• Korean Chemical Engineering Research
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• v.54 no.6
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• pp.854-862
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• 2016

As the demand for a clean energy to replace fossil fuel being depleted increases, hydrogen energy is considered as a promising candidate for future energy source. Water electrolysis which produces hydrogen has high energy efficiency and stability but still has a large overpotential for oxygen evolution reaction (OER). In this study, $Co_3O_4$ catalysts with different morphology were prepared by spray pyrolysis from solutions which contain Co precursor and various organic additives (urea, sucrose, and citric acid), followed by post heat treatment. For the catalysts synthesized, X-ray diffraction (XRD) measurements were performed to identify their crystal structure. Morphology and surface shape of the catalysts were observed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Surface area and pore volume were examined by nitrogen adsortpion & desorption tests and X-ray photoelectron spectroscopy (XPS) was conducted to confirm nitrogen doping. Linear sweep voltammetry (LSV) was carried out to investigate OER activity of $Co_3O_4$ catalysts. As a result, bare-$Co_3O_4$ which has high surface area and small particle size determined by spray pyrolysis showed high activity toward OER.

• Journal of The Korean Digital Architecture Interior Association
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• v.2 no.1
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• pp.9-15
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• 2002

As architectural forms tend to be large-scaled, high-storied and complicated, use of computer for processing design information has been generalized. However, CAD use in the process of developing architectural design has been neglected greatly in the educational field of architectural field due to the surging of recognition that it may limit the essential property of architectural design. It may be resulted from the limitation of CAD system, that is, it is because of tardy speed of application development for the related areas with the lack of simplicity and clarity of flexibility to be secured on the drawing and user interface. Recent CAD systems, however, overcome such a limitation, convert into object-based design from entity-based drawing, drafting and modeling for implementing design concept of architects and it connects with internet linked to superspeed information communication network and changes process and stream of architectural design. Therefore, this study deals with utility of object based CAD system with products of Autodesk Co. and consequently obtain the following conclusions. First, it expands architect's design areas by supporting cooperative design system based on model-based architectural design and internet. Second, it reduces consumption of personal and material resources and time in the process of drawing production for improving architectural design works. Third, it can reduce the frequent design changes by improving understanding of architectural space with visualization of immediate 3D information, escaping from traditional methods to deliver design information to building owner through 2D drawing or model and perspective drawing requiring much cost and time. Fourth, it keeps exactness without omission or duplication of design information and generate and renew information of all related drawings on a drawing. Fifth, it is possible to change difficult and boring architectural design work into a pleasure owing to immediate modeling and drawing of design idea. In addition, digital drawing generated by using object-based CAD system can playa role of establishing Urban Information System to be used for protecting from building in disaster and urban disasters in connection with GIS numerical map and be used for reference of all kinds of information required fro post-management of buildings. However, what is more important is that surplus time from introduction of object-based CAD system should be used for consideration to be recognized as a good space and building built as a product of this project for comfort to urban people.

• IMMUNE NETWORK
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• v.10 no.2
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• pp.64-74
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• 2010

Background: The present study was undertaken to examine the immunological effects of pentabrominated diphenyl ether (penta-BDE) and decabrominated diphenyl ether (deca-BDE) on the immune system of the dams and the developmental immune system of the offsprings. Methods: In this study, mated female C57BL/6J mice were orally administered penta-BDE, deca-BDE or corn oil for 5 weeks, from gestational day 6 to lactational day 21. Results: The body weight of PND21 exposed to penta-BDE was significantly decreased relative to control mice, but that of post-natal day 63 (PND63) were recovered. Orally dosed dams with penta-BDE had significantly smaller absolute and relative spleen masses than control mice. Absolute and relative spleen and thymus masses of PND21 exposed to penta-BDE were significantly decreased over control. The exposure of dams and PND21 with penta-BDE reduced the number of splenocytes and thymocytes. As results of hematologic analysis, percentage WBC and percentage neutrophils increased in dams with deca-BDE. Splenic T cell proliferation in dams and PND21 exposed to penta-BDE was increased, and there were no significant difference in splenic B cell proliferation in all treatment groups. As results of flow cytometric analysis of splenocyte, percentage total T cell, Th cell and Tc cell in PND21 exposed to penta-BDE was slightly increased, and percentage macrophage in dams and PND21 exposed to deca-BDE was decreased. The ELISA results of antibody production show no significant difference in all treatment groups relative to controls. Conclusion: These results imply that PBDEs given to the dam were transferred to the offspring during gestation and lactation, and PBDEs transferred from the dam affect immune system of offspring.

