• Journal of Korea Technology Innovation Society
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• v.11 no.2
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• pp.145-170
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• 2008

The existence of network is indeed the single most important factor that brings about new business phenomena in the new digital economy, especially in the IT industry. Network effect refers to a phenomenon that the increase in size of the network leads to increased network value and user utility. It determines the competitive structure of an industry and the performances of industry competitors (Shapiro and Varian, 1999). The phenomenon of increasing returns and winner-take-all enjoyed by the early winner in the competition can be attributed to the existence of positive feedback which increases the value of network and induces more users into join the network (Arthur, 1996; Shapiro and Varian, 1999; Song and Lee, 2003). This research attempts to shed light on the topic of innovation and competitive strategy of network-based industries. We analyze the case of the Korean mobile communications industry, in which a shift in technological paradigm from 2G to 3G brought new changes to the competitive structure of the industry. The Korean mobile communications industry makes an ideal case for analysis since it is an industry whose value is inherently dependent upon its user network. It is characterized by the typical increasing returns, in which a monopolizing player is enjoying firstmover's network effects. Because of the existence of network in the mobile communications industry, latecomers' disruptive innovations could not outcompete the incumbent's sustaining innovations. The contribution of this research lies in laying a groundwork for future studies by introducing a numerical simulation model to analyze the complexity theory and network effect.

• Applied Biological Chemistry
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• v.11
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• pp.89-93
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• 1969

The strains selected in the previous paper were identified according to the manual of Aspergilli by Thom and Raper, and the preparation of the crude enzymes with the strains were investigated. The fermented fodders were made with wheat bran and chaffs containing 20% wheat bran by the strains, and the feeding experiments concerned was conducted. The results obtained are as follows: 1. The selected strains were identified as below; MC-9 was a similar strain of Aspergillus niger van Tieghem, MC-10 was a similar strain of Aspergillus flavus Link, MC-53 was a similar strain of Aspergillus penicilloides Spegazzini and MC-61 was a similar strain of Aspergillus niger mut Schiemanni n. comb. 2. Percentages of crude enzymes obtained from the dried matters of the wheat bran cultures were MC-9: 2.9%, MC-10: 3.9%, MC-53: 6.4% and MC-61:2.6%. And the cellulase activity of MC-9 was the most active among the crude enzymes as the same as the filtrates of wheat bran cultures. 3. As the results of the feeding experiments, changes of body weights showed no trends to be significant as compared with the control group, and the groups of MC-9 and MC-61 showed the increasing significance with P<0.05 in egg-laying rate.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.12 no.1
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• pp.396-407
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• 1999

Although tinnitus is a common disease, it's reason, pathogenesis and treatment are not examined clearly. As tinnitus is a subjective complaint, it is not easy to evaluate objectively and to compare with another. In this study, we intend to estimate the effect of a variety of oriental medical treatments to tinnitus. We inquired about 30cases of tinnitus patients visited the Kwang-ju Oriental Medical Hospital of Wonkwang University from Apr. 1998 to Sep. 1998. We examined the 30cases in the view of sex, age, occupation, duration, etiologic factors, past history, associating symptoms, quality of tinnitus, and recovery rate after treatments. The results were as follows: 1. In distribution of sex, the ratio of male was $63.3\%$(19cases)and\;female\;was\;36.6\%$(11cases). 2. In distribution of age, the ratio of the 2th decade was $6.6\%(2cases),\;the\;3th\;decade\;was\;20.0\%(6cases),\;the\;4th\;decade\;was\;16.6\%(5cases),\;the\;5th\;decade\;was\;23.3\%(7cases),\;the\;6th\;decade\;was\;30.0\%\;(9cases),and\;the\;7th\;decade\;was\;3.3\%(1case)$. 3. In distribution of occupation, the ratio of employee was $23.3\%$(7cases), house-keeper was $63.3\%(11cases),\;farmer\;was\;16.6\%(5cases),\;teacher\;was\;13.3\%$ (4cases), and student, merchant, soldier was each $3.3\%$(1case). 4. In distribution of duration, the ratio of under 1month was $6.6\%$ (2cases), 1 month -6 months was $20.0\%$(6cases), 6 months- 12months was $30.0\%$(9cases), 12months-36months was $23.3\%$(7cases), and over 36months was $20.0\%$(6cases). 5. In etiologic factor of tinnitus, the ratio of unknown reason was $40.0\%$ (12cases), overwork was $16.6\%$(5cases), emotional stress was $10.0\%$(3cases), noise was $6.6\%$(2cases), cases of laying overwork upon stress was $13.3\%$(4cases), head trauma was $3.3\%$(1case), gun report was $3.3\%$ (1case), and after sickness was $6.6\%$(2cases). 6. 9 cases had experienced such a disease as meniere's disease, tympanitis, labyrinthitis, trauma of tympanum, hypertension, etc. 7. Commonly associated symptoms were dizziness, deafness, uneasiness, headache, ear fullness, fatigue, insomnia, nausea, vomiting, and forgetfulness. 8. Most frequent quality of tinnitus were buzzing, whistling, humming etc. 9. In $76.6\%$(23cases) of tinnitus patients, it was improved, but in $23.3%$(7cases) of them, not improved. Total recovery rate was $42.2\%$.

