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Influencing Factors on Perceived Safety of CCTV among College Students (대학생의 CCTV 체감안전도에 대한 영향 요인)

  • Jin-Hwan Oh
    • Journal of the Korean Applied Science and Technology
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    • v.40 no.4
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    • pp.786-796
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    • 2023
  • The purpose of this study was to examine the influencing factors of perceived safety for CCTV(Closed Circuit Television), and to confirm the correlation between fear of crime, social disorder, physical disorder in the community, and perceived safety for CCTV. Subjects were 140 students from one college located in H city using survey from June 17, 2022 to August 25, 2022. Data was analyzed by descriptive statistics, Pearson's correlation, and Stepwise multiple regression using the SPSS 23.0 program. As a result of the study, fear of crime was correlated with social disorder, physical disorder among community characteristics, and perceived safety of CCTV. Also, social disorder among community characteristics was correlated with physical disorder, perceived safety of CCTV, and physical disorder was correlated with perceived safety of CCTV. The factors affecting perceived safety for CCTV were fear of crime and social disorder, and the explanatory power was 57.2%(Adjusted R2=.572). In conclusion, it is necessary to improve the perceived safety of CCTV by improving the awareness of fear of crime and social disorder.

Estimation on Unsaturated Characteristic Curves of Acid Sulfate Soils (ASS) (산성토의 불포화 특성곡선 산정)

  • Song, Young-Suk
    • The Journal of Engineering Geology
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    • v.28 no.1
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    • pp.25-34
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    • 2018
  • The physical properties and unsaturated characteristics of acid sulfate soils were investigated and analyzed. As the results of measuring physical properties of the acid sulfate soils obtained around the Ilkwang mine area, the dry unit weight is $1.246t/m^3$ and this soil is classified into the silty sand (SM) by USCS. Soil Water Characteristics Curves (SWCC) of the drying and wetting paths were measured by the automated SWCC apparatus. Also, Hydraulic Conductivity Functions (HCF) of the drying and wetting paths were estimated by the van Geunchten (1980) model which is the most well-known parameter estimation method. The hydraulic conductivity of acid sulfate soils in the dry path was continuously decreased with increasing the matric suction. However, the hydraulic conductivity in the wetting path was decreased relatively small with increasing matric suction and decreased suddenly just before water entry value of matric suction. Meanwhile, the hysteresis phenomenon was occurred in SWCCs and HCFs during the drying and wetting paths.

Analysis on Physical and Mechanical Properties of Rock Mass in Korea (국내에 분포하는 암반의 물리·역학적 특성 분석)

  • Seo, Yong-Seok;Yun, Hyun-Seok;Kim, Dong-Gyou;Kwon, O-Il
    • The Journal of Engineering Geology
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    • v.26 no.4
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    • pp.593-600
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    • 2016
  • To understand the mechanical properties of rock masses and intact rock in Korea, data from 4,280 in situ and laboratory tests from 107 tunnels on general national roads were analyzed. The mechanical properties (unit weight, cohesion, friction angle, modulus of deformation, Young's modulus, Poisson's ratio, uniaxial compressive strength, tensile strength, coefficient of permeability, and specific gravity) were analyzed by rock types and strength of rock in each rock type. The results of analysis, the mean specific gravity was highest in gneiss. The coefficient of permeability and Poisson's ratio show the highest mean values in granite and metamorphic rock, respectively. In addition, the unit weight, cohesion and friction angle in sedimentary rock, modulus of deformation, Young's modulus, uniaxial compressive strength and tensile strength in volcanic rock have the highest mean values. The values for each mechanical property showed wide ranges by the heterogeneity and anisotropy of rock masses in spite of detailed analysis by rock type and classification of rocks according to the strength.

The Mechanical Properties of the Geochang Granite (거창화강암의 역학적 특성에 관한 연구)

  • Kim, Myeong Kyun
    • Tunnel and Underground Space
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    • v.25 no.1
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    • pp.24-36
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    • 2015
  • The Geochang granite widely used in construction works is one of the most popular dimension stones in Korea. In order to evaluate the physical properties of rock, a lot of laboratory tests for the Geochang granite were conducted to find unit weight, absorption ratio, P wave velocity, S wave velocity, uniaxial compressive strength, Young's modulus, Poisson's ratio, tensile strength, cohesion, friction angle and point load strength index. The uniaxial compressive strength of the Geochang granite was 19.5 times tensile strength and also 8.6 times cohesion, besides P wave velocity was 1.5 times S wave velocity. Correlation analyses were also conducted to find the correlation among 11 different physical properties, where the uniaxial compressive strength showed Pearson correlation coefficient of more than 0.8 with Poisson's ratio, point load strength index and Young's modulus, respectively. Regression analyses were finally conducted by means of both linear and multiple analysis and the brief results including coefficient of determination of more than 0.7 were presented.

