• Horticultural Science & Technology
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• v.29 no.5
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• pp.389-406
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• 2011

As part of a feasibility study for introducing carbon labeling of fruit products in Korea, we explore the use of carbon footprints for Korean kiwifruit from Gyeongnam region as a case study. In Korea, the Korean Environmental Industry and Technology Institute (KEITI) is responsible for the carbon footprint labeling certification, and has two types of certification programs: one program focuses on climate change response (carbon footprint labeling analysis) and the other on low-carbon products (reduction of carbon footprints analysis). Currently agricultural products have not yet been included in the program. Carbon labeling could soon be a prerequisite for the international trading of agricultural products. In general the carbon footprints of various agricultural products from New Zealand followed the methodology described in the ISO standards and conformed to the PAS 2050. The carbon footprint assessment focuses on a supply chain, and considers the foreground and the background systems. The basic scheme consists of four phases, which are the 'goal', 'scope', 'inventory analysis', and 'interpretation' phases. In the case of the carbon footprint of New Zealand kiwifruit the study tried to understand each phase's contribution to total GHG emissions. According to the results, shipping, orchard, and coolstore operation are the main life cycle stages that contribute to the carbon footprint of the kiwifruit supply chain stretching from the orchard in New Zealand to the consumer in the UK. The carbon emission of long-distance transportation such as shipping can be a hot-spot of GHG emissions, but can be balanced out by minimizing the carbon footprint of other life cycle phases. For this reason it is important that orchard and coolstore operations reduce the GHG-intensive inputs such as fuel or electricity to minimize GHG emissions and consequently facilitate the industry to compete in international markets. The carbon footprint labeling guided by international standards should be introduced for fruit products in Korea as soon as possible. The already established LCA methodology of NZ kiwifruit can be applied for fruit products as a case study.

• The Korean Journal of Petroleum Geology
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• v.6 no.1_2 s.7
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• pp.25-36
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• 1998

Organic geochemical analyses were carried out in order to characterize organic matter (OM) in the sediments recovered from Korea/japan Joint Development Zone (JDZ V-1, V-3, VII-1 and VII-2) which is located in the northern end of the East China Sea Shelf Basin. Late Miocene sediments from the JDZ V-1 and V-3 wells generally contain less than $0.5\%$ of total organic carbon (TOC). However, early Miocene and Oligocene sediments show TOC values of $0.6-0.8\%$. Middle to late Miocene sediments are rich in TOC up to $20\%$ from JDZ VII-1 and JDZ VII-2 wells. The reason for this rich TOC might be attributed to the presence of coaly shales. Kerogens in the Tertiary sediments from the JDZ series wells are mainly composed of terrestrially derived woody organic matter. Elemental analyses indicate that OM from these wells can be compared to type III. Low hydrocarbon potential and hydrogen index reflect the type of OM. According to the biomarker analyses, the input of the terrestrial OM is prevalent. Oxidizing condition is also indicated by Pristane/Phytane ratio. Samples from the JDZ V-1 and V-3 wells obtain maturities equivalent to the oil generation zone around total depth, and organic matter below 3600 m from JDZ VII-1 and VII-2 wells reached dry gas generation stage. Oligocene sediments below 3500 m in the JDZ VII-1 and JDZ VII-2 wells may have generated limited amount of hydrocarbons, showing a progressive decrease in hydrogen index with depth, due to thermal degradation with increased burial. Gas shows and finely disseminated gilsonite may indicate the generation and migration of the hydrocarbons.

• Bulletin of the Society of Naval Architects of Korea
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• v.25 no.4
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• pp.69-80
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• 1988

This paper proposes simple formulae for buckling and ultimate strength estimation of plates subjected to water pressure and uniaxial compression. For the construction of a formula for elastic buckling strength estimation, parametric study for actual ship plates with varying aspect ratios and the magnitude of water pressure is carried out by means of principle of minimum potential energy. Based on the results by parametric study, a new formula is approximately expressed as a continuous function of loads and aspect ratio. On the other hand, in order to get a formula for ultimate strength estimation, in-plane stress distribution of plates is investigated through large deflection analysis and total in-plane stresses are expressed as an explicit form. By applying Mises's plasticity condition, ultimate strength criterion is then derives. In the case of plates under relatively small water pressure, the results by the proposed formulae are in good agreement compared with those by other methods and experiment. But present formula overestimates the ultimate strength in the range of large water pressure. However, actual ship plates are subjected to relatively small water pressure except for the impact load due to slamming etc.. Therefore, it is considered that present formulae can be applied for the practical use.

