• Korean Journal of Fisheries and Aquatic Sciences
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• v.12 no.4
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• pp.225-234
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• 1979

For the effective utilization of diverse and abundant resource of seaweeds in Korea as a food protein supplment, extraction conditions of water, salt, and alkali soluble proteins were investigated in previous work(Ryu and Lee, 1977: Lee et al., 1977: Lee et al., 1978). The present study as a part of the serial work was thus aimed to find the conditions of isolation and purification of extracted proteins, and to evaluate the nutritional quality of the isolated seaweed proteins in terms of amino acid composition, chemical score, protein score, modified essential amino acid index(MEAAI), and in vitro digestibility presented as pepsin-pancreatin digest residue index (PPDRI). As for the isolation of extracted proteins, TCA treatment was more effective for the proteins from rhodophyceae and Chlorophyceae while the precipitation at isoelectric point was more desirable for Phaeophyceae proteins. In amino acid composition, water soluble protein fraction was superior to the other fractions in Porphyra suborbiculata whereas both water and alkali soluble fractions seemed to bo more benefitial for Enteromorpha linza and Ulva pertusa; the extraction with alcohol-alkali mixed solvent for Undaria pinnatifida and Sargassum fulvellum. Glutamic acid and aspartic acid content was particularly high in all protein fractions examined. The total amino acid content of Porphyra suborbiculata and Enteromorpha linza was almost equivalent to that of dried whole egg although the essential amino acid content was lower. A comparative analysis was made on the inedexes between raw seaweed powder and isolated protein. Chemical score of Porphyra suborbiculata and Ulva pertusa was approximately 35 and 56 in cafes of raw powder and isolated protein respectively while only 10 to 16 for raw powder of Undaria pinnatifida and Sargassum fulvellum and 30 to 35 for their isolated proteins. Protein score of all isolated proteins was in the range of 63 to 73 which indicates that isolated protein would be mere valuable than the fern of raw seaweed powder. Digestibility by means of PPDRI was found to be extremely low in case of raw powder but it could be doubled in case of isolated protein yielding 67 to 70 for Porphyra suborbiculata and Ulva pertusa.

• Journal of Animal Science and Technology
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• v.48 no.3
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• pp.443-452
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• 2006

The four rice(Oryza sativa L.) lines, previously demonstrated to have vigorous herbage production at the vegetative growth stage, were investigated for their growth traits, dry matter yield and feed value using the twice-cutting system that 1st-cut is harvested at panicle formation stage and 2nd-cut at the yellow ripen stage. The twice-cutting system is regarded as an effective method in the production of forage rice by escaping lodging and insect damages caused by the overgrowth and typhoon around the heading stage.The feed value of the twice-cut rice plant of there lines were compared with the control of normal, cutting at the yellow ripen stage. The relative feed value(RFV), the total digestible nutrient(TDN) and the crude protein(CP) content of the twice-cut straw were higher the control in every lines. However, the dry matter yield (DMY), represented by the summed forage production of 1st and 2nd cut-rice plant, were lower the control, and the DMY of straws were increase but grains were decrease for twice-cutting system. In addition, TDN yield showed the similar tendency with DMY.Recently, as one of the breeding aims the researches for improving the digestibility of rice straw have been required. In this regard, twice-cutting system is recognized with the fact that it has the effect which raises the digestibility of the straw. Especially, the 2nd cut of IR73111-B-R-15-3-1 line was similar to the control at the TDN yield of straw, and would be used as a breeding material for product the roughage of good quality.

