Formation of unit loads and determination conditions of separate types of goods transportation by air

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NATIONAL AVIAION UNIVERSITY

Department of Air Transportation Management

COMPUTING AND SCHEMATIC PAPER

on the academic subject «Cargo Science»

Theme: «FORMATION OF UNIT LOADS AND DETERMINATION CONDITIONS OF SEPARATE TYPES OF GOODS TRANSPORTATION BY AIR»

Done by: student of group FML 305a

Supervisor: Ivannikova V.Yu., Ph.D. (Engineering),

Associate Professor

Kyiv 2013



Contents

Introduction

1. Transport characteristics of goods

1.1 Tissue Paper and its properties

1.2 Space and weight characteristics

2. Carrier and type of aircraft for transportation

2.1 Transportation route

2.2 Delivering airline

2.3 Aircraft data

3. Limitations by sizes, weight and loading on the floor

4. Tare and packaging of goods

4.1 Overview of package

4.2 Calculation of number of bags that we can put into one box

4.3 Checking the observance of limitations

5. Manipulation signs

Conclusions

References

paper carrier transportation manipulation



Introduction

The aim of this paper is mastering basic positions from formation of unit loads and determination conditions of goods transportation by air. During performing of this paper we will overview the following issues, such as describing transport characteristics of goods: name of goods, peculiarities and physical state of goods, space and weight characteristics (dimensions of separate packages, weight, density, volume weight, etc.), interaction with environment, primary packaging of the given type of goods, classify given goods as general or special one, make conclusions regarding saving by goods its properties during transportation by air; determine carrier and type of aircraft for transportation according to the given route and official schedule of passenger flights; determine limitations by sizes, weight and loading on the floor during transportation of goods by the given type of aircraft (number of cargo holds, dimensions of hold doors, volume of cargo holds, maximal weight of goods, which can be loaded in cargo holds, maximal loading on the floor); select tare and packaging of goods for its transportation taking into account parameters of aircraft, on which transportation will be carried out. State standards and manuals for packaging of goods must be used during selection of tare and packaging; check observance of limitations by created unit loads according to dimensions, weight and loading on the floor during transportation by the given type of aircraft; completing tag on goods.



1. Transport characteristics of goods

1.1 Tissue Paper and its properties

Key properties are: Absorbency, basis weight, thickness (caliper), bulk (specific volume), brightness, stretch, appearance and comfort.

Absorption is a scientific property of tissue paper that involves the paper's ability to take in and hold water and other fluids. The speed of absorption and the amount of liquid that a tissue can hold are both considered important aspects of the property of tissue paper absorption. Porosity is another scientific property of tissue paper and it is closely tied to absorption because it is the pores in tissue paper that absorb fluids.

Tensile strength is another scientific property of tissue paper. It is the measurement of a matter's capability to resist tearing or splitting under the pressure of an outside force. Tensile strength in tissue paper is important during both production and consumption. It is important during production so the paper does not rip during the manufacturing process and during consumption so it stands up to consumer usage. Tissue paper tensile strength is measured for both wet and dry tissue.

The tactility properties of tissue paper are those that relate to the feel of the paper. These scientific properties include softness, smoothness and fluffiness. Tissue paper is made from either new or recycled paper pulp. The softness, smoothness and fluffiness of tissue paper varies depending upon the quality of the paper pulp, the adhesives used to hold the paper together and the types of additives that are used in the base of the paper and in optional coatings.

One of the structural scientific properties of tissue paper as mentioned in Section 1 is porosity. Porosity is more specifically defined for tissue paper as the number, size and distribution pattern of pores in a sheet of tissue paper. Additional scientific properties of tissue paper that relate to structure include weight, thickness and density. Density is most commonly defined as the mass of a substance per unit volume.

Tissue paper is produced on a paper machine that has a single large steam heated drying cylinder (yankee dryer) fitted with a hot air hood. A Yankee dryer is a pressure vessel used in the production of tissue paper. On the Yankee dryer, the paper goes from approximately 42-45% dryness to just over 89% dryness. In industry, MG cylinders or Yankee dryers are primarily used to remove excess moisture from pulp that is about to be converted into paper. The Yankee cylinder can be equipped with a doctor blade and sprayed with adhesives to make the paper stick. Creping is done by the Yankee's doctor blade that is scraping the dry paper off the cylinder surface thereby crкping the paper. The crinkle (crкping) is controlled by the strength of the adhesive, geometry of the doctor blade, speed difference between the yankee and final section of the paper machine and paper pulp characteristics The raw material is paper pulp. The yankee cylinder is sprayed with adhesives to make the paper stick. Creping is done by the yankee's doctor blade that is scraping the dry paper off the cylinder surface. The crinkle is controlled by the strength of the adhesive, geometry of the doctor blade, speed difference between the yankee and final section of the paper machine and paper pulp characteristics.