• The Mathematical Education
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• v.61 no.2
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• pp.339-357
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• 2022

This study explores pre-service secondary mathematics teachers (PSTs)' noticing competency. 17 PSTs participated in this study as a part of the mathematics teaching method class. Individual PST's essays regarding the question 'what effective mathematics teaching would be?' that they discussed and wrote at the beginning of the course were collected as the first data. PSTs' written analysis of an expert teacher's teaching video, colleague PSTs' demo-teaching video, and own demo-teaching video were also collected and analyzed. Findings showed that most PSTs' noticing level improved as the class progressed and showed a pattern of focusing on each key aspect in terms of the Teaching for Robust Understanding of Mathematics (TRU Math) framework, but their reasoning strategies were somewhat varied. This suggests that the TRU Math framework can support PSTs to improve the competency of 'what to attend' among the noticing components. In addition, the instructional reasoning strategies imply that PSTs' noticing reasoning strategy was mostly related to their interpretation of noticing components, which should be also emphasized in the teacher education program.

• Sim-seong Yeon-gu
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• v.28 no.1
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• pp.1-49
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• 2013

This article started with 'encounter'. Both authors met around the middle of February and discussed the subject for the inhospital conference presentation scheduled at the break of June. Having conversation like "Movies similar to fairytales heard from childhood are standing out conspicuously among commercial films which are attracting audiences and receiving fervent response these days. This phenomenon is marvelous and mysterious." together, and sharing this and that, the conversation turned naturally to 'Bram Stoker's Dracula', 'Series of Twilight', and 'Warm Bodies', both authors found out the fact that we saw these movies in common with propound impression. Feeling our hearts beating high, bit of fear and hesitation followed simultaneously at the moment when both of us encountered the idea to choose subject of conference presentation related to this and expressed one in words. While preparing for the conference, presenting to others, and having discussion with the audience, our hearts have been filled with Presentation was finished after active discussion beyond fixed hour and it also brought audience (among those present) to show strong emotional response both positively and negatively. At first, we just had a thought to put aside the content of presentation, but we felt lack of something else, lingering in our minds. We finally decided to accomplish our work into an article leading to submission, based on the advice and recommendation from one of the audience. This article is a small 'creative writing' born by sharing both authors' passion and enthusiasm. In the first part of this article, we have introduced the dream of 31-year-old woman's which led to the 'creative writing' and spotlighted her personal life, before and after the dream. In the second part, we have examined the consequence (way of realization) and meaning of creative impulse shown from or experienced from personal unconsciousness (dream, fantasy) together. Creative impulse shown from the individual appeared to bring creative transformation of individual personality through the process of 'introversion'. Otherwise it also appeared to be delivered as a masterpiece through 'creative writing' or from the process of 'extroversion'. Sometimes both consequences happened at once. We tried to examine and interpret the dream of 31-year-old woman's, which was introduced in the first part of this article, that is to say, the dream of 'Stephenie Meyer's, the author of the 'love between vampire boy and ordinary human girl' themed novel 'Twilight Series', in a psychoanalytic perspective. In the third part, highlighting individual dreams and three different movies 'Bram Stoker's Dracula', 'Twilight Series', and 'Warm Bodies', we found the transformation of symbol 'Man of Darkness, vampire' seen in each individual dreams and in some specific popular arts, such as novels and movies, receiving fervent response from people. We also found love between this symbol and humane woman, bearing fruit together with very impressive change shown in the attitude of 'Man of Darkness' (vampire)'s conscious ego and mutual relationship pattern. We contemplated this phenomenon, the reason why these events happen, and what kind of association presents among these events, individual, and this era and discussed the effects on individuals and this era, at present. 'Creative impulse', originated in the deep structure of human mind is realized as a 'transformation of individual personality' or masterpiece through artistic creation. If it has a chance to make a match with this era, shared by a lot of contemporary people, it also appears to bring positive effect as healing and salvation to each individual or to each era. From this article, we mainly highlighted positive and healing aspects of individual 'creative impulse'. We hope to deal with the negative consequences and their reason coming from 'creative impulse', if the occasion arises, in the future with a new article.