• Proceedings of the Korea Society of Poultry Science Conference
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• 2003.11a
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• pp.91-92
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• 2003

비태인의 급여(0, 600 ppm)가 사료의 단백질 수준(14, 16 ％)에 따라 산란계의 생산성과 난품질, 혈액성상, 간과 가슴육의 일반성분에 미치는 영향을 구명하기 위하여 83주령 하이라인 산란계 192수를 이용하여 12주간 사양실험을 실시하였다. 기초사료는 에너지 수준이 2,800 kcal/kg, methionine과 lysine, cystine의 수준은 단백질 수준에 비례하도록 하였다. 조사항목으로 산란율과 난중, 사료섭취량, 사료요구율, 계란품질은 4주 간격으로 측정했다. 실험 종료시 복강지방과 혈액중 total protein과 albumin, BUN, triglyceride, total cholesterol, HDL-cholesterol, LDL-cholesterol 함량, 간의 methionine, choline 함량, 간과 가슴육의 수분, 조단백질, 조지방 함량을 측정하였다. 산란율은 단백질 수준에 따라 증가하였으며(P＜0.05) 비태인 급여에 의한 차이는 없었다. 난중은 단백질과 비태인 급여로 증가하였으며(P＜0.05) 산란양은 단백질 수준이 증가할수록 감소하였다(P＜0.05). 비태인 급여로 사료 요구율은 현저하게 개선되었지만(P＜0.05), 계란의 품질은 차이가 없었다. 혈청 total protein은 비태인 급여로 현저히 증가하였으며 특히 단백질 14 ％ 급여구에서 크게 증가하였다(P＜0.05). 복강지방 함량은 단백질 수준과 비태인 급여에 따라 감소하는 경향을 보였다. 가슴육과 간의 조단백질 함량은 사료의 단백질 수준에 따라 증가하였다(P＜0.05). 간의 조지방 함량은 비태인의 급여로 감소하는 경향을 보였다. 간의 methionine 함량은 단백질과 비태인 수준에 따라 증가하는 경향을 보였으며 choline 함량은 비태인의 급여에 의해서만 증가하는 경향을 보였다. 따라서 비태인의 급여는 단백질 수준이 높은 조건에서 산란율을 개선시키고 난중을 증가시키며 사료 요구율을 개선한다.록 산가는 증가하는 것을 볼 수 있다. 홍국주의 전자 공여능에 의한 항산화력은 25.6%, 아질산염 소거능은 27.6%, Total phenolic compound 함량은 12.34mg%, ACE저해작용은 38%의 항산화력을 나타냈다.과 $O_2$와 $CO_2$의 농도에서 평균오차 0.2%로 정밀한 것으로 나타났으며 호흡속도 측정용 챔버의 혼합기체 공급측과 배기측의 가스 농도를 3회 반복 측정한 결과 재현성에서는 0.1%이하의 편차로 나타났다. 개방계 호흡속도 자동 측정 시스템을 이용하여 환경기체조성하에서 토마토의 호흡속도를 측정하는 실측 실험을 수행한 결과 2$0^{\circ}C$에서 12.7~42.1mg$CO_2$/kg.hr였으며 12$^{\circ}C$에서 2.5~8.2mg$CO_2$/kg.hr로 일반적으로 보고되고 있는 토마토 호흡속도와 일치하는 결과를 나타내었다.다.환원당인 sucrose 함량은 계속 증가하였고 fructose, glucose, sorbitol의 함량(추황의 sorbitol을 제외)은 생장이 촉진됨에 따라 증가하다가 다시 점차적으로 감소하였다. 이러한 결과는 총당과 환원당의 측정결과와 일치한 것으로 나타났다. 결론적으로 배의 성장에 따라 산 함량은 감소하였고 당 함량은 증가하였다.luco-pyranoside, quercetin 7-O- -glucopyranoside, acacetin 7-O-$\beta$-D-glucuronide and apigenin-6-C-$\beta$-D-glucopyranosyl-8-C-$\beta$-D-glucopyranoside were first isolated and identified from safflower leaf. Among these flavonoids, luteolin

