were examined up to 28 days of storage. The pH and acidity decreased regardless of treatments and showed no significant difference between treatments. There was a decreasing tendency of both total and reducing sugars in kimchi but the addition of bamboo extract did not affect the soluble sugar levels. Interestingly, bamboo extracts affected the lactic acid fermentation and ripening, resulting in the increase of lactic acid in bamboo extract treatment. Number of total bacterial cell of additive group is higher than control one, probably due to the stimulative effect of bamboo extract on bacterial growth. Level of lactic acid bacteria was also higher in the additive group, thus, it is considered that bamboo extract appeared to enhance the proliferation of lactic acid bacteria. The acceptability of treated Kimchi was higher in general. And results of intensity evaluation in color and texture were higher as well by addition of bamboo extract.
South Dakota Soils: Their Genesis, Classification, and Management
Malo, Douglas D. ; Ryu, Jin-Hee ; Kim, Si-Joo ; Chung, Doug-Young ;
Korean Journal of Agricultural Science, volume 37, issue 3, 2010, Pages 413~433
South Dakota is an important agricultural state in the United States with annual cash receipts from agricultural products exceeding $9 billion dollars. This production is possible because of large areas of productive soils. This publication describes the general characteristics and qualities of the major soil groups recognized in South Dakota. The soil forming factors are briefly described, soil classification is introduced, and the genesis of typical Udalf and Ustoll soils are discussed. Soil management issues impacting the use of SD soils are considered. Long-term (>70 yrs) cultivation has significantly reduced surface soil organic carbon levels (>30% reduction) when compared to non-cultivated soil. Soil test phosphorus levels significantly increased in cultivated fields due to commercial P fertilization. The major long-term production problems for SD soils are conservation of soil moisture, organic matter and nitrogen losses, fertility management, and wind and water erosion control.
Management Strategies to Conserve Soil and Water Qualities in the Sloping Uplands in Korea
Yang, Jae-E. ; Ryu, Jin-Hee ; Kim, Si-Joo ; Chung, Doug-Young ;
Korean Journal of Agricultural Science, volume 37, issue 3, 2010, Pages 435~449
Soils in the sloping uplands in Korea are subject to intensive land use with high input of agrochemicals and are vulnerable to soil erosion. Development of the environmentally sound land management strategy is essential for a sustainable production system in the sloping upland. This report addresses the status of upland agriculture and the best management practices for the uplands toward the sustainable agriculture. More than 60% of Korean lands are forest and only 21% are cultivating paddy and upland. Uplands are about 7% of the total lands and about 62% of the uplands are in the slopes higher than 7%. Due to the site-specificity of the upland, many managerial and environmental problems are occurring, such as severe erosion, shallow surface soils with rocky fragments, and loadings of non-point source (NPS) contaminants into the watershed. Based on the field trials, most of the sloping uplands were classified as Suitability Class III-V and the major limiting factor was slope and rock fragments. Due to this, soils were over-applied with N fertilizer, even though N rate was the recommendation. This resulted in decreases in yield, degradation of soil quality and increases in N loading to the leachate. Various case studies drew management practices toward sustainable production systems. The suggested BMP on the managerial, vegetative, and structural options were to practice buffer strips along the edges of fields and streams, winter cover crop, contour and mulching farming, detention weir, diversion drains, grassed waterway, and slope arrangement. With these options, conservation effects such as reductions in raindrop impact, flow velocity, runoff and sediment loss, and rill and gully erosion were observed. The proper management practice is a key element of the conservation of the soil and water in the sloping upland.
Control of E. coli in Cabbage during Producing Coleslaw by Vinegar for HACCP
Ryu, Dong-Kul ; Ko, Jae-Min ; Park, Su-Hyoung ; An, Gil-Hwan ;
Korean Journal of Agricultural Science, volume 37, issue 3, 2010, Pages 451~455
Cabbage, the main material of coleslaw was not safely washed because it is uneven and tightly layered. In this study, vinegar was used to control the number of E. coli in cabbage for coleslaw production. When cabbage was soaked in 10% acetic acid, The number of bacteria was reduced by
was survived after 5min and
after 30min. After soaking, 15-20% (w/w of cabbage) of 10% acetic acid was remained in chopped cabbage. Spraying 10% acetic acid up to 3% of cabbage weight decreased the number of bacteria by 1/1000 after 60min. Spraying 3% (v/w of cabbage) of vinegar containing 10% acidity decreased the bacteria by 2/3 after 20min but no further decrease was observed. This result indicated that vinegar can be used only in the case that contamination is low.
