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Narrative Inquiry : Practical experience of an Introduction to Engineering (공학입문 교과 실행경험에 관한 내러티브 탐구)

  • Park, Kyung-Moon;Kim, Taehoon
    • 대한공업교육학회지
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    • v.34 no.2
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    • pp.128-160
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    • 2009
  • Narratively I have described interactions between two teachers performing an introduction to the engineering class with various situations such as place, teacher, student and subject. I have specifically illuminated a three-dimensional narrative inquiry space embracing the culture of the university, the college of engineering and the ABEEK(Accreditation Board of Engineering Education of Korea)program. The result of the study is as follows: First, in order to stimulate the students' motivation, the teachers have to make not only their class PowerPoint slides match the size of the classroom, but the content of the slides must be condensed with core concepts. They also should utilized some video clips to empower students' interest in the subject within their classrooms. Second, the teachers should do various class activities in the classroom. Instead of spending most of the class time with his/her explanation, it would be advantageous for the teachers to allow the students to perform a task in class. Third, the teachers should ask their students about assignments which are helping students' understanding of the subject and planning of their future. Lastly, the teachers need to design the mid-term and the final tests inducing the students' motivation. Those tests also must test students' creativity and insight of the subject. Thus, the test should consist of an interpretive exercise and an essay type of item thus reducing the multiple choice types of items. There are several limitations to the study. First it is difficult to generalize what we found here because it is a case study. Second, we could not study in depth the effect of the interaction between the two teachers who were performing the introduction to the engineering course during the academic semester. Third, this study just probed into the difficulties of teaching the course. Hence, we have to understand more by focusing on each issue such as adapting to a new learning environment as a student from abroad, a practical experience boosting the students' interest in the introduction to the engineering course, also a practical experience on process based learning-versus result based learning, and an effective management of the student team presentation etc.

Excellent Local Tumor Response after Fractionated Stereotactic Radiation Therapy for Locally Recurrent Nasopharynx Cancer (국소 재발 비인강암에 대한 정위적 방사선 분할 치료의 적용)

  • Lim Do Hoon;Chio Dong Rak;Kim Moon Kyung;Kim Dae Yong;Huh Seung Jae;Baek Chung-Hwan;Chu Kwang Chol;Yoon Sung Soo;Park Keunchil;Ahn Yong-Chan
    • Radiation Oncology Journal
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    • v.15 no.1
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    • pp.19-26
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    • 1997
  • Purpose : This study is to report experience with Fractionated Stereotactic Radiation Therapy (FSRT) for locally recurrent nasopharynx cancer after curative conventional radiation therapy. Materials and Methods : Three Patients with locally recurrent and symptomatic nasopharynx cancer were given FSRT as reirradiation method between the Period of September of 1995 and August of 1996 For two Patients, application of FSRT is their third radiation therapy directed to the nasopharynx. Two patients were given low dose chemotherapy as radiation sensitizer concurrently with FSRT Authors used 3-dimensional coordinate system by individually made, relocatable Gill-Thomas-Cosman (GTC) stereotactic frame and multiple non-coplanar arc therapy dose Planning was done using Xknife-3. Total of 45 Gy/18 fractions or 50 Gy/20 fractions were given. Results : Authors observed satisfactory symptomatic improvement and remarkable objective tumor size decrease by follow-up MR images taken 1 month Post-FSRT in ali three patients, while no neurologic side effect attributable to reirradiation was noticed. Two died at 7 and 9 months with loco-regional and distant seeding outside FSRT field, while one patient is living for 4 month. Conclusion Authors experienced satisfactory therapeutic effectiveness and safety of FSRT as reirradiatlon method for locally recurrent nasopharynx cancer Development of more effective systemic chemotherapeutic regimen is desired for distant metastasis

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Postoperative Pulmonary Vein Stenosis (PVS) in Patients with TAPVR (전 폐정맥 환류 이상의 수술 후 폐정맥 협착에 대한 분석)

