• Journal of Korean Elementary Science Education
• /
• v.40 no.1
• /
• pp.81-99
• /
• 2021

The purpose of this study is to develop scientist vignettes and to explore their effects to change students' perceptions of scientists, scientific attitudes, and the nature of science. The scientist vignettes developed in this study include research cases on seven scientists, including British zoologist Jane Goodall. Each vignette consists of 4 to 6 pages in consideration of the reading level of elementary school students, and contains illustrations describing the main contents of the text. In addition, scientist vignettes contain descriptions on terms and text boxes explaining the higher concepts, and each vignette contains questions that students can think deeply based on the story of the scientist. To verify the educational effectiveness of scientist vignettes, we investigated changes in their perceptions of scientists, scientific attitudes, and the nature of science in 564 elementary school students. We conducted group interviews with four elementary school teachers. As a result of conducting pre-test and post-test using a narrative questionnaire consisting of 6 questions, students became more sophisticated in the understanding of the science and the characteristics of scientists after experiencing scientist vignettes and their understanding the nature of science changed into a more modern epistemological perspective. Also, in a group interview with teachers, teachers assessed that scientist vignettes would positively affect the understanding of science process skills and the nature of science, and forming a scientific attitude, especially in increasing understanding of the nature of science. We discussed ways to effectively utilize scientist vignettes in elementary school science education based on these result.

• English & American cultural studies
• /
• v.9 no.1
• /
• pp.239-272
• /
• 2009

Our investigation of the intricate relationship among nationalism, humanism, and imperialism begins from reading Song of Ariran, the auto/biography of Kim San recorded by Nym Wales, together with Margaret Drabble's fictional adaptation of Lady Hong's autobiography, The Memoirs of Lady $Hyegy{\breve{o}}ng$, in her novel The Red Queen, in which the story of Barbara Halliwell, a modern female envoy of Lady Hong, is interweaved with Lady Hong's narrative. In spite of their being seemingly disparate texts, Song of Ariran and The Red Queen are comparable: they are written by Western female writers who deal with Koreans, along with the Korean history and culture. Accordingly, both works cut across the boundary of fiction and fact, imagination and history, and the East and the West. In the age of globalization, Western women writing (about) Korea and Koreans traversing the historical and cultural limits inevitably engage us in post-colonial discussions. Despite the temporal differences--If Song of Ariran handles with the historical turmoils of the 1930s Asia, mostly surrounding Kim San's activities as a nationalist, The Red Queen is written by a twenty-first century British woman writer whose international interest grapples with the eighteenth-century Korean Crown Princess' spirit in order to reinscribe a story of Korean woman's within the contemporary culture--, both works appeal to the humanistic perspective, advocating the universal human beings' values transcending the historical and national limitations. While this sort of humanistic approach can provide sympathy transcending time and space, this 'idealistic' process can be problematic because the Western writers's appropriation of Korean culture and its history can easily reduce its particularities to comprehensive generalization, without giving proper names to the Korean history and culture. Nonetheless, the Western female writers' attempt to find a place of 'contact' is valuable since it opens a possibility of having meaningful communications between minor culture and dominating culture. Yet, these female writers do not seem to absolutely cross the border of race, gender, and culture, which leaves us to realize how difficult it is to reach a genuine understanding with what is different from mine even in these 'universal' narratives.

• Korean Journal of Optics and Photonics
• /
• v.31 no.1
• /
• pp.1-6
• /
• 2020

The chest wall, an organ directly affected by environmental particles through respiration, consists of ribs, a pleural layer and intercostal muscles. To diagnose early and treat disease in this body part, it is important to visualize the details of the chest wall, but the structure of the pleural layer cannot be seen by chest computed tomography or ultrasound. On the other hand, optical coherence tomography (OCT), with a high spatial resolution, is suited to observe pleural-layer response to talc, one of the fine materials. However, intensity-based OCT is weak in providing information to distinguish the detailed structure of the chest wall, and cannot distinguish the reaction of the pleural layer from the change in the muscle by the talc. Polarization-sensitive OCT (PS-OCT) takes advantage of the fact that specific tissues like muscle, which have optical birefringence, change the backscattered light's polarization state. Moreover, the birefringence of muscle associated with the arrangement of myofilaments indicates the muscle's condition, by measuring retardation change. The PS-OCT image is interpreted from three major perspectives for talc-exposure chest-wall imaging: a thickened pleural layer, a separation between pleural layer and muscle, and a phase-retardation measurement around lesions. In this paper, a rabbit chest wall after talc pleurodesis is investigated by PS-OCT. The PS-OCT images visualize the pleural layer and muscle, respectively, and this system shows different birefringence of normal and damaged lesions. Also, an analyisis based on phase-retardation slope supports results from the PS-OCT image and histology.

