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미경산 한우에 있어서 수태율증진을 위한 hCG처리효과

  • 최선호;성환후;양병철;임기순;노환국;장유민;장원경
    • Proceedings of the KSAR Conference
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    • 2001.03a
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    • pp.82-82
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    • 2001
  • 본 연구는 한우에 있어서 인공수정후 수태율증진을 위한 기초자료를 확보할 목적으로 성숙 미경산 한우의 발정동기화를 위해 CIDR(EAZI-BREED CIDR Plus, USA)를 7일간 질내에 삽입하였고, CIDR처리 제 6일째에 PGF2$\alpha$(lutlyase, USA)제제 5 $m\ell$을 근육주사하여 발정이 유기된 92%의 개체를 인공수정을 실시하였다. 수태율증진을 위해 무처리구를 두었고, hCG처리구(Chorulon, Intervet, Netherlands)는 2000IU를 근육 주사하였으며, CIDR처리구에는 Estradiol-17$\beta$의 캡슐을 제거한 CIDR를 수정후 7일부터 일주일간 질내에 삽입 처리하여 각 처리당 15두씩 총 45두의 한우를 실험에 공시하였다. 발정이 유기된 개체는 인공수정후 30일까지 2일 간격으로 채혈하여 혈중 Progesterone, IGF, IGF-II 및 cortisol 농도를 RIA법으로 분석하였으며 수정 후 60일 이후에는 직장검사법으로 임신감정을 실시하였다. 수정후 수태율은 대조구와 CIDR 처리구에서는 평균 62%였으나 hOG처리구는 73%로서 대조구에 비해 유의적으로 수태율이 높게 나타났다. 이때의 혈중 progesterone농도를 분석한 결과, 대조구에 CIDR 처리구의 수정후 7일째부터 증가하기 시작하여 제 12일째에서 평균 5.5ng/$m\ell$까지 증가하다가 그 이후 재발정 예정일일 21일째에 다소 감소되다가 다시 증가되어 일정한 수준으로 유지되었다 그러나 hCG처리구의 경우 수정후 5일부터 progesterone이 증가하다가 제 15일까지 약 10ng/$m\ell$까지 높은 progesterone이 유지되었다. 이와 같은 결과로 보아 hCG는 혈중 progesterone농도를 증가시킴으로써 난소내 임신황체의 progestorone분비 능을 촉진시키는 작용을 하는 것으로 사료되나, 한편 혈중 IGF I과 IGF-II농도는 대조구, hCG처리구 및 CIDR 처리구간의 차이가 없이 수정 후 제10일까지는 다소 높은 수준이었으나 그 이후 감소되는 현상으로 혈중 progesterone농도와는 부의 상관관계를 보였다. 따라서 IGF-I과 IGF-II는 혈중 progesterone의 농도를 인위적으로 조절하거나 황체의 progesterone분비기능을 직접 조절하는 역할은 하지 않는 것으로 사료되며, 특히 초기 임신의 수태율에 직접적으로 영향이 없는 것으로 사료된다. 또한 혈중 cortisol농도는 처리간의 차이는 확인할 수 없으나 임신과 비임신간의 혈중 cortisol농도는 유의적으로 차이가 있는 것으로 나타났다. 본 실험의 결과로 인공수정이나 수정란이식 및 체세포복제 수정란뿐만 아니라 형질전환 수정란의 이식후 수태율을 증진시켜 첨단기술의 조기정착을 위해 이식 후 7일째나 인공수정 후 7일째 hCG제제를 근육주사로 간단하게 처리함으로써 수태율을 크게 개선될 수 있으며 이것은 난소의 황체기능 즉, 황체로부터 충분한 progesterone을 분비할 수 있는 내분비적 환경을 제공하는 것으로 사료된다.

