• Title/Summary/Keyword: 내파

Search Result 19, Processing Time 0.022 seconds

Electric Spark System as Underwater Acoustic Source - I. Pressure pulses from low electric energy - (수중음원으로써의 전기방전시스템- I. 낮은 전기에너지로부터의 음압펄스 -)

  • Kim, Sung-Boo;Kim, Sang-Han
    • The Journal of the Acoustical Society of Korea
    • /
    • v.15 no.4
    • /
    • pp.32-35
    • /
    • 1996
  • The pressure pulses generated from the underwater electric spark system ranged from 0.4 to 1.6kJ are measured with the variation of source depth and range. The characteristics of pressure pulses obtained through this experiment continue to show the same electric energy and depth dependence previously reported, but two particular phenomena are observed. First, it is observed that the peak pressure of the 1st bubble pulse induced from implosion is higher than that of the initial shock wave, which is particularily apparent to high electric energy more than 10kJ previous studies. Second, it has been reported that the energy ratio (potential energy of bubble/intrinsic energy of source) has some tendency to "droop" on the low electric energy as 0.02 for 5kJ and 0.01 for 1kJ but the results of the present experiment show that it continues to have the ratio of 0.01 near 1kJ again.

  • PDF

A Study on Culture Studies for the Circuit of Culture of Policy Discourse: Focus on Cultural Representations and Signifying Practices (정책담론의 문화흐름에 대한 문화연구: 문화적 표상과 의미의 실체를 중심으로)

  • Kim, Man-Ki
    • Journal of Digital Convergence
    • /
    • v.9 no.3
    • /
    • pp.69-79
    • /
    • 2011
  • This study is the text discourse of agenda setting through media policy on the three communities. The materials of subjects are the 71 text discourses that appeared in the columns, the special manuscripts, and the comments on the contemporary topics in 33 media. The subjects focuses on the metaphor, metonymy, and binary transposition. This kind of connotation tends to be imploded into people through media, so that it produces hyperreality. This process produces the regulation and strengthens the reality through the circuit of culture. Thus this research tries to develop the theoretical foundation for analysing the text discourse produced by the media. Also it focuses on widening the research scope to study the effects that the circuit of culture provides on the politics, society, and economics. Therefore The first, the objective meanings(denotation)which the referents of the community as T'PALACE, I'PARK, and STARCITY are 'larger scale', 'high and skyscraper', 'the rich people and the plutocrats who have very high academic career' and ' the residence place for the famous stars and successful CEOs', etc. and the subjective meanings, connotations which the referents of the community are 'The first street' transposes '1%' 'their own space' into the characteristics of the wealth of Gangnam district or Korean wealth', the additional significations which the metaphors such as 'the noble community', 'the sample for the high -level residential space', and 'the greed of 1%'. Conclusion, The significations of the symbols became imploded into the population and circulated along with the cultural streams through the media. The referents are recreated and consumed among the other communities such as the named 'PALACE', 'I'PARK', 'STARCITY' in the other areas. This kind of ideology tends to create the myths such as 'the 1% rich people of Gangnam', 'the first street of Korean wealth', and create the regulation such as 'the compound taxes for the real-estates', 'the policy of reducing the taxes for the rich', 'the policy of reducing the taxes for the 1% of the rich'. Also these regulations make the politicians operate new policies and are being utilized as 'slogan' for the politicians.

Effects of Mesh size and Material of Cages on Growth and Survival rate of the Scallop (Chlamys farreri Jones & Preston, 1904) cultured in Hanging culture in the West coast of Korea (비단가리비, Chlamys farreri 수하양식에서 채롱의 망목 및 재질에 따른 성장과 생존)

