It is highly challenging to measure the efficiency of electric vehicle charging stations (EVCSs) because factors affecting operational characteristics of EVCSs are time-varying in practice. For the efficiency measurement, environmental factors around the EVCSs can be considered because such factors affect charging behaviors of electric vehicle drivers, resulting in variations of accessibility and attractiveness for the EVCSs. Considering dynamics of the factors, this paper examines the technical efficiency of 622 electric vehicle charging stations in Seoul using data envelopment analysis (DEA). The DEA is formulated as a multi-period output-oriented constant return to scale model. Five inputs including floating population, number of nearby EVCSs, average distance of nearby EVCSs, traffic volume and traffic congestion are considered and the charging frequency of EVCSs is used as the output. The result of efficiency measurement shows that not many EVCSs has most of charging demand at certain periods of time, while the others are facing with anemic charging demand. Tobit regression analyses show that the traffic congestion negatively affects the efficiency of EVCSs, while the traffic volume and the number of nearby EVCSs are positive factors improving the efficiency around EVCSs. We draw some notable characteristics of efficient EVCSs by comparing means of the inputs related to the groups classified by K-means clustering algorithm. This analysis presents that efficient EVCSs can be generally characterized with the high number of nearby EVCSs and low level of the traffic congestion.

Evaluating the operational efficiency of electric vehicle charging stations (EVCSs) is important to understand charging network evolution and the charging behavior of electric vehicle users. However, aggregation of efficiency performance metrics poses a significant challenge to practitioners and researchers. In general, the operational efficiency of EVCSs can be measured as a complicated function of various factors with multiple criteria. Such a complex aspect of managing EVCSs becomes one of the challenging issues to measure their operational efficiency. Considering the difficulty in the efficiency measurement, this paper suggests a way to measure the operational efficiency of EVCSs based on data envelopment analysis (DEA). The DEA model is formulated as constant returns of output-oriented model with five types of inputs, four of them are the numbers of floating population and nearby charging stations, distance of nearby charging stations and traffic volume as desirable inputs and the other is the traffic speed in congestion as undesirable one. Meanwhile, the output is given by the charging frequency of EVCSs in a day. Using real-world data obtained from reliable sources, we suggest operational efficiencies of EVCSs in Seoul and discuss implications on the development of electric vehicle charging network. The result of efficiency measurement shows that most of EVCSs in Seoul are inefficient, while some districts (Nowon-gu, Dongdaemun-gu, Dongjak-gu, Songpa-gu, Guro-gu) have relatively more efficient EVCSs than the others.

Recently, improvement of eggshell hygiene has emerged as an important issue in food industry. Various studies have continued to examine methods for controlling egg-borne pathogen, and among such methods, for table eggs, washing (with UV irradiation) is the most commonly used method. However, this method was not sufficient to control egg microbial contamination. Therefore, the purpose of this study was to verify whether it is appropriate to use ClO2 gas, which has been proven safe in this experiment model, as an alternative to the conventional washing (with UV irradiation) method. As a result, we have identified a range of optimal effectiveness in response to exposure concentrations and time of ClO2 gas. Through experimental models that reflect differences in farm size, a microbial reduction effect of approximately >2 log CFU/eggshell was achieved at 40ppm/8h for small farms, and 160ppm/30min for large farms, indicating greater effectiveness than the conventional method. However, in large-scale experiment, when bulk eggs were stacked and exposed to ClO2 gas, eggs in the depths showed a lower effect by approximately 0.8~1.5 log CFU/eggshell, as compared to the eggs in the upper section. For further study, if technical improvements are achieved in the future studies allowing the gas to better penetrate the depths of stacked eggs, it will be a model that can be more useful to the field.

For air express service providers offering various express delivery services such as overnight delivery and next-business day delivery services, establishing quickly cargo loading plans is one of important issues owing to the characteristics of air express business, i.e., a short amount of time is available to complete all cargo loading operations before flight departure after receiving air express containers, pallets and bulks. On the other hand, one of major concerns in the air cargo loading planning is to make a plan that insures the stability of an aircraft to avoid take-off, flight, and landing accidents. To this end, this paper considers an air cargo loading planning problem, which is the problem of determining locations in the aircraft cargo space where air containers, pallets and bulks to be loaded while insuring the aircraft stability, motivated from DHL and Air Hong Kong. The objective of the problem is to maximize the total revenue gained from loading air express containers, pallets and bulks. To solve the problem, this paper suggests a simulated annealing algorithm to overcome impracticality of the integer programming model developed by a previous study requiring excessive computation time. The results of computational experiments show that the heuristic algorithm is a viable tool for establishing express cargo loading plans as giving robust and good solutions in a short amount of computation time. Scenario analyses are performed to investigate the effect of the current activities of air express carriers on the revenue change and to draw practical implications for air express service providers.

