• Journal of Biomedical Engineering Research
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• v.23 no.2
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• pp.147-153
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• 2002

The purpose of this study was to evacuate the effect of different types of Poly(lactic-co-glycolic acid) (PLGA) scaffolds on the formation of human auricular and septal cartilages. All of the scaffolds were formed in a tubular shape for potential application for artificial trachea or esophagus with either 110,000 g/mol PLGA. 220,000 g/mol PLGA. or a combination of both. In order to maintain the tubular shape in vivo, two methods were used. One method was inserting polyethylene tube at the center of scaffolds made of 110,000 g/mol PLGA. The other method involved combination of the two different molecular weight PLGA's. The inner surface of tubular shaped scaffold made with 110,000 g/mol PLGA was coated with 220,000 9/mol PLGA to give more mechanical rigidity. Elastic cartilage was taken from the ear of a patient aged under 20 nears old and hyaline cartilage was taken from the nasal septum. The chondrocytes were then isolated. After second passage, the chondrocytes were seeded on the PLGA scaffolds followed by in vitro culture for one week. The cells-PLGA scaffold complex were implanted subcutaneously on the back of nude mice for 8 weeks. The tissue engineered cartilages were separated from nude mice and examined histologically after staining with the Hematoxylin Eosin. The morphology of the scaffolds were examined by scanning electron microscopy. The pores were well formed and uniformly distributed in the various PLGA scaffolds. After 8 weeks in vivo culture, cartilage was well formed with 110,000 g/mol PLGA. however lumen had collapsed. In contrast. a minimal amount of neocartilage was formed with 220,000 g/mol PLGA, while the architecture of scaffold and lumen were well preserved. Elastic cartilage formed more neocartilage than hyaline. Hyaline and elastic neocartilage were well formed on 110,000 g/mol PLGA with the polyethylene tube, exhibiting mature chondrocytes and preservation of the tubular shape. It was found that 110,000 g/mol PLGA was more appropriate for cartilage formation but higher molecular weight polymer was necessary to maintain the three dimensional shape of the scaffold.

• Cartoon and Animation Studies
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• s.32
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• pp.189-220
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• 2013

It is expected that interests and supports for 'the creative economy' will increase considerably since the establishment of the Park Geun Hye Administration. According to a report with respect to its cultural policy handed in by the Minister of Culture to the president on March 28, 2013, the administration will set up a basic plan of establishing regional fusion-typed laboratories including such genres as story telling, animations, games, cartoons, performances, etc. in May this year, and opening contents Korea laboratories across the country by the first quarter in 2014 as part of its core task. Furthermore, it will focus on implementing such policies for training professional manpower as creative mentoring programs, expansion of education for field employees and expansion of a creative education for young students, including a plan to train 1,000 creative contents talents by 2017 as described in the report. Since the Comics Promotional Law took effect in August 2012, the Korea Culture and Content Agency and the Comics Industry have been establishing the third plan for medium and long term development of the comics industry together. One of the most important policy is about training professional manpower. "Joint Business with Creative Talents," in which the amount of 4.5 billion won was invested, has already been implemented, and "Support Business for Field Employees of Comics Creating Enterprises," in which the amount of 0.6 billion won was invested, has been performed so far through the Korea Comics Contents Agency upon the request of the Comics Industry. The government's plan to train professional manpower is interlocked with its foundation and employment policies, and thus, this will be a good opportunity for colleges and universities that have comics related majors, especially for those that need proper measures for bring their graduates a chance to get a job. Accordingly, it seems that if the government develops more aggressive policies, reflects this on the third medium and long term development plan of the comics industry, and then organizes policy and study meetings led by the learned societies to implement this, it will be able to generate a significant synergy effect. This Article will concentrate on first examining the flow and patterns of the policy to train special manpower by the comics industry, the Ministry of Culture and related institutions since the establishment of the Comics Promotional Law, analyzing some problems in the first and second medium and long term development plan of the comics industry to be implemented from 2003 through 2013 and the third medium and long term development plan to be announced in June 2013 to train professional manpower, and then suggesting an effective direction and some alternatives to train professional manpower in universities in a medium and long term way.