Effects of Inspiratory Muscle Training on Diaphragm Thickness, Pulmonary Function, and Chest Expansion in Chronic Stroke Patients (흡기근 저항훈련이 만성 뇌졸중 환자의 횡격막 두께와 폐기능에 미치는 효과)

  • Jung, Ju-Hyeon;Kim, Nan-Soo
    • Journal of the Korean Society of Physical Medicine
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    • v.8 no.1
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    • pp.59-69
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    • 2013
  • 연구목적: 본 연구는 만성 뇌졸중 환자를 대상으로 흡기근 저항훈련이 횡격막 두께와 폐기능 및 흉곽 확장에 미치는 효과를 알아보고자 수행하였다. 연구방법: 연구 대상자는 총 29명(남자 17명, 여자 12명)으로 흡기근 저항훈련군(15명)과 대조군(14명)으로 분류하였다. 모든 대상자는 6개월 이상된 만성 뇌졸중 환자로 일반적인 신경발달치료를 받고 있으며, 같은 기간 동안 흡기근 저항훈련군에 역치부하 흡기근육 단련기(threshold IMT device)를 제공하고 주 3회${\times}$1회 20분씩 6주간 시행하였다. 마비측과 비마비측 횡격막 두께측정을 위해 초음파의 7.5MHz linear probe를 사용하여 최대 흡기시(Tdi.con)와 휴식시(Tdi.rel)의 두께를 측정하고 수축률(TR)을 계산하였다. 또한 폐 활량계를 사용하여 노력성 폐활량을 측정하였으며, 줄자를 사용하여 흉곽 확장을 측정하였다. 연구결과: 6주간 중재 후 흡기근 저항훈련군에서 최대흡기시 횡격막 두께(Tdi.con)와 수축률(TR)은 유의한 증가를 보였다(p<.05). 1초간 노력성 호기량 ($FEV_1$)과 최대 호기 속도(PEF)도 유의한 증가를 보였으나(p<.05), 노력성 폐활량(FVC)과 1초간 노력성 호기량의 노력성 폐활량에 대한 비($FEV_1$/FVC), 흉곽 확장은 유의한 증가는 보이지 않았다(p>.05). 결론: 본 연구는 만성뇌졸중 환자를 대상으로 흡기근 저항훈련의 적용이 횡격막의 수축력과 폐기능 및 흉곽 확장력을 향상시켜 호흡근의 협응력을 증가시키고, 비활동성으로 인해 감소된 운동내성을 증가하게 함으로써 향후 재활에서 만성 뇌졸중 환자에게 2차적인 기능향상에 도움을 줄수 있을 것으로 보여진다.

The Effect on grasp and pinch strength according to degree of elbow flexion in normal adult (성인의 주관절 굴곡 각도가 파악력과 핀치력에 미치는 영향)

  • Lee, Cu-Rie;Kim, Keun-Jo;Kim, Bonn-Won
    • The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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    • v.14 no.2
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    • pp.25-33
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    • 2008
  • Purpose : This study was investigated the effect on grasp and pinch strength according to degree of flexion in elbow joint. Methods : Thirty male and thirty female students, aged 20 to 31 years were tested for using opened positioning with their shoulder abduction at $55^{\circ}$ and shoulder horizontal adduction at $30^{\circ}$ in four elbow flexion($0^{\circ}$, $45^{\circ}$, $90^{\circ}$, $135^{\circ}$). An electronic dynamometer(E-LINK V900s Evaluation System)and goniometer were used to measure grasp and pinch strength. Results : The average grasp strength of the dominant hand was strongest at elbow $45^{\circ}$ however, weakest at elbow $135^{\circ}$ flexion in both of male and female. The average pinch strength of the dominant hand was strongest at elbow $135^{\circ}$ flexion in both of male and female. The average pinch strength of dominant hand was weakest at elbow $45^{\circ}$ flexion in both of male and female. According to degree of elbow flexion in both of male and female, grasp and pinch strength was no significant statistically. In analyzing correlations, the grasp strength of male showed the most significant difference at elbow $45^{\circ}$ & $90^{\circ}$ flexion, and the pinch strength was most significant difference at elbow $0^{\circ}$ & $45^{\circ}$ flexion. Conclusion : In analyzing correlations, the grasp strength of female showed the most significant difference at elbow $90^{\circ}$ & $135^{\circ}$ flexion, and the pinch strength was most significant difference at elbow $45^{\circ}$ & $90^{\circ}$ flexion.