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A Comparison of the Metanarrative and East Timor's Local Narrative in Indonesia under the Suharto's Regime (인도네시아의 메타내러티브와 동티모르의 로칼내러티브의 서술구조 비교)

  • Song, Seung-Won
    • Journal of International Area Studies (JIAS)
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    • v.15 no.1
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    • pp.155-180
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    • 2011
  • This paper aims at comparing the metanarrative and East Timor's local narrative in Indonesia during the Suharto's regime. Although these history writings have different political goals, the patterns of writings are ironically similar. Both of the history writings show strong nationalistic history writing patterns. Yet, in the writings, these histories place different interpretations on the historical events. In the metanarrative, local dynamics are seen through the diagrams of the nation and nationhood. This narrative finds the roots of the "ethnie" from some kingdoms in Java and Sumatra. These kingdoms, which throve based on the Hindu-Buddhist culture, achieved a territorial unity to a degree, covering some parts of Java and Sumatra. The glorious past disappeared with the advent of the colonial rule. The metanarrative then emphasizes the unity of the ethnic groups in the archipelago, which fiercely resisted against the colonial exploitation and oppression. By this, these ethnic groups were defined as "the masses," the collective identity, which had a same goal to achieve the national independence. In addition, some local histories, which took positive attitudes toward the European forces, were simply left out from the metanarrative. All the separatist movements taking place in the republic were also described as the anti-unifying forces. On the other hand, the goal of the history-writing in East Timor was to enhance the sense of nationalism and create the perception of the "East Timorese." The fundamental aim was the separation from Indonesia. In the narrative, the nationalist politicians overcame the problem of the non-existence of any memories of the glorious past with the awakening of the idea of "the imagined gloriousness of the past if there was no colonial rule." In addition, the narrative overemphasizes the memory of the colonial rule for 450 years under the Portuguese rule in order to stress the fact that it was the colony of Portugal, not of the Netherlands. Finally, the narrative shows how the East Timorese collectively fell to the status of slaves. By this, the political leaders of East Timor evoked the notion that it was recolonized by Indonesia, under which the East Timorese were demoted to the status of slaves. This notion of "slave-master" relationship then became the motives for the independence struggles in East Timor.

Present status and prospect for development of mushrooms in Korea

  • Jang, Kab-Yeul;Oh, Youn-Lee;Oh, Minji;Im, Ji-Hoon;Lee, Seul-Ki;Kong, Won-Sik
    • 한국균학회소식:학술대회논문집
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    • 2018.05a
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    • pp.27-27
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    • 2018
  • The production scale of mushroom cultivation in Korea is approximately 600 billion won, which is 1.6% of the Korean gross agricultural output. Annually, ca. 190,000 tons of mushrooms are harvested in Korea. Although the numbers of mushroom farms and cultivators are constantly decreasing, the total mushroom yields are increasing due to the large-scale cultivation facilities and automation. The recent expansion of the well-being trend causes increase in mushroom consumption in Korea: annual per capita consumption of mushroom was 3.9kg ('13) that is a little higher than European's average. Thus the exports of mushrooms, mainly Flammulina velutipes and Pleurotus ostreatus, have been increased since the middle of 2000s. Recently, however, it is slightly reduced. However, Vietnam, Hong Kong, the United States, the Netherlands and continued to export, and the country has increased recently been exported to Australia, Canada, Southeast Asia and so on. Canned foods of Agaricus bisporus was the first exports of the Korean mushroom industry. This business has reached the peak of the sale in 1977-1978. As Korea initiated trade with China in 1980, the international prices of mushrooms were sharply fall that led to shrink the domestic markets. According to the high demand to develop new items to substitute for A. bisporus, oyster mushroom (Pleurotus ostreatus) was received the attention since it seems to suit the taste of Korean consumers. Although log cultivation technique was developed in the early 1970s for oyster mushroom, this method requires a great deal of labor. Thus we developed shelf cultivation technique which is easier to manage and allows the mass production. In this technique, the growing shelf is manly made from fermented rice straw, that is the unique P. ostreatus medium in the world, was used only in South Korea. After then, the use of cotton wastes as an additional material of medium, the productivity. Currently it is developing a standard cultivation techniques and environmental control system that can stably produce mushrooms throughout the year. The increase of oyster mushroom production may activate the domestic market and contribute to the industrial development. In addition, oyster mushroom production technology has a role in forming the basis of the development of bottle cultivation. Developed mushroom cultivation technology using bottles made possible the mass production. In particular, bottle cultivation method using a liquid spawn can be an opportunity to export the F.velutipes and P.eryngii. In addition, the white varieties of F.velutipes were second developed in the world after Japan. We also developed the new A.bisporus cultivar "Sae-ah" that is easy to grown in Korea. To lead the mushroom industry, we will continue to develop the cultivars with an international competitive power and to improve the cultivation techniques. Mushroom research in Korea nowadays focuses on analysis of mushroom genetics in combination with development of new mushroom varieties, mushroom physiology and cultivation. Further studied are environmental factors for cultivation, disease control, development and utilization of mushroom substrate resources, post-harvest management and improvement of marketable traits. Finally, the RDA manages the collection, classification, identification and preservation of mushroom resources. To keep up with the increasing application of biotechnology in agricultural research the genome project of various mushrooms and the draft of the genetic map has just been completed. A broad range of future studies based on this project is anticipated. The mushroom industry in Korea continually grows and its productivity rapidly increases through the development of new mushrooms cultivars and automated plastic bottle cultivation. Consumption of medicinal mushrooms like Ganoderma lucidum and Phellinus linteus is also increasing strongly. Recently, business of edible and medicinal mushrooms was suffering under over-production and problems in distribution. Fortunately, expansion of the mushroom export helped ease the negative effects for the mushroom industry.

