• Title/Summary/Keyword: Cold test

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Developing a Model for Estimating Leaf Temperature of Cnidium officinale Makino Based on Black Globe Temperature (흑구온도를 이용한 천궁 엽온 예측 모델 개발)

  • Seo, Young Jin;Nam, Hyo Hoon;Jang, Won Cheol;Lee, Bu Yong
    • Korean Journal of Medicinal Crop Science
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    • v.26 no.6
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    • pp.447-454
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    • 2018
  • Background: The leaf temperature ($T_{LEAF}$) is one of the most important physical parameters governing water and carbon flux, including evapotranspiration, photosynthesis and respiration. Cnidium officinale is one of the important folk medicines for counteracting a variety of diseases, and is particularly used as a traditional medicinal crop in the treatment of female genital inflammatory diseases. In this study, we developed a model to estimate $T_{Leaf}$ of Cnidium officinale Makino based on black globe temperature ($T_{BGT}$). Methods and Results: This study was performed from April to July 2018 in field characterized by a valley and alluvial fan topography. Databases of $T_{LEAF}$ were curated by infrared thermometry, along with meteorological instruments, including a thermometer, a pyranometer, and an anemometer. Linear regression analysis and Student's t-test were performed to evaluate the performance of the model and significance of the parameters. The correlation coefficient between observed $T_{LEAF}$ and calculated $T_{BGT}$ obtained using an equation, developed to predict $T_{LEAF}$ based on $T_{BGT}$ was very high ($r^2=0.9500$, p < 0.0001). There was a positive relationship between $T_{BGT}$ and solar radiation ($r^2=0.8556$, p < 0.0001), but a negative relationship between $T_{BGT}$ and wind speed ($r^2=0.9707$, p < 0.0001). These results imply that heat exchange in leaves seems to be mainly controlled by solar radiation and wind speed. The correlation coefficient between actual and estimated $T_{BGT}$ was 0.9710 (p < 0.0001). Conclusions: The developed model can be used to accurately estimate the $T_{Leaf}$ of Cnidium officinale Makino and has the potential to become a practical alternative to assessing cold and heat stress.

A study on weight reduction of bracket using CAE program (CAE 프로그램을 이용한 브래킷 경량화에 관한 연구)

  • Kang, Hyung-Suk;Han, Bong-Suk;Han, Yu-Jin;Choi, Doo-Sun;Kim, Tae-Min;Shin, Bong-Cheol;Song, Ki-Hyeok
    • Design & Manufacturing
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    • v.12 no.3
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    • pp.25-30
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    • 2018
  • Recently The automotive industry is trying to increase the energy efficiency by reducing the weight of the car body and engine components as a way to achieve high energy efficiency. In particular, the reduction of the weight of the vehicle through the weight reduction of the vehicle body has the advantage that the fuel consumption and the output can be improved. But at the same time, there is the disadvantage that the strength becomes weak due to the reduction of the material thickness. Therefore, in order to overcome these disadvantages, materials with high strength according to the unit thickness have been actively developed, and researches for applying them have also been increasing. In this study, we will investigate the application of cold rolled steel sheet, which is a lightweight material, to a horn bracket that secures a installed in an automobile engine room. The horn bracket secures the horn on the car engine and is bolted to the outer wall of the engine. The momentum is acted on the bracket due to the distance between the bolt fastening part and the car horn installed on the bracket end side. Therefore, the body part of the bracket is more likely to be destroyed by the influence of the continuous stress. In this paper, design optimization for weight reduction and strength enhancement was performed to solve this problem, and possibility of applying the rolled steel sheet material as lightweight material by tensile test and fabrication was confirmed.