• Proceedings of the Korean Statistical Society Conference
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• 2005.11a
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• pp.117-120
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• 2005

인구주택총조사는 국가통계의 가장 기본이 되는 자료를 생산하는 조사로 거의 대부분의 나라에서 전수조사방식으로 정기적으로 시행해왔다. 그러나 최근 들어 일부 국가, 특히 선진국에서 응답거부가 늘고, 조사대상을 접촉하기 어려운 등 조사환경이 나빠지고 있다. 아울러 조사비용이 급격하게 증가하고 있다. 이에 각 국의 통계청에서는 이러한 상황을 인구센서스에 대한 '근본적인 도전'으로 간주하고 있다(Jensen, 2000). 심지어 독일이나 네델란드에서는 조사환경의 악화로 1990년대 이후 인구센서스를 중단한 상태이다(Bierau, 2000). 조사환경의 악화는 조사의 포괄성과 신뢰성에 대한 문제를 야기한다. 선진국들과 마찬가지로 우리나라에서도 조사환경이 빠른 속도로 악화되고 있다. 더욱이 우리의 경우 읍면동사무소 기능축소로 말미암아 과거 인구주택총조사에서 실제 조사에 도움을 주었던 행정지원이 없어짐에 따라 앞으로 조사의 어려움은 더욱 커질 것으로 보인다. 이렇듯 악화되는 조사환경변화에 대응하여 선진 국가에서는 다양한 형태의 인구센서스방식들이 모색되고 있다. 많은 나라들이 순환형 센서스보다는 행정자료를 인구주택총조사에 활용하는 방안을 모색하고 있으며, 덴마크나 핀란드 등 일부 국가에서는 이미 전혀 조사를 하지 않고 행정자료로 대부분의 인구센서스 통계를 생산하고 있다(Harala, 1996; Gaasemyr, 1999; Laihonen, 1999), 많은 나라들이 행정자료를 활용한 인구센서스 방식을 선호하는 데는 또 다른 이유가 있다. 자료의 측면에서 보면, 행정자료를 활용할 경우 매년 인구센서스 통계를 생산할 수 있다. 실제로 현재 덴마크와 핀란드는 인구센서스에 준하는 통계를 매년 생산하고 있다. 또한 이러한 자료를 바탕으로 지역통계 수요에 즉각 대처할 수 있다. 더 나아가 이와 같은 통계는 전 국민에 대한 패널자료이기 때문에 통계적 활용의 범위가 방대하다. 특히 개인, 가구, 사업체 등 사회 활동의 주체들이 어떻게 변화하는지를 추적할 수 있는 자료를 생산함으로써 다양한 인과적 통계분석을 할 수 있다. 행정자료를 활용한 인구센서스의 이러한 특징은 국가의 교육정책, 노동정책, 복지정책 등 다양한 정책을 정확한 자료를 근거로 수립할 수 있는 기반을 제공한다(Gaasemyr, 1999). 이와 더불어 행정자료 기반의 인구센서스는 비용이 적게 드는 장점이 있다. 예를 들어 덴마크나 핀란드에서는 조사로 자료를 생산하던 때의 1/20 정도 비용으로 행정자료로 인구센서스의 모든 자료를 생산하고 있다. 특히, 최근 모든 행정자료들이 정보통신기술에 의해 데이터베이스 형태로 바뀌고, 인터넷을 근간으로 한 컴퓨터네트워크가 발달함에 따라 각 부처별로 행정을 위해 축적한 자료를 정보통신기술로 연계${cdot}$통합하면 막대한 조사비용을 들이지 않더라도 인구센서스자료를 적은 비용으로 생산할 수 있는 근간이 마련되었다. 이렇듯 행정자료 기반의 인구센서스가 많은 장점을 가졌지만, 그렇다고 모든 국가가 당장 행정자료로 인구센서스를 대체할 수 있는 것은 아니다. 행정자료로 인구센서스통계를 생산하기 위해서는 각 행정부서별로 사용하는 행정자료들을 연계${cdot}$통합할 수 있도록 국가사회전반에 걸쳐 행정 체제가 갖추어져야 하기 때문이다. 특히 모든 국민 개개인에 관한 기본정보, 개인들이 거주하며 생활하는 단위인 개별 주거단위에 관한 정보가 행정부에 등록되어 있고, 잘 정비되어 있어야 하며, 정보의 형태 또한 서로 연계가 가능하도록 표준화되어있어야 한다. 이와 더불어, 현재 인구센서스에서 표본조사를 통해 부가적으로 생산하는 경제활동통계를 생산하기 위해서는 개인이 속한 사업체를 파악할 수 있도록 모든 사업체가 등록되어 있고, 개인의 경제활동과 관련된 각종 정보들이 사업체에 잘 기록 및 정비되어 있어야 한다. 따라서 행정자료 기반의 인구센서스통계생산은 단지 국가의 통계뿐만 아니라 행정조직과 행정체계를 정비하고, 개인과 사업체의 등록체계를 정비하며, 사업체의 개인에 관한 정보를 정비하여 표준화하는 막대한 작업을 수반한다. 이런 이유에서 대부분의 국가들은 장래에 행정자료 기반의 인구센서스통계생산을 목표로 하되, 당장은 행정자료를 인구센서스에 보조적 수단을 사용하는 데 노력을 기울이고 있다. 우리나라의 경우 행정자료를 인구주택총조사에 활용할 수 있는 몇 가지 중요한 기반을 갖추고 있다. 첫째, 1962년부터 시행한 주민등록제도가 있다. 주민등록제도는 모든 국민 개개인을 파악할 수 있는 주민등록번호를 갖추고 있으며 40년 이상 제도화되어 오류가 거의 없는 편이다. 둘째, 세계 10위권 내에 들 정도로 높은 우리나라의 정보화 수준과 2000년부터 시작된 전자정부사업으로 행정자료를 연계${cdot}$통합할 수 있는 기반이 잘 갖추어져 있다. 반면, 우리나라 행정자료 가운데 주거(생활)단위와 사업체를 파악할 수 있는 자료는 매우불완전하다. 대표적으로 인구센서스통계의 주요한 단위인 가구를 파악할 수 있는 수준으로 주소체계가 정비되어 있지 않으며, 많은 사업체, 특히 소규모 사업 가운데 등록되어 있지 않거나 등록오류가 많은 편이다. 이외에도 과세대장, 토지대장 등 많은 행정자료가 아직은 불완전하여 이들을 직접 연계하기에 어렵다. 행정자료를 연계하기 위해서는 모든 자료를 정비하고 표준화하여 실제 행정에 활용하여야 하기 때문에 행정적으로 많은 노력과 시간이필요하다. 따라서 현재는 손쉬운 부분에서부터 인구주택총조사에 행정자료를 활용하고, 앞으로 활용 과정을 거치면서 행정자료를 정비하고 표준화하는 장기적인 방안을 마련할 필요가 있다.