Properties and Manufacturing of Low Melting Alloy Impregnated Wood Composites for using Domestic Thinned Logs of Juglans mandshurica
Park, Kye-Shin ; Lee, Hwa-Hyoung ;
Korean Journal of Agricultural Science, volume 37, issue 3, 2010, Pages 457~464
The low melting alloy impregnated wood composites with natural grain of thinned Juglans mandshurica was made and evaluated in this study. And the proper manufacturing conditions was also investigated in this study. The low melting alloy with bismuth(Bi) and tin(Sn) which are harmless to humans, was applied for this novel composites, which showed not only no defects of discoloration, delamination, swelling, and cracking, because of high dimensional stability and low thickness swelling, but also much improved performance such as high bending strength, high hardness, low abrasion, high thermal conductivity as floor materials. This study also suggested the proper impregnating condition, such as 10 minutes of the preliminary vacuum time,
of the heating temperature and 10 minutes of the maintaining pressure time at the pressure of 30kgf/
. The produced composites showed 9 times higher density for small specimen, 6.6 times for actual size sample and great increase in bending strength from 102.05N/
for small size sample and to 205.4N/
for actual size sample, also great increase in hardness from 15.1N/
for small size sample and 64.87N/
for actual size sample. And the composites demonstrated great decrease in abrasion depth and in water absorption.
Wood Properties and Residual Creosote Oil of Disused Railway Wood Ties
Lee, Jong-Shin ; Park, Jong-Young ;
Korean Journal of Agricultural Science, volume 37, issue 3, 2010, Pages 465~469
In order to develop effective recycling technologies of disused railway wood ties, wood properties and residual creosote oil of wood ties were investigated. Among the total 50 wood ties, 32 wood ties were identified as tropical hardwood tree, such as, Keruing (Dipterocarpus spp.), Kempas (Koompassia malaccensis), Kapur (Dryobalanops spp.) Naytoh (Palaquium rostratum), and so on. Disused wood ties showed mostly sound structure without degradation of cell walls by decay fungi. Disused wood ties showed high strengths of bending and compressive parallel to grain because degradation of wood properties was hardly occurred in use under exterior condition. Disused railway wood ties had relatively poor depth of penetration and residual of creosote oil because of refractory wood structures. These results suggest that disused railway wood ties may be useful as recycling wood wastes.
Evaluation of Horizontal Position Accuracy in Forest Road Completion Drawing
Kim, Myeong-Jun ; Kweon, Hyeong-Keun ; Choi, Yeon-Ho ; Yeom, In-Hwan ; Lee, Joon-Woo ;
Korean Journal of Agricultural Science, volume 37, issue 3, 2010, Pages 471~479
Forest roads of 16,424km have been constructed as infrastructure for efficient management of forest. The demand of forest road have been also increased steadily with SOC conception for forest management and wood production. But, accuracy verification by completion drawing of forest road needed aspects extration of geographic information to sound like forest road construction and completion drawing. However, verification for completion drawing has not ascertained. This study carried out the evaluation for position accuracy about constructed forest road in Chungcheongnam-do for evaluating horizontal position accuracy of completion drawing of forest road. In result, first of distance of completion drawing and real route designed completion drawing longer than the real route as Gongju 83m, Seosan 66m, Nonsan 27m and Dangjin 19m, respectively. Second, RMSE by point-correspondence was 11m~14.7m, buffering analysis appeared difference of 18~24m. Finally, index of shape was the similar completion and real route through 6.5~7.4 and data information of forest road corresponds to be perfect. For such reasons, the existing completion drawings have a problem that it cannot use graphic information for drawing digital map according to the regulation, and there is an urgent need for improvement to solve this problem in the process of design and construction.
Evaluation of Supplying Instream Flow by Operation Rule Curve for Heightening Irrigation Reservoir
Lee, Jae-Nam ; Noh, Jae-Kyoung ;
Korean Journal of Agricultural Science, volume 37, issue 3, 2010, Pages 481~490
Baekgog reservoir is located in Jincheon county, Chungbuk province, of which full water levels will be heightened from EL. 100.1 m to EL. 102.1 m, and total storages from 21.75
. The simulation for reservoir inflow was conducted by DAWAST model. The annual average irrigation water was estimated to 33.19
supplied to 2,975 ha and the instream flows could be allocated with 0.14 mm/d from October to April with annual average of 2.52
. The operation rule curve was drawn using inflow, irrigation, and instream flow requirements data. The reservoir water storage was simulated on a daily basis in case of both normal and withdrawal limit operation. In case of normal operation, the annual average irrigation water supply increased from 31.95
, the instream water supply from 2.40
, the water storages from 15.74
, and the water supply reliability from 77.3 % to 81.6 %. In case of operation with withdrawal limit, the amount of instream water supply was 2.52
from reservoir regardless of the condition while the water storage increased from 16.77
. The irrigation water supply capacity was appropriate for the case of normal operation with 2 m heightened condition. The present instream water supply capacity was 35,000
/y) while 42,000
/y) in 2 m heightened condition in case of withdrawal limit operation.
