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Fundamental Study for Extension of Application of Recycled Concrete Aggregate: Spun High Strength Concrete (순환골재의 사용성 확대를 위한 연구: 원심력콘크리트로의 적용)

  • Sim, Jong-Sung;Park, Cheol-Woo;Park, Sung-Jae;Kim, Hyun-Jung;Kim, Taeg-Wang;Lee, Man-Suk
    • Journal of the Korean Recycled Construction Resources Institute
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    • v.2 no.1
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    • pp.103-112
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    • 2006
  • Along with recent improvement of recycling technique, the quality of the recycled concrete aggregate have become very competitive to the natural concrete aggregate. Therefore, a practical use of the recycled concrete aggregate may be possible for structural members. Majority studies about the recycled concrete aggregate was emphasized a limitation of fundamental study concerned with a strength characteristics and durability of the recycled aggregate concrete, there is use for the structural members. Therefore, for the extension of application of recycled concrete aggregate, this investigation verifies the strength characteristics recycled concrete aggregate of the spun-concrete products with various coarse and fine recycled aggregate replacement ratio(coarse recycled aggregate: 0%, 20%, 40%, 60%, 100%; fine recycled aggregate: 0%, 30%, 60%, 100%) and with addition of cellulose fibers(0%, 0.01%, 0.03%, 0.05%, 0.08%). From the test results, The strength of spun concrete used with recycled aggregate [NR specimen], was measured as 72MPa, was found to be very approximately to the strength of spun concrete used with the natural aggregate(NN specimen), was measured as 74MPa, when only fine aggregate was replaced with the recycled. Therefore, the fine recycled concrete aggregate can be successfully used in the spun high strength concrete product. The compressive strength of all specimens used the specialty cellulose fiber were measured as about 70M Pa, however, the increasement of the specialty cellulose fiber content is showed to decrease compressive strength of spun concrete. Therefore, it is anticipated that the specialty cellulose fiber can be applied to the various spun concrete products.

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The Effect of Au Addition on the Hardening Mechanism in Ag-20wt% Pd-20wt% Cu (Ag-20wt% Pd-20wt% Cu 3원합금(元合金) 및 Au첨가합금(添加合金)의 시효경화특성(時效硬化特性))

  • Park, M.H.;Bae, B.J.;Lee, H.S.;Lee, K.D.
    • Journal of Technologic Dentistry
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    • v.19 no.1
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    • pp.21-35
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    • 1997
  • The Ag-Pd-Cu alloys containing a small amount of Au is commonly used for dental purposes, because this alloy is cheaper than Au-base alloys for clinical use. However, the most important characteristic of this alloy is age-hardenability, which is not exhibited by other Ag-base dental alloys. The specimens used were Ag-20Pd-20Cu ternary alloy and Au addition alloy. These alloys were melted and casted by induction electic furace and centrifugal casting machine in Ar atmoshpere. These specimens were solution treated for 2hr at $800^{\circ}C$ and were then quenched into iced water, and aged at $350{\sim}550^{\circ}C$ Age-hardening characteristics of the small Au-containing Ag-pPd-Cu dental alloys were investigated by means of hardness testing, X-ray diffraction and electron microscope observations, electrical resistance, differential scanning calorimetric, emergy dispersed spectra and electron probe microanalysis. Principal results are as follows : Hardening occured in two stages, I. e., stage I in low temperature and stage II in high temperature regions, during continuous aging. The case of hardening in stage I was due to the formation of the Llo type face centered tetragonal PdCu-ordered phase in the grain interior and hardening in stage I was affedted by the Cu concentration. In stage II, decomposition of the $\alpha$ solid solution to a PdCu ordered phase(L1o type) and an Agrich ${\alpha}2$ phase occurred and a discontiunous precipitation occurred at the grain boundary. Form the electron microscope study, it was concluded that the cause of age-hardening in this alloy is the precipitation of the PdCu ordered phase, which has AuCu I type face-centered tetragonal structure. Precipitation procedure was ${\alpha}\to{\alpha}+{\alpha}2+PdCu\to{\alpha}1+{\alpha}2+PdCu$ at Pd/Cu = 1 Ag-Pd-Cu alloy is more effective dental alloy as ageing treatment and is suitable to isothermal ageing at $450^{\circ}C$.

