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A Contemplation on Measures to Advance Logistics Centers (물류센터 선진화를 위한 발전 방안에 대한 소고)

  • Sun, Il-Suck;Lee, Won-Dong
    • Journal of Distribution Science
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    • v.9 no.1
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    • pp.17-27
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    • 2011
  • As the world becomes more globalized, business competition becomes fiercer, while consumers' needs for less expensive quality products are on the increase. Business operations make an effort to secure a competitive edge in costs and services, and the logistics industry, that is, the industry operating the storing and transporting of goods, once thought to be an expense, begins to be considered as the third cash cow, a source of new income. Logistics centers are central to storage, loading and unloading of deliveries, packaging operations, and dispensing goods' information. As hubs for various deliveries, they also serve as a core infrastructure to smoothly coordinate manufacturing and selling, using varied information and operation systems. Logistics centers are increasingly on the rise as centers of business supply activities, growing beyond their previous role of primarily storing goods. They are no longer just facilities; they have become logistics strongholds that encompass various features from demand forecast to the regulation of supply, manufacturing, and sales by realizing SCM, taking into account marketability and the operation of service and products. However, despite these changes in logistics operations, some centers have been unable to shed their past roles as warehouses. For the continuous development of logistics centers, various measures would be needed, including a revision of current supporting policies, formulating effective management plans, and establishing systematic standards for founding, managing, and controlling logistics centers. To this end, the research explored previous studies on the use and effectiveness of logistics centers. From a theoretical perspective, an evaluation of the overall introduction, purposes, and transitions in the use of logistics centers found issues to ponder and suggested measures to promote and further advance logistics centers. First, a fact-finding survey to establish demand forecast and standardization is needed. As logistics newspapers predicted that after 2012 supply would exceed demand, causing rents to fall, the business environment for logistics centers has faltered. However, since there is a shortage of fact-finding surveys regarding actual demand for domestic logistic centers, it is hard to predict what the future holds for this industry. Accordingly, the first priority should be to get to the essence of the current market situation by conducting accurate domestic and international fact-finding surveys. Based on those, management and evaluation indicators should be developed to build the foundation for the consistent advancement of logistics centers. Second, many policies for logistics centers should be revised or developed. Above all, a guideline for fair trade between a shipper and a commercial logistics center should be enacted. Since there are no standards for fair trade between them, rampant unfair trades according to market practices have brought chaos to market orders, and now the logistics industry is confronting its own difficulties. Therefore, unfair trade cases that currently plague logistics centers should be gathered by the industry and fair trade guidelines should be established and implemented. In addition, restrictive employment regulations for foreign workers should be eased, and logistics centers should be charged industry rates for the use of electricity. Third, various measures should be taken to improve the management environment. First, we need to find out how to activate value-added logistics. Because the traditional purpose of logistics centers was storage and loading/unloading of goods, their profitability had a limit, and the need arose to find a new angle to create a value added service. Logistic centers have been perceived as support for a company's storage, manufacturing, and sales needs, not as creators of profits. The center's role in the company's economics has been lowering costs. However, as the logistics' management environment spiraled, along with its storage purpose, developing a new feature of profit creation should be a desirable goal, and to achieve that, value added logistics should be promoted. Logistics centers can also be improved through cost estimation. In the meantime, they have achieved some strides in facility development but have still fallen behind in others, particularly in management functioning. Lax management has been rampant because the industry has not developed a concept of cost estimation. The centers have since made an effort toward unification, standardization, and informatization while realizing cost reductions by establishing systems for effective management, but it has been hard to produce profits. Thus, there is an urgent need to estimate costs by determining a basic cost range for each division of work at logistics centers. This undertaking can be the first step to improving the ineffective aspects of how they operate. Ongoing research and constant efforts have been made to improve the level of effectiveness in the manufacturing industry, but studies on resource management in logistics centers are hardly enough. Thus, a plan to calculate the optimal level of resources necessary to operate a logistics center should be developed and implemented in management behavior, for example, by standardizing the hours of operation. If logistics centers, shippers, related trade groups, academic figures, and other experts could launch a committee to work with the government and maintain an ongoing relationship, the constraint and cooperation among members would help lead to coherent development plans for logistics centers. If the government continues its efforts to provide financial support, nurture professional workers, and maintain safety management, we can anticipate the continuous advancement of logistics centers.