Consolidation Characteristics at the Constant Rate of Strain(CRS) Test
Lee, Dal-Won ; Kim, Si-Jung ;
Korean Journal of Agricultural Science, volume 37, issue 3, 2010, Pages 491~499
This study was carried out to investigate the consolidation characteristics of the remolded clay by the oedometer and the constant rate of strain(CRS) consolidation tests. As the rate of strain increases, the settlement rapidly decreased. As the ratio of the sand in the specimen increases, its effect on the rate of strain to the settlement was reduced. As the effective stress increased, the void ratio decreased, while the rate of strain increased, it did not show a clear variation. The reduction of the void ratio was shown to be less than the oedometer test. The coefficient of vertical consolidation with effective stress showed very large variation around preconsolidation stress, but the rate of strain did not provide significant effects. The rate of strain with effective stress gradually decreased at all tests and mixed ratio of sand. The rate of strain at the constant rate of strain tests showed smaller than in the oedometer test. The coefficient of consolidation at the constant rate of strain tests showed much more increase than in the oedometer test. The ratio of the vertical coefficient of consolidation by the odometer and the constant rate of strain tests showed a large difference according to various tests method and mixing ratio. Therefore, it is recommended that careful attention should be paid to designing the soft ground improvement.
Improving Compression and Throat Ratios of Combustion Chamber for Reduction of Exhaust Emissions for a Swirl Chamber Type Diesel Engine
Lee, Chang-Kyu ; Huh, Yun-Kun ; Seo, Sin-Won ;
Korean Journal of Agricultural Science, volume 37, issue 3, 2010, Pages 501~508
A swirl chamber type diesel engine attachable to 18 kW agricultural tractors was improved to reduce exhaust emissions. Compression ratio and throat area ratio of the combustion chamber were varied to determine optimum combustion conditions. Tests were composed of full load and 8-mode emission tests. Compression ratio was fixed as 21, but the swirl chamber volume was increased by 3.8%. Output power, torque, specific fuel consumption, exhaust gas temperature, and smoke level were not considerably different for compression ratios of 21.5 (reference condition) and 21 (test condition), while NOx, HC, CO and PM levels for the compression ratio of 21 were decreased by 11%, 46%, 28%, 11%, respectively, from those for the compression ratio of 21.5. The tests were also conducted with a compression ratio of 22 and 4.3% increased chamber volume. Output power, torque, exhaust gas temperature and smoke level were greater, while specific fuel consumption was less for the compression ratio of 22 than those for the compression ratio of 21.5. Increase of compression ratio decreased HC and CO levels by 24%, 39%, but increased NOx and PM levels by 24%, 39%. Based on these results, a compression ratio of 21 was selected as an optimum value. Then, full load tests with the selected compression ratio of 21 were carried out for different throat ratios of 1.0%, 1.1%, 1.2%. Output power and torque were greatest and smoke was lowest when throat area ratio was 1.1%, which satisfied the target values of specific fuel consumption (less than 272 g/
) and exhaust gas temperature (less than
). Therefore, a throat area ratio of 1.1% was selected as an optimum value.
An Analysis on Technical Efficiency of Apiculture Farming in Korea
Yeo, Min-Su ; Hong, Seung-Jee ;
Korean Journal of Agricultural Science, volume 37, issue 3, 2010, Pages 509~514
The purpose of this study is to analyze the technical efficiency and its determinants for Korean Apiculture farming by using from door to door and e-mail inquiry data. The analysis was implemented through the Cobb-Douglas stochastic frontier production function (SFPF) model including the technical inefficiency effect model for cross-sectional data. To measure the SFPF model, honey production was used for a dependent variable, and for input variables labor cost, preventive cost, material cost, feeding cost, depreciation cost were used. Farmer's age, farmer's career, farming scale, full-time or half-time firm and movement or fixed firm variables were used to measure the inefficiency effect model. The average technical efficiency on apiculture farming in Korea is estimated to be 0.8112. It means that there were technical inefficiency of about 18.88% in Korea apiculture farming. In this study there are some suggestions which could increase the technical efficiency of Korean apiculture farming.
