• Title/Summary/Keyword: Primary response

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Disappearance of Hysteria(Conversion Disorder) and the Evolutionary Brain Discord Reaction Theory (히스테리아(전환장애)의 소실과 진화적 뇌신경 부조화 반응 가설)

  • Song, Ji Young
    • Korean Journal of Psychosomatic Medicine
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    • v.24 no.1
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    • pp.28-42
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    • 2016
  • Objectives : The author tried to find out reasons why and how hysteria(and conversion disorder) patient numbers, which were so prevalent even a few decades ago, have decreased and the phenotype of symptoms have changed. Methods : The number of visiting patients diagnosed with conversion disorder and their phenotype of symptoms were investigated through chart reviews in a psychiatric department of a University hospital for the last 12 years. Additionally, the characteristics of conversion disorder patients visiting the emergency room for last 2 years were also reviewed. Those results were compared with previous research results even if it seemed to be an indirect comparisons. The research relied on Briquet P. and Charcot JM's established factors of the vicissitudes of hysteria(and conversion disorder) which has been the framework for more than one hundred and fifty years since hysteria has been investigated. Results : The author found decreased numbers and changes of the phenotype of the hysteria patients(and conversion disorder) over the last several decades. The decreased numbers and changes of the symptoms of those seemed to be partly due to several issues. These issues include the development of the diagnostic techniques to identify organic causes of hysteria, repeated changes to the symptom descriptions and diagnostic classification, changes of the brain nervous functions in response to negative emotions, and the influence of human evolution. Conclusions : The author proposed that the evolutionary brain discord reaction theory explains the causes of disappearance of and changes to symptoms of hysteria(conversion disorder). Most patients with hysteria(conversion disorder) have been diagnosed in the neurological department. For providing more appropriate treatment and minimizing physical disabilities to those patients, psychiatrists should have a major role in cooperating not only with primary care physicians but with neurologists. The term 'hysteria' which had been used long ago should be revived and used as a term to describe diseases such as somatic symptom disorder, functional neurological symptoms, somatization, and somatoform disorders, all of which represent almost the same vague concept as hysteria.

Pathophysiological Regulation of Vascular Smooth Muscle Cells by Prostaglandin F2α-dependent Activation of Phospholipase C-β3 (Prostaglandin F2α 의존적 phospholipase C-β3 활성화에 의한 혈관평활근세포의 병태생리 조절 연구)

  • Kang, Ki Ung;Oh, Jun Young;Lee, Yun Ha;Lee, Hye Sun;Jin, Seo Yeon;Bae, Sun Sik
    • Journal of Life Science
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    • v.28 no.12
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    • pp.1516-1522
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    • 2018
  • Atherosclerosis is an obstructive vessel disease mainly caused by chronic arterial inflammation to which the proliferation and migration of vascular smooth muscle cells (VSMCs) is the main pathological response. In the present study, the primary responsible inflammatory cytokine and its signaling pathway was investigated. The proliferation and migration of VSMCs was significantly enhanced by the prostaglandin $F_{2{\alpha}}$ ($PGF_{2{\alpha}}$), while neither was affected by tumor necrosis factor ${\alpha}$. Prostacyclin $I_2$ was seen to enhance the proliferation of VSMCs while simultaneously suppressing their migration. Both prostaglandin $D_2$ and prostaglandin $E_2$ significantly enhanced the migration of VSMCs, however, proliferation was not affected by either of them. The proliferation and migration of VSMCs stimulated by $PGF_{2{\alpha}}$ progressed in a dose-dependent manner; the $EC_{50}$ value of both proliferation and migration was $0.1{\mu}M$. VSMCs highly expressed the phospholipase isoform $C-{\beta}3$ ($PLC-{\beta}3$) while others such as $PLC-{\beta}1$, $PLC-{\beta}2$, and $PLC-{\beta}4$ were not expressed. Inhibition of the PLCs by U73122 completely blocked the $PGF_{2{\alpha}}$-induced migration of VSMCs, and, in addition, silencing $PLC-{\beta}3$ significantly diminished the $PGF_{2{\alpha}}$-induced proliferation and migration of VSMCs. Given these results, we suggest that $PGF_{2{\alpha}}$ plays a crucial role in the proliferation and migration of VSMCs, and activation of $PLC-{\beta}3$ could be involved in their $PGF_{2{\alpha}}$-dependent migration.