The highest water absorbing applications are produced with a through air drying (TAD) process. These papers contain high amounts of NBSK and CTMP. This gives a bulky paper with high wet tensile strength and good water holding capacity.The TAD process uses about twice the energy compared with conventional drying of paper.

The properties are controlled by pulp quality, crкping and additives (both in base paper and as coating). The wet strength is often an important parameter for tissue paper.

Tissue is made according to the GOST 6658-75, which name is “Articles of paper and cardboard. Packing, marking, transportation and storage.” This standard applies to notebooks, albums, notebooks, and other articles of paper and paperboard and establishes requirements for packaging, labeling, transportation and storage of products.

Type of primary packaging is Plastic bag. State standard, according to which goods are packed in primary packaging GOST 10354-82. This standard applies to polyethylene film, manufactured by extrusion of high pressure polyethylene (low density) and its composites containing pigments (colorants), stabilizers, lubricants, antistatic and builders. The film is used in agriculture, land reclamation and water management construction, as packaging material in various sectors of the economy, for the manufacture of consumer goods.

This type of cargo is general. It should be transported in wooden cases. Also, it should be protected from moisture.

1.2 Space and weight characteristics

Dimensions of primary packaging (LxWxH), 180х180х86

Weight of goods in primary packaging, 0.66 kg

Number of units of goods in primary packaging 4 rolls per 1 bag

Number of primary packaging in a consignment: 1000

Calculation of Volume, Net and Gross Weight:

Net weigh is weight of the cargo excluding all packing.

Gross weight is the weight of the shipment including all packing, blocking, etc. Chargeable weight is the actual gross weight or volume weight, whichever is higher.

V.W. =1000* ( L*W*H / 6000 cu.sm/kg);

V.W.=1000*(18sm*18sm*8,6sm/6000cu.sm./kg)= 464,5(kg);

N.W. = 1000*0.66= 660(kg);

G.W.= N.W. + W.P.;

W.P.- weight of packaging.(of wooden boxes);

Weight of packaging = n* W;

n- number of boxes;

W- weight of 1 box;

W.P.= 63 * 3,4kg.= 214,5 (kg)

G.W.= 660kg. +214,5kg. = 874,5 (kg.)

G.W.> V.W, so Chargeable Weight is equal:

C.V.= 874,5 (kg.)



2. Carrier and type of aircraft for transportation

2.1 Transportation route

Transportation route “Kyiv-Tashkent” will start in Kyiv Boryspil Airport, and according to its flight board there is a direct route to Tashkent on December,26. This flight starts at 12:10, duration is 7 hours 25 minutes, so the aircraft will arrive to Tashkent at 19.25. Type of airplane- Boeing 757. And the carrier is Uzbekistan Airways.

2.2 Delivering airline

The National Air Company Uzbekistan Airways, operating as Uzbekistan Airways is the national airline of Uzbekistan, headquartered in Tashkent. From its hub in Tashkent Airport, the airline serves a number of domestic destinations; the company also flies international services to Asia, Europe and North America.

Following the dissolution of the Soviet Union, Uzbek President Islam Karimov in 1992 authorised the creation of Uzbekistan Airways. The carrier was established on 28 January 1992, and took over the operations of the Uzbekistan division of Aeroflot on 31 May 1992. The airline's maiden flight was from Tashkent to London.

Domestic flights used Russian-built aircraft that formerly belonged to Aeroflot. When international routes became top priority, Airbus planes were leased, starting in 1993.

Uzbekistan Airways serves almost 50 domestic and international destinations, from Tashkent International Airport. The airline owns 11 airports, five of which have international status.

Uzbekistan Airways Technics provides technical services for Il-76, Il-62, An-2 and Yak-42 aircraft, and aircraft engines Аn-25, Тa-6А and Тa-8, also A, B, C, D and IL checks on the Boeing 767, Boeing 757, Airbus 310, Airbus 320 and RJ-85.