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Identification of Streptomyces scopuliridis KR-001 and Its Herbicidal Characteristics (Streptomyces scopuliridis KR-001의 분리 동정 및 잡초 방제효과)

  • Lee, Boyoung;Kim, Jae Deok;Kim, Young Sook;Ko, Young Kwan;Yon, Gyu Hwan;Kim, Chang-Jin;Koo, Suk Jin;Choi, Jung Sup
    • Weed & Turfgrass Science
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    • v.2 no.1
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    • pp.38-46
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    • 2013
  • With increasing environmental issues from synthetic chemical herbicides, microbe-originated herbicides could be a fascinating alternative in current agriculture. We isolated Streptomyces strains that produced herbicidal active metabolite(s) against a grass weed Digitaria sanguinalis. According to the result from 16S rDNA sequence comparison with the close strains, the best isolate (Code name MS-80673) was identified as Streptomyces scopuliridis KR-001. The closest type strain was Streptomyces scopuliridis RB72 which was previously reported as a bacteriocin producer. The optimal culture condition of S. scopuliridis KR-001 was $28^{\circ}C$, pH 7.0 and culture period 4 to7 days. Both of soil and foliar application of the crude culture broth concentrate was effective on several troublesome or noxious weed species such as a Sciyos angulatus in a greenhouse and field condition. Phytotoxic symptoms of the culture broth concentrate of S. scopuliridis KR-001 by foliar application were wilting and burndown of leaves, and stems followed by discoloration and finally plant death. In crops such as rice, wheat, barley, hot pepper and tomato, growth inhibition was observed. These results suggest that the new S. scopuliridis KR-001 strain producing herbicidal metabolites may be a new bio-herbicide candidate and/or may provide a new lead molecule for a more efficient herbicide.

Study on Soluble Concentrate Formulation and Quality Control Techniques of a Microbial Insecticide "Bt-Plus" (미생물살충제 "비티플러스" 액상 제형화 및 품질 분석 기술에 관한 연구)

  • Eom, Seonghyeon;Park, Hyeonji;Kim, Kyusoon;Hong, Youkyeong;Park, Jiyeong;Choi, Bongki;Kim, Joonsung;Kim, Kunwoo;Kang, Moonsoo;Yang, Kyunghyung;Kim, Yonggyun
    • Korean journal of applied entomology
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    • v.52 no.2
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    • pp.115-123
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    • 2013
  • A microbial insecticide "Bt-Plus" has been developed to enhance an insecticidal efficacy of an entomopathogenic bacterium, Bacillus thuringiensis (Bt). However, its wettable powder formulation is not preferred by farmers and industry producers due to relatively high cost. This study aimed to develop a soluble concentrate formulation of Bt-Plus. To this end, an optimal mixture ratio of two bacterial culture broths was determined to be 5:4 (v/v) of Bt and Xenorhabdus nematophila (Xn) along with 10% ethanol preservative. In addition, Bt broth was concentrated by 10 times to apply the mixture at 1,000 times fold dilution. The resulting liquid formulation was sprayed on cabbage crop field infested by late instar larvae of the diamondback moth, Plutella xylostella. The field assay showed about 77% control efficacy at 7 days after treatment, which was comparable to those of current commercial biopesticides targeting P. xylostella. For storage test in both low and room temperatures, the liquid formation showed a relatively stable control efficacy at least for a month. To develop a quality control technique to exhibit a stable control efficacy of Bt-Plus, Bt spore density ($5{\times}10^{11}$ spores/mL) and eight active component concentrations of Xn bacterial metabolites in the formulation products have been proposed in this study.

Antioxidant Activities of Phenolic Compounds from Medicinal Plants (Hibiscus esculentus, Cirsium japonicum, Zizania latifolia and Kalopanax pictus) (약용식물(오크라, 엉컹퀴, 엄나무, 줄풀) 유래 페놀성 물질의 항산화 활성)

