• Safety and Health at Work
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• v.14 no.4
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• pp.488-491
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• 2023

This study aims to ascertain occupations potentially at greatest risk of exposure to SARS-CoV-2 based on pre-lockdown working conditions in France. We combined two French population-based surveys documenting workplace exposures to infectious agents, face-to-face contact with the public, and working with colleagues just before the pandemic. Then, for each 87-level standard French occupational grouping, we estimated the number and percentage of the French working population reporting these occupational exposure factors, by gender, using survey weights. As much as 40% (11 million) of all workers reported at least two exposure factors. Most of the workers concerned were in the healthcare sector. However, army/police officers, firefighters, hairdressers, teachers, cultural/sports professionals, and some manual workers were also exposed. Women were overrepresented in certain occupations with potentially higher risks of exposure such as home caregivers, childminders, and hairdressers. Our gender-stratified matrix can be used to assign prelockdown work-related exposures to cohorts implemented during the pandemic.

• Journal of Intelligence and Information Systems
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• v.21 no.2
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• pp.1-18
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• 2015

Collaborative filtering(CF) algorithm has been popularly used for recommender systems in both academic and practical applications. A general CF system compares users based on how similar they are, and creates recommendation results with the items favored by other people with similar tastes. Thus, it is very important for CF to measure the similarities between users because the recommendation quality depends on it. In most cases, users' explicit numeric ratings of items(i.e. quantitative information) have only been used to calculate the similarities between users in CF. However, several studies indicated that qualitative information such as user's reviews on the items may contribute to measure these similarities more accurately. Considering that a lot of people are likely to share their honest opinion on the items they purchased recently due to the advent of the Web 2.0, user's reviews can be regarded as the informative source for identifying user's preference with accuracy. Under this background, this study proposes a new hybrid recommender system that combines with users' review mining. Our proposed system is based on conventional memory-based CF, but it is designed to use both user's numeric ratings and his/her text reviews on the items when calculating similarities between users. In specific, our system creates not only user-item rating matrix, but also user-item review term matrix. Then, it calculates rating similarity and review similarity from each matrix, and calculates the final user-to-user similarity based on these two similarities(i.e. rating and review similarities). As the methods for calculating review similarity between users, we proposed two alternatives - one is to use the frequency of the commonly used terms, and the other one is to use the sum of the importance weights of the commonly used terms in users' review. In the case of the importance weights of terms, we proposed the use of average TF-IDF(Term Frequency - Inverse Document Frequency) weights. To validate the applicability of the proposed system, we applied it to the implementation of a recommender system for smartphone applications (hereafter, app). At present, over a million apps are offered in each app stores operated by Google and Apple. Due to this information overload, users have difficulty in selecting proper apps that they really want. Furthermore, app store operators like Google and Apple have cumulated huge amount of users' reviews on apps until now. Thus, we chose smartphone app stores as the application domain of our system. In order to collect the experimental data set, we built and operated a Web-based data collection system for about two weeks. As a result, we could obtain 1,246 valid responses(ratings and reviews) from 78 users. The experimental system was implemented using Microsoft Visual Basic for Applications(VBA) and SAS Text Miner. And, to avoid distortion due to human intervention, we did not adopt any refining works by human during the user's review mining process. To examine the effectiveness of the proposed system, we compared its performance to the performance of conventional CF system. The performances of recommender systems were evaluated by using average MAE(mean absolute error). The experimental results showed that our proposed system(MAE = 0.7867 ~ 0.7881) slightly outperformed a conventional CF system(MAE = 0.7939). Also, they showed that the calculation of review similarity between users based on the TF-IDF weights(MAE = 0.7867) leaded to better recommendation accuracy than the calculation based on the frequency of the commonly used terms in reviews(MAE = 0.7881). The results from paired samples t-test presented that our proposed system with review similarity calculation using the frequency of the commonly used terms outperformed conventional CF system with 10% statistical significance level. Our study sheds a light on the application of users' review information for facilitating electronic commerce by recommending proper items to users.