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A Study on Glass Mirror Trade and its Characteristics of Craft after Joseon Dynasty (조선 후기 유리거울의 수입과 공예품의 특징)

  • Park, Jinkyung
    • Korean Journal of Heritage: History & Science
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    • v.52 no.4
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    • pp.206-225
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    • 2019
  • This paper examines the trade and development aspects of glass mirrors through the literature records of the Joseon Dynasty, and studies the characteristics of existing glass mirror crafts by referring to the terms and types shown in the literature. The glass mirror in the records had called western mirrors(西洋鏡, 洋鏡), glass mirrors(玻璃鏡, 玻瓈鏡), stone mirrors(石鏡), etc. Glass mirrors were imported mainly through trade with Russia and the Qing Dynasty since the 17th century and were banned from importation in the late Joseon Dynasty. These mirrors were something new that caused a great stirring in Joseon society in the 18th century, and in the 19th century, it grew larger as a commodity needed for everyday life, especially with trade with Japan. At that time, glass mirrors were used for various purposes, such as installing large glass at a store, which were not the standard mirror usage of confirming one's appearance. These mirrors surprised Koreans in Joseon who experienced them at Yanjing Liulichang(燕京 琉璃廠) in the 18th and 19th centuries. As a result, the demand for glass mirrors rapidly increased and quickly surpassed that of bronze mirrors. Consequentially, new crafts using glass mirrors instead of bronze mirrors in Joseon began to be produced and used after the 18th century. In particular, integrated flat boards of glass mirrors were developed as crafts used indoors. It was convenient to use the hair comb box, a long-time presence in Joseon society, with the bronze mirror. This kind of mirror remained apparent in various genre paintings, including the Taepyeong Seongsido(太平城市圖, 'A Thriving City in a Peaceful Era') collected the National Museum of Korea which reflect its populism of the times. Also, the Mirror Stand(鏡臺) used in the Qing Period was produced in Joseon, but there was a difference in the way of making the drawers and box shapes between two nations. On the other hand, the Face Mirror(面鏡) was made to look at the face. Various crafts made with the aesthetic sense of Joseon, such as the ox horn inlaying craft technique, were produced with auspicious designs. In the 19th century, glass mirrors were imported from European countries, such as France, Denmark, the Netherlands, and the United Kingdom, however after the end of the 19th century Japanese crafts were popular. Glass mirrors, which were popular in the Meiji and Taisho eras of Japan, were imported and also the Mirror Screen(鏡屛) using large glass mirrors were used. In particular, the mirror screen had developed wood furniture since the previous time, which were used for banquets and large spaces, such as the drawing room, and were imported from China and Japan. In addition, the western architectural effect of attaching a mirror to the wall was also attempted to adjust the brightness of the space and introduce another image and scenery in the mirror. This was done at Deoksugung Palace's Seokjojeon.

