Journal of the Korean Society of Fisheries and Ocean Technology
/
제18권1호
/
pp.17-23
/
1982
The corrosion loss of the shell plates and the bulkead plates of the oil tankers, nationalities of which belong to korea are determined and analyzed. The thickness of the plates are determined by use of the ultrasonic thickness meters at the check points set along the fore and aft line and the perpendicular to it. Difference between the original thickness and the determined one are given as the corrosion loss at the present age. 1. On the shell plates (1) The total mean of the corrosion loss shows the greatest value on the load water line in every age classes of the vessels. (2) The total mean of the corrosion loss on the fore and aft line shows little difference, even though it is slightly greater at the fore part, in every age classes of the vessels. (3) The corrosion loss along the perpendicular grows greater in the order of upper bilge line, light water line, freeboard line and load water line at 16 ages of the vessels, and the loss changes in the order of light water line, upper bilge line, freeboard line and load water line at 20 ages of the vessels. (4) The total mean of the corrosion loss along the light water line and upper and lower water line shows the greatest value on the fore part. That along the freeboard line and the load water line shows the greatest value on the midship part and on the after part, respectively. 2. On the bulkhead plates (1) The total mean of the corrosion loss shows the greatest value on the top part at the every age classes of the vessels. (2)The corrosion loss along the perpendicular grows greater in the order of the lower, center and upper part at every age classes of the vessels. (3) The total mean of the corrosion loss at the top part grows greater in the order of the transverse bulkhead of the side oil tank, that of center oil tank, longitudinal bulkhead of center oil tank, and transverse bulkhead of side water tank at the 20 ages of the vessels.
Purpose: Childhood obesity is an increasing public health issue worldwide. We examined dietary patterns among adolescents in a dormitory school, identified obese adolescents and tried to intervene to improve food habits and physical activity. Methods: We conducted an experimental prospective longitudinal study based on 36 obese (body mass index $[BMI]{\geq}95th$ percentile) adolescents (aged 12-18 years) compared with controls (healthy children: normal age-appropriate BMI ($BMI{\leq}85th$ percentile). Six months' intervention included lifestyle-modification counseling (once a week by a clinical dietician), and an exercise regimen twice a week, 60 minutes each time, instructed by a professional pediatric trainer). Both groups underwent baseline measurements at the beginning of the study and 6 months later (arterial stiffness, blood pressure, pulse, weight and height, hemoglobin, creatinine, liver enzymes, highly sensitive C-reactive protein and complete lipid profile). Results: Twenty-one participants completed the study. Low compliance from participants, school staff and parents was observed (participation in planned meetings; 71%-83%). BMI significantly decreased from $32.46{\pm}3.93kg/m^2$ to $30.32{\pm}3.4kg/m^2$ (P=0.002) in the study group. Arterial stiffness was not significantly different between the 2 groups and did not change significantly after 6 months' intervention (P=0.494). No significant changes in CRP and lipid profile were observed after the intervention. Conclusion: Making lifestyle modifications among adolescents in a dormitory school is a complex task. Active intervention indeed ameliorates BMI parameters. However, in order to maximize the beneficial effects, a multidisciplinary well-trained team is needed, with emphasis on integrating parents and the school environment.