Smart farm development strategy suitable for domestic situation -Focusing on ICT technical characteristics for the development of the industry6.0- (국내 실정에 적합한 스마트팜 개발 전략 -6차산업의 발전을 위한 ICT 기술적 특성을 중심으로-)

  • Han, Sang-Ho;Joo, Hyung-Kun
    • Journal of Digital Convergence
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    • v.20 no.4
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    • pp.147-157
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    • 2022
  • This study tried to propose a smart farm technology strategy suitable for the domestic situation, focusing on the differentiation suitable for the domestic situation of ICT technology. In the case of advanced countries in the overseas agricultural industry, it was confirmed that they focused on the development of a specific stage that reflected the geographical characteristics of each country, the characteristics of the agricultural industry, and the characteristics of the people's demand. Confirmed that no enemy development is being performed. Therefore, in response to problems such as a rapid decrease in the domestic rural population, aging population, loss of agricultural price competitiveness, increase in fallow land, and decrease in use rate of arable land, this study aims to develop smart farm ICT technology in the future to create quality agricultural products and have price competitiveness. It was suggested that the smart farm should be promoted by paying attention to the excellent performance, ease of use due to the aging of the labor force, and economic feasibility suitable for a small business scale. First, in terms of economic feasibility, the ICT technology is configured by selecting only the functions necessary for the small farm household (primary) business environment, and the smooth communication system with these is applied to the ICT technology to gradually update the functions required by the actual farmhouse. suggested that it may contribute to the reduction. Second, in terms of performance, it is suggested that the operation accuracy can be increased if attention is paid to improving the communication function of ICT, such as adjusting the difficulty of big data suitable for the aging population in Korea, using a language suitable for them, and setting an algorithm that reflects their prediction tendencies. Third, the level of ease of use. Smart farms based on ICT technology for the development of the Industry6.0 (1.0(Agriculture, Forestry) + 2.0(Agricultural and Water & Water Processing) + 3.0 (Service, Rural Experience, SCM)) perform operations according to specific commands, finally suggested that ease of use can be promoted by presetting and standardizing devices based on big data configuration customized for each regional environment.

Anti-stress and Sleep-enhancing Effects of Ptecticus tenebrifer Water Extract Through the Regulation of Corticosterone and Melatonin Levels (코르티코스테론 및 멜라토닌 수치 조절을 통한 동애등에 물 추출물의 항스트레스 및 수면 개선 효과)

  • Oh, Dool-Ri;Ko, Haeju;Hong, Seong Hyun;Kim, Yujin;Oh, Kyo-Nyeo;Kim, Yonguk;Bae, Donghyuck
    • Journal of Life Science
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    • v.32 no.8
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    • pp.601-610
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    • 2022
  • P. tenebrifer (PT) belongs to the Diptera order and Stratiomyidae family. Recently, insect industry have been focused as food, animal feed and environmental advantages. γ-aminobutyric acid (GABA) and melatonin have been associated with regulating sleep and depression. GABA is the primary inhibitory neurotransmitter and is synthesized via biotransformation of monosodium glutamate (MSG) to GABA by lactic acid bacteria. In this study, we first used a GABA-enhanced PT extract, wherein GABA was enhanced by feeding MSG to PT. The underlying mechanisms preventing stress and insomnia were investigated in a corticosterone (CORT)-induced endoplasmic reticulum (ER) stress and chronic restraint stress (CRS)-exposed mouse model, as well as in pentobarbital (45 mg/kg)-induced sleep behaviors in mice. In the present study, the GABA peak was detected in high-performance liquid chromatography-evaporative light scattering detector (HPLC-ELSD) analysis and showed in Ptecticus tenebrifer water extract (PTW) but not in non-PTW extract. The results showed that PTW and Ptecticus tenebrifer with 70% ethanol extract (PTE) exerted neuroprotective effects by protecting against CORT-induced downregulation of phosphorylated extracellular signal-regulated kinase 1/2 (ERK1/2) and cAMP-response element binding protein (CREB) expression. In addition, PTW (300 mg/kg) significantly reduced CORT levels in CRS-exposed mice. Furthermore, PTW (100 and 300 mg/kg) significantly reduced sleep latency and increased total sleep duration in pentobarbital (45 mg/kg)-induced sleeping behaviors, which was related to serum melatonin levels. In conclusion, our results suggest that PTW exerts anti-stress and sleep-enhancing effects by regulating serum CORT and melatonin levels.