The Comparison of Basic Science Research Capacity of OECD Countries

  • Lim, Yang-Taek;Song, Choong-Han
    • Journal of Technology Innovation
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    • v.11 no.1
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    • pp.147-176
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    • 2003
  • This Paper Presents a new measurement technique to derive the level of BSRC (Basic Science and Research Capacity) index by use of the factor analysis which is extended with the assumption of the standard normal probability distribution of the selected explanatory variables. The new measurement method is used to forecast the gap of Korea's BSRC level compared with those of major OECD countries in terms of time lag and to make their international comparison during the time period of 1981∼1999, based on the assumption that the BSRC progress function of each country takes the form of the logistic curve. The US BSRC index is estimated to be 0.9878 in 1981, 0.9996 in 1990 and 0.99991 in 1999, taking the 1st place. The US BSRC level has been consistently the top among the 16 selected variables, followed by Japan, Germany, France and the United Kingdom, in order. Korea's BSRC is estimated to be 0.2293 in 1981, taking the lowest place among the 16 OECD countries. However, Korea's BSRC indices are estimated to have been increased to 0.3216 (in 1990) and 0.44652 (in 1999) respectively, taking 10th place. Meanwhile, Korea's BSRC level in 1999 (0.44652) is estimated to reach those of the US and Japan in 2233 and 2101, respectively. This means that Korea falls 234 years behind USA and 102 years behind Japan, respectively. Korea is also estimated to lag 34 years behind Germany, 16 years behind France and the UK, 15 years behind Sweden, 11 years behind Canada, 7 years behind Finland, and 5 years behind the Netherlands. For the period of 1981∼1999, the BSRC development speed of the US is estimated to be 0.29700. Its rank is the top among the selected OECD countries, followed by Japan (0.12800), Korea (0.04443), and Germany (0.04029). the US BSRC development speed (0.2970) is estimated to be 2.3 times higher than that of Japan (0.1280), and 6.7 times higher than that of Korea. German BSRC development speed (0.04029) is estimated to be fastest in Europe, but it is 7.4 times slower than that of the US. The estimated BSRC development speeds of Belgium, Finland, Italy, Denmark and the UK stand between 0.01 and 0.02, which are very slow. Particularly, the BSRC development speed of Spain is estimated to be minus 0.0065, staying at the almost same level of BSRC over time (1981 ∼ 1999). Since Korea shows BSRC development speed much slower than those of the US and Japan but relative]y faster than those of other countries, the gaps in BSRC level between Korea and the other countries may get considerably narrower or even Korea will surpass possibly several countries in BSRC level, as time goes by. Korea's BSRC level had taken 10th place till 1993. However, it is estimated to be 6th place in 2010 by catching up the UK, Sweden, Finland and Holland, and 4th place in 2020 by catching up France and Canada. The empirical results are consistent with OECD (2001a)'s computation that Korea had the highest R&D expenditures growth during 1991∼1999 among all OECD countries ; and the value-added of ICT industries in total business sectors value added is 12% in Korea, but only 8% in Japan. And OECD (2001b) observed that Korea, together with the US, Sweden, and Finland, are already the four most knowledge-based countries. Hence, the rank of the knowledge-based country was measured by investment in knowledge which is defined as public and private spending on higher education, expenditures on R&D and investment in software.

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Etiological Properties and Coat Protein Gen Analysis of Potato Virus Y Occuring in Potatoes of Korea (우리나라 감자에 발생하는 PVY의 병원학적 특성 및 외피단백질 유전자 분석)