Cracking is an inevitable fact of asphalt concrete pavements and plays a major role in pavement deterioration. Pavement cracking is one of the main factors determining the frequency and method of repair. Cracks can be treated with a number of preventative maintenance actions, including overlay surface treatments such as slurry sealing, crack sealing, or crack filling. Pavement cracks can show up as one or all of the following types: transverse, longitudinal, fatigue, block, reflective, edge, and slippage. Crack sealing is a frequently used pavement maintenance treatment because it significantly extends the pavement service life. However, crack sealant often fails prematurely due to a loss of adhesion. Because current test methods are mostly empirical and only provide a qualitative measure of the bond strength, they cannot accurately predict the adhesive failure of the sealant. This study introduces a laboratory test aimed at assessing the bonding of hot-poured crack sealant to the walls of pavement cracks. A pneumatic adhesion tensile testing instrument (PATTI) was adopted to measure the bonding strength of the hot-poured crack sealant as a function of the curing time and temperature. Based on a limited number of test results, the hot-poured crack sealants have very different bonding performances. Therefore, this test method can be proposed as part of a newly developed performance-based standard specification for hot-poured crack sealants for use in the future. PURPOSES : The purpose of this study was to evaluate both the adhesion and failure performance of a crack sealant as a function of its curing time and curing temperature. METHODS: A pneumatic adhesion tensile testing instrument (PATTI) was adopted to measure the adhesion performance of a crack sealant as a function of the curing time and curing temperature. RESULTS: With changes in the curing time, curing temperature, and sealant type, the bond strengths were found to be significantly different. Also, higher bond strengths were measured at lower temperatures. Different sealant types produced completely different bond strengths and failure behaviors. CONCLUSIONS: The bonding strength of an evaluated crack sealant was shown to differ depending on various factors. Two sealant types, which were composed of different raw materials, were shown to perform differently. The newly proposed test offers the possibility of evaluating and differentiating between different crack sealants. Based on alimited number of test results, this test method can be proposed as part of a newly developed performance-based standard specification for crack sealants or as part of a guideline for the selection of hot-poured crack sealant in the future.
Hwang, Hyeon-Shik;Kim, Wang-Sik;Kim, Jeong-Moon;Mcnamara, James A. Jr.
The korean journal of orthodontics
/
제40권1호
/
pp.34-39
/
2010
Objective: The aim of the present study was to evaluate the changes in tooth mobility following orthodontic treatment and to obtain information regarding the guideline of retainer wear duration during the post-treatment period. Methods: The sample consisted of twenty patients who had been treated with edgewise appliances. The mobility of the maxillary teeth from the central incisor to the first molar was measured bilaterally by way of the $Periotest^{(R)}$, a non-invasive, electronic device that provides an objective measurement of the reaction of the periodontium to a defined impact load. Tooth mobility was monitored at the time of the removal of the orthodontic appliances and subsequently at three-month intervals during the two years following appliance removal. Results: Tooth mobility decreased rapidly for the first six months and then decreased at a slower rate during the next six months; no statistically significant decrease in mobility was observed during the second year following appliance removal. Conclusions: The results of the present study suggest that adequate tooth stabilization is critical during the first six months following appliance removal and that continued wearing of retainers is recommended at least until twelve months after the completion of orthodontic treatment.
In this study, fish fauna and stream characteristics were surveyed from June to October of 2014 in 31 sites of 23 small streams of Namhae Island. During the study period, 38 species belonging to 30 genera under 13 families were collected. Cyprinidae and Gobiidae fish occupied 28.9% (11 species) and Cobitidae fish accounted for 10.5% (4 species). The dominant family was Cyprinidae, and the most dominant species was Zacco koreanus with 30.3% (1,089 individuals) of the total. Eight species (33.8%) such as Zacco koreanus, Squalidus gracilis majimae, Coreoleuciscus splendidus, Pseudobagrus koreanus, Iksookimia hugowolfeld, Iksookimia longicorpa, Silurus microdorsalis and Liobagrus mediadiposalis were Korean endemic and one species of Micropterus salmoides was exotic. According to the analysis of the community based on the diversity, evenness and richness indices, fish community seems to be more stable in the S7. The small streams were classified into three types of steep mountainous, mountainous-flatland, and flat land streams, and their types were categorized by their features of stream width, water depth, bottom substrate, riparian vegetation, and land use patterns. Principal component analysis based on species abundance classified fish communities into three main groups according to human impact and land-use pattern change. These results suggest that fish community structures were primary affected by the longitudinal environmental changes and these were modified by the habitat condition in accordance with the land use pattern change in the small streams.
In general, women's labor force participation follows a M-curve pattern because women's state of economic activity usually changes by their life course stage. This research attentions that the effect of sequence of life course as well as the effects of‘marriage bar’, or‘maternity leave’is very important in understanding women's chaning economic activity status. First, this research hypothesizes that women's four patterns of job career such as‘continuous pattern’,‘discontinuous pattern’,‘non-economic activity pattern’,‘marriage leave pattern’result a significant difference in social and demographic variables. Second, this research analyzes the effect of ordering and timing of life events on women's work transition. This research investigates labor market dynamics to conceptualize labor market behaviors using longitudinal data and sequence analysis and event history analysis. We find that four patterns of job career vary by age, educational attainment, having a certificate or not, their parents’human capital and health status. And we find that the ordering and timing of‘participation in labor market’and‘marriage’determine the pattern of women's work transition.