• Radiation Oncology Journal
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• v.12 no.1
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• pp.73-80
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• 1994

From December 1989 to February 1993, 108 patients with Non-Small Cell Lung Cancers(NSCLC) were studied retrospectively to evaluate radiotherapeutic significance of serum levels of NSE. We considered elevated serum neuron specific enolase(S-NSE) level as one of the neuroendocrine features in NSCLC. Histopathologic evaluation revealed 86 squamous cell carcinomas, 11 adenocarcinomas.3 large cell carcinomas, 3 mucoepidermoid carcinomas, and 5 unknown pathology. Eight Patients had stage 1,40 stage IlIA, and 60 stage lIIB.S-NSE level greater than 15 ng/ml was considered as elevated, and below this considered as normal. All patients recieved radiotherapy as primary treatment modality. The responders to radiotherapy had significantly higher mean S-NSE level than non-responders (28.5 ng/ml vs 20 ng/ml, p=0.01). Overall 2-year survival rate(YSR) was 23.6$ \% $. According to radiotherapy response, 2 YSR for Patients with CR, PR, and NR were 39.2$ \% $, 28.6$ \% $, and 6.2$ \% $ respectively(p=0.001). 2 YSR for patients with elevated and normal S-NSE were 14.6$ \% $ and 31.7$ \% $(p=0.02). The patients with NR showed no difference in survival according to S-NSE level. When we considered all patients, S-NSE level showed no significant impact on response. But for squamous cell carcinomas alone, patients with elevated S-NSE had more responders(80$ \% $ vs 61$ \% $, p=0.05). There was no correlation between tumor characteristics and S-NSE level. But the patients with elevated S-NSE had more patients with higher nodal stage, Based on our and other datas, NSCLC with neuroendocrine features have different response to treatment and clinical behavior compared to other NSCLC. Thus, this subgroup may need different treatment modality, and S-NSE level may have prognostic significance.

