• Title/Summary/Keyword: PHYSICAL EFFECT

Search Result 10,969, Processing Time 0.049 seconds

Studies on the Propagation of the Freshwater Prawn, Macrobrachium nipponense (De Haan) Reared in the Laboratory (담수산 징거미새우, Macrobrachium nipponense (De Haan)의 증${\cdot}$양식에 관한 생물학적 기초연구 1. 생식생태에 관한 연구)

  • Kwon Chin-Soo;Lee Bok-Kyu
    • Journal of Aquaculture
    • /
    • v.4 no.1
    • /
    • pp.31-66
    • /
    • 1991
  • This paper deals with the reproductive ecology e.g., number of the pre-spawning moults, morphological characteristics of the pre-spawning moult the common moult, daily ration druing a molting cycle mating behavior, structures of spermatozoa and spermatophore, structure of vas deferens, mechanisms of the oviposition and brooding into the egg-chambers, a suitable time for the artificial mating and fertilization, time sequence of the oviposition and brooding into egg-chambers from the copulation, responses to temperature and chlorinity on the egg development and hatching, effect of temperatures on duration of egg development, physical mechanism of the egg hatching, to make an attempt for the artificial spawning and brooding to establish a suitable system of the artificial seedling-production for the aquaculture. 1. Females molted commonly $8{\~}10$ times at an interval of $17{\~}18$ days at $28^{\circ}C,\;3.26\~4.35\%_{\circ}$ while the prespawning moltings were $4{\~}5$ times at an interval of $13{\~}14$ days. The suitable state for artificial copulation was within 14 hours elapsed from the prespawning moltings (most suitable state was within 8 hours). Males discharged a gelatinous spermatophore and placed it on the females sternum during copulation. Oviposition was seen $6{\~}17$ hours after copulation. External fertilization was considered to take place at oviposition. Fertilized eggs held in egg-chambers forming between pleopods were about $5000{\~}6000$ in females those sizes about 6.5 cm in body length. 2. Eggs immediately after oviposition were elliptic shape, measuring $0.58{\times}0.48$ mm up to hatching. Their sizes increased with egg development and finally reached $0.85{\times}0.54$ mm up to hatching. The relationship between the long axis of the egg(Y in U) and days elapsed(X) was expressed as Y= 5.60194 + 0.007358X. The eggs performed superficial cleavage and their cleavage furrows became visible at the 4-daughter-nucleus stage. The eggs showed normal development up to hatching at water temperature range of $22{\~}30^{\circ}C$ (optimum temperature : $26{\~}28^{\circ}C$) and at chlorinity range of $0.00\~6.64\%_{\circ}$ (optimun chlorinity : $2.21{\%}_{\circ}$). The relationship between incubation period (Y in days) and water temperature(X in $^{\circ}C$) could be expressed as Y= 50.803-1.3555X. The eggs hatched $12{\~}13$ days after oviposition at $28.0{\~}28.6^{\circ}C$ 3. The pre-spawning moltings were appreciably different in the morphologic structure from those of common moltings. Breeding setae and dresses were formed on the thoracic regions, abdominal epimerae and the bases of the first to fourth pleopods in order to prepare and support oviposition, transfering and supporting eggs in egg-chambers up to hatching. These supplementary breeding organs were observed only at reproductive seasons.

  • PDF

Neighborhood Park Design for Railroad Station in Uijeongbu City (의정부 역전 근린공원 설계)

  • Kwon, Jin-Wook
    • Journal of the Korean Institute of Landscape Architecture
    • /
    • v.38 no.4
    • /
    • pp.64-74
    • /
    • 2010
  • The study is based on an urban park design that is designed in consideration of the characteristics of Uijeongbu City, applied with adequate functions for the environment and showcasing the unique scenery in relation to the relocation of the US Air Force Camp Falling Water. The bases of the design are: the reasonable convergence of the square and park in consideration of the site characteristics; the application of an urban context as the park is located near a station; and the realization of an eco-friendly space. This study is based on foundation research regarding a review of urban square patterns, particular items in planning in relation to modern urban parks and the adaptability of the park in the future. Regarding space usage, the design is applied with notable ideas that allow the space to make its own characteristics through voluntary user activity in conjunction with the environment that will allow the park to cope with changes in the future, as opposed to a space that users experience through pre-determined programs. Below are the focal points of the design. First, the park is designed as an empty space which may accommodate the urban structural context of and usage patterns for being a field of the city ecology that changes and develops, beyond a passively-created square pattern. Such open spaces have a continuity which allows it to adapt to the development of the city. In addition, the design facilitates spontaneous processes through changes in usage pattern and time. Second, the design includes the message that the park and the city, natural things and artificial things, must communicate and network with each other. Hence the park shall not be an isolated green island within the city, but is an open space accommodating the demands for open area from nearby commercial, public and residential facilities; the park shall include a field that can accommodate a variety of programs. Third, the park is designed to encourage the effect of direct and indirect practical education by reflecting a physical plan as well as interesting experience design methods to lower carbon emissions and to create and maintain an eco-friendly space, the basis of a zero-emissions city.