• Archives of Reconstructive Microsurgery
• /
• v.5 no.1
• /
• pp.121-127
• /
• 1996

Peripheral nerve injury occurs mostly by trauma and is usually associated with fracture of bone and joint, muscular injury and tendon injury and it also evokes paralysis and anesthesia. When treatment of peripheral nerve injury is considered,, the modality of treatment is decided by the general condition of the patient, type of injury, associated injuries and the condition of wound. To get the maximum results, surgical treatment and reconstruction and rehabilitation should all go in hand-in-hand. From January 1985 to December 1994, we observed 61 patients that had operation without reconstruction due to peripheral nerve injury with a follow-up period of more than 1 year. Among the 61 patients, 44 were men(72%) and 17 were women(28%). Follow-up period was average 19 months. Age distribution was mostly in their twenties with a mean age of 28 years. Time interval of operation after injury was average 11 months. Trauma was the main cause of peripheral nerve injuries with a proportion of 87%. 31 patients had neurorrhaphy, in which case 14 patients had stay suture and 17 patients did not. 14 patients had nerve graft, and 16 patients had neurolysis. We used our scales to compare the results of surgery on the basis of British Research Council System. We gave scores to every sensory and motor scale to estimate functional improvement and emphasized on motor functional improvement. The total score = sensory score + ($2{\times}motor$ score). We considered 8-9 points as excellent, 6-7 points as good, 2-5 points as fair, 0-1 points as poor result. We considered excellent and good as much improved. Excellent and good results were obtained in 13 out of 14 neurorrhaphy with stay suture(93%), 12 out of 17 neurorrhaphy without stay suture(71%), 6 out of 14 nerve graft(43%), 12 out of 16 neurolysis(75%). Among the patients with neurorrhaphy done within 3 months, 11 out of 14(86%) showed improvement, but among the patients after 4 months 3 out of 17(76%) showed improvement. 84% of improvement was observed in the patients with time interval from injury to surgery within 3 months, and 64% in the patients with time interval after 4 months. In the aspect of age, 77% with the age below 20 years, 70% with the age between 21 and 30 years, 66% with the age above 31 years showed improvement. We conclude that considering degree of injury, time interval from injury and age with the adequate method of treatment, we can obtain good results from surgery.

• Asian-Australasian Journal of Animal Sciences
• /
• v.22 no.9
• /
• pp.1267-1278
• /
• 2009

Three beef steers fitted with permanent cannulae in the rumen and duodenum were used to determine the effects of protein supply from soyhulls (SH) and wheat bran (WB) on ruminal metabolism, blood metabolites, nitrogen metabolism, nutrient digestion and concentrations of soluble non-ammonia nitrogen (SNAN) in ruminal (RD) and omasal digesta (OD). In a 3${\times}$3 Latin square design, steers were offered rice straw and concentrates formulated either without (control) or with two brans to increase crude protein (CP) level (9 vs. 11% dietary DM for control and bran-based diets, respectively). The brans used were SH and WB that had similar CP contents but different ruminal CP degradability (52 vs. 80% CP for SH and WB, respectively) for evaluating the effects of protein degradability. Ruminal ammonia concentrations were higher for bran diets (p<0.01) than for the control, and for WB (p<0.001) compared to the SH diet. Similarly, microbial nitrogen and blood urea nitrogen were significantly increased (p<0.05) by bran and WB diets, respectively. Retained nitrogen tended (p<0.082) to be increased by SH compared with the WB diet. Intestinal and total tract CP digestion was enhanced by bran diets. In addition, bran diets tended (p<0.085) to increase intestinal starch digestion. Concentrations of SNAN fractions in RD and OD were higher (p<0.05) for bran diets than for the control, and for WB than for the SH diet. More rumendegraded protein supply resulting from a higher level and degradability of CP released from SH and WB enhanced ruminal microbial nitrogen synthesis and ruminal protein degradation. Thus, free amino acids, peptides and soluble proteins from microbial cells as well as degraded dietary protein may have contributed to increased SNAN concentrations in the rumen and, consequently, the omasum. These results indicate that protein supply from SH and WB, having a low level of protein (13 and 16%, respectively), could affect ruminal metabolism and nutrient digestion if inclusion level is relatively high (>20%).