  • Jung Sung-Ho;Park Jeong-Jun;Yun Tae-Jin;Jhang Won-Kyoung;Kim Young-Hwue;Ko Jae-Kon;Park In-Sook;Seo Dong-Man
    • Journal of Chest Surgery
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    • v.39 no.5 s.262
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    • pp.347-353
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    • 2006
  • Background: Despite recent advances in surgical technique and perioperative care of total anomalous pulmonary venous return (TAPVR), post-repair pulmonary vein stenosis (PVS) remains as a serious complication. We thought that the most important factors of TAPVR repair to prevent PVS were good exposure, proper alignment, and sufficient stoma size. We analyzed our experience retrospectively. Material and Method: Between Jan. 1995 and Feb. 2005, we studied 74 patients diagnosed with TAPVR suitable for biventricular repair. Supra-cardiac type (n=41, 55.4%) was the most common. Mean CPB time, ACC time, and TCA (40.5%, 30/74) time were $92.1{\pm}25.9\;min,\;39.1{\pm}10.6\;min$, and $30.2{\pm}10.7\;min$, respectively. Mean follow-up duration was $41.4{\pm}29.1$ months and follow-up was possible in all patients. Result: The median age and body weight at operation were 28.5 days ($0{\sim}478$ days) and 3.4 kg $(1.4{\sim}9\;kg)$. Early mortality was 4.1% (3/74). Causes of death were pulmonary hypertensive crisis, sepsis, and sudden death. There was PR-PVS in 2 patients (early: 1, late: 1). Both patients were cardiac type TAPVR drained to coronary sinus. Re-operations were done but only one patient survived. Cumulative survival rate in 5 year and percent freedom from PVS were $94.5{\pm}2.7%\;and\;97.2{\pm}2.0%$, respectively. Conclusion: There was no PVS in patients who underwent extra-cardiac anatomosis between LA and CPVC. Therefore it could be said that our principle might be effective in preventing PR-PVS in patients suitable two-ventricle.

Consumer Motivation for Brand-Switching According to Types of Fashion Products (패션제품 유형에 따른 소비자 상표전환동기 차이)

  • Lim, Eun-Jin;Hwang, Choon-Sup
    • Journal of the Korean Society of Clothing and Textiles
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    • v.33 no.12
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    • pp.1991-2001
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    • 2009
  • This study provides basic information that is needed to build marketing strategies related to consumer brand-switching, through the investigation of consumer motivations for brand-switching, as determined by the types of fashion products. The study was implemented by a descriptive survey method using a questionnaire. The survey was conducted during the period of May $11^{th}$ through July $5^{th}$ 2008. A total of 184 completed responses were analyzed. All respondents were from the Seoul area and between the ages of 20 and 31. Factor analysis and Cronbach's alpha coefficients, one-way ANOVA and Duncan test were employed for the analysis of data. Significant differences were found in brand-switching motives according to the types of fashion products. For clothing, shift behavior occurred more often in conjunction with the attributes of the products itself, such as design, color, price, size, and fiber content. In general, clothes more than shoes, were likely subject to brand-switching most often on the basis of situational factors. On the other hand, for shoes, more brand-switching activities occurred because of non-product attributes, such as discounts, coupons, desire for a change, and wearing of friends. In light of the results, there is a need to differentiate brand related marketing strategies with respect to clothing and shoes. For clothing, efforts focusing on the improvement of the product attributes will be more effective in minimizing brand-switching. There is also a need to improve instructions for increasing the product understanding of salespersons as well as the ability to give advice in accordance with personal consumer characteristics. With regard to shoes, greater efforts should be given to promotional activities, and the desire of consumers for a change in order to prevent brand-switching of customers.

A Study on the Characteristics of Condensable Fine Particles in Flue Gas (배출가스 중 응축성미세먼지 특성 연구)