Since its formation, Uzbekistan Airways has mainly aimed its passenger service at Western Europe and other international locations. Most flights to international locations operate from Tashkent, although regional international services do exist.

The carrier is not part of any partnerships or alliances, but negotiations are under way to join SkyTeam, according to reports from the Uzbek government; however, no official announcement has been made so far either by the airline or the alliance.

Uzbekistan Airways serves almost 50 destinations worldwide and at home, from Tashkent International Airport. The airline owns 11 airports, five of which have international status.[citation needed] Uzbekistan Airways is not part of any partnerships or alliances, but is in talks to join the SkyTeam Alliance.

Uzbekistan Airways Technics provides technical services for Il-76, Il-62, An-2 and Yak-42 aircraft, and aircraft engines Аn-25, Тa-6А and Тa-8, also A, B, C, D and IL checks on the Boeing 767, Boeing 757, Airbus 310 and RJ-85.

According to reports from boarding.no and the Uzbek government, Uzbekistan Airways is in negotiations with SkyTeam to join the alliance; however, as of yet, no official announcement has been made by either the airline or by SkyTeam. If accepted, the membership will enable Uzbekistan Airways customers to fly to over 900 destinations worldwide on partner airlines. Uzbekistan Airways' candidacy is being sponsored by Korean Air.

Destinations

Since its formation, Uzbekistan Airways has mainly aimed its passenger service at Western Europe and other international locations. Most flights to international locations operate from Tashkent, although regional international services do exist.

Uzbekistan Airways has code share agreements with the following airlines:

Air Baltic

Air India

Czech Airlines (SkyTeam)

Korean Air (SkyTeam)

Malaysia Airlines (One World)

Fleet

Both the Boeing 757-200 and the Boeing 767-300ER entered the fleet in late 1996; the airline took delivery of these aircraft as part of an order placed in October 1995. Still in operation, both types are powered with Pratt & Whitney engines.

Uzbekistan Airways was the launch customer for the Ilyushin Il-114; it took delivery of the first, locally-assembled aircraft, in July 1998.

In mid-2007, the carrier ordered six Airbus A320s; by that time the fleet was 55 strong, comprising 10 different aircraft models; the Russian-built Yak-40 was among them. Also in mid-2007, the airline ordered two Boeing 787-8s, with a contract for the engines with General Electric worth US$70 million.[10] In late 2008, the company ordered four Boeing 767-300ERs in a US$597 million deal, and the A320 order was boosted to ten aircraft. The airline took delivery of its first A320 in July 2010; the type started operations servicing the Tashkent-Baku route. The first of four Boeing 767-300ERs ordered in 2008 was delivered in February 2012, in coincidence with the carrier's 20th anniversary. Also in 2012, the airline retired the An-24 from active service. It was informed in May 2013 that the Islamic Development Bank signed a deal for US$270 million with the Government of Uzbekistan that will be partly (US$170 million) used to finance the acquisition of two Boeing aircraft, yet the type involved was not disclosed.

Since its formation, Uzbekistan Airways has mainly aimed its passenger service at Western Europe and other international locations. Most flights to international locations operate from Tashkent, although regional international services do exist.

Table1. Uzbekistan Airways technical information

IATA code	HY
ICAO code	UZB
Call sign	UZBEKISTAN
Country	Uzbekistan
Airline type	regular
Fleet size	37
Airline destinations	58
Airline routes	79

Uzbekistan Airways flight statistics:

The average ticket fare for Uzbekistan Airways is 643 Euro; The most used airport by Uzbekistan Airways is Sri Guru Ram Dass Jee (Amritsar);

The most popular route for Uzbekistan Airways is Barajas (Madrid) - Sri Guru Ram Dass Jee (Amritsar);

The most common depart time for Uzbekistan Airways is 22:05.