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Tensile Bond Strength of Composite Resin Treated with Er:YAG Laser (Er:YAG 레이저를 활용한 와동형성시 컴포짓 결합강도)

  • Shin, Min;Ji, Young-Duk;Rhu, Sung-Ho;Cho, Jin-Hyoung
    • Journal of Oral Medicine and Pain
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    • v.30 no.2
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    • pp.269-276
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    • 2005
  • This in vitro study evaluated the influence of a flowable composite resin on the tensile bond strength of resin to enamel and dentin treated with Er:YAG laser and diamond bur. 96 Buccal enamel and mid-coronal dentin were laser-irradiated using an Er:YAG laser and treated with diamond bur. Each groups(48) were divided two small groups depends on acid-etching procedure. Light-cure flowable resin(Metafil Flo) and self-cure resin(Clearfil FII New Bond) were used in this study. After surface etching with 37% phosphoric acid and the application of an adhesive system, specimens were prepared with a hybrid composite resin. After 24hours storage in distilled water at 37$^{\circ}C$, all samples were submitted to the tensile bond strength evaluation, using a universal testing machine(Z020, Zwick, Germany). The obtained results were as follows: 1. TBS of acid-etching group were higher than those of non-etching group in both enamel and dentin treated with Er:YAG laser and diamond bur. Laser 'conditioning' was clearly less effective than acid-etching. Moreover, acid etching lased enamel and dentin significantly improved the microTBS of M-Flo. 2. In enamel, TBS of laser-irradiated group were lower than those of bur-prepared group. However, in flowable resin subgroup, there were not differed those between two groups in dentin. 3. In laser-treated group, TBS of flowable composite resin were higher than those of self-curing resin in dentin, however, there was no difference in enamel. From this study, we can conclude that the self- and light-cure composite resin bonded significantly less effective to lased than to bur-cut enamel and dentin, and that acid-etch procedure remains mandatory even after laser ablation. We suggest that Er:YAG laser was useful for preparing dentin cavity with flowable resin filling.

Anti-Inflammatory Effect of Ethanolic Extract from Polyopes affinis through Suppression of NF-κB and MAPK Activation in LPS-Stimulated RAW 264.7 Cells (LPS로 자극된 대식세포에서의 NF-κB와 MAPK 활성 조절을 통한 참까막살(Polyopes affinis) 에탄올 추출물의 항염증 효과)

  • Kim, Min-Ji;Kim, Koth-Bong-Woo-Ri;Park, Sun-Hee;Park, So-Young;Choi, Hyeun-Deok;Choi, Jung-Su;Jang, Mi-Ran;Im, Moo-Hyeog;Ahn, Dong-Hyun
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.46 no.5
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    • pp.537-544
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    • 2017
  • In this study, the anti-inflammatory effect of Polyopes affinis ethanol extract (PAEE) was investigated using LPS-stimulated RAW 264.7 cells and a croton oil-induced ICR mice model. Treatment with PAEE significantly reduced production of nitric oxide (NO) and pro-inflammatory cytokines [interleukin (IL)-6, tumor necrosis factor $(TNF)-{\alpha}$, and $IL-1{\beta}$] in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells. PAEE treatment also reduced expression of inducible NO synthase, cyclooxygenase-2, nuclear $factor-{\kappa}B$, and mitogen-activated protein kinases in LPS-stimulated RAW 264.7 cells. In the croton oil-induced ear edema test, application of PAEE (10~250 mg/kg body weight) reduced ear edema in a dose-dependent manner, and PAEE treatment at 50 mg/kg body weight showed similar inhibitory effects compared with prednisolone (10 mg/kg body weight). Histological analysis revealed reduced dermal thickness and lower number of infiltrated mast cells. These results suggest that PAEE might be used as a promising anti-inflammatory agent for inhibition of LPS-induced inflammation and ear edema formation.