• Journal of Aquaculture
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• v.20 no.3
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• pp.184-189
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• 2007

Treatment conditions for the induced diploid gynogenesis, a maternal-exclusive form of artificial parthenogenetic reproduction, were optimized in bagrid catfish (Leiocassis ussuriensis, Siluriformes). Optimal amounts of ultraviolet (UV) irradiation for the genetic inactivation of spermatozoa in bagrid catfish and Pseudobagrus fulvidraco were proven to be ranged from 3,600 to 4,800 $ergs/mm^2$ based on the examination of viability of embryos and haploid incidence. Haploid embryos were restored to diploidy by preventing the extrusion of the second polar body using cold shock treatment. Thermal treatments (4 or $6^{\circ}C$ for 30, 40 or 50 min) were carried out 3, 5 or 7 min post insemination. Best scores for embryo viability (38.6% of total eggs taken) and incidence of normal diploidy (87.9% of hatched larvae) were observed at the embryo group treated at $4^{\circ}C$ for 40 min, 5 min after insemination. Restoration of gynogenetic diploidy was confirmed based on the absence of haploid syndrome, cell size and/or nucleolar organizing region (NOR) counts.

• Journal of Plant Biotechnology
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• v.42 no.3
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• pp.135-153
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• 2015

The aromatic amino acids, which are composed of $\small{L}$-phenylalanine, $\small{L}$-tyrosine and $\small{L}$-tryptophan, are general components of protein synthesis as well as precursors for a wide range of secondary metabolites. These aromatic amino acids-derived compounds play important roles as ingredients of diverse phenolics including pigments and cell walls, and hormones like auxin and salicylic acid in plants. Moreover, they also serve as the natural products of alkaloids and glucosinolates, which have a high potential to promote human health and nutrition. The biosynthetic pathways of aromatic amino acids share a chorismate, the common intermediate, which is originated from shikimate pathway. Then, tryptophan is synthesized via anthranilate and the other phenylalanine and tyrosine are synthesized via prephenate, as intermediates. This review reports recent studies about all the enzymatic steps involved in aromatic amino acid biosynthetic pathways and their gene regulation on transcriptional/post-transcriptional levels. Furthermore, results of metabolic engineering are introduced as efforts to improve the production of the aromatic amino acids-derived secondary metabolites in plants.

• Applied Chemistry for Engineering
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• v.29 no.1
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• pp.10-17
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• 2018

POU (point of use) scrubbers were applied for the treatment of waste gases including PFCs (perfluorocompounds) exhausted from the CVD (chemical vapor deposition), etching, and cleaning processes of semiconductor and display manufacturing plant. The GWP (global warming potential) and atmosphere lifetime of PFCs are known to be a few thousands higher than that of $CO_2$, and extremely high temperature more than 3,000 K is required to thermally decompose PFCs. Therefore, POU gas scrubbers based on the thermal plasma technology were developed for the effective control of PFCs and industrial application of the technology. The thermal plasma technology encompasses the generation of powerful plasma via the optimization of the plasma torch, a highly stable power supply, and the matching technique between two components. In addition, the effective mixture of the high temperature plasma and waste gases was also necessary for the highly efficient abatement of PFCs. The purpose of this paper was to provide not only a useful technical information of the post-treatment process for the waste gas scrubbing but also a short perspective on R&D of POU plasma gas scrubbers.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.10
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• pp.1482-1488
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• 2002