• Journal of the Korean Wood Science and Technology
• /
• v.40 no.2
• /
• pp.110-122
• /
• 2012

This study investigated the effects of layered clay on the thermal curing behavior and tensile properties of resole phenol-formaldehyde (PF) resin/clay/cellulose nanocomposites. The thermal curing behavior of the nanocomposite was characterized using conventional differential scanning calorimetry (DSC) and temperature modulated (TMDSC). The addition of clay was found to accelerate resin curing, as measured by peak temperature ($T_p$) and heat of reaction (${\Delta}H$) of the nanocomposite’ curing reaction increasing clay addition decreased $T_p$ with a minimum at 3~5% clay. However, the reversing heat flow and heat capacity showed that the clay addition up to 3% delayed the vitrification process of the resole PF resin in the nanocomposite, indicating an inhibition effect of the clay on curing in the later stages of the reaction. Three different methods were employed to determineactivation energies for the curing reaction of the nanocomposite. Both the Ozawa and Kissinger methods showed the lowest activation energy (E) at 3% clay content. Using the isoconversional method, the activation energy ($E_{\alpha}$) as a function of the degree of conversion was measured and showed that as the degree of cure increased, the $E_{\alpha}$ showed a gradual decrease, and gave the lowest value at 3% nanoclay. The addition of clay improved the tensile strengths of the nanocomposites, although a slight decrease in the elongation at break was observed as the clay content increased. These results demonstrated that the addition of clay to resole PF resins accelerate the curing behavior of the nanocomposites with an optimum level of 3% clay based on the balance between the cure kinetics and tensile properties.

• International Journal of Highway Engineering
• /
• v.19 no.1
• /
• pp.53-62
• /
• 2017

PURPOSES : This research was a fundamental study on the application of an integral $TiO_2$ solution to asphalt concrete pavement. The integral $TiO_2$ solution was produced in pilot production equipment; application of the integral $TiO_2$ solution to asphalt pavement was conducted to examine the pollution-reducing capability of photocatalytic compounds such as $TiO_2$. The photocatalytic $TiO_2$ reacted with air pollutants, converting them into small amounts of relatively benign molecules. METHODS : In this study, laboratory experiments were conducted using five various testing methods. Tensile strength ratio (TSR) and British pendulum test (BPT) were conducted in order to evaluate the properties of asphalt pavement subsequent to the integral $TiO_2$ solution coating. In addition, methylene blue testing, a measurement of nitrate on the coated pavement, and nitrogen oxide (NOx) reduction testing were conducted in order to evaluate photocatalytic reaction. Lastly, a UV-A lamp was used as a light source for photocatalytic reactions. RESULTS : Test results indicated no change in the properties of asphalt pavement following the integral $TiO_2$ solution coating. In order to evaluate the performance of asphalt pavement as a function of $TiO_2$, the moisture susceptibility and skid resistance were investigated. The moisture susceptibility and skid resistance satisfied there quirements related to pavement quality and safety specification. Furthermore, the effects of reduction of air pollution were significantly improved as determined via the methylene blue test and NOx reduction test. The $TiO_2$-paved asphalt specimen exhibited approximately 43% reduction of NOx. CONCLUSIONS : This study has suggested that applying $TiO_2$ rarely impacts asphalt pavement performance measures such as moisture susceptibility and skid resistance, and that its application may be a better means of reducing air pollution. Further studies, such as proper $TiO_2$ dosage rates and compatibility with various pavement types, are required to broaden and generalize its application.

• Journal of Korea Technical Association of The Pulp and Paper Industry
• /
• v.38 no.3 s.116
• /
• pp.29-37
• /
• 2006

To use bamboo in the pulp industry, the anatomical characteristics of 60-day-old, 1-year-old, 2-year-old, and 3-year-old moso bamboo (Phyllostachys pubescens Mazel), and the characteristics of fiber and sheet of alkali pulp made of moso bamboo were investigated. Moso bamboo is composed of metaxylens and parenchyma cells in the inner part of the wall, and thick-walled small bundle sheathes near the outer walls. Moso bamboo showed the heterogeneity in anatomical structure. The longest fibers were shown in the middle part, and the widest width in the inner part. The lignin contents were 14.4% in 60-day-old bamboo, which was not lignified yet. The lignin contents in bamboo above 1 year were approximately 35%. The yields of alkali pulp of moso bamboo were in the range between 41 and 47%, and the yields tend to decrease with the increase of ages. The lignin contents of 60-day-old bamboo were 2.1% and those of bamboo above 1 year showed approximately 4% to 5% increment. The length, width, and curl index of fiber in alkali pulp appeared to be similar in all ages. However, coarseness increased slightly with the increase of bamboo ages. The distribution of long fiber was shown much in 60-year-old bamboo. The optical and mechanical properties of moso bamboo tended to decrease with the increase of bamboo age.