Effect of Pre-Heat Treatment on Bonding Properties in Ti/Al/STS Clad Materials (Ti/Al/STS 클래드재의 접합특성에 미치는 예비 열처리의 영향)

  • Bae, Dong-Hyun;Jung, Su-Jung;Cho, Young-Rae;Jung, Won-Sup;Jung, Ho-Shin;Kang, Chang-Yong;Bae, Dong-Su
    • Korean Journal of Metals and Materials
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    • v.47 no.9
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    • pp.573-579
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    • 2009
  • Titanium/aluminum/stainless steel(Ti/Al/STS) clad materials have received much attention due to their high specific strength and corrosion-resisting properties. However, it is difficult to fabricate these materials, because titanium oxide is easily formed on the titanium surface during heat treatment. The aim of the present study is to derive optimized cladding conditions and thereupon obtain the stable quality of Ti/Al/STS clad materials. Ti sheets were prepared with and without pre-heat treatment and Ti/Al/STS clad materials were then fabricated by cold rolling and a post-heat treatment process. Microstructure of the Ti/Al and STS/Al interfaces was observed using a Scanning Electron Microscope(SEM) and an Energy Dispersed X-ray Analyser(EDX) in order to investigate the effects of Ti pre-heat treatment on the bond properties of Ti/Al/STS clad materials. Diffusion bonding was observed at both the Ti/Al and STS/Al interfaces. The bonding force of the clad material with non-heat treated Ti was higher than that with pre-heat treated Ti before the cladding process. The bonding force decreased rapidly beyond $400^{\circ}C$, because the formed Ti oxide inhibited the joining process between Ti and Al. Bonding forces of STS/Al were lower than those of Ti/Al, because brittle $Fe_3Al$, $Al_3Fe$ intermetallic compounds were formed at the interface of STS/Al during the cladding process. In addition, delamination of the clad material with pre-heat treated Ti was observed at the Ti/Al interface after a cupping test.

The Effect of Various Processing Conditions on Temperature Distribution in Steam-air Retort (스팀-에어 레토르트의 온도분포에 미치는 공정 변수 영향)

  • Lee, Sun-Young;Shin, Hae-Hun;In, Ye-Won;Cho, Hyung-Yong
    • Food Engineering Progress
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    • v.23 no.2
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    • pp.87-93
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    • 2019
  • Temperature distribution studies were performed in steam-air retort to investigate the influence of various processing conditions (come-up time, sterilization temperature, and internal pressure throughout the steam-air retort). Retort temperature data were analyzed for temperature deviations during holding phase, maximum temperature difference between test locations at the beginning and after 1, 3, and 5 min of the holding phase, and box-and-whiskers plots for each location during the holding phase. The results showed that high sterilization temperature led to a more uniform temperature distribution than low sterilization temperature (pasteurization). In pasteurization condition, the temperature stability was slightly increased by increasing pressure during the holding phase. On the other hand, the temperature stability was slightly decreased in high sterilization temperature condition. Programming of the come-up phase did not affect the temperature uniformity. In addition, the slowest cold spot was found at the bottom floor during the holding phase in all conditions. This study determined that the temperature distribution is affected by retort processing conditions, but the steam-air retort needs more validation tests for temperature stability.

Effect of pumice powder and artificial lightweight fine aggregate on self-compacting mortar

  • Etli, Serkan;Cemalgil, Selim;Onat, Onur
    • Computers and Concrete
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    • v.27 no.3
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    • pp.241-252
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    • 2021
  • An experimental program was conducted to investigate the fresh properties, mechanical properties and durability characteristics of the self-compacting mortars (SCM) produced with pumice powder and Artificial Lightweight Fine Aggregate (aLWFA). aLWFA was produced by using fly ash. A total of 16 different mixtures were designed with a constant water-binder ratio of 0.37, in which natural sands were partially replaced with aLWFA and pumice powder at different volume fractions of 5%, 10% and 15%. The artificial lightweight aggregates used in this study were manufactured through cold bonding pelletisation of 90% of class-F fly ash and 10% of Portland cement in a tilted pan with an ambient temperature and moisture content. Flowability tests were conducted on the fresh mortar mixtures beforehand, to determine the self-compacting characteristics on the basis of EFNARC. To determine the conformity of the fresh mortar characteristics with the standards, mini-slump and mini-V-funnel tests were carried out. Hardened state tests were conducted after 7, 28 and 56 days to determine the flexural strength and axial compressive strength respectively. Durability, sorptivity, permeability and density tests were conducted at the end of 28 days of curing time. The test results showed that the pumice powder replacement improved both the fresh state and the hardened state characteristics of the mortar and the optimum mixture ratio was determined as 15%, considering other studies in the literature. In the aLWFA mixtures used, the mechanical and durability characteristics of the modified compositions were very close to the control mixture. It is concluded in this study that mixtures with pumice powder replacement eliminated the negative effects of the aLWFA in the mortars and made a positive contribution.