Factors Affecting the Registration and Access Levels of the Pilot Project for the General Physician System among People with Disabilities (장애인 건강주치의 시범사업 수요자의 등록 및 이용수준 영향 요인 분석)

  • Eunhee Choe;Yeojeong Gu;Seungji Lim
    • Health Policy and Management
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    • v.34 no.2
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    • pp.185-195
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    • 2024
  • Background: Disabled people have particularly restricted access to health care. In response to this, the pilot project for the general physician (GP) system for disabled people was implemented in 2018, based on the rights of people with disability to the Health Act in South Korea. However, its participants were 0.2% among the total of those with severe disabilities in 2021. Therefore, this study examined the factors related to registering with a GP and the access level to its services to suggest implications for activating the participation of disabled people. Methods: We analyzed factors affecting the registration with a GP and the number of using the services among the participants of the GP system during May 2018 and December 2021 by conducting hierarchical logistic regression and hierarchical regression. The data were linked with the national health insurance data to examine various predictors, including disability types, socioeconomic status, health status, and GP registration. Results: As a result of analyzing the factors affecting whether or not to register for the pilot project, those with disabilities (physical disabilities, brain lesions, visual, intellectual, mental, and autistic disability) eligible for disability care (odds ratio [OR], 4.157) than other disability, and those living in metropolitan (OR, 4.330) or cities (OR, 3.332) than rural residences were highly likely to enroll the pilot study. Health-related variables also predicted the registration status of the pilot project. The predictors related to GP enrollment types (membership type: general health or disability care, GP's affiliation: clinics or hospitals) significantly influenced levels of access to services. Conclusion: It is necessary to develop the GP project for disabled people by considering the variation in types of disability, residences, and health. Further study will be needed to investigate the impact of GPs on the level of participation among disabled people.

Understanding Management of Technology(MOT) in South Korea through an Analysis of Graduate MOT Programs' Curricula (한국의 기술경영전문대학원의 교과과정을 통해 본 한국적 기술경영학의 정체성)

  • Taehyun Jung;Gyu Hyun Kwon;Kwon Yeong-il;Hyunkyu Park;Kyootai Lee;Jeonghwan Jeon
    • Journal of Technology Innovation
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    • v.31 no.3
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    • pp.39-73
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    • 2023
  • The field of Management of Technology(MOT) emerged in response to the need for research management within U.S. public research institutions during the 1960s. Since its inception, it has proliferated significantly, being practiced in more than 809 institutions globally and over 19 institutions in Korea, encompassing both research and educational endeavors. Particularly noteworthy is the substantial investment of government resources, primarily channeled through the Ministry of Industry since 2007, which has expeditiously established a comprehensive framework for cultivating graduate-level MOT expertise, marked by both quantitative and qualitative advancements. The educational curriculum in the realm of Korean MOT deviates from foreign counterparts through distinctive pathways, exemplified by its emphasis on industry practice-oriented educational programs, standardization and isomorphism across different schools, as well as its interconnectedness with proximate academic disciplines. This research systematically undertakes an analysis of the curriculum in Korean MOT graduate schools, thereby ascertaining its intrinsic identity and distinct attributes. In this endeavor, a comprehensive examination of eleven principal MOT textbooks(three in Korean and eight in English) is conducted to delineate the primary content of the curriculum across seven thematic domains. Moreover, the study deliberates on its differentiation from neighboring academic disciplines and the definitional attributes of MOT. Subsequently, this analysis also encompasses nine Korean MOT graduate programs, projecting the seven thematic domains onto their respective curricula. The findings illuminate that within the context of Korean graduate programs, a substantial proportion of the curriculum, amounting to 62.5%, is dedicated to facets encompassing the operational aspects of technology management within corporate contexts, technology management specific to varying industries and technologies, and collaborative endeavors between academia and industry in the form of projects and seminars. Evidently, the Korean approach to technology management education is notably geared towards the cultivation of adept practitioners capable of executing technology management functions at a mid-tier managerial level, aligned with the exigencies of regional industries. Grounded in the analysis of technology management curricula, this study extrapolates implications for the future trajectory of MOT education in Korea, encompassing a consideration of the stages of industrial development. It underscores the necessity to augment the educational curricula pertaining conceptual foundation of technology and innovation, strategic perspectives of technology and innovation, and the socio-economic context of technology management.