Effect of Reused Cocopeat Substrate on Growth and Yield of Summer-cultivated Paprika in EC-based Recycling Hydroponic Cultivation (EC기준 순환식 수경재배에서 코크피트배지 재사용이 여름작형 파프리카의 생육 및 수량에 미치는 영향)

  • Jang, Dong-Cheol;Choi, Ki-Young;Yeo, Kyung-Hwan;Kim, II-Seop
    • Journal of Bio-Environment Control
    • /
    • v.26 no.2
    • /
    • pp.100-107
    • /
    • 2017
  • This experiment was carried out to analyze the effects of substrate reuse on the growth and yield of summer paprika in cyclic hydroponics. The test group was divided into a new coco slab, one year reused coco slab two year reused coco slab based on 30% nutrient solution reuse, and was performed from April 18 to November 31, 2016 for 30 weeks. As a result, plant height of early growth was that the 2 year reused slab was longer than the new slab but the final growth period was 56.58 cm shorter. First group flower position was that reused slab was shorter by 2.92 cm than the new slab and the second group flower position was 0.31 cm long. The relative internode length of early growth, when the reused slab was used, the imbalance in the late growth stage was increased compared with the use of the new slab. The number of growth nodes in the 1 and 2 year reused slab was the smallest with 27.4 nodes. However, the number of harvested nodes did not show the difference in the test group, and the ratio of harvested that the 2 year reused slab was the highest at 26.8%. The ratio of unmarketable fruit tended to increase as the growth progressed. Fresh weight was 227.7g for new slab, 219.2g for 2 year reused slab and 21.2g for 1 year reused slab. The dry weight of the new slab increased with the reuse of the slab. It was 17.13g for new slab, 18.26g for 1 year reused, and 19.28g for 2 year reused. The average water content of the entire growth period was smaller as the slab was reused, and the 1 year reused slab was about 20g less than the 2 year reused slab. This trend was steadily occurring throughout the entire growing season. Especially, the reused slab for 1 year was less than 60g after 3 groups compared to other test groups. In conclusion, If will control seriously occurrence of unmarketable fruits by weakening after medium growth in summer-cultivated paprika in EC-based recycling hydroponic cultivation with reused cocopeat substrate, It is not what I have to worry that decrease of the yield and deterioration of the quality due to the change of physical and chemical properties of the slab and the pathogenic bacteria infection.

A Study on the Effects of Store Choice Criteria of Mass Merchandisers on Store Loyalty with Customer Emotions as Moderating Variables (대형마트 점포선택기준이 점포애호도에 미치는 영향)

  • Oh, Young-Ho;Jung, Yong-Tae
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
    • /
    • v.6 no.3
    • /
    • pp.147-175
    • /
    • 2011
  • The purpose of this study is to examine the effects of store choice criteria on customer satisfaction and store loyalty, and the moderating effects of customer emotions on the causal relationship between store choice criteria and customer satisfaction. In this regard, this study tries to identify the effects of store choice criteria on customer satisfaction and store loyalty in case of mass merchandisers, and to analyze the moderating effects of customer emotions on the causal relationship between store choice criteria and customer satisfaction. For this purpose, 300 customers, who have ever shopped at mass merchandisers, were surveyed and 246 valid responses were finally used for the data analysis. The results of this study are as follows. First, out of six store choice criteria, product factors, store reputation and physical environment turn out to have statistically significant effects on customer satisfaction. This result confirms those of the previous studies. On the other hand, store accessibility, subsidiary facilities and store atmosphere are not found to have statistically significant effects on customer satisfaction. This result is somewhat different from those of previous studies, and so further research on the subject needs to be carried out. Secondly, it turns out that customer satisfaction has a statistically significant effect on store loyalty, which is in line with the results of previous studies that perceived emotions affect customers' store attitudes which in turn influence their revisit intentions. Thirdly, as for the moderating effects of customer emotions on the relationship between store choice criteria and customer satisfaction, pleasure moderates the effects of store accessibility, subsidiary facilities and store atmosphere on customer satisfaction, arousal moderates the effects of product factors, subsidiary facilities and store reputation on customer satisfaction, and finally dominance moderates the effects of product factors and subsidiary facilities on customer satisfaction. These findings partially support the results of previous studies that customers' in-store emotional experiences such as feeling good or bad enhance their store loyalty.