• Radiation Oncology Journal
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• v.18 no.1
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• pp.67-72
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• 2000

Background :The authors have developed a Digital image chart(DIC) and digital Radiotherapy Record System (DRRS). We have evaluated the DIC and DRRS for reliability, usefulness, ease of use, and efficiency. Materials and Methods :The basic design of the DIC and DRRS was to build an digital image database of radiation therapy Patient records for a more efficient and timely flow of critical image information throughout the department. This system is a submit of comprehensive radiation oncology management system (C-ROMS) and composed of a picture archiving and communication system (PACS), a radiotherapy information database, and a radiotherapy imaging database. The DIC and DRRS were programmed using Delphi under a Windows 95 environment and is capable of displaying the digital images of patients identification photos, simulation films, radiotherapy setup, diagnostic radiology images, gross lesion Photos, and radiotherapy Planning isodose charts with beam arrangements. Twenty-three clients in the department are connected by Ethernet (10 Mbps) to the central image server (Sun Ultra-sparc 1 workstation). Results :From the introduction of this system in February 1998 through December 1999, we have accumulated a total of 15,732 individual images for 2,556 patients. We can organize radiation therapy in a 'paperless' environment in 120 patients with breast cancer. Using this system, we have succeeded in the prompt, accurate, and simultaneous access to patient care information from multiple locations throughout the department. This coordination has resulted in improved operational efficiency within the department. Conclusion :The authors believe that the DIC and DRRS has contributed to the improvement of radiation oncology department efficacy as well as to time and resource savings by providing necessary visual information throughout the department conveniently and simultaneously. As a result, we can also achieve the 'paperless' and 'filmless' practice of radiation oncology with this system.

• Korean Journal of Soil Science and Fertilizer
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• v.7 no.3
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• pp.163-175
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• 1974

Effects on yields, yield components and nutrient content of potassium depression for two or three weeks at various growth stages were investigated in rice (var. Jinheung) under sand culture system.(K 40 ppm 1973) 1. Analysis of variance showed significant difference among treatments of both two-week (at p=0.01) and three-week depression (at p=0.05) in yield. 2. Most sensitive stage to potassium depression on yield appeared two weeks until heading (42% yield decrease) and sensitivity decreased the growth stage is apart from heading either before or after. During 30 days after transplanting two-week potassium depression increased yield, but three-week depression decreased yield. Until about 30 days after heading depression caused poor yield. 3. Root potassium involves in harvest index, filled grain ratio and grain weight with significant correlation and considerably in spikelet per panicle while potassium in leaf sheath+culm involves considerably in spikelet per panicle and panicle per hill. Relative total dry matter weight was significantly correlated with panicle per hill, spikelet per panicle and K or K/Ca+Mg only in leaf sheath+culm. The indications are that root potassium contributes for building sink and efficiency of structure while potassium in leaf sheat+culm primarily for building source, productive structure. 4. Relative yield was significantly correlated with potassium content in root and leaf sheath+culm and with K/Ca+Mg and its ratio before and after depression in root indicating that potassium depression occurs greatly in root and that K/Ca+Mg might have more important role than K content alone under depression. 5. Optimum level of $K_2O$ appears around 3% in leaf blade. 4% in leaf sheath+culm and 1% in root under the assumption that below these level the same content has the same role in relation to yield during growth. The K/Ca+Mg appeares to be 2.5 in root and should not decrease throughout the growth stages. 6. The increase of sodium content in plant by K depression was highest, especially in leaf sheath during the most insensitive period to K depression suggesting that insensitivity may be attributed to partial replacement of Na for K. Partial replacement seems very little in sensitive stage (later stage) and sensitive organ (root).

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.18 no.2
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• pp.137-146
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• 2006

This is the second of a two-part paper which describes comparison of reliability design methods by application to Donghae Harbor Breakwaters. In this paper, Part 2, we deal with sliding of caissons. The failure modes of a vertical breakwater, which consists of a caisson mounted on a rubble mound, include the sliding and overturning of the caisson and the failure of the rubble mound or subsoil, among which most frequently occurs the sliding of the caisson. The traditional deterministic design method for sliding failure of a caisson uses the concept of a safety factor that the resistance should be greater than the load by a certain factor (e.g. 1.2). However, the safety of a structure cannot be quantitatively evaluated by the concept of a safety factor. On the other hand, the reliability design method, for which active research is being performed recently, enables one to quantitatively evaluate the safety of a structure by calculating the probability of failure of the structure. The reliability design method is classified into three categories depending on the level of probabilistic concepts being employed, i.e., Level 1, 2, and 3. In this study, we apply the reliability design methods to the sliding of the caisson of the breakwaters of Donghae Harbor, which was constructed by traditional deterministic design methods to be damaged in 1987. Analyses are made for the breakwaters before the damage and after reinforcement. The probability of failure before the damage is much higher than the allowable value, indicating that the breakwater was under-designed. The probability of failure after reinforcement, however, is close to the allowable value, indicating that the breakwater is no longer in danger. On the other hand, the results of the different reliability design methods are in fairly good agreement, confirming that there is not much difference among different methods.

