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A Study on Examination of Application in Waste Filled Land and Performance Evaluation as Waterproofing Material by the Spray Water-Soluble Rubber Asphalt (뿜칠형 수용성 고무화 아스팔트 차수재의 성능평가 및 폐기물 매립지 적용성 검토에 관한 연구)

  • 오상근;김형무;정문정;최은수
    • Journal of the Korea Institute of Building Construction
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    • v.1 no.2
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    • pp.165-173
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    • 2001
  • This study examinated the application in construction field and the development of waterproofing material system by the spray water-soluble rubber asphalt to solve the problems of synthetic polymer sheet and gio membrane(A mat sheet of Bentonite) that had been used domestic waterproofing material in advance. As the result of study, characters of study water-soluble rudder asphalt are the follows: 1) The amount of water absorption was '0.06'g and the seepage quality was '0'g in result. 2) The tensile strength was about 30.7kgf/$\textrm{cm}^2 and the elongation was about 72.4% in result. 3) After reliance of temperature test had been ended, the tensile strength was about 72.4kgf/$\textrm{cm}^2 in low temperature and about 30.7kgf/$\textrm{cm}^2 in normal temperature. 4) After acid and alkaline treatment had been ended, the tensile strength was about 19.7kgf/$\textrm{cm}^2$ and about 21.9kgf/$\textrm{cm}^2 in result. 5) After chlorine ion treatment had been ended, the tensile strength was 28.5kgf/$\textrm{cm}^2$ and the elongation was 250% in result. 6) The impact performance was subsided at 1.5m height. 7) After promotion weathering had been ended, the tensile and elongation was about 26.0kgf/$\textrm{cm}^2, 214% in result. So, this study can propose the spray water-soluble rubber asphalt to satisfy the and durability of waste filled land.

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Considerations of Permeability of Converter Slag for Recycling (재활용을 위한 전로슬래그의 투수성 고찰 (I))

  • 이광찬;이문수
    • Journal of the Korean Geotechnical Society
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    • v.15 no.4
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    • pp.69-83
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    • 1999
  • The permeability of converter slag, replacing material of sand mat on improving soft clay foundation, was evaluated in the laboratory. The effects of grain size, flow water time and aging were investigated using sea and fresh water. In the case of converter slag submerged with fresh water, the coefficients of permeability in A and B samples less than 10 mm grain sizes were measured as $6.52\times10^{-2}cm\; per\; sec\; and\; 5.99\times10^{-1}/cm$ per sec respectively, while they were $1.88\times10^{-2}/cm\; per\; sec,\; 3.86\times10^{-1}/cm$ per sec respectively under sea water condition. Also, the condition of turbulent flow may exit and was experimentally identified from the relationship between hydraulic gradient and seepage velocity. After 100 days under sea water condition, the coefficients of permeability of A and B samples decreased ten times than initial values. The reduction of permeability coefficient was considered to result from the filling of voids in high-calcium quicklime(CaO).

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Conservation Scheme and Deterioration States of the Wanggung-ri Five-storied Stone Pagoda in the Iksan, Korea (익산 왕궁리 5층 석탑의 훼손현황과 보존방안 연구)

  • Yang, Hee-Jae;Lee, Chan-Hee;Kim, Sa-Dug;Choi, Seok-Won
    • 보존과학연구
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    • s.25
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    • pp.171-195
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    • 2004
  • This research presents an evaluation of the weathering and deterioration state of the Wanggung-ri five-storied stone pagoda in the Iksan (National Treasure No. 289) and suggests conservational schemes. A deterioration map of the pagoda was drawn from the aspects of petrological, physical, chemical, biological, structural and artificial weathering.The rock properties consisting of the pagoda were medium-grained biotite granite that had leucocratic phenocryst developed in parts. The body of each story suffered severely from the secondary contamination that turned the colors into light grey, pitch dark, yellowish brown, and reddish brown as well as granular decomposition, exfoliation and peel-off. The roof stones were heavy exfoliated or peeled off in most of the cases. In addition to the fine cracks, there were layered cracks on the corners. The roof stones of the3rd and 4th story in the north and west side had some stones fall-off, while those of the 2ndstory in the north side had steel reinforcement filled for a fixing purpose. Those of the 5th story showed big gaps that must have originated from cracks and were easily subject to granular decomposition and rainfall. The inside clay filler was missing in the lower part of the roof stones of the 4th and 5th story and the supporting stones, which were thus covered by light grey or pitch dark sediments. The contact area of the materials was about 70 % in the parts where there was a space due to the filler missing and washigher than 90 % in the lower parts of the pagoda. About 90 % or more of the roof stones surface of each story were covered by aerial plants that formed a thick biological mat. Thus it seemed necessary to come up with the conservational measures to remove the plans living on the surface of the stone materials, with the plans to prevent rain from falling inside, and with the water repellent and hardening treatments to postpone the surface weathering of the rock properties. All those measures and plans must be based on the results of long-term monitoring and thorough detail investigations.