In this study, Echo-sounder($E_s$) monitoring methodology was applied to test environmental impacts of artificial weirs(SCW and JSW) in the Yeongsan River on fish community and habitat structures at first time, and was compared with conventional fish sampling methodologies($C_s$). For the Es monitoring in the fields, parallel transect methods was employed in determining the survey distance interval with every 125 m within the upper-lower 2 km of the weirs. Four different fish sampling gears such as casting nets, kick nets, fyke nets, and gill nets were used for applications of $C_s$ monitoring methodology. According to the Echo-sounder monitoring, fish density, expressed as a number of individuals per square meter, along the longitudinal axis of the weir was significantly greater(JSW, t = 3.506, n = 30, p < 0.001) in the down-river reach of the weir than in the up-river reach. Also, fish density along the vertical water column was highest at mid-depths of Seungchon weir, which has simple habitat substrates, while fish density was highest at hypolimnetic depth of Juksan weir. According to fish sampling by the $C_s$ methodology, the fish compositions decreased as the river goes upward, and significant differences(JSW, t = 0.248, n = 30, p < 0.05) in the compositions of fish species occurred between up-reach and down-reach of the weirs. The dominant species near the two weirs were Opsarichthys uncirostris amurensis, Hemiculter eigenmanni and Coilia nasus. Overall, our fish and habitat data, based on $E_s$ and $C_s$ monitoring methodologies, suggest that the weirs disturbed the rivers due to initial habitat disturbances by the weir constructions as well as the barrier roles of weirs on fish passage and migrations. More long-term scientific and systematic fish impact monitoring and assessments($E_s$ and $C_s$) are required in the future to predict changes of ecological structures and functions on the constructions of the weirs.
Transactions of the Korean Society for Noise and Vibration Engineering
/
제14권6호
/
pp.528-535
/
2004
Ultrasonic Vibrator is designed to achieve the maximum vibration amplitude at 30 kHz by in-cluding a horn (diameter, 40 mm), mechanical vibration amplifier at the top of the ultrasonic vibrator in the system and making the complete system resonate. In addition, it is experimentally visualized by particle imaging velocimetry (PIV) that the acoustic streaming velocity in the gap is at maximum when the gap between the ultrasonic vibrator and stationary plate agrees with the multiples of half-wavelength of the ultrasonic wave. This fact results from the resonance of the sound wave and the theoretical analysis of that is also accomplished and verified by experiment. It is observed that the magnitude of the acoustic streaming dependent upon the gap between the ultrasonic vibrator and stationary plate possibly changes due to the measurement of the average velocity fields of the acoustic streaming induced by the ultrasonic vibration at resonance and non-resonance. There exists extremely small average velocity at non-resonant gaps while the relatively large average velocity exists at resonant gaps compared with non-resonant gaps. It also reveals that there should be larger axial turbulent intensity at the hub region of the vibrator and at the edge of it in the resonant gap where the air streaming velocity is maximized and the flow phenomena is conspicuous than that at the other region. Because the variation of the acoustic streaming velocity at resonant gap is more distinctive than that at non-resonant gap, shear stress increases more in the resonant gap and is also maximized at the center region of the vibrator except the local position of center (r〓0). At the non-resonant gap there should be low values of vorticity distribution, but in contrast to the non-resonant gap, high and negative values of it exist at the center region of the vibrator with respect to the radial direction and in the vicinity of the middle region with respect to the axial direction. Acoustic streaming is noise-free due to the ultrasonic vibration and maintenance-free because of the absence of moving parts. Moreover, the proposed method by acoustic streaming can be utilized to the nano and micro-electro mechanical systems as a driving mechanism in addition to the augmentation of the streaming velocity.
