• Journal of Sericultural and Entomological Science
• /
• v.46 no.2
• /
• pp.58-64
• /
• 2004

The current study was performed to clarify the pupation disorder symptoms in silkworm which herbicide, molinate has been regarded as a causal origin. Molinate residues in mulberry leaves was monitored in major rearing area of silkworm; Yeacheon, Sangju and Namwon. Detected range of the molinate in mulberry leaves was 0.002 to 0.013 mg/kg and detection frequency was 30.0 to 81.8%. Molinate concentration in the air of mulberry tree growing area was $0.004\;{\mu}g/m^3$. Water diluted solution of molinate at the concentration of 1, 10, 100 mg/l gave no abnormal symptoms in silkworm irrespective of spraying to silkworm or spiking to diet. Exposing the silkworm to the air containing 250, 2,500, and $10,000\;{\mu}g/m^3$ also revealed no abnormal symptom. These results illustrated that the abnormal growth of silkworm encountered in the field was not caused by pesticide contamination.

• Journal of Sericultural and Entomological Science
• /
• v.38 no.2
• /
• pp.93-99
• /
• 1996

By treatment(dropping) of 0.1~0.4% colchicine solution on the sprouts of winter buds of hard wood cutting slips for 4~5 days, two lines of artificial autotetraploids from Yongchonppong and one line from Yeongbyonppong were bred and the important cultivative characteristics of those new lines were as follows. The greentip sprouting stage of the new bred lines in spring season is later than the parental varieties by two days, but growth speed of the new lines after sprouting was faster than that of the parental varieties reaching the same level development with the parental varieties at the fifth leaf sprouting stage to be mid varieties same as the origins. The leaf shape of the new bred lines was wide round and the petioloes were long and thick. The thickness of leaf was thicker than the parental varieties by 17-33% and single leaf weight was heavy. The leaf area weight increased by 21-31% and the content of chlorophyll was also higher by 11-33%. With all the characteristics, the new breds produced good quality of leaves. The length and number of branches were shorter and less, respectively, than the parental varieties, but the internode length was either same or longer than the parents. Looking at the characteristics, the constitution of shoots was slightly inferior to the parental varieties. The cold hardness expressed by the death top rate of Sawonppong 23 and Sawonppong 24 was same level as that of Yongchonppong, but Sawonppong 25 was stronger than Yeongbyonppong in it with a high infection rate of dwarf disease. The productivity was lower than the parental varieties, but young shoot rate to shoot and branch and the ratio of leaf to young shoot were higher than the parental varieties. The fertility of Sawonppong 23 and Sawonppong 24 was comparatively high with 62% of cross success, but that of Sawonppong 25 was low with 23.9% of cross success.

• Applied Biological Chemistry
• /
• v.27 no.1
• /
• pp.40-44
• /
• 1984

Experiments on the GA production ability by ectomycorrhizal fungus, Pisolithus tinctorius was carried out to investigate specific physiological phenomena of growth increase in host plants by formation of mycorrhizae, The culture extract of P. tinctorius was purified by solvent fractionation, sephadex LH-20 chromatography, silica gel partition chromatography and TLC, successively. GA activities in the purified GA fractions were monitored by micro-drop bioassay using dwarf rice seedlings, 'Tan-ginbozu'. $30{\sim}60%$ EtOAc election fractions of silica gel pardon chromatography and the zone of Rf $0.1{\sim}0.4,\;0.6{\sim}0.8$ of TLC exhibited the GA-like activities. The GA activities were increased with the more treated amount of culture extracts. This activity in 100ml of culture solution was equivalent to 0.1ng of $GA_3$.

• Proceedings of the Korean Magnestics Society Conference
• /
• 2011.06a
• /
• pp.7-8
• /
• 2011