  • PDF

Preparation and physical properties of flame retardant high density polyethylene utilizing inorganic waste shell powder (재활용(再活用) 굴 껍질 분말(粉末)을 이용(利用)한 고밀도 폴리에틸렌계 난연 소재(素材)의 제조(製造)와 물성(物性))

  • Choi, Jae-Won;Cho, Tae-Keun;Ahn, Jun-Hyung;Lee, Sung-Ho;Chung, Yong-Chan;Jeon, Ho-Seok;Chun, Byoung-Chul
    • Resources Recycling
    • /
    • v.17 no.4
    • /
    • pp.21-29
    • /
    • 2008
  • Waste shell powder was added to the high density polyethylene(HDPE), and resultant mechanical properties and flame retardancy were analyzed in terms of shell content. Compatibilizer(PE-g-MA) was used to enhance the mechanical properties of the prepared HDPE/shell composites, and several flame retardant agents($Al_2O_3$, $Sb_2O_3$) were utilized to improve flame retardancy. Addition of the compatibilizer resulted in an improved mechanical properties due to the increased interfacial bonding between HDPE matrix and shell powder. In the case of impact strength, it even reached to the impact strength of pure HDPE. Also the addition of the flame retardant agents did not exhibit mechanical property decrease. UL-94 flammability test on the prepared HDPE/shell composites indicated that at 40wt% of shell only inclusion, time to ignite the flame and the total time of flame duration increased. When flame retardant agents mixed with shell powder were added to the HDPE matrix, improved flame retardancy was observed. Generally, flame retardancy effect of $Al_2O_3$ was better than $Sb_2O_3$. UL-94 V-0 classification was observed for the specimens with $Al_2O_3$ and compatibilizer at more than 40wt% shell, and also for specimens with $Sb_2O_3$ and compatibilizer at all shell content.

Effects of Korean Ginseng and Tocopherol on Testosterone Content, Protein Metabolism and Stamina Promotion in Rats (흰쥐의 Testosterone 함량(含量), Protein 대사(代謝) 및 스테미너 증진(增進)에 미치는 인삼(人蔘)과 Tocopherol의 영향(影響))

  • Kim, Jae-Ryeun;Kim, Kwang-Soo;Seo, Jung-Sook
    • Journal of the Korean Society of Food Science and Nutrition
    • /
    • v.13 no.4
    • /
    • pp.427-431
    • /
    • 1984
  • This experiment was conducted to study the effects of Korean ginseng and tocopherol on serum testosterone level, protein metabolism and swimming endurance in rats. Powdered ginseng (2.5 g/kg) and ${\alpha}-tocopherol$ (250 mg/kg) were added directly into the basal diet of rats feeding for 6 weeks. The serum testosterone level of ginseng-treated rats had no difference from that of control rats, but the level was slightly increased in tocopherol-treated rats. In the case of ginseng-treated rats, there were no significant difference in the contents of albumin, ${\alpha}_1-globulin$, ${\alpha}_2-globulin$, ${\gamma}-globulin$ and A/G ratio compared with those of the control rats, however, the levels of total protein and ${\beta}-globulin$ were increased significantly(p<0.005). Total protein value of tocopherol-treated rats was higher than that of the control rats(p<0.005). In contrast, albumin content was slightly decreased. The contents of ${\alpha}_1-globulin$, ${\alpha}_2-globulin$, ${\beta}-globuiln$ and ${\gamma}-globulin$ were higher in the rats fed tocopherol diet that those obtained from the control rats. Accordingly A/G value was markedly decreased (p<0.001). In swimming endurance test, both Korean ginseng and ${\alpha}-tocopherol$ did not appear to have any effect on rats' stamina.