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Code synchronization technique for spread spectrum transmission based on DVB-RCS +M standard (DVB-RCS +M 표준기반의 대역확산기술 부호동기기법)

  • Kim, Pan-Soo;Chang, Dae-Ig;Lee, Ho-Jin
    • Journal of Satellite, Information and Communications
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    • v.4 no.2
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    • pp.39-45
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    • 2009
  • This paper proposes the specific code synchronization technique for DS-SS(Direct Sequence-Spread Spectrum transmission in the DVB-RCS +M standard. DS-SS is better than multi-carrier transmission method under nonlinear channel but imposes a long acquisition time. To improve the synchronization aspect, the robust correlation structure is introduced for acquisition and the nonlinear delay lock loop is done for tracking. MAT(Mean Acquisition Time) performances is shown to validate its superiority. In addition, code tracking and jitter performances are done when code tracking algorithm based on 2 oversamples which is not influenced by sampling clock timing offset and carrier freq. offset is used.

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Finite Element Analysis for Transmission Tower Behavior Characteristic by Connection Beam Stiffness (수치해석을 이용한 송전철탑 연결형 기초의 연결보 강성에 따른 거동 특성)

  • Choi, YoungHo;Kyung, DooHyun;Lee, JunHwan
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.33 no.1
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    • pp.219-227
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    • 2013
  • This study analyzed the effect of performance connected-type foundations of behavior and the connected beams according to the characteristics into soft clay transmission tower foundation. For this purpose, the finite element analysis model was built and connected to the transmission tower foundation mat and the contact area of the connection beam by the percentage change in the behavior and resistance characteristics were analyzed and finite element verification of the validity of the analytical model was conducted using connected-type transmission tower results of the model experiments constructed, and effective connected-type transmission tower basis of the behavior of connected beams were selected by analyzing the effect due to the increase of the stiffness. In addition, weak analysis by connected beam self-bending moment distribution was conducted.

The Effect of Submerged Relaxation Exercise on Muscle Tone in Persons With Hemiparesis (수중이완운동이 편마비 환자의 근긴장도에 미치는 영향)

  • Chun, Seung-Chul;Yoon, Seoung-Ic;Oh, Duck-Won;Shim, Jae-Hun;Lee, Gyu-Wan;An, Chang-Sik
    • Physical Therapy Korea
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    • v.13 no.3
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    • pp.84-91
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    • 2006
  • The purpose of this study was to investigate the effect of submerged relaxation therapy for the spasticity on the affected side in three subjects with post-stroke hemiparesis. A single-subject alternating design with multiple baselines across individuals was employed in this study. Each subject alternately participated in a range of motion exercises on the mat and in the pool, and relaxation exercises in the pool. The muscle tone of the affected side was measured using the tone assessment scale (TAS). Measurements were made immediately and one hour following the intervention. The findings showed a therapeutic effect of submerged relaxation exercise on reducing spasticity for all subjects. The effect of submerged relaxation exercise on decreasing muscle tone was maintained for one hour measurements after the submerged relaxation exercise, although the mean TAS score assessed one hour after intervention was higher than that assessed immediately. The results of this study suggest that submerged relaxation exercise has a positive effect on decreasing spasticity on the affected side in persons suffering from post-stroke hemiparesis. Future research on submerged relaxation exercise should focus on objective evaluation and functional the aspects relevant to activities of daily living.

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Evaluation of the Functional and Non-functional Seat Sponge Effect in Sitting Chairs

  • Min, Seung Nam;Park, Se Jin;Subramaniyam, Murali;Lee, Heeran
    • Journal of the Ergonomics Society of Korea
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    • v.33 no.4
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    • pp.255-265
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    • 2014
  • Objective: The purpose of this study was to evaluate comfort levels of functional and non-functional chairs using subjective comfort rating, interface pressure measurement, muscle activity measurement, and skin temperature measurement. Background: Chairs are used for a prolonged period of time for sitting in many places such as the office, at university, at school, in industry, and so on. Almost all people use chairs in their everyday life. The functional properties of the chair are associated with comfort. Method: The subjective evaluation contains questions regarding chair comfort which can be rated with five point scale. The body-seat interface pressure was measured using a pressure mat system. The symmetry of sitting was measured using electromyography. The change in body part (thigh and buttock) temperature before and after sitting on a chair was measured with an infrared camera. Results: Participants rated significantly (p < 0.05) higher comfort scores for the functional chair in relation to the buttock and thigh region. Also, the participants felt a better cushion effect in the functional chair. When using the functional chair, lower interface pressure, better thermal comfort, and better symmetry of erector spinae muscle activity were observed. Conclusion: Overall, interface pressure measurement, muscle activity measurement, thermal imaging and subjective comfort score results showed that the functional chair was more comfortable than the non-functional chair. Application: The adopted methodologies could be used to measure the seating comfort of train seats.