  • Choi, Jin-Young;Jo, Min-Kyeong;Goo, Young-Mi;Kim, Hyun-Kyung;Shin, Jin-Won;Kim, Dong-Yeong;Kim, Hye-Jin;Lee, Eun-Ho;Kim, Na-Hyun;Cho, Young-Je
    • Current Research on Agriculture and Life Sciences
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    • v.33 no.2
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    • pp.57-63
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    • 2015
  • In this study, the antioxidant activity of water and ethanol extracts from Hibiscus esculentus, Cirsium japonicum, Zizania latifolia and Kalopanax pictus for functional food source were examined. The optimal conditions for phenolic compounds extraction from medicinal plants were at 50% ethanol with Hibiscus esculentus and Cirsium japonicum var. ussuriense, at 40% ethanol with Kalopanax pictus and at 60% ethanol with Zizania latifolia. The total phenolic contents from the extracts of medical plants were determined to be 2.72~34.15 mg/g in the water extracts and 2.83~34.23 mg/g in the ethanol extracts. The electron-donating abilities (EDA) of the water and ethanol extracts were both above 74% at the low concentration of $50{\mu}g/mL$. The ABTS radical-cation decolorization was above 88% at $100{\mu}g/mL$ concentration in all the extracts of various medicinal plants. The antioxidant protection factor (PF) in the water and ethanol extracts of the Cirsium japonicum var. ussuriense extracts was $1.73{\pm}0.02PF$ and $1.76{\pm}0.01PF$ at $50{\mu}g/mL$ concentration respectively, and was higher than those of the other medicinal-plant extracts. The TBARs inhibition rates of all the medicinal-plant extracts, were above 80% at the $50{\mu}g/mL$ concentration except Hibiscus esculentus. These results confirmed that the various oriental medicinal plants (Hibiscus esculentus, Cirsium japonicum var. ussuriense, Kalopanax pictus and Zizania latifolia) that were included in this study are useful anti-oxidant and functional-food resources.

Changes in the Hyperspectral Characteristics of Wheat Plants According to N Top-dressing Rates at Various Growth Stages (밀에서 질소 시비 조건에 따른 생육 단계별 초분광 특성 변화)

  • Jung, Jae Gyeong;Lee, Yeong Hun;Choi, Jae Eun;Song, Gi Eun;Ko, Jong Han;Lee, Kyung Do;Shim, Sang In
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.65 no.4
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    • pp.377-385
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    • 2020
  • Recently, wheat consumption has been increasing in Korea, requiring increased production. Nitrogen fertilization is a critical determinant in crop yield; therefore, it is necessary to optimize the nitrogen fertilization regime with current trends that emphasize the minimum impact of nitrogen fertilizer on the environment. In this study, both nondestructive spectral analysis using a hyperspectral camera and growth analysis were performed to determine the optimal N top-dressing rates after heading. The nitrogen application regimes consisted of three conditions according to the secondary top-dressing rate: N4:3:0 (0 kg 10 a-1), N4:3:3 (2.73 kg 10 a-1), and N4:3:6 (5.46 kg 10 a-1). Subsequently, growth and physiological investigations were performed at the jointing, heading, and ripening stages of wheat, and spectral investigations were conducted. On April 29, as the nitrogen fertilization rate was increased to N4:3:3 and N4:3:6, plant height and grain yield increased by 4% and 8%, and 8% and 52%, respectively, compared to those under N4:3:0. Leaf area index and SPAD value also increased by 13% and 24%, and 32% and 43%, respectively. The R (red), G (green), and B (blue) of leaf color were lowered by 15, 11, and 4 in N4:3:3 and 44, 34, and 18 in N4:3:6, respectively, as compared to the control. Grain yield was the highest at high top-dressing (N4:3:6), however, there was no difference between no top-dressing (N4:3:0) and intermediat top-dressing (N4:3:3). The reflectance analyzed using a hyperspectral camera showed a difference in the near-infrared (NIR) region on March 19, and on April 29, there was a difference both in the visible light region greater than 550 nm and the NIR region. Vegetation indices differed according to fertilization regime, except for the greenness index (GI). The results of this study showed that not only growth and physiological analysis but also spectral indices can be used to optimize the nitrogen top-dressing rate.

