Nematicidal and egg‐hatching inhibition activities of Kaempferia galanga rhizome‐derived materials and constituents toward root‐knot nematode (Meloidogyne incognita)

Tae‐Kyun Hong,Kym‐Na‐Ra Hwang,Jun‐Ran Kim,Young‐Joon Ahn 한국응용곤충학회 2009 한국응용곤충학회 학술대회논문집 Vol.2009 No.10

The toxicity of Kaempferia galanga rhizome materials and constituents against Meloidogyne incognita second‐stage juveniles (J2) and eggs were examined. The active principles of K. galanga rhizome were identified as the phenylpropanoids ethyl (E)‐cinnamate (EC, 1) and ethyl (E)‐p‐methoxycinnamate (EMC, 2) by spectroscopic analysis. Results were compared with those of carbofuran, fosthiazate, and metam‐sodium. In direct‐contact mortality bioassay, EC (LC50, 0.037 mg/ml) was the most toxic constituent, followed by EMC (0.041 mg/ml). EC was more effective than carbofuran (LC50, 0.092 mg/ml) but less active than fosthiazate (0.002 mg/ml). EC, egg hatch was inhibited 100, 93, and 87% at 125, 62.5, and 31.25 μg/ml, respectively. EMC caused 100, 81, and 75% inhibition of egg hatch at 125, 62.5, and 31.25 μg/ml, respectively. The inhibition of two phenylpropanoids were similar or more inhibition to that of either carbofuran or metam‐sodium but was lower than that of fosthiazate. In contact + fumigant mortality bioassay, EC and EMC treatments resulted in 86 and c 73% mortality at 0.5 and 0.125 mg/g soil, respectively. The lethality of these phenylpropanoids was almost similar to that of either carbofuran or metam‐sodium but was lower than that of fosthiazate. In vapor‐phase mortality bioassay, EC and EMC were more effective in closed container than open containers, indicating that the mode of delivery of these compounds was, in part, a result of vapor action. K. galanga rhizome‐derived materials, merit further study as potential nematicides and hatching inhibitors for the control of M. incognita populations.

Artificial Neural Network for Modeling the Tensile Properties of Ferrite-Pearlite Steels: Relative Importance of Alloying Elements and Microstructural Factors

Tae‑Woon Hong,Sang‑In Lee,Jae‑Hyeok Shim,Myoung‑Gyu Lee,Joonho Lee,Byoungchul Hwang 대한금속·재료학회 2021 METALS AND MATERIALS International Vol.27 No.10

An artificial neural network (ANN) model was developed to predict the tensile properties as a function of alloying elementand microstructural factor of ferrite-pearlite steels. The input parameters of the model were composed of alloying elements(Mn, Si, Al, Nb, Ti, and V) and microstructural factors (pearlite fraction, ferrite grain size, interlamellar spacing, and cementitethickness), while the output parameters of the model were yield strength and tensile strength. Although the ferrite-pearlitesteels have complex relationships among the alloying elements, microstructural factors, and tensile properties, the ANNmodel predictions were found to be more accurate with experimental results than the existing equation model. In the presentstudy the individual effect of input parameters on the tensile properties was quantitatively estimated with the help of theaverage index of the relative importance for alloying elements as well as microstructural factors. The ANN model attemptedfrom the metallurgical points of view is expected to be useful for designing new steels having required mechanical properties.

A Stylistic Study of "A Clean, Well-Lighted Place"

Hwang,In-Tae 한국영어학학회 2002 영어학연구 Vol.- No.14

Misorientation Characteristics at the Growth Front of Abnormally-Growing Goss Grains in Fe–3%Si Steel

Tae‑Young Kim,Tae‑Wook Na,Hyung‑Seok Shim,Yong‑Keun Ahn,Yong‑Kwon Jeong,Heung Nam Han,Nong‑Moon Hwang 대한금속·재료학회 2021 METALS AND MATERIALS International Vol.27 No.12

Penetrating morphologies at the growth front of abnormally-growing Goss grains in Fe–3%Si steel was examined in view ofthe possibility that they are the two-dimensional section of the solid-state wetting (SSW) along the triple junction line. Toobtain the statistically meaningful data, 102 penetrated grain and 204 penetrating abnormally-growing Goss grain morphologieswere examined. The misorientation angles of penetrating and penetrated grains were measured by electron backscattereddiffraction. Among the 102 examined penetrated grain boundaries, none has low misorientation angles less than 15°,whereas 17.2% of the 204 penetrating grain boundaries have low misorientation angles, and 23.5% of them have coincidencesite lattice boundaries. Besides, boundary energies of penetrating Goss grains, which were estimated from misorientationangles of the three grains in the penetrating morphology, satisfied the energetic condition for SSW along the triple junctionline. These results imply that the abnormal grain growth of Goss grains in Fe–3%Si steel occurs by the mechanism of subboundaryenhanced SSW.

Effect of Asymmetric Hot Rolling on the Texture Evolution of Fe–3%Si Steel

Tae‑Wook Na,Hyung‑Ki Park,박창수,Hyung‑Don Joo,Jong‑Tae Park,Heung Nam Han,Nong‑Moon Hwang 대한금속·재료학회 2018 METALS AND MATERIALS International Vol.24 No.6

In Fe–3%Si steel, the hot rolling process affects not only the hot rolling texture but also the primary recrystallization texture. Here, the effect of asymmetric hot rolling was studied by comparing the difference in the texture evolved between asymmetricand symmetric hot rolling. The effect of asymmetric hot rolling on the texture of primary recrystallized Fe–3%Si steel wasalso studied. The symmetric hot rolling of Fe–3%Si steel produces a rotated cube texture at the center but Goss and coppertextures near the surface. Asymmetric hot rolling tends to produce Goss and copper textures even at the center like thetexture near the surface. After primary recrystallization, the dominant texture at the center changes from {001} <210> to{111} <112> and the new texture has a higher fraction of the grains which make the low energy boundary with Goss grainsthan that of symmetric hot rolling.