Basically, the lattice mismatch between film and substrate can make those BiFeO3(BFO) films distorted with strain structure. BFO phase can be stabilized on LaAlO3(LAO) represents the example of a multiferroic with giant axial ratio. Its crystal structure is not strictly tetragonal, but tetragonal with a slight monoclinic distortion and related to the rotation of the oxygen octahedra. In this study, we show that phases with a tetragonal-like epitaxial BFO films can indeed be ferroelectric and also can be stabilized via epitaxial growth onto LAO. Recent reports on epitaxial BFO films show that the crystal structure changes from nearly rhombohedral ("R-like") to nearly tetragonal("T-like") at strains exceeding approximately -4.5%, with the "T-like" structure being characterized by a highly enhanced c/a ratio. While both the "R-like" and the "T-like" phases are monoclinic, our detailed x-ray diffraction results reveal asymmetry change from MA and MC type, respectively. By applying additional strain or by modifying the unit cell volume of the film by substituting Ba for Bi, the monoclinic distortion in the "T-like" MC phase is reduced, i.e. the system approaches a true tetragonal symmetry. There are two different M-H loops for $Bi_{1-x}Ba_xFeO_{3-{\delta}}$(BBFO) and BFO films on SrTiO3(STO) & LAO substrates. Along with the ferroelectric characterization, these magnetic data indicate that the BFO phase stabilized on LAO represents the first example of a multiferroic with giant axial ratio. However, there is a significant difference between this phase and other predicted ferroelectrics with a giant axial ratio: its crystal structure is not strictly tetragonal, but tetragonal with a slight monoclinic distortion. Therefore, in going from bulk to highly-strained films, a phase sequence of rhombohedral(R)-to-monoclinic ["R-like" MA-to-monoclinic, "T-like" MC-to-tetragonal (T)] is observed. This sequence is otherwise seen only near morphotropic phase boundaries in lead-based solid-solution perovskites (i.e. near a compositionally induced phase instability), where it can be controlled by electric field, temperature, or composition. Our results show that this evolution can occur in a lead-free, stoichiometric material and can be induced by stress alone. Those major results are summarized as follows ; 1) Ba-doping increases the unit cell volume, 2) BBFO on LAO can be fully strained up to x=0.08 as a strain limit (Fig. 1), 3) P(E) & M(H) properties can be tuned by the variation of composition, strain, and film thickness.

• Journal of Radiation Protection and Research
• /
• v.23 no.4
• /
• pp.219-227
• /
• 1998

A solution containing $^{85}Sr$, $^{103}Ru$ and $^{134}Cs$ was applied to Chinese cabbage in a greenhouse via foliar spraying at 5 different times during its growth. Interception of the applied activity by plant showed no difference among radionuclides and increased with decreasing time interval between application and harvest. The maximum interception factor observed was 0.87. Percentages of the intercepted activity remaining in the whole leaves at harvest varied $16{\sim}58%$ for $^{85}Sr$, $15{\sim}73%$ for $^{103}Ru$ and $33{\sim}64%$ for $^{134}Cs$, with application time and those for the inner leaves (without 6 outmost leaves) varied $2{\sim}35%$, $0.4{\sim}46%$ and $14{\sim}40%$, respectively. It was demonstrated that rain plays an important role in weathering loss of the activity. Tying the upper end of the plant prior to the last application lowered interception and remaining activity in the inner leaves by factors of $3{\sim}4$. Present results can be referred to in predicting the radionuclide concentration in Chinese cabbage and deciding counter-measures at the time of an accidental release from the nuclear installation.

• KDI Journal of Economic Policy
• /
• v.12 no.4
• /
• pp.3-20
• /
• 1990

The multisector model is designed to analyze and forecast structural change in industrial output, employment, capital and relative price as well as macroeconomic change in aggregate income, interest rate, etc. This model has 25 industrial sectors, containing about 1,300 equations. Therefore, this model is characterized by detailed structural disaggregation at the sectoral level. Individual industries are based on many of the economic relationships in the model. This is what distinguishes a multisector model from a macroeconomic model. Each industry is a behavioral agent in the model for industrial investment, employment, prices, wages, and intermediate demand. The strength of the model lies in the simulating the interactions between different industries. The result of its simulation will be introduced in the next paper. In this paper, we only introduce the structure of the multisector model and the coefficients of the equations. The multisector model is a dynamic model-that is, it solves year by year into the future using its own solutions for earlier years. The development of a dynamic, year-by-year solution allows us to combine the change in structure with a consideration of the dynamic adjustment required. These dynamics have obvious advantages in the use of the multisector model for industrial planning. The multisector model is a medium-term and long-term model. Whereas a short-term model can taken the labor supply and capital stock as given, a long-term model must acknowledge that these are determined endogenously. Changes in the medium-term can be analyzed in the context of long-term structural changes. The structure of this model can be summarized as follow. The difference in domestic and world prices affects industrial structure and the pattern of international trade; domestic output and factor price affect factor demand; factor demand and factor price affect industrial income; industrial income and relative price affect industrial consumption. Technical progress, as measured in terms of total factor productivity and relative price affect input-output coefficients; input-output coefficients and relative price determine the industrial input cost; input cost and import price determine domestic price. The differences in productivity and wage growth among different industries affect the relative price.