  • Gong, Buju;Kim, Jonghyeon;Kim, Hyeri;Lee, Sangbo;Kim, Hyungchun;Jo, Jeonghwa;Kim, Jeonghun;Gang, Daeil;Park, Jeong Min;Hong, Jihyung
    • Journal of Korean Society for Atmospheric Environment
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    • v.32 no.5
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    • pp.501-512
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    • 2016
  • The study evaluated methods to measure condensable fine particles in flue gases and measured particulate matter by fuel and material to get precise concentrations and quantities. As a result of the method evaluation, it is required to improve test methods for measuring Condensable Particulate Matter (CPM) emitted after the conventional Filterable Particulate Matter (FPM) measurement process. Relative Standard Deviation (RSD) based on the evaluated analysis process showed that RSD percentages of FPM and CPM were around 27.0~139.5%. As errors in the process of CPM measurement and analysis can be caused while separating and dehydrating organic and inorganic materials from condensed liquid samples, transporting samples, and titrating ammonium hydroxide in the sample, it is required to comply with the exact test procedures. As for characteristics of FPM and CPM concentrations, CPM had about 1.6~63 times higher concentrations than FPM, and CPM caused huge increase in PM mass concentrations. Also, emission concentrations and quantities varied according to the characteristics of each fuel, the size of emitting facilities, operational conditions of emitters, etc. PM in the flue gases mostly consisted of CPM (61~99%), and the result of organic/inorganic component analysis revealed that organic dusts accounted for 30~88%. High-efficiency prevention facilities also had high concentrations of CPM due to large amounts of $NO_x$, and the more fuels, the more inorganic dusts. As a result of comparison between emission coefficients by fuel and the EPA AP-42, FPM had lower result values compared to that in the US materials, and CPM had higher values than FPM. For the emission coefficients of the total PM (FPM+CPM) by industry, that of thermal power stations (bituminous coal) was 71.64 g/ton, and cement manufacturing facility (blended fuels) 18.90 g/ton. In order to estimate emission quantities and coefficients proper to the circumstances of air pollutant-emitting facilities in Korea, measurement data need to be calculated in stages by facility condition according to the CPM measurement method in the study. About 80% of PM in flue gases are CPM, and a half of which are organic dusts that are mostly unknown yet. For effective management and control of PM in flue gases, it is necessary to identify the current conditions through quantitative and qualitative analysis of harmful organic substances, and have more interest in and conduct studies on unknown materials' measurements and behaviors.

Capping Treatment for the Reduction of Phosphorus Release from Contaminated Sediments of Lakes (호소퇴적물로부터 인 용출 저감을 위한 Capping 처리)

  • Kim, Seog-Ku;Lee, Mi-Kyung;Ahn, Jae-Hwan;Yun, Sang-Leen;Kim, So-Jung
    • Journal of Korean Society of Environmental Engineers
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    • v.28 no.4
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    • pp.438-446
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    • 2006
  • A lab-scale batch test was conducted to develop capping materials to reduce the sediment phosphorus in the stagnant water zone of Gyeongancheon in Paldang Lake. The mean grain size(Mz) of sediment in the investigated area was 7.7 ${\phi}$, which is very fine, and the contents of organic carbon($C_{org}$) was 2.4%, which is very high. For the phosphorous release experiment to select the optimal capping material, sand layer, powder-gypsum($CaSO_4{\cdot}2H_2O$), granule-gypsum, complex layer(gypsum+sand) and the control were compared and evaluated in the 150 L reactor for 45 days. In case of the capping with the sand, it was found that the phosphorous from the sediment could be reduced by around 50%. However, it was found that this caused the reduction of the dissolved oxygen in the water column(by less than 3 mg/L) due to the resuspension of sediment and the organic matter decomposition that comes from the generation of $CH_4$ gas in the 1 cm of the sand layer. Therefore, it is likely that the sand layer has to be thickener in case of the sand capping. Powder-gypsum and granule-Gypsum reduced phosphorous release by more than 80%. However, the concentration of ${SO_4}^{2-}$ in the water column increased, making it difficult to apply it to the drinking water protection zone. We developed Fe-Gypsum and $SiO_2$-gypsum materials to reduce the solubility of ${SO_4}^{2-}$. Powder-Gypsum creates the interception film that does not have any aperture on the sediment layer when it is combined with the water. However phosphorous release caused by the generation of $CH_4$ gas may happen at a time when the gypsum layer has the crack. Capping through the complex layer(granule-Gypsum+sand(1 cm)) found to be suitable for the drinking water protection zone because it was effective to prevent phosphorus release. Moreover, this leads to the lower solubility from the concentration of ${SO_4}^{2-}$ into the water column than the powder-Gypsum and granule-Gypsum. The addition of gypsum($CaSO_4{\cdot}2H_2O$) into the sediment can reduce the progress of methanogensis because fast early diagenesis and sufficient supply of ${SO_4}^{2-}$ to the sediment, stimulate the SRB(sulfate reducing bacteria) highly.

Topic Continuity in Korea Narrative (한국 설화문에서의 화제표현의 연속성)