  • Park, Kwang-Jae;Song, Jae-Hee;Yoon, Sang-Pil;An, Kyoung-Ho;Park, Young-Je;Song, Hong-In
    • The Korean Journal of Malacology
    • /
    • v.28 no.2
    • /
    • pp.117-123
    • /
    • 2012
  • We studied that the effects of mesh size and material of cages on the growth of C. farreri (initial shell height 38.6 mm and shell total weight 7.2 g) held in suspension cage from September 2005 to October 2006. The experiment was performed with two mesh sizes (1 cm and 2 cm) and two materials (net and plastic) of cages in same densities. After 13 months from culture beginning, ranges of shell height and total weight were from 69.7 mm to 73.9 mm and from 36.1 g to 47.0 g, respectively. The survival rate was from 93% to 100%, respectively. The growth rates of the scallop were positively correlated with the mesh size. In the growth rate according to culture material, the growth of scallop in the plastic cage was faster than that in the net cage from September 2005 to June 2006, but the growth in the plastic was slower than that in the net cage for obstruction by attaching organisms from June to October 2006.

Effect of Stocking density on Growth and Survival rate of the Scallop, Chlamys farreri (Jones & Preston, 1904) cultured in Hanging culture in the West coast of Korea (비단가리비, Chlamys farreri 수하양식에서 수용밀도에 따른 성장과 생존)

  • Park, Kwang-Jae;Yoon, Sang-Pil;Park, Young-Je;Song, Hong-In
    • The Korean Journal of Malacology
    • /
    • v.28 no.1
    • /
    • pp.1-6
    • /
    • 2012
  • We studied that the effect of stocking density on growth and survival rate of the scallop, Chlamys farreri (initial shell height 32.97 mm and total weight 5.63 g) from June 2002 to October 2003 in the west coast of Korea. C. farreri is usually the west coast of Korea and northern China in the natural habitat of the coastal species. Range of surface water temperature in the study area was $4.3^{\circ}C$ to $25.3^{\circ}C$, salinity 29.2 psu to 32.1 psu, dissolved oxygen 5.32 mg/L to 7.51 mg/L and pH was 7.84 to 8.12, respectively. The stocking densities were 20, 30, 40 and 50 individuals per a compartment of suspension cage in culture beginning. After 16 months from initiation, ranges of shell height and mean total weight were from 64.35 mm to 76.23 mm and from 41.53 g to 64.85 g. The survival rate was from 82% to 100%. The growth rate of the scallop was negatively correlated with the stocking density. The growth of the shell height and total weight were decreased with decreasing of water temperature. Most of mortality of scallop occurred during March to April and September to October. Survival rate in the stocking density was decreased by density increase and was highest in 20 individual a compartment.

A Resource Adaptive Data Dissemination Protocol for Wireless Sensor Networks (무선 센서 네트워크를 위한 자원 적응형 데이터 확산프로토콜)

  • Kim, Hyun-Tae;Choi, Nak-Sun;Jung, Kyu-Su;Jeon, Yeong-Bae;Ra, In-Ho
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.10 no.11
    • /
    • pp.2091-2098
    • /
    • 2006
  • In this paper, it proposes a protocol of resource adaptive data dissemination for sensor nodes in a wireless sensor network. In general, each sensor node used in a wireless sensor network delivers the required information to the final destination by conducting cooperative works such as sensing, processing, and communicating each other using the battery power of a independent sensor node. So, a protocol used for transferring the acquired information to users through the wireless sensor network can minimize the power consumption of energy resource given to a sensor node. Especially, it is very important to minimize the total amount of power consumption with a method for handling the problems on implosion. data delivery overlapping, and excessive message transfer caused by message broadcasting. In this paper, for the maintaining of the shortest path between sensor nodes, maximizing of the life time of a sensor node and minimizing of communication cost, it presents a method for selecting the representative transfer node for an event arising area based on the negotiation scheme and maintaining optimal transfer path using hop and energy information. Finally, for the performance evaluation, we compare the proposed protocol to existing directed diffusion and SPIN protocol. And, with the simulation results, we show that the proposed protocol enhances the performance on the power consumption rate when the number of overall sensor nodes in a sensor network or neighbor sensor nodes in an event area are increased and on the number of messages disseminated from a sensor node.

