• The Journal of Engineering Geology
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• v.18 no.2
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• pp.127-136
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• 2008

Geophysical survey for establishing a wide site for the distribution of water content, wetting front infiltration due to the rainfall, and distribution of groundwater level has been performed by using 8round penetration radar (GPR) method, electrical resistivity method, and so on. On the other hand, a narrow area survey was performed to use a permittivity method such as time domain reflectometry, frequency domain reflectometry, and amplitude domain reflectometry methods for estimating volumetric water content, soil density, and concentration of contaminant in surface and subsurface. The permittivity methods establish more corrective physical parameters than different found survey technologies mentioned above. In this study for establishment of infiltration behaviors for wetting front in the unsaturated soil caused by an artificial rainfall, soil physical parameters for volumetric water content, pore water pressure, and pore air pressure were measured by FDR measurement device and pore water pressure meter which are installed in the unsaturated weathered granite soil with different depths. Consequently, the authors were proposed to a new establishment method for analyzing the variations of volumetric water content and wetting front infiltration from the responses of infiltrating pore water in the unsaturated soil.

• Applied Microscopy
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• v.29 no.2
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• pp.177-187
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• 1999

Ultrastructure of gametes in the three-spine stickleback, Gasterosteus aculeatus aculeatus was observed, utilizing light, scanning and transmission electron microscopes. The egg of three-spine stickleback is spherical and demersal type. The eggs are highly adhesived to each other but not to substrates. There are many oil droplets in vitelline membrane. The outer surface of egg envelope is arranged by mushroom-like structures and pore canals. The egg have a micropyle, sperm entry site, in the area of the animal pole. The egg envelope consists of three layers, an outer layer with high electron density, a middle layer consisting two layers and an inner layer consisting of 16 to 20 layers. In the fertilized egg envelope, the molecular weights of these components ranged from 14 kDa to 205 kDa. The molecular weights of nam protein bands are 19.4 kDa, 36.7 KDa, 39.4 kDa, 42.9 kDa, 46.1 kDa and 53.0 kDa. The head of spermatozoa is spherical shape and the acrosome is absent. The mitochondria in midpiece are arranged from one to three layers and separated from the axoneme by the cytoplasmic canal. The tail has two lateral fins and the axoneme is of the 9+2 structure.

• Journal of Sensor Science and Technology
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• v.6 no.5
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• pp.385-391
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• 1997

An objection of this study is to develop a measuring circuit of a gauge using radioisotope for compaction control. The gauge developed in this study makes use of radioisotope with the activity exempted from domestic atomic law and consists of measuring circuits for gamma-rays and thermal neutrons, a high voltage supply unit, and a microprocessor. To obtain meaningful numbers of pulse counts, parallel five and two circuits are provided for gamma-rays and thermal neutrons, respectively. Being simple in electrical characteristics of G-M detector for gamma-rays, pulses are counted through only a shaping circuit. Very small pulses generated from He- 3 proportional detector for thermal neutrons are amplified to the maximum of 50 [dB] and a window comparator accepts only pulses with meaning. To minimize effects of natural environmental radiation and electrical noise, circuits are electrostatically shielded and pulses made by ripples are eliminated by taking frequency of high voltage supplied to the circuit and pulse height of ripples into consideration. One-chip microprocessor is applied to process various counts, results are stored and the gauage is made capable to communicate with PC. Enough and meaningful numbers of pulses are counted with the prototype gauage for compaction control.

• Journal of Sensor Science and Technology
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• v.6 no.5
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• pp.423-429
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• 1997

We fabricated PLT thin films on ITO substrate for flat pannel display and investigated the characteristics, then we applicated to electroluminescent device and investigated application possibility. When we fabricated PLT thin films with substrate temperature of $500^{\circ}C$, and pressure of 30 mTorr, the relative deielectric constant and breakdown electricfield of PLT thin films were 120 and 3.2MV/cm. The electric resistivity was $2.0{\times}10^{12}{\Omega}{\cdot}cm$. PLT thin films had polycrystal structure of perovskite and pyrochlore at the higher substrate temperature than $450^{\circ}C$, and had good crystallinity at higher pressure. To use PLT insulator film and ZnS:Mn phosphor, we fabricated thin film electroluminescent device of ITO/PLT/ZnS:Mn/PLT/Al structure. At the result, threshold voltage was $35.2V_{rms}$ and brightness was $2400cd/m^{2}$ at $50V_{rms}$ and 1kHz. Maximum luminescence efficiency was 0.811m/W.