• 한국초등상담교육학회:학술대회논문집
• /
• 2004.01a
• /
• pp.137-168
• /
• 2004

The purpose of this study is to find the effect of group counseling program based on reality therapy that is developed by researcher and to investigate whether the program can decrease the academic stress of elementary school students. For this study, firstly a framework for academic stress decrease programs is established and a program is developed in accordance with the framework. Secondly, in order to verify the effect of the program, both quantitative and qualitative methods were applied to 6th grade students through a academic stress test. Experimental group and control group is composed of 18 students, each. During a two month-experimental period, group counseling program based on reality therapy was implemented to the experimental group for 10 sessions but not to the control group. The program included nicknaming, recreation activities to promote friendliness among participants and other various activities to decrease the academic stress. The results of the quantitative and statistical research are as follows: First, group counseling program based on reality therapy is effective to decrease of elementary school students' academic stress. Second, sub factor(such as perceptions of academic stress cause, symptoms of academic stress)of academic stress is significantly decreased in experimental group. But no significant difference is found in control group. Third, for some sub factor(career, friend-relationship, house-environment, behavior-symptom), an independent-sample test and a paired-sample test showed different results: the paired-sample test showed no significant differences in experimental group while the independent-sample test showed significant decrease of academic stress. The results of the qualitative research based on student commentaries on the program is as follows: First, experimental group students report that the program based on reality therapy was effective to decrease of academic stress. Second, experimental group students' commentaries shows that students could remember the WDEP, 'act' factor and acquire the solution of academic stress. Third, for a group counseling, students reported the interest about positive feedback, searching on themselves, growth of human-relationship. This means that the program developed on this study is suitable for group counseling program. In conclusion, this study proves that group counseling program based on reality therapy is effective to decrease of elementary school students' academic stress by increasing individual internal-control. Therefore, it is necessary that we should develop and apply similar program to elementary school students in other to decrease students' academic stress. school students in other to decrease students' academic stress.

• Korean Journal of Construction Engineering and Management
• /
• v.11 no.6
• /
• pp.111-121
• /
• 2010

As the customer's interest for sidewalk block in the street or apartment complex is increasing, the materials of block which had been a concrete block exclusively are varied to clay paver, native rock and wood etc. Especially, the sales volume of clay paver which is environment-friendly and ergonomic is dramatically increasing every year with two digits growth rate, however, many problems like "Edge Cracking" "Freezing Breakage" "Bending Breakage" "Joint Gap" are happening frequently within a couple of hours after installation due to the durabilities. Because of the characteristics of Ceramic products, clay pavers are very easy to be broken when they are bumped against each other. In addition, they are relatively fragile by a freezing expansion breakage when exposed to water due to hydrophilic property as well as the intensity and absorptance of the products are varied with small difference from the production process such as production equipment and process control. Therefore, it costs a lot of money to repair the breakdown unless production and installation is carried out according to the strict criteria of the quality control. In this study, the symptoms of breakdown frequently happened in clay paver are classified by each type and finally the solution for this problem in the production of brick, installation and criteria of quality control through compressive strength and absorptance test is suggested.

• Journal of the Korean Ceramic Society
• /
• v.41 no.2
• /
• pp.136-142
• /
• 2004

A homogeneous and stable ZnO sol was prepared by dissolving the zinc acetate dihydrate(Zn(CH$_3$COO)$_2$$.$2H$_2$O) in solution of isopropanol((CH$_3$)$_2$$.$CHOH) and monoethanolamine(MEA:H$_2$NCH$_2$CH$_2$OH). ZnO thin films were prepared by sol-gel spin-coating method and investigated for c-axis preferred orientation and physical properties with preheating temperature. The c-axis growth had a difference as increaing preheating temperature. ZnO thin film preheated at 275$^{\circ}C$ and post-heated at 650$^{\circ}C$ was highly oriented along the (002) plane. After preheating at 200∼300$^{\circ}C$ and post-heating at 650$^{\circ}C$, the transmittance of ZnO thin films by UV-vis. measurement was over 85% in visible range and exhibited absorption edges at about 370 nm. The optical band gap energy was obtained about 3.22 eV, The photoluminescence emission characteristics of ZnO thin film preheated at 275$^{\circ}C$ and post-heated at 650$^{\circ}C$ was found to orange emission(620 nm, 2.0 eV) by PL measurement, which revealed the possibility for application of inorganic photoluminescence device.

• Industry Promotion Research
• /
• v.5 no.1
• /
• pp.137-147
• /
• 2020

Social co-operatives, which are working positively to realize the economic and social purpose of being carried out directly through products and services producing the public interest, are steadily expanding under the public interest mission of social co-operatives. It has important theoretical and practical significance to study the model of social co-operatives tailored to the local situation in Korea based on international experience. This study looks at the international status of social co-operatives, international cases, and puts forward problems and suggestions centering on cases of advanced countries. It sought to find a solution to what society required only by solving the problems necessary for sustainable economic growth. In order to achieve the objectives of this study, the social cooperatives of advanced countries, such as Italy, Canada, and France, were organized, compared and analyzed. The study found that the implications of co-operatives in Italy, France and Canada are as follows. First, it is needed to adhere to the principles of co-operatives in pending issues such as social problems and employment and jobs in the community. Second, it is necessary to establish a supportive financial system for the cooperative's initial stability and sustainability. Third, the ecosystem of co-operatives should be formed to support and foster legal systems and network organizations.