• Korean Journal of Soil Science and Fertilizer
• /
• v.33 no.4
• /
• pp.292-301
• /
• 2000

To make a better use of the beneficial bacterial inoculants in the agricultural practice, dry forms of bacterial fertilizer or pesticides are prepared with carrier materials. During the drying process of bacterial inoculant, most of the cells face a severe osmotic pressure and dehydration, and die off. Our study describes the effect of osmoprotectants such as trigonelline and trehalose on the survival of bacterial cells in high salt concentration and drying conditions. A fluorescent Pseudomonas, strain SSL3, used in this study, could grow in high salt concentration of upto 5% but the cells could not overcome the growth retardation at over 7% of salt concentration. The addition of trigonelline, even on small amount, in liquid medium containing 4% NaCl was detrimental to the cell. However, the addition of trehalose of upto 10 mM to the liquid medium containing 4% NaCl, enhanced cell growth. The cell growth was retarded when 150mM trehalose was added to the medium. Upon dry formulation of cells, trehalose was added. And the dry cells were inoculated into the soil to determine the effect of osmoprotectants on the survival of the cells. The survival of the cells, both in wet or dry soil, was improved by the addition of trehalose during the dry cell formulation. The positive effect of trehalose on the cell survival at $-20^{\circ}C$ and $-70^{\circ}C$ was oven more pronounced. The FTIR (Fourier transformation infra-red) spectroscopic analysis showed that the change of the 2nd amide group was reduced by adding trehalose to the medium containing 4% NaCl. These results suggest that trehalose can protect the cell membrane from dryness or high concentration of salt, thereby diminishing the sudden change of the protein structure of the cell membrane and, as a consequence, improving the cell survival.

• Korean Journal of Soil Science and Fertilizer
• /
• v.25 no.1
• /
• pp.1-7
• /
• 1992

Sand and silt size fractions of soils which were derived from five major rocks of granite, granite-geniss, limestone, shale, and basalt in Korea were studied. Determination of the mineralogical and chemical composition of rock-forming mineral breakdown which is accompanied by the formation of secondary minerals. The chemical composition of the fraction was largely changed with the content of weatherable and resistant soil minerals such as ferromagenesian minerals, carbonates, and guartz. In the sand fractions of the soils from the granite and granite-gneiss, chlorite-vermiculite mixed layers seem to be an intermediate weathering product prior to the weathering state of the formation of vermiculite from chlorite. Kaolin minerals in the silt fractions of the soils from the granite-gneiss are considered to be formed by the pseudomorphic transformation of plagioclase. In the sand and silt fractions of the soils derived from the limestone, large amount of calcite and dolomite seems to have been inherited from the parent rocks. The primary chloritc, micas, and feldspars are considered to be formed from the weathering remains after leaching of carbonate minerals during the soil formation. In the residual soils(Gueom series) developed from the basalt, quartz and micas were coexisted with plagioclase and augite inherited from the parent rock.

• Korean Journal of Ichthyology
• /
• v.19 no.2
• /
• pp.107-111
• /
• 2007

Sex differentiation of the brown croaker Miichthys miiuy (Basilewsky) is described from hatching to the 120th day post-hatching (dph) (water temperature $24^{\circ}C$). Primordial germ cells (PGCs) were observed on the 20th dph (10.4 mm total length (TL), 0.14 g body weight (BW), and began to protrude into the peritoneal cavity from the 40th dph (19.4 mm TL, 0.39 g BW). On the 65th dph (31.3 mm TL, 0.93 g BW, $1,560D^{\circ}$ (degree-days)), initial ovarian differentiation was identified by the PGCs with condensed chromatin, and their transformation into meiotic oocytes. By the 120th dph (4.60 mm TL, 1.38 g BW, $2,880D^{\circ}$), the oocytes were in the perinucleolus stage and had increased from 20 to $40{\mu}m$ in diameter. While ovaries gradually grew after sex was differentiated, testes continued to multiply from the 65th dph. On the 80th dph (37.9 mm TL, 1.39 g BW, $1,920D^{\circ}$), the beginning of testis lobule formation was indicated by the occurrence of spermatogonial cysts enveloped by somatic cells in some of the testes. On the 120th dph, the testis lobules of some of the fish contained all germ cell stages through to the spermatocytes. Therefore, the sex differentiation type of the brown croaker is identified as gonochoristic.

