• Title/Summary/Keyword: CHANGE OF TEMPERATURE

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Evaluation of the Shear Strength and Stiffness of Frozen Soil with a Low Water Content (함수비가 낮은 동결토의 전단강도 및 강성 평가)

  • Kim, Sang Yeob;Lee, Jong-Sub;Kim, Young Seok;Byun, Yong-Hoon
    • The Journal of Engineering Geology
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    • v.25 no.1
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    • pp.93-102
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    • 2015
  • The characteristics of frozen soils are one of most important factors for foundation design in cold region. The objective of this study is to evaluate the shear strength and stiffness of frozen soils according to the confining conditions during the freezing and shearing phase. A direct shear box is constructed for the frozen specimens and bender elements are mounted on the wall of the shear box to measure shear wave velocities. Specimens are prepared by mixing sand and silt with a silt fraction of 30% in weight and the degree of saturation of 10%, giving a relative density of 60% for all tests. The temperature of the specimens in the freezer is allowed to fall below -5℃, and then direct shear tests are performed. A series of vertical stresses are applied during the freezing and shearing phase. Shear stress, vertical displacement, and shear wave along the horizontal displacement are measured. Experimental results show that in all the tests, shear strength increases with increasing vertical stress applied during the freezing and shearing phases. The magnitude of the increase in shear strength with increasing vertical stress during shearing under fixed vertical stress in the frozen state is smaller than the magnitude of the increase in vertical stress during freezing and shearing. In addition, the change in shear wave velocities varies with the position of the bender elements. In the case of shear waves passing through the shear plane, the shear wave velocities decrease with increasing horizontal displacement. This study provides an evaluation of the properties of shear strength and stiffness of frozen soils under varied confining condition.

The Expression of Oncogenes on the Radiation-induced Apoptosis in SCK Mammary Adenocarcinoma Cell Line (SCK 선암세포주에서 방사선 조사에 의해 유도되는 Apoptosis에 미치는 암유전자의 발현)

  • Lee Hyung Sik;Park Hong Kyu;Moon Chang Woo;Yoon Seon Min;Hur Won Joo;Jeong Su Jin;Jeong Min Ho;Lee Sang Hwa
    • Radiation Oncology Journal
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    • v.17 no.1
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    • pp.70-77
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    • 1999
  • Purpose : The expression of p53, P211WAF/CIP, Bcl-2, and Bax underlying the radiation-induced apoptosis in different pH environments using SCK mammary adenocarcinoma cell line was investigated. Materials and Methods Mammary adenocarcinoma cells of hi) mice (SCK cells) in exponential growth phase were irradiated with a linear accelerator at room temperature. The cells were irradiated with 12 Gy and one hour later, the media was replaced with fresh media at a different pHs. After Incubation at 37Microbioiogy, College of Medicine Dong A University for 0$\~$48 h, the extort of apoptosis was determined using agarose gel electrophoresis and flow cytometry. The progression of cells through the cell cycle after irradiation in different pHs was also determined with flow cytometry. Western blot analysis was used to monitor p53, p211WAFfCIP, Bcl-2, and Bu protein levels. Results : The induction of apoptosis by irradiation in pH 6.6 medium was markedly less than that in pH 7.5 medium. The radiation-induced G2IM arrest in pH 6.6 medium lasted markedly longer than that in pH 7.5 medium. Considerable amounts of p53 and p21 proteins already existed at pH 7.5 and increased the level of p53 and p21 significantly after 12 Gy X-irradiation. An incubation at pH 6.6 after 12 Gy X-irradiation did not change the level of p53 and p21 protein levels significantly. Bcl-2 proteins were not significantly affected by radiation and showed no correlation with cell susceptibility to radiation-induced apoptosis in different pHs. An exposure to 12 Gy of X-rays increased the level of Bax protein at pH 7.5 but at pH 6.6, it was slight. Conclusions : The molecular mechanism underlying radiation-induced apoptosis in dinerent pH environments using SCK mammary adenocarcinoma cell line was dependent of the expression p53 and P211YVAF/CIP proteins. We may propose following hypothesis that an acidic stress augments the radiation-induced G2iM arrest, which inhibiting the irradiated cells undergo post-mitotic apoptosis. The effects of environmental acidity on anti-apoptotic and pro-apoptotic function of Bcl-2 family was unclear in SCK mammary adenocarcinoma cell line.