  • PDF

Studies on the Properties of the Fiberboard - I. Hardboard (S-1-S) from Juvenile Wood of Sycamore (Platanus orientalis L.) (섬유판(纖維板)의 재질(材質)에 관한 연구(硏究) - I. 유령(幼齡)버즘나무를 원료(原料)로 한 경질섬유판(硬質纖維板))

  • Min, Du-Sik;Shin, Dong So
    • Journal of Korean Society of Forest Science
    • /
    • v.26 no.1
    • /
    • pp.57-65
    • /
    • 1975
  • This study was carried out to examine the effect of manufacturing factors on physical properties of hardboard (S.I.S) made from the juvenile wood of sycamore (Platanus orientalis L.) The results obtained may be summarized as follows: 1. The difference among the yields of pulp treated with preheat time (defibrate condition) was significant in those of treatments. There was no difference in the yield of pulp treated with defibrate time. The yields of pulp on the tree age classes were shown the difference by 2<4<6<8 years. 2. The specific gravities of hardboard that were treated with hot pressing conditions showed us significantly in those of treatments. There was no difference on the specific gravities among hardboards, treated with resin and wax contents. But in all cases of the specific gravities satisfied the standard which specified the KS F 3203 (Hardboard) 3. The moisture contents of hardboard satisfied the standard which calls for 13-percent below. There were difference in moisture contents between hardboard, treated with preheating time, resin and wax contents and hot pressing conditions. And the moisture contents of hardboard on the tree age classes showed the difference by 2<4<6<8 years. 4. The water absorption and thickness swelling of hardboard treated with defibrations, resin and wax contents, and hot pressing conditions were significant in those of treatments. And the water absorption and thickness swelling of hardboard on the tree age classes showed us the significant difference by 8<6<4<2 years. 5. The difference among the flexural strength in using tested three conditions showed us the difference by defibration$200kg/cm^2$) of hardboard, it is likely to be recommened that the juvenile wood of sycamore is valuable for the raw materials of hardboards.

  • PDF

Are Bound Residues a Solution for Soil Decontamination\ulcorner

  • Bollag, Jean-Marc
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
    • /
    • 2003.10a
    • /
    • pp.111-124
    • /
    • 2003
  • Processes that cause immobilization of contaminants in soil are of great environmental importance because they may lead to a considerable reduction in the bioavailability of contaminants and they may restrict their leaching into groundwater. Previous investigations demonstrated that pollutants can be bound to soil constituents by either chemical or physical interactions. From an environmental point of view, chemical interactions are preferred, because they frequently lead to the formation of strong covalent bonds that are difficult to disrupt by microbial activity or chemical treatments. Humic substances resulting from lignin decomposition appear to be the major binding ligands involved in the incorporation of contaminants into the soil matrix through stable chemical linkages. Chemical bonds may be formed through oxidative coupling reactions catalyzed either biologically by polyphenol oxidases and peroxidases, or abiotically by certain clays and metal oxides. These naturally occurring processes are believed to result in the detoxification of contaminants. While indigenous enzymes are usually not likely to provide satisfactory decontamination of polluted sites, amending soil with enzymes derived from specific microbial cultures or plant materials may enhance incorporation processes. The catalytic effect of enzymes was evaluated by determining the extent of contaminants binding to humic material, and - whenever possible - by structural analyses of the resulting complexes. Previous research on xenobiotic immobilization was mostly based on the application of $^{14}$ C-labeled contaminants and radiocounting. Several recent studies demonstrated, however, that the evaluation of binding can be better achieved by applying $^{13}$ C-, $^{15}$ N- or $^{19}$ F-labeled xenobiotics in combination with $^{13}$ C-, $^{15}$ N- or $^{19}$ F-NMR spectroscopy. The rationale behind the NMR approach was that any binding-related modification in the initial arrangement of the labeled atoms automatically induced changes in the position of the corresponding signals in the NMR spectra. The delocalization of the signals exhibited a high degree of specificity, indicating whether or not covalent binding had occurred and, if so, what type of covalent bond had been formed. The results obtained confirmed the view that binding of contaminants to soil organic matter has important environmental consequences. In particular, now it is more evident than ever that as a result of binding, (a) the amount of contaminants available to interact with the biota is reduced; (b) the complexed products are less toxic than their parent compounds; and (c) groundwater pollution is reduced because of restricted contaminant mobility.