Identification of Cryptosporidium from Dairy Cattle in Pahang, Malaysia

  • Hisamuddin, Nur Hazirah;Hashim, Najat;Soffian, Sharmeen Nellisa;Amin, Mohd Hishammfariz Mohd;Wahab, Ridhwan Abdul;Mohammad, Mardhiah;Isa, Muhammad Lokman Md;Yusof, Afzan Mat
    • Parasites, Hosts and Diseases
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    • v.54 no.2
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    • pp.197-200
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    • 2016
  • Cryptosporidium, a protozoan parasite, can cause cryptosporidiosis which is a gastrointestinal disease that can infect humans and livestock. Cattle are the most common livestock that can be infected with this protozoan. This study was carried out to determine the prevalence of Cryptosporidium infection in cattle in Kuantan, Pahang, Malaysia and to find out the association between the occurrence of infection and 3 different ages of cattle (calves less than 1 year, yearling, and adult cattle). The samples were processed by using formol-ether concentration technique and stained by modified Ziehl Neelsen. The results showed that 15.9% (24/151) of cattle were positive for Cryptosporidium oocysts. The occurrence of Cryptosporidium in calves less than 1 year was the highest with the percentage of 20.0% (11/55) followed by yearling and adult cattle, with the percentage occurrence of 15.6 % (7/45) and 11.8% (6/51), respectively. There was no significant association between the occurrence and age of cattle and presence of diarrhea. Good management practices and proper hygiene management must be taken in order to reduce the infection. It is highly important to control the infection since infected cattle may serve as potential reservoirs of the infection to other animals and humans, especially animal handlers.

Identification of Marker Nucleotides for the Molecular Authentication of Arisaematis Rhizoma Based on the DNA Barcode Sequences (천남성(天南星) 유전자 감별을 위한 DNA 바코드 분석 및 Marker Nucleotide 발굴)

  • Kim, Wook Jin;Lee, Young Mi;Ji, Yunui;Kang, Young Min;Choi, Goya;Kim, Ho Kyoung;Moon, Byeong Cheol
    • The Korea Journal of Herbology
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    • v.29 no.6
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    • pp.35-43
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    • 2014
  • Objectives : Official Arisaematis Rhizoma is described only three species, Arisaema amurnse, Arisaema erubescens, and Arisaema heterophyllum, in national Pharmacopoeia. However, other Arisaema species, Arisaema ringens, Arisaema takesimense and Arisaema serratum, also have been distributed as an inauthentic Arisaematis Rhizoma in the herbal market. To develop a reliable molecular authentication method for Arisaematis Rhizoma in species level, we analyzed DNA barcode regions using six Arisaema species. Methods : Thirty-eight samples of six Arisaema plants species (A. amurense, A. amurense f. serratum, A. heterophyllum, A. takesimense, and A. serratum) were collected from different habitate and nucleotide sequences of DNA barcode regions (rDNA-ITS, matK, and rbcL gene) were analyzed after PCR amplification. The species-specific sequences and phylogenetic relations were estimated using entire sequences of three DNA barcodes based on the analysis of ClastalW and UPGMA, respectively. Results : The comparative analysis of DNA barcode sequences were revealed inter-species specific nucleotides to distinguish the medicinal plant of Arisaema Rhizoma in species levels excluding between A. amurense and its subspecies (A. amurense f. serratum) and A. takesimense and A. serratum, respectively. However, we obtained sequence differences enough to discriminate authentic and inauthentic Arisaematis Rhizoma. Therefore, we suggest that these SNP type molecular genetic markers were an reliable method avaliable to identify official herbal medicines. Conclusions : These marker nucleotides could be useful to identify the official herbal medicines by providing definitive information that can identify original medicinal plant and distinguish from inauthentic adulterants and substitutes.

Structure and Change Pattern of Gijang Mountain Fortress and its Receiving Reservoir (기장산성 집수지의 구조와 변화양상)

  • Hwang, Dae-Il;Jung, Dae-Bong;Park, Jun-Hyun
    • Journal of architectural history
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    • v.22 no.4
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    • pp.35-44
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    • 2013
  • This paper looked into the structure of and changes in the building process of Gijang mountain fortress and its receiving reservoir by analyzing data from an excavation investigation. The structure of the receiving reservoir may be classified into a flat form, stone sheath, floor facility, wall facility, and entry and exit facility. The flat form of the Gijang mountain fortress and receiving reservoir is round. Concerning the sectional form, the wall was obliquely excavated in the trapezoid. As a stone sheath building method, it was built by undertaking a range work of oblong stone materials in a clockwise direction on a stamped soil floor. Then, it was treated with stamping using double layers of gray clay and yellowish brown clay on the floor and the wall. Also, in a space between the stamped layers on the floor, herbal plants and a straw mat were laid for waterproofing as well as to prevent sinking. As an entry and exit facility, two facilities were confirmed symmetrically in the southeast and in the northwest. It is believed that they were built additionally during rebuilding after the initial construction. The building process was revealed to have been carried out in 8 stages. Given the structure and excavated remains, the building period is estimated to be the early to mid 7th century for the initial building, the later 9th to 11th centuries for the primary rebuilding, and the later 16th to early 17th centuries for the secondary rebuilding.