  • Hi-JaChong
    • Korean Journal of Cognitive Science
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    • v.2 no.2
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    • pp.405-428
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    • 1990
  • Language has a social function to communicate information. Linguists have gradually paid their attention to the function of language since the nineteen sixties, especially to the relationship of form, meaning and the function. The relationship could be more clearly grasped through disciyrse-based analysis than through sentence-based analysis. Many researches were centered on the discourse functional notion of topic. In the early 1970's the subject was defined as the grammatiocalized topic the topic as a discrete single constituent of the clause. In the late 1970's several lingusts including Givon suggerted that the topic was not an atomic, disctete entity, and that the clause could have more than one topic. The purpose of the present study is, following Givon, to study grammatical coding devices of topic and to measure the relative topic continuity/discontinuity of participant argu, ents in Korean narratives. By so doing, I would like to shed some light on effective ways of communicating information. The grammatical coding devices analyzed are the following eight structures: zero-anaphora, personal pronous, demonstrative pronouns, names, noun phrases following demonstratives, noun phrases following possessives, definite noun phrases and indefinite referentials. The narrative studied for the count was taken from the KoreanCIA chief's Testiomny:Revolution and Idol by Hyung Wook Kim. It was chosen because it was assumed that Kim's purpose in the novel was to tell a true story, which would not distort the natural use of language for literary effect. The measures taken in the analysis wre those of 'lookback', 'persistence', ambiguity'. The first of these, 'lookback', is a measure of the size of gap between the previous occurrence of a referent and its current occurence in the clause. The meausure of persistence, which is a measure of the speaker's topocal intent, reflects the topic's importance in the discourse. The third measure is a measure of ambiguity. This is necessary for assessing the disruptive effects that other topics within five previous clauses may have on topic identification. The more other topics are present within five previous clauses, the more difficult is the task of correct identification of a topic. The results of the present study show that the humanness of entities is the most powerful factior in topic continutiy in narrative discourse. The semantic roles of human arguments in narrative discourse tend to be agents or experiences. Since agents and experiences have high topicality in discourse, human entities clearly become clausal or discoursal topics. The results also show that the grammatical devices signal varying degrees of topic continuity discontinuity in continuous discourse. The more continuous a topic argument is, the less it is coded. For example, personal pronouns have the most continutiy and indefinite referentials have the least continutiy. The study strongly shows that topic continuity discontinutiy is controlled not only by grammatical devices available in the language but by socio-cultural factors and writer's intentions.

Height Datum Transformation using Precise Geoid and Tidal Model in the area of Anmyeon Island (정밀 지오이드 및 조석모델을 활용한 안면도 지역의 높이기준면 변환 연구)

  • Roh, Jae Young;Lee, Dong Ha;Suh, Yong Cheol
    • Journal of Korean Society for Geospatial Information Science
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    • v.24 no.1
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    • pp.109-119
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    • 2016
  • The height datum of Korea is currently separated into land and sea, which makes it difficult to acquire homogeneous and accurate height information throughout the whole nation. In this study, we therefore tried to suggest the more effective way to transform the height information were constructed separately according to each height datum on land and sea to those on the unique height datum using precise geoid models and tidal observations in Korea. For this, Anmyeon island was selected as a study area to develop the precise geoid models based on the height datums land (IMSL) and sea (LMSL), respectively. In order to develop two hybrid geoid models based on each height datum of land an sea, we firstly develop a precise gravimetric geoid model using the remove and restore (R-R) technique with all available gravity observations. The gravimetric geoid model were then fitted to the geometric geoidal heights, each of which is represented as height datum of land or sea respectively, obtained from GPS/Leveling results on 15 TBMs in the study area. Finally, we determined the differences between the two hybrid geoid models to apply the height transformation between IMSL and LMSL. The co-tidal chart model of TideBed system developed by Korea Hydrographic and Oceanographic Agency (KHOA) which was re-gridded to have the same grid size and coverage as the geoid model, in order that this can be used for the height datum transformation from LMSL to local AHHW and/or from LMSL to local DL. The accuracy of height datum transformation based on the strategy suggested in this study was approximately ${\pm}3cm$. It is expected that the results of this study can help minimize not only the confusions on the use of geo-spatial information due to the disagreement caused by different height datum, land and sea, in Korea, but also the economic and time losses in the execution of coastal development and disaster prevention projects in the future.

E-Commerce in the Historical Approach to Usage and Practice of International Trade ("무역상무(貿易商務)에의 역사적(歷史的) 어프로치와 무역취인(貿易取引)의 전자화(電子化)")