Results of Preoperative Concurrent Chemoradiotherapy for the Treatment of Rectal Cancer (직장암의 수술 전 동시적 항암화학방사선치료 결과)

  • Yoon, Mee-Sun;Nam, Taek-Keun;Kim, Hyeong-Rok;Nah, Byung-Sik;Chung, Woong-Ki;Kim, Young-Jin;Ahn, Sung-Ja;Song, Ju-Young;Jeong, Jae-Uk
    • Radiation Oncology Journal
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    • v.26 no.4
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    • pp.247-256
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    • 2008
  • Purpose: The purpose of this study is to evaluate anal sphincter preservation rates, survival rates, and prognostic factors in patients with rectal cancer treated with preoperative chemoradiotherapy. Materials and Methods: One hundred fifty patients with pathologic confirmed rectal cancer and treated by preoperative chemoradiotherapy between January 1999 and June 2007. Of the 150 patients, the 82 who completed the scheduled chemoradiotherapy, received definitive surgery at our hospital, and did not have distant metastasis upon initial diagnosis were enrolled in this study. The radiation dose delivered to the whole pelvis ranged from 41.4 to 46.0 Gy (median 44.0 Gy) using daily fractions of $1.8{\sim}2.0\;Gy$ at 5 days per week and a boost dose to the primary tumor and high risk area up to a total of $43.2{\sim}54\;Gy$ (median 50.4 Gy). Sixty patients (80.5%) received 5-fluorouracil, leucovorin, and cisplatin, while 16 patients (19.5%) were administered 5-fluorouracil and leucovorin every 4 weeks concurrently during radiotherapy. Surgery was performed for 3 to 45 weeks (median 7 weeks) after completion of chemoradiotherapy. Results: The sphincter preservation rates for all patients were 73.2% (60/82). Of the 48 patients whose tumor was located at less than 5 cm away from the anal verge, 31 (64.6%) underwent sphincter-saving surgery. Moreover, of the 34 patients whose tumor was located at greater than or equal to 5 cm away from the anal verge, 29 (85.3%) were able to preserve their anal sphincter. A pathologic complete response was achieved in 14.6% (12/82) of all patients. The downstaging rates were 42.7% (35/82) for the T stage, 75.5% (37/49) for the N stage, and 67.1% (55/82) for the overall stages. The median follow-up period was 38 months (range $11{\sim}107$ months). The overall 5-year survival, disease-free survival, and locoregional control rates were 67.4%, 58.9% and 84.4%, respectively. The 5-year overall survival rates based on the pathologic stage were 100% for stage 0 (n=12), 59.1% for stage I (n=16), 78.6% for stage II (n=30), 36.9% for stage III (n=23), and one patient with pathologic stage IV was alive for 43 months (p=0.02). The 5-year disease-free survival rates were 77.8% for stage 0, 63.6% for stage I, 58.9% for stage II, 51.1% for stage III, and 0% for stage IV (p<0.001). The 5-year locoregional control rates were 88.9% for stage 0, 93.8% for stage I, 91.1% for stage II, 68.2% for stage III, and one patient with pathologic stage IV was alive without local recurrence (p=0.01). The results of a multivariate analysis with age (${\leq}55$ vs. >55), clinical stage (I+II vs. III), radiotherapy to surgery interval (${\leq}6$ weeks vs. >6 weeks), operation type (sphincter preservation vs. no preservation), pathologic T stage, pathologic N stage, pathologic overall stage (0 vs. I+II vs. III+IV), and pathologic response (complete vs. non-CR), only age and pathologic N stage were significant predictors of overall survival, pathologic overall stage for disease-free survival, and pathologic N stage for locoregional control rates, respectively. Recurrence was observed in 25 patients (local recurrence in 10 patients, distant metastasis in 13 patients, and both in 2 patients). Acute hematologic toxicity ($\geq$grade 3) during chemoradiotherapy was observed in 2 patients, while skin toxicity was observed in 1 patient. Complications developing within 60 days after surgery and required admission or surgical intervention, were observed in 11 patients: anastomotic leakage in 5 patients, pelvic abscess in 2 patients, and others in 4 patients. Conclusion: Preoperative chemoradiotherapy was an effective modality to achieve downstaging and sphincter preservation in rectal cancer cases with a relatively low toxicity. Pathologic N stage was a statistically significant prognostic factor for survival and locoregional control and so, more intensified postoperative adjuvant chemotherapy should be considered in these patients.