  • PDF

Properties of Indigenous Korean Paper(Hanji) - Classification of Oebal(single frame)Papermaking Methods - (토착한지의 특성 - 외발 초지법 분류를 중심으로 -)

  • Cheon, Cheol;Kim, Seong-Ju;Jin, Young-Mun
    • Journal of the Korean Wood Science and Technology
    • /
    • v.27 no.1
    • /
    • pp.88-104
    • /
    • 1999
  • This study was carried out to classify the Hanjis into three groups that were indigenous Hanji, traditional Hanji, and improved Hanji handmade by paper making method according to the physical properties of each paper sheet such as tensile, bursting and tearing strength, folding endurance and fiber orientation in each layer. The results obtained were summarized as follows: 1. The multi-layered Hanjis made by "Oebal" Hanji making method in different direction of fiber orientation have good properties in tearing resistance. 2. The multi-layered Hanji in different direction of fiber orientation has good properties in the tearing resistance, but the burst index and the breaking length results were lower than the single layered Hanjis. 3. The different fiber orientation and multi-layered method didn't increase, the three indexes(burst index, tear index, breaking length). Only, the different direction of fiber orientation decreased the difference of width and length strength (tensile, tear) of the Hanji. 4. "Dochim"(Korean finishing touch process for indigenous Hanji by fulling round sticks) greatly increase folding endurance(double folds, not $log_{10}$) and good effect to tensile strength and burst strength. 5. The today's Oebal Hanji were the maximum of 2 layers and the indigenous Oebal Hanji were 16 layers the maximum. In addition, average of the indigenous Oebal Hanji was 4 layers(all 4-layer Hanji were the different fiber orientation of each layer). 6, The indigenous Hanji(multi-layered, and different fiber orientation) was good condition with "Dochim". Dochim increased tensile strength and burst strength of the indigenous Hanji. So the three-strength indexes were similar level("--"). 7. When the number of layer which were same fiber orientation increase, the increased Hanji became similar strength pattern("V", breaking length and burst index was higher than tear index) with "Ssangbal" Hanji. 8. The single layered papers that made by "Oebal" Hanji making method were similar strength pattern with Ssangbal Hanji. 9. There was no way to find the width and length direction of multi-layered Hanji by comparison between the difference of tensile strength and the difference of tearing resistance. 10. The compared pattern of tensile strength and tearing resistance of indigenous Oebal Hanji was different from today's Oebal Hanji. Especially, the tearing resistance of all indigenous Oebal Hanji(16 samples) was stronger on width of tearing resistance. And in the half of indigenous Oebal Hanji samples, the width of tensile strength and tearing resistance was stronger than length strength (Indigenous Oebal: '$\ulcorner\lrcorner$' 50%, '$\bigcup$' 50% $\leftrightarrow$ Today's Oebal: '$\ulcorner\lrcorner$' 12%, '$\bigcup$'6%, '$\llcorner\urcorner$'17%, '$\bigcap$'65%). In 65% today's Oebal, the length direction of tensile strength and tearing resistance was stronger than the width direction.

  • PDF

Patient-related Barriiers to Pain Management in General Population (일반인의 통증관리 장애정도)

  • Yoo, Yang-Sook;Choe, Sang-Ok;Cho, Young-Yi;Koh, Su-Jin;Hor, Soo-Jin;Jeon, Ji-In;Kwon, So-Hi
    • Journal of Hospice and Palliative Care
    • /
    • v.10 no.4
    • /
    • pp.184-189
    • /
    • 2007
  • Purpose: This study was to explore barriers to effective pain management in general population. Methods: Total 163 Participants completed the Barrier Questionnaire-II (BQ-II), a 27-item on a six point scale, from May to June in 2007. BQ-II consisted of four subscales which were 1) physical effects (PE) addressing beliefs that side effects of analgesics are inevitable and concerns about tolerance, fatalism (Fa) addressing fatalistic beliefs about cancer pain and its management, Communication (Co) addressing the beliefs of 'good patient' and concerns of distracting physician from underlying disease, and harmful effects (HE) addressing fear of addiction and harmful effect to immune system of pain medicine. Results: The BQ-II total had an internal consistency of 0.877 in this study. HE was the biggest barrier (3.03) followed by PE (2.73), Fa (2.15), and Co (1.71). Items appeared as great concerns were 'there is a danger of becoming addicted to pain medication'(3.58), 'using pain medicine blocks your ability to know if you have any new pain' (3.18), 'pain medicine is very addictive' (3.09), 'when you use pain medicine your body becomes used to its effects and pretty soon it won't work any more' (3.09), and 'drowsiness from pain medicine is difficult to control' (3.09). Only 12 respondents (7.4%) reported that they took any type of pain education, however, those who took pain education represented significantly lower barriers to pain management than who did not (P=.029). Conclusion: This result suggests the strategies for public education to surmount cancer pain.

  • PDF