• Journal of Science Education
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• v.35 no.1
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• pp.91-101
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• 2011

In this study, Jigsaw III cooperative learning strategy and traditional learning strategy have been applied to the 'electricity' chapter of grade 8 science textbooks to know the effects of learning strategy, gender, and GPA on the students' science achievement and science learning attitude of middle school female students in gender-separated classes. For this purpose, 143 students of 4 classes in separated classes were chosen from a middle school in Daegu. One female class and one male class were assigned to the experimental group and other female class and male class were assigned to the control group. Traditional learning strategy was applied to the control group and the Jigsaw III cooperative learning strategy was applied to the experimental group. Four worksheets for expert groups were used for 18 hours through 5 weeks. Both tests for science achievement and learning attitude were administered as pre and post test. The test results were analyzed through analysis of covariance(ANCOVA) as pre test score as covariant The overall conclusions of this study were as follows: The Jigsaw III cooperative learning has improved science achievement, especially on subjective-type questions, of female students and mid-lower level students. The Jigsaw III Cooperative Learning has also improved self-directed attitude toward science learning. Female students have expressed more positive opinion about the Jigsaw III cooperative learning.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 1999.11a
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• pp.401-406
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• 1999

생활이 풍족해질수록 사람들은 음식이나 음료를 통하여 미각을 즐기는 경향이 강해지고 있다. 미각이 발달한 사람들은 다른 감각이 발달한 사람들보다 소비 욕구가 왕성하여 상품정보에 밝은 편이고 신제품에 대한 호기심도 많아 주요고객으로 환영받을 수 있는 가능성이 매우 높다. 이러한 점을 고려할 때 미각은 소비성향의 척도가 될 수 있으며, 이것이 상품개발에 중요한 지표가 될 가능성이 있다. 그러나 맛에 민감하다거나 둔감하다고 표현되는 개인의 미각물질에 대한 감도는 개인마다 일정치 않다. 이것은 미각물질에 따라 개인의 상대적인 역치의 고조나 미각 강도의 대소가 다르거나 감도가 다른 미각물질에 대한 수용구조에 개인차가 있기 때문이다. 이처럼 개인차가 있는 미각을 표준화된 방법으로 측정하는 것은 그리 쉬운 일이 아니다. 미각강도 측정을 위한 Time-Intensity curve는 1958년 음식물의 특성에 대해 관심을 가졌던 Nielson에 의해 개발되었는데 최근에 Takagi와 Asakura가 Time-Intensity curve분석과 기록을 위해 microcomputer를 이용한 방법을 개발하였다. 그들의 방범은 Time-Intensity curve를 모니터에 보여주고 data를 floppy discs에 기록하여 software로 분석하는 것이다. 본 연구는 이것을 좀더 편리하고 단순하게 만들기 위해 감각의 강도를 전기적 저항의 interface를 통하여 computer에 입력하는 대신에 mouse를 이용하여 입력하는 방법을 개발하였다. 새로이 개발된 Time-Intensity curve를 이용하여 커피성분 중 설탕과 프림의 농도에 변화를 주어 맛의 좋고 싫음의 미각강도를 측정하는 실험을 하였다. 그 결과 상품개발의 중요한 지표가 되는 미각의 강도를 측정할 수 있었고 이것은 향후 commercial한 상품의 개발에 유용한 지표가 될 것이라고 본다.시사한다. 본 연구에서는 한국 연구 조직에서 일하는 외국인 연구자들의 동기 및 성과에 영향을 미치는 많은 요인들을 확인할 수 있었다. 상관관계, 분산분석, 회귀분석 등을 통해 활용 성과에 미치는 영향 요인들을 도출하였다. 설문 분석을 통하여 동기 및 성과 사이에는 강한 상관관계가 존재하는 것을 확인할 수 있었으며 이는 전통적인 동기 이론들과 부합한다. 대부분의 변수가 동기 및 성과에 동시에 영향을 미치는 것으로 조사되었으며 그중에서도 조직 협력 문화, 외국인 연구자의 의사소통 및 협력성, 외국인 연구자의 연구 능력 관련 변수들 및 연구 프로젝트의 기술수명주기, 외국인 연구자의 기존 기술지식의 흡수 등이 가장 중요한 변수로 나타났다. 이는 우리가 주로 중국 및 러시아 과학자들을 활용하여 상업화하는 외국인 연구인력 활용 패턴과도 일치하는 결과이다. 즉 우호적인 조직문화를 가지고 있는 연구 조직에서, 이미 과학기술 지식을 많이 가지고 있고 연구 능력도 높은 외국인 과학기술자를, 한국에서 기술이 태동 또는 성장하고 있는 연구 분야에서 활용하는 것이 가장 성과가 좋다는 사실을 확인시켜 주고 있다. 국내에서 최초로 수행된 본 연구는 외국인 연구 인력의 활용 성과가 매우 높으며, 우리의 과학기술혁신시스템을 보완하는 유효한 수단으로써 외국인 연구 인력이 중요한 대안이 될 수 있음을 발견하였다. 외국인 연구 인력을 잘 활용하기 위하여 문제점 및 개선방안을 활용 환경, 연구 인력이 중요한 대안이 될 수 있음을 발견하였다. 외국인 연구 인력을 잘 활용하기 위하여 문제점 및 개선 방안을 활용 환경, 연구 인력관리. 인력 교류사업, 외국인 과학자 지원 창구 등으로 나누어서 정리하였다. 연구시설, 주거시설 등의 하드웨어적 환경에 대한 개선도 중요하지만 연구 인력의 관리 능력 제고, 인력 교류 사업의 개선, 정보 제공 등 소프트웨어적인 활용 능력을 제고하는데 정책적인 관심을 기