• Journal of the Economic Geographical Society of Korea
• /
• v.22 no.4
• /
• pp.438-457
• /
• 2019

The main purpose of this paper is to identify the entry types and locational determinants of North Korean workers in cross-border regions between North Korea and China. More specifically, the paper has attempted to divide the entry type of them in the regions into two; 1) entry via transactions between Chinese traders with North Korea and North Korea trade companies, and 2) entry via transactions between Korean-Chinese middlemen and North Korean trade companies. Also, it has analyzed main factors of their locational determinants in the spatial contexts of the regions. There have been changes in two perspectives in terms of the entry paths and types of them in accordance with the transformation of characteristics of United Nations sanction against North Korea from 'call-upon' to 'decide' after UN Security Council Resolution 2094 in 2013. Firstly, main agents who have dealing with North Korean trade companies which have right to dispatch North Korean workers have been changed from Chinese traders into Korean-Chinese brokers who are specialized in the introduction of North Korean workers with one-stop service from visa administrative to labor managements. Secondly, there has been a transfer of North Korean workers in the regions from formal to informal workers who has been admitted into China with a short stay or a tourist visa, and then remained illegally to be employed in China. Therefore, as demands on service which is able to guarantee the security of North Korean informal workers and their managements have increased, Korean-Chinese brokers have been stimulated in the regions after the operation of real international sanctions against overseas North Korean workers. In addition, the main factors of their locational determinants in cross-border regions between North Korea and China are could be analyzed in three perspectives; 1) an increase in real wages in accordance with the reform of the Chinese social insurance system after 2011, 2) the structural vulnerability of labor markets in the regions, 3) the utilization of stable and manageable workers.

• Journal of the Korean Geotechnical Society
• /
• v.21 no.2
• /
• pp.113-120
• /
• 2005

An understanding of soil-structure interaction is the key to rational and economical design for laterally loaded drilled shafts. It is very difficult to formulate the ultimate lateral capacity into a general equation because of the inherent soil nonlincarity, nonhomogeneity, and complexity enhanced by the three dimensional and asymmetric nature of the problem though extensive research works on the behavior of deep foundations subjected to lateral loads have been conducted for several decades. This study reviews the four most well known methods (i.e., Reese, Broms, Hansen, and Davidson) among many design methods according to the specific site conditions, the drilled shaft geometric characteristics (D/B ratios), and the loading conditions. And the hyperbolic lateral capacities (H$_h$) interpreted by the hyperbolic transformation of the load-displacement curves obtained from model tests carried out as a part of this research have been compared with the ultimate lateral capacities (Hu) predicted by the four methods. The H$_u$ / H$_h$ ratios from Reese's and Hansen's methods are 0.966 and 1.015, respectively, which shows both the two methods yield results very close to the test results. Whereas the H$_u$ predicted by Davidson's method is larger than H$_h$ by about $30\%$, the C.0.V. of the predicted lateral capacities by Davidson is the smallest among the four. Broms' method, the simplest among the few methods, gives H$_u$ / H$_h$ : 0.896, which estimates the ultimate lateral capacity smaller than the others because some other resisting sources against lateral loading are neglected in this method. But it results in one of the most reliable methods with the smallest S.D. in predicting the ultimate lateral capacity. Conclusively, none of the four can be superior to the others in a sense of the accuracy of predicting the ultimate lateral capacity. Also, regardless of how sophisticated or complicated the calculating procedures are, the reliability in the lateral capacity predictions seems to be a different issue.