• Korean Journal of Poultry Science
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• v.30 no.2
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• pp.101-106
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• 2003

In order to study the optimum daily protein allowance for broiler breeders of 24 to 64 weeks of age on a control-fed basis, an experiment was carried out with 400 hens of Arbor Acres strain. Four levels of protein allowances were used to supply 18 to 24g of protein per day in 2g increments. As the age of hens increased, a same stepwise increase and decrease in daily energy allotment was used in all treatments. Same amount of calcium, phosphorus, methionine and lysine were supplied in all treatments and throughout laying period. Hen-day egg production was highest in hens receiving 20g protein per day(p<0.05), but there was no significant difference among those fed daily protein ranging 18 to 22g, and increasing the daily protein allotment up to 24g resulted in a significant decrease(p<0.05). Average egg weight showed a trend to increase as the daily protein allowance increase(p<0.05), but no significant difference was found among the hens fed daily protein 20 to 24g. Feed and ME conversion was superior in hens receiving 20g daily protein(p<0.05). CP conversion was increased as the daily protein allowance increase(p<0.05), but there was no significant difference between hens receiving 18 and 20g daily protein. Feed cost required per egg or per kg egg was lowest in hens fed 20g daily protein. It could be concluded that the optimum daily protein allowance was 20g in all performances.

• Korean Journal of Poultry Science
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• v.30 no.2
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• pp.107-112
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• 2003

This experiment was conducted to study the optimum energy feeding system for broiler breeders peaked in summer season with 400 caged hens of Ross strain. Four of energy supply series which were different in daily energy allotment during laying period were employed for 40 weeks from 24 to 64 weeks of age. All experimental diets were formulated to contain 2,750 kcal ME/kg with adjustments made in total feed allotment to provide the desired energy levels. Total consumption of the feed would provide 20 grams of protein, 4 grams of calcium and 0.35 grams of available phosphorus. There were no significant difference in hen-day egg production and average egg weight among the series of energy supply, but egg production showed a trend to decline as the level of energy allotment increased. Feed, ME and CP conversion and feed cost required per egg or per kg egg were significantly increased as the level of energy allotment increased(p<0.05). It was concluded that the Treatment 1, which supplied 280kcal ME per day at the age of 24 weeks and then increased the energy supply up to 400kcal ME per day at the peak period of 30∼34 weeks of age, was superior in all production parameters.

• Korean Journal of Poultry Science
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• v.20 no.4
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• pp.217-231
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• 1993

Due to the increased awareness on the relationship between high cholesterol intake and cardiovascular disease, the development of low cholesterol eggs and egg products are necessary at the present time. Largely, two approaches are possible to develop low cholesterol eggs. The first approach is the production of low cholesterol eggs by altering feeds of layers, by administering drugs, by genetic selection of strains and breeds, and by management of laying cycle, age and egg size. The second approach is to manufacture low cholesterol eggs technically treated with adsorbant, solvent, enzyme, edible oil and supercritical fluid. Both approaches have their own pros and cons, respectively, as far as the cholesterol removal rates, the easeness of process, and the economic reasons are concerned. The low cholesterol egg production is quite labor-intensive and has relatively low cholesterol removal rate(30∼50％ ) compared to that of chemically treated eggs. On the other hand, the low cholesterol eggs treated with chemicals have a very high cholesterol removal rate (80∼90％) but some of the methods are not completely safe as food processing purposes due to the residual chemicals and the sensory quality is not as good as the low cholesterol eggs without chemical treatment. Therefore, further studies must be conducted to improve the sensory quality of low cholesterol eggs and to eliminate fear about the harmfulness using low cholesterol eggs.