In order to investigate the effects of antioxidants on the culture of mouse preantral follicles in vitro, we examined the effects of taurine, glutathione and catalase on their growth and maturation. Addition of taurine was not effective on the survival of preantral follicles. However, metaphase II rates of oocytes within preantral follicles were signifi-cantly higher in 1 mM treated group than in control and 10 mM treated group (p<0.05). Glutathione did not improved the rates of survival and metaphase II oocytes. However, metaphase II rates of oocytes progressively decreased with increasing glutathione concentration. Catalase also showed that the rates of survival and metaphase II oocytes pro-gressively decreased with increasing concentration. Especially, all of preantral follicles cultured in medium containing 100 IU/ml catalase were degenerated. These results suggest that low concentraion of taurine, as an antioxidant, have positive effect on the culture of mouse preantral follicles in vitro.

The purpose of this study was to assess follicular viability and competence through in vitro culture of preantral follicles isolated from vitrified mouse whole ovaries. Mouse preantral follicles were enzymatically isolated from vitrified-warmed and fresh ovaries and cultured for 10 days followed by in vitro oocyte maturation. In vitro matured oocytes were fertilized and cultured to the blastocyst stage. Five minutes pre-exposure to vitrification solution of whole ovaries had significantly higher (p<0.05) oocyte survival and maturation rates than between 10 min exposure groups. Oocyte diameter was significantly smaller (p<0.05) in the 5 and 10 min exposure groups (69.4±2.8 and 67.8±3.1) when compared to that of control group (71.7±2.1). There was no statistical significant difference in blastocyst development rates between vitrification group (8.6%) and the fresh control group (12.0%). The mean number of cells per blastocyst was significantly lower (p<0.05) in the vitrification group (41.9±20.2) than in the fresh control group (55.1±22.5). The results show that mouse oocytes within preantral follicles isolated from the vitrified whole ovaries can achieve full maturation, normal fertilization and embryo development.

This study was conducted to investigate an effective recipient oocyte and culture system for producing of Hanwoo (Korean native cattle) somatic cell nuclear transfer (SCNT) embryos. Hanwoo ear skin fibroblasts were used as donor cells. In vitro matured Hanwoo or Holstein oocytes were enucleated, and single donor cells were transferred into the perivitelline space of the enucleated oocytes. The couplets were subsequently fused and activated. The reconstructed embryos were cultured in a conventional or sequential culture system. In the former, embryos were cultured in CR2aa medium for eight days; in the latter, embryos were cultured in modified CR2aa-A (mCR2-A) for three days and then further cultured in modified CR2aa-B (mCR2-B) for five days. In the experiment with the recipient oocyte, the rate of embryo development to the blastocyst stage was significantly (p<0.05) higher in Hanwoo recipient oocytes than in Holstein ones (48.8% vs 38.9%). BIastocysts derived from Hanwoo recipient oocytes contained significantly (p<0.05) higher numbers of total cells than those derived from Holstein recipient oocytes (156.0+-68.2 vs 134.7+-54.8)). There was no difference in the mean proportion of apoptotic cells in blastocysts between the sources of recipient oocytes. In the experiment with the embryo culture system, the blastocyst rate was somewhat higher in sequential system than in conventional system (50.0% vs 43.5%), though there was no significant difference. The numbers of total (160.0+-69.0 vs 156.7+-68.4) and apoptotic cells (14.0+-10.4 vs 11.8+-6.4)) were not different between the culture systems. In conclusion, the present study demonstrated that Hanwoo recipient oocytes and the sequential culture system were more effective in supporting the production of Hanwoo SCNT embryos.