• 한국생물공학회:학술대회논문집
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• 2005.04a
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• pp.35-35
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• 2005

Recombinant human $interferon-{\beta}-1a(rIFN-{\beta})$ is a single glycosylated protein (at N80, 1N) with anti-viral activity. However, present drugs have a relatively short serum half-life of $rIFN-{\beta}$, thus patients suffer from frequent $infections.^{1)}$ To improve its half-life, eight glycosylation analogs were prepared, which have additional N-linked glycosylation consensus sequences (N-X-T/S) within the $IFN-{\beta}$ molecule and/or at C-terminal. Each $rIFN-{\beta}$ analog was examined for the presence of additional N-linked glycosylation and the maintenance of anti-viral activity in CHO cells. The molecular weights of five analogs were not changed. However, two analogs, R27T within $rIFN-{\beta}$ (27 kDa, 2N) and GNITVNITV at C-terminal (29kDa, 2N), showed a clear increase in molecular weights, compared to native $rIFN-{\beta}$ (23 kDa, 1N). And another combined analog of R27T+GNITVNITV showed increased molecular weight (33 kDa, 3N). It was confimed that the molecular weight increment of analogs was caued by the N-linked glycosylation with the treatment of N-glycansae. In the case of anti-viral activity, the analog GNITVNITV showed a reduction in activity compared to native $IFN-{\beta}$, whereas the analogs R27T and R27T+GNITVNITV were found to have distinctly increased activities. Pharmacokinetic study in rats also disclosed that the analogs R27T and R27T+GNITVNITV had 2 3 fold increased serum half-life, respectively. In conclusion, the addition of N-linked glycosylation in $rIFN-{\beta}$ increased serum half-life, thereby its less frequent administration will be expected.

• Toxicological Research
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• v.23 no.4
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• pp.391-403
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• 2007

The study was conducted to assess the repeated dose and reproduction and developmental toxicities of acetanilide, an intermediate for drug production, as a part of OECD Screening Information Data Set (SIDS) program. The test agent was administered by gavage at dose levels of 0, 22, 67, 200 and 600 mg/kg to Sprague-Dawley rats (12/group/sex) during pre-mating and mating period for males(up to 30 days) and females and pregnancy and early lactation period for females (up to 39-50 days). At 22 mg/kg, decreases in HGB, HCT (males) and MCHC (females), hyperplasia of spleen red pulp, hyperplasia of femur bone marrow (both sexes) were observed. At 67 mg/kg, salivation (males), reduced food consumption (both sexes), decreases in RBC, HGB, HCT and MCHC (males), increases in MCV (males) and spleen weight (males), hyperplasia of spleen red pulp and femur bone marrow (both sexes) were observed. At 200 mg/kg, decreases in locomotor activity and salivation (both sexes), reduced food consumption (both sexes), decreases in RBC, HGB, HCT and increases in MCV, MCH, BUN, T-BIL (males), enlargement of spleen (both sexes), increased weight of spleen (males), hyperplasia of spleen red pulp and femur bone marrow and extramedullary hematopoiesis of liver (both sexes), atrophy of thymus and corpus luteum hyperplasia of ovary (females) were observed. At 600 mg/kg, decreases in locomotor activity, cyanosis (both sexes), reddish tear, and salivation (males), mortality (4 out of 12 females), decreased body weight (females), reduced food consumption (both sexes), decreases in RBC, HGB, HCT and MCHC and increases in WBC, MCV, MCH, reticulocyte, neutrophil, lymphocyte, monocyte, AST, ALT, BUN, T-BIL, ALB, Ca and A/G ratio (males), enlargement of spleen, increased weights of spleen (both sexes), liver (males), kidney and ovary, decreased weights of thymus (females), hyperplasia of spleen red pulp, hyperplasia of femur bone marrow and extramedullary hematopoiesis of liver (both sexes), and atrophy of thymus and corpus luteum hyperplasia of ovary (females) were observed. Regarding the reproduction and development toxicities, there were no treatment-related changes in precoital time, mating index, fertility index and pregnancy index at all doses tested. At 22 and 67 mg/kg, there were no adverse effects on all the parameters observed. At 200 mg/ kg, decreased body weight of pups (day 4 p.p.) were observed. At 600 mg/kg, decreased body weight of pups (day 0 and 4 p.p.) and viability index (day 4 p.p.), increased incidence of newborns dead or with abnormal clinical signs were observed. The results suggest that the NOAELs for general toxicity are < 22 mg/kg, LOAELs are 22 mg/kg and the NOAELs for reproductive toxicity are 67 mg/kg.

• Korean Journal of Agricultural Science
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• v.17 no.1
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• pp.26-33
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• 1990

This study was conducted to estimate heritabilities and genetic correlations of economic traits and body conformations in Korean Native Ogol fowl. The data analyzed were the record of 450 pullets bred from 150 dams and 20 sires of the fowl obtained from June 18, 1987 to February 6, 1989. The results of this study were summarized as follows ; The estimates of heritability for body weight, egg weight and shank length from combined variance components were relatively high, ranging from 0.415 to 0.558, while those for age at first egg, egg production and breast width were moderate, ranging from 0.301 to 0.334. For genetic correlations, body weights were negatively correlated with egg production, ranging from -0.552 to -0.309, while positive correlations were found between body weight and egg weight, ranging from 0.285 to 0.380. Also, egg production was negatively correlated with egg weight, ranging from -0.383 to -0.381. The shank length showed very high positive correlations with the body weights and age at 1st egg, ranging from 0.328 to 0.843. Hence the improvement in shank length will increase the body weight as well as the age at 1st egg.

• Journal of the Korean Chemical Society
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• v.62 no.4
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• pp.288-298
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• 2018

In this study, we surveyed pre- and post-perceptions of fourteen science teachers related to the atmosphere composition of molecules with different masses by the developed test. As a result of the test, the teachers were classified into two types of thoughts; One of them is considered the atmosphere to be a homogeneous solution, and the other is a thought that the composition ratio of the atmosphere was not homogeneous considering the different weights of particles. The two types were reclassified into three categories; one of them is considering large gravity effect, another is considering small gravity effect, and the other is considering medium scale gravity effect. Total six types of thoughts were found from the pre-test. After introducing crosscutting concepts which are related to the composition of atmosphere. The teachers discussed the phenomena with the molecular motion by weights of atoms and temperature, the homogeneity of the solution of air in chemistry domain. They also discussed with the relationship between mass and gravity and distance in physics domain. And the discussion included distribution of the atmosphere, convection phenomena, etc. After the discussion, the teachers changed their pre-conceptions to post-concoctions considering combined perspectives of gravity, mass, temperature, altitude etc. Through these changes, we are able to confirm the importance of crosscutting concepts covered in various disciplines. In the integrated science, we should help teachers to provide students with these types of thinking in order to form a coherent world-view and to carry out inquiry thinking as an intellectual tool.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.23 no.2
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• pp.157-172
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• 2024

Autonomous driving technology, when commercialized, has the potential to improve the safety, mobility, and environmental performance of transportation networks. However, safe autonomous driving may be hindered by poor sensor performance and limitations in long-distance detection. Therefore, cooperative autonomous driving that can supplement information collected from surrounding vehicles and infrastructure is essential. In addition, since HDVs, AVs, and CAVs have different ranges of perceivable information and different response protocols, countermeasures are needed for mixed traffic that occur during the transition period of autonomous driving technology. There is a lack of research on traffic flow optimization that considers the penetration rate of autonomous vehicles and the different characteristics of each road segment. The objective of this study is to develop weights based on safety, operational, and environmental factors for each infrastructure control use case and autonomous vehicle MPR. To develop an integrated evaluation index, infra-guidance AHP and hybrid AHP weights were combined. Based on the results of this study, it can be used to give right of way to each vehicle to optimize mixed traffic.

• Korean Journal of Food Science and Technology
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• v.29 no.1
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• pp.167-172
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• 1997

Effect of combined preparation (DWP715) containing Alaska pollack extract, maltol, ascorbic acid and nicotinamide on decreasing of blood alcohol was evaluated in human blood. Treatment of DWP715 prior to administration of 25% alcohol (100 mL) decreased alcohol concentration in blood and showed significant difference after 2 hours. The pharmacokinetic parameters such as area under the concentration-time curve (AUC), $C_{max},\;T_{max}\;and\;T_{1/2}$ were also decreased and delayed when compared with control values. Effects of DWP715 on anti-fatigue and anti-oxidation activities were also studied in the restraint stress model using various parameters (GOT, GPT, LDH values and organ weights) on mild condition and examined through the content of lipid peroxide induced by 2% $CCl_4$ in mouse livers. While GPT level, thymus and adrenal weight were not influenced by DWP715 dosing, LDH, GOT level and spleen weight used as a parameter against fatigue and stress states were recovered almost to the nomal level. Furthermore, lipid peroxidation due to $CCl_4$ was significantly inhibited by DWP715 treatment. These results suggest that DWP715 seems to metabolize the blood alcohol rapidly and to restore the damaged liver and fatigue conditions which was caused by alcohol metabolism to normal condition.

• Horticultural Science & Technology
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• v.34 no.6
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• pp.878-885
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• 2016

A study was conducted to examine the effects of light quality on the growth and phytochemical contents of ice plant in a closed-type plant production system. Seeds were sown in a 128-cell plug tray using rockwool. The seedlings were then transplanted into a deep floating technique system with recirculating nutrient solution (EC $1.5dS{\cdot}m^{-1}$, pH 6.5) in a closed-type plant production system. The nutrient solution was supplied at two weeks after transplanting with 2.0 mM NaCl concentration in all treatments for the development of the bladder cells. The three light sources with different light qualities used were as followed; FL (fluorescent lamps), combined RW LED (red:white = 7:3), and combined RBW LED (red:blue:white = 8:1:1) at $150{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ PPFD with a photoperiod of 14/10 hours (light/dark). The results showed that the FL treatment had the greatest growth enhancement effects on the leaf area and the fresh and dry weights of the shoots and roots. The SPAD values were significantly higher under the FL and RBW LED treatments, at 29.8 and 30.6, respectively. No significant difference was observed in salinity under all treatments. Chlorophyll fluorescence was significantly higher under the FL treatment. The total phenol content and antioxidant activity were the highest under the RBW LED treatment. The total flavonoid content was significantly higher under the RBW LED and FL treatments. Hence, the results indicate that the growth of ice plant was maximized under the FL treatment. The phytochemical contents were maximized under the RBW LED treatment.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.10
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• pp.1395-1399
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• 2004

The objective of this study was to evaluate the effect of dietary fat inclusion on nutrient intake, body weight, milk production, return to estrus, pregnancy and lambing of winter-lambing, postpartum Awassi ewes. Thirty multiparous, winter-lambing Awassi ewes (body weight=51${\pm}$7.0 kg) were randomly assigned to three dietary treatments (n=10) for 62 days using a completely randomized design. Experimental diets were isonitrogenous, and were formulated to contain 0 (CON), 2.5 (MF), and 5% (HF) added fat, and 33% of the dietary crude protein (CP) as undegradable intake protein (UIP). On day 26 postpartum (day 0=parturition), ewes and their lambs were housed in individual pens for 28 days. Feed offered and refused was recorded daily. At the end of this period, ewes and their lambs within each treatment were combined into one group and fed their respective diet ad libitum. One fertile Awassi ram fitted with a marking harness was allowed with each group for 34 days. No significant (p>0.05) differences in dry matter intake, organic matter intake, and crude protein intake were observed for ewes fed the three experimental diets. No difference was observed in metabolizable energy intake (MEI) for ewes fed the CON and the MF diets (average 8.3 Mcal/d) diet. However, ewes fed the HF diet had greater(p<0.05) MEI compared with the rest of the treatments. Ewe body weights increased throughout the study, unaffected by the experimental diets. No significant differences in milk production were found among ewes fed the three experimental diets. No significant differences were observed in pregnancy rate (6/10, 5/10, 6/10 for CON, MF and HF diets, respectively), lambing rate and the number of lambs per ewe among the three treatments. postpartum reproductive performance of well-fed, winter-lambing Awassi ewes.