List of cities served by Uzbekistan Airways in alphabetical order:

A: Abu Dhabi, Amritsar, Almaty, Astana, Andizhan;

B: Baku, Beijing, Bishkek, Bangkok, Bukhara;

C: Christchurch; D: Dubai; F: Frankfurt, Fergana; G: Geneva;

I: Islamabad, Istanbul;

K: Kuala Lumpur, Kaliningrad, Kazan, Krasnodar, Kiev, Krasnojarsk, Karshi; L: Lahore, London ;

M: Madrid, Mumbai, Milan, Mineralnye Vody, Moscow;

N: New Delhi, Novosibirsk, New York, Namangan , Navoi, Nukus;

O: Osaka ; P: Paris; R: Rome, Riga, Rostov on Don;

S: Sharjah, Seoul, Sochi, Samara, Saint Petersburg, Samarkand, Simferopol;

T: Tel Aviv, Tokyo, Tashkent, Tyumen, Termez;

U: Ufa, Urgench; V: Vladivostok, Volgograd; Y: Yekaterinburg; Z: Zarafshan.

2.3 Aircraft data

The Boeing 757 is a mid-size, narrow-body twin-engine jet airliner that was designed and built by Boeing Commercial Airplanes. It can carry approximately 5 tones of cargo together with the full passenger load. The aircraft has two underfloor holds consisting of five compartments. The forward hold (1 and 2 compartment) is fitted with a three-bin sled installation which is extendable from about 20” behind the forward hold door to the rear of the hold. The rear hold is divided into two sections. The forward section (compartment 3 & 4) is fitted with a two sled installation and the rear section (compartment 5) is a bulk compartment. Cargo and mail are loose loaded on this aircraft, which does not carry Unit Load Devices.

It is the manufacturer's largest single-aisle passenger aircraft and was produced from 1981 to 2004. The twinjet has a two-crew member glass cockpit, turbofan engines, a conventional tail and, for reduced aerodynamic drag, a supercritical wing design. Intended to replace the smaller three-engine 727 on short and medium routes, the 757 can carry 200 to 289 passengers for a maximum of 3,150 to 4,100 nautical miles (5,830 to 7,600 km), depending on variant. The 757 was designed concurrently with a wide-body twinjet, the 767, and owing to shared features pilots can obtain a common type rating that allows them to operate both aircraft.

The 757 is a low-wing cantilever monoplane with a conventional tail unit featuring a single fin and rudder. Each wing features a supercritical cross-section and is equipped with five-panel leading edge slats, single- and double-slotted flaps, an outboard aileron, and six spoilers. The wings are largely identical across all 757 variants, swept at 25 degrees, and optimized for a cruising speed of Mach 0.8 (533 mph or 858 km/h). The reduced wing sweep eliminates the need for inboard ailerons, yet incurs little drag penalty on short and medium length routes, during which most of the flight is spent climbing or descending. The airframe further incorporates carbon-fiber reinforced plastic wing surfaces, Kevlar fairings and access panels, plus improved aluminum alloys, which together reduce overall weight by 2,100 pounds (950 kg).

To distribute the aircraft's weight on the ground, the 757 has a retractable tricycle landing gear with four wheels on each main gear and two for the nose gear. The landing gear was purposely designed to be taller than the company's previous narrow-body aircraft in order to provide ground clearance for stretched models. In 1982, the 757-200 became the first subsonic jetliner to offer carbon brakes as a factory option, supplied by Dunlop. The stretched 757-300 features a retractable tailskid on its aft fuselage to prevent damage if the tail section contacts the runway surface during takeoff.

Besides common avionics and computer systems, the 757 shares its auxiliary power unit, electric power systems, flight deck, and hydraulic parts with the 767.Through operational commonality, 757 pilots can obtain a common type rating to fly the 767 and share the same seniority roster with pilots of either aircraft. This reduces costs for airlines that operate both twinjets