Japan has remained a welfare laggard among advanced industrial democracies. Therefore, the introduction of the public long-term care insurance(koteki kaigo hoken in Japanese) in April of 2000 looks very unique in terms of the Japanese social security tradition, because it can be interpreted as the expansion of social security system and the weakening of the market power over the livelihood of the ordinary people. In the era of globalization, in which even the highly developed welfare states are forced to shrink their social security systems, Japan, a welfare laggard, looks like being headed to the opposite direction. This article aims to define the character of the public long-term care insurance, and thereby, to evaluate the recent social policy of the Japanese government. This study follows the social democratic model in the study of the welfare state development, which assumes that, under the condition of a weak social democratic party and a fragmented labor movement, the introduction of the long-term care insurance is not equal to the improvement of the Japanese social security system. The main argument of this article is that the long-term care insurance, notwithstanding its appearance as an expansion of public sphere, is part of market-oriented neo-liberal social reforms, which have remained the main feature of the Japanese social policies since the mid-1970's. For this, this study will do a longitudinal analysis on the social consequences of the long-term care insurance incurred to the Japanese social security system for the long-term care, focusing on the income redistribution, the marketization of long-term care sector and the changes in the financial burden of the government, social insurers and general citizens.
Mobile technology is accelerating innovative changes across all fields of our society as well as business environments. Especially, demands on mobile government (M-government) services have been increased gradually since e-government has improved national administration services dramatically. However, high-quality services which are acceptable to may users are not actually supplied because technical issues such as security on mobile e-government services have not solved and governance policy was not established yet. Previous studies show that most researches are devoted to technical ones or limited to theoretical exploratory study. As a result, developing useful guidelines which are practically and theoretically proved is one of the very important research issues. This study reviews the previous research works such as concept of mobile, e-government, M-government, technical trends of mobile, market situations, present status, and various case studies. And then we develop a research model with five factors, twenty four variables and seventy six measurement for measuring the influencing factors to adoption of M-government services. The model is composed of total 16 hypotheses, 22 variables, and 76 measurements. The model is analyzed by using statistical package SPSS (18.0) and AMOS (18.0) together with structural equation method based on 294 samples. The results show that the model is valid and there are statistically significant influence between ease of use and usefulness, ease of use and user's satisfactions, usefulness and intent of re-use, and user's satisfactions and intent of re-use, excepting usefulness and user's satisfaction, ease of use and intent of re-use did not affect significant influences. Especially, service quality, system quality, and relationship quality are identified as influencing factors to adaption of M-government service. The results are expected to provide a theoretical research framework which generate new research issues in M-government service area. It also can provide an useful guidelines to practical experts in successfully implementing M-government services. Further research directions are as follows. User's intents have to be studied in details by classifying users by individual, enterprise, and government as well as developing a new hypothetical model. Since M-government service is at the initial stage, longitudinal studies have to be conducted to trace the peoples' need in order to develop new high-quality mobile services.
본 웹사이트에 게시된 이메일 주소가 전자우편 수집 프로그램이나
그 밖의 기술적 장치를 이용하여 무단으로 수집되는 것을 거부하며,
이를 위반시 정보통신망법에 의해 형사 처벌됨을 유념하시기 바랍니다.
[게시일 2004년 10월 1일]
이용약관
제 1 장 총칙
제 1 조 (목적)
이 이용약관은 KoreaScience 홈페이지(이하 “당 사이트”)에서 제공하는 인터넷 서비스(이하 '서비스')의 가입조건 및 이용에 관한 제반 사항과 기타 필요한 사항을 구체적으로 규정함을 목적으로 합니다.
제 2 조 (용어의 정의)
① "이용자"라 함은 당 사이트에 접속하여 이 약관에 따라 당 사이트가 제공하는 서비스를 받는 회원 및 비회원을
말합니다.
② "회원"이라 함은 서비스를 이용하기 위하여 당 사이트에 개인정보를 제공하여 아이디(ID)와 비밀번호를 부여
받은 자를 말합니다.
③ "회원 아이디(ID)"라 함은 회원의 식별 및 서비스 이용을 위하여 자신이 선정한 문자 및 숫자의 조합을
말합니다.