Effects of Total Sleep Deprivation on Fine Motor Performance (전수면박탈이 정상인의 미세운동수행 능력에 미치는 영향)

  • Lee, Heon-Jeong;Song, Hyung-Seok;Ham, Byung-Joo;Suh, Kwang-Yoon;Kim, Leen
    • Sleep Medicine and Psychophysiology
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    • v.8 no.2
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    • pp.129-137
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    • 2001
  • Objectives: The purpose of this study is to investigate the effects of 38-hour sleep deprivation on fine motor performance. The Motor Performance Series (MPS) in the Vienna Test System (computerized neurocognitive function tests) was used in this study. Methods: Twenty four subjects participated in this study. Subjects had no past history of psychiatric disorders and physical illness. Subjects had normal sleep-waking cycle without current sleep disturbances and were all right-handed (Annett's Hand Preference Questionnaire: above +9 points). To minimize the learning effects, familiarization with the Vienna Test System was performed one day before the study. Subjects were to get up at 6:00 in the morning after getting enough sleep according to his or her usual sleep-wake cycle. After awakening, subjects remained awake for 38 hours under continuous surveillance. During two consecutive study days, the subjects tested MPS at 7 AM and 7 PM each day, which means the MPS was done four times in total. During the experiment, anything that could affect the subjects' sleep such as coffee, tea, alcohol, a nap, tiring sports, and all medications were prohibited. Results: In MPS, the fine motor functions of both hands decreased after 38 hours of sleep deprivation. The decrement in motor performance was prominent in the dominant right hand. In the right hand, the total number of tapping was reduced (p<.005), and the number of misses (p<.05) and the length of misses (p<.05) of line tracking, the total length of inserting a short pin (p<.01), the total length of inserting a long pin (p<.05), and the number of misses in aiming (p<.05) increased. Such performance decrement was distinct in the morning sessions. Conclusions: These results suggest that fine motor performance decrement during sleep deprivation is predominant in the right hand, which exerts maximal motor function. The finding of decrement in motor function in tapping during sleep deprivation also suggested that the time required for exhaustion of muscles is shortened during sleep deprivation. More deterioration of motor performance was shown in the morning, which could be explained as circadian rhythm effects.

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The Clinical Characteristics of Diffuse Alveolar Hemorrhage : A Retrospective Study of 21cases (미만성 폐포 출혈의 임상 양상과 예후)

  • Ham, Hyoung-Suk;Roh, Gil-Hwan;Kang, Eun-Hae;Kang, Soo-Jung;An, Chang-Hyeok;Suh, Gee-Young;Chung, Man-Pyo;Kim, Ho-Joong;Kwon, O-Jung;Rhee, Chong-H.
    • Tuberculosis and Respiratory Diseases
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    • v.49 no.5
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    • pp.614-623
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    • 2000
  • Background : Diffuse alveolar hemorrhage (DAH) is rare but often fatal. To determine the clinical manifestations of DAH, its etiology, clinical course and prognosis were studied. Method : A retrospective analysis was performed in 21 patients that were diagnosed as DAH. Diagnosis of DAH was based on the presence of the "classical triad" of hemoptysis, anemia, and rapidly progressive infiltrates on chest X-ray and a finding of bronchoalveolar lavage or lung biopsy. Results : Thirteen patients (61.9%) had collagen vascular diseases (CVDs) as underlying disease and 10 patients had systemic lupus erythematosus. Females were more prevalent in CVD than in non-collagen vascular disease (NCVD). Otherwise, there were no significant differences between the two groups in terms of clinical manifestations. Dyspnea (95.2%), cough (76.2%), hemoptysis (61.9%), and fever (33.0%) were frequent symptoms. The initial creatinine level was higher in CVD than in NCVD ($3.27{\pm}3.15$ mg/dl vs. $1.19{\pm}0.94$ mg/dl, p=0.030). The corresponding drop in hemoglobin level was $2.69{\pm}1.26$ g/dl. Maximal drop in hemoglobin preceded the progression of infiltrates on the chest radiograph by $1.38{\pm}4.22$ days. The mortality rate was higher in the patients with NCVD than in those with CVD (50.0% vs. 23.1%). Conclusion : The DAH can occur not only in patients with CVD but also in those with NCVD. Higher creatinine level CVD in patients is associated with renal involvement in conjunction with DAH. The maximal drop in hemoglobin preceeding the progression of infiltrates on the chest radiograph suggests that the drop in hemoglobin is important for diagnosing DAH.