• Journal of Food Hygiene and Safety
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• v.17 no.3
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• pp.129-136
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• 2002

This study was conducted to Provide basic information Promoting egg qualify improvement and hygienic control by grasping of present market egg distribution system and hygienic quality. The eggs of 57 brands collected from the department food stores in Incheon Metropolitan City were examined. Eggs were kept in room temperature in all the market and 70.2% of the brands were marked the expiration date indicating that eggs would be available over 28 days after being laid. Fifty-four % of the market eggs was classified as a special or functional egg. Expiration date and date of laying were common labelling items in all brands. These items were labelled in trade mark sheet or eggs tray. Only 66.6% of the brands had the mark about net quantity of contents. The inspection about the exterior and contents of eggs has results as follows: eggshell contamination of feces and feather-9.5%, abnormal and broken eggshell -3.9%, blood and meat spots in contents -14.7% and watery whites -1.8%. Average of Haugh Unit(HU) was 56.1 and below HU 31 were 18 of 285 eggs(6.3%), in addition, more than one egg detected in 12 brands(21.1%) among 57 brands have inferior quality. Salmonella enteritidis from eggshell and antibodies directed from S. enteritidis in the yolks of eggs available in the market were not detected. Ranges of Total bacterial count (CFU/ml) on eggshell of eggs were < 10~8.2$\times$10$_3$, and isolation ratio of Escherichia coli were 4.7%. Tetracyclines were detected in 1.8% of the eggs(1 of57 brands) by CHARMII. As mentioned above, quality control and improving distribution system were required to facilitate egg consumption and improve public health by complementing labelling items and quality standards.

• The Southeast Asian review
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• v.21 no.1
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• pp.137-184
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• 2011

This article is aimed at understanding the political narratives represented in the National Museum of Indonesia. Starting initially as a colonial museum, the National Museum of Indonesia functioned as a useful tool for the Dutch colonial force to fuel its imaginations of the colonial territory and the people within it. The Dutch used the cultural display to advertize its benevolent colonial rule. All the while, the museum also inevitably reflected orientalism on the people and the culture of the colony. The republic of Indonesia inherited the colonial museum's practices and its display patterns. The business surrounding the museum also played a key role in the newly-born nation-state laying out a future for its redefined territory and people. Thus, what the colonial force imagined for the colonial territory through the study of museum displays was rather directly transferred to the republic without serious consideration of the decolonization process. Four main characteristics have been seen in the museum displays. The first is an emphasis on the glorious Hindu-Buddha history, from which numerous temples, statues, and jewelry have been found. Secondly, the Islamic period, which spanned between the Hindu-Buddha times to the colonial era, has almost completely been eliminated from the display. Third, the colonial era has been depicted as the time of Europe's exportation of scientific tools and adaption of sophisticated living patterns. Fourth, the images of ethnic groups were represented as being stagnant without reflecting any challenges and responses that these groups had faced throughout history. Looking at these display patterns, it can be concluded that all the dynamic internal developments and anti-colonial resistance that took place during the Islamic and Colonial Era have simply not been represented in the museum display. These display patterns do not reflect the real history or culture of the archipelago. Two considerations are thought to have influenced the neglecting of social realities in the display. The first of which is the Dutch's and Republic's apprehension over the possible political upheaval by the Islamic forces. Yet, more fundamentally, cultural displays themselves are distinct from historical education in that the former pays more attention to business ideas with an aim to attract tourists rather than to project objective historical knowledge. Thus, in cultural displays, objects which work to stimulate fantasies and spur curiosity on archipelagic culture tend to be selected and emphasized. In this process, historical objectivity is sometimes considered less vital. Cultural displays are set up to create more appealing narratives for viewers. Therefore, if a narrative loses its luster, it will be replaced by another flashy and newly-resurrected memory. This fact reveals that museums, as transmitters of historical knowledge, have a certain degree of limitation in playing their role.

• The Journal of the Convergence on Culture Technology
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• v.5 no.4
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• pp.367-371
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• 2019

In this study, we proposed the sacrificial anode cathodic protection method as a countermeasure to reduce the corrosion of railway rails under oceanic climatic conditions and proved the anticorrosive effect experimentally. In addition, the proposed sacrificial anode cathodic protection method were tested on site to examine long-term rail corrosion monitoring and field applicability for more than 26 months and to prove the effectiveness of rail corrosion. As a result of monitoring the corrosion state using the cellophane tape method, the appearance of the applied sections with sacrificial anode cathodic protection method was good at the present time about 26 months after the field test laying, and no abnormalities and other abnormalities of the rail welded section and the rail web were found. Hence, in places where no sacrificial anodes were installed, rust progressed rapidly. In addition, the proper spacing of sacrificial anodes was found to form the most stable corrosion coating at 1.0 ~ 1.5m. After about 26 months of monitoring, the installation of sacrificial anodes could help stabilize the overall rail corrosion level, even if the spacing was somewhat wider.