Fig. 1 Scheme of aircraft

Table 2 Specifications of aircraft

	757-200	757-200PF	757-300
Flight deck crew	Two
Seating, typical	200 (two-class) 239 (one-class)	N/A	243 (two-class) 289 (one-class)
Cargo capacity	1,670 ftі (43.3 mі)
Length	155 ft 3 in (47.32 m)	178 ft 8 in (54.47 m)
Wingspan	124 ft 10 in (38.05 m)
Tail height	44 ft 6 in (13.56 m)
Wing area	1,951.0 sq ft (181.25 m2)
Wing sweepback	25°
Wing aspect ratio	7.988
Wheelbase	60.0 ft (18.29 m)	73.3 ft (22.35 m)
Empty weight	127,520 lb (57,840 kg)	142,400 lb (64,590 kg)
Maximum takeoff weight (MTOW)	255,000 lb (115,680 kg)	272,500 lb (123,600 kg)
Takeoff distance at MTOW (sea level, ISA, RB211-535E4B engines)	6,500 ft (1,981 m)	7,800 ft (2,377 m)
Cruise speed	Mach 0.80 (530 mph, 458 knots, 850 km/h at cruise altitude of 35,000 ft or 10.66 km)1
Range, loaded	3,900 nmi (7,222 km) 4,100 nmi (7,600 km) with winglets	3,150 nmi (5,834 km)	3,395 nmi (6,287 km) 3,595 nmi (6,658 km) with winglets
Maximum fuel	11,489 US gal (43,490 L)	11,276 US gal (42,680 L)	11,466 US gal (43,400 L)
Service ceiling	42,000 ft (12,800 m)
Engines (Ч2)	Rolls-Royce RB211 Pratt & Whitney PW2037 PW2040	Rolls-Royce RB211 Pratt & Whitney PW2037 PW2040 PW2043
Thrust (Ч2)	PW: 36,600-42,600 lbf (162.8-189.4 kN) RR: 37,400-43,500 lbf (166-193.5 kN)



3. Limitations by sizes, weight and loading on the floor

Limitations by sizes, weight and loading on the floor during transportation of goods by the given type of aircraft. (table 3)

Table 3. Limitations

Compartment	1	2		3	4	5
Hold	Forward		Centre	Rear
Max. Comp. load	800	3464	(Kg)	2810	1699	2476
Max. Floor loading	732	732	(Kg/sq. m)	732	732	732
Usable Volume	4.64	13.05	(Cu. m.)	13.56	6.85	6.62



4. Tare and packaging of goods

Rolls of tissue are packed in plastic bags, 4 rolls in each bag. Dimensions of one bag is 180/180/86. Plastic bags are packed into wooden boxes . Wooden crates are approved for transport and storage even of dangerous products in the packaging groups X, Y and Z for all classes (except classes 1 and 7). Wooden boxes are suitable for all types of internal packaging such as glass and plastic bottles, metal boxes).

4.1 Overview of package

Fig. 2 Wooden box

External dimensions of box (mm): 400/400/400;

Internal dimensions of box(mm): 380/388/388;

Type of the box: UN 4DV444;

Weight: 3,4 kg

Capacity: 37 kg

The standard of this type of box is GOST 2991-85 “Planked disposable boxes for loads up to 500 kg. General specifications” This standard applies to planked disposable dense and trellised boxes with the sum of gaps in each of the walls up to 50%, inclusive, for loads up to 500 kg, designed for packaging, storage and transportation of specific types of products.

Does not apply to multi-boxes, boxes of goods for special purposes, as well as wooden housings

4.2 Calculation of number of bags that we can put into one box

380/180= 2,1..- we can put two bags from one side;

388/180=2,02..-we can put two bags from the other side;

388/86=4,51..-we can make 4 layers of bags.

Total amount of bag in one box:

T.A.=2*2*4=16 (bags)

In general, we need to transport 1000 bags of tissue, so total amount of boxes, required for transportation is equal to:

1000/16=63 (boxes).

4.3 Checking the observance of limitations

Checking the observance of limitations by created packaging to dimensions, weight and loading on the floor during transportation by the given type of aircraft.

As it was mentioned above Boeing-757 does not carry Unit Load Devices, so we need to place wooden boxes into aircraft compartment.

Dimensions of wooden box in meters: 0,4 / 0,4 / 0,4;

Volume of the box:

V1=H*W*L= 0,4*0,4*0,4= 0,064 cu. meters;

Volume of 63 wooden boxes:

V= 63 * V1= 63* 0,064= 4,5 cu. meters;

Gross weight of all cargo = 874,5 (kg.)

Area which the cargo occupies:

S= n* W*L;

S= 63* 0,4*0,4=10,08 sq. m.

Floor loading by the cargo:

F.L. =G.W./ S;

F.L. = 874,5/ 10,08= 86,8 (kg/sq. m.)

Following all limitations by created packaging to dimensions, weight and loading on the floor during transportation by the given type of aircraft and analyzing all our calculations we can see that it is possible to put all the boxes into one compartment (compartment #4).