Development of 'Chestnut Cultivation Management Model' Using Benchmarking - Development of 'Chestnut Management Standard Diagnostic Table' That is Able to Apply Chungcheongnam-do -
Ji, Dong-Hyun ; Kim, Yeon-Tae ; Kang, Kil-Nam ; Oh, Do-Kyo ; Noh, Hee-Kyoung ; Kim, Se-Bin ; Kwark, Kyoung-Ho ;
Korean Journal of Agricultural Science, volume 37, issue 3, 2010, Pages 515~522
The purpose of this research was to construct an efficient management system in developing and supplying a 'management standard diagnostic table' for the improvement of chestnut cultivation farmhouse. 'Chestnut management standard diagnostic table' were based from the actual condition of chestnut management in Chungcheongnam-do, selected 'appraisal factor item and by consulting 'agricultural plant standard diagnostic table' and various kinds of data which had already been developed. This research also consulted the classification systems and degree of importance. The developed 'Chestnut management diagnostic table' consisted of 3 first classified items, 19 second classified items and 2 product indicator items.
A Study on Residents Needs Survey and Analysis for Rural Village Development Planning - With Villages on Surrounding Area of Daecheong Dam -
Kim, Dae-Sik ; Kwon, Yong-Dae ; Kim, Jae-Hong ;
Korean Journal of Agricultural Science, volume 37, issue 3, 2010, Pages 523~534
This paper aims to develop a revitalized strategy for Daecheongdong district located on surrounding area of Daecheong dam, which general development projects are restricted by the acts of Green-belt area and Water supply protection zone. The study area consists of 13 villages in Donggu, Daejeon city. This study performed not only survey of amenity and human resources in the whole study area, but also development of new strategy integrating
industries for agriculture with potential. In the sample survey to 11% of village people, the new strategy was accepted positively with 88% of Understanding and 65% of Agreement in answer. The composition plans of farming association and total brand in the study area were agreed by 30% of residents with strong opinion. Representative groups of people living in Donggu, outside of the study area, have also positive opinion of 86% for Purchasing of agricultural products, 89% of Experience tourism, and 61% of Corporation for the study area, which the answering rate was 11% among 326 people. Finally, this study also investigated the corresponding Acts on performing of the new projects extracted in this study.
A Fundamental Study on Survey and Diagnostic of Residents Health for Development of Villages' Health Indices
Lee, Wang-Lok ; Lee, Young-Ran ; Whang, Jung-Min ; Kim, Dae-Sik ;
Korean Journal of Agricultural Science, volume 37, issue 3, 2010, Pages 535~542
The purpose of this study was to survey and diagnostic the self-related health cognition, stress, culture life and health-related fitness for residents of rural area. For this study, Total 126 people answered by a written questionnaire and took part in health-related fitness test for old adults in rural area. According to the normal distribution, the indexes were divided into five grades(very poor 5, poor 4, average 3, good 2, very good 1). The self-related health cognition(SF-36) was third grades. The index was as same as average old adults in rural area. The old adults stress level was third grades. The degrees of stress were as same as average old adults in rural area. The participation in the culture life was fourth grades. The health-related fitness test were third-fifth grades. The results of this experiment could be functioned as a very important fundamental source in order to establish satisfying health system, social welfare for the old people in rural area. Taken together, it seemed that self-related health cognition, stress level, participation in the culture life and health-related fitness have to be considered and improved. The indexes should be further investigated and some practical method should be developed for the olded people in rural area.
Interactions of Phospholipid Liposomes and Bovine Lactoferrin
Kim, Mi-Young ; Kang, Shin-Won ; Park, Jang-Su ; Nam, Myoung-Soo ;
Korean Journal of Agricultural Science, volume 37, issue 3, 2010, Pages 543~545
Apo, holo, native-type of lactoferrin showed a similar pattern of circular dichroism(CD) spectra. Lactoferrin appeared to interact more easily with negatively charged liposome than neutral liposome. Holo-type of lactoferrin showed the highest degree of leakage, whereas apo-type of lactoferrin showed the lowest level of leakage. Holo-type lactoferrin could more easily interact with phospholipid liposomes than apo-type lactoferrin, when used as an artificial membrane.