• The Journal of Korean Society for Radiation Therapy
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• v.18 no.1
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• pp.21-28
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• 2006

Purpose: The purpose of this study is to find a optimal beam spoiler condition on the dose distribution near the surface, when treating a squamous cell carcinoma of the head and neck and a lymphatic region with 10 MV photon beam. The use of a optimal spoiler allows elivering high dose to a superficial tumor volume, while maintaining the skin-sparing effect in the area between the surface to the depth of 0.4 cm. Materials and Methods: The lucite beam spoiler, which were a tissue equivalent, were made and placed between the surface and the photon collimators of linear accelerator. The surface-dose, the dose at the depth of 0.4 cm, and the maximum dose at the dmax were measured with a parallel-plate ionization chamber for $5{\times}5cm\;to\;30{\times}30cm^2$ field sizes using lucite spoilers with different thicknesses at varying skin-to-spoiler separation (SSS). In the same condition, the dose was measured with bolus and compared with beam spoiler. Results: The spoiler increased the surface and build-up dose and shifted the depth of maximum dose toward the surface. With a 10 MV x-ray beam and a optimal beam spoiler when treating a patient, a similer build-up dose with a 6 MV photon beam could be achieved, while maintaining a certain amount of skin spring. But it was provided higher surface dose under SSS of less than 5 cm, the spoiler thickness of more than 1.8 cm or more, and larger field size than $20{\times}20cm^2$ provided higher surface dose like bolus and obliterated the spin-sparing effect. the effects of the beam spoiler on beam profile was reduced with increasing depths. Conclusion: The lucite spoiler allowed using of a 10 MV photon beam for the radiation treatment of head and neck caner by yielding secondary scattered electron on the surface. The dose at superficial depth was increased and the depth of maximum dose was moved to near the skin surface. Spoiling the 10 MV x-ray beam resulted in treatment plans that maintained dose homogeneity without the consequence of increased skin reaction or treat volume underdose for regions near the skin surface. In this, the optimal spoiler thickeness of 1.2 cm and 1.8 cm were found at SSS of 7 cm for $10{\times}10cm^2$ field. The surface doses were measured 60% and 64% respectively. In addition, It showed so optimal that 94% and 94% at the depth of 0.4 cm and dmax respectively.

• Korean Journal of Plant Tissue Culture
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• v.28 no.5
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• pp.289-296
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• 2001

The main objective of this topic is to establish strategies and to plan biotechnology researches which are related to the agricultural improvements especially focusing on the crop breeding in Korea. From 1960's to 1980's government policy had been emphasized to develope high yielding cultivars for the self sufficient supply of the staple food crops. As a result, considerable increase of rice production has been made with accumulating technology and man's powers. Recently genetically modified crops harboring useful characteristics have been developed using biotechnology and released in the developed countries. National research institutes and private companies have been developed biotechnology researches to establish competitive capabilities, however they have not been successfully used in commercialization. Therefore it is necessary to promote the practical. application by connecting molecular technology with conventional breeding. Proposed research projects are; (1) basic researches including plant genome studies, (2) developing new cultivars through gene transformation, (3) screening and producing antioxidants, secondary metabolite substances and edible vaccines. To set a government policy, both domestic and international research trends were reviewed and possibility of success based on the economic view point were discussed. The intellectual property and preservation of environment play a key role to decide the research priority. It is also necessary for us to make one step system for the distribution of research resources such as microorganisms, genes cloned, plant seeds and research informations for promoting research activities.

• Asia pacific journal of information systems
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• v.18 no.4
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• pp.57-81
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• 2008