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Effect of Packaging Methods on the Quality Properties of Stick Type Restructured Jerky (재구성 스틱형 육포의 포장방법이 저장중 품질특성에 미치는 영향)

  • Choi, Yun-Sang;Jeong, Jong-Youn;Choi, Ji-Hun;Han, Doo-Jeong;Kim, Hack-Youn;Lee, Mi-Ai;Paik, Hyun-Dong;Kim, Cheon-Jei
    • Food Science of Animal Resources
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    • v.27 no.3
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    • pp.290-298
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    • 2007
  • The effect of packaging methods on the quality of stick type restructured jerky was investigated in terms of pH, water activity $(A_w)$, TBA (thiobarbituric acid) value, total bacterial counts, and sensory evaluation during storage at room temperature $(25^{\circ}C)$ for 90 days. The jerky was subjected to plastic or vacuum packaging at $(25^{\circ}C)$. The pH decreased slightly as storage time increased (p<0.05), but there were no significant differences between the packaging methods. The water activity of jerky in plastic packaging decreased as storage time increased (p<0.05), however jerky in vacuum packaging showed no significant change. Vacuum packaging resulted in a higher water activity value than plastic packaging. The TBA and hardness values decreased as storage time increased (p<0.05), and there were significant differences between packaging methods during the storage period (p<0.05). The total bacterial counts in vacuum packaged jerky were lower than jerky in plastic packaging. The sensory evaluation of each treatment decreased slightly as storage time increased (p<0.05), however there was no significant difference between packaging methods. Based on our findings, we conclude that vacuum packaging provides more effective storage than common packaging of jerky.

Effect of Hot-water Dipping on Inhibiting Red Discoloration of Basal Part in Chicon (열수 침지 처리가 치콘 절단면의 적변 억제에 미치는 영향)

  • Jung, Hyun Jin;Kang, Ho-Min
    • Horticultural Science & Technology
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    • v.32 no.3
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    • pp.353-358
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    • 2014
  • Hot water dipping test was conducted for chicon to restrict red discoloration of its basal part which impairs the product value during sales. Hot water dipping treatment was given to chicon for 4 min and for 8 min at $38^{\circ}C$ and for 2 min and 4 min at $42^{\circ}C$, and for 1 min and 2 min at $45^{\circ}C$, along with control (for one min at $20^{\circ}C$). The red discoloration indices of basal part of chicon during sensory evaluation on the sixth day of storage under the storage temperature at $10^{\circ}C$ was lower at $42^{\circ}C$ for 2 min, $42^{\circ}C$ for 4 min and $45^{\circ}C$ for 1 min treatments. The color change value of the basal part in chicon measured by colorimeter showed that the lowest ${\Delta}a^*$ and ${\Delta}h$ were maintained in the basal part of chicon treated at $42^{\circ}C$ for 2 min. Whereas, color changes in $42^{\circ}C$ for 2 min and $45^{\circ}C$ for 1 min treatments were significantly low as compared with that of control. The contents of total phenolic compounds which are the substances that cause red discoloration of basal part in chicon were lowest at $42^{\circ}C$ for 2 min, $42^{\circ}C$ for 4 min and $45^{\circ}C$ for 1 min treatments. The activity of phenylalanine ammonia lyase (PAL) resposible for in the synthesis of phenolic substances was the least in $42^{\circ}C$ for 2 min treatment. Whereas, PAL activity of the chicons treated a t $42^{\circ}C$ for 2 min and at $45^{\circ}C$ for 1 min were significantly lower than that of control. However, red discoloration was progressed as similar level with that of control in the basal part of chicon at $45^{\circ}C$ for 2 min. The contents of total phenolic compounds and PAL activity in this treatment were not significantly different from those in control. The polyphenol oxidase (PPO) activity which causes red discoloration of cut tissues was low in all the treatments including $42^{\circ}C$ and $45^{\circ}C$ treatment at which no inhibition effects of the red discoloration of basal part of chicon were observed. When the correlation coefficient between each investigated index was tested, most of them showed high correlation except the PPO activity and particularly and the red discoloration index and sensory evaluation ${\Delta}h$ values, and PAL activity and total phenolic compounds content were $r=0.927^{**}$, and $r=0.942^{**}$, respectively.