• The Korean Journal of Air & Space Law and Policy
• /
• v.4
• /
• pp.7-35
• /
• 1992

The expansion of air transport on a global scale with ever increasing traffic densities has brought about problems that must be solved through new multilateral mechanisms. Looking to the immediate future, air transport will require new forms of international cooperation in technical and economic areas. Air transport by its very nature should have been a counterforce to nationalism. Yet, the regulatory system in civil aviation is still as firmly rooted in the principle of national sovereignty as when it was first proclaimed at t-11e Paris Convention of 1919 and reaffirmed in the Chicago Convention. Sovereignty over the airspace has remained the cornerstone of relations between states in all respects of air transport. The importance of sovereignty over air space embodied in article 1 of the Chicago Conrenton also is responsible for restricting the authority of ICAO as an intergovernmental regulatory agency. The Orgenization, for all its extensive efforts, has only limited authority. ICAO sets standards but cannot enforce them; it devises solutions but cannot impose them. To implement its rules ICAO most rely not so much on legal requirements as on the goodwill of states. It has been forty-eight years since international community set the foundations of the international system in civil aviation action. Profound political, economic and technological changes have taken place in air transport. The Chicago Convention is living proof that staes can work together to make air transport a safe mode of travel. The law governing international civil auiation is principally based on international treaties and on other regulation agreed to by governments, for the most part through the mechanism of ICAO. The role of ICAO international standards and recommended practices and procedures dealing with a broad range of technical matters could hardly be overestimated. The organization's ability to develop these standards and procedures, to adapt them continuously to the rapid sate of change and development of air transport, should be particularly stressed. The role of ICAO in the area of the development of multilateral conventions on international air law has been successful but to a certain degree. From the modest starting-point of the Tokyo Convention, we have seen more adequate international instruments prepared within the scope of ICAO activities, adopted: the Hague Convention of 1970 for the suppression of Unlawful Seizure of Aircraft and the Montreal Convention of 1971 for the Suppression of Unlawful Acts against the Safety of Civil Aviation. The work of ICAO in the new domain of international law conventions concerning what has been loosely termed above as the criminal problems connected with international air transport, in particular the problem of armed aggression against aircraft, should be positively appreciated. But ICAO records in the domain of developing a uniform legal system of international carriage by air are rather disappointing. The problem of maintaining and developing the uniformity of this regulation exceeds the scope of interest and competence of governmental transport agencies. The expectations of mankind linked to it are too great to give up trying to restore the uniform legal system of international air carriage that would create proper conditions for its further growth. It appears that ICAO has, at present, a good opportunity for doing this. The hasty preparation of ICAO draft conventions should be definitely excluded. Every Preliminary draft convention ought to be sent to Governments of all member-States for consideration, So that they could in form ICAO in due time of their observation. The problom of harmonizing a uniform law of international air carriage with that of other branches of international transport should demand more and more of its attention. ICAO cooperation with other international arganization, especially these working in the field of international transport, should be strengthened. ICAO is supposed to act as a link and a mediator among, at times the conflicting interests of member States, serving the happiness and peace of all of the world. The transformation of the contemporary world of developing international relations, stimulated by steadily growing international cooperation in its various dimensions, political, economic, scientific, technological, social and cultural, continuously confronts ICAO with new task.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.1 no.1
• /
• pp.33-42
• /
• 1981

Current standard code for R.C. design consists of two conventional design parts, so called WSD and USD, which are based on ACI 318-63 and 318-71 code provisions. The safety factors of our WSD and USD design criteria which are taken primarily from ACI 318-63 code are considered to be not appropriate compared to out country's design and construction practices. Furthermore, even the ACI safety factors are not determined from probabilistic study but merely from experiences and practices. This study investigates the safety level of R.C. flexural members designed by the current WSD safety provisions based on Second Moment Reliability theory, and proposes a rational but efficient way of determining the nominal safety factors and the associated flexural allowable stresses of steel bars and concretes in order to provide a consistent level of target reliability. Cornell's Mean First-Order Second Moment Method formulae by a log normal transformation of resistance and load output variables are adopted as the reliability analysis method for this study. The compressive allowable stress formulae are derived by a unique approach in which the balanced steel ratios of the resulting design are chosen to be the corresponding under-reinforced sections designed by strength design method with an optimum reinforcing ratio. The target reliability index for the safety provisions are considered to be ${\beta}=4$ that is well suited for our level of construction and design practices. From a series of numerical applications to investigate the safety and reliability of R.C. flexural members designed by current WSD code, it has been found that the design based on WSD provision results in uneconomical design because of unusual and inconsistent reliability. A rational set of reliability based safety factors and allowable stress of steel bars and concrete for flexural members is proposed by providing the appropriate target reliability ${\beta}=4$.