The Results of Definitive Radiation Therapy and The Analysis of Prognostic Factors for Non-Small Cell Lung Cancer (비소세포성 폐암에서 근치적 방사선치료 성적과 예후인자 분석)

  • Chang, Seung-Hee;Lee, Kyung-Ja;Lee, Soon-Nam
    • Radiation Oncology Journal
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    • v.16 no.4
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    • pp.409-423
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    • 1998
  • Purpose : This retrospective study was tried to evaluate the clinical characteristics of patients, patterns of failure, survival rates, prognostic factors affecting survival, and treatment related toxicities when non-small cell lung cancer patients was treated by definitive radiotherapy alone or combined with chemotherapy. Materials and Methods : We evaluated the treatment results of 70 patients who were treated by definitive radiation therapy for non-small cell lung cancer at the Department of Radiation Oncology, Ewha Womans University Hospital, between March 1982 and April 1996. The number of patients of each stage was 2 in stage I, 6 in stage II, 30 in stage III-A, 29 in stage III-B, 3 in stage IV. Radiation therapy was administered by 6 MV linear accelerator and daily dose was 1.8-2.0 Gy and total radiation dose was ranged from 50.4 Gy to 72.0 Gy with median dose 59.4 Gy. Thirty four patients was treated with combined therapy with neoadjuvant or concurrent chemotherapy and radiotherapy, and most of them were administered with the multi-drug combined chemotherapy including etoposide and cisplatin. The survival rate was calculated with the Kaplan-Meier methods. Results : The overall 1-year, 2-year, and 3-year survival rates were 63$\%$, 29$\%$, and 26$\%$, respectively. The median survival time of all patients was 17 months. The disease-free survival rate for 1-year and 2-year were 23$\%$ and 16$\%$, respectively. The overall 1-year survival rates according to the stage was 100$\%$ for stage I, 80$\%$ for stage II, 61$\%$ for stage III, and 50$\%$ for stage IV. The overall 1-year 2-year, and 3-year survival rates for stage III patients only were 61$\%$, 23$\%$, and 20$\%$, respectively. The median survival time of stage III patients only was 15 months. The complete response rates by radiation therapy was 10$\%$ and partial response rate was 50$\%$. Thirty patients (43$\%$) among 70 patients assessed local control at initial 3 months follow-up duration. Twenty four (80$\%$) of these 30 Patients was possible to evaluate the pattern of failure after achievement of local control. And then, treatment failure occured in 14 patients (58$\%$): local relapse in 6 patients (43$\%$), distant metastasis in 6 patients (43$\%$) and local relapse with distant metastasis in 2 patients (14$\%$). Therefore, 10 patients (23$\%$) were controlled of disease of primary site with or without distant metastases. Twenty three patients (46$\%$) among 50 patients who were possible to follow-up had distant metastasis. The overall 1-year survival rate according to the treatment modalities was 59$\%$ in radiotherapy alone and 66$\%$ in chemoirradiation group. The overall 1-year survival rates for stage III patients only was 51$\%$ in radiotherapy alone and 68$\%$ in chemoirradiation group which was significant different. The significant prognostic factors affecting survival rate were the stage and the achievement of local control for all patients at univariate- analysis. Use of neoadjuvant or concurrent chemotherapy, use of chemotherapy and the achievement of local control for stage III patients only were also prognostic factors. The stage, pretreatment performance status, use of neoadjuvant or concurrent chemotherapy, total radiation dose and the achievement of local control were significant at multivariate analysis. The treatment-related toxicities were esophagitis, radiation pneunonitis, hematologic toxicity and dermatitis, which were spontaneously improved, but 2 patients were died with radiation pneumonitis. Conclusion : The conventional radiation therapy was not sufficient therapy for achievement of long-term survival in locally advanced non-small cell lung cancer. Therefore, aggressive treatment including the addition of appropriate chemotherapeutic drug to decrease distant metastasis and preoperative radiotherapy combined with surgery, hyperfractionation radiotherapy or 3-D conformal radiation therapy for increase local control are needed.