• Communications of Mathematical Education
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• v.29 no.3
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• pp.553-571
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• 2015

Mathematical, verbal, and spatial abilities are known as three important indicators for the success in the STEM disciplines. In this study, Purdue Spatial Visualization Test-Rotation, College Entrance Scholastic Aptitude Test- Math and Verbal score of engineering freshmen students have been used to find the relationships among these areas. In addition, gender differences in spatial visualization, verbal achievement and mathematical achievement have been investigated, too. In this research, I found that gender difference was highest in spatial visualization ability, followed by verbal achievement and smallest in mathematical achievement. Substantial number of male students possess high level of spatial abilities, but only half of female students were at the same level where their male colleagues were. The correlation between spatial ability and mathematical ability was negligible, contrary to former researches on elementary and middle school students. But the correlation was stronger for female students than male students. The correlation between mathematical achievement and verbal achievement was negative. It reflects the fact that when one section of SAT score is low, score of other sections should be higher to get admitted to college. Gender difference in mathematics was smallest for high achieving spatial ability group. For low spatial ability group gender difference in mathematics achievement has been observed, too. To find the combined contribution of spatial and verbal abilities to mathematics achievement, students were divided into 4 ability groups. Mathematics achievement decreased in the order of (1) high spatial -low verbal group, (2) low spatial - low verbal group, (3) high spatial - high verbal group, (4) low spatial - high verbal group.

• Education of Primary School Mathematics
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• v.15 no.2
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• pp.107-134
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• 2012

The purpose of this study is to investigate the effectiveness of two teaching methods of word problems, one based on mathematical modeling learning(ML) and the other on traditional learning(TL). Additionally, the influence of mathematical modeling learning in word problem solving behavior, application ability of real world experiences in word problem solving and the beliefs of word problem solving will be examined. The results of this study were as follows: First, as to word problem solving behavior, there was a significant difference between the two groups. This mean that the ML was effective for word problem solving behavior. Second, all of the students in the ML group and the TL group had a strong tendency to exclude real world knowledge and sense-making when solving word problems during the pre-test. but A significant difference appeared between the two groups during post-test. classroom culture improvement efforts. Third, mathematical modeling learning(ML) was effective for improvement of traditional beliefs about word problems. Fourth, mathematical modeling learning(ML) exerted more influence on mathematically strong and average students and a positive effect to mathematically weak students. High and average-level students tended to benefit from mathematical modeling learning(ML) more than their low-level peers. This difference was caused by less involvement from low-level students in group assignments and whole-class discussions. While using the mathematical modeling learning method, elementary students were able to build various models about problem situations, justify, and elaborate models by discussions and comparisons from each other. This proves that elementary students could participate in mathematical modeling activities via word problems, it results form the use of more authentic tasks, small group activities and whole-class discussions, exclusion of teacher's direct intervention, and classroom culture improvement efforts. The conclusions drawn from the results obtained in this study are as follows: First, mathematical modeling learning(ML) can become an effective method, guiding word problem solving behavior from the direct translation approach(DTA) based on numbers and key words without understanding about problem situations to the meaningful based approach(MBA) building rich models for problem situations. Second, mathematical modeling learning(ML) will contribute attitudes considering real world situations in solving word problems. Mathematical modeling activities for word problems can help elementary students to understand relations between word problems and the real world. It will be also help them to develop the ability to look at the real world mathematically. Third, mathematical modeling learning(ML) will contribute to the development of positive beliefs for mathematics and word problem solving. Word problem teaching focused on just mathematical operations can't develop proper beliefs for mathematics and word problem solving. Mathematical modeling learning(ML) for word problems provide elementary students the opportunity to understand the real world mathematically, and it increases students' modeling abilities. Futhermore, it is a very useful method of reforming the current problems of word problem teaching and learning. Therefore, word problems in school mathematics should be replaced by more authentic ones and modeling activities should be introduced early in elementary school eduction, which would help change the perceptions about word problem teaching.

• Communications of Mathematical Education
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• v.16
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• pp.217-218
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• 2003