5. Manipulation Signs

Manipulation signs are symbols specifying a type of cargo handling. Symbols, names and purpose of manipulation signs correspond to the state standards. It is allowed to apply the placards if the sign cannot express the type of cargo handling

Table 4 Manipulation signs

	”Keep dry''- Goods bearing this symbol must be protected from excessive humidity and must accordingly be stored under cover. If particularly large or bulky packages cannot be stored in warehouses or sheds, must be carefully covered with tarpaulins. This sign should be attached to the wooden boxes.
	“Don't use hooks” - Any other kind of point load should be also avoided with goods market with this symbol. The symbol does not automatically prohibit the use of the plate hooks used for handling bagged cargo. Sign is applied to the packaging when in loading and unloading operations is unacceptable to use hooks. This sign also should be attached to the boxes.

Completing of bar coded package label.

A barcode is an optical machine-readable representation of data relating to the object to which it is attached. Originally barcodes systematically represented data by varying the widths and spacings of parallel lines, and may be referred to as linear or one-dimensional (1D). Later they evolved into rectangles, dots, hexagons and other geometric patterns in two dimensions (2D). Although 2D systems use a variety of symbols, they are generally referred to as barcodes as well. Barcodes originally were scanned by special optical scanners called barcode readers. Later, scanners and interpretive software became available on devices including desktop printers and smartphones. The earliest, and still the cheapest, barcode scanners are built from a fixed light and a single photosensor that is manually "scrubbed" across the barcode.

Barcode scanners can be classified into three categories based on their connection to the computer. The older type is the RS-232 barcode scanner. This type requires special programming for transferring the input data to the application program.

"Keyboard interface scanners" connect to a computer using a PS/2 or AT keyboard-compatible adaptor cable (a "keyboard wedge"). The barcode's data is sent to the computer as if it had been typed on the keyboard.

Like the keyboard interface scanner, USB scanners are easy to install and do not need custom code for transferring input data to the application program. On PCs running windows the HID interface emulates the data merging action of a hardware "keyboard wedge", and the scanner automatically behaves like an additional keyboard. Barcode verification examines scanability and the quality of the barcode in comparison to industry standards and specifications. Barcode verifiers are primarily used by businesses that print and use barcodes. Any trading partner in the supply chain can test barcode quality. It is important to verify a barcode to ensure that any reader in the supply chain can successfully interpret a barcode with a low error rate. Retailers levy large penalties for non-compliant barcodes.

Airline name UZBEKISTAN AIRWAYS
Air Waybill NO. 307-12456712
DEATINATION TAS	TOTAL OF NO OF PIECE 63
TRANSFER POINTS	WEIGHT OF THIS PIECE 14 KG
TOTAL WEIGHT OF THIS SPIPPMENT 874,5 KG	HWB NO
BAR CODED INFORMATION

Fig. 3 Bar coded package label



Conclusions

In this computing and schematic paper we have done all the tasks, such as determining key properties of the transported cargo, its space and weight characteristics. We mentioned the information about GOSTs of transported goods, its primary package and transport package. After this we planned the transportation route Kyiv-Tashkent according to its flight board of Kyiv Borispol Airport there is a direct route to Tashkent on December,26. Then we overview the data about the carrier and type of aircraft for transportation.

Carrier is The National Air Company Uzbekistan Airways, and the type aircraft is Boeing-575.

According to the limitations by sizes, weight and loading on the floor during transportation of goods by the given type of aircraft we find the suitable kind of box for transportation. Also, we find out that this type of aircraft do not use Unit Loading Devices for transportation of cargo.

After performing space and weight calculations we checked the observance of limitations by created packaging to dimensions, weight and loading on the floor during transportation by the given type of aircraft. Having analyzed all our calculations we made a conclusion that it is possible to put all the boxes into one compartment (compartment #4).

On the final stage of our paper we mentioned manipulation signs which should be attached to each box and also completed bar coded package label.



References

1. http://www.airlines-inform.ru/commercial-aircraft/Boeing-757-200.html

2. http://www.uzairways.com/

3. http://standartgost.ru/%D0%93%D0%9E%D0%A1%D0%A2%206658-75

4. http://base1.gostedu.ru/7/7262/

5. http://standartgost.ru/%D0%93%D0%9E%D0%A1%D0%A2%202991-85

6. Book “ Cargo Science” T.Yu. Gabrielova, V. Uu Ivannikova

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