Knowledge is an essential strategic weapon for sustaining competitive advantage and is the key determinant for organizational growth. When knowledge is shared and disseminated throughout the organization, it increases an organization's value by providing the ability to respond to new and unusual situations. The growing importance of knowledge as a critical resource has forced executives to pay attention to their organizational knowledge. Organizations are increasingly undertaking knowledge management initiatives and making significant investments. Knowledge sourcing is considered as the first important step in effective knowledge management. Most firms continue to make an effort to realize the benefits of knowledge management by using various knowledge sources effectively. Appropriate knowledge sourcing strategies enable organizations to create, acquire, and access knowledge in a timely manner by reducing search and transfer costs, which result in better firm performance. In response, the knowledge management literature has devoted substantial attention to the analysis of knowledge sourcing strategies. Many studies have categorized knowledge sourcing strategies into intemal- and external-oriented. Internal-oriented sourcing strategy attempts to increase firm performance by integrating knowledge within the boundary of the firm. On the contrary, external-oriented strategy attempts to bring knowledge in from outside sources via either acquisition or imitation, and then to transfer that knowledge across to the organization. However, the extant literature on knowledge sourcing strategies focuses primarily on large organizations. Although many studies have clearly highlighted major differences between large and small firms and the need to adopt different strategies for different firm sizes, scant attention has been given to analyzing how knowledge sourcing strategies affect firm performance in small firms and what are the differences between small and large firms in the patterns of knowledge sourcing strategies adoption. This study attempts to advance the current literature by examining the impact of knowledge sourcing strategies on small firm performance from a holistic perspective. By drawing on knowledge based theory from organization science and complementarity theory from the economics literature, this paper is motivated by the following questions: (1) what are the adoption patterns of different knowledge sourcing strategies in small firms (i,e., what sourcing strategies should be adopted and which sourcing strategies work well together in small firms)?; and (2) what are the performance implications of these adoption patterns? In order to answer the questions, this study developed three hypotheses. First hypothesis based on knowledge based theory is that internal-oriented knowledge sourcing is positively associated with small firm performance. Second hypothesis developed on the basis of knowledge based theory is that external-oriented knowledge sourcing is positively associated with small firm performance. The third one based on complementarity theory is that pursuing both internal- and external-oriented knowledge sourcing simultaneously is negatively or less positively associated with small firm performance. As a sampling frame, 700 firms were identified from the Annual Corporation Report in Korea. Survey questionnaires were mailed to owners or executives who were most erudite about the firm s knowledge sourcing strategies and performance. A total of 188 companies replied, yielding a response rate of 26.8%. Due to incomplete data, 12 responses were eliminated, leaving 176 responses for the final analysis. Since all independent variables were measured using continuous variables, supermodularity function was used to test the hypotheses based on the cross partial derivative of payoff function. The results indicated no significant impact of internal-oriented sourcing strategies while positive impact of external-oriented sourcing strategy on small firm performance. This intriguing result could be explained on the basis of various resource and capital constraints of small firms. Small firms typically have restricted financial and human resources. They do not have enough assets to always develop knowledge internally. Another possible explanation is competency traps or core rigidities. Building up a knowledge base based on internal knowledge creates core competences, but at the same time, excessive internal focused knowledge exploration leads to behaviors blind to other knowledge. Interestingly, this study found that Internal- and external-oriented knowledge sourcing strategies had a substitutive relationship, which was inconsistent with previous studies that suggested complementary relationship between them. This result might be explained using organizational identification theory. Internal organizational members may perceive external knowledge as a threat, and tend to ignore knowledge from external sources because they prefer to maintain their own knowledge, legitimacy, and homogeneous attitudes. Therefore, integrating knowledge from internal and external sources might not be effective, resulting in failure of improvements of firm performance. Another possible explanation is small firms resource and capital constraints and lack of management expertise and absorptive capacity. Although the integration of different knowledge sources is critical, high levels of knowledge sourcing in many areas are quite expensive and so are often unrealistic for small enterprises. This study provides several implications for research as well as practice. First this study extends the existing knowledge by examining the substitutability (and complementarity) of knowledge sourcing strategies. Most prior studies have tended to investigate the independent effects of these strategies on performance without considering their combined impacts. Furthermore, this study tests complementarity based on the productivity approach that has been considered as a definitive test method for complementarity. Second, this study sheds new light on knowledge management research by identifying the relationship between knowledge sourcing strategies and small firm performance. Most current literature has insisted complementary relationship between knowledge sourcing strategies on the basis of data from large firms. Contrary to the conventional wisdom, this study identifies substitutive relationship between knowledge sourcing strategies using data from small firms. Third, implications for practice highlight that managers of small firms should focus on knowledge sourcing from external-oriented strategies. Moreover, adoption of both sourcing strategies simultaneousiy impedes small firm performance.