Effects of Cellulose and Pectin on Diet-induced Thermogenesis in Young Women (한국인 젊은 여성에서 셀룰로오스 및 펙틴이 식이성 발열효과에 미치는 영향)

  • Oh, Seung-Ho;Park, Jeong-Jin;Choi, In-Seon;Ro, Hee-Kyong
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.36 no.2
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    • pp.194-200
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    • 2007
  • The purpose of this study was to observe the effects of fiber free control diet (CD), cellulose diet (CED) and pectin diet (PTD) on diet induced thermogenesis (DIT) in healthy Korean woman for 3 hours. The three test diets were as follows: CD (carbohydrate intake: 63.4% of energy, protein intake: 14.0% of energy and fat intake: 25.8% of energy), CED (carbohydrate intake: 62.5% of energy, protein intake: 14.0% of energy and fat intake: 26.1% of energy) and PTD (carbohydrate intake: 62.7% of energy, protein intake: 14.0% of energy and fat intake: 26.2 of energy). Groups were served 10 g of cellulose for CED and 10 g of pectin for PTD, respectively. DIT was measured at fasting state and at 30, 60, 90, 120, 150 and 180 min after consuming each diet. The mean age of all subjects was $22.3{\pm}1.9$ years. Body weight was $52.5{\pm}8.6$ kg and body mass index was $20.6{\pm}2.7kg/m^2$. Preprandial resting energy expenditure was $0.79{\pm}0.02kcal/min$ and postprandial DIT were $14.05{\pm}0.62%$ for CD, $9.33{\pm}0.62%$ for CED, $11.07{\pm}1.35%$ for PTD as a percentage of the energy load. DIT of CD was significantly higher than those of CED and PTD. There was no significant difference in postprandial change in body temperature after consuming each test diets and the sympathetic nervous system activity measured by heart rate was significantly higher in CD than CED and PTD (p<0.05). With this study, it can be concluded that CED and PTD have significantly lowered in DIT (p<0.05). We didn't show the correlation of the factors that relate in DIT; thus, further experiments on that matter should be followed.

Eco-friendly and efficient in situ restoration of the constructed sea stream by bioaugmentation of a microbial consortium (복합미생물 생물증강법을 이용한 인공해수하천의 친환경 효율적 현장 수질정화)

  • Yoo, Jangyeon;Kim, In-Soo;Kim, Soo-Hyeon;Ekpeghere, Kalu I.;Chang, Jae-Soo;Park, Young-In;Koh, Sung-Cheol
    • Korean Journal of Microbiology
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    • v.53 no.2
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    • pp.83-96
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    • 2017
  • A constructed sea stream in Yeongdo, Busan, Republic of Korea is mostly static due to the lifted stream bed and tidal characters, and receives domestic wastewater nearby, causing a consistent odor production and water quality degradation. Bioaugmentation of a microbial consortium was proposed as an effective and economical restoration technology to restore the polluted stream. The microbial consortium activated on site was augmented on a periodic basis (7~10 days) into the most polluted site (Site 2) which was chosen considering the pollution level and tidal movement. Physicochemical parameters of water qualities were monitored including pH, temperature, DO, ORP, SS, COD, T-N, and T-P. COD and microbial community analyses of the sediments were also performed. A significant reduction in SS, COD, T-N, and COD (sediment) at Site 2 occurred showing their removal rates 51%, 58% and 27% and 35%, respectively, in 13 months while T-P increased by 47%. In most of the test sites, population densities of sulfate reducing bacterial (SRB) groups (Desulfobacteraceae_uc_s, Desulfobacterales_uc_s, Desulfuromonadaceae_uc_s, Desulfuromonas_g1_uc, and Desulfobacter postgatei) and Anaerolinaeles was observed to generally decrease after the bioaugmentation while those of Gamma-proteobacteria (NOR5-6B_s and NOR5-6A_s), Bacteroidales_uc_s, and Flavobacteriales_uc_s appeared to generally increase. Aerobic microbial communities (Flavobacteriaceae_uc_s) were dominant in St. 4 that showed the highest level of DO and least level of COD. These microbial communities could be used as an indicator organism to monitor the restoration process. The alpha diversity indices (OTUs, Chao1, and Shannon) of microbial communities generally decreased after the augmentation. Fast uniFrac analysis of all the samples of different sites and dates showed that there was a similarity in the microbial community structures regardless of samples as the augmentation advanced in comparison with before- and early bioaugmentation event, indicating occurrence of changing of the indigenous microbial community structures. It was concluded that the bioaugmentation could improve the polluted water quality and simultaneously change the microbial community structures via their niche changes. This in situ remediation technology will contribute to an eco-friendly and economically cleaning up of polluted streams of brine water and freshwater.