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Development of a deep-learning based tunnel incident detection system on CCTVs (딥러닝 기반 터널 영상유고감지 시스템 개발 연구)

  • Shin, Hyu-Soung;Lee, Kyu-Beom;Yim, Min-Jin;Kim, Dong-Gyou
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.19 no.6
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    • pp.915-936
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    • 2017
  • In this study, current status of Korean hazard mitigation guideline for tunnel operation is summarized. It shows that requirement for CCTV installation has been gradually stricted and needs for tunnel incident detection system in conjunction with the CCTV in tunnels have been highly increased. Despite of this, it is noticed that mathematical algorithm based incident detection system, which are commonly applied in current tunnel operation, show very low detectable rates by less than 50%. The putative major reasons seem to be (1) very weak intensity of illumination (2) dust in tunnel (3) low installation height of CCTV to about 3.5 m, etc. Therefore, an attempt in this study is made to develop an deep-learning based tunnel incident detection system, which is relatively insensitive to very poor visibility conditions. Its theoretical background is given and validating investigation are undertaken focused on the moving vehicles and person out of vehicle in tunnel, which are the official major objects to be detected. Two scenarios are set up: (1) training and prediction in the same tunnel (2) training in a tunnel and prediction in the other tunnel. From the both cases, targeted object detection in prediction mode are achieved to detectable rate to higher than 80% in case of similar time period between training and prediction but it shows a bit low detectable rate to 40% when the prediction times are far from the training time without further training taking place. However, it is believed that the AI based system would be enhanced in its predictability automatically as further training are followed with accumulated CCTV BigData without any revision or calibration of the incident detection system.

A Comparative Study of Physiological Activity and Ingredient Analysis of Glycyrrhiza uralensis Fischer Stems and Leaves Cultivated with Different Wavelength of LED Lights (LED광원에 따른 감초 지상부의 생리활성 및 성분 평가)

  • Bang, Keuk Soo;Chang, Young Nam;Jin, Jong Sik;Park, Sang A;Lim, Jae Soo;Park, Jeong Sub;Kim, Jong Sung;Lee, Jeong Ho
    • Korean Journal of Plant Resources
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    • v.28 no.1
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    • pp.126-134
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    • 2015
  • Glycyrrhiza uralensis Fischer is one of the most commonly used herbs. Recently, the stem and leave of the plant have been interested in physiological activities because the aerial parts have been thrown away. Finding out cultivation method of Glycyrrhiza uralensis Fischer to improve chemical ingredients and biological activities has been tried these days. In this study, different wavelengths of light emitting diode (LED) were used for a cultivation of Glycyrrhiza uralensis Fischer. Antioxidant activities and inhibitory effect on mutagenecity of samples were evaluated. The stem and leave cultivated under blue light (BL-0) showed the strongest antioxidant activities of $3.02{\pm}0.13{\mu}g/ml$ ($EC_{50}$) and $2.18{\pm}0.18{\mu}g/ml$ ($EC_{50}$) in DPPH and ABTS radical scavenging test, respectively. Total phenolic content of BL-0 was $2.93{\pm}0.11g/100g$, the highest value between cultivation conditions. However, antioxidant activities of the stem and leave cultivated under red light were the weakest between samples. All of the stem and leave used in this study showed inhibitory effect on mutagenecity of 1-nitropyrene. BL-0 showed stronger inhibitory effects on mutagenicity of Trp-P-1, Trp-P-2, and AFB1 than samples cultivated under other conditions. Only on mutagenecity of 2-aminoanthracene, the stem and leave cultivated at 1 m apart from red light (RL-1) showed the strongest inhibitory effect. These results indicate that blue LED might be the most effective condition for improvement of physiological activities for the aerial parts of Glycyrrhiza uralensis Fischer in cultivation. The components were identified with GC/MS. Cytidine was detected only in RL-1 at 25 min of retention time and 2-bromotrimethylene glycol was detected only in BL-0 at 37 min.

The Study of Pain and Pain Management of Cancer Patients (악성종양 환자의 통증 및 통증관리에 관한 연구)