• Journal of The Korean Society of Grassland and Forage Science
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• v.35 no.1
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• pp.57-62
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• 2015

"Nokyang" (Hordeum vulgare L.), a new whole-crop silage barley cultivar, was developed by the breeding team at the Department of Rice and Winter Cereal Crop, National Institute of Crop Science, RDA, Korea in 2012. It was derived from combining "Nagyoung" and breeding line "SB77368-B-145". Among the combinations made in 2001, a promising line, "SB01T2017", showed good characteristics in terms of potential forage yield in the yield trial at Iksan from 2007 to 2009. In 2009, the promising line was designated as "Iksan457" and placed in regional yield trials at six locations around Korea for three years from 2010 to 2012, and was released under the name of "Nokyang." It has the growth habit of a group III creeping plant type, with a light-green leaf and common spike. Its average heading and maturing dates were on May 6 and June 4, respectively, which were later than cultivar "Youngyang." "Nokyang" also showed strong winter hardiness, and a resistance to shattering and barley yellow mosaic virus (BaYMV) similar to those of the check cultivar. The best thing among the traits of one is a new good quality with the plant green at the latter growing period. The average forage dry matter (DM) yields in the regional yield trial were about 12.8 and 11.5 MT $ha^{-1}$ in upland and paddy field, respectively, which were higher than those of the check cultivar, by 7% and 2%, respectively. This cultivar would be suitable for an area of the Korean peninsula where the daily minimum temperature in January is above $-8^{\circ}C$.

• Journal of The Korean Society of Grassland and Forage Science
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• v.39 no.4
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• pp.243-249
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• 2019

A barley(Hordeum vulgare L.) cultivar 'Youjin' with hooded spike type having good silage quality was developed at National Institute of Crop Science, RDA in 2016. 'Youjin' showed both high yielding and cold resistance through the preliminary and advanced yield trials(PYT, AYT) from 2012 to 2013. We conducted regional yield trials(RYT) of 'Youjin' in six locations around Korea for three years from 2014 to 2016. It had erect plant type, growth habit of II, the green leaf and hooded awn type. In the paddy field its heading date was April 24 and the maturing date was May 25. Plant height was 99 cm and the number of spikes per ㎡ was 696. It has high rate of leaf blades, resistance to BaYMV(Barley Yellow Mosiac Virus) and good winter hardiness. The average dry matter of Youjin was about 17.2 MT ha^-1 in the field. And feed quality of 'Youjin' was 10.6% of crude protein content, 24.8% of ADF(Acid Detergent Fiber), 43.5 % of NDF(Neutral Detergent Fiber), 69.1% of TDN(Total Digestible Nutrients). And also 'Youjin' had grade I of silage quality.

• Journal of Mushroom
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• v.17 no.4
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• pp.205-210
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• 2019

This study was conducted to elucidate the optimal nitrogen content for each variety of oyster mushroom (Pleurotus ostreatus) by investigating the change in the characteristics of fruiting body according to the nitrogen content of the sawdust media, and to use the results as the basic data for cultivation of high quality oyster mushroom. The nitrogen content was adjusted to 1.3%, 1.6%, 1.8% and 2.3%, and at each condition, mycelial growth was observed, which showed that the nitrogen content did not affect the rate of mycelial growth and density substantially. In the investigation of the characteristics of fruiting body, at the 1.8% nitrogen content, Chunchu No.2 showed the pileus diameter of 27 mm, and the stipe diameter and length of 11 mm and 61 mm, respectively, and the measurement of its color values revealed that the brightness of the pileus and the stipe was 31 and 80, respectively, offering the best commercial value, and yielding 25 valid stipes, which was the largest number. Likewise, at the 1.8% nitrogen content, Heuktari also showed the excellent growth characteristics including the pileus diameter of 29 mm and the stipe diameter and length of 10 mm and 68 mm, respectively, and the superb color values of the brightness of 37 at the pileus and 78 at the stipe. Moreover, the number of valid stipes was also found to be the highest with 19. In terms of morphological characteristics such as the pileus diameter and color, Soltari also produced the best mushrooms at the 1.8% nitrogen content and the number of valid stipes was high with 22. In summary, irrespective of varieties of oyster mushroom, high quality products could be cultivated at the nitrogen content of 1.8%.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.36 no.4
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• pp.345-350
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• 1991