• Applied Chemistry for Engineering
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• v.27 no.6
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• pp.583-589
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• 2016

Lubricant additives including zinc dialkyldithiophosphate (ZDDP) containing metal have been widely used due to the advantage of very low cost, but they can generate impurities such as ash. In this work, ZDDP containing metals was partially replaced with bis[3-(dialkyloxyphosphorothionyl) thio-2-methylpropanyloxy] butane (BAP4s) which was synthesized conveniently and effectively from alkanediol without any metal components. Also, the wear resistance property of synthesized BAP4s were studied. Wear scar diameter (WSD) values of BAP4s with butyl, octyl, decyl, dodecyl or tetradecyl groups were also measured by four-ball test. As the length of the alkyl group increased from 4 to 8, the WSD value of BAP4s decreased rapidly from 0.59 to 0.45 mm, but from 8 to 14, the value increased very slowly from 0.45 to 0.50 mm. Thus, among all BAP4s, B8P4 having BAP4 with the octyl group, showed the lowest WSD value. Furthermore, the WSD values were measured in a lubricant base oil mixed with a 0.50 percent concentration (w/w) of either BAP4 or ZDDP. The former was 0.55 mm, and the latter was 0.45 mm. The thermal stability and tribofilm formation peroperty were also measured by thermogravimetric analyzer (TGA) and energy-dispersive X-rays spectroscopy (EDS), respectively.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.37 no.2
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• pp.185-197
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• 1992

Differences in the amount and chemical characteristics of the epicuticular waxes on rice leaves were studied for the active tillering and heading stages of rice varieties differing widely in gross leaf-surface property and genetics. The amount of waxes on surfaces of rice leaf-blades was determined by extraction with chloroform and chemical composition of the waxes was characterized by thin layer chromatography, gas liquid chromatography and infrared spectrophotometry. The amount of waxes varied by variety and significantly with growth stage. The amount at the heading stage was 1.7 to 3.6 mg/g fresh weight of leaves, which was two to three times as much as that at the tillering stage of 0.8 to 1.8 mg/g fresh weight. The waxes consisted of seven chemical classes, namely diols, fatty acids, fatty alcohols, fatty aldehydes, fatty esters, saturated and unsaturated hydrocarbons. Diols and unsaturated hydrocarbons were identified as new chemical classes of the rice epicuticular waxes. The polar constituents such as dials, fatty acids and fatty alcohols and the non-polars such as fatty aldehydes, fatty esters, and saturated and unsaturated hydrocarbons were identified at the heading stage, but at the tillering stage only the non-polar compounds were identified. In the carbon numbers (C) of the chemical classes, diols were composed entirely of C30 and acids were mainly of C30 and C31. In alcohols, primary alcohols were composed of C13 and C32, and the secondary alcohols were of C14, C16 and / or C30 regardless of the rice varieties. The acid portion of fatty esters, mainly composed of C22 and C23, showed low cabon numbers compared with the aldehydes. The alcohol portion of them showed a wide distribution in carbon numbers from C13 to C26 depending on the rice varieties. Hydrocarbons had odd carbon numbers, consisting mainly of C29 and C31.

• Journal of Food Hygiene and Safety
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• v.33 no.3
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• pp.168-175
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• 2018

The use of microwave-assisted extraction and an acid-base clean-up process to determine the amount of methylmercury (MeHg) in marine products was suggested in order to improve the complicated sample preparation process. The optimal conditions for microwave-assisted extraction was developed by using a 10% NaCl solution as an extraction solution, setting the extraction temperature at $50^{\circ}C$, and holding for 15 minutes to extract the MeHg in marine products. A NaOH solution was selected as a clean-up substitute instead of L-cysteine solution. Overall, 670 samples of marine products were analyzed for total mercury (Hg). Detection levels were in the range of $0.0006{\sim}0.3801{\mu}g/kg$. MeHg was analyzed and compared using the current food code and the proposed method for 49 samples which contained above 0.1 mg/kg of Hg. Detection ranges of methylmercury followed by the Korea Food Code and the proposed method were $75.25(ND{\sim}516.93){\mu}g/kg$ and $142.07(100.14{\sim}244.55){\mu}g/kg$, respectively. The total analytical time of proposed method was reduced by more than 25% compared with the current food code method.