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Study of Animation 3-Dimensional Motion Picture (애니메이션 입체 영화에 대한 연구)

  • Min, Kyung-Mi
    • Cartoon and Animation Studies
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    • s.9
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    • pp.127-142
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    • 2005
  • Not only in Korea but throughout the entire world millions of people are in contact with images. Images have become a medium through which to transmit anything from simple visualizations of moving images to knowledge and information. The age of the internet has arisen thanks to scientific development, and the internet generation's acquisition of information is continuously becoming faster. The spectators, ufo must choose amongst the excessive amount of available information, are changing along with it just as quickly. The method of visual transmission has changed to match the demands of the fast-changing pace of the new generation. In order to receive an instantaneous selection amongst much information, the primary requisite is attracting one's attention, and then presenting a corresponding feeling of satisfaction. The early stages of film arose from the desire to capture one's actual situation as it realty is. Unsatisfied with the still picture, people developed the motion picture. Research has succeeded in reproducing 3-dimensional images more realistic than the actual image we perceive as a result of the difference in visual perspective of both eyes and their response to rays of light From color film to 3-dimensional pictures, people enjoy the magnificent results of this. All fields within the category of film are continuously studying the human desire to pursue their visual side, namely the pursuit of visual images with a maximum sense of reality. The images that millions of people around the world see now are flat. The screen's depth and optical illusions effectively give a sense of reality while conveying information. However, although the flat screen is able to create a sense of depth using the different visual perspective of each eye for the realization of a cubic effect, there are limitations. Entering the 21s1 century, there is a quickly-arising branch within the field of image media which seeks to overcome these limitations Although 3-dimensional images began in films, entering the latter half of the 20th century, due to development of 3-dimensional images using the mediums of the animation field, cellular phones, advertisement screens, television etc., without restriction is designated as 'image.'. With research having started around 1900 and continuing for over 100 years, we are now able to witness the popularization of 3-dimensional films happening before our very eyes. Within our own country, we can frequently see them at amusement parks and museums. In the future, through the popularization of HDTV etc., there is a good outlook for practical use of 3-dimensional images in televisions with advanced picture qualify as well as in other areas. Together with the international current, research on 3-dimensional films has been activated in Korea and is rising as a main current in the film industry. Within this context, the contents and understanding of 3-dimensional images must keep in step with the pace of technical advancements. In order to accelerate of development of film contents to keep in pace with technical developments, this dissertation presents the techniques and technical aspects of future developments, and shows the need to prepare in advance to make the field grow- and thereby avoid having a lack of experts and being conquered by other nations in the field - rather than only advancing the technical aspects and importing the contents. This dissertation aims to stimulate interest and continual research by progressive-thinking people related to the film industry. Part II looks into the definition and types of 3-dimensional motion pictures, the terminology, the fundamentals of image formation, current market fluctuations, and looks into 3-dimensional techniques which can be borrowed and introduced in 3-dimensional animations. Part III concerns 3-dimensional animated films. It analyzes 3-dimensional production techniques while using the introduction of specific animation techniques in the 2004 production Lee Sun Shin and Nelson - Naval Heroes 3-dimensional animation produced in 2004 by Clay & Puppet Stop-Motion Animation & Computer Graphic. Original Korean title: 해전영웅 이순신과 넬슨. as an example, and it also looks into how current film techniques used in animations can be applied in 3-dimensional films. Additionally, the actual stages of the various fields of 3-dimensional animations are presented. Given the current direction and advancement of 3-dimensional films making use of animations and the possible realization of this field, the author plans to weigh the development of this yet unexploited new market Not looking at the current progress of the field, but rather the direction of the hypothetical types of animation techniques, the author predicts the marketability and possibility of development of each area.

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Herbicidal Phytotoxicity under Adverse Environments and Countermeasures (불량환경하(不良環境下)에서의 제초제(除草劑) 약해(藥害)와 경감기술(輕減技術))