  • Yoon Gwi-Ok;Park Hung-Sook
    • Journal of Korean Academy of Fundamentals of Nursing
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    • v.3 no.2
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    • pp.299-316
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    • 1996
  • This study is the descriptive survey to provide basic data for nursing intervention to pain management of cancer patients by finding more effective way to manage pain with recognize pain level and pain characteristics. To achieve the purpose of this study, the subjects of this study are 110 male or female gastro intestinal tract patients who are older than twenty, are hospitalized in Pusan University Hospital from 1995. 5. 28 to 1995. 9. 25 and have had medical treatment. The modified pain assessment of cancer patients of Cornne, H. Rosermary, M. was used as the tool of study with 16 questionaries. The pain score consists of sensory intensity score and distress score. The data was analyzed by the SPSS statistical program number, percentage, mean, standard deviation, t-test, One Way Anova and Duncan's Multiple Range Test were utilized for analysis. The results were summarized as follows : 1. In population-sociological characteristics : in the age-range of subject, the sixties are most as 32.7% and the subjects after the forties are 89.5%, in sex of subjects, male patients are 66.4% and female 33.6%, in the number of family, the subjects who has 4 or above families are 70% and the subjects who live with their spouse, sons and daughters are 54.5% 2. In the disease characteristics : stomach cancer patients were most as 39.1%. And the most of patient who had never been operated before. In time of pain, the most of subjects were intermittent. In the type of pain, the most of subjects were 'dully pain' as 31.8%. Metastatic subjects were 30.0%. In the origin of pain, nervous pressure was 50.8%. The number of complication was 46 and most of complication are obstruction as 6%. 3. In the pain level, 91subjects complained pain. And mean pain score was $287.1{\pm}116.1$ The mean pain score of female subjects was higher than that of male subjects. 4. In the pain characteristics, the pain began usually at meal time as 40.7%. The duration of pain was mostly from 1 month to 3 months as 57.1%. The appetite was mainly concerned with the pain as 31.8%. The etiology of pain was usually tumor as 69.3%. The meaning of pain was incurable disease as 14.5%, anxiety, death and suffering. 5. The 56(61%) of 91subjects were treated with Analgesic pain management. The kinds of Analgesic is usually valentac as 46.4%. The medication was usually intramuscle as 66.1% at whenever necessary, Response of Analgesic after Medication was usually 'moderate release'. The side effects of medication were nausea as 26.8%. The average amount of morphine dosage hospitalized to cancer patients with pain was 80mg in a day and metastatic cancer patients with pain was 101.9mg in a day. 6. In the relation between the disease characteristics and pain level, there is a significant statistical difference : whether subjects had been operated or not : (t=2.88, p=0.005), time of pain is(t=3.34, p=0.005), stage of metastatic(F=9.323, P=0.0002), and type of pain(F=4.013, p=0.0008). In the pain level of diagnosis, Colon cancer was $353.3{\pm}81.7$(F=2.34, p=0.049), the origin of pain, nerve pressure $316.3{\pm}98.5$(F=2.44, P=0.045), In the complication, ascites and obstruction $324.9{\pm}96.8$(T=2.60, P=0.04).

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Reproductive Ecology and Genetic Variations in the Sea Urchins Anthocidaris crassispina and Hemicentrotus pulcherrimus in the Cheju Coast (제주연안에 서식하는 보라성게 Anthocidaris crassispina와 말똥성게 Hemicentrotus pulcherrimus의 지역별 번식생태학적 특성과 유전적 변이의 비교)

  • 이정재;김범규;강상균;정상철;이기완;최광식
    • Journal of Aquaculture
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    • v.13 no.2
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    • pp.129-135
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    • 2000
  • Genetic variabilities of local populations of Anthocidaris crassispina and Hemicentrotus pulcherrimus were analysed by random amplified polymorphic DNA (RAPD) technique with phenotypic variabilities in timing of gonadal maturation, reproductive output and size of individuals in Cheju. H, pulcherrimus, collected from 4 locations during March 1997, indicated that Daepo individuals were significantly smaller than that at Hamdok, Wimi site A and Wimi site B (ANOVA, p>0.001). Gonodal-somatic index (GSI) of the Wimi site B population was significantly higher than that of three other locations (ANOVA, P>0.0001). An ANOVA test conducted on test size of A. crassispina, harvested from six different locations of Cheju during June 1997, indicated that the size of individuals from Pophwan was significantly smaller (P>0.0001) than that from five other locations. GSIs of urchin m Wimi and Hanlim were significantly higher than that from Pohwan and Oedo (ANOVA, p>0.0001). Genetic similarity, calculated from k13 primer analysis of total DNA, among the six different populations of A. crassispina varied from 0.67 to 0.92, and the values for H. pulcherrimus from 0.60 to 0.73; thus there was no genetic variation among different populations of the same species. Therefore, the populations are genetically homologous and the observed phenotypic variabilities were possibly associated with water temperature and food.

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