Density Dependent Growth of Scapharca satowi in the West Coast of Korea (큰이랑피조개 Scapharca satowi의 양성 밀도별 성장)

  • 송홍인;박광재;조영록;박영제
    • Journal of Aquaculture
    • /
    • v.15 no.3
    • /
    • pp.145-155
    • /
    • 2002
  • Effect of density (30, 40, 65, 90 or 120/cage) of lantern and bottom cages on growth of the ark shell, Scapharca satowi was studied in the Korean west coast from April 2000 to October 2001, when the following range of environmental conditions prevailed : temperature : 4.2 -25.5 $^{\circ}C, salinity : 30.23-32.$15\textperthousand, dissolved oxygen : 5.12-7.16 $ml$/l, pH : 7.84-8.17, phosphate : 0.22-0.56 $\mu $M, dissolved inorganic nitrogen : 3.16-9.10 $\mu $M, suspended solid : 7.6-17.9 mg/l, chemical oxygen demand: 0.46-1.61 mg/l and chlorophyll-a : 0.92-5.93 $\mug/l. Daily growth rate of shell length ranged from 0.066 to 0.071 mm/day for the lantern net cages, and from 0.079 to 0.082 mm/day for the bottom cages. Total weight also ranged from 0.067 to 0.082 g/day in the lantern net cages, as against 0.099 to 0.114 g/day in the bottom cages. Hemoglobin content of S. satowi (55 mm shell length), which was about 3.9 g/dl during february, 2001, increased to 6.0 and 7.0 g/dl during October, 2001 in animals culture in the lantern and bottom cages, respectively. ANOVA test of the growth rate showed that the growth rate of S. satowi, was significantly dependent on rearing density and the tested culture methods (P < 0.0001). The daily growth rate of the shell length was more significantly correlated with water temperature; the growth rate of shell length and total weight showed a tendency decrease with decreasing temperature. In cages suspended at the bottom, not only the increase shell weight but also the meat obtainable from comparable sized S. satowi was greater. Survival decreased with increasing density and was optimal at the density of 30 individual/cage.

Spat Collection of the Ark shell, Scapharca in the West Coast of Korea (큰이랑피조개, Scapharca satowi의 자연채묘)

  • 송홍인;박광재;조영록;박영제
    • Journal of Aquaculture
    • /
    • v.15 no.2
    • /
    • pp.95-101
    • /
    • 2002
  • During the periods from lily to October, 2000 in Hongseong and lucy to October, 2001 in Taean in the west coast of Korea, the following environmental conditions prevailed : water temperature : 22.0~26.817, salinity 27.23 ~30.80%, dissolved oxygen 4.12 ~6.26 ml/l, pH 7.89 ~8.09, phosphate 0.39 ~0.65 $\mu m$ , inorganic nitrogen 5.05~9.26 $\mu m$, suspended solid 5.4~20.8 mg/l and chemical oxygen demand 1.12~1.87 mg/l. The B-shaped veliger larvae of the Ark shell occurred in maximum number at $25^{\circ}C$ prevailing from mid-August at Hongseong and Taean. Full grown larvae reached maximum abundance from late August. To identify the effectiveness of the substratum for spat collection, raschel net were tested to Larval settlement. The most effective depth to collect the larvae in natural environment was the collectors suspended at 7~8 m depth. At these depths, about 49 to 94 spats were found on the collector (40$\times$50 cm), The growth of shell height (Y) to shell length (X), and total weight (W) to shell length (L) could be formulated as follows respectively: Hongseong: SH = 0.7168 SL -0.6466 ( $r^2$ = 0.9839), TW = $0.0001SL^{3.1705}$ ($r^2$ = 0.9882) Taean: SH = 0.736 SL -0.8824 ($r^2$ : 0.9899), TW : 0.00005 $SL^{3.3731}$ ($r^2$ : 0.9899)

Prediction of Continuous Positive Airway Pressure Level for Treatment of Obstructive Sleep Apnea (폐쇄성 무호흡의 치료시 지속적 기도 양압치의 예측)