Characteristics of Pelletized Swine Manure Compost (돈분뇨 퇴비의 펠렛가공 효과)

  • Jeong, K.H.;Kim, J.H.;Choi, D.Y.;Park, C.H.;Kwag, J.H.;Yoo, Y.H.;Han, M.S.;Jeong, M.S.;Won, H.H.;Yoon, T.Y.
    • Journal of Animal Environmental Science
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    • v.14 no.3
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    • pp.201-210
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    • 2008
  • Farmers directly spread the livestock manure compost on their arable land as an organic fertilizer. However, there are some difficult problems to solve. first, we are unsure of whether the livestock manure compost can meet the nutritional demand of plant. Second, application of the current powered livestock manure compost to crop land is very difficult work due to heavy weight of compost and its powdered shape. For this reason, this study was carried out to develope high quality pelletized livestock manure compost. In pelletizing process with composted manure, the optimal water content for pelletizing was around 30$\sim$40%. When rice bran was mixed with 5% as a bonding agent on volume basis, the pelletizing effect was remarkably improved. On a dry matter basis, the contents of N and P of manure compost were 1.31%, and 0.58%, respectively. After pelletizing, the contents of compost pelleted were 1.37% and 0.54%, respectively. The same parameters of pelletized compost made by screw type Instrument were 1.37% and 0.53%, respectively. The other hand, N and P content of pelletized compost made by pellet mill type instrument were 1.06% and 0.18%, respectively.

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Optimization of Solvent Extraction Process on the Functional Components from Portulaca oleracea Using a Response Surface Methodology (쇠비름의 유용성분 환류추출공정의 최적화)

  • Jo, In-Hee;Kim, Tae-Yeon;Ma, Ji-Bock;Lee, Jin-Ju;Lee, Hyo-Jeong;Choi, Yong-Hee
    • Current Research on Agriculture and Life Sciences
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    • v.29
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    • pp.83-89
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    • 2011
  • Various functional and useful components in Portulaca oleracea were extracted with ethanol and the optimum solvent conditions were set by monitoring of response surface methodology(RSM). A central composite design for optimization was applied to investigate the effects of the three independent variables of extraction temperature, ethanol concentration, and extraction time, on dependent variables including total phenolics, electron-donating ability, brown clolor and total flavonoids of Portulaca oleracea. The content of total phenol was essentially unaffected by extraction time or extraction temperature, but it was highly influenced by ethanol concentration. The maximum total phenol content was 31.70mg/mL obtained at 45.84% of ethanol concentration, $79.66^{\circ}C$, and after 2.67hr of extraction. Electron-donating ability (EDA) was affected by ethanol concentration and the maximum EDA was 74.67mg/mL at 52.95% ethanol concentration, $52.33^{\circ}C$ and 4.84hr of extration time. The browning color was rarely affected by extraction time but, it was highly influenced by ethanol concentration and extraction temperature. The maximum extent of browning color was obtained at 97.75% of ethanol concentraion, $65.88^{\circ}C$ and 2.93hr of extraction time. The content of total flavonoid was significantly influenced by extraction time, and the maximum total flavonoid level was 58.28mg/mL obtained at 96.62% ethanol concentration, $61.87^{\circ}C$ after 3.70hr of extraction. As a result, The optimal conditions for effective extraction were predicted as follows, 70.3% of ethanol concentration, $62.1^{\circ}C$ of extraction temperature and 3.3hr of extraction time.

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The Evaluation of Potential Invasive Species in the Gangneungnamdae Stream in Korea using a Fish Invasiveness Screening Kit (FISK (Fish Invasiveness Screening Kit)를 이용한 강릉남대천의 잠재적 침습 이입종 평가)

  • Kim, Jeong Eun;Lee, Hwang Goo
    • Korean Journal of Environmental Biology
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    • v.36 no.1
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    • pp.73-81
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    • 2018
  • This study was conducted to understand the current status of the translocated species using a precede study and a model to evaluate the potential invasiveness that could adversely affect the aquatic ecosystem in the Gangneungnamdae Stream. A total of 12 translocated species were investigated and identified from 9 sites in a precede study, and steadily increased since 1982. For the study, which utilized research based on the total FISK (Fish Invasivenss Screening Kit) scores, all of the non-native fishes in Gangneungnamdae Stream were classified into two groups: namely as a high and a medium risk of becoming invasive. It was determined that there were two species (Zacco platypus and Pseudorasbora parva) that were determined to have posed the highest risk. The study determined that the mean scores were shown to have ranged from $3.06({\pm}0.16)-3.42({\pm}0.13)$. Consequently, the habitat analysis showed that the determined QHEI (Qualitative Habitat Evaluation Index) values in the stream averaged 146 (88-171), indicating that an optimal habitat condition did exist in that locale. It can be inferred that compared to land use in the surrounding watersheds, the QHEI values and frequency of translocated species showed the lower the altitude of stream, the QHEI values were decreased and in case of land use pattern, a noted decreased forest and grassland area, and gradually increased urbanized area was seen to exist in the region. The correlation between the fish assemblage, QHEI, land use pattern of surrounding watershed and number of translocated species was identified and analyzed when the stream altitude decreased, and the number of species was increased (r= - 0.782, p=0.0127), the number of species was decreased (r= - 0.737, p=0.0234), and finally when the QHEI values were decreased, it was noted that the urbanized area was increased (r=0.292, p=0.446). In the case of the number of translocated species, when the number of translocated species was increased, the associated urbanized area was increased.