The aim of this study was to examine more effective cryoprotectant for the cryopreservation of mouse preantral follicles. Enzymetically isolated preantral follicles from 12-day-old mice were cryopreserved by a slow freezing protocol with 1.5 M propanediol (PROH), dimethyl sulphoxide (DMSO) or glycerol (GLY) and then grown and matured in vitro for 11 days after thawing. The survival of preantral follicles immediately after freezing and thawing was not different among the PROH (68.2%), DMSO (72.4%) and GLY (72.1%). After grown and matured in vitro, the rates of survival and metaphase II oocytes were 54.9% and 36.6% for PROH which was significantly higher rates (p<0.05) compared with the rates obtained from DMSO (16.9% and 9.0%) and GLY (16.3% and 7.5%). The diameter of metaphase II oocytes from pre antral follicles frozen in PROH (67.4+-1.8 um) was significantly (p<0.05) smaller than that of the fresh preantral follicles (69.1+-2.3 um). The results from the present study revealed that PROH is more suitable cryoprotectant for the cryopreservation of mouse preantral follicles.

For the practical feasibility of lactic acid (LA) fermentation process, a continuous operation using mixed culture and the use of cheap and non-food raw materials are essential. In this study, a continuous LA fermentation of food waste was attempted using indigenous mixed culture. During the operation, temperature was gradually increased from 35℃ to 55℃, with showing the highest performance at 50℃. At 35-45℃, other organic acids such as acetic acid and butyric acid were also observed. At 50℃ and HRT 1.0 d, both LA production yield and its productivity were maximized to 1.8 mol LA/mol hexoseadded and 1.4 g LA/L/hr, respectively. A pyrosequencing result showed that Lactobacillus amylolyticus was the predominant species performing LA fermentation of food waste. The combined process of nanofiltration and water-splitting electrodialysis could recover highly purified LA from the fermentation broth by removing 95% of mineral ions and 77% of ammonium and glucose.

The present study researched morphological characteristics and analyzed the genetic diversity by using RAPD in Calanthe species, native plant in Jeju, Korea. Twenty-six samples were selected by flower color, and 19 horticultural traits were investigated to study morphological characteristics. The C. discolor had the smallest leaf, the length and width of dorsal sepal, lateral sepal, petal, central lip, lateral lip, and flower stalk length were shortest and/or smallest except the spur and ovary length in Calanthe species, but those of Calanthe discolor for. sieboldii (Dence.) Ohwi (Calanthe discolor for. sieboldii) were the largest and/or biggest, and those of variants were the intermediate between C. discolor and C. discolor for. sieboldii, but spur length was the longest in C. discolor, the shortest in C. discolor for. sieboldii, and intermediate in the variants. Ovary length in C. discolor was shortest and C. discolor for. sieboldii and variants were similar with each other. The flower colors of C. discolor were brownish red, the value of CIE Lab was between 40 and 50. The flower color of C. discolor for. sieboldii was yellowish; the value of CIE Lab was between 110 and 130. And variants had various colors between 50 and 70 in the value of CIE Lab. After analyzing multiple band patterns of PCR products, 154 bands were selected as polymorphic RAPD markers. The analysis of Genetic distance of Calanthe species using RAPD showed that C. discolor and C. discolor for. sieboldii are more distant from each other than variants, and demonstrated the fact that genetic position of variants is between the other two species.

Buckwheat is one of the traditional crops and has become a renewed target of interest or a popular crop as a healthy foodstuff, because it is a good source of cereal protein which is rich with essential amino acids. However, what is critical to our health is that buckwheat contains proteins which cause a allergy. Buckwheat allergy resulting from ingestion is caused by the storage proteins in the grain with molecular weights ranging from 15, 22, 35, 39 and 50 kDa proteins of the inner fractions to low, and there were clear differences in the protein compositions between the inner and outer buckwheat flour fractions. A major allergenic protein of buckwheat is Fag e 1 with molecular weight 22 kDa (BW22KD). Buckwheat allergy is an immunoglobulin E (IgE)-mediated hypersensitive response capable of causing anaphylactic shock. Buckwheat seeds were dissected to endosperm and embryo. From each fraction we extracted proteins and analyzed extracts by SDS-PAGE and 2-DE. On electrophoregrams of endosperm proteins, 6 intense bands were detected. The most intense corresponded to molecular weights ranging from 54 to 65 kDa. These proteins have been reported not to be allergenic. We show here that the allergenic buckwheat seed proteins are found only among embryo proteins. No allergenic proteins were found in the buckwheat endosperm. The results presented here lead to the proposal that patients with hypersensitivity to buckwheat flour should use only fine flour from buckwheat endosperm, as this fraction contains no allergenic proteins. At present, specific protein spots will be selected and in-gel digested for MALDI-TOF-TOF/MS analysis.