Korean English Teacher's Disempowerment in English-only Classes

Sung-Sam Hwang,Hyo-Sun Seo,Tae-Young Kim 한국사회언어학회 2010 사회언어학 Vol.18 No.1

Hwang, Sung-Sam, SeD, Hyo-Sun, Kim, Tae-Young. 2010. Korean English Teacher's Disempowerment in English-only Classes: A Case Study Focusing on Korea-specific Cultural Aspects. The Sociolinguistic journal of Korea 18(1). In this case study, we have focused on the disempowerment of a Korean English teacher (KET) in English-only classrooms. Six English as a foreign language (EFL) classrooms in a Korean high school were observed and analyzed by using interpretive discourse analysis. Out of the six classes, three representative classrooms were both video- and audio-taped. The results show that the English-only classes could weaken the KETs' power via three mechanisms: (a) calling the KETs' last name for choral greetings at the beginning of the class, (b) students' group solidarity and peer pressure between classmates, and (c) the students' excessively collaborative approach to peer assistance. It is argued that the exclusive English-only instruction disempowers the KETs' status and dismantles their vocational identity. In order to remedy the current situation, within a scaffolding supported by the eclectic use of first language where necessary for effective class management, KETs are empowered and overcome constraints imposed by the limited L2 oral competence of some non-native English teachers.

師範系 體育敎育科 志望生의 一般運動能力檢査 基準値 設定에 關한 硏究

梁點紅,高基俊,黃喆文,金泰運,金重雄,白永鎬,表內淑,黃太相,徐國雄 釜山大學校 附設 體育科學硏究所 1989 體育科學硏究所 論文集 Vol.5 No.-

This study was analyzed the validity and the reliability of evaluation norm. which was used in choosing and grading events of the General Motor Ability Test. The General Motor Ability Test has been done for applicants for entrance to the department of physical education, college of education, Pusan National University. The subjects of this study were 433 applicants(men :387, women :46) for three years. They were tested in seven events : 1) 100m Dash, 2) 1500m Run(man), 800m Run (woman), 3) Throwing Hand-Ball, 4) Broad Jump, 5) Chinning(man), Flexed-Arm Hang(woman), 6) Zig-Zag Run, 7) Trunk Flexion. The results could be summerized as follows ; 1. In 100m Dash, 1500m Run, and Throwing Hand-Ball, man's average records were shown normal distribution which was inclined toward low ll grade. Therefore, the interval size of those three events must be regulated to lower. 2. Average records of Broad Jump in man were distributed into high (1) grade. So, the interval size must be adjusted to higher. 3. In Chinning, Zig-Zag Run, ad Trunk Flexion, man's average records were shawn normal distribution, and the interval size was similar to present records. 4. For woman, it was impossible to analyze correctly in all seven events because of the small number of subjects. So, it was for the sake of the reference. 5. The record of applicants for three years were operated to the variable quantity analysis. And the restults were these ; 100m Dash was F=3.0865(p<0.05), Chinning F=3.9309(p<0.05), Broad Jump F=14.7338(p<0.001), Throwing Hand-Ball F=4.9716(p<0.01), and Zig-Zag Run F=6.8297(p<0.001). Then, it was shown statistical meaningful difference in three groups. 6. In investigating the validity in choosing seven events, it was concluded that the events have been chosen reasonably. Because all events except for 100m Dash, and Zig-Zag Run in man were independent. From the analysis of the General Motor Ability Test, we could realized the necessity of regulating the standard and the interval size in several events. Then, we proposed the new evaluation norm which was suitable to present situation.

유전알고리즘을 이용한 모델추종형 퍼지제어기 설계

황기현,문경준,김문수,원태현 동의공업대학 1998 論文集 Vol.24 No.1

In this paper, a reference model following control system using a fuzzy logic controller (FLC) is proposed. A reference model whose response does not overshoot and has a fast rise time is designed. A FLC is designed to follow as close as possible the response of the reference model. The proposed design method has the robustness and the optimal tracking property under modeling error, disturbance and parameter perturbations. The proposed designing method is compared using a PD controller throughout the experiment. The effectiveness of the proposed designing method is verified through computer simulation and experiments for the second-order and the first-order reference model.

전기장이 걸린 양자우물 구조의 바닥상태 특성

황형준,권태진,최정우 慶熙大學校 材料科學技術硏究所 1999 材料科學技術硏究論集 Vol.12 No.-

We estimate the ground state energy and wavefunction in the biased quantum well structure by using the periodic boundary condition. In this calculation, we assumed that the probability of finding the particle has maximum value at the ground state energy and the amplitude of the wavefunction should not depend on a period. The obtained energy value was in good agreement with the result predicted by the complex energy method.

가솔린기관의 운전조건에 따른 배출가스 특성에 관한 硏究

黃光性,鄭鳳守,金泰圭 진주산업대학교 2000 산업과학기술연구소보 Vol.- No.7

The amount of carbon of dioxide, carbon hydroxide and nitrogen oxides produced from gasoline engine were detected by adjusting throttle valve and engine speed and increasing intaking temperature for combustion, and the results were as follows 1. The amount of CO produced decreased by intaking temperature of air increase where as it increased by increasing engine speed and closing the throttle valve. 2. The amount of HC produced decreased by increasing the intaking air, enlarging the throttle and by increasing the engine speed, but it increased carbon hydroxides more than 2400rpm at 120℃ 3. The amount of NOx produced maximized when throttle open 120˚ and speed reached 2200rpm and increased it by increasing temperature of outer air.