제7차 교육과정의 기본방향인 '21세기의 세계화 정보화 시대를 주도할 자율적이고 창의적인 한국인 육성'에서 볼 수 있듯이, 새로운 교육과정에서는 학생들의 창의력을 신장시키기 위한 방안으로 교과별 교육과정이나 재량활동 운영 등을 제시한 바 있다. 수학교육에서도 이러한 시대적 흐름에 발맞추어 수학적 창의력의 신장이 강조되고 있는 상황이다. 그동안 이론적인 측면과 실제적인 측면에서 수학적 창의성에 대한 성과가 축적되었다. 이론적인 측면에서 볼 때, Haylock(1987)등에 의해 창의력과 수학적 창의력의 구분되었으며, 특히 '수학적' 창의력에 대한 다양한 정의가 제안되었다. 실제적인 측면에서도 수학적 창의력을 측정하려는 평가 도구들이 그 동안 여러 가지로 개발하였다. 그러나, 이러한 수학적 창의력에 관한 전반적인 연구는 종국적으로 교실 수학수업에 반영되어야 함에도 불구하고, 그리 만족스럽지 못한 상황이다. 특히, 교실에서 수학수업을 실제로 담당하는 교사들이 수학적 창의력을 위한 수업을 하고자 하더라도 당장 가까이에서 구할 수 있는 교수 학습 자료가 여전히 부족한 상황이다. 물론 그 동안 교실 수학수업에서 사용할 수 있는 창의력 개발 프로그램이 전무한 것은 아니다. 그런데 그들 대부분은 게임이나 퍼즐을 이용한 것으로 그 수준이 단순 흥미유발에 그치고 있거나 소수의 영재아를 위한 소재를 중심으로, 특히 수학적 사고 과정을 따르기보다는, 시행착오를 거쳐 원하는 결과를 얻을 가능성이 많으며, 수학과의 연계성이 불분명한 채로 단순놀이에 그치는 경우가 적지 않아, 수업과 연관되어 창의력의 신장이라는 측면에서 볼 때, 적용하기 어려운 사례가 많다. 이러한 상황을 개선하는 데 기여하고자, 현재 교과교육공동연구 지원사업의 하나로 한국 학술 진흥재단의 지원을 받아, '개방형 문제(open-ended problems)'를 중심 소재로 한 '수학적 창의성'을 신장하기 위한 교수학습 프로그램을 개발하여, 중학교 1학년을 대상으로 연구를 진행하고 있다. 개방형 문제라 함은 명백한 정의가 어렵지만 Pehkeon(1995)는 개방형문제의 정의를 명백히 하기위한 시도로서 그 반대로 닫힌 문제에 대한 정의로부터 시작하여, 어떤 문제가 닫혀있다고 하는 것은 그 문제의 출발 상황과 목표 상황이 닫혀 있는 것, 즉 명백히 설명되어있을 때라면 개방형 문제는 이와 반대의 개념임을 시사하였다. Silver(1995)는 개방형 문제를 문제 자체가 다른 해석이 가능하거나 서로 다를 인정할만한 답을 가질 수 있는 문제 또는 풀이과정이 다양한 문제, 자연스럽게 다른 문제들을 제안하거나 일반화를 제시할 수 있는 문제라고 정의하였다. 따라서 개방형 문제란 출발상황이나 목표 상황의 일부가 닫혀있지 않을 때를 말하고 문제의 조건을 만족하는 해답이 여러 가지로 존재하는 문제를 뜻한다. 수학적 창의력을 개발하는 데, 다른 문제 유형보다도, 개방형 문제가 유리하다는 점은 이미 여러 학자들에 의해 주장되어왔다. 미국 국립영재교육센터(NRCG/T)는 기존의 사지선다형이나 단답형 문제와 질문들은 학생들의 사고 능력에 관한 정보를 거의 알려주지 못하기 때문에 한 가지 이상의 답을 요구하는 ‘open-ended' 또는 ’open-response' 문제와 질문을 가지고 수학 분야에서의 창의적 사고 능력과 표현능력을 측정해야 한다고 하였고, 개방형 문제가 일반적으로 정답이 하나인 문제보다 고차원적인 사고를 요구하게 하는 문제 형태라고 하였다. 본 연구에서는 이러한 근거를 바탕으로 개방형 문제의 유형을 다양한 답이 존재하는 문제, 다양한 해결 전략이 가능한 문제, 답이 없는 문제, 문제 만들기, 일반화가 가능한 문제 등으로 보고, 수학적 창의성 중 특히 확산적 사고에 초점을 맞추어 개방형 문제가 확산적 사고의 요소인 유창성, 독창성, 유연성 등에 각각 어떤 영향을 미치는지 20주의 프로그램을 개발, 진행하여 그 효과를 검증하고자 한다. 개방형 문제를 활용한 수학적 창의력 신장 프로그램을 개발하고 현장 학교에 실험 적용하여 그 효과를 분석하고자 하는 본 연구는 창의력 신장에 비중을 두는 수학과 교수-학습 과정에 실제적인 교수 학습 자료를 제공하는 것뿐만 아니라 교사들에게는 수학교실에서 사용 가능한 실제적인 활용방안을, 학생들에게는 주어진 문제를 여러 가지 각도에서 생각하면서 다양한 사고를 경험하는 기회를 가질 수 있어, 수학을 보는 학생들의 태도에도 긍정적인 변화를 가져올 수 있을 것이라 기대한다.