• Journal of Embryo Transfer
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• v.18 no.3
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• pp.203-213
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• 2003

Examination of correlation between blood compositions and economic traits is very important to improve selection accuracy and predict performance ability of Hanwoo, which may be impacted into the determination of feeding management as well as marketing places. This study was aimed to provide possible procedures of Hanwoo improvement as of early individual selection based on the phenotypic correlation between blood compositions and economic traits using 866 of Hanwoo managed at National Livestock Research Institute. Phenotypic correlation between blood compositions and economic traits was estimated for steer and bulls. BUN in steer and albumin and IGF-1 in bull were highly correlated with 24 mo of weight. Average daily gain of 21 to 24 mo was highly correlated with calcium in steer and albumin in bull. Back-fat thickness and marbling score were highly correlated with BUN in steer and bull, and meat yield index was highly correlated with calcium in steer and testosterone in bull. However, BUN, which is highly correlated with meat quality, was negatively correlated with meat yield index in steer and bull.

• Journal of Embryo Transfer
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• v.18 no.3
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• pp.215-225
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• 2003

This study was carried out to investigate the change of blood compositions by age in Hanwoo, and a total of 866 of Hanwoo, which consisted with 638 of steer and 228 of bulls, were used to measure serum concentrations. A multiple regression equation was estimated with collection age and blood composition as independent and dependent variables, respectively. Complicated regression equations for blood compositions in steer and bulls were IGF-I(cubic), calcium (linear), and IP(linear). Linear and cubic equations were fitted to testosterone in steer and creatinine in bulls, respectively. A cubic equation in steer and linear equation in bulls were fitted to HDLC. Equations of quadratic in steer and cubic in bulls were fitted to concentration of triglyceride, globulin, and A/G ratio. BUN was fitted by equations of cubic in steer and quadratic in bulls. TP and albumin were fitted by equations of quadratic in steer and linear in bulls. A cubic regression equation did not explain the change of cortisol by age in steer and bulls. A cubic regression equation did explain the change of glucose by age in steer, but not in bulls. Higher R-square values (R-SQUARE>0.1) were estimated to IGF-1, albumin, creatinine, Inorganic phosphorous(IP) and HDLC in steer, and testosterone, IGF-I, TP, albumin, glucose, creatinine, IP, and HDLC in bulls for the fitted regression equations of blood compositions. Therefore, IGF-I, albumin, creatinine, IP, and HDLC were regarded as comparatively large variation by age in steer and bulls.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.24 no.5
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• pp.343-351
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• 2012

In this study, shallow-water design waves are calculated for the return period of 10, 20, 30, and 50 years, based on the extreme value analysis of the wave measurement data at Gangneung beach. These values are compared with the results of SWAN simulation with the boundary condition of the deep-water design waves of the corresponding return periods at the Gangneung sea area provided by the Fisheries Agency (FA, 1988) and Korea Ocean Research & Development Institute (KORDI, 2005). It is found that the shallow-water wave heights at Gangneung beach calculated by the deep-water design waves were significantly less than the observation data. As the return period becomes higher, the significant wave heights obtained by the extreme value analysis becomes higher than those computed by SWAN with the deep-water design waves of the corresponding return periods. KORDI computed the hindcast wave data from January 2004 to August 2008 by WAM with a finer-grid mesh system than those of previous studies. Comparisons of the wave hindcast results with the wave observation show that the reproducibility of the winter-season storm wave was considerably improved compared to the hindcast data from 1979 to 2003. Hereafter, it is necessary to carry out hindcast wave data for the years before 2004 using WAM with the finer-grid mesh system and to supplement the deep-water design wave.

• Development and Reproduction
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• v.13 no.1
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• pp.25-33
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• 2009

The cycle of the seminiferous epithelium and development of spermatids of Apodemus speciosus peninsulae were observed using a light microscope. On the basis of developing spermatocyte and spermatid, the cycle of the seminiferous epithelium was divided into 9 stages. Type Ad spermatogonia were appeared in all stages ($I{\sim}IX$). The Ap, In, and B types of spermatogonia were appeared from stage I, II and III, and IV, respectively. In prophase of first meiosis, the leptotene spermatocytes appeared from stage V and VI, zygotene spermatocytes from stages I, II, VII, VIII, and IX, pachytene spermatocytes from stage III to VII, diplotene spermatocytes in the stage VIII, and secondary spermatocytes in stage IX. On the basis of morphology of spermatid head, developing of nuclear and acrosome and the morphological change of cytoplasm, the developing of spermatids was divided into 12 steps. Considering all the results, A. s. peninsulae displayed very similar result with A. agrarius coreae that is allied species when compare correct characters developing of spermatids with spermatogonia and appearance time of the spermatocyte. Appearance time of the same cell and number of spermatogonial generation was thought that characters of the species, and information may be useful in identifying the species.