• Journal of Environmental Health Sciences
• /
• v.32 no.5 s.92
• /
• pp.404-411
• /
• 2006

이 연구의 목적은 유치원에서 총 휘발성 유기화합물의 농도를 평가하고, 총 휘발성 유기화합물 농도와 대표적인 8개 방향족 화합물의 상관관계를 조사하는데 있다. 도시에 위치한 11개 유치원의 실내와 실외에서 각각 30개, 11개의 지역시료를, 시골에 위치한 4개 유치원에서는 각각 10개, 4개의 시료를 테낙스 튜브를 이용하여 오전에 1-2시간 채취하였다. 채취한 시료는 열탈착하여 가스크로마토그래피-질량분석기로 분석하였다. 13가지 물질을 각각의 표준물질로 개별 정량하여 이중 빈번히 발견되는 8가지 방향족 유기화합물은 상관관계 평가에 사용하였다. 총 휘발성 유기화합물은 톨루엔을 기준으로 정량하였다. 도시에 위치한 유치원 실내의 총 휘발성 유기화합물 농도가 높았고, 조사 건수의 50%가 환경부 및 교육인적자원부의 가이드라인($400{\mu}g/m^{3}$)을 초과하였다. 도시지역의 유치원 실내 및 실외의 기하평균은 각각 $387.9{\mu}g/m^{3}$과 $134.9{\mu}g/m^{3}$이었고, 시골지역 유치원에서는 각각 $189.6{\mu}g/m^{3},;74.4{\mu}g/m^{3}$이었다. 톨루엔, 크실렌, 에틸벤젠, 정량한 유기 화합물 총합, 총 휘발성 유기화합물은 기하정규분포를 하였다. 벤젠, 톨루엔, 에틸벤젠, 크실렌(BTEX)은 도시에 위치한 유치원에서 농도도 높고, 총 휘발성 유기화합물중 함량도 높았고, 시골지역에서는 농도와 상대적 함량이 낮았다. 도시지역에서는 총 휘발성 유기화합물 중 BTEX의 비중이 25.2%였고 정량한 13가지 유기화합물 중에서는 35.6%를 차지하였다. BTEX 각각 개별물질은 미국 환경보호청이 제시하는 일일 노출 기준량(Reference Concentration; RfC) 보다는 현저히 낮았다. 총 휘발성 유기화합물읜 농도는 실내가 실외 보다 높았다(I/O ratio 2.5). BTEX의 상대적 함량도 실내가 실외보다 높아 실내에도 발생원이 있음을 암시하고 있다. 자료 분석결과 유치원 실내의 벤젠은 실외로부터 유입되고 있었고, 톨루엔, 에틸벤젠, 크실렌은 실외뿐 아니라 실내에서도 발생하고 있었다. 정량한 8개 화합물 각각과 총 휘발성 유기화합물의 스피어만 상관계수는 벤젠을 제외하고는 모두 유의하였다. 이중 톨루엔과 크실렌은 총 휘발성 유기화합물과 좋은 상관성 (톨루엔 0.76, 크실렌, 0.87)을 나타내었다. 이 연구는 톨루엔과 크실렌이 총 휘발성 유기화합물의 좋은 지표를 사용될 있고, 톨루엔, 에틸벤젠, 크실렌 등 많은 휘발성 유기화합물의 발생원은 실외뿐 아니라 실내에도 있음을 나타내고 있다.

• Clinical and Experimental Pediatrics
• /
• v.54 no.11
• /
• pp.463-469
• /
• 2011

Purpose: To validate the Dinamap ProCare 200 blood pressure (BP) monitor against a mercury sphygmomanometer in children 7 to 18 years old in accordance with the 2010 International Protocol of European Society of Hypertension (ESH-IP2) and the British Hypertension Society (BHS) protocol. Methods: Forty-five children were recruited for the study. A validation procedure was performed following the protocol based on the ESH-IP2 and BHS protocols for children and adolescents. Each subject underwent 7 sequential BP measurements alternatively with a mercury sphygmomanometer and the test device by trained nurses. The results were analyzed according to the validation criteria of ESH-IP2. Results: The mean (${\pm}SD$) difference in the absolute BP values between test device and mercury sphygmomanometer readings was $1.85{\pm}1.65$ mmHg for systolic BP (SBP) and $4.41{\pm}3.53$ mmHg for diastolic BP (DBP). These results fulfilled the Association for the Advancement of Medical Instrumentation criterion of a mean${\pm}$SD below $5{\pm}8$ mmHg for both SBP and DBP. The percentages of test device-observer mercury sphygmomanometer BP differences within 5, 10, and 15 mmHg were 96%, 100%, and 100% for SBP, and 69%, 92%, and 100% for DBP, respectively, in the part 1 analysis; both SBP and DBP passed the part 1 criteria. In the part 2 analysis, SBP passed the criteria but DBP failed. Conclusion: Although the Dinamap ProCare 200 BP monitor failed an adapted ESH-IP2, SBP passed. When comparing BP readings measured by oscillometers and mercury sphygmomanometers, one has to consider the differences between them, particularly in DBP, because DBP can be underestimated.