Study on the Current Status of Smart Garden (스마트가든의 인식경향에 관한 연구)

  • Woo, Kyung-Sook;Suh, Joo-Hwan
    • Journal of the Korean Institute of Landscape Architecture
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    • v.49 no.2
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    • pp.51-60
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    • 2021
  • Modern society is becoming more informed and intelligent with the development of digital technology, in which humans, objects, and networks relate with each other. In accordance with the changing times, a garden system has emerged that makes it easy to supply the ideal temperature, humidity, sunlight, and moisture conditions to grow plants. Therefore, this study attempted to grasp the concept, perception, and trends of smart gardens, a recent concept. To achieve the purpose of this study, previous studies and text mining were used, and the results are as follows. First, the core characteristics of smart gardens are new gardens in which IoT technology and gardening techniques are fused in indoor and outdoor spaces due to technological developments and changes in people's lifestyles. As technology advances and the importance of the environment increases, smart gardens are becoming a reality due to the need for living spaces where humans and nature can co-exist. With the advent of smart gardens, it will be possible to contribute to gardens' vitalization to deal with changes in garden-related industries and people's lifestyles. Second, in current research related to smart gardens and users' experiences, the technical aspects of smart gardens are the most interesting. People value smart garden functions and technical aspects that enable a safe, comfortable, and convenient life, and subjective uses are emerging depending on individual tastes and the comfort with digital devices. Third, looking at the usage behavior of smart gardens, they are mainly used in indoor spaces, with edible plants are being grown. Due to the growing importance of the environment and concerns about climate change and a possible food crisis, the tendency is to prefer the cultivation of plants related to food, but the expansion of garden functions can satisfying users' needs with various technologies that allow for the growing of flowers. In addition, as users feel the shapes of smart gardens are new and sophisticated, it can be seen that design is an essential factor that helps to satisfy users. Currently, smart gardens are developing in terms of technology. However, the main components of the smart garden are the combination of humans, nature, and technology rather than focusing on growing plants conveniently by simply connecting potted plants and smart devices. It strengthens connectivity with various city services and smart homes. Smart gardens interact with the landscape of the architect's ideas rather than reproducing nature through science and technology. Therefore, it is necessary to have a design that considers the functions of the garden and the needs of users. In addition, by providing citizens indoor and urban parks and public facilities, it is possible to share the functions of communication and gardening among generations targeting those who do not enjoy 'smart' services due to age and bridge the digital device and information gap. Smart gardens have potential as a new landscaping space.

The Effects of Marine Sediments and NaCl as Impurities on the Calcination of Oyster Shells (굴패각 소성시 해저 퇴적물과 NaCl 불순물이 소성 특성에 미치는 영향)

  • Ha, Su Hyeon;Kim, Kangjoo;Kim, Seok-Hwi;Kim, Yeongkyoo
    • Economic and Environmental Geology
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    • v.52 no.3
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    • pp.223-230
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    • 2019
  • The calcination of oyster shells have been studied as the possible substitute for the limestone used as an absorbent of $SO_2$ gas. However, since pure shells can not be used in calcination process, some impurities are contained and the changes in the characteristics of the calcination products are expected. In this study, the surface characteristics of the calcination products are investigated by mineralogical analysis according to the contents of NaCl, which can be derived from sea water, and sediments on the surface of the shell as impurities. The marine sediments on the shells were mainly composed of quartz, albite, calcite, small amounts of amphibole and clay minerals such as ilite, chlorite and smectite. After calcination of oyster shells mixed with 0.2-4.0 wt% sediments at $900^{\circ}C$ for 2 hours, regardless of the dehydration, dehydroxylation, and phase change of these minerals at the lower temperature than this experiment, no noticeable changes were observed on the specific surface area of the calcined product. However, when mixed with 0.1 to 2.0 wt% NaCl, the specific surface area generally increases as compared with the shell sample before calcination. The specific surface area increases with increasing amount of salt, and then decreases again. This is closely related to the changes of surface morphology. As the amount of NaCl increases, the morphology of the surface is similar to that of gel. It changes into a slightly angular, smaller particle and again looks like gel with increasing amount of NaCl. Our results show that NaCl affects morphological changes probably caused by melting of some oyster shells, but may have different effects on the specific surface area of calcination product depending on the NaCl contents.