• Journal of Korean Medical classics
• /
• v.24 no.4
• /
• pp.157-174
• /
• 2011

We derived following result by organizing research about processing of medicinal of before Han(漢) dynesty. The human being intake of natural substance for the purpose of treatment was what happened later than the use of natural substance as food. According to the record of by the early years of Shang(商) dynasty, we can assume that we cooked food with water and fire. The reason why there is no appearance of common production that can be included under the name of 'Tang Ye(湯液)' in the medical record discovered from Ma Wang Dui(馬王堆) is because 'Tang Ye' was yet developed. However, as the presentation of format of medicine process, there was gradual formation of medicinal fluid concept. There are quite of records on major details of cloth manufacture like washing and selection, grinding, processing of medicine from the recordings of "Wu Shi Er Bing Fang(五十二病方)", "Yang Sheng Fang(養生方)", "Za Liao Fang(雜療方)" discovered at Ma Wang Dui. It used words like 'Ze(擇)', 'Qu(去)' for the selection and 'Jiu(酒)', 'Zhuo(濯)' for the wash as a process method before cloth manufacture. When filter the processed medicine, it used words like 'Zhuo(捉)', 'Suo(索)', 'Jun(浚)' and used 'Yin Gan(陰乾)', 'Bao(暴)', 'Yang(暘)' for dry. The 'cutting(切削)' that crushes the medicine used different names based on the properties of medicines. The most frequent crush is 'Ye(冶)' and it means the powered medicine after dry. There was thermal process of mild fire(微火) and heating of 'Wen(溫)'. There are many states of medicine seen from the medical record discovered at Ma Wang Dui so they can be said as original medicine. 藥末劑 is relatively commercialized type then. Here, it includes later 湯劑 but there was no name such as 'decoction(湯)' or 'decoction of medical ingredients(湯液)'. Also, 'Fu Ju(㕮咀)' is the transformation of what was 'Fu Qie(父且)' at "Ja Liao Fang" of medical books of Ma Wang Dui with time flow. The original meaning of 'Fu Qie(父且)' is 'Fu Zu(斧俎)' and it means the crushing medicine with axe. The most important thing among the medical books of Han dynasty is "Shen Nong Ben Cao Jing(神農本草經)" and "Shang Han Za Bing Lun(傷寒雜病論)" of Zhang Zhong Jing(張仲景). "Shen Nong Ben Cao Jing" mentioned the dry method of medicine, collection and process production time, cooked and uncooked use of medicine and there are several types of medicine. Other than those, it mentioned 'Seven methods of combining herbs(七情合和)' to address cautions for combining medicines. Therefore, the 'processing of medicinal' in east Han dynasty period entered the theoretical step. However, there is only little recording on cloth manufacture of detailed medicine. From the "Shang Han Za Bing Lun" of Zhang Zhong Jing, the development in the way of 'processing of medicinal' reveled the cloth manufacture for each medicine. This tradition is continued until today and so it presents the development of purpose of 'processing of medicinal' is to greatly present the effect of medicine and to reduce the side-effect.

• Journal of the Korean Institute of Landscape Architecture
• /
• v.40 no.6
• /
• pp.112-126
• /
• 2012