Isolation and Fusion of Pea Mesophyll Protoplast (완두(Pisum sativum L.) 엽육세포(葉肉細胞) 원형질체(原形質體)의 분리(分離) 및 융합(融合))

  • Kwon, Yil Chan;Kim, Dal Ung;Kim, In Seob
    • Current Research on Agriculture and Life Sciences
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    • v.6
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    • pp.13-18
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    • 1988
  • This experiment was conducted to identify the enzyme treatment time, calcium ion effect, enzyme concentration and leaf position for protoplast isolation. It was also performed to determine the adequate molarity on protoplasts, and to investigate the incubation time, pH, PEG concentration and DMSO effect for protoplast fusion. The results obtained were summarized as follows ; The optimal time of incubation in enzyme solution was 4 hours. And the protoplast releasing time was delayed by $CaCl_2{\cdot}2H_2O$ addition to the enzyme solution compared with no added one. The viability had kept up to above 95% until the 4 hours after digestion. The high viability of the protoplast was preserved more than 16 hours by adding $CaCl_2{\cdot}2H_2O$ to digestion solution. The enzyme concentration had no effect on protoplast yield in range from 1% to 5% and the first or second leaf from the top of the plant produced the highest protoplast yield among the leaf position tested. The purity of healthy protoplast was better in 0.4M and 0.5M sucrose than in others, and the percentage of protoplast aggregation was more 20% to 50% in PEG 6,000 compared with 4,000 and PEG 1,500. Even though the percentage of protoplast aggregation was less increased by 3% to 7% than without DMSO, its treatment was effective to induce binucleated protoplasts.

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A Correlation between Axis-Rotation and Corneal Eccentricity in Toric Soft Contact Lens Fitting in With-the-rule Astigmatism (직난시안에서의 토릭소프트렌즈 피팅 시 축 회전과 각막이심률과의 상관관계)

  • Park, Hyung Min;Park, Kyounghee;Kim, So Ra;Park, Mijung
    • Journal of Korean Ophthalmic Optics Society
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    • v.19 no.3
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    • pp.305-313
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    • 2014
  • Purpose: A correlation between the rotating direction and rotation amount according to the eccentricity was analyzed in the present study when fitting the toric soft contact lens. Methods: One hundred fourteen eyes of with-the-rule astigmatism in 20s and 30s were appropriately applied toric soft contact lens by the guideline of manufacturer and fitting evaluations and analyzed the rotating direction and rotation amount when fixating at primary position and 8 different directions of gaze. The speed of reorientation and the correlation between the rotation amount and cornea eccentricity were also analyzed when rotating $45^{\circ}$ each toward the temporal and nasal direction. Results: The cornea eccentricity and rotation amount was shown positive correlation. For the gaze of direction, it was identified that the gaze of directions other than the gaze of direction towards the nasal and temporal had correlation, and among them, the gaze of directions to superior and the superior-temporal showed the tendency of decreasing rotation amount as the cornea eccentricity increased. On the contrary, the gaze of direction towards the inferior, inferior-temporal, superior-nasal, and inferior-nasal showed tendency of increasing rotation amount as the cornea eccentricity increased thus, it was identified that the cornea eccentricity showed different correlation according to the gaze of direction. For the case of re-orientational speed, the speed of lens reorientation in the group having the smallest corneal eccentricity was fastest in both direction but was not significantly different. Conclusions: Considering cornea eccentricity to current method of prescribing toric soft contact lens which is based on total astigmatism, it will be helpful to establish the optimal axis stabilization.