④ "비밀번호(패스워드)"라 함은 회원이 자신의 비밀보호를 위하여 선정한 문자 및 숫자의 조합을 말합니다.
제 3 조 (이용약관의 효력 및 변경)
① 이 약관은 당 사이트에 게시하거나 기타의 방법으로 회원에게 공지함으로써 효력이 발생합니다.
② 당 사이트는 이 약관을 개정할 경우에 적용일자 및 개정사유를 명시하여 현행 약관과 함께 당 사이트의
초기화면에 그 적용일자 7일 이전부터 적용일자 전일까지 공지합니다. 다만, 회원에게 불리하게 약관내용을
변경하는 경우에는 최소한 30일 이상의 사전 유예기간을 두고 공지합니다. 이 경우 당 사이트는 개정 전
내용과 개정 후 내용을 명확하게 비교하여 이용자가 알기 쉽도록 표시합니다.
제 4 조(약관 외 준칙)
① 이 약관은 당 사이트가 제공하는 서비스에 관한 이용안내와 함께 적용됩니다.
② 이 약관에 명시되지 아니한 사항은 관계법령의 규정이 적용됩니다.
제 2 장 이용계약의 체결
제 5 조 (이용계약의 성립 등)
① 이용계약은 이용고객이 당 사이트가 정한 약관에 「동의합니다」를 선택하고, 당 사이트가 정한
온라인신청양식을 작성하여 서비스 이용을 신청한 후, 당 사이트가 이를 승낙함으로써 성립합니다.
② 제1항의 승낙은 당 사이트가 제공하는 과학기술정보검색, 맞춤정보, 서지정보 등 다른 서비스의 이용승낙을
포함합니다.
제 6 조 (회원가입)
서비스를 이용하고자 하는 고객은 당 사이트에서 정한 회원가입양식에 개인정보를 기재하여 가입을 하여야 합니다.
제 7 조 (개인정보의 보호 및 사용)
당 사이트는 관계법령이 정하는 바에 따라 회원 등록정보를 포함한 회원의 개인정보를 보호하기 위해 노력합니다. 회원 개인정보의 보호 및 사용에 대해서는 관련법령 및 당 사이트의 개인정보 보호정책이 적용됩니다.
제 8 조 (이용 신청의 승낙과 제한)
① 당 사이트는 제6조의 규정에 의한 이용신청고객에 대하여 서비스 이용을 승낙합니다.
② 당 사이트는 아래사항에 해당하는 경우에 대해서 승낙하지 아니 합니다.
- 이용계약 신청서의 내용을 허위로 기재한 경우
- 기타 규정한 제반사항을 위반하며 신청하는 경우
제 9 조 (회원 ID 부여 및 변경 등)
① 당 사이트는 이용고객에 대하여 약관에 정하는 바에 따라 자신이 선정한 회원 ID를 부여합니다.
② 회원 ID는 원칙적으로 변경이 불가하며 부득이한 사유로 인하여 변경 하고자 하는 경우에는 해당 ID를
해지하고 재가입해야 합니다.
③ 기타 회원 개인정보 관리 및 변경 등에 관한 사항은 서비스별 안내에 정하는 바에 의합니다.
제 3 장 계약 당사자의 의무
제 10 조 (KISTI의 의무)
① 당 사이트는 이용고객이 희망한 서비스 제공 개시일에 특별한 사정이 없는 한 서비스를 이용할 수 있도록
하여야 합니다.
② 당 사이트는 개인정보 보호를 위해 보안시스템을 구축하며 개인정보 보호정책을 공시하고 준수합니다.
③ 당 사이트는 회원으로부터 제기되는 의견이나 불만이 정당하다고 객관적으로 인정될 경우에는 적절한 절차를
거쳐 즉시 처리하여야 합니다. 다만, 즉시 처리가 곤란한 경우는 회원에게 그 사유와 처리일정을 통보하여야
합니다.
제 11 조 (회원의 의무)
① 이용자는 회원가입 신청 또는 회원정보 변경 시 실명으로 모든 사항을 사실에 근거하여 작성하여야 하며,
허위 또는 타인의 정보를 등록할 경우 일체의 권리를 주장할 수 없습니다.