  • Kwon, Y.W.;Hwang, H.S.;Kang, B.H.
    • Korean Journal of Weed Science
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    • v.13 no.4
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    • pp.210-233
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    • 1993
  • The herbicide has become indispensable as much as nitrogen fertilizer in Korean agriculture from 1970 onwards. It is estimated that in 1991 more than 40 herbicides were registered for rice crop and treated to an area 1.41 times the rice acreage ; more than 30 herbicides were registered for field crops and treated to 89% of the crop area ; the treatment acreage of 3 non-selective foliar-applied herbicides reached 2,555 thousand hectares. During the last 25 years herbicides have benefited the Korean farmers substantially in labor, cost and time of farming. Any herbicide which causes crop injury in ordinary uses is not allowed to register in most country. Herbicides, however, can cause crop injury more or less when they are misused, abused or used under adverse environments. The herbicide use more than 100% of crop acreage means an increased probability of which herbicides are used wrong or under adverse situation. This is true as evidenced by that about 25% of farmers have experienced the herbicide caused crop injury more than once during last 10 years on authors' nationwide surveys in 1992 and 1993 ; one-half of the injury incidences were with crop yield loss greater than 10%. Crop injury caused by herbicide had not occurred to a serious extent in the 1960s when the herbicides fewer than 5 were used by farmers to the field less than 12% of total acreage. Farmers ascribed about 53% of the herbicidal injury incidences at their fields to their misuses such as overdose, careless or improper application, off-time application or wrong choice of the herbicide, etc. While 47% of the incidences were mainly due to adverse natural conditions. Such misuses can be reduced to a minimum through enhanced education/extension services for right uses and, although undesirable, increased farmers' experiences of phytotoxicity. The most difficult primary problem arises from lack of countermeasures for farmers to cope with various adverse environmental conditions. At present almost all the herbicides have"Do not use!" instructions on label to avoid crop injury under adverse environments. These "Do not use!" situations Include sandy, highly percolating, or infertile soils, cool water gushing paddy, poorly draining paddy, terraced paddy, too wet or dry soils, days of abnormally cool or high air temperature, etc. Meanwhile, the cultivated lands are under poor conditions : the average organic matter content ranges 2.5 to 2.8% in paddy soil and 2.0 to 2.6% in upland soil ; the canon exchange capacity ranges 8 to 12 m.e. ; approximately 43% of paddy and 56% of upland are of sandy to sandy gravel soil ; only 42% of paddy and 16% of upland fields are on flat land. The present situation would mean that about 40 to 50% of soil applied herbicides are used on the field where the label instructs "Do not use!". Yet no positive effort has been made for 25 years long by government or companies to develop countermeasures. It is a really sophisticated social problem. In the 1960s and 1970s a subside program to incoporate hillside red clayish soil into sandy paddy as well as campaign for increased application of compost to the field had been operating. Yet majority of the sandy soils remains sandy and the program and campaign had been stopped. With regard to this sandy soil problem the authors have developed a method of "split application of a herbicide onto sandy soil field". A model case study has been carried out with success and is introduced with key procedure in this paper. Climate is variable in its nature. Among the climatic components sudden fall or rise in temperature is hardly avoidable for a crop plant. Our spring air temperature fluctuates so much ; for example, the daily mean air temperature of Inchon city varied from 6.31 to $16.81^{\circ}C$ on April 20, early seeding time of crops, within${\times}$2Sd range of 30 year records. Seeding early in season means an increased liability to phytotoxicity, and this will be more evident in direct water-seeding of rice. About 20% of farmers depend on the cold underground-water pumped for rice irrigation. If the well is deep over 70m, the fresh water may be about $10^{\circ}C$ cold. The water should be warmed to about $20^{\circ}C$ before irrigation. This is not so practiced well by farmers. In addition to the forementioned adverse conditions there exist many other aspects to be amended. Among them the worst for liquid spray type herbicides is almost total lacking in proper knowledge of nozzle types and concern with even spray by the administrative, rural extension officers, company and farmers. Even not available in the market are the nozzles and sprayers appropriate for herbicides spray. Most people perceive all the pesticide sprayers same and concern much with the speed and easiness of spray, not with correct spray. There exist many points to be improved to minimize herbicidal phytotoxicity in Korea and many ways to achieve the goal. First of all it is suggested that 1) the present evaluation of a new herbicide at standard and double doses in registration trials is to be an evaluation for standard, double and triple doses to exploit the response slope in making decision for approval and recommendation of different dose for different situation on label, 2) the government is to recognize the facts and nature of the present problem to correct the present misperceptions and to develop an appropriate national program for improvement of soil conditions, spray equipment, extention manpower and services, 3) the researchers are to enhance researches on the countermeasures and 4) the herbicide makers/dealers are to correct their misperceptions and policy for sales, to develop database on the detailed use conditions of consumer one by one and to serve the consumers with direct counsel based on the database.

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