  • Tsubaki, Koji
    • THE INTERNATIONAL COMMERCE & LAW REVIEW
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    • v.19
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    • pp.224-242
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    • 2003
  • The author believes that the main task of study in international trade usage and practice is the management of transactional risks involved in international sale of goods. They are foreign exchange risks, transportation risks, credit risk, risk of miscommunication, etc. In most cases, these risks are more serious and enormous than those involved in domestic sales. Historically, the merchant adventurers organized the voyage abroad, secured trade finance, and went around the ocean with their own or consigned cargo until around the $mid-19^{th}$ century. They did business faceto-face at the trade fair or the open port where they maintained the local offices, so-called "Trading House"(商館). Thererfore, the transactional risks might have been one-sided either with the seller or the buyer. The bottomry seemed a typical arrangement for risk sharing among the interested parties to the adventure. In this way, such organizational arrangements coped with or bore the transactional risks. With the advent of ocean liner services and wireless communication across the national border in the $19^{th}$ century, the business of merchant adventurers developed toward the clear division of labor; sales by mercantile agents, and ocean transportation by the steam ship companies. The international banking helped the process to be accelerated. Then, bills of lading backed up by the statute made it possible to conduct documentary sales with a foreign partner in different country. Thus, FOB terms including ocean freight and CIF terms emerged gradually as standard trade terms in which transactional risks were allocated through negotiation between the seller and the buyer located in different countries. Both of them did not have to go abroad with their cargo. Instead, documentation in compliance with the terms of the contract(plus an L/C in some cases) must by 'strictly' fulfilled. In other words, the set of contractual documents must be tendered in advance of the arrival of the goods at port of discharge. Trust or reliance is placed on such contractual paper documents. However, the container transport services introduced as international intermodal transport since the late 1960s frequently caused the earlier arrival of the goods at the destination before the presentation of the set of paper documents, which may take 5 to 10% of the amount of transaction. In addition, the size of the container vessel required the speedy transport documentation before sailing from the port of loading. In these circumstances, computerized processing of transport related documents became essential for inexpensive transaction cost and uninterrupted distribution of the goods. Such computerization does not stop at the phase of transportation but extends to cover the whole process of international trade, transforming the documentary sales into less-paper trade and further into paperless trade, i.e., EDI or E-Commerce. Now we face the other side of the coin, which is data security and paperless transfer of legal rights and obligations. Unfortunately, these issues are not effectively covered by a set of contracts only. Obviously, EDI or E-Commerce is based on the common business process and harmonized system of various data codes as well as the standard message formats. This essential feature of E-Commerce needs effective coordination of different divisions of business and tight control over credit arrangements in addition to the standard contract of sales. In a few word, information does not alway invite "trust". Credit flows from people, or close organizational tie-ups. It is our common understanding that, without well-orchestrated organizational arrangements made by leading companies, E-Commerce does not work well for paperless trade. With such arrangements well in place, participating E-business members do not need to seriously care for credit risk. Finally, it is also clear that E-International Commerce must be linked up with a set of government EDIs such as NACCS, Port EDI, JETRAS, etc, in Japan. Therefore, there is still a long way before us to go for E-Commerce in practice, not on the top of information manager's desk.

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Building an Efficient Supply Chain by reduction of lead time with a Focus on Korea Server Manufacturer (리드타임 감소에 의한 효율적 공급체인 구축 - 국내 서버 공급체인을 대상으로 -)

  • 신용석;김태현;문성암
    • Journal of Distribution Research
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    • v.6 no.2
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    • pp.1-17
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    • 2002
  • The recent dot-com craze has been one of the main causes that accelerated the growth of internet-related companies in diversity as well as in size. Meanwhile, the domestic market of supplies and equipment for internet businesses has been dominated by major foreign companies. To regain their market positions, the domestic manufacturers had to find the way to build up their competitive advantages, such as meeting their customers needs and reducing overall costs. In this study, one domestic PC server manufacturer, which competes fiercely with foreign manufacturers for the top place, has been chosen as a model to evaluate its current supply chain and to find an area that can be improved for a better performance. System Dynamics is used throughout the study. The central concept to system dynamics is understanding how all the objects in a system interact with one another. It focuses on feedback and secondary effects to think through how a strategy might or might not work, depending on how organizational changes are received, and what kinds of consequences emerge. Then, computerized models were built for simulations, each with different conditions, and, finally, the results were evaluated based on some criteria which are considered to be important and meaningful. The inefficiency that exists in the supply chain was proved to be a thirty-day long purchasing order leadtime, and it was expected that more effective supply chain could be formed if the leadtme were reduced to 14 days or 7 days. The results of simulations showed that the overall expected costs in supply chain was the least with the purchasing leadtime being 7 days. The lower average number of parts held as inventory, along with the reduced lost sales, acted as the factor reducing the expected overall costs. Although there was a slight increase in the average number of final products held as inventory and the total ordering cost, the benefits from lower parts inventory and reduced lost sales were large enough to justify the overall cost reduction.

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