  • Lee, Kwan Ho;Chung, Jin Hong;Lee, Hyun Woo
    • Tuberculosis and Respiratory Diseases
    • /
    • v.43 no.5
    • /
    • pp.755-762
    • /
    • 1996
  • Background : Continuous positive airway pressure(CPAP) is doubtlessly using as a medical treatment of choice for patients with obstructive sleep apnea (OSA) syndrome. CPAP is effective in OSA patients as a physical "pneumatic pressure splint" mechanism. We have done this study for two purposes, first to seek for the factors to determine the optimal CPAP titer, second to predict the minimal CPAP titer using the determined factors. Methods: We studied a 72 OSA patients who were treated with CPAP. All of them were studied by using a two nights polysomnographic rests in hospital. We compared the patients requiring CPAP over $10cmH_2O$ with those who required CPAP under 5cm $H_2O$ to determine the factors affecting the minimal CPAP titer. Results : The high CPAP group is characterized by a significantly higher body mass index(BMI), apnea index(AI) and apnea and hyponea index(AHI) and significantly lower lowest $SaO_2$. Regression analysis using the optimal four variables resulted in the following prediction equation for CPAP titer. CPAPtiter=8.382 + 0.064 ${\times}$ BMI + 0.077 ${\times}$ AI - 0.004 ${\times}$ AHI - 0.077 ${\times}$ lowest $SaO_2$ When this regression equation was applied to the 72 patients, the mean CPAP titer as predicted by the above equation was $7.80{\pm}2.96$ mmHg. Compared this value with actually determined CPAPtiter, $7.93{\pm}4.00$mmHg, there was no significant difference between the two values. Conclusion: Obesity, apnea severity and lowest Sa02 were strongly correlated with CPAP titer. Linear regression equation for CPAP titer using these indices predicted very closely the actually measured values in the sleep laboratory.

  • PDF

A Reflection on the Consumer Culture in the Post-COVID 19 Era from the Lens of Christian Education: Learning from the Drama, Penthouse (포스트 코로나 시대의 소비문화에 대한 기독교교육의 성찰 : 드라마 「펜트하우스」를 중심으로)

  • Won, Shin-Ae
    • Journal of Christian Education in Korea
    • /
    • v.66
    • /
    • pp.113-145
    • /
    • 2021
  • As a contemporary exponent of Bauderillard's Simulation and Simulacra, this paper aims to reflect on the 'consumer culture' criticized by Baudrillard from the lens of Christian Education in reading the Drama, Penthouse related to the notions of the consumption-ideology, the desire and violence of image in the post-Covid 19 era. As Baudrillard begins to realize that the concept of simulation rooted from mass media in the modern society, he explains mass media as the emerging of Simulation or the process of Simulation will lead to the impulsion of reality, which ends up with vanishing the original reality. Baudrillard is explaining in his argument that the process of Simulation proceeds among various areas of the contemporary society being manipulated by mass media. While Simulation is the process of producing the hyperreality characterized by the excess of images that seems more real than the original reality, Simulation brought about Simulacra as excess reality or consequently exploding reality. Christian educators in the post-Covid 19 must know how to deal with critical theory by considering positive ways of avoiding questioning of how to articulate what the norm of universal consensus is in the specific situation. In other words, it should be noted that the nature of the ruling ideology and the ideology of consumption has been influenced or manipulated by mass media. Christian educators especially have to help young people in seeing the messages from the images of the screens, television, soap-opera, and commercial advertising making reality as Simulacre which is more real than the original reality. When the medium becomes the message, the power of medium makes the consumer not reach communication with it. This is the main reason in the controversy about the images on television drama, Penthouse and the impact of images on people's mind. As an exponent of McLuhan's belief that "the medium is the message", Baudrillard argues although the message and a subject of Simulacra(excessive reality) is unexpectedly disappearing, the medium itself is vanished through the silence of image. However, the task of Christian education has to fuel how we teach, learn, share and pass on the Word of God as the Message. Furthermore, it is worth noting that the Message of God cannot be vanished or burst with the impulsion of it, but exists forever. With Baudrillard's ideas of Simulation and Simulacra in mind, the work of Christian education as an observation platform can better engage the reflection on a consumer society of consumerism that makes Church community and a consumer irresistible against the Fake world.