Study on Breakup Characteristics of Gel Propellant Using Pressure Swirl Injector (압력선회형 인젝터를 이용한 젤 추진제의 분열특성 연구)

  • Cho, Janghee;Lee, Donghee;Kim, Sulhee;Lee, Donggeun;Moon, Heejang
    • Journal of the Korean Society of Propulsion Engineers
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    • v.25 no.5
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    • pp.10-17
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    • 2021
  • In this study, cold-flow test of simulant gel is conducted using a pressure swirl injector to identify spray characteristics according to gellant weight percent. Experiment results show the aircore is developed locally at the nozzle and expanded to the entire swirl chamber as the supply pressure increases. The aircore formation of simulant gel showed no significant difference compared to Newtonian fluid. The spray pattern was classified into four distinct shapes where relationship between the breakup regimes and dimensionless numbers were investigated. In the future, additional study is necessary to understand the aircore formation mechanism, stability and spray characteristics at different configuration of the swirl chamber shape.

Artemisia annua L. Extracts Improved Insulin Resistance via Changing Adiponectin, Leptin and Resistin Production in HFD/STZ Diabetic Mice

  • Ghanbari, Mahshid;Lamuki, Mohammad Shokrzadeh;Habibi, Emran;Sadeghimahalli, Forouzan
    • Journal of Pharmacopuncture
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    • v.25 no.2
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    • pp.130-137
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    • 2022
  • Objectives: Insulin resistance (IR) is major cause of type 2 diabetes (T2D), and adipokines (e.g., adiponectin, leptin, and resistin) play an important role in insulin sensitivity. Medicinal plants are frequently used for T2D treatment. This study investigates the effect of Artemisia annua L. (AA) extracts on adipokines in mice with high-fat-diet (HFD)/streptozotocin (STZ)-induced T2D. Methods: We divided 60 mice into 12 groups (n = 5 per group): control, untreated T2D, treated T2D, and 9 other groups. T2D was induced in all groups, except controls, by 8 weeks of HFD and STZ injection. The treated T2D group was administered 250 mg/kg of metformin (MTF), while the nine other groups were treated with 100, 200, and 400 mg/kg of hot-water extract (HWE), cold-water extract (CWE), and alcoholic extract (ALE) of AA (daily oral gavage) along with 250 mg/kg of MTF for 4 weeks. The intraperitoneal glucose tolerance test (IPGTT) was performed, and the homeostasis model assessment of adiponectin (HOMA-AD) index and blood glucose and serum insulin, leptin, adiponectin, and resistin levels were measured. Results: Similar to MTF, all three types of AA extracts (HWEs, CWEs, and ALEs) significantly (p < 0.0001) decreased the area under the curve (AUC) of glucose during the IPGTT, the HOMA-AD index, blood glucose levels, and serum insulin, leptin, and resistin levels and increased serum adiponectin levels in the MTF group compared to the T2D group (p < 0.0001). The HWEs affected adipokine release, while the CWEs and ALEs decreased leptin and resistin production. Conclusion: Water and alcoholic AA extracts have an antihyperglycemic and antihyperinsulinemic effect on HFD/STZ diabetic mice. In addition, they decrease IR by reducing leptin and resistin production and increasing adiponectin secretion from adipocytes.

A Study on the Utilization of Urban Garden Design Derived from the Traditional Farming Method Gyeonjongbeop from the Joseon Period: Focused on Imwongyeongjeji Bolliji