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Studies on Changes of Carcass Characteristics during Slaughtering Process and Physical Properties of Ostrich Muscles (타조 도축 공정에 따른 도체 특성 변화 및 부위에 따른 타조육의 물리적 특성에 관한 연구)

  • Hong, G.P.;Kim, C.J.;Lee, S.;Min, S.G.
    • Korean Journal of Poultry Science
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    • v.35 no.2
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    • pp.191-196
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    • 2008
  • This study was carried out to investigate the changes in carcass characteristics during slaughter process and to evaluate the physical properties of ostrich muscles. After blooding, pH of carcass was declined rapidly and showed 5.89 of final pH, whilst temperature was slightly decreased during slaughter process. Carcass of ostrich yielded 49.3%. For the comparison between muscles, m. gastrocneminus and m. iliofemoralis externus showed a significantly high pH (P<0.05). The muscle of which pH tended to be high in water holding capacity (WHC), however, m. gastrocneminus showed a significantly low WHC (P<0.05) due to low moisture content. M. obturatorius medialis showed the significantly lower shear force, whilst m. gastrocneminus was higher than other muscles (P<0.05). Therefore the results indicated that the production of high quality carcass was to reduce the time during slaughter process, and that high WHC and tenderness of ostrich meat had a potential application as a substitutional species to other animals.

Physical and Physiological Properties of Isomaltooligosaccharides and Fructooligosaccharides (이소말토올리고당과 프락토올리고당의 물리적 성질 및 생리학적 특성)

  • Kim, Jeong-Ryul;Yook, Cheol;Kwon, Hyuk-Kon;Hong, Sung-Yong;Park, Chan-Koo;Park, Kyung-Ho
    • Korean Journal of Food Science and Technology
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    • v.27 no.2
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    • pp.170-175
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    • 1995
  • Physical and physiological properties of isomaltooligosaccaride (IMO), fructooligosaccharide (FO) and sucrose were investigated. The viscosity and moisture retention power of IMO were similar to those of FO. IMO had an excellent heat and pH stability compared with FO and sucrose. To investigate the effect of oligosaccharides on the growth of mice, each sample was administered orally to mice for 2 weeks. Weight change, moisture content of feces, weight of appendix and the ratio of Bifidobacterium to total microorganisms in the feces were examined. There were no significant differences in the weight increases and the efficiency of feeds. Moisture content of feces was highest in the IMO feeding group, and IMO promoted selectively the growth of Bifidobacterium. On the other hand, FO group showed bigger cecum than other groups.

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Syntheses of the derivatives of chitin and chitosan, and their physicochemical properties (키틴 및 키토산 유도체의 합성과 그 물리화학적 특성)

  • Byun, Hee-Guk;Kang, Ok-Ju;Kim, Se-Kwon
    • Applied Biological Chemistry
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    • v.35 no.4
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    • pp.265-271
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    • 1992
  • Derivatives (microcrystalline chitin, carboxymethylchitin, acetylchitin, N-acetylchitosan, ethylchitosan and chitosansulfate) of chitin and chitosan were synthesized, and the physicochemical properties of the derivatives were compared with those of chitin and chitosan. Carboxymethylchitin was soluble in water or acetic acid, whereas chitosan and ethylchitosan were soluble in acetic acid alone. The water binding capacity of N-acetylchitosan was two fold higher than that of chitin. Lipid binding capacity of carboxymethylchitin was the highest, holding 1800%, and that of chitin was the lowest, holding 511% among the derivatives. Carboxymethylchitin among the derivatives showed the highest emulsifying capacity, however chitin and chitosan didn't produce emulsions. Dye binding capacity of acetylchitin was the highest, holding 0.93 mg dye/g sample (Blue R-250) and 0.96 mg dye/g sample (Red No. 2). It was concluded that carboxymethylchitin is a good emulsifier and N-acetylchitosan, chitosansulfate and chitosan are suitable for use as dye absorbents.

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Rheological Properties of Dough Added with Black Rice Flour (흑미가루를 첨가한 밀가루 반죽의 물리적 특성)

  • Jung, Dong-Sik;Eun, Jong-Bang
    • Korean Journal of Food Science and Technology
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    • v.35 no.1
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    • pp.38-43
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    • 2003
  • The rheological properties of wheat flour and black rice flour dough were investigated in dough added with 0, 10, 20, and 30% of black rice flour (BRF). Increase in BRF concentration resulted in: decreases in protein and gluten contents, whereas ash content increased; decreases in water absorption, stability, development time, elasticity, and valorimeter value of the dough, whereas increase in weakness of the dough, as revealed through farinogram; low initial pasting temperature and temperature at peak viscosity, and decreases in viscosity at peak point and at $94^{\circ}C$, as revealed through amylogram; decreases in extensibility, resistance to extension, and energy, whereas increase in R/E ratio, as revealed through extensogram.