The aim of this study was to explore the effects of fiber sources on gut development and bacterial activity in the gastrointestinal tract of piglets. Eighteen crossbred (Duroc${\times}$Landrace${\times}$Yorkshire) barrows were fed a basal diet based on corn plus soybean meal or similar diets in which a portion of the corn and soybean was replaced by 5% wheat bran or 5% sugar beet pulp. The results indicate that pigs fed diets containing 5% wheat bran or 5% sugar beet pulp had lower liver weights than control pigs (p<0.01). The relative weight of the pancreas in pigs fed diets containing 5% sugar beet pulp was greater than that of control pigs or pigs fed diets containing 5% wheat bran (p<0.05). The pH of the ileal digesta of pigs fed the diet containing 5% wheat bran was higher than that of control pigs or pigs fed the diet containing 5% sugar beet pulp (p<0.05). The lipase activity in the distal jejunum, proximal, and distal ileum of pigs fed the control diet was higher than that of pigs fed the diets containing 5% wheat bran or 5% sugar beet pulp (p<0.05). The concentration of volatile fatty acids anterior to the caecum was greater for the pigs fed the diet containing 5% sugar beet pulp, while the concentration of volatile fatty acids posterior to the ileum was greater for the pigs fed the diet containing 5% wheat bran. This means that sugar beet pulp increased the bacterial fermentation precaecum, while wheat bran increased the bacterial fermentation post-ileum. The concentration of bacterial nitrogen and bacterial protein/total protein in ileal digesta of pigs fed the control diet was higher (p<0.05) than that of pigs fed the diets contained either fiber source. Bacterial protein/total protein in the feces of pigs fed the diet containing 5% sugar beet pulp was higher than that of pigs fed the control diet. This means that inclusion of 5% wheat bran or sugar beet pulp in diets influenced the development of the digestive tract of piglet. The mechanism by which dietary fiber reduced specific activity of lipase needs further consideration. Dietary fiber influenced the bacterial activity in the digestive tract of piglets, sugar beet pulp increased the fermentation in the upper gastrointestinal tract, and while wheat bran increased the fermentation in the lower gastrointestinal tract.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.10
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• pp.1403-1411
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• 2002

The aims of this study were, firstly, to analyze the biochemical compositions of serum and follicular fluid (FF) from prepubertal gilts after PMSG (1,000 IU) treatment. The concentrations of total proteins, lipids, cholesterol, glucose and sex hormones (progesterone, $P_4$; estradiol-$17{\beta}$, $E_2$; testosterone, T) were measured. Secondary, the effects of porcine FF (pFF) addition (40% and 100%) in IVM media and different culture conditions [Exp. 1: mBMOC-2+20% porcine serum (PS), fresh IVM medium, filtered IVMconditioned medium, or rabbit oviducts; Exp. 2: mBMOC-2+20%PS or stepwise medium replacement procedures (SMRP) cocultured with or without cumulus cells] on the in vitro development (IVD) of porcine oocytes were also examined. Results showed that no significant differences were found in total protein levels between serum and pFF from different sizes (large, >7 mm; medium, ~5-7 mm; small, <3-5 mm) of follicles (75-85 and 49-90 mg/dl; p>0.05). Total lipid concentrations remained constant in serum (395-472 mg/dl), and reduced significantly in the pFF from large follicles (287 mg/dl) at 132 h after PMSG treatment when compared to those at other time points (441-480 mg/dl). Basal cholesterol levels in serum and pFF at 12 h were similar (153-161 mg/dl), but increased at 36 h (186-197 mg/dl). Basal P4 and E2 levels in serum (0.1 ng/ml and 5.5 pg/ml) were low, but increased from 0.34 ng/ml and 12.13 pg/ml at 24 h to 0.81 ng/ml and 61.70 pg/ml at 98 h, respectively, after PMSG treatment (p<0.05). P4 levels increased linearly in pFF from large follicles during 12 through 132 h (138-1,288 ng/ml). A similar increase was also observed in $E_2$ levels (22-730 pg/ml) before 60 h post PMSG treatment, and then dropped afterwards (730-121 pg/ml). The development of the oocytes fertilized in 40% pFF-medium was greater than that in 100% pFF-medium group without gonaodtropin addition (31% vs 10%, p<0.05). However, both were lower than those in mBMOC-2+20%PS and in rabbit oviducts (p<0.05). When cocultured with cumulus cell monolayers, a greater cleavage rate was observed in the group cultured in filtered IVM-conditioned medium than the SMRP group (36% vs 18%, p<0.05). A similar phenomenon was also observed in the culture without cumulus cell monolayers (33% vs 19%, p<0.05). It is concluded that neither the fresh IVM nor filtered IVM-conditioned medium has positive effect on the IVD of oocytes. Coculture with cumulus cell monolayers and the SMRP were not beneficial to the development of IVF pig oocytes.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.4 no.4
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• pp.43-61
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• 1981