  • ;Richard M. Bostock
    • Proceedings of the Korean Society of Plant Pathology Conference
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    • 1995.06b
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    • pp.77-96
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    • 1995
  • To obtain basic informations for the improvement of seed potato production in Korea, some etiological properties of potato virus Y(PVY) distributed in the major seed potato production area(Daekwanryeong) were characterized, and the nucleotide and amino acid sequences of the coat protein gene of the PVY strains isolated were analyzed. PVY strains in Daekwonryeong, an alpine area, were identified to be two strains, PVYo and PVYN by symptoms of indicator plants, and their distribution in potato fields was similar. Major symptom on potato varieties by PVY was grouped as either mosaic alone or mosaic accompanied with veinal necrosis in the lower leaves. The symptom occurrence of the two symptoms was similar with Irish Cobbler, but Superior showed a higher rate of mosaic symptom than the other. The PVY strain which was isolated from potato cv. Superior showing typical mosaic symptoms produced symptoms of PVY-O on the indicator plants of Chenopodium amaranticolor, Nicotiana tabacum cv. Xanthi nc and Physalis floridana, but no symptom o Capsicum annum cv. Ace. Moreover, results from the enzyme-linked immunosorbent assay with monoclonal and polyclonal antibodies showed that the isolated PVY reacts strongly with PYV-O antibodies but does not react specifically with PVY-T antibodies. The purified virus particles were flexious with a size of 730$\times$11nm. On the basis of the above characteristics, the strain was identified to be a PVY-O and named as of PVY-K strain. The flight of vector aphids was observed in late May, however, the first occurrence of infected plants was in mid June with the bait plants surrounded with PVY-infected potato plants and early July with the bait plants surrounded with PVY-free potato plants. PVY infection rates by counting symptoms on bait plants (White Burley) were 1.1% with the field surrounded with PVY-free potato plants and 13.7% the fields surrounded with PVY-infected potato plants, showing the effect of infection pressure. The propagated PVY-K strain on tobacco(N. sylvestris) was purified, and the RNA of the virus was extracted by the method of phenol extraction. The size of PVY-K RNA was measured to be 9, 500 nucleotides on agarose gel electrophoresis. The double-stranded cDNAs of PVY-K coat protein(CP) gene derived by the method of polymerase chain reaction were transformed into the competent cells of E. coli JM 109, and 2 clones(pYK6 and pYK17) among 11 clones were confirmed to contain the full-length cDNA. Purified plasmids from pYK17 were cut with Sph I and Xba I were deleted with exonuclease III and were used for sequencing analysis. The PVY-K CP gene was comprised of 801 nucleotides when counted from the clevage site of CAG(Gln)-GCA(Ala) to the stop codon of TGA and encoded 267 amino acids. The molecular weight of the encoded polypeptides was calculated to be 34, 630 daltons. The base composition of the CP gene was 33.3% of adenine, 25.2% of guanine, 20.1% of cytosine and 21.4% of uracil. The polypeptide encoded by PVY-K CP gene was comprised of 22 alanines, 20 threonines, 19 glutamic acids and 18 glycines in order. The homology of nucleotide sequence of PVY-K CP gene with those of PVY-O(Japan), PVY-T(Japan), PVY-TH(Japan), PVYN(the Netherlands), and PVYN(France) was represented as 97.3%, 88.9%, 89.3%, 89.6% and 98.5%, respectively. The amino acid sequence homology of the polypeptide encoded by PVY-K CP gene with those encoded by viruses was represented as 97.4%, 92.5%, 92.9%, 92.9%, and 98.5%, respectively.

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Patients with brain metastases the usefulness of contrast-enhanced FLAIR images after delay (뇌전이 환자의 조영 증강 후 지연 FLAIR 영상의 유용성)