Rough rice samples of Chucheongbyeo, Bongkwangbyeo and Hwaseongbyeo were collected by the National Agricultural Products Inspection Office. Drying methods of rough rice were sun drying and forced ventilation drying by an oven dryer and temperature of the oven dryer was set to 43, 60, 70, or 8$0^{\circ}C$. Moisture content of samples was reduced from ca. 20% to 15% at the end of drying, and additionally to 12.5 % for the drying at 8$0^{\circ}C$. Characteristics related to rice grain quality, milling recovery, ratio of broken and cracked rices, percentage of germination, and sensory scores of the cooked rices were evaluated. Yielding percentage of brown rice and polished rice remarkably decreased by drying at 8$0^{\circ}C$. Percentages of cracked rice and broken rice were within the criterion of the second grade government brown rice (20%) only in the sun dried and the rices dried at 43$^{\circ}C$, on the basis of damaged rice, opaque kernel rice and colored rice. Broken rice percentage of the polished rice was within the criterion for the standard of government rice (5%) in the sun dried and the rices dried at 43$^{\circ}C$. Germination percentage of rough rice was higher than 80% in sun drying and drying at 43$^{\circ}C$, but remarkably decreased by drying rice at 6$0^{\circ}C$ and over. Sensory palatability of the cooked rice decreased with increase in drying temperature. The present governmental method of judging rough rice on the basis of moisture content and appearance of the rough rice appears to be improved to include the ratio of broken and cracked rices.

• Journal of The Korean Society of Grassland and Forage Science
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• v.22 no.3
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• pp.213-220
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• 2002

The growth characteristics, forage yields and nutritive values of heading and headless types of sorghum $\times$ sudangrass(Sorghum bicolar L.) hybrids were examined to evaluate the adaptability of new cultivars at Suwon and Chunahn for two years from 2000 to 2001 in a randomized complete block design with three replications. Eleven cultivars of heading type and 4 cultivars of headless type were used in this study. The dry matter(DM) yield of AG 2501 was highest in the heading type cultivars, and PAC F8350 in the headless type cultivars, respectively. The DM yields of heading types were slightly higher than those of headless types but there were not significantly different. Early growth and regrowth characteristics of heading type was highest in AG 2501 and GW 9110G, respectively. GW 9110G and DMD were early heading types, and AG 2501 and GW 9161F were middle heading types. AG 2501 was longest and GW 9161F was shortest in plant height. Cultivars with long leaf length were appeared to be larger fur leaf width and stem diameter. Brix content was highest in DMD as 9.7%, and disease and insect resistances were not significantly different among the heading types. Early growth of headless type cultivar, PAC F8350 was slightly lower than that of Jumbo but stronger in regrowth, wider in leaf width and stem diameter, and stronger in lodging. Comparisons of growth characters between heading and headless types of cultivars were not easy in general but between them, brix contents of heading types ranging from 6.7 to 7.9% were greatly higher than those of headless types ranging from 3.6 to 3.9%. Nutritive values such as crude protein, ADF, NDF and digestibility of headless type cultivars were higher than those of heading types. In conclusion, of heading type cultivars, GW 9110G, AG 2501, DMD and GW 9161F, and of headless type cultivars, Jumbo and PAC F8350 were recommended as high yielding cultivars with good adaptability in domestic environment.