The theme is to analyze the time-series changes of design elements on golf courses and golf country club and its factors influencing to the changes with regard to 81-membership country club located in the Capital Area of Seoul, created in the periods from 1964 until 2011. The research methods is to analyze the time-series changes of environmental factors influencing to the changes of the elements on the golf course by book review, and to compare and speculate the results of the analysis on the environmental factors with the time-series changes on the golf course elements of statistical analysis as like regression analysis. The research results were as follows. The first, the environmental factors influencing to the change of golf course elements were analyzed as the five elements of the golf-related policies and regulations, the economy, the numbers of golfers, PGA and KPGA golf tournaments, the golf instruments. The second, the type and scale of the location of the golf course were showing trends of transformation from flat ground to mountainous one and from small scale to large one. The third, it was analyzed that he golf course elements as like the sizes, length, numbers of golf course elements as like fairway, green, bunker, teeing ground and pond were influenced by the law and regulation, the increase of amateur golfers, the promotion of techniques of golfers, the increase of the chance of foreign course designer's involvement to domestic market through the opening of PGA and KPGA tournaments etc. The fourth, the promotion of golf instruments and the flying distance were the factors influencing to the numbers of bunker, the lengths of holes. The fifth, it was revealed that the trends of increase of sizes of ponds influenced by enacting environmenal friendly laws and regulations, considering of landscaping, reflecting of design trends followed by the opening of PGA tournaments. Finally, it was proposed that the further research would be introduced with regard to the qualitative analysis onto the changes and influential factors of golf course design.

• Journal of the Korean Institute of Navigation
• /
• v.13 no.1
• /
• pp.21-53
• /
• 1989

In the past twenty years, there has been a rapid increase in the volume of traffic in Korea due to the Korean great growth of the Korean economy. Since transformation provides an infrastructure vital to economic growth, it becomes more and more an integral part of the Korea economy. The importance of coastal shipping stands out in particular, not only because of the expansion limit on the road network, but also because of saturation in the capacity of rail transportation. In spite of this increase and its importance, coastal shipping is falling behind partly because it is givenless emphasis than ocean-going shipping and other inland transportation systems and partly because of overcompetition due to excessive ship tonnage. Therefore, estimating and planning optimum ship tonnage is the first take to develop Korean coastal shipping. This paper aims to estimate the optimum coastal ship tonnage by computer simulation and finally to draw up plans for the ship tonnage balance according to supply and demand. The estimation of the optimum ship tonnage is peformed by the method of Origin -Destimation and time series analysis. The result are as follows : (1) The optimum ship tonnage in 1987 was 358, 680 DWT, which is 54% of the current ship tonnage (481 ships, 662, 664DWT) that is equal to the optimum ship tonnage in 1998. this overcapacity result is in excessive competition and financial difficulties in Korea coastal shipping. (2) The excessive ship tonnage can be broken down into ship types as follows : oil carrier 250, 926 DWT(350%), cement carrier 9, 977 DWT(119%), iron material/machinery carrier 25, 665 DWT(117%), general cargo carrier 17, 416DWT(112%). (3) the current total ship crew of 5, 079 is more than the verified optimally efficient figure of 3, 808 by 1271. (4) From the viewpoint of management strategy, it is necessary that excessive ship tonnage be reduced and uneconomic outdated vessels be broken up. And its found that the diversion into economically efficient fleets is urgently required in order to meet increasing annual rate in the amounts of cargo(23, 877DWT). (5) The plans for the ship tonnage balance according to supply and demand are as follows 1) The establishment of a legislative system for the arrangement of ship tonnage. This would involve; (a) The announcement of an optimum tonnage which guides the licensing of cargo vessels and ship tonnage supply. (b) The establishment of an organization that substantially arrangement tonnage in Korea coastal shipping. 2) The announcement of an optimum ship tonnage both per year and short-term that guides current tonnage supply plans. 3) The settlement of elastic tariffs resulting in the protect6ion of coastal shipping's share from other tonnage supply plans. 4) The settlement of elastic tariffs resulting in the protection of coastal shipping's share from other transportation systems. 4) Restriction of ocean-going vessels from participating in coastal shipping routes. 5) Business rationalization of coastal shipping company which reduces uneconomic outdated vessels and boosts the national economy. If we are to achieve these ends, the followings are prerequisites; I) Because many non-licensed vessels are actually operating and threatening the safe voyage of the others in Korea coastal routes, it is necessary that those ind of vessels be controlled and punished by the authorities. II) The supply of ship tonnage in Korean coastal routes should be predently monitored because most of the coastal vessels are to small to be diverted into ocean-going routes in case of excessive supply. III) Every ship type which is engaged in coastal shipping should be specialized according to the characteristics of its routes as soon possible.