  • Byun, Jae-Hu;Park, Myung-Hwan;Lee, Jin-Wan
    • Korean Journal of Digital Imaging in Medicine
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    • v.16 no.1
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    • pp.13-19
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    • 2014
  • Purpose: FLAIR image is beneficial for the diagnosis of various bran diseases including ischemic CVS, brain tumors and infections. However the border between the legion of brain metastasis and surrounding edema may not be clear. Therefore, this study aims to investigate the practical benefits of delayed imaging by comparing the image from a patient with brain metastasis before a contrast enhancement and the image 10 minutes after a contrast enhancement. Materials and methods: Of the 92 people who underwent MRI brain metastases in suspected patients 13 people in three patients there is no video to target the 37 people confirmed cases, and motion artifacts brain metastases in our hospital June-December 2013, 18 people measurement position except for the three incorrect patient (male: 11 people, female: 7 people, average age: 60 years) in the target, test equipment, 3.0T MR System (ACHIEVA Release, Philips, I was 8ChannelSENSE Head Coil use Best, and the Netherlands). TR 11000 ms, TE 125 ms, TI2800 ms, Slice Thickness 5 mm, gap 5 mm, is a Slice number 21, the parameters of the 3D FFE, T2 FLAIR variable that was used to test, TR 8.1 ms, TE 3.7 ms, Slice number 240 I set to. The experiment was conducted by acquiring the FLAIR prior to contrast enhancement (heretofore referred to as Pre FLAIR), and acquiring the 3D FFE CE five minutes after the contrast enhancement, and recomposing the images in an axial plane of S/T 3mm, G 0mm (heretofore referred to as MPR TRA CE). Using the FLAIR 10 minutes after the contrast enhancement (heretofore referred to as Post FLAIR) and Pi-View, a retrospective study was conducted. Using MRIcro on the image of a patient confirmed for his diagnosis, the images before and after the contrast media, as well as the CNR and SNR of the MPR TRA CE images of the lesion and the site absent of lesion were compared and analyzed using a one-way analysis of variance. Results: CNR for Pre FLAIR and Post FLAIR were 34.35 and 60.13, respectively, with MPR TRA CE at 23.77 showing no significant difference (p<0.050). Post-experiment analysis shows a difference between Pre FLAIR and Post FLAIR in terms of CNR (p<0.050), but no difference in CNR between Post FLAIR and MPR TRA CE (p>0.050), indicating that the contrast media had an effect only on Pre FLAIR and Post FLAIR. The SNR for the normal site Pre FLAIR was 106.43, and for the lesion site 140.79. Post FLAIR for the normal site was 107.79, and for the lesion site 167.91. MPR TRA CE for the normal site was 140.23 and for the lesion site 183.19, showing significant difference (p<0.050), and post-experiment analysis shows that there was a difference in SNR only on the lesion sites for Pre FLAIR and Post FLAIR (p<0.050). There was no difference in SNR between the normal site and lesion site for Post FLAIR and MPR TRA CE, indicating no effect from the contrast media (p>0.050). Conclusions: This experiment shows that Post FLAIR has a higher contrast than Pre FLAIR, and a higher SNR for lesions, It was not not statistically significant and MPR TRA CE but CNR came out high. Inspection of post-contrast which is used in a high magnetic field is frequently used images of 3D T1 but, since the signal of the contrast medium and the blood flow is included, this method can be diagnostic accuracy is reduced, it is believed that when used in combination with Post FLAIR, and that can provide video information added to the diagnosis of brain metastases.

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Service Philosophy as Wisdom for Human Society Development (인류사회 발전 지혜로서의 서비스철학)

  • Hyunsoo Kim
    • Journal of Service Research and Studies
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    • v.12 no.4
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    • pp.1-18
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    • 2022
  • This study was conducted to prove that the service philosophy is the development principle of human society in the service age. From ancient times to the present, the service philosophy was tried to show the wisdom of the development of human society in all earth spaces including the East and the West. In addition, it tried to prove that the service philosophy was at the center of the development wisdom of many countries and individuals who flickered on all space on earth and all human time. The study showed that the differences between countries were in software rather than hardware. Furthermore, it was analyzed that countries with a service philosophy embedded in the center of software such as spirit and culture made a great contribution to human society. The cases of Greece and Rome, the Republic of Venice, the Republic of the Netherlands, followed by the United States and modern Korea prove this, and the Soviet Union can be seen to disprove it. The former was a society in which state-run software was strong, and the latter was a society in which hardware was strong. There is a big difference between the case of the state, which citizens have autonomously organized and operated, and the case of the upper-level state-led operation. Since the leadership of the upper classes is not based on the service philosophy, the accumulated software power is weak, so it can be said that the accumulation of wisdom in human society is weak. Therefore, while the essence of human society so far has been a society of self-centered animal ecosystems led by selfishness, the human society in the service age from now on can be said to be a society of plant ecosystems where mutual respect and self-centeredness coexist. Just as the society centered on the service philosophy in the past human society prospered and left a greater legacy to mankind, it is suggested that the human society in the future service era should be a human society of a plant ecosystem centered on the service philosophy. Further in-depth studies related to this are needed in the future.