Interest in the Quality of working life is spreading rapidly and the phrase has entered the popular vocabulary. That this should be so is probably due in large measure to changes in the values of society, nowadays accelerated as never before by the concerns and demands of younger people. But however topical the concept has become, there is very little agreement on its definition. Rather, the term appears to have become a kind of depository for a variety of sometimes contradictory meanings attributed to it by different groups. A list of all the elements it if held to cover would include availability and security of employment, adaquate income, safe and pleasant physical working conditions, reasonable hours of work, equitable treatment and democracy in the workplace, the possibility of self-development, control over one's work, a sense of pride in craftsmanship or product, wider career choices, and flexibility in matters such as the time of starting work, the number of working days in the week, Job sharing and so on altogether an array that encompasses a variety of traditional aspirations and many new ones reflecting the entry into the post industrial era. The term "quality of working life" was introduced by professor Louis E. Davis and his colleagues in the late 1960s to call attention to the prevailing and needlessly poor quality of life at the workplace. In their usage it referred to the quality of the relationship between the worker and his working environment as a whole, and was intended to emphasize the human dimension so often forgotten among the technical and economic factors in job design. Treating workers as if they were elements or cogs in the production process is not only an affront to the dignity of human life, but is also a serious underestimation of the human capabilities needed to operate more advanced technologies. When tasks demand high levels of vigilence, technical problem-solving skills, self initiated behavior, and social and communication skills. it is imperative that our concepts of man be of requisite complexity. Our aim is not just to protect the worker's life and health but to give them an informal interest in their job and opportunity to express their views and exercise control over everything that affects their working life. Certainly, so far as his work is concerned, a man must feel better protected but he must also have a greater feeling of freedom and responsibility. Something parallel but wholly different if happening in Europe, industrial democracy. What has happened in Europe has been discrete, fixed, finalized, and legalized. Those developing centuries driving toward industrialization like R.O.K, shall have to bear in mind the human complexity in processing and designing the work and its environment. Increasing attention is needed to the contradiction between autocratic rule at the workplace and democratic rights in society.n society.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.48 no.2
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• pp.127-133
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• 2003

The purpose of this study is to investigate the positive or negative effects of 5-aminolevulinic acid(ALA) on the growth of several crops and weeds, by applying a seed soaking treatment, foliar treatment, and application timing, while comparing biological activity between ALA produced by chemical synthesis (Synthetic-ALA) and extracellularly-accumulated ALA by overexpressing the hemeA gene isolated from Bradyrhizobium japonicum(Bio-ALA). Seed soaking treatment of ALA in barley (five cultivars) and wheat (five cultivars) had not shown positive effects at lower concentrations, 0.05 to 0.5 mM as well as negative effects at higher concentrations, 1 to 30 mM. In rice, there also was no positive effect by seed soaking treatment of ALA at lower concentrations, although the rice became damaged by an application of 5 and 10 mM ALA. Growth in barley cultivars, Ganghossalbori, Naehanssalbori, Songhakbori, Saessalbori, and Daehossalbori were increased up to 14%, 19-51 %, 17-64%, 18-23%, and 22-38% by ALA foliar application at lower concentrations, 0.05 to 0.5 mM, respectively. On the other hand, the growth in barley cultivars was inhibited by ALA foliar application at higher concentrations. Barley responded more positively to ALA foliar application than wheat and rice. The growth stimulation caused by ALA seed soaking treatment was less than by ALA foliar treatment. ALA treatment at the 1.5-leaf stage increased growth of barley by 19-58%, while pretreatment to seeds, post-emergence treatment at 3 days after seeding, 3-leaf stages, and 5-leaf stages had not shown positive effects. Thus, the positive effects of ALA on barley were dependent greatly upon the timing of application and its concentration. Monocots weeds were more sensitive to ALA foliar treatment than dicotyledonous weeds. A monocot weed, Setaria viridis L. was the most susceptible plant to ALA while a dicotyledonous weed, Plantago asiatica L. was the most tolerant. No significant difference in biological activity between bio-ALA and synthetic ALA on barley, wheat, rice, and weed, Ixeris dentate tested was observed. Thus, ALA produced by microorganisms would be a potent substance to be used effectively in agricultural production.