  • Hong, In-Kyoung;Yun, Hyung-Kwon;Chae, Young;Lee, Sang-Mi;Jung, Young-Bin;Lee, Mi-Ra
    • Journal of People, Plants, and Environment
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    • v.23 no.4
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    • pp.423-432
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    • 2020
  • Background and objective: Traditional farming is winning recognition as a sustainable alternative farming method. As urban farming increases in South Korea, it is crucial to develop more sustainable farming techniques. Gyeonjongbeop is the traditional farming method introduced in the Joseon period. This study was conducted to propose a productive garden model suitable for urban farming through the interpretation of traditional farming methods contained in Imwongyeongjeji Bolliji and to test the model on an actual field. Methods: Using the design and cropping system of Gyeonjongbeop as the research materials, we reviewed its tillage and cultivation and examined the applicability. We proposed a modified method by extracting parts applicable to urban farming. According to the methods, we created a garden with ridges and furrows, cultivated proper vegetables, and evaluated their growth. Results: Raphanus sativus, Allium fistulosum L., Brassica juncea, and Spinacia oleracea grown on ridges showed higher growth than those grown on a conventional flat field. The growth of Hordeum vulgare var. hexastichon and Triticum aestivum L. on furrows was also slightly higher. This proved that the method could make up for the deficiencies of barley and wheat that are weak against winds and cold and are easily destroyed by the spring rains. Conclusion: Ridge and furrow cultivation derived from Gyeonjongbeop can be an efficient urban farming system compared to the conventional cultivation in flat fields. The system can use fallow lands in winter for year-round urban farming. In addition, the application of the traditional farming system can enhance the humanistic value of urban farming.

A clinical study on a patient with hypothyroidism (생간건비탕가미방(生肝健脾湯加味方)을 이용한 갑상선기능저하증 치험1예(例))

  • Koo, Jin Suk;Kim, Bong Hyun;Seo, Bu Il
    • The Korea Journal of Herbology
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    • v.29 no.5
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    • pp.17-21
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    • 2014
  • Objectives : Hypothyroidism is a common endocrine disorder in which the thyroid gland does not produce enough thyroid hormone. It can cause a number of symptoms, such as tiredness, poor ability to tolerate cold, and weight gain. The purpose of this study was to report the clinical effects of herbal medicine on hypothyroidism. Methods : We employed oriental medical treatments; herbal-medication (Saenggangeonbi - tang gamibang), acupuncture and moxibustion. At the same time, the patient started to exercise. We treated the patient two or three times a week with oriental therapy method. She took medicine three times a day after a meal. During taking medicine, we let the patient avoid fatty food, flour based food, and alcohol. The symptoms and normalization of the thyroxine and TSH levels are important points of evaluating the patient's condition. So the patient measured the body weight and took a blood test a time per two months and compared the results with previous results. Results : After taking treatment - acupuncture and moxibustion during 6 months - and taking herbal-medicine, the level of TSH, fT4, T4 and T3 became normalized. The body weight was decreased about 18 pounds. In advance, the symptom of tiredness, edema was much improved. Conclusion : Herbal medicine (Saenggangeonbi-tang gamibang) was effective in the treatment of hypothyroidism and it helped to normalize the level of TSH, fT4, T4 AND T3.

Effects of herbal Cp soap on acne skin (한약 저온숙성비누가 여드름 피부에 미치는 영향)

  • Choi, Sang Rak;Seo, Bu Il;Koo, Jin Suk
    • The Korea Journal of Herbology
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    • v.34 no.3
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    • pp.37-44
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    • 2019
  • Objectives : Acne is a common disease that affects more than 70% of adolescents. Acne patients have a poor quality of life compared to patients with other skin diseases. We tried to demonstrate the effectiveness of acne treatment using cleansing soap which is easily used in daily life. Methods : We selected 20 students with acne symptoms on their facial skin. We made herbal Cp (Cold process) soaps using Seosiokyongsan, Kyungohkgo, Hwangryunhaedoktang and Baeksoooh and distributed them to experiment participants. We let them wash their face in the morning and evening for 6 weeks using herbal Cp soap. Prior to the experiment, their skin condition was checked and assessed using A-ONE Smart One-Click Automatic Facial Diagnosis System three times at 3-week intervals. Acne status was classified into 6 stages according to KAGS and acne status was also measured 3 times in total. After the experiment, the changes of skin were analyzed through facial analysis test. Results : Based on the KAGS classification, the condition of acne has improved as a whole. The state of moisture was gradually increased and the state of skin oil was significantly decreased after 6 weeks of using soap compared to before using soap. Conclusions : Cp soaps made from four kinds of herbal medicine are believed to improve the condition of acne by increasing the moisture of the facial skin and decreasing the skin oil content.