Analysis on the Displacement Constraints of Frames for Plastic Film Greenhouse (플라스틱 필름 온실용 구조재의 변위제한 검토)

  • Yun, Sung-Wook;Choi, Man-Kwon;Lee, Siyoung;Kang, Donghyeon;Kim, Hyeon-Tae;Yoon, Yong-Cheol
    • Journal of agriculture & life science
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    • v.50 no.1
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    • pp.273-281
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    • 2016
  • In this study, after carrying out a bending test that targeted the frames of plastic film greenhouse, the load-displacement relationship was analyzed to be used as basic data to develop greenhouse construction and maintenance guidelines. As a result, regardless of the shapes of the specimen, the yield and the maximum load increased as the size of the specimen increased. The displacement also showed the same pattern. A steel pipe showed lower yield and maximum load than a square pipe, and the displacement was large. In the steel pipe case, the displacement under the yield and maximum load was in the range of approximately 1.42-4.20mm and 5.80-24.13mm, respectively. In the square pipe case, the displacement under the yield and maximum load was in the range of approximately 1.62-3.00mm and 3.13-8.01mm, respectively. Further, a large difference was observed between the result of this test and the values calculated by a conventionally provided standard. In particular, not much difference was found from the result of this test in the case of a purlin member from the values provided by previous researches. However, a large difference was observed in the column or main rafter members. Furthermore, when a wide-span and venlo type, which is a glasshouse, was used as a target(h/100 and h/80), the displacement under the yield and maximum load was approximately 28.0mm and 35.0mm, respectively, which showed a large difference compared with the Netherlands standard(14.0mm) of a glasshouse. Further, in the main rafter case, a large difference was observed in the displacement limit according to the width(i.e., span) of the greenhouse where members are used. Therefore, because the displacement limit can vary depending on various factors such as type, form, and size of a greenhouse, we determined that studies or tests that consider these factors should be carried out to reflect them in the construction and maintenance of greenhouses.

Changes in Growth and Bioactive Compounds of Lettuce According to CO2 Tablet Treatment in the Nutrient Solution of Hydroponic System (수경재배 양액 내 탄산정 처리에 의한 상추의 생육 및 생리활성물질 함량 변화)

  • Bok, Gwonjeong;Noh, Seungwon;Kim, Youngkuk;Nam, Changsu;Jin, Chaelin;Park, Jongseok
    • Journal of Bio-Environment Control
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    • v.30 no.1
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    • pp.85-93
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    • 2021
  • In hydroponic cultivation, in order to investigate the change of lettuce growth and physiologically active substances through CO2 tablet treatment in nutrient solution, we used a solid carbonated tablets commercially available in the Netherlands. The experiment consisted of 0.5-fold, 1-fold, and 2-fold treatment groups with no treatment as a control. As a result, the atmospheric CO2 concentration in the chamber after CO2 tablet treatment showed the highest value at 472.2 µL·L-1 in the 2-fold treatment zone immediately after treatment, and the pH in the nutrient solution decreased the most to pH 6.03 in the 2-fold treatment zone. After that, over time, the CO2 concentration and pH recovered to the level before treatment. Leaf width and leaf area of lettuce showed the highest values of 17.1cm and 1067.14 ㎠ when treated 2-fold with CO2 tablet, while fresh weight and dry weight of the above-ground part were highest at 63.87 g and 3.08 g in 0.5-fold treatment. The root length of lettuce was the longest (28.4 cm) in the control, but there was no significant difference in the fresh weight and the dry weight among the treatments. Apparently, it was observed that the root length of the lettuce was shortened by CO2 tablet treatment and a lot of side roots occurred. In addition, there was a growth disorder in which the roots turned black, but it was found that there was no negative effect on the growth of the above-ground part. As a result of analyzing the bioactive compounds of lettuce by CO2 tablet treatment, chlorogenic acid and quercetin were detected. As a result of quantitative analysis, chlorogenic acid increased by 249% compared to the control in 1-fold treatment, but quercetin decreased by 37%. As a result of comparing the DPPH radical scavenging ability showing antioxidant activity, the control and 0.5-fold treatment showed significantly higher values than the 1-fold and 2-fold treatments. This suggests that carbonated water treatment is effective in increasing the growth and bioactive compounds of hydroponic lettuce.