② 당 사이트가 관계법령 및 개인정보 보호정책에 의거하여 그 책임을 지는 경우를 제외하고 회원에게 부여된
ID의 비밀번호 관리소홀, 부정사용에 의하여 발생하는 모든 결과에 대한 책임은 회원에게 있습니다.
③ 회원은 당 사이트 및 제 3자의 지적 재산권을 침해해서는 안 됩니다.
제 4 장 서비스의 이용
제 12 조 (서비스 이용 시간)
① 서비스 이용은 당 사이트의 업무상 또는 기술상 특별한 지장이 없는 한 연중무휴, 1일 24시간 운영을
원칙으로 합니다. 단, 당 사이트는 시스템 정기점검, 증설 및 교체를 위해 당 사이트가 정한 날이나 시간에
서비스를 일시 중단할 수 있으며, 예정되어 있는 작업으로 인한 서비스 일시중단은 당 사이트 홈페이지를
통해 사전에 공지합니다.
② 당 사이트는 서비스를 특정범위로 분할하여 각 범위별로 이용가능시간을 별도로 지정할 수 있습니다. 다만
이 경우 그 내용을 공지합니다.
제 13 조 (홈페이지 저작권)
① NDSL에서 제공하는 모든 저작물의 저작권은 원저작자에게 있으며, KISTI는 복제/배포/전송권을 확보하고
있습니다.
② NDSL에서 제공하는 콘텐츠를 상업적 및 기타 영리목적으로 복제/배포/전송할 경우 사전에 KISTI의 허락을
받아야 합니다.
③ NDSL에서 제공하는 콘텐츠를 보도, 비평, 교육, 연구 등을 위하여 정당한 범위 안에서 공정한 관행에
합치되게 인용할 수 있습니다.
④ NDSL에서 제공하는 콘텐츠를 무단 복제, 전송, 배포 기타 저작권법에 위반되는 방법으로 이용할 경우
저작권법 제136조에 따라 5년 이하의 징역 또는 5천만 원 이하의 벌금에 처해질 수 있습니다.
제 14 조 (유료서비스)
① 당 사이트 및 협력기관이 정한 유료서비스(원문복사 등)는 별도로 정해진 바에 따르며, 변경사항은 시행 전에
당 사이트 홈페이지를 통하여 회원에게 공지합니다.
② 유료서비스를 이용하려는 회원은 정해진 요금체계에 따라 요금을 납부해야 합니다.
제 5 장 계약 해지 및 이용 제한
제 15 조 (계약 해지)
회원이 이용계약을 해지하고자 하는 때에는 [가입해지] 메뉴를 이용해 직접 해지해야 합니다.
제 16 조 (서비스 이용제한)
① 당 사이트는 회원이 서비스 이용내용에 있어서 본 약관 제 11조 내용을 위반하거나, 다음 각 호에 해당하는
경우 서비스 이용을 제한할 수 있습니다.
- 2년 이상 서비스를 이용한 적이 없는 경우
- 기타 정상적인 서비스 운영에 방해가 될 경우
② 상기 이용제한 규정에 따라 서비스를 이용하는 회원에게 서비스 이용에 대하여 별도 공지 없이 서비스 이용의
일시정지, 이용계약 해지 할 수 있습니다.
제 17 조 (전자우편주소 수집 금지)
회원은 전자우편주소 추출기 등을 이용하여 전자우편주소를 수집 또는 제3자에게 제공할 수 없습니다.
제 6 장 손해배상 및 기타사항
제 18 조 (손해배상)
당 사이트는 무료로 제공되는 서비스와 관련하여 회원에게 어떠한 손해가 발생하더라도 당 사이트가 고의 또는 과실로 인한 손해발생을 제외하고는 이에 대하여 책임을 부담하지 아니합니다.
제 19 조 (관할 법원)
서비스 이용으로 발생한 분쟁에 대해 소송이 제기되는 경우 민사 소송법상의 관할 법원에 제기합니다.
[부 칙]
1. (시행일) 이 약관은 2016년 9월 5일부터 적용되며, 종전 약관은 본 약관으로 대체되며, 개정된 약관의 적용일 이전 가입자도 개정된 약관의 적용을 받습니다.