Estimation of the Second Flight Season of Chilo suppressalis (Lepidoptera: Crambidae) Adults in the Northeastern Chinese Areas (중국 동북부 지역에서 이화명나방(Chilo suppressalis)(Crambidae) 2화기 성충 발생 시기 추정)

  • Jung, Jin Kyo;Kim, Eun Young;Yang, Woonho;Lee, Seuk-Ki;Shin, Myeong Na;Yang, Jung-Wook;Ju, Hongguang;Jin, Dongcun;Pao, Jin;Wang, Jichun;Zhu, Feng
    • Korean journal of applied entomology
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    • v.61 no.2
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    • pp.335-347
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    • 2022
  • We investigated the emergence patterns of Chilo suppressalis (Lepidoptera: Crambidae) adults using sex pheromone traps in the three northeastern areas, Dandong (40°07'N 124°23'E) (Liaoning province), and Gongzhuling (43°30'N 124°49') and Longjing (42°46'N 129°26'E) (Jilin province), China, in 2020 and 2021. Two times of adult flight seasons were isolated clearly during the rice growing periods in the all areas, in which the first season from mid May to late July, and the second season from mid July to mid September were observed. The adult emergence seasons in the areas at higher latitude were later than that at lower latitude. Using the adult emergence data during the first flight seasons, the second flight seasons were estimated through insect phenology modelling, and compared with the observed data. Temperature-dependent life history models (developmental rate, development completion, survival rate, adult aging rate, total fecundity, oviposition completion, and adult survival completion) were collected or constructed for each life stage of C. suppressalis, in which the data from the four previous studies were used. Those models were combined in an insect phenology estimation software, PopModel, and operated for the observed areas. In the results, the phenology modelling operated with the models based on the data of shorter larval periods in the previous studies estimated more accurately the second flight seasons. In 2021, we investigated the change of damaged hill ratios of rice with observing the adult emergence at Dandong and Longjing, 2021. The increase periods of damaged hill ratios of rice were observed two times during the total rice cultivation season, which may be caused by different generations of C. suppressalis larvae.

Effects of Salts and Acid Solutions on the Weathering of Granite (화강암의 풍화에 미치는 염분과 산성용액의 영향)

  • Shon, Byung-Hyun;Jung, Jong-Hyeon;Kim, Hyun-Gyu;Yoo, Jeong-Gun;Lee, Hyung-Kun
    • Journal of Korean Society of Environmental Engineers
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    • v.27 no.1
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    • pp.101-108
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    • 2005
  • Because the stone cultural properties located outdoors, they have been altered and deteriorated in external appearance due to environmental factors such as acid rain, extreme change in temperature, and salts. Damage to stone cultural properties is accelerated particularly due to recent industrial development and environmental pollution. An experimental study was conducted to evaluate the effect of environmental contaminants on the weathering of granite. And as part of the developing of conservation method, $TiO_2$ catalyst was prepared and tested. When fresh granite was dipped into the salt and acid solutions, dissolution rate of eight minerals (Si, Mg, Ca, Na, K, Fe, Mn, Al) are abruptly increased at initial stage of reaction and then increased steadily until 100 cycles. After salt and acid solution experiments, the mineral compositions of the granite surface were lower then that of the fresh granite and density of the weathered granite was steadily decreased from $2.60\;g/cm^3$ to $2.56\;g/cm^3$, but Poissions ratio and absorption ratio were slightly increased. It was expected at stone cultural assets could be weathered by salts and acid rain. In the case of $TiO_2$ was coated to the granite, the dissolution rate of minerals and absorption ratio of $TiO_2$ coated granite were decreased. Therefore, the $TiO_2$ coating method tested in this study considered to be a viable method to